Search results for: cell proliferation inhibition

Authors: Gloria Pinilla, Jose Manuel Baena, Patricia Gálvez-Martín, Juan Antonio Marchad

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Cartilage is a dense connective tissue with limited self-repair properties. Currently, the therapeutic use of autologous or allogenic chondrocytes makes up an alternative therapy to the pharmacological treatment. The design of a bioprinted 3D cartilage with chondrocytes and biodegradable biomaterials offers a new therapeutic alternative able of bridging the limitations of current therapies in the field. We have developed an enhanced printing processes-Injection Volume Filling (IVF) to increase the viability and survival of the cells when working with high-temperature thermoplastics without the limitation of the scaffold geometry in contact with cells. We have demonstrated the viability of the printing process using chondrocytes for cartilage regeneration. This development will accelerate the clinical uptake of the technology and overcomes the current limitation when using thermoplastics as scaffolds. An alginate-based hydrogel combined with human chondrocytes (isolated from osteoarthritis patients) was formulated as bioink-A and the polylactic acid as bioink-B. The bioprinting process was carried out with the REGEMAT V1 bioprinter (Regemat 3D, Granada-Spain) through a IVF. The printing capacity of the bioprinting plus the viability and cell proliferation of bioprinted chondrociytes was evaluated after five weeks by confocal microscopy and Alamar Blue Assay (Biorad). Results showed that the IVF process does not decrease the cell viability of the chondrocytes during the printing process as the cells do not have contact with the thermoplastic at elevated temperatures. The viability and cellular proliferation of the bioprinted artificial 3D cartilage increased after 5 weeks. In conclusion, this study demonstrates the potential use of Regemat V1 for 3D bioprinting of cartilage and the viability of bioprinted chondrocytes in the scaffolds for application in regenerative medicine.

Keywords: cartilage regeneration, bioprinting, bioink, scaffold, chondrocyte

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Authors: Shu-Jun Li, Cheng-Cao Sun, De-Jia Li

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Recently, long noncoding RNAs (lncRNAs) have been emerged as crucial regulators of human diseases and prognostic markers in numerous of cancers, including colorectal carcinoma (CRC). Here, we identified an oncogenetic lncRNA HULC, which may promote colorectal tumorigenesis. HULC has been found to be up-regulated and acts as oncogene in gastric cancer and hepatocellular carcinoma, but its expression pattern, biological function and underlying mechanism in CRC is still undetermined. Here, we reported that HULC expression is also over-expressed in CRC, and its increased level is associated with poor prognosis and shorter survival. Knockdown of HULC impaired CRC cells proliferation, migration and invasion, facilitated cell apoptosis in vitro, and inhibited tumorigenicity of CRC cells in vivo. Mechanistically, RNA immunoprecipitation (RIP) and RNA pull-down experiment demonstrated that HULC could simultaneously interact with EZH2 to repress underlying targets NKD2 transcription. In addition, rescue experiments determined that HULC oncogenic function is partly dependent on repressing NKD2. Taken together, our findings expound how HULC over-expression endows an oncogenic function in CRC.

Keywords: long noncoding RNA, HULC, NKD2, colorectal carcinoma, proliferation, apoptosis

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Authors: M. Dekmouche, M. Hadjada, Z. Rahmani, M. Saidi

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The effect of iodide ions on the corrosion inhibition of mild steel in 20% sulfuric acid in the presence of 3-méthylthio-5-p-méthoxyphényl-1,2-dithiolylium against anion (I-) A1 synthesized in our laboratory,was studied by different electrochemical techniques such as electrochemical impedance spectroscopy, potentiodynamic polarization. The obtained results showed that A1 effectively reduces the corrosion rate of steel. The adsorption of 3-méthylthio-5-p-méthoxyphényl-1,2-dithiolylium against anion (I-) followed Langmuir and temkin adsorption isotherm.

Keywords: steel XC52, corrosion, inhibition, 3-méthylthio-5-p-méthoxyphényl-1, 2-dithiolylium against anion (I-) , sulfuric acid

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Authors: Niklas Ravn-Boess, Nainita Bhowmick, Takamitsu Hattori, Shohei Koide, Christopher Park, Dimitris Placantonakis

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Background: Glioblastoma (GBM) is the most common and deadly primary brain malignancy in adults. Tumor propagation, brain invasion, and resistance to therapy critically depend on GBM stem-like cells (GSCs); however, the mechanisms that regulate GSC self-renewal are incompletely understood. Given the aggressiveness and poor prognosis of GBM, it is imperative to find biomarkers that could also translate into novel drug targets. Along these lines, we have identified a cell surface antigen, CD97 (ADGRE5), an adhesion G protein-coupled receptor (GPCR), that is expressed on GBM cells but is absent from non-neoplastic brain tissue. CD97 has been shown to promote invasiveness, angiogenesis, and migration in several human cancers, but its frequency of expression and functional role in regulating GBM growth and survival, and its potential as a therapeutic target has not been investigated. Design: We assessed CD97 mRNA and protein expression in patient derived GBM samples and cell lines using publicly available RNA-sequencing datasets and flow cytometry, respectively. To assess CD97 function, we generated shRNA lentiviral constructs that target a sequence in the CD97 extracellular domain (ECD). A scrambled shRNA (scr) with no predicted targets in the genome was used as a control. We evaluated CD97 shRNA lentivirally transduced GBM cells for Ki67, Annexin V, and DAPI. We also tested CD97 KD cells for their ability to self-renew using clonogenic tumorsphere formation assays. Further, we utilized synthetic Abs (sAbs) generated against the ECD of CD97 to test for potential antitumor effects using patient-derived GBM cell lines. Results: CD97 mRNA expression was expressed at high levels in all GBM samples available in the TCGA cohort. We found high levels of surface CD97 protein expression in 6/6 patient-derived GBM cell cultures, but not human neural stem cells. Flow cytometry confirmed downregulation of CD97 in CD97 shRNA lentivirally transduced cells. CD97 KD induced a significant reduction in cell growth in 3 independent GBM cell lines representing mesenchymal and proneural subtypes, which was accompanied by reduced (~20%) Ki67 staining and increased (~30%) apoptosis. Incubation of GBM cells with sAbs (20 ug/ ml) against the ECD of CD97 for 3 days induced GSC differentiation, as determined by the expression of GFAP and Tubulin. Using three unique GBM patient derived cultures, we found that CD97 KD attenuated the ability of GBM cells to initiate sphere formation by over 300 fold, consistent with an impairment in GSC self-renewal. Conclusion: Loss of CD97 expression in patient-derived GBM cells markedly decreases proliferation, induces cell death, and reduces tumorsphere formation. sAbs against the ECD of CD97 reduce tumorsphere formation, recapitulating the phenotype of CD97 KD, suggesting that sAbs that inhibit CD97 function exhibit anti-tumor activity. Collectively, these findings indicate that CD97 is necessary for the proliferation and survival of human GBM cells and identify CD97 as a promising therapeutically targetable vulnerability in GBM.

