Hyunseung Lee

Publications

1 Cryptanalysis of Two-Factor Authenticated Key Exchange Protocol in Public Wireless LANs

Authors: Donghyun Choi, Yunho Lee, Dongho Won, Seungjoo Kim, Hyunseung Lee

Abstract:

In Public Wireless LANs(PWLANs), user anonymity is an essential issue. Recently, Juang et al. proposed an anonymous authentication and key exchange protocol using smart cards in PWLANs. They claimed that their proposed scheme provided identity privacy, mutual authentication, and half-forward secrecy. In this paper, we point out that Juang et al.'s protocol is vulnerable to the stolen-verifier attack and does not satisfy user anonymity.

Keywords: Authentication, User Privacy, smart card, key exchange, PWLANs

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1048

Abstracts

2 An Activatable Theranostic for Targeted Cancer Therapy and Imaging

Authors: Hyunseung Lee, Eun-Joong Kim, Sankarprasad Bhuniya, Kwan Soo Hong, Jong Seung Kim, Sukhendu Maiti, Jonathan L. Sessler

Abstract:

A new theranostic strategy is described. It is based on the use of an “all in one” prodrug, namely the biotinylated piperazine-rhodol conjugate 4a. This conjugate, which incorporates the anticancer drug SN-38, undergoes self-immolative cleavage when exposed to biological thiols. This leads to the tumor-targeted release of the active SN-38 payload along with fluorophore 1a. This release is made selective as the result of the biotin functionality. Fluorophore 1a is 32-fold more fluorescent than prodrug 4a. It permits the delivery and release of the SN-38 payload to be monitored easily in vitro and in vivo, as inferred from cell studies and ex vivo analyses of mice xenografts derived HeLa cells, respectively. Prodrug 4a also displays anticancer activity in the HeLa cell murine xenograft tumor model. On the basis of these findings we suggest that the present strategy, which combines within a single agent the key functions of targeting, release, imaging, and treatment, may have a role to play in cancer diagnosis and therapy.

Keywords: Cancer Therapy, Fluorescence, Theranostic, prodrug

Procedia PDF Downloads 370
1 An Activatable Prodrug for the Treatment of Metastatic Tumors

Authors: Hyunseung Lee, Eun-Joong Kim, Sankarprasad Bhuniya, Hyun Min Kim, Chaejoon Cheong, Su-khendu Maiti, Kwan Soo Hong, Jong Seung Kim

Abstract:

Metastatic cancers have historically been difficult to treat. However, metastatic tumors have been found to have high levels of reactive oxygen species such as hydrogen peroxide (H2O2), supporting the hypothesis that a prodrug could be activated by intracellular H2O2 and lead to a potential anti-metastatic therapy. In this study, prodrug 7 was designed to be activated by H2O2-mediated boronate oxidation, resulting in activation of the fluorophore for detection and release of the therapeutic agent, SN-38. Drug release from prodrug 7 was investigated by monitoring fluorescence after addition of H2O2 to the cancer cells. Prodrug 7 activated by H2O2 selectively inhibited tumor cell growth. Furthermore, intratracheally administered prodrug 7 showed effective anti-tumor activity in a mouse model of metastatic lung disease. Thus, this H2O2-responsive prodrug has therapeutic potential as a novel treatment for metastatic cancer via cellular imaging with fluorescence as well as selective release of the anti-cancer drug, SN-38.

Keywords: Fluorescence, Hydrogen Peroxide, prodrug, metastatic tumors

Procedia PDF Downloads 294