Effects of mutations in KRAS and BRAF gene and histological parameters on the clinical course of disease in patients with metastatic colorectal cancer
Ontology highlight
ABSTRACT:
DISEASE(S): Metastatic Colorectal Cancer
PROVIDER: 2408305 | ecrin-mdr-crc |
REPOSITORIES: ECRIN MDR
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2011-03-04 | E-GEOD-27659 | biostudies-arrayexpress
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Project description:Low-grade ovarian serous carcinomas are believed to arise via an adenoma-serous borderline tumor-serous carcinoma sequence. In this study, we found that advanced-stage, low-grade ovarian serous carcinomas both with and without adjacent serous borderline tumor shared similar regions of loss of heterozygosity. We then analyzed 91 ovarian tumor samples for mutations in TP53, BRAF, and KRAS. TP53 mutations were not detected in any serous borderline tumors (n = 30) or low-grade serous carcinomas (n = 43) but were found in 73% of high-grade serous carcinomas (n = 18). BRAF (n = 9) or KRAS (n = 5) mutation was detected in 47% of serous borderline tumors, but among the low-grade serous carcinomas (39 stage III, 2 stage II, and 2 stage I), only one (2%) had a BRAF mutation and eight (19%) had a KRAS mutation. The low frequency of BRAF mutations in advanced-stage, low-grade serous carcinomas, which contrasts with previous findings, suggests that aggressive, low-grade serous carcinomas are more likely derived from serous borderline tumors without BRAF mutation. In addition, advanced-stage, low-grade carcinoma patients with BRAF or KRAS mutation have a better apparent clinical outcome. However, further investigation is needed. Low-grade ovarian serous carcinomas are believed to arise via an adenoma-serous borderline tumor-serous carcinoma sequence. In this study, we found that advanced-stage, low-grade ovarian serous carcinomas both with and without adjacent serous borderline tumor shared similar regions of loss of heterozygosity. We then analyzed 91 ovarian tumor samples for mutations in TP53, BRAF, and KRAS. TP53 mutations were not detected in any serous borderline tumors (n = 30) or low-grade serous carcinomas (n = 43) but were found in 73% of high-grade serous carcinomas (n = 18). BRAF (n = 9) or KRAS (n = 5) mutation was detected in 47% of serous borderline tumors, but among the low-grade serous carcinomas (39 stage III, 2 stage II, and 2 stage I), only one (2%) had a BRAF mutation and eight (19%) had a KRAS mutation. The low frequency of BRAF mutations in advanced-stage, low-grade serous carcinomas, which contrasts with previous findings, suggests that aggressive, low-grade serous carcinomas are more likely derived from serous borderline tumors without BRAF mutation. In addition, advanced-stage, low-grade carcinoma patients with BRAF or KRAS mutation have a better apparent clinical outcome. However, further investigation is needed.
2011-03-04 | GSE27659 | GEO
Project description:Mutational status of KRAS in CRC is used to aid patient stratification for Cetuximab treatment. However, only a subset (10-40%) of patients with wt KRAS respond. We analyzed 40 mCRC tumors for Cetuximab response using a functional ex vivo platform. In the subset of non-responsive tumors, mutational (KRAS/BRAF and PIK3CA) and expression (AREG/EREG) analysis of key genes, transcriptomic profiling and GSEA were carried out to elucidate the molecular mechanisms underlying the response. Our analysis revealed deregulation of multiple pathways, notably Notch and Erbb2 and combined blockade of these two nodes elicited significant antitumor response. These findings collectively indicate the dependence of Cetuximab insensitive mCRC tumors on Notch and Erbb2 for survival and progression.
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