Keywords: adhesion GPCR, CD97, GBM stem cell, glioblastoma

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Authors: Benlaifa Meriem, Berredjem Hajira, Bouasla Radia, Berredjem Malika, Djebar Med Reda

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Toxoplasmosis is a cosmopolitan infection due to Toxoplasma gondii (T.gondii). It is a significant cause of congenital disease and an important opportunistic pathogen which has become a worldwide increasing problem due to the AIDS epidemic. Current available drugs do not give satisfactory results and often have only a static and several adverse side effects as it is the case of pyrimethamine. So, the need to develop and evaluate new drugs is critical. The purpose of this study is to investigate the in vitro and in vivo effects of the new chiral N-acylsulfonamide bis-oxazolidin-2-ones on T.gondii. In this study, anti-T.gondii RH strain activities, of two new chiral N-acylsulfonamide bis-oxazolidin-2-ones were evaluated in vitro, using a MRC-5 fibroblast tissue cultures to determine the concentration that inhibit parasite multiplication by 50% (IC50) of each drug and in vivo, by PCR detection of the tachyzoites in mice ascites after new molecules treatment, using the 35-fold repetitive B1 gene of T.gondii. The in vitro results demonstrated that the treatment with the tested molecules decreased the amount of tachyzoites in cell culture in a dose-dependent manner. The inhibition was complete for concentrations over 4 mg/ml. The IC50 of Mol 1 and Mol 2 were 1.5 and 3 mg/ml, respectively, and were quite similar to the control one (2 mg/ml). The Mol 1 was highly active against T.gondii in cell cultures than Mol 2; these results were similar to those of sulfadiazine-treated group (p < 0.05). Toxoplasma-specific DNA was demonstrated in all ascites samples from infected mice of the different tested groups. Mol 1 showed better effect than Mol 2, but it did not completely inhibit the parasite proliferation. The intensity of amplification products increased when the treatment started late after infection. These findings suggest continuous parasite replication despite the treatment. In conclusion, our results showed a promising treatment effect of the tested molecules and suggest that in vitro, the Mol 1, and Mol 2 have a dose-dependent effect and a high cytotoxicity on the studied cells. The present study revealed that concentration and duration of tested molecules treatment are major factors that influence the course of Toxoplasma infection in infected mice.

Keywords: cytotoxicity, PCR, sulfonamide, Toxoplasma gondii

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Authors: Lina Paola Orozco Marin, Yuliet Montoya Osorio, John Bustamante Osorno

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Ischemic events can culminate in acute myocardial infarction by irreversible cardiac lesions that cannot be restored due to the limited regenerative capacity of the heart. Cell therapy seeks to replace these injured or necrotic cells by transplanting healthy and functional cells. The therapeutic alternatives proposed by tissue engineering and cardiovascular regenerative medicine are the use of biomaterials to mimic the native extracellular medium, which is full of proteins, proteoglycans, and glycoproteins. The selected biomaterials must provide structural support to the encapsulated cells to avoid their migration and death in the host tissue. In this context, the present research work focused on developing a natural thermosensitive hydrogel, its physical and chemical characterization, and the determination of its biocompatibility in vitro. The hydrogel was developed by mixing hydrolyzed bovine and porcine collagen at 2% w/v, chitosan at 2.5% w/v, and beta-glycerolphosphate at 8.5% w/w and 10.5% w/w in magnetic stirring at 4°C. Once obtained, the thermosensitivity and gelation time were determined, incubating the samples at 37°C and evaluating them through the inverted tube method. The morphological characterization of the hydrogels was carried out through scanning electron microscopy. Chemical characterization was carried out employing infrared spectroscopy. The biocompatibility was determined using the MTT cytotoxicity test according to the ISO 10993-5 standard for the hydrogel’s precursors using the fetal human ventricular cardiomyocytes cell line RL-14. The RL-14 cells were also seeded on the top of the hydrogels, and the supernatants were subculture at different periods to their observation under a bright field microscope. Four types of thermosensitive hydrogels were obtained, which differ in their composition and concentration, called A1 (chitosan/bovine collagen/beta-glycerolphosphate 8.5%w/w), A2 (chitosan/porcine collagen/beta-glycerolphosphate 8.5%), B1 (chitosan/bovine collagen/beta-glycerolphosphate 10.5%) and B2 (chitosan/porcine collagen/beta-glycerolphosphate 10.5%). A1 and A2 had a gelation time of 40 minutes, and B1 and B2 had a gelation time of 30 minutes at 37°C. Electron micrographs revealed a three-dimensional internal structure with interconnected pores for the four types of hydrogels. This facilitates the exchange of nutrients, oxygen, and the exit of metabolites, allowing to preserve a microenvironment suitable for cell proliferation. In the infrared spectra, it was possible to observe the interaction that occurs between the amides of polymeric compounds with the phosphate groups of beta-glycerolphosphate. Finally, the biocompatibility tests indicated that cells in contact with the hydrogel or with each of its precursors are not affected in their proliferation capacity for a period of 16 days. These results show the potential of the hydrogel to increase the cell survival rate in the cardiac cell therapies under investigation. Moreover, the results lay the foundations for its characterization and biological evaluation in both in vitro and in vivo models.

Keywords: cardiac cell therapy, cardiac ischemia, natural polymers, thermosensitive hydrogel

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Authors: Naif Al-Jomah, Falah H Al-Mohanna, Abdelilah Aboussekhra

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Active breast cancer-associated fibroblasts (CAFs), the most influential cells in breast tumor microenvironment, express/secrete high levels of the proinvasive/metastatic interleukin-6 (IL-6). Therefore, we have tested here the effect of the IL-6 receptor (IL-6R) inhibitor tocilizumab (TCZ; Actemra) on different active breast CAFs. We have shown that TCZ potently and persistently suppresses the expression of various CAF biomarkers, namely α-SMA, SDF-1 as well as the STAT3 pathway and its downstream target AUF1. TCZ also inhibited the proliferation, migration and invasion abilities of active breast CAF cells. Additionally, TCZ repressed the ability of CAF cells in promoting epithelial-to-mesenchymal transition, and enhancing the migratory/invasive and proliferative capacities of breast cancer cells in vitro. Importantly, these findings were confirmed in orthotopic humanized breast tumors in mice. Furthermore, TCZ suppressed the expression of the pro-angiogenic factor VEGF-A and its transactivator HIF-1α in CAF cells, and consequently inhibited the angiogenic-promoting effect of active CAFs both in vitro and in orthotopic tumor xenografts. These results indicate that inhibition of the IL-6/STAT3/AUF1 pathway by TCZ can normalize active breast CAFs and suppress their paracrine pro-carcinogenic effects, which paves the way toward development of specific CAF-targeting therapy, badly needed for more efficient breast cancer treatments.

