TY  - JOUR
T1  - Identification of Small-Molecule Inhibitors of the Colorectal Cancer Oncogene Krüppel-Like Factor 5 Expression by Ultrahigh-Throughput Screening
LA  - en
YR  - 2011
UL  - http://buscaintegrada.pucsp.br/vufind/Record/pubmed-3213326
AB  - The transcription factor Krüppel-like factor 5 (KLF5) is primarily expressed in the proliferative zone of the mammalian intestinal epithelium where it regulates cell proliferation. Studies showed that inhibition of KLF5 expression reduces proliferation rates in human colorectal cancer cells and intestinal tumor formation in mice. To identify chemical probes that decrease levels of KLF5, we used cell-based ultrahigh-throughput screening (uHTS) to test compounds in the NIH’s public domain, the Molecular Libraries Probe Production Centers Network (MLPCN) library. The primary screen involved luciferase assays in the DLD-1/pGL4.18hKLF5p cell line, which stably expressed a luciferase reporter driven by the human KLF5 promoter. A cytotoxicity counterscreen was performed in the rat intestinal epithelial cell line, IEC-6. We identified 97 KLF5-selective compounds with EC(50)<10 µM for KLF5 inhibition and EC(50)>10 µM for IEC-6 cytotoxicity. The two most potent compounds, CIDs (PubChem Compound IDs) 439501 and 5951923, were further characterized based on computational, Western blot, and cell viability analyses. Both of these compounds and two newly-synthesized structural analogs of CID 5951923 significantly reduced endogenous KLF5 protein levels and decreased viability of several colorectal cancer cell lines without any apparent impact on IEC-6 cells. Finally, when tested in the NCI-60 panel of human cancer cell lines, compound CID 5951923 was selectively active against colon cancer cells. Our results demonstrate the feasibility of uHTS in identifying novel compounds that inhibit colorectal cancer cell proliferation by targeting KLF5.
KW  - Article
ER  -