Correlation between solute carrier transporter 22A3 gene rs7758229 polymorphism and prognosis of pancreatic cancer

Abstract

Objective To investigate the relationship between solute carrier transporter 22A3 (SLC22A3) gene rs7758229 polymorphism and prognosis of pancreatic cancer. Methods One hundred patients with resectable pancreatic cancer who underwent surgery were admitted to our hospital from March 30, 2014 to March 30, 2016 were selected. There were were 61 male and 39 female patients, aging from 35 to 79 years with a median age of (49.1±5.7) years. The location included head and neck of the pancreas (n=66), body and tail of pancreas (n=34). According to the 7th American Joint Committee on Cancer (AJCC) Pancreatic Cancer Staging System, 19 cases were in stage I, 56 cases were in stage Ⅱ and 25 cases in stage Ⅲ. On the 2nd day after admission, 5 ml of fasting venous blood was taken, and the polymorphism of SLC22A3 gene rs7758229 was detected by DNA extraction kit and sequencing method. The patients were followed up and the end point was all-cause death. The correlation between polymorphism of rs7758229 and the prognosis of pancreatic cancer, and the factors affecting the overall survival (OS) of the patients were analyzed. The date analysis was conducted by SPSS 25.0; the gene type distribution deviation was tested by Hardy-Weinberg equilibrium, the correlation analysis of clinical date was analyzed by χ2 test analysis. The correlation between polymorphism of rs7758229 and the prognosis of pancreatic cancer, and the factors affecting the OS of the patients were analyzed by by Kaplan- Meier method and Cox model respectively. Results There were 28 cases (28.0%) of GG type, 51 cases (51.0%) of GT type, and 21 cases (21.0%) of TT type. The rs7758229 mononucleic acid polymorphism was significantly correlated with the degree of tumor differentiation and clinical stage (χ2=10.209, 10.826, P<0.05). Six patients were lost to follow-up (2 patients with GG, 3 patients with GT, and 1 patient with TT) with a median follow-up of 46 months. There were 73 deaths. Kaplan-Meier analysis and Log-rank test showed that overall survival (OS) was significantly shortened in patients with rs7758229 TT as compared with that in those with rs7758229 GG (Log-rank: χ2=11.254, P<0.05). Cox proportional hazard model results showed that rs7758229 mononuclear acid polymorphism [TT type/GG type, P<0.05, odds ratio (OR): 2.357, 95% confidence interval (CI): 1.524-6.317], TNM stage (P<0.05, OR: 1.194, 95%CI: 0.031-3.491), age (P<0.05, OR: 1.354, 95%CI: 1.067-4.357), degree of tumor differentiation (P<0.05, OR: 1.687, 95%CI: 1.108-4.217), and margin situation (P<0.05, OR: 1.947, 95%CI: 1.354-5.218) were independent prognostic factors influencing OS in patients with pancreatic cancer (P<0.05). Conclusion The rs7758229 polymorphism of SLC22A3 gene is associated with the survival rate of pancreatic cancer. The OS of TT patients is shorter. Key words: Solute carrier transporter 22A3 gene; Mononucleotide polymorphism; Pancreatic cancer; Overall survival