Keywords: angiogenesis, interleukin-6, paracrine, cancer-associated fibroblasts

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Authors: Prasanthi Malapati, R. Reshma, Vijay Soni, Perumal Yogeeswari, Dharmarajan Sriram

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In the present study, we attempted to develop Mycobacterium tuberculosis (Mtb) inhibitors by exploring the pharmaceutically underexploited enzyme targets which are majorly involved in cell wall biosynthesis of mycobacteria. For this purpose, glutamate racemase (coded by MurI gene) was selected. This enzyme racemize L-glutamate to D-glutamate required for the construction of peptidoglycan in the bacterial cell wall synthesis process. Furthermore this enzyme is neither expressed nor its product, D-glutamate is normally found in mammals, and hence designing inhibitors against this enzyme will not affect the host system as well act as potential antitubercular drugs. A library of BITS in house compounds were screened against Mtb MurI enzyme. Based on docking score, interactions and synthetic feasibility one hit lead was identified. Further optimization of lead was attempted and its derivatives were synthesized. Forty eight derivatives of 2-phenylbenzo[d]oxazole and 2-phenylbenzo[d]thiazole were synthesized and evaluated for Mtb MurI inhibition study, in vitro activities against Mtb, cytotoxicity against RAW 264.7 cell line. Chemical derivatization of the lead resulted in compounds NR-1213 AND NR-1124 as the potent M. tuberculosis glutamate racemase inhibitors with IC50 of 4-5µM which are remarkable and were found to be non-cytotoxic. Molecular dynamics, dormant models and cardiotoxicity studies of the most active molecules are in process.

Keywords: cell wall biosynthesis, dormancy, glutamate racemase, tuberculosis

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Authors: Syeda Kiran Shahzadi, Nasir Mahmood, Muhammad Abdul Qadir

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In the current research, three recombinant human interferon alpha-2b proteins (two modified and one normal form) were produced and Pegylated with an aim to produce more effective drugs against viral infections and cancers. The modified recombinant human interferon alpha-2b proteins were produced by site-directed modifications of interferon alpha 2b gene, targeting the amino acids at positions ‘R23’ and ‘H34’. The resulting chemically modified and unmodified forms of human interferon alpha 2b were conjugated with methoxy-polyethylene glycol propanealdehyde (400 KDa) and methoxy-polyethylene glycol succinimidyl succinate (400 KDa). Pegylation of normal and modified forms of Interferon alpha-2b prolong their release time and enhance their efficacy. The conjugation of PEG with modified and unmodified human interferon alpha 2b protein drugs was also characterized with 1H-NMR, HPLC, and SDS-PAGE. Antiproliferative assays of modified and unmodified forms of drugs were performed in cell based bioassays using MDBK cell lines. The results indicated that experimentally produced recombinant human interferon alpha-2b proteins were biologically active and resulted in significant inhibition of cell growth.

Keywords: protein refolding, antiproliferative activities, biomedical applications, human interferon alpha-2b, pegylation, mPEG-propionaldehyde, site directed mutagenesis, E. coli expression

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Authors: S. Nigri, R. Oumeddour, F. Djazi

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The inhibition of the corrosion of copper in 1 M HNO3 solution by oleic acid was investigated by weight loss measurement, potentiodynamic polarization and scanning electron microscope (SEM) studies. The experimental results have showed that this compound revealed a good corrosion inhibition and the inhibition efficiency is increased with the inhibitor concentration to reach 98%. The results obtained revealed that the adsorption of the inhibitor molecule onto metal surface is found to obey Langmuir adsorption isotherm. The temperature effect on the corrosion behavior of copper in 1 M HNO3 without and with inhibitor at different concentration was studied in the temperature range from 303 to 333 K and the kinetic parameters activation such as Ea, ∆Ha and ∆Sa were evaluated. Tafel plot analysis revealed that oleic acid acts as a mixed type inhibitor. SEM analysis substantiated the formation of protective layer over the copper surface.

Keywords: oleic acid, weight loss, electrochemical measurement, SEM analysis

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Authors: Tomáš Nejedlý, Dominika Mrázková, Jitka Viktorová

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The blood-brain barrier (BBB) serves as a protective shield, preventing the entry of harmful substances into the central nervous system. On the other hand, it also restricts the transport of neuroactive drugs, such as antiepileptics, which mitigate epileptic seizures. Drug-resistant epilepsy is often associated with the overexpression of efflux transporters, including P-glycoprotein (P-gp) or multidrug resistance protein 1 (MRP1), on the BBB. The aim of this work is to find P-gp and MRP1 inhibitors derived from phytocannabinoids and terpenes. The work evaluates whether these compounds interact directly with P-gp or MRP1 by rhodamine 123 or fluorescein efflux assay. The effect of phytocannabinoids on the gene expression of these transporters is also studied using qPCR and Western blot. These transporters are found in BBB cells; however, we decided to use the human ovarian cancer cell line (A2780ADR) due to its overproduction of P-gp and malignant glioma cell line (U87) due to its overproduction of MRP1. The results showed that while terpenes suppressed the activity of efflux transporters, phytocannabinoids tended to decrease their expression. Terpenes demonstrated an average inhibition of 65%, surpassing phytocannabinoids, which exhibited an average inhibition of approximately 30%. Particularly noteworthy was the modulating effect of (-)-α-bisabolol with the highest activity among the compounds tested. Based on these findings, phytocannabinoids and terpenes emerge as promising natural candidates for addressing drug resistance linked to efflux transporters. Acknowledgment: The project was funded by the Grant No 22-20860S of The Czech Science Foundation.

