[Increased expression of the c-Met receptor mRNA in gastric cancer]

Gastric cancer is one of the most common malignancies in the world. In the last decades, the attention has been focused in possible alterations of genetic factors that include proto-oncogene activation and/or the tumor suppressor gene inactivation. The product of the proto-oncogene c-MET and its ligand, hepatocyte growth factor (HGF), have been implicated in cell proliferation and migration in gastric cancer. In this study we analyzed at the molecular level, the amplification of c-Met receptor mRNA from gastric tumor tissue of patients who underwent gastrectomy, using the acid guanidinium-thiocyanate-phenol-chloroform method and the semiquantitative Reverse Transcriptase-Polymerase Chain Reaction (RT-PCR) method. It was found that high levels of c-Met receptor mRNA in tumor samples from patients are associated with greater depth of invasion in the gastric wall (r = 0.762, p < 0.01), increase in metastases to lymph nodes (r = 0.766, p < 0.01), high frequency of poorly differentiated or undifferentiated tumors (r = 0.912, p < 0.001), increase in the gastric cancer staging (r = 0.838, p < 0.001), and the overexpression, by the immunohistochemistry method (IHC) of the labeled streptavidin-biotin, of the c-Met receptor at the protein level (r = 0.858, p < 0.001). The amplification of mRNA and/or protein level overexpression of the c-Met receptor could be used as prognostic factors in gastric cancer.