title: Cathepsin L in tumor angiogenesis and its therapeutic intervention by the small molecule inhibitor KGP94.
abstract: A significant proportion of breast cancer patients harbor clinically undetectable micrometastases at the time of diagnosis. If left untreated, these micro-metastases may lead to disease relapse and possibly death. Hence, there is significant interest in the development of novel anti-metastatic agents that could also curb the growth of pre-established micrometastases. Like primary tumor, the growth of metastases also is driven by angiogenesis. Although the role of cysteine protease Cathepsin L (CTSL) in metastasis associated tumor cell functions such as migration and invasion is well recognized, its role in tumor angiogenesis remains less explored. The present study examines the contribution of CTSL to breast cancer angiogenesis and evaluates the anti-angiogenic efficacy of CTSL inhibitor KGP94. CTSL semi-quantitative RT-PCR analysis on breast tissue panels revealed significant upregulation of CTSL in breast cancer patients which strongly correlated with increased relapse and metastatic incidence and poor overall survival. Preclinically, CTSL ablation using shRNA or KGP94 treatment led to a significant reduction in MDA-MB-231 tumor cell induced angiogenesis in vivo. In-vitro assessments demonstrated a significant decrease in various angiogenic properties such as endothelial cell sprouting, migration, invasion, tube formation and proliferation in the presence of KGP94. Microarray analyses revealed a significant upregulation of cell cycle related genes by CTSL. Western blot analyses further confirmed upregulation of members of the cyclin family by CTSL. Collectively, these data indicate that CTSL is an important contributor to tumor angiogenesis and that the CTSL inhibition may have therapeutic utility in the treatment of breast cancer patients.
authors.affiliation: Department of Radiation Oncology, University of Florida Health Cancer Center, Gainesville, USA. dhivyasudhan@ufl.edu.|Cancer and Genetics Research Complex, University of Florida Health Cancer Center, Room 485E, Gainesville, FL, 32610, USA. dhivyasudhan@ufl.edu.
authors.forename: Dhivya R
authors.initials: DR
authors.lastname: Sudhan
authors.affiliation: CEPROCOR, National Scientific and Technical Research Council (CONICET), Córdoba, Argentina.
authors.forename: Maria B
authors.initials: MB
authors.lastname: Rabaglino
authors.affiliation: Department of Physiology and Functional Genomics, College of Medicine, University of Florida, Gainesville, USA.
authors.forename: Charles E
authors.initials: CE
authors.lastname: Wood
authors.affiliation: Department of Radiation Oncology, University of Florida Health Cancer Center, Gainesville, USA.|Department of Pharmacology and Therapeutics, College of Medicine, University of Florida, Gainesville, USA.
authors.forename: Dietmar W
authors.initials: DW
authors.lastname: Siemann
mesh_terms: D000328:Adult; D000368:Aged; D001943:Breast Neoplasms / Q000188:drug therapy* / Q000235:genetics / Q000473:pathology; D056668:Cathepsin L / Q000037:antagonists & inhibitors / Q000235:genetics*; D045744:Cell Line, Tumor; D002465:Cell Movement / Q000187:drug effects; D005260:Female; D061307:Human Umbilical Vein Endothelial Cells; D006801:Humans; D008875:Middle Aged; D009361:Neoplasm Invasiveness / Q000473:pathology / Q000517:prevention & control; D061206:Neoplasm Micrometastasis / Q000188:drug therapy* / Q000235:genetics / Q000473:pathology; D009364:Neoplasm Recurrence, Local / Q000188:drug therapy / Q000235:genetics / Q000473:pathology; D009389:Neovascularization, Pathologic / Q000188:drug therapy* / Q000235:genetics / Q000473:pathology; D013882:Thiosemicarbazones / Q000008:administration & dosage; D013890:Thiourea / Q000008:administration & dosage / Q000031:analogs & derivatives
chemical_list: C581086:KGP94; D013882:Thiosemicarbazones; D056668:Cathepsin L; D013890:Thiourea
keywords: Angiogenesis; Breast cancer; Cathepsin L; KGP94