Tumor regression grades, K-RAS mutational profile and c-MET in colorectal liver metastases

The potential therapeutic and prognostic impacts of the c-MET/HGF signaling pathway in colorectal cancer

Colorectal cancer (CRC) is the third most common cancer and a common cause of cancer-related mortality globally. In spite of the improvements in the early diagnosis of CRC, approximately one-third of patients develop metastasis and then have a very poor survival rate. The mesenchymal-epithelial transition factor (c-MET) is a tyrosine kinase cell surface receptor activated by hepatocyte growth factor (HGF). Activation of c-MET/HGF signaling pathway regulates a variety of biological processes including cell motility, cell proliferation, angiogenesis, the epithelial-to-mesenchymal transition, and the development and progression of cancer cells. Recent studies have suggested that the c-MET/HGF signaling pathway is involved in the carcinogenesis of CRC. In this review, we summarize the main findings of recent studies investigating the role of c-MET/HGF signaling pathway in CRC and the potential of the c-MET/HGF signaling pathways in the diagnosis and treatment of CRC. © 2019 IUBMB Life, 2019.

Upregulation of c-mesenchymal epithelial transition expression and RAS mutations are associated with late lung metastasis and poor prognosis in colorectal carcinoma

The present study aimed to investigate whether c-mesenchymal epithelial transition factor (C-MET) overexpression combined with RAS (including KRAS, NRAS and HRAS) or BRAF mutations were associated with late distant metastases and the prognosis of patients with colorectal cancer (CRC). A total of 374 patients with stage III CRC were classified into 4 groups based on RAS/BRAF and C-MET status for comprehensive analysis. Mutations in RAS/BRAF were determined using Sanger sequencing and C-MET expression was examined using immunohistochemistry. The associations between RAS/BRAF mutations in combination with C-MET overexpression and clinicopathological variables including survival were evaluated. In addition, their predictive value for late distant metastases were statistically analyzed via logistic regression and receiver operating characteristic analysis. Among 374 patients, mutations in KRAS, NRAS, HRAS, BRAF and C-MET overexpression were observed in 43.9, 2.4, 0.3, 5.9 and 71.9% of cases, respectively. Considering RAS/BRAF mutations and C-MET overexpression, vascular invasion (P=0.001), high carcino-embryonic antigen level (P=0.031) and late distant metastases (P<0.001) were more likely to occur in patients of group 4. Furthermore, survival analyses revealed RAS/BRAF mutations may have a more powerful impact on survival than C-MET overexpression, although they were both predictive factors for adverse prognosis. Further logistic regression suggested that RAS/BRAF mutations and C-MET overexpression may predict late distant metastases. In conclusion, RAS/BRAF mutations and C-MET overexpression may serve as predictive indicators for metastatic behavior and poor prognosis of CRC.