Aldehyde dehydrogenase 1 as a predictor of the neoadjuvant chemotherapy response in breast cancer: A meta-analysis

BACKGROUND: Many reports suggest that aldehyde dehydrogenase 1 (ALDH1) expression is associated with poorer neoadjuvant chemotherapy (NAC) response in patients with breast cancer; however, the prognostic value of this enzyme in cancer has yet to be confirmed. Therefore, we conducted a meta-analysis of related studies to investigate the relationship between ALDH1 expression and the NAC response in breast cancer patients. METHODS: PubMed, Web of Science, ScienceDirect, Cochrane Library, and EMBASE were searched for potentially eligible literature. The study characteristics and relevant data were extracted. Odds ratios (ORs) with 95% confidence intervals (CIs) were pooled to estimate the prognostic role of ALDH1 in the NAC response in patients with breