Project description:To investigate the effect of activating GNAS mutation on gene expression of colorectal cancer cells, we utilized the GNAS R201C knockin cell line produced by Horizon Discovery Ltd. We compared the gene expression of parental and GNAS R201C/+ HCT116 cells with RNA-Seq, using four biological replicates.
Project description:Analysis of skin lesions from adult mice with epidermal conditional deletion of heterotrimeric G protein Galpha s in cytokeratin 14 positive cells, compared with control mouse skin. Epidermal Gnas ablation leads to skin defects, including basal cell carcinoma (BCC). Results provide insight into role of Galpha s in the regulation of stem cells from the skin. Changes in gene expression following Gnas deletion from the mouse epidermis were analyzed. Skin from four independent mice of each wild type (control) and Gnas epidermal knockout (Gnas eKO) were analyzed.
Project description:To investigate the function of ID4 in colon cancer cells, we collected total RNA from both HCT116-SC and HCT116-shID4 and examined mRNA expression profile, comprehensively.
Project description:GNAS, a gene encoding G-protein stimulating alpha subunit, is frequently mutated in intraductal papillary mucinous neoplasms (IPMNs), which is an indolent and slow-growing pancreatic neoplasm that secretes abundant mucin. GNAS mutation is not observed in conventional ductal adenocarcinomas of the pancreas. To determine the functional significance of GNAS mutation in pancreatic ductal cells, we examined in vitro phenotypes and gene expression profiles of cells of pancreatic ductal lineage, HPDE, PK-8, PCI-35, and MIA PaCa-2, with exogenous expression of either wild-type or mutated (R201H) GNAS. We found that exogenous GNAS upregulated intracellular cyclic-adenine monophosphate, particularly in the mutated GNAS transfectants. Exogenous GNAS induced no obvious cell-growth promotion, but induced suppression in some cells. The exogenous GNAS upregulated MUC2 and MUC5AC in HPDE and PK-8, and the latter was most sensitive to exogenous GNAS, exhibiting drastic alteration of the global gene expression that is consistent with that of IPMN. Hence, PK-8 expressing exogenous mutated GNAS may be an ideal in vitro model of IPMN. On the other hand, exogenous GNAS downregulated expression of mucin genes and produced modest alteration of gene expression profiles in PCI-35 and MIA PaCa-2, indicating lower sensitivity to exogenous GNAS. Furthermore, we showed diverse and cell-type specific mucin expression pathways with complicated interactions between signaling pathways of the G-protein coupled receptor (GPCR), the mitogen-activated protein kinase (MAPK), and the phosphatidylinositol 3 kinase (PI3K), in which the GPCR pathway appeared to be dominant in some and the MAPK pathway in others. In conclusion, mutated GNAS found in IPMNs may extensively alter gene expression profiles, including expression of mucin genes, with the interaction with MAPK and PI3K pathways in pancreatic ductal-lineage cells, which may determine the characteristic phenotype of the neoplasm. Cells of pancreatic cancer cell lines, PK-8, PCI-35,and MIA PaCa-2, were seeded at 4 M-CM-^W 10^5 cells/well in 6-well plates and incubated for 24 hours at 37M-BM-0C in 5% CO2 with humid atmosphere. Then the cells were transfected with either pcDNA 3.1/V5-His vector or pcDNA3.1-GNAS(R201H)-V5-His vector using Lipofectamine 2000 reagent (Life Technologies) according to the manufacturerM-bM-^@M-^Ys recommendations. The cells were incubated for 24 hours and collected by dissociation using trypsin. Total RNAs were isolated using the RNeasy Mini kit (Qiagen, Hilden, Germany). Serial analysis of gene expression (SAGE) library was constructed using a SOLiD SAGE Kit (Life Technologies) according to the manufactureM-bM-^@M-^Ys instruction. The constructed libraries were analysed by means of the massively parallel sequencing method using SOLiD 4 System (Life Technologies). The SAGE analysis was performed for samples obtained from single transfection experiment.
