Distinctive interrelation of p53 with SCO2, COX, and TIGAR in human gastric cancer

p53, widely known as a tumor-suppressing gene, has recently been reported to regulate glucose metabolism in human cancers through the synthesis of cytochrome c oxidase 2 (SCO2), cytochrome c oxidase complex (COX), and TP53-induced glycolysis and apoptosis regulator (TIGAR). In this study, we investigated the interrelations of the aforementioned proteins, particularly in human gastric cancer, with cancer progression, other clinicopathological parameters, and patient outcomes.

One hundred and ten cases of primary gastric cancer occurring from June 2006 to June 2009 were investigated and classified into two groups according to the intensity of immunohistochemical staining for p53, SCO2, COX, and TIGAR. The clinicopathological data were organized and analyzed based on electronic medical records.

In accordance with previous reports, the expression of p53 showed an inverse correlation with the expression of TIGAR (p=0.032) in gastric cancer cells. However, the expression of SCO2 and COX were not shown to be associated with the regulatory role of p53, unlike TIGAR expression. Nevertheless, a significantly high recurrence rate was found in a patient group with high COX expression (p=0.012).

This study demonstrated that a high p53 expression could be associated with the promotion of glycolysis in gastric cancer via the modulation of TIGAR expression. In addition, a high COX expression appeared to be interrelated with poor prognosis of gastric cancer. However, further studies regarding the underlying molecular interactions are required to provide more evidence to propose a novel mechanism that explains our findings in gastric cancer.