Effect of ribonucleotide reductase M1 expression on overall survival in patients with pancreatic cancer receiving gemcitabine chemotherapy: A literature-based meta-analysis

What is known and objectiveThe prognostic value of ribonucleotide reductase M1 (RRM1) in patients with pancreatic cancer receiving gemcitabine chemotherapy has been evaluated in several studies. However, the conclusions remain controversial. MethodsBy searching the PubMed and Embase databases, we conducted a meta-analysis to evaluate the prognostic significance of RRM1 expression in patients with pancreatic cancer receiving gemcitabine chemotherapy. Studies were pooled, and the hazard ratio (HR) and its corresponding 95% confidence interval (CI) were calculated. ResultsNine relevant articles were included for this meta-analysis study. Our results revealed that the high-RRM1 expression patients had significantly poorer overall survival (HR=1.70, 95% CI=1.33-2.16, P-heterogeneity=.061, I-2=44.8%) and disease-free survival (HR=1.84, 95% CI=1.56-2.18, P-heterogeneity=.669, I-2=0%) than the low-RRM1 expression patients. Furthermore, a statistically significant association between RRM1 expression and OS was found among both Japanese (HR=1.80, 95% CI=1.36-2.37, P-heterogeneity=.843, I-2=0%) and American patients (HR=1.76, 95% CI=1.60-1.94, P-heterogeneity=.439, I-2=0%). What is new and conclusionIn conclusion, the expression of RRM1 can be considered a predictor of poor survival in patients with pancreatic cancer receiving gemcitabine chemotherapy. RRM1 expression assessment could provide more detailed information for patients with pancreatic cancer and could be used to optimize therapeutic schemes.