Project description:The RAS pathway is among the most frequently activated signaling nodes in cancer. However, the mechanisms that alter RAS activity in human pathologies are not yet fully understood. K128 ubiquitination is the most prevalent modification of the GTPase core domain in both NRAS and KRAS. The ubiquitination at K128 was decreased in cancer samples compared to normal tissue. We found that K128 ubiquitination creates an additional binding interface for RAS GTPase-activating proteins (GAP), NF1 and RASA1, which increases RAS binding to GAP proteins and promotes GAP-mediated GTP hydrolysis. K128 ubiquitination is transiently induced by growth factors or cytokines, which restricts the extent of wild-type RAS activation in a GAP-dependent manner. In contrast, the loss of K128 ubiquitination in the KRAS-G12D mutant promotes tumor growth by suppressing RAL/ TBK1 signaling and negatively regulating the autocrine circuit induced by mutant KRAS. Dysregulation of K128 ubiquitination unleashes both wild-type and mutant RAS signaling and triggers a senescence-associated secretory phenotype, driving RAS-driven tumorigenesis.
Project description:The goal of this study was to compare expression profiles of mouse Kras G12D Trp53 -/- lung cancer cells that have inactivated MGA compared to controls
Project description:KRAS is one of the most frequently mutated genes across all cancer subtypes. Two of the most frequent oncogenic KRAS mutations observed in patients result in glycine to aspartic acid substitution at either codon 12 (G12D) or 13 (G13D). Although the biochemical differences between these two predominant mutations are not fully understood, distinct clinical features of the resulting tumors suggest involvement of disparate signaling mechanisms. When we compared the global and phosphotyrosine proteomic profiles of isogenic colorectal cancer cell lines bearing either G12D or G13D KRAS mutation, we observed both shared as well as unique signaling events induced by the two KRAS mutations.
Project description:Transcriptional profiling of Aza+ITF-2357 treated bone marrow derived macrophages vs. Mock treated bone marrow derived macrophages. Aim was to elucidate the effects of epigentic drug treatment on in vitro cultured macrophages and to compare these data to in vivo treated macrophage populations. Transcriptional profiling of NSCLC cell lines treated with epigenetic agents Transcriptional profiling of immune populations in the lung Kras G12D tumor micronevironment treated with combination epigenetic therapy Transcriptional profiling of lung Kras G12D tumors treated with combination epigenetic therapy
Project description:Breast Cancer (BC) has been associated with alterations in signaling through a number of growth factor and hormone regulated pathways. Mouse models for metastatic BC have been developed using oncoproteins that activate PI3K, Stat3 and Ras signaling. To determine the role of each pathway, we analyzed mouse mammary tumor formation when they were activated singly or pairwise. We used microarrays to detect differentially expressed genes in the KRas(G12D/+);CreT and R26(H1047R/+);KRas(G12D/+);CreT tumors Total RNA was extracted from tumors developed by Qiagen RNAeasy kit and hybridized on Affymetrix microarrays.
Project description:Activation of endogenously expressed KRas[G12D] in the pancreas of mice gives rise primarily to early stage PanIN lesions, however such lesions can occasionally progress to end-stage ductal adenocarcinoma (PDAC). Progression of KRas[G12D]- initiated lesions to PDAC is accelerated by modest expression of MYC from the Rosa26 locus. Deletion of 1 copy of endogenous c-Myc or both copies of endogenous Zbtb17 (aka Miz1), slows progression to PDAC and extends healthful survival of Pdx1-Cre;lsl-KRas[G12D];Rosa26-lsl-MYC[DM] (KMC) mice. Tumours were removed from mice with all 4 genotypes and validated by histological examination prior to RNA-SEQ analysis.
Project description:Breast Cancer (BC) has been associated with alterations in signaling through a number of growth factor and hormone regulated pathways. Mouse models for metastatic BC have been developed using oncoproteins that activate PI3K, Stat3 and Ras signaling. To determine the role of each pathway, we analyzed mouse mammary tumor formation when they were activated singly or pairwise. We used microarrays to detect differentially expressed genes in the KRas(G12D/+);CreT and R26(H1047R/+);KRas(G12D/+);CreT tumors
Project description:KRAS is an important oncogene in cancer. Long noncoding RNAs (lncRNAs) have been characterized to be involved in various types of cancer. In this study, we investigated the functions of KRAS-responsive lncRNAs in cancer. We perfomed the RNA-seq to examine the lncRNA expression after overexpession of KRAS WT and G12D in H1299 cells.
Project description:RAS-MAPK activating mutations in NRAS, KRAS and PTPN11 were present in 24/55 (44%) cases in our series of diangosis and relapsed ALL. To evaluate the specific role of RAS-MAPK activating mutations in chemotherapy resistance in ALL we used primary isogenic leukemia cells expressing either Kras wild type or a mutant oncogenic form of Kras (Kras G12D) Mechanistically, functional dissection of Kras wild type and mutant Kras (Kras G12D) isogenic ALL cells demonstrated induction of methotrexate resistance, but also improved response to vincristine, in mutant Kras-expressing ALL cells. These results pave the road for the development of tailored personalized therapies for the treatment of relapsed ALL