Keywords: drug-resistant epilepsy, efflux transporters, multidrug resistance protein 1, P-glycoprotein, phytocannabinoids, terpens

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Authors: Daniel Assefa, Engeda Dessalegn, Chetan Chauhan

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Moringa stenopetala is a socioeconomic valued tree that is widely available and cultivated in the Southern part of Ethiopia. The leaves have been traditionally used as a food source with high nutritional and medicinal values. The present work was carried out to evaluate the effect of thermal treatment on the total phenolic content, antioxidant and alpha-amylase inhibition activities of aqueous leaf extracts during maceration and different decoction time interval (5, 10 and 15 min). The total phenolic content was determined by the Folin-ciocalteu methods whereas antioxidant activities were determined by 2,2-diphenyl-1-picryl-hydrazyl(DPPH) radical scavenging, reducing power and ferrous ion chelating assays and alpha-amylase inhibition activity was determined using 3,5-dinitrosalicylic acid method. Total phenolic content ranged from 34.35 to 39.47 mgGAE/g. Decoction for 10 min extract showed ferrous ion chelating (92.52), DPPH radical scavenging (91.52%), alpha-amylase inhibition (69.06%) and ferric reducing power (0.765), respectively. DPPH, reducing power and alpha-amylase inhibition activities showed positive linear correlation (R2=0.853, R2= 0.857 and R2=0.930), respectively with total phenolic content but ferrous ion chelating activity was found to be weakly correlated (R2=0.481). Based on the present investigation, it could be concluded that major loss of total phenolic content, antioxidant and alpha-amylase inhibition activities of the crude leaf extracts of Moringa stenopetala leaves were observed at decoction time for 15 min. Therefore, to maintain the total phenolic content, antioxidant, and alpha-amylase inhibition activities of leaves, cooking practice should be at the optimum decoction time (5-10 min).

Keywords: alpha-amylase inhibition, antioxidant, Moringa stenopetala, total phenolic content

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Authors: Liang Jiansheng, Zhu Wei

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Light and brassinosteroids are essential external and internal cues for plant survival. Although the coordination of light with phytohormone signals is crucial for plant growth and development, the molecular connection between light and brassinosteroid signaling during root soil penetration remains elusive. Here, we reveal that light-stabilized RACK1 couples a brassinosteroid signaling cascade to drive cell division in root meristems. RACK1 family scaffold proteins positively regulate light-induced the promotion of root elongation during soil penetration. Under the light condition, RACK1A interacts with both phyB and SPA1, then reinforces the phyB-SPA1 association to accumulate its abundance in roots. In response to brassinosteroid signals, RACK1A competes with BKI1 to attenuate the BRI1-BKI1 interaction, thereby leading to activating BRI1 actions in root development. Furthermore, RACK1A binds to BES1 to repress its DNA binding activity toward the target gene CYCD3;1. This ultimately allows to release the inhibition of CYCD3;1 transcription, and promotes cell division during root growth. Our study illustrates a new mechanistic model of how plants engage scaffold proteins in transducing light information to facilitate brassinosteroid signaling for root growth in the soil.

Keywords: root growth, cell division, light signaling, brassinosteroid signaling, soil penetration, scaffold protein, RACK1

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Authors: Uche A. Nnawulezi

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This paper analyzes the advancing nature of nuclear terrorism and proliferation in the global environment and its attendant impacts. It analyzes discourse and practice with respect to the general prohibition on the utilization of fissionable radioactive materials. Thus, there has been a few ideological, reasonable and academic recommendations of policies aimed at eliminating nuclear weapons which its ultimate nightmare has remained an assault including nuclear explosion in densely populated urban areas. Likewise, this paper concentrates on safety measures aimed at preventing nuclear assaults which should not just concentrate on endeavors to prevent terrorists from exploding nuclear gadgets but should be more concerned on endeavors aimed at preventing the acquisition of nuclear weapons in the first place. The author of this paper has pointed out that the non-proliferation treaty should be vigorously supported as well as the Comprehensive Test Ban Treaty brought into force. This paper depended unequivocally on secondary sources, for example, textbooks, journals, articles, and periodicals. It concludes that the fundamental proposals made in this paper if completely used shall remain a cornerstone of efforts made in preventing the spread of nuclear weapons. At last, the only way is to eliminate stockpiles of nuclear weapons in the world or else the likelihood of nuclear terrorism remains a nightmare.

Keywords: nuclear, terrorism, proliferation, global environment

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Authors: Hye Kyung Kim, Myung-Gyou Kim, Kang-Hyun Leem

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Postmenopausal osteoporosis is characterized by low bone density which leads to increased bone fragility and greater susceptibility to fracture. Current treatments for osteoporosis are dominated by drugs that inhibit bone resorption although they also suppress bone formation that may contribute to pathogenesis of osteonecrosis. To restore the extensive bone loss, there is a great need for anabolic treatments that induce osteoblasts to build new bone. Pre-osteoblastic cells produce proteins of the extra-cellular matrix, including type I collagen at first, and then to successively produce alkaline phosphatase (ALP) and osteocalcin during differentiation to osteoblasts. Finally, osteoblasts deposit calcium. Present study investigated the effects of egg yolk peptide (EYP) on osteogenic activities and bone matrix gene expressions in human osteoblastic MG-63 cells. The effects of EYP on cell proliferation, alkaline phosphatase (ALP) activity, collagen synthesis, and mineralization were measured. The expression of osteogenic genes including COL1A1 (collagen, type I, alpha 1), ALP, BGLAP (osteocalcin), and SPP1 (secreted phosphoprotein 1, osteopontin) were measured by quantitative realtime PCR. EYP dose-dependently increased MG-63 cell proliferation, ALP activity, collagen synthesis, and calcium deposition. Furthermore, COL1A1, ALP, and SPP1 gene expressions were increased by EYP treatment. Present study suggested that EYP treatment enhanced osteogenic activities and increased bone matrix osteogenicgenes. These results could provide a mechanistic explanation for the bone-strengthening effects of EYP.

