In vitro, VEGF-A induced a resistance toward cetuximab cytotoxicity on three KRAS and NRAS wild type colon cancer cell lines in a VEGFR2 and Stat-3-dependent manner.
Female patients and older group harbored a higher KRAS mutation (P = 0.018 and P = 0.031, respectively); BRAF (V600E) mutation showed a higher frequency in colon cancer and poor differentiation tumors (P = 0.020 and P = 0.030, respectively); proximal tumors appeared a higher PIK3CA mutation (P<0.001) and distant metastatic tumors shared a higher NRAS mutation (P = 0.010).
To further evaluate sporadic colon carcinoma risk associated with rare HRAS1 VNTR alleles, the relationship with microsatellite instability and with HRAS1 VNTR instability.