Modulators of Prostate Cancer Cell Proliferation and Viability Identified by Short-Hairpin RNA Library Screening
Ontology highlight
ABSTRACT:
ORGANISM(S): Homo sapiens
PROVIDER: GSE32261 | GEO | 2012/08/31
SECONDARY ACCESSION(S): PRJNA147341
REPOSITORIES: GEO
Similar Datasets
Project description:Recovery of hairpins targeting a known prostate cancer pathway testing the utility of shRNA library screening in prostate cancer as a broad strategy to identify new candidate drug targets. Two cell lines assayed for 4 time points with a control and 2 experimental conditions. Two to four replicates of each instance are provided.
2012-08-31 | E-GEOD-32261 | biostudies-arrayexpress
Project description:There is significant need to identify novel prostate cancer drug targets because current hormone therapies eventually fail, leading to a drug-resistant and fatal disease termed castration-resistant prostate cancer. To functionally identify genes that, when silenced, decrease prostate cancer cell proliferation or induce cell death in combination with antiandrogens, we employed an RNA interference-based short hairpin RNA barcode screen in LNCaP human prostate cancer cells. We identified and validated four candidate genes (AKT1, PSMC1, STRADA, and TTK) that impaired growth when silenced in androgen receptor positive prostate cancer cells and enhanced the antiproliferative effects of antiandrogens. Inhibition of AKT with a pharmacologic inhibitor also induced apoptosis when combined with antiandrogens, consistent with recent evidence for PI3K and AR pathway crosstalk in prostate cancer cells. Recovery of hairpins targeting a known prostate cancer pathway validates the utility of shRNA library screening in prostate cancer as a broad strategy to identify new candidate drug targets.
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Project description:To obtain a whole genome library that suppresses the total diversity of human mRNAs, lentiviral vector constructs and a short hairpin RNA (shRNA) expression cassette were optimized. The optimization of the vector increased the virus titer in preparations by 15-20 times. A simple shRNA structure with a 21-bp stem proved to be the most effective. Lentivector-based shRNA expression constructs were obtained by using puro(R), copGFP, or H-2K(k) as a selectable marker. The efficiency of the optimized library was demonstrated when screening for shRNAs reactivating the tumor suppressor p53 in HeLa cells. Cells carried a reporter construct ensuring p53-responsive synthesis of a fluorescent protein, which allowed selection of cells with reactivated p53 by flow cytometry.
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