Chromosomal and microsatellite instability in colorectal cancer (Homo sapiens)
From WikiPathways
Description
This pathway is based on information from KEGG
The most common mutation in colon cancer is inactivation of APC. When APC does not have an inactivating mutation, frequently there are activating mutations in β-catenin. In order for cancer to develop, both alleles must be mutated. Mutations in APC or β-catenin must be followed by other mutations to become cancerous; however, in carriers of an APC inactivating mutations, the risk of colorectal cancer by age 40 is almost 100%.
The impact of KRAS mutations is heavily dependent on the order of mutations. Primary KRAS mutations generally lead to a self-limiting hyperplastic or borderline lesion, but if they occur after a previous APC mutation it often progresses to cancer. KRAS mutation is predictive of a very poor response to panitumumab and cetuximab therapy in colorectal cancer. Currently, the most reliable way to predict whether a colorectal cancer patient will respond to one of the EGFR-inhibiting drugs is to test for certain “activating” mutations in the gene that encodes KRAS, which occurs in 30%–50% of colorectal cancers. Studies show patients whose tumors express the mutated version of the KRAS gene will not respond to cetuximab or panitumumab. Source: Wikipedia
DCC can be considered a conditional tumor suppressor gene as well as a conditional oncogene. When DCC is present and not activated by netrin it is proapoptotic, and represses tumor formation. When DCC is present and netrin-activated it promotes cell survival, acting as an oncoprotein. One of the most frequent genetic abnormalities that occur in advanced colorectal cancer is loss of heterozygosity (LOH) of DCC in region 18q21. Source: Wikipedia
de Miranda et al suggest that TGFβ signaling remains active in some CRC cells with MSI mutations in the TGFBR2 gene, because the mutated gene still expresses a functional protein.
Aberrant overexpression of cyclooxygenase-2 (COX-2) is thought to have an important role in development of CRC. The tumorigenic effects of COX-2 can be attributed to the production of PGE2; increased levels of PGE2 have been reported in colorectal adenomas as well as carcinomas. COX-2 and PGE2 regulate proliferation, survival, migration, and invasion in colorectal tumors. Source: Pino et al. Phosphorylation sites were added based on information from PhosphoSitePlus (R), www.phosphosite.org.
Proteins on this pathway have targeted assays available via the CPTAC Assay PortalQuality Tags
Ontology Terms
Bibliography
View all... |
- Miyaki M, Kuroki T; ''Role of Smad4 (DPC4) inactivation in human cancer.''; Biochem Biophys Res Commun, 2003 PubMed Europe PMC Scholia
- Pino MS, Chung DC; ''The chromosomal instability pathway in colon cancer.''; Gastroenterology, 2010 PubMed Europe PMC Scholia
- de Miranda NF, van Dinther M, van den Akker BE, van Wezel T, ten Dijke P, Morreau H; ''Transforming Growth Factor β Signaling in Colorectal Cancer Cells With Microsatellite Instability Despite Biallelic Mutations in TGFBR2.''; Gastroenterology, 2015 PubMed Europe PMC Scholia
- Hornbeck PV, Zhang B, Murray B, Kornhauser JM, Latham V, Skrzypek E; ''PhosphoSitePlus, 2014: mutations, PTMs and recalibrations.''; Nucleic Acids Res, 2015 PubMed Europe PMC Scholia
- Takagi Y, Kohmura H, Futamura M, Kida H, Tanemura H, Shimokawa K, Saji S; ''Somatic alterations of the DPC4 gene in human colorectal cancers in vivo.''; Gastroenterology, 1996 PubMed Europe PMC Scholia
- De Bosscher K, Hill CS, Nicolás FJ; ''Molecular and functional consequences of Smad4 C-terminal missense mutations in colorectal tumour cells.''; Biochem J, 2004 PubMed Europe PMC Scholia
- Amado RG, Wolf M, Peeters M, Van Cutsem E, Siena S, Freeman DJ, Juan T, Sikorski R, Suggs S, Radinsky R, Patterson SD, Chang DD; ''Wild-type KRAS is required for panitumumab efficacy in patients with metastatic colorectal cancer.''; J Clin Oncol, 2008 PubMed Europe PMC Scholia
- Koyama M, Ito M, Nagai H, Emi M, Moriyama Y; ''Inactivation of both alleles of the DPC4/SMAD4 gene in advanced colorectal cancers: identification of seven novel somatic mutations in tumors from Japanese patients.''; Mutat Res, 1999 PubMed Europe PMC Scholia
- Amado RG, Wolf M, Peeters M, Van Cutsem E, Siena S, Freeman DJ, Juan T, Sikorski R, Suggs S, Radinsky R, Patterson SD, Chang DD; ''Wild-type KRAS is required for panitumumab efficacy in patients with metastatic colorectal cancer.''; J Clin Oncol, 2008 PubMed Europe PMC Scholia
- Neumann J, Zeindl-Eberhart E, Kirchner T, Jung A; ''Frequency and type of KRAS mutations in routine diagnostic analysis of metastatic colorectal cancer.''; Pathol Res Pract, 2009 PubMed Europe PMC Scholia
- Mazzoni SM, Fearon ER; ''AXIN1 and AXIN2 variants in gastrointestinal cancers.''; Cancer Lett, 2014 PubMed Europe PMC Scholia
- Neumann J, Zeindl-Eberhart E, Kirchner T, Jung A; ''Frequency and type of KRAS mutations in routine diagnostic analysis of metastatic colorectal cancer.''; Pathol Res Pract, 2009 PubMed Europe PMC Scholia
History
View all... |
External references
DataNodes
View all... |
Annotated Interactions
No annotated interactions