Project description:Identification and validation of NOL5A and RPS2 as potential therapeutic targets in colorectal cancer using a functional genomics approach. To identify potential therapeutic targets for colorectal cancer, we first assessed the functional and molecular consequences of RNAi mediated silencing of candidate genes derived from previously performed gene expression analyses. We then generated gene expression signatures after RNAi against HMGA1, RRM2, TACSTD2, RPS2, and NOL5A.
Project description:Identification and validation of NOL5A and RPS2 as potential therapeutic targets in colorectal cancer using a functional genomics approach. To identify potential therapeutic targets for colorectal cancer, we first assessed the functional and molecular consequences of RNAi mediated silencing of candidate genes derived from previously performed gene expression analyses. We then generated gene expression signatures after RNAi against HMGA1, RRM2, TACSTD2, RPS2, and NOL5A. To assess the consequences of silencing specific genes on global gene expression levels, triplicate transfections were independently performed. Cells for lyzed 48 hours or 72 hours after transfection (depending on the target gene), and total RNA was isolated for each transfection. For each sample, one array experiment was subsequently performed.
Project description:<p>BRCA1 mutations are a hallmark of hereditary ovarian cancer, strongly linked to deficiencies in homologous recombination (HR) DNA repair and impaired DNA replication fork protection. However, its roles in cancer progression beyond maintaining genomic integrity remain poorly understood. Through metabolomics approaches, we found BRCA1-deficiency strikingly increased choline metabolism. Loss of BRCA1 promotes choline uptake through upregulating choline transporter-like protein 4 (CTL4). BRCA1 directly binds and recruits EZH2-mediated H3K27Me3 deposition to CTL4 promoter. CTL4 was therefore overexpressed in ovarian cancer tissues with BRCA1 mutations. Furthermore, BRCA1-deficiency significantly promotes ovarian cancer invasion, while inhibition of CTL4 reverses the high metastatic potential of BRCA1-deficient ovarian cancer cells, suggesting the functionality and specificity of CTL4 as a therapeutic target. Additionally, we discovered that phosphocholine, the choline metabolite increased by CTL4 overexpression, interacted with and stabilized the epithelial-to-mesenchymal transition inducer FAM3C in BRCA1-deficient ovarian cancer cells. Importantly, we identified a potent CTL4 inhibitor, DT-13, which significantly reduces choline metabolism and effectively suppresses metastasis in BRCA1-deficient ovarian cancers. Therefore, our study uncovers a mechanism underlying metastasis in BRCA1-deficient cancers and identifies CTL4 as a therapeutic target for metastatic ovarian cancer patients with BRCA1 mutations.</p>
