Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Epithelial TGFβ activation engages growth-factor signalling to circumvent cell death and drive intestinal tumorigenesis with aggressive features.

ABSTRACT: The pro-tumourigenic role of epithelial TGFβ in colorectal cancer (CRC) has been controversial. Here we identify a cohort of aggressive ‘bad acting’ early-stage (T1) disseminating tumours characterised by high cell-intrinsic TGFβ signalling emanating from the epithelium, not stroma. To address its functional significance, we activated TGFβ signalling in the murine intestinal epithelium either alone or in concert with the common tumour suppressive and oncogenic mutations found in CRC, namely Apc and Kras. Consistent with previous studies, we found that activation of TGFβ rapidly induced apoptosis in Apc-mutant intestine and completely killed Apc-mutant organoids. However, in the presence of both Apc and Kras mutation, activation of TGFβ within the epithelium rampantly accelerates tumourigenesis. Importantly the transcriptional signatures derived from these mice overlapped with the “bad acting” T1 human tumours and this signalling could also predict recurrence in stage II CRC. Mechanistically, the activation of intrinsic TGFβ induced the expression of a growth-factor signalling module containing EGFR that synergised with Apc and Kras to drive marked activation of MAPK signalling. Importantly, inhibition of MEK and/or EGFR suppressed the acceleration conferred by TGFβ even in Kras-mutant cells, which are refractory to MEK/EGFR inhibition in the absence of epithelial TGFβ. Together, we identify both a determinant of early dissemination and a potential vulnerability for tumours with these born-to-be-bad traits.

ORGANISM(S): Mus musculus

PROVIDER: GSE182019 | GEO | 2021/08/13

REPOSITORIES: GEO

ACCESS DATA

Json Xml

Dataset's files

Source:

			Action	DRS
		Other

Items per page:

1 - 1 of 1

Similar Datasets

The amino acid transporter SLC7A5 is required for efficient growth of KRAS-mutant colorectal cancer

Project description:Oncogenic KRAS mutations and inactivation of the APC tumour suppressor co-occur in colorectal cancer (CRC). Despite efforts to target mutant KRAS directly, most therapeutic approaches focus upon downstream pathways, albeit with limited efficacy. Moreover, mutant KRAS alters the basal metabolism of cancer cells, rendering them ‘addicted’ to glutamine supporting proliferation. We show that concomitant mutation of Apc and Kras in the mouse intestinal epithelium profoundly rewires metabolism, increasing glutamine consumption. Furthermore, SLC7A5, a glutamine antiporter, is critical for colorectal tumorigenesis in models of both early and late-stage metastatic disease. Mechanistically, SLC7A5 maintains intracellular amino-acid levels following KRAS activation through transcriptional and metabolic reprogramming. This supports the increased demand for bulk protein synthesis that underpins enhanced proliferation of KRAS-mutant cells. Moreover, targeting protein synthesis, via mTORC1 inhibition, cooperates with Slc7a5 deletion to abrogate growth of established KRAS-mutant tumours. Together, these data suggest SLC7A5 as an attractive target for therapy-resistant KRAS-mutant CRC.

2020-11-11 | GSE160479 | GEO

Gene expression analysis of WT, Apc and ApcKras mouse intestine

2020-11-11 | GSE160478 | GEO

Gene expression data from very early stage lesions (T1) of colorectal cancer

Project description:There are ~1.4 million cases of colorectal cancer (CRC) annually worldwide. Due to recent implementation of bowel cancer screening (BCS), incidence of diagnosis with stage I (T1/2, N0, M0) CRC has increased nearly four-fold; from approximately 12% pre-screening to approximately 42-45%. While survival rates for patients diagnosed with stage I CRC remains above 95%, and identification of patients at this early stage provides the best opportunity to improve in cancer survival rates, recent data has provided quantitative evidence that metastatic seeding can occur from disseminated cells at the very earliest stage of CRC development. The aim of study was to give an insight into aggressive “born-to-be-bad” biology through generation and transcriptional profiling of a novel case-controlled retrospective T1 CRC discovery cohort. We performed transcriptional and histological profiling to identify molecular pathology features of the high-risk metastatic phenotypes, discriminating between relapse and non-relapse T1 lesions and found that a cohort of aggressive early disseminating stage 1 CRC is associated with high cell intrinsic TGFB signalling and not stromal signalling.