Project description:RNA-seq was performed on parental HCT116 colon cancer cell line and on HCT116 DKO (double knock-out) cell line, which contains genetic knockouts of both DNA methyltransferases DNMT1 (-/-) and DNMT3b (-/-).
Project description:We investigated the effect of GNAS(R201C) expression in the Kras;Gnas model of pancreatic intraductal papillary mucinous neoplasms where transgenic mutant GNAS is doxycycline inducible (LGKC; p48(Cre), Kras(LSL-G12D), Rosa26(LSL-rtTA)), Tg(TetO-GNAS(R201C)) using scRNA-seq of dissociated pancreatic tissues.
Project description:We analyzed the molecular mechanism of regulation of EPHX2 on colon cancer by constructing colon cancer cell line HCT116 stably transfected with EPHX2.
Project description:GNAS, a gene encoding G-protein stimulating alpha subunit, is frequently mutated in intraductal papillary mucinous neoplasms (IPMNs), which is an indolent and slow-growing pancreatic neoplasm that secretes abundant mucin. GNAS mutation is not observed in conventional ductal adenocarcinomas of the pancreas. To determine the functional significance of GNAS mutation in pancreatic ductal cells, we examined in vitro phenotypes and gene expression profiles of cells of pancreatic ductal lineage, HPDE, PK-8, PCI-35, and MIA PaCa-2, with exogenous expression of either wild-type or mutated (R201H) GNAS. We found that exogenous GNAS upregulated intracellular cyclic-adenine monophosphate, particularly in the mutated GNAS transfectants. Exogenous GNAS induced no obvious cell-growth promotion, but induced suppression in some cells. The exogenous GNAS upregulated MUC2 and MUC5AC in HPDE and PK-8, and the latter was most sensitive to exogenous GNAS, exhibiting drastic alteration of the global gene expression that is consistent with that of IPMN. Hence, PK-8 expressing exogenous mutated GNAS may be an ideal in vitro model of IPMN. On the other hand, exogenous GNAS downregulated expression of mucin genes and produced modest alteration of gene expression profiles in PCI-35 and MIA PaCa-2, indicating lower sensitivity to exogenous GNAS. Furthermore, we showed diverse and cell-type specific mucin expression pathways with complicated interactions between signaling pathways of the G-protein coupled receptor (GPCR), the mitogen-activated protein kinase (MAPK), and the phosphatidylinositol 3 kinase (PI3K), in which the GPCR pathway appeared to be dominant in some and the MAPK pathway in others. In conclusion, mutated GNAS found in IPMNs may extensively alter gene expression profiles, including expression of mucin genes, with the interaction with MAPK and PI3K pathways in pancreatic ductal-lineage cells, which may determine the characteristic phenotype of the neoplasm.
Project description:The GNASR201 gain-of-function mutation is the single most frequent cancer-causing mutation across all heterotrimeric G proteins, driving oncogenesis in various low-grade/benign gastrointestinal and pancreatic tumors. In this study, we investigated the role of GNAS and its product Gαs in tumor progression using peritoneal models of colorectal cancer (CRC). GNAS was knocked out in multiple CRC cell lines harboring GNASR201C/H mutations (KM12, SNU175, SKCO1), leading to decreased cell-growth in 2D and 3D organoid models. Nude mice were peritoneally injected with GNAS-knockout KM12 cells, leading to a decrease in tumor growth and drastically improved survival at 7 weeks. Supporting these findings, GNAS overexpression in LS174T cells led to increased cell-growth in 2D and 3D organoid models, and increased tumor growth in PDX mouse models. GNAS knockout decreased levels of cyclic AMP in KM12 cells, and molecular profiling identified phosphorylation of β-catenin and activation of its targets as critical downstream effects of mutant GNAS signaling. Supporting these findings, chemical inhibition of both PKA and β-catenin reduced growth of GNAS mutant organoids. Our findings demonstrate oncogene addiction to GNAS in peritoneal models of GNASR201C/H tumors, which signal through the cAMP/PKA and Wnt/β-catenin pathways. Thus, GNAS and its downstream mediators are promising therapeutic targets for GNAS mutant tumors.