Expression of ERα36 in gastric cancer samples and their matched normal tissues.

Estrogen receptor α36 (ERα36) is believed to mediate membrane-initiated effects of estrogen signaling, and promote cell growth and resistance to tamoxifen treatment. However, few studies are available regarding ERα36 expression in gastric cancer. In the present study, we evaluated the expression of ERα36, as well as estrogen receptor α66 (ERα66), in gastric cancer and its correlation with clinicopathological parameters. Real-time polymerase chain reaction (PCR) was applied to detect the expression of ERα66 and ERα36 mRNA in 45 pairs of samples of gastric cancer tissues and matched normal tissues. The ΔΔCT method was used to evaluate the relative quantity of target mRNA expression. Among the 45 pairs of samples of gastric cancer tissues and matched normal tissues adjacent to the tumor, the ERα36 mRNA levels in normal tissues were significantly higher than those observed in gastric cancer tissues (p=0.040). Additionally, the expression of ERα66 mRNA levels between gastric cancer tissues and matched normal tissues had no statistically significant difference. We confirmed that ERα36 mRNA was expressed in the four gastric cancer cell lines, and ERα66 mRNA was expressed in two of the four gastric cancer cell lines. According to the tissue and cell findings, it was suggested that the expression level of ERα36 is greater than that of ERα66 in gastric cancer. In conclusion, the expression of ERα66 and ERα36 in gastric cancer tissues and cells was confirmed in this study. A decreased expression of ERα36 mRNA in gastric cancer tissues may be one of the factors affecting tumorigenesis in gastric cancer patients.