Project description:Based on the previous eVIP study (Cancer Cell, 2016), we profiled the transcriptomes of lung adenocarcinoma cell lines expressing oncogenic KRAS and TP53 to compare methods and investigate the effects of these oncogenes on the cells' whole transcriptomes.
Project description:Aberrant activation of RAS oncogenes is a prevalent event in lung adenocarcinoma, with somatic mutation of KRAS occurring in ~30% of tumors. Recently, we identified somatic mutation of the RAS-family GTPase RIT1 in lung adenocarcinoma, but relatively little is known about the biological pathways regulated by RIT1 and how these relate to the oncogenic KRAS network. Here we present (quantitative proteomic and) transcriptomic profiles from KRAS-mutant and RIT1-mutant isogenic lung epithelial cells and globally characterize the signaling networks regulated by each oncogene.
Project description:While mutations in the KRAS oncogene are amongst the most prevalent in human cancer, there are few successful treatments to target these tumors. It is also likely that heterogeneity in KRAS-mutant tumor biology significantly contributes to the response to therapy. We hypothesized that presence of commonly co-occurring mutations in STK11 and TP53 tumor suppressors may represent a significant source of heterogeneity in KRAS-mutant tumors. To address this, we utilized a large cohort of resected tumors from 442 lung adenocarcinoma patients with data including annotation of prevalent driver mutations (KRAS, EGFR) and tumor suppressor mutations (STK11 and TP53), microarray-based gene expression and clinical covariates including overall survival (OS). Specifically, we determined impact of STK11 and TP53 mutations on a new KRAS mutation-associated gene expression signature as well as previously defined signatures of tumor cell proliferation and immune surveillance responses. Interestingly, STK11, but not TP53 mutations, were associated with highly elevated expression of KRAS mutation-associated genes. Mutations in TP53 and STK11 also impacted tumor biology regardless of KRAS status, with TP53 strongly associated with enhanced proliferation and STK11 with suppression of immune surveillance. These findings illustrate the remarkably distinct ways through which tumor suppressor mutations may contribute to heterogeneity in KRAS-mutant tumor biology. In addition, these studies point to novel associations between gene mutations and immune surveillance that could impact the response to immunotherapy.
Project description:Lo A, Holmes K, Mundt F, Moorthi S, Fung I, Fereshetian S, Watson J, Carr SA, Mertins P, Berger A. Aberrant activation of RAS oncogenes is a prevalent event in lung adenocarcinoma, with somatic mutation of KRAS occurring in ~30% of tumors. Recently, we identified somatic mutation of the RAS-family GTPase RIT1 in lung adenocarcinoma, but relatively little is known about the biological pathways regulated by RIT1 and how these relate to the oncogenic KRAS network. Here we present quantitative proteomic and transcriptomic profiles from KRAS-mutant and RIT1-mutant isogenic lung epithelial cells and globally characterize the signaling networks regulated by each oncogene. We find that both mutant KRAS and mutant RIT1 promote S6 kinase, AKT, and RAF/MEK signaling, and promote epithelial-to-mesenchymal transition and immune evasion via HLA protein loss. However, KRAS and RIT1 diverge in regulation of phosphoproteins including EGFR, USO1, and AHNAK proteins. The majority of the proteome changes are related to altered transcriptional regulation, but a small subset of proteins are differentially regulated at the post-transcriptional level, including intermediate filament proteins, metallothioneins, and MHC Class I proteins, which are profoundly suppressed by oncogenic KRAS and RIT1 variants. These data provide the first global, unbiased characterization of oncogenic RIT1 network and identify the shared and divergent functions of oncogenic RIT1 and KRAS GTPases in lung cancer.
Project description:The proto-oncogene KRAS is mutated in a wide array of human cancers, most of which are aggressive and respond poorly to standard therapies. Although the identification of specific oncogenes has led to the development of clinically effective, molecularly targeted therapies in some cases, KRAS has remained refractory to this approach. An alternative strategy for targeting KRAS is to identify gene products that, when suppressed or inhibited, result in cell death only in the presence of an oncogenic allele. Here we have used systematic RNA interference (RNAi) to detect synthetic lethal partners of oncogenic KRAS and found that the non-canonical IkB kinase, TBK1, was selectively essential in cells that harbor mutant KRAS. Suppression of TBK1 induced apoptosis specifically in human cancer cell lines that depend on oncogenic KRAS expression. In these cells, TBK1 activated NF- B anti-apoptotic signals involving cREL and BCL-XL that were essential for survival, providing mechanistic insights into this synthetic lethal interaction. These observations identify TBK1 as a potential therapeutic target in KRAS mutant tumors and establish a general approach for the rational identification of co-dependent pathways in cancer. This SuperSeries is composed of the following subset Series:; GSE17643: Profiling of immortalized human lung epithelial cells following oncogenic KRAS expression and TBK1 suppression; GSE17671: Profiling of immortalized human lung epithelial cells following infection with oncogenic KRAS (G12V) Experiment Overall Design: Refer to individual Series
Project description:To reveal the impact of mutant KRAS on the proteome of Pancreatic Ductal Adenocarcinoma (PDAC) cells, we carried out a quantitative phospho-proteomic analysis of tumour cells isolated from an inducible mouse model of PDAC (iKras PDAC) (Ying et al., 2012). In this model, oncogenic Kras (G12D) expression can be controlled by administration of doxycycline (Dox). A timecourse Dox removal experiment was carried out in which cells with or without Dox removal at 12, 24, 36, and 48 hrs intervals were lysed and analysed by quantitative proteomics using Tandem Mass Tagging (TMT). Two independent biological replicate experiments were carried out, with timecourse samples in each replicate being barcoded and pooled together using TMT 10plex labelling kit (Thermo).
Project description:Oncogenic mutations in tumor cells regulate signaling both within tumor cells and heterotypic stromal cells. However, whether oncogenes regulate tumor cell signaling via stromal cells is poorly understood. Here we show that oncogenic KRAS (KRAS-G12D) uniquely regulates tumor cell signaling via stromal cells. By combining cell-specific proteome labeling with phosphoproteomic multiplexing we conducted a multivariate analysis of heterocellular KRAS-G12D signaling in Pancreatic Ductal Adenocarcinoma (PDA) cells. By engaging heterotypic fibroblasts, KRAS-G12D drives unique reciprocal signaling in tumor cells to employ additional kinases and double the number of regulated signaling nodes from cell-autonomous KRAS-G12D. Heterocellular signaling produces a distinct tumor cell phosphoproteome, total proteome, and increase mitochondria capacity via an IGF1R/AXL-AKT axis. Reciprocal KRAS-G12D phenotypes require a heterocellular context and are unreachable by cell-autonomous KRAS-G12D alone. These results demonstrate oncogene signaling should be viewed as a heterocellular process and our existing homocellular perspective underrepresents the extent of oncogene signaling in cancer.
Project description:To reveal the impact of mutant KRAS expression on the proteome of Pancreatic Ductal Adenocarcinoma (PDAC) cells, we carried out a timecourse quantitative proteomic analysis of tumour cells isolated from an inducible mouse model of PDAC (iKras PDAC) (Ying et al., 2012). In this model, oncogenic Kras (G12D) expression can be controlled by administration of doxycycline(Dox). Cells were grown in the absence of Dox for 48 hrs, before being treated with or without Dox for 4, 8, 12, 24, and 36 hrs, followed by total lysis and quantitative proteomics analysis using Tandem Mass Tagging (TMT). A total of 2 biological replicate experiments were analysed, with all samples from each replicate barcoded and pooled together using TMT 10plex labelling kit (Thermo).