Effect of metformin use on the risk and prognosis of endometrial cancer: a systematic review and meta-analysis

Abstract

BackgroundPrevious studies have suggested that metformin may be useful for preventing and treating endometrial cancer (EC), while the results have been inconsistent. This systematic review and meta-analysis aimed to investigate the association between metformin use and risk and prognosis of patients with EC.MethodsPubMed, Embase, and the Cochrane Library databases were searched for observational studies evaluating the effect of metformin on EC prevention or treatment. The odds ratio (OR) was used for analyzing risks, and the hazard ratio (HR) was used for analyzing survival outcomes. A random-effects model was used for data analysis.ResultsSeven studies reported data on EC risk. The pooled results suggested that metformin was not significantly associated with a lower risk of EC [OR = 1.05, 95% confidence interval (CI) 0.82–1.35, P = 0.70]. For patients with diabetes, metformin showed no advantage in reducing the EC risk compared with other interventions (OR = 0.99, 95% CI 0.78–1.26, P = 0.95). Further, seven studies were included for survival analysis. The pooled data showed that metformin could significantly improve the overall survival of patients with EC (HR = 0.61, 95% CI 0.48–0.77, P < 0.05) and reduce the risk of EC recurrence (OR = 0.50, 95% CI 0.28–0.92, P < 0.05) Finally, we noted metformin was associated with significantly improving the overall survival of EC patients among diabetes (HR = 0.47; 95%CI 0.33–0.67, P < 0.05).ConclusionsThis meta-analysis did not prove that metformin was beneficial for preventing EC. However, metformin could prolong the overall survival of patients with EC and reduce their risk of cancer relapse.Electronic supplementary materialThe online version of this article (10.1186/s12885-018-4334-5) contains supplementary material, which is available to authorized users.

Recycling the Purpose of Old Drugs to Treat Ovarian Cancer

“…Epidemiological studies reveal that cancer-related mortality rate is significantly lower in metformin patient users and that survival rates is improved in many types of cancer patients, i.e., colorectal, pancreatic, breast, liver and endometrial cancers [ 106 , 107 ]. A recent study demonstrated that metformin significantly prolonged the OS (HR = 0.61; 95% CI = 0.48–0.77) and reduced recurrence risk (HR = 0.50; 95% CI = 0.28–0.92) in endometrial cancer [ 108 ]. Regarding endometrial cancer, results showed that metformin amplify the effects of paclitaxel by blocking mTOR-signalling pathway [ 109 ].…”

Prevention Strategies in Endometrial Carcinoma

“…Randomised biomarker studies have so far failed to demonstrate a reduction in endometrial proliferation with 2–16 weeks of metformin treatment [ 38 , 39 ]. Similarly, metformin has not been shown to reduce endometrial cancer risk (OR 1.05, 95% CI 0.82–1.35, p = 0.7), but may improve risk of recurrence or overall survival [ 40 ].…”

CircRNA hsa_circRNA_0001776 inhibits proliferation and promotes apoptosis in endometrial cancer via downregulating LRIG2 by sponging miR-182

“…Endometrial cancer (EC), mainly occurred in postmenopausal women, is one of the most common malignancies of the female reproductive system with the incidence of about 1/10,000 in worldwide [ 1 ]. EC is conventionally classified into type I (estrogen-dependent) EC and type II (estrogen-nondependent) EC according to molecular genetic features and clinicopathological features, and grades 1 and 2 are regarded as “type I”, while grade 3 is regarded as “type II” [ 2 , 3 ].…”