Keywords: egg yolk peptide, osteoblastic MG-63 cells, alkaline phosphatase, collagen synthesis, osteogenic genes, COL1A1, osteocalcin, osteopontin

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Authors: Marcela Dvorakova, Lenka Langhansova, Premysl Landa

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A series of quinazoline derivatives bearing aromatic rings in 2- and 4-positions were prepared and tested for their biological activity. Firstly, the compounds were evaluated for their potential to inhibit various kinases, such as autophagy activating kinase ULK1, 3-Phosphoinositide-dependent kinase 1, and TANK-binding kinase 1. None of the compounds displayed any activity on these kinases. Secondly, the compounds were tested for their anti-inflammatory activity expressed as cyclooxygenase (COX) isoforms and 5-lipoxygenase (5-LOX) inhibition. Three of the compounds showed significant selectivity towards COX-1 isoform (COX-2/COX-1 SI = 20-30). They inhibited COX-1 in a single-digit µM range. There was also one compound that exhibited inhibitory activity towards all three tested enzymes in µM range (IC50COX-1 = 1.9 µM; IC50COX-2 and 5-LOX = 10.1µM. COX-1 inhibition was until recently considered undesirable due to COX-1 constitutive expression in most cell types and tissues. Thus, there are not many compounds known with selective COX-1 activity. However, it is now believed that COX-1 plays an important role in the pathophysiology of several acute and chronic disorders, including cancer or neurodegenerative diseases. Thus, the discovery of effective COX-1 selective inhibitors is desirable and important.

Keywords: cyclooxygenases, kinases, lipoxygenases, quinazolines

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Authors: Gregory Chown, Benjamin Infantolino, Christopher Wise, Rachel Holmes, Samantha O'Donnell, Katelyn Pfeiffer, Victoria Ward

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Background: There is a lack of understanding of how Kinesio Tape® physiologically works. Furthermore, few studies compare Kinesio Tape® to other forms of taping. The research question is: Does Kinesio Tape® cause a difference in muscle facilitation, inhibition, and pain, between Kinesio Tape® and no tape for collegiate athletes with self-reported shoulder pain? Method: This quantitative non-randomized design used a convenience sampling method. There were eleven participants with self-reported shoulder pain who were athletes on the men’s and women’s lacrosse and tennis teams. Participants attended one 30-45 minute session for data collection. Each participant received all three taping conditions and performed four repetitions of 120 degrees of active shoulder flexion for the three separate trials (no tape, Kinesio Tape® inhibition, and Kinesio Tape® facilitation). Surface electromyography (sEMG) electrodes were placed on the anterior deltoid, supraspinatus, and lower trapezius to measure muscle facilitation and inhibition. Each participant completed the visual analogue scale (VAS) before and after each trial to measure pain. Results: No statistical significance was found for pain scores on the VAS between the taping methods of facilitation, inhibition, and no tape (p = .118). No statistical significance was found for the percentage of change in muscle function for each taping method; Anterior deltoid (p = .993), supraspinatus (p = .997) and lower trapezius (p = .922). Conclusion: Based on the results, Kinesio Tape® appears to not have an effect on muscle function or pain when utilizing the facilitation or inhibition taping method when compared to no tape.

Keywords: Kinesio tape, muscle facilitation, muscle inhibition, pain

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Authors: Roman Matejka, Vaclav Prochazka, Tibor Izak, Jana Stepanovska, Martina Travnickova, Alexander Kromka

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Cell-based impedance spectroscopy is suitable method for electrical monitoring of cell activity especially on substrates that cannot be easily inspected by optical microscope (without fluorescent markers) like decellularized tissues, nano-fibrous scaffold etc. Special sensor for this measurement was developed. This sensor consists of corning glass substrate with gold interdigitated electrodes covered with diamond layer. This diamond layer provides biocompatible non-conductive surface for cells. Also, a special PPFC flow cultivation chamber was developed. This chamber is able to fix sensor in place. The spring contacts are connecting sensor pads with external measuring device. Construction allows real-time live cell imaging. Combining with perfusion system allows medium circulation and generating shear stress stimulation. Experimental evaluation consist of several setups, including pure sensor without any coating and also collagen and fibrin coating was done. The Adipose derived stem cells (ASC) and Human umbilical vein endothelial cells (HUVEC) were seeded onto sensor in cultivation chamber. Then the chamber was installed into microscope system for live-cell imaging. The impedance measurement was utilized by vector impedance analyzer. The measured range was from 10 Hz to 40 kHz. These impedance measurements were correlated with live-cell microscopic imaging and immunofluorescent staining. Data analysis of measured signals showed response to cell adhesion of substrates, their proliferation and also change after shear stress stimulation which are important parameters during cultivation. Further experiments plan to use decellularized tissue as scaffold fixed on sensor. This kind of impedance sensor can provide feedback about cell culture conditions on opaque surfaces and scaffolds that can be used in tissue engineering in development artificial prostheses. This work was supported by the Ministry of Health, grants No. 15-29153A and 15-33018A.

Keywords: bio-impedance measuring, bioreactor, cell cultivation, diamond layer, gold interdigitated electrodes, tissue engineering

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Authors: Selena Ferrian, Erin Mccaffrey, Toshie Saito, Aiqin Cao, Noah Greenwald, Mark Robert Nicolls, Trevor Bruce, Roham T. Zamanian, Patricia Del Rosario, Marlene Rabinovitch, Michael Angelo

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Recent experimental and clinical observations are advancing immunotherapies to clinical trials in pulmonary arterial hypertension (PAH). However, comprehensive mapping of the immune landscape in pulmonary arteries (PAs) is necessary to understand how immune cell subsets interact to induce pulmonary vascular pathology. We used multiplexed ion beam imaging by time-of-flight (MIBI-TOF) to interrogate the immune landscape in PAs from idiopathic (IPAH) and hereditary (HPAH) PAH patients. Massive immune infiltration in I/HPAH was observed with intramural infiltration linked to PA occlusive changes. The spatial context of CD11c+DCs expressing SAMHD1, TIM-3 and IDO-1 within immune-enriched microenvironments and neutrophils were associated with greater immune activation in HPAH. Furthermore, CD11c-DC3s (mo-DC-like cells) within a smooth muscle cell (SMC) enriched microenvironment were linked to vessel score, proliferating SMCs, and inflamed endothelial cells. Experimental data in cultured cells reinforced a causal relationship between neutrophils and mo-DCs in mediating pulmonary arterial SMC proliferation. These findings merit consideration in developing effective immunotherapies for PAH.

