Project description:Sprouty proteins are evolutionarily conserved modulators of mitogen-activated protein kinase pathway. Sprouty2 appears to function as a tumor suppressor in cancers, whereas we reported earlier that Sprouty2 functions as an oncogene in colorectal cancer. To further understand the oncogenic potential of Sprouty2 in the colon, microRNA expression profile of colon cancer cells was investigated. Sprouty2 suppression in HCT116 colon cancer cells significantly increased MicroRNA 194-5p. Sprouty2 dependent regulation of microRNA194-5p and its biological targets were studied further for their tumor suppressive actions in reducing epithelial-mesenchymal transition in colorectal cancer.
Project description:Colorectal cancer (CRC) with high rate of mortality is one of the most commonly diagnosed cancers in worldwide. Advanced colorectal cancer is often accompanied by malignant proliferation of tumor cells. Further researches on colorectal cancer proliferation to find new targets and develop new therapeutic regimen are an important direction for colorectal cancer treatment. In this study, genome-wide RNAi screening was used to discover the essential genes associated with colorectal cancer cell proliferation. We found DKC1 (dyskerin pseudouridine synthase 1) promoted CRC proliferation through binding and modifying ribosomal proteins (RPL10A, RPL22L1, RPL34, RPS3) mRNA to increase the mRNAs stability and eventually increasing their expression. Besides, DKC1 is highly expressed in colorectal cancer and its aberrantly high expression is associated with poor prognosis of colorectal cancer patients. These results suggest that DKC1 could be a new therapeutic target for colorectal cancer.
Project description:We experimentally demonstrated that CHD7 promotes the growth of colorectal cancer cells in vitro and in vivo. Mechanistically, RNA-seq and ATAC-seq approaches together with ChIP assays indicated that CHD7 can bind to the promoters of target genes to maintain chromatin accessibility and facilitate transcription. We found that CHD7 knockdown downregulates AK4 expression and activates AMPK phosphorylation, thereby promoting the phosphorylation and stability of p53 and leading to the inhibition of the colorectal cancer growth. Our genomic analyses of ATPCRs across large-scale cancer specimens identified potential therapeutic targets and our experimental studies revealed a novel CHD7-AK4-AMPK-p53 axis that plays an oncogenic role in colorectal cancer.
Project description:The clinical management of colorectal cancer patients has significantly improved due to the identification of new chemotherapeutic targets. Since rapid tumor proliferation is associated with poor patient prognosis, here we characterize the transcriptional signature of rapidly proliferating colorectal cancer cells in an attempt to identify novel candidate therapeutic targets. Therefore, the doubling time of 52 colorectal cancer cell lines was determined and genome-wide expression profiling of a subset of 31 of these cell lines was assessed by microarray analysis.
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:p21-activated kinases (Paks) play an important role in oncogenic signaling pathways, and have therefore been considered as potential therapeutic targets in various cancers. Most studies of Pak function employ loss of function methods such as gene knock-out or knock-down, but these approaches result in loss of both the enzymatic and scaffolding properties of these proteins, and thus may not reflect the effects of small molecule inhibitors that block catalytic function. In this study we use a new transgenic mouse model in which a specific peptide inhibitor of Group I Paks (Pak1, -2, and -3) is conditionally expressed in response to Cre recombinase. Using this model, we show that inhibition of endogenous Pak function impedes the transition of adenoma to carcinoma in an Apc-driven mouse model of colorectal cancer. These effects are mediated by inhibition of Wnt signaling through reduced β-catenin activity as well as suppression of an epithelial-mesenchymal transition program mediated by miR-200 and Snai1. These results highlight the potential therapeutic role of Pak1 inhibitors in colorectal cancer and suggest new therapeutic strategies in this disease.
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:Colorectal cancer (CRC) with high rate of mortality is one of the most commonly diagnosed cancers in worldwide. Advanced colorectal cancer is often accompanied by malignant proliferation of tumor cells. Further researches on colorectal cancer proliferation to find new targets and develop new therapeutic regimen are an important direction for colorectal cancer treatment. In this study, genome-wide RNAi screening was used to discover the essential genes associated with colorectal cancer cell proliferation. We found DKC1 (dyskerin pseudouridine synthase 1) promoted CRC proliferation through binding and modifying ribosomal proteins (RPL10A, RPL22L1, RPL34, RPS3) mRNA to increase the mRNAs stability and eventually increasing their expression. Besides, DKC1 is highly expressed in colorectal cancer and its aberrantly high expression is associated with poor prognosis of colorectal cancer patients. These results suggest that DKC1 could be a new therapeutic target for colorectal cancer.
Project description:The mitochondrial enzyme ALDH1B1 is upregulated in colorectal and pancreatic adenocarcinomas and promotes tumor growth. Using both genetic and chemical perturbations, we have characterized the ALDH1B1-regulated transcriptome in a colorectal cancer cell line. Genes induced by ALDH1B1 include those related to mitochondrial metabolism, stemness, and ribosomal function. These findings implicate ALDH1B1 in cancer metabolism and cancer stem cell maintenance, and they underscore the potential of ALDH1B1 as a therapeutic target.
Project description:Cancer-associated fibroblasts (CAFs), the principal components of tumor microenvironment, play multiple roles in breast cancer onset and progression. While their impact is widely accepted, treatment options to target CAFs in clinical practice were not yet well established. The nuclear receptor superfamily encompasses a druggable class of molecules, expressed in various stroma and parenchymal cell types, with the interesting therapeutic potential to modulate the reactive microenvironment. Having already addressed the oncosuppressive role of the nuclear Farnesoid X Receptor (FXR) in mammary epithelial cancer cells, the present study is aimed to assess the function of FXR in CAFs and evaluate whether its activation may affect their tumor-promoting features.