The renin-angiotensin system blockers as adjunctive therapy for cancer: a meta-analysis of survival outcome

OBJECTIVE: The renin-angiotensin system blockers (RASBs), including angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin II receptor blockers (ARBs), are widely used to reduce cardiovascular disease (CVD) events. Accumulating pre-clinical and clinical studies suggested that RASBs possesses anti-carcinogenic properties, and their use is associated with favorable outcomes in several type cancers. To conduct a meta-analysis to evaluate the effect of adjunctive therapy of renin-angiotensin system blockers combined with chemotherapeutic agents in cancer patients. MATERIALS AND METHODS: Data from a total of 2436 patients from 7 retrospective studies investigating chemotherapeutic agents in combination with RASBs agents versus chemotherapeutic agents were included in this meta- analysis. Publication bias was assessed by the Begg's Test, Egger's test and funnel plot. Subgroup analysis was conducted when the chemotherapeutic agents were the same. RESULTS: A significant reduction in overall mortality in favor of chemotherapeutic agents in combination with RASBs agents was observed, hazard ratio (HR) 0.80 (95% CI: 0.69-0.92); there was a significant decrease in the risk of disease progression in favor of chemotherapeutic agents in combination with RASBs regimens, HR 0.79 (95% CI: 0.66-0.94), compared with those who only used chemotherapeutic agents. Subgroup analysis indicated that platinum-based agents plus ACEI/ARB could increase significantly the survival outcome (HR = 0.56; 95% CI: 0.38-0.82). CONCLUSIONS: Our results suggest that RASBs combined with chemotherapeutic agents may improve outcomes in multiple types' cancer patients. More research and well-designed, rigorous, large clinical trials are required to address these issues.