2021-11-30 | GSE162667 | GEO

Genomic characterization of intrinsic and acquired resistance to cetuximab in colorectal cancer patients

Project description:Anti-EGFR antibodies are effective in therapies for late-stage colorectal cancer (CRC); however, many tumours are unresponsive or develop resistance. We performed genomic analysis of intrinsic and acquired resistance to anti-EGFR therapy in prospectively collected tumour samples from 25 CRC patients receiving cetuximab (an EGFR inhibitor). Of 25 CRC patients, 13 displayed intrinsic resistance to cetuximab; 12 were intrinsically sensitive. We obtained six re-biopsy samples at acquired resistance from the intrinsically sensitive patients. NCOA4–RET and LMNA–NTRK1 fusions and NRG1 and GNAS amplifications were found in intrinsic-resistant patients. In cetuximab-sensitive patients, we found KRAS K117N and A146T mutations in addition to BRAF V600E, AKT1 E17K, PIK3CA E542K, and FGFR1 or ERBB2 amplifications. The comparison between baseline and acquired-resistant tumours revealed an extreme shift in variant allele frequency of somatic variants, suggesting that cetuximab exposure dramatically selected for rare resistant subclones that were initially undetectable. There was also an increase in epithelial-to-mesenchymal transition at acquired resistance, with a reduction in the immune infiltrate. Furthermore, characterization of an acquired-resistant, patient-derived cell line showed that PI3K/mTOR inhibition could rescue cetuximab resistance. Thus, we uncovered novel genomic alterations that elucidate the mechanisms of sensitivity and resistance to anti-EGFR therapy in metastatic CRC patients.

2019-09-21 | E-MTAB-8340 | biostudies-arrayexpress

Gene expression of adherent and spheroid cells derived from both D-WT and D-MT cells

Project description:Mutant KRAS activates cancer stem cells (CSCs) contributing transformation of colorectal cancer (CRC) cells harboring adenomatous polyposis coli (APC) mutations. The factors mediating activation of CSCs by KRAS mutation were systematically investigated through a microarray analysis of the APC-mutated isogenic DLD-1 CRC cells harboring homogeneous wild-type KRAS (D-WT) or mutant KRAS (D-MT). The objective of the study was to find the factors specifically induced in the spheroids harboring both APC and KRAS mutations.

2019-10-16 | GSE119197 | GEO

Polyclonal interactions overcome fitness barriers in Apc-driven intestinal tumorigenesis

Project description:Loss-of-function mutations in the tumour suppressor APC are an initial step in intestinal tumorigenesis. APC-mutant intestinal stem cells (ISCs) outcompete their wild type neighbours through the secretion of Wnt antagonists, accelerating the fixation and subsequent rapid clonal expansion of mutants. Reports of polyclonal intestinal tumours in patients and mouse models appear at odds with this process. Here we combine multicolour lineage tracing with chemical mutagenesis in mice to show that a large proportion of intestinal tumours have a multiancestral origin. Polyclonal tumours retain a structure comprising subclones with distinct Apc mutations and transcriptional states, driven predominantly by differences in KRAS and MYC signalling. These pathway level changes are accompanied by profound cancer stem cell phenotypic differences. Importantly, these findings are confirmed by introducing an oncogenic Kras mutation that results in predominantly monoclonal tumour formation. Further, polyclonal tumours have accelerated growth dynamics suggesting a link between polyclonality and tumour progression. Together, these findings demonstrate the role of interclonal interactions in promoting tumorigenesis through non-cell autonomous pathways dependent on the differential activation of oncogenic pathways between clones.