Keywords: pulmonary arterial hypertension, vascular remodeling, indoleamine 2-3-dioxygenase 1 (IDO-1), neutrophils, monocyte-derived dendritic cells, BMPR2 mutation, interferon gamma (IFN-γ)

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Authors: Valeria Panzetta, Ida Musella, Sabato Fusco, Paolo Antonio Netti

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The study of the biophysics of living cells drew attention to the pivotal role of the cytoskeleton in many cell functions, such as mechanics, adhesion, proliferation, migration, differentiation and neoplastic transformation. In particular, during the complex process of malignant transformation and invasion cell cytoskeleton devolves from a rigid and organized structure to a more compliant state, which confers to the cancer cells a great ability to migrate and adapt to the extracellular environment. In order to better understand the malignant transformation process from a mechanical point of view, it is necessary to evaluate the direct crosstalk between the cells and their surrounding extracellular matrix (ECM) in a context which is close to in vivo conditions. In this study, human biopsy tissues of lung adenocarcinoma were analyzed in order to define their mechanical phenotype at cell and ECM level, by using particle tracking microrheology (PTM) technique. Polystyrene beads (500 nm) were introduced into the sample slice. The motion of beads was obtained by tracking their displacements across cell cytoskeleton and ECM structures and mean squared displacements (MSDs) were calculated from bead trajectories. It has been already demonstrated that the amplitude of MSD is inversely related to the mechanical properties of intracellular and extracellular microenvironment. For this reason, MSDs of particles introduced in cytoplasm and ECM of healthy and tumor tissues were compared. PTM analyses showed that cancerous transformation compromises mechanical integrity of cells and extracellular matrix. In particular, the MSD amplitudes in cells of adenocarcinoma were greater as compared to cells of normal tissues. The increased motion is probably associated to a less structured cytoskeleton and consequently to an increase of deformability of cells. Further, cancer transformation is also accompanied by extracellular matrix stiffening, as confirmed by the decrease of MSDs of matrix in tumor tissue, a process that promotes tumor proliferation and invasiveness, by activating typical oncogenic signaling pathways. In addition, a clear correlation between MSDs of cells and tumor grade was found. MSDs increase when tumor grade passes from 2 to 3, indicating that cells undergo to a trans-differentiation process during tumor progression. ECM stiffening is not dependent on tumor grade, but the tumor stage resulted to be strictly correlated with both cells and ECM mechanical properties. In fact, a greater stage is assigned to tumor spread to regional lymph nodes and characterized by an up-regulation of different ECM proteins, such as collagen I fibers. These results indicate that PTM can be used to get nanomechanical characterization at different scale levels in an interpretative and diagnostic context.

Keywords: cytoskeleton, extracellular matrix, mechanical properties, particle tracking microrheology, tumor

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Authors: H. Pegram, R. Stevens, L. De Girolamo

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Aligned electrospun nanofibres act as effective neuronal and glial cell scaffolds that can be layered to contain multiple sheets harboring different cell populations. This allows personalised biofunctional prostheses to be manufactured with both acellular and cellularised layers for the treatment of spinal cord injury. Additionally, the manufacturing route may be configured to produce in-vitro 3D cell based model of spinal cord injury to aid drug development and enhance prosthesis performance. The goal of this investigation was to optimise the multi-layer scaffold design parameters for prosthesis manufacture, to enable the development of multi-layer patient specific implant therapies. The work has also focused on the fabricating aligned nanofibre scaffolds that promote in-vitro neuronal and glial cell population growth, cell-to-cell interaction and long-term survival following trauma to mimic an in-vivo spinal cord lesion. The approach has established reproducible lesions and has identified markers of trauma and regeneration marked by effective neuronal migration across the lesion with glial support. The investigation has advanced the development of an in-vitro model of traumatic spinal cord injury and has identified a route to manufacture prostheses which target the repair spinal cord injury. Evidence collated to investigate the multi-layer concept suggests that physical cues provided by nanofibres provide both a natural extra-cellular matrix (ECM) like environment and controls cell proliferation and migration. Specifically, aligned nanofibre layers act as a guidance system for migrating and elongating neurons. On a larger scale, material type in multi-layer systems also has an influence in inter-layer migration as cell types favour different material types. Results have shown that layering nanofibre membranes create a multi-level scaffold system which can enhance or prohibit cell migration between layers. It is hypothesised that modifying nanofibre layer material permits control over neuronal/glial cell migration. Using this concept, layering of neuronal and glial cells has become possible, in the context of tissue engineering and also modelling in-vitro induced lesions.

Keywords: electrospinning, layering, lesion, modeling, nanofibre

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Authors: Huseyin Apdik, Aysegul Dogan, Selami Demirci, Ezgi Avsar Apdik, Fikrettin Sahin

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Mesenchymal stem cells (MSCs) are crucial cell types for bone maintenance and growth along with resident bone progenitor cells providing bone tissue integrity during osteogenesis and skeletal growth. Any deficiency in this regulation would result in vital bone diseases. Of those, osteoporosis, characterized by a reduction in bone mass and mineral density, is a critical skeletal disease for especially elderly people. The commonly used drugs for the osteoporosis treatment are bisphosphonates (BPs). The most prominent role of BPs is to prevent bone resorption arisen from high osteoclast activity. However, administrations of bisphosphonates may also cause bisphosphonate-induced osteonecrosis of the jaw (BIONJ). Up to the present, the researchers have proposed several circumstances for BIONJ. However, effects of long-term and/or high dose usage of BPs on stem cell’s proliferation, survival, differentiation or maintenance capacity have not been evaluated yet. The present study will be held to; figure out BPs’ effects on MSCs in vitro in the aspect of cell proliferation and toxicity, migration, angiogenic activity, lineage specific gene and protein expression levels, mesenchymal stem cell properties and potential signaling pathways affected by BP treatment. Firstly, mesenchymal stem cell characteristics of Dental Pulp Stem Cells (DPSCs) and Periodontal Ligament Stem Cells (PDLSCs) were proved using flow cytometry analysis. Cell viability analysis was completed to determine the cytotoxic effects of BPs (Zoledronate (Zol), Alendronate (Ale) and Risedronate (Ris)) on DPSCs and PDLSCs by the 3-(4,5-di-methyl-thiazol-2-yl)-5-(3-carboxymethoxy-phenyl)-2-(4-sulfo-phenyl)-2H-tetrazolium (MTS) assay. Non-toxic concentrations of BPs were determined at 24 h under growth condition, and at 21 days under osteogenic differentiation condition for both cells. The scratch assay was performed to evaluate their migration capacity under the usage of determined of BPs concentrations at 24 h. The results revealed that while the scratch closure is 70% in the control group for DPSCs, it was 57%, 66% and 66% in Zol, Ale and Ris groups, respectively. For PDLSs, while wound closure is 71% in control group, it was 65%, 66% and 66% in Zol, Ale and Ris groups, respectively. As future experiments, tube formation assay and aortic ring assay will be done to determinate angiogenesis abilities of DPSCs and PDLSCs treated with BPs. Expression levels of osteogenic differentiation marker genes involved in bone development will be determined using real time-polymerase change reaction (RT-PCR) assay and expression profiles of important proteins involved in osteogenesis will be evaluated using western blotting assay for osteogenically differentiated MSCs treated with or without BPs. In addition to these, von Kossa staining will be performed to measure calcium mineralization status of MSCs.

