Levels, phosphorylation status and cellular localization of translational factor eIF2 in gastrointestinal carcinomas

The level of expression and the phosphorylation status of the alpha subunit of initiation factor 2 (eIF2 alpha) protein have been determined by comparing samples from human stomach, colon and sigma-rectum carcinomas with normal tissue from the same patients. The unphosphorylated and phosphorylated levels of cytoplasmic eIF2 alpha, as well as the percentage of phosphorylated factor over the total, were significantly higher in stomach, colon and sigma-rectum tumours compared with normal tissue. The expression of this factor was also studied by using immunocytochemical methods, where redistribution towards the nucleus in tumour cells as compared with normal tissue was observed. Our results support a likely implication of eIF2 alpha in gastrointestinal cancer.