2024-08-30 | GSE272850 | GEO

Apc restoration promotes cellular differentiation and reestablishes crypt homeostasis in colorectal cancer

Project description:The Adenomatous Polyposis Coli (APC) tumor suppressor is mutated in the vast majority of human colorectal cancers (CRC) and leads to deregulated Wnt signaling. To determine whether Apc disruption is required for tumor maintenance, we developed a mouse model of CRC whereby Apc can be conditionally suppressed using a doxycycline-regulated shRNA. Apc suppression produces adenomas in both the small intestine and colon that, in the presence of Kras and p53 mutations, can progress to invasive carcinoma. In established tumors, Apc restoration drives rapid and widespread tumor-cell differentiation and sustained regression without relapse. Tumor regression is accompanied by the re-establishment of normal crypt-villus homeostasis, such that once aberrantly proliferating cells reacquire self-renewal and multi-lineage differentiation capability. Our study reveals that CRC cells can revert to functioning normal cells given appropriate signals, and provide compelling in vivo validation of the Wnt pathway as a therapeutic target for treatment of CRC Analysis of RNA isolated from colon polyps that presented in shAPC or shAPC/Kras mice as compared to shRenilla (neutral) mouse colon mucosa

2015-06-18 | E-GEOD-67186 | biostudies-arrayexpress

Expression data from subpopulations of Apc1638N/+ intestinal adeno tumors versus Apc1638N/+ / KRAS v12G intestinal adenocarcinomas tumors

Project description:Constitutive activation of the Wnt pathway leads to adenoma formation, an obligatory step towards intestinal cancer. In view of the established role of Wnt in regulating stemness, we attempted the isolation of cancer stem cells (CSCs) from Apc- and Apc/KRAS-mutant intestinal tumours. Whereas CSCs are present in malignant Apc/KRAS–mutant carcinomas, they appear to be very rare (<10-6) in the benign Apc–mutant adenomas. In contrast, the Lin-CD24hiCD29+ subpopulation of adenocarcinoma cells appear to be enriched in CSCs with increased levels of active -catenin. Expression profiling analysis of the CSC-enriched subpopulation confirmed their enhanced Wnt activity and revealed additional differential expression of other signalling pathways, growth factor binding proteins, and extracellular matrix components. As expected, genes characteristic of the Paneth cell lineage (e.g. defensins) are co-expressed together with stem cell genes (e.g. Lgr5) within the CSC-enriched subpopulation. This is of interest as it may indicate a cancer stem cell niche role for tumor-derived Paneth-like cells, similar to their role in supporting Lgr5+ stem cells in the normal intestinal crypt. Overall, our results indicate that oncogenic KRAS activation in Apc-driven tumours results in the expansion of the CSCs compartment by increasing b-catenin intracellular stabilization.

2013-10-01 | GSE47772 | GEO

GEMM CRC collection analysis

Project description:A collection of genetically engineered mouse models (GEMM) of colorectal cancer (CRC) were created, and primary tumors from these GEMMs were analyzed. Primary CRC tumors from these GEMMs were genotyped to confirm that they contain the core genetic lesions of interest, including APC, P53, KRAS, and BRAF. Primary tumors from GEMMs with combinations of lesions of interest were analyzed by whole genome expression, and their expression profiles were compared to determine how they segregate. Signatures were then generated from GEMM tumors of interest and compared to human clinical datasets with expression and outcome data. Primary tumors from CRC GEMMs with different combinations of mutant alleles of interested were generated and analyzed. Alleles include mutant forms of APC (A), P53 (P), KRAS (K) and BRAF (B).

2014-07-01 | E-GEOD-50794 | biostudies-arrayexpress

Transcriptional profiling of intestinal changes in Apc Kras tumours with MYC activation and/or drug combination treatment

Project description:Transcriptional profiling of intestinal changes in Apc Kras tumours with MYC activation and/or drug combination treatment

2021-01-01 | GSE159432 | GEO