Expression data comparing KRas(G12D/+);CreT, R26(H1047R/+);KRas(G12D/+);CreT, and MMTV-Neu mouse mammary tumors
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ABSTRACT: 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:Oncogenic STAT3 functions are known in various malignancies. We found that STAT3 plays an unexpected tumor suppressive role in KRAS-mutant non-small-cell-lung cancer (NSCLC). In mice, tissue-specific inactivation of Stat3 resulted in increased Kras (G12D)-driven NSCLC initiation and malignant progression leading to markedly reduced survival. Clinically, low STAT3 expression levels correlate with poor survival in human lung adenocarcinoma patients with smoking history. Consistently, KRAS-mutant lung tumors showed reduced STAT3 levels. Mechanistically, we show that STAT3 controls NFκB-induced IL-8-expression by sequestering NFκB in the cytoplasm while IL-8 in turn regulates myeloid tumor infiltration and tumor vascularization thereby promoting tumor progression. These results identify a novel STAT3-NFκB-IL-8 axis in KRAS-mutant NSCLC with therapeutic and prognostic relevance WT: Control lung; KRAS: Lung tumors expressing KRAS G12D; KRAS STAT3 KO: Lung tumors expressing KRAS G12D- STAT3 deficient; tumors of four mice pooled per sample
Project description:Mice bearing a G12D activating mutation in Kras consistently develop lung adenocarcinomas in a manner analogous to humans. By performing small and large RNA sequencing on KrasG12D tumors from F1 hybrid mice we were able to identify genes and microRNAs differentially expressed in these tumor samples. Quantification of reads that cover single nucleotide polymorphisms that distinguish between the parental mouse strains enabled an analysis of allele specific expression and imprinting status in these tumors. mRNA and small RNA fractions of mouse lungs and lung adenocarcinomas were deep sequenced in triplicate
Project description:To assess the transcriptional profile within tumours AhcreERTR26flEYFP/wt LSL Kras+/G12D animals were treated with diethylnitrosamine for 8 weeks prior to induction of the Kras allele with a single dose of β-naphthoflavone (20 mg/kg) and tamoxifen (0.25 mg). Subsequently, animals were treated with Sorafenib for 6 weeks. Gene expression array analysis was performed on 12 squamous cell carcinomas (SCCs) from 4 animals.
Project description:We wished to investigate the role of E-cadherin loss in our mouse parietal cell/pre-parietal cell E-cadherin knock-out, p53 knock-out, oncogenic Kras induced model of gastric cancer. As such, we isolated RNA from stomach tissue from our E-cadherin knock-out model (Atp4b-Cre;Cdh1(fl/fl);Kras(LSL-G12D/+);Trp53(fl/fl);Rosa26(LSL-YFP/LSL-YFP)) and our E-cadherin heterozygous model (Atp4b-Cre;Cdh1(fl/+);Kras(LSL-G12D/+);Trp53(fl/fl);Rosa26(LSL-YFP/LSL-YFP)). We then performed a microarray on this stomach tissue from four independent mice of each genotype. Differentially expressed genes were identified and gene set overlap analysis was used to identify pathways enriched in one model over the other.
Project description:The design of potent RAS inhibitors benefits from a molecular understanding of the dynamics in KRAS and NRAS and their oncogenic mutants. Here we characterize switch-1 dynamics in GTP-state KRAS and NRAS by 31P NMR, by 15N relaxation dispersion NMR, hydrogen-deuterium exchange mass spectrometry (HDX-MS), and molecular dynamics simulations. In GMPPNP-bound KRAS and NRAS, we see the co-existence of two conformational states, corresponding to an “inactive” state-1 and an “active” state-2, as previously reported. The KRAS oncogenic mutations G12D, G12C and G12V only slightly affect this equilibrium towards the “inactive” state-1, with rank order wt < G12C < G12D < G12V. In contrast, the NRAS Q61R oncogenic mutation shifts the equilibrium fully towards the “active” state-2. Our molecular dynamics simulations explain this by the observation of a transient hydrogen bond between the Arg61 side chain and the Thr35 backbone carbonyl oxygen. NMR relaxation dispersion experiments with GTP-bound KRAS Q61R confirm a drastic decrease in the population of state-1, but still detect a small residual population (1.8%) of this conformer. HDX-MS indicates that higher populations of state-1 correspond to increased hydrogen-deuterium exchange rates in some regions and increased flexibility, whereas low state-1 populations are associated with KRAS rigidification. We elucidated the mechanism of action of a potent KRAS G12D inhibitor, MRTX1133. Binding of this inhibitor to the switch-2 pocket causes a complete shift of KRAS G12D towards the “inactive” conformation and prevents binding of effector RAS-binding domain (RBD), by signaling through an allosteric network.
