Gallbladder carcinoma, the most frequent malignant neoplasm of the biliary tract system, has always been considered to feature late clinical presentation and diagnosis, limited treatment options and an extremely poor prognosis. In recent years, while the incidence of gallbladder cancer has appeared to be on the increase, the available treatment methods have not greatly improved survival of the affected patients. Thus, exploring new therapeutic targets for this devastating disease is an urgent matter at present. Epidemical studies have demonstrated that the incidence of gallbladder carcinoma exhibits a distinct gender bias, affecting females two to three times more than males, pointing to crucial roles of estrogen. It is well known that estrogen acts on target tissues by binding to estrogen receptors (ERs), which are mainly divided into three subtypes, ERα, ERβ and ERγ. ERα and ERβ appear to have overlapping but also unique even opposite biological effects. As important pathogenic mediators, ERs have been considered to relate to several kinds of tumors. In gallbladder carcinoma tissue, ERs have been shown to be positively expressed, and ERs expression levels are associated with differentiation and prognosis of this cancer. Nevertheless, the exact mechanisms of estrogen inducing growth of gallbladder carcinoma remain poorly understood. On the base of the current investigations, we deduce that estrogen participates in promotion of gallbladder carcinoma by influencing the formation of gallstones, stimulating angiogenesis, and promoting abnormal proliferation. Since ERs mediate the carcinogenic actions of estrogen in gallbladder, and therapy targeting ERs may provide new directions for gallbladder carcinoma. Therefore, it should be stressed that ERs are potential therapeutic targets for gallbladder carcinoma.

Presently, no effective markers are available to facilitate gallbladder cancer (GBC) diagnosis. This study aims to explore available markers for GBC diagnosis. Clinical data of 144 GBC and 116 cholelithiasis patients were retrospectively reviewed. Logistic regression analysis was performed to evaluate GBC risk factors. A receiver operating characteristic (ROC) curve was used to assess the diagnosis value of the risk factors. By comparing the characteristic of GBC and cholelithiasis patients, the following factors exhibited statistical difference: age, gender, gallstones, total bilirubin (TB), alkaline phosphatase (ALP), aspartate aminotransferase (AST), alanine aminotransferase (ALT), platelet count (PLT), CA125 (carcinoembryonic antigen 125), and CA199 (carbohydrate antigen 199). Logistic regression analysis indicated that age [odds ratio (OR), 1.032; 95%confidence interval (95% CI), 1.004 to 1.061; P = 0.024], gender (OR, 0.346; 95% CI, 0.167 to 0.716; P = 0.004), gallstones (OR, 0.027; 95% CI, 0.007 to 0.095; P < 0.001), ALP (OR, 1.003; 95% CI, 1.000 to 1.006; P = 0.032), TB (OR, 1.004; 95% CI, 1.000 to 1.009; P = 0.042), and CA125 (OR, 1.007; 95% CI, 1.002 to 1.013; P = 0.011) were independent risk factors for GBC. According to the ROC curve, CA125 [area under curve (AUC), 0.720], ALP (AUC, 0.713), TB (AUC, 0.636), and age (AUC, 0.573) were valuable diagnosis markers. Additionally, based on the independent risk factors, the GBC diagnosis model was established. Age, TB, ALP, and CA125 can be used as auxiliary diagnosis factors of GBC. The diagnosis model provides a quantitative tool for GBC diagnosis when comprehensively considering various risk factors.