KRAS gene

None KRAS gene (mutant allele) Cell culture (Endogenous gene) Cancer (12)... 

Real-time PCR-based detection methods are also frequently used in clinical molecular laboratories. They may be even more preferable because they are fast and run in a closed PCR system, which reduces the risk of contamination. To detect mutations, two probes complementary to wild-type sequences are designed so that one of the probes spans the known mutation site, such as codons 12 and 13 in the KRAS gene. If no mutation... 

COLORECTAL ADENOCARCINOMA EGFR is a tyrosiue kinase receptor. Humanized monoclonal antibody chemotherapy to EGFR blocks its functional activation. Immuno-histochemical documentation of EGFR reactivity within colorectal cancers was once necessary to initiate anti-EGFR therapy. Currently, the initiation of therapy relies on documentation of a normal (wild-type) KRAS gene... 

In patients with metastatic colorectal cancer, the success of anti-EGFR therapy with cetuximab depends on the nonmutated KRAS status. In patients with mutant KRAS, the intracellular signaling continues despite EGFR therapy. Mutated KRAS genes have been detected in about 40% of metastatic colorectal cancer patients. A retrospective analysis of tumor types revealed that patients with wild-type KRAS respond to cetuximab in combination with leucovorin, fluoruracil, and irinotecan (FOLFIRI) with an increase in progression-free survival from 25% without cetuximab to 43% (Van CuTSEM et al. 2008). These results also describe a further step to individualized and customized treatment of cancer with targeted therapies. 

The mechanism by which tamoxifen induces endometrial neoplasms is not known. Possible associations with the MSI, PTEN, beta-catenin, and KRAS genes have been sought in 18 cases of endometrial carcinoma after the use of tamoxifen... 

Rzhetsky A, lossifov I, Koike T, Krauthammer M, Kra P, Morris M, et al. Gene-Ways a system for extracting, analyzing, visualizing, and integrating molecular pathway data. J Biomed Inform 2004 37 43-53. 

PCR primers, product size, and reaction conditions for amplification and direct sequencing of KRAS, BRAF, EGFR, PDGFRa, and CKIT genes... 

Web databases used for comparing sequence variants obtained by mutational analysis CKit, PDGRFA, KRAS, BRAF, and EGFR genes... 

KRAS ( 190070) http //www.sangcr.ac. uk/perl/genetics/CGP/cosmic action=bygene ln=KRAS http //www.hgmd.cf.ac.uk/ac /gene. php gene=KRAS... 

Functional consequences of each mutation type vary. Generally, mutations result in either activation of the gene, typically forming an oncogene (e.g., KRAS, RET), or loss of function of a tumor suppressor gene TP53, PTEN, CDKNIA). 

These neoplasms often have TP53 gene mutations, and immunolabeling for the p53 protein has been shown to label the pleomorphic mononuclear cells but not the osteoclast-like giant cells. Additionally, genetic analyses have demonstrated that the atypical mononuclear cells harbor KRAS mutations in about 90% of these... 

The most common genetic alteration identified to date is LOH of the highly imprinted region of chromosome lip near the WT2 gene locus.Additionally, alterations in the adenomatous polyposis coli (APC)/ -catenin pathway have been reported in 50% to 80% of pancreatoblastomas.Most often, these involve the p-catenin gene (CTNNBlj. ssooo u Uke DAs, TP53 and KRAS mutations have not been detected.334.299,30i,302... 

Molecular alterations of gallbladder adenomas are fairly different than those observed in the conventional dysplasia-carcinoma sequence. Mutations of the p53 gene are virtually nonexistent in gallbladder adenomas and only rarely detected in EHBD tumors. In contrast, p53 abnormalities are quite common in flat dysplasia and invasive carcinoma. Similarly, mutation of the KRAS oncogene is detected in only 25% of gallbladder adenomas. In contrast, mutations of the -catenin gene, which are uncommon in invasive biliary carcinomas, have been detected in 60% of adenomas, mostly the pyloric gland type, and less commonly the papillary or intestinal typesA ... 

Ikeda, T., Yoshinaga, K., Suzuki, A., Sakurada, A., Ohmori, H., and Horii, A. (2000). Anticorresponding mutations of the KRAS and PTEN genes in human endometrial cancer. Oncol. Rep. 7(3), 567-570. 

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