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:WAP-Cre:Ptenf/f:p53lox.stop.lox_R270H composite mice were generated by genetic crossing. In these mice, Pten is deleted and a R270H p53 mutation in the DNA binding domain is induced upon expression of Cre recombinase in pregnancy-identified alveolar progenitors. Tumors were characterized by histology, marker analysis, various bioinformatics methods, high-throughput (HTP) FDA-drug screen as well as orthotopic injection to quantify tumor initiating cells (TICs) and tail-vein injection to identify lung-metastasis. Expression data comparing 2 types of Pten-deficient tumors (spindle and poorly differentiated) with other modles of mouse mammary tumors 2 types of Pten deletion plus p53-R270H mutation tumors (spindle and poorly differentiated) was compared with MMTV-Neu, Spindle Pten-p53-deficient tumors, and wild-type mammary gland cells.
Project description:To model the effect of Pten loss on breast cancer, we deleted Pten using a floxed allele and the deleter lines MMTV-Cre(NLST), which targets stem/bi-potent progenitor cells, and WAP-Cre, which targets CD24-positive, pregnancy-identified stem cells/alveolar progenitors. Mammary tumors were detected in WAP-Cre:Ptenf/f females with a latency of 15.2 months. By 18 months, nearly all mice had succumbed to cancer. MMTV-Cre:Ptenf/f mice developed mammary tumors after a longer latency of 26.4 months and reduced penetrance (70%) compared to WAP-Cre:Ptenf/f mice. Tumors from both models were heterogeneous, consisting primarily of differentiated adenocarcinoma (adenomyoepithelioma; ~70%) and adenosquamous carcinoma (20-25%). In addition, a small fraction of tumors was classified as acinar and poorly differentiated adenocarcinoma (4-7%) and adenosarcoma (3-4%). To test the consequences of combined Pten and p53 gene mutation on breast cancer, we deleted both genes via MMTV-Cre or WAP-Cre. Kaplan-Meier tumor free survival curves revealed that WAP-Cre:Ptenf/f:p53f/f and MMTV-Cre:Ptenf/f:p53f/f females developed tumors with reduced latency of 11.3 and 9.8 months, compared with 15.2, 26.4, and 16.9 months for single-mutant WAP-Cre:Ptenf/f, MMTV-Cre:Ptenf/f or MMTV-Cre:p53f/f mice, respectively. In contrast to the heterogeneity of Pten tumors and small percentage of adenosarcomas in these mice, ~70% of Pten:p53 lesions were histologically classified as adeno-sacrcomatoid-like or mesenchymal-like breast cancer, with the rest exhibiting mixed mesenchymal plus adenocarcinomas and differentiated adenocarcinomas. The adeno-sacrcomatoid-like tumors expressed the mesenchymal markers vimentin, K5, SMA, N-cadherin and desmin but not ER, as well as islands of luminal-like K18 expressing cells surrounded by a layer of K14-positive cells. We used microarrays to detect differentially expressed genes in the Pten:p53 double-knock-out vs Pten or p53 single deletions Total RNA was extracted from tumors developed by double Trizol method and hybridized on Affymetrix microarrays.
Project description:To investigate the impact of combined Rb and p53 loss in mammary tumorigenesis, we used transgenic and viral approaches to delete Rb and p53 floxed alleles specifically in the mouse mammary epithelium. Although MMTV-Cre (NLST) targets stem/bi-potent progenitors in the mammary gland, a subset of MMTV-Cre:Rbf/f;p53f/f mice developed non-mammary tumors. Thus, freshly isolated primary mammary epithelial cells from these animals were transplanted into the mammary fat pads of immunodeficient mice and monitored for tumor formation. In addition, primary MECs were isolated from Cre-negative Rbf/f;p53f/f mice, infected with Ad-Cre followed by orthotopic transplantation. In all these cases, resulting tumors shared similar spindle-shape histology, expressed high levels of vimentin, a mesenchymal marker, but not E-cadherin, a luminal marker, and were classified as adeno-sacrcomatoid/spindle-cell/mesenchymal-like breast cancer. We used microarrays to detect differentially expressed genes in the Rb/p53 double-knock-out vs p53 single deletion or normal mammary tissue. Total RNA was extracted from tumors developed by double Trizol method and hybridized on Affymetrix microarrays
Project description:Description: (Supplemental data for Project PXD035399) “Analysis of context-specific KRAS-effectors (sub)complexes in Caco-2 cells”. Proteome of Caco-2 cells, transfected with KRAS-G12D and stimulated with different conditions.