Relationship between esophageal cancer-related gene 2 polymorphism and esophageal squamous cell carcinomas in Kazakhs and Hans of Xinjiang

In recent years, many studies have focused on the novel esophageal cancer-related gene 2 (ECRG2), which might be important in esophageal cancer development. The aim of this study is to investigate the relationship between ECRG2 short tandem repeat (STR) polymorphism and susceptibility to esophageal squamous cell carcinomas (ESCCs) in Kazakhs and Hans in Xinjiang. ECRG2 genotypes were detected by PCR-SSCP in 178 cases of esophageal carcinomas and 153 blood samples from the Kazakh and Han population. In Kazakhs and Hans, the frequencies of ECRG2 STR genotypes TCA3/TCA3, TCA4/TCA4, and TCA3/TCA4 were 47.8%/8.7%, 43.5%/67.9%, and 7.1%/25.0% in esophageal carcinomas with metastasis, respectively; and 14.1%/38%, 47.9%/14.3%, and 44.6%/41.1% in carcinomas without metastasis, respectively. A significant difference was observed between the groups with metastasis and without metastasis (Kazakh: χ²=13.77, P<0.01; Han: χ²=26.183, P<0.01). Compared with patients who carried the TCA4/TCA4 genotype, those who carried the TCA3/TCA3 genotype were at an increased risk of ESCC, with the adjusted odds ratios being 4.06 (95% confidence interval (CI), 1.69-9.74) in Kazakhs and 3.25 (95% CI, 1.25-8.45) in Hans. Our findings suggested that subjects who carried the TCA3/TCA3 genotype are at an increased risk of ESCC and metastasis compared with those who carried the TCA4/TCA4 genotype.