A Pharmacologic Inhibitor of the Protease Taspase1 Effectively Inhibits Breast and Brain Tumor Growth

作者:Chen David Y; Lee Yishan; Van Tine Brian A; Searleman Adam C; Westergard Todd D; Liu Han; Tu Ho Chou; Takeda Shugaku; Dong Yiyu; Piwnica Worms David R; Oh Kyoung J; Korsmeyer Stanley J; Hermone Ann; Gussio Richard; Shoemaker Robert H; Cheng Emily H Y; Hsieh James J D*
来源:Cancer Research, 2012, 72(3): 736-746.
DOI:10.1158/0008-5472.CAN-11-2584

摘要

The threonine endopeptidase Taspase1 has a critical role in cancer cell proliferation and apoptosis. In this study, we developed and evaluated small molecule inhibitors of Taspase1 as a new candidate class of therapeutic modalities. Genetic deletion of Taspase1 in the mouse produced no overt deficiencies, suggesting the possibility of a wide therapeutic index for use of Taspase1 inhibitors in cancers. We defined the peptidyl motifs recognized by Taspase1 and conducted a cell-based dual-fluorescent proteolytic screen of the National Cancer Institute diversity library to identify Taspase1 inhibitors (TASPIN). On the basis of secondary and tertiary screens the 4-[(4-arsonophenyl) methyl] phenyl] arsonic acid NSC48300 was determined to be the most specific active compound. Structure-activity relationship studies indicated a crucial role for the arsenic acid moiety in mediating Taspase1 inhibition. Additional fluorescence resonance energy transfer-based kinetic analysis characterized NSC48300 as a reversible, noncompetitive inhibitor of Taspase1 (Ki 4.22 mmol/ L). In the MMTV-neu mouse model of breast cancer and the U251 xenograft model of brain cancer, NSC48300 produced effective tumor growth inhibition. Our results offer an initial preclinical proof-of-concept to develop TASPINs for cancer therapy. Cancer Res; 72(3); 736-46.

  • 出版日期2012-2-1