Keywords: bisphosphonates, bisphosphonate-induced osteonecrosis of the jaw, mesenchymal stem cells, osteogenesis

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Authors: Tannaz Alimardani, Amirhossein Moghanian, Morteza Elsa

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Bioactive glasses (BGs) are a group of surface-reactive biomaterials used in clinical applications as implants or filler materials in the human body to repair and replace diseased or damaged bone. Sol-gel technique was employed to prepare a SiO₂-CaO-P₂O₅ glass with a nominal composition of 58S BG with the addition of Sr and Li modifiers which imparts special properties to the BG. The effect of simultaneous addition of Sr and Li on bioactivity and biocompatibility, proliferation, alkaline phosphatase (ALP) activity of osteoblast cell line MC3T3-E1 and antibacterial property against methicillin-resistant Staphylococcus aureus (MRSA) bacteria were examined. BGs were characterized by X-ray diffraction, Fourier transform infrared spectroscopy and scanning electron microscopy before and after soaking the samples in the simulated body fluid (SBF) for different time intervals to characterize the formation of hydroxyapatite (HA) formed on the surface of BGs. Structural characterization indicated that the simultaneous presence of 5% Sr and 5% Li in 58S-BG composition not only did not retard HA formation because of the opposite effect of Sr and Li of the dissolution of BG in the SBF, but also stimulated the differentiation and proliferation of MC3T3-E1s. Moreover, the presence of Sr and Li on the dissolution of the ions resulted in an increase in the mean number of DAPI-labeled nuclei which was in good agreement with the live/dead assay. The result of antibacterial tests revealed that Sr and Li-substituted 58S bioactive glass exhibited a potential antibacterial effect against MRSA bacteria. Because of optimal proliferation and ALP activity of MC3T3-E1cells, proper bioactivity and high antibacterial potential against MRSA, BG-5/5 is suggested as a multifunctional candidate for bone tissue engineering.

Keywords: alkaline, alkaline earth, bioglass, co-doping, ion release

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Authors: Isha Ranadive, Sonam Patel, Suresh Balakrishnan

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It has been observed that in lizards wound can be healed by either a scar free mechanism or by scarring. The animal model used to study both these healing processes was Northern House Gecko. In lizard, the tail when amputated heals by scar free mechanism which allows it to regenerate, the same is not seen when the limb is amputated. Proliferation, apoptosis, and angiogenesis are the main events which succeed an injury. We observed that proliferation of the cells beneath the wound epidermis was much higher in case of wound healing in tail. This could be because after the wound gets covered by the epithelium, it enters in to a cross-talk with the underlying mesenchyme to recruit a pool of blastemal cells which proliferate and later differentiate to form the lost part through epimorphic regeneration. This was substantiated by mRNA expression levels of various FGFs which facilitate the cross-talk and also by PCNA which is a marker for proliferation. Western blot result reaffirms the same notion. However, in case of the limb, the rate of apoptosis was more than proliferation as there are a lot of debris that needs to be removed. We came to this conclusion as we observed that p53 the apoptotic gene was highly upregulated in case of the scarred tissue. Further, we confirmed this result by checking the anti-apoptotic gene bcl2 and found it to be significantly down-regulated. As we noticed heightened proliferation in the case of scar-free wound healing in tail, angiogenesis was targeted for the study. This is because, when the cells are proliferating they require constant supply of blood and hence neo-vascularization is inevitable. It was observed that the marker of angiogenesis, VEGF, was expressed more during wound healing as compared to the resting stage of tail. Moreover, a high up-regulation was seen in KDR, a receptor of VEGF. Thus, this study reveals how proliferation, apoptosis, and angiogenesis play a key role in the scar-free as well as scarred wound healing.

Keywords: epimorphic regeneration, injury, northern house gecko, wound healing

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Authors: Rashmi Gupta

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It is unclear whether arousal or valence modulates the response inhibition process. It has been suggested that irrelevant positive emotional information (e.g., happy faces) and negative emotional information (e.g., angry faces) interact with attention differently. In the present study, we used arousal-matched irrelevant happy and angry faces. These faces were used as stop-signals in the stop-signal paradigm. There were two kinds of trials: go-trials and stop-trials. Participants were required to discriminate between the letter X or O by pressing the corresponding keys on go-trials. However, a stop signal was occasionally presented on stop trials, where participants were required to withhold their motor response. A significant main effect of emotion on response inhibition was observed. It indicated that the valence of a stop signal modulates inhibitory control. We found that stop-signal reaction time was faster in response to irrelevant angry faces than happy faces, indicating that irrelevant angry faces facilitate the response inhibition process compared to happy faces. These results shed light on the interaction of emotion with cognitive control functions.

Keywords: attention, emotion, response inhibition, inhibitory control

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Authors: Chih-Wei Chao, Jiashing Yu

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Microfluidic devices have recently emerged as promising tools for the fabrication of scaffolds for cell culture. To mimic the natural circumstances of organism for cells to grow, here we present three-dimensional (3D) scaffolds fabricated by microfluidics for cells cultivation. This work aims at investigating the behavior in terms of the viability and the proliferation capability of rat H9c2 cardiomyocytes in the gelatin 3D scaffolds by fluorescent images.

Keywords: microfluidic device, H9c2, tissue engineering, 3D scaffolds

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Authors: Kitti Szoke, Laszlo Szoke, Attila Czompa, Arpad Tosaki, Istvan Lekli

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Autophagy plays an important role in cardiac hypertrophy, which is one of the most common causes of heart failure in the world. This self-degradative catabolic process, responsible for protein quality control, balancing sources of energy at critical times, and elimination of damaged organelles. The autophagic activity can be triggered by starvation, oxidative stress, or pharmacological agents, like rapamycin. This induced autophagy can promote cell survival during starvation or pathological stress. In this study, it is investigated the effect of the induced autophagic process on angiotensin induced hypertrophic H9c2 cells. In our study, it is used H9c2 cells as an in vitro model. To induce hypertrophy, cells were treated with 10000 nM angiotensin-II, and to activate autophagy, 100 nM rapamycin treatment was used. The following groups were formed: 1: control, 2: 10000 nM AT-II, 3: 100 nM rapamycin, 4: 100 nM rapamycin pretreatment then 10000 nM AT-II. The cell viability was examined via MTT (cell proliferation assay) assay. The cells were stained with rhodamine-conjugated phalloidin and DAPI to visualize F-actin filaments and cell nuclei then the cell size alteration was examined in a fluorescence microscope. Furthermore, the expression levels of autophagic and apoptotic proteins such as Beclin-1, p62, LC3B-II, Cleaved Caspase-3 were evaluated by Western blot. MTT assay result suggests that the used pharmaceutical agents in the tested concentrations did not have a toxic effect; however, at group 3, a slight decrement was detected in cell viability. In response to AT-II treatment, a significant increase was detected in the cell size; cells became hypertrophic. However, rapamycin pretreatment slightly reduced the cell size compared to group 2. Western blot results showed that AT-II treatment-induced autophagy, because the increased expression of Beclin-1, p62, LC3B-II were observed. However, due to the incomplete autophagy, the apoptotic Cleaved Caspase-3 expression also increased. Rapamycin pretreatment up-regulated Beclin-1 and LC3B-II, down-regulated p62 and Cleaved Caspase-3, indicating that rapamycin-induced autophagy can restore the normal autophagic flux. Taken together, our results suggest that rapamycin activated autophagy reduces angiotensin-II induced hypertrophy.

Keywords: angiotensin-II, autophagy, H9c2 cell line, hypertrophy, rapamycin

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Authors: Bernard L. Middleton, Susan P. Cosgrove

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There is an immediate need for alternative anti-herpetic treatment options effective for both primary infections and reoccurring reactivations of herpes simplex virus types 1 (HSV-1) and 2 (HSV-2). Alternatives currently approved for the purposes of clinical administration includes antivirals and a reduced set of nucleoside analogues. The present article tests a treatment based on a systemic understanding of how the herpes virus affects cell inhibition and breakdown and targets different phases of the viral cycle, including the entry stage, reproductive cross mutation, and cell-to-cell infection. The treatment consisted of five immunotherapeutic core compounds (5CC), which were hypothesized to be capable of neutralizing human monoclonal antibodies. The tested 5CC were noted as being functional in the application of eliminating the DNA synthesis of herpes viral interferon (IFN) - induced cellular antiviral response. They were here found to neutralize antiviral reproduction by blocking cell-to-cell infection. The activity of the 5CC was tested on RC-37 in vitro using an assay plaque reduction and in vivo against HSV-1 and HSV-2. The 50% inhibitory concentration (IC50) of 5CC was 0.0009% for HSV-1 plaque formation and 0.0008% for HSV-2 plaque formation. Further tests were performed to evaluate the susceptibility of HSV-1 and HSV-2 to anti-herpetic drugs in Vero cells after virus entry. There were high-level markers of the 5CC virucidal activity in the viral suspension of HSV-1 and HSV-2. These concentrations of the 5CC are nontoxic and reduced plaque formation by 98.2% for HSV-1 and 93.0% for HSV-2. Virus HSV-1 and HSV-2 titers were reduced significantly by 5CC to the point of being negative, ranging 0.01–0.09 in 72%. The results concluded the 5CC as being an effective treatment option for the herpes simplex virus.

Keywords: synergy pharmaceuticals, herpes treatment, herpes cure, synergy pharmaceuticals treatment

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Authors: T. Büyüksırıt, H. Kuleaşan

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Natural antimicrobials are used to preserve foods that can be found in plants, animals, and microorganisms. Antimicrobial substances are natural or artificial agents that produced by microorganisms or obtained semi/total chemical synthesis are used at low concentrations to inhibit the growth of other microorganisms. Food borne pathogens and spoilage microorganisms are inactivated by the use of antagonistic microorganisms and their metabolites. Yeasts can produce toxic proteins or glycoproteins (toxins) that cause inhibition of sensitive bacteria and yeast species. Antimicrobial substance producing phenotypes belonging different yeast genus were isolated from different sources. Toxins secreted by many yeast strains inhibiting the growth of other yeast strains. These strains show antimicrobial activity, inhibiting the growth of mold and bacteria. The effect of antimicrobial agents produced by yeasts can be extremely fast, and therefore may be used in various treatment procedures. Rapid inhibition of microorganisms is possibly caused by microbial cell membrane lipopolysaccharide binding and in activation (neutralization) effect. Antimicrobial agents inhibit the target cells via different mechanisms of action.

Keywords: antimicrobial agents, yeast, toxic protein, glycoprotein

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Authors: Svitlana Antonenko, Gennady Telegeev

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Introductive statement: The development of chronic myeloid leukemia (CML) is caused by Bcr-Abl oncoprotein. Modern treatments with tyrosine kinase inhibitors are greatly complicated by the mutational variability of the Bcr-Abl oncoprotein, which causes drug resistance. Therefore, there is an urgent need to develop new approaches to the treatment of the disease, which will allow modeling the level of Bcr-Abl oncoprotein in the cell. Promising in this direction is the identification of proteases that can selectively promote cellular proteolysis of oncoproteins. The aim of the study was to study the effect of the interaction of Bcr-Abl with deubiquitinase USP1 on the level of oncoprotein in CML cells. Methodology: K562 cells were selected for the experiment. Сells were incubated with ML323 inhibitor for 24 hours. Precipitation of endogenous proteins from K562 cell lysate was performed using anti-Bcr-Abl antibodies. Cell lysates and precipitation results were studied by Western blot. Subcellular localization of proteins was studied by immunofluorescence analysis followed by confocal microscopy. The results were analyzed quantitatively and statistically. Major findings: The Bcr-Abl/USP1 protein complex was detected in CML cells, and it was found that inhibition of USP1 deubiquitinating activity by the compound ML323 leads to disruption of this protein complex and a decrease in the level of Bcr-Abl oncoprotein in cells. The interaction of Bcr-Abl with USP1 may result in deubiquitination of the oncoprotein, which disrupts its proteasomal degradation and leads to the accumulation of CML in cells. Conclusion: We believe that the interaction of oncoprotein with USP1 may be one of the prerequisites that contribute to malignant cell transformation due to the deubiquitination of oncoprotein, which leads to its accumulation and disease progression. A correlation was found between the deubiquitinating activity of USP1 and the level of oncoprotein in CML cells. Thus, we identify deubiquitinase USP1 as a promising therapeutic target for the development of a new strategy for the treatment of CML by modulating the level of Bcr-Abl in the cell.

Keywords: chronic myeloid leukemia, Bcr-Abl, USP1, deubiquitination Bcr-Abl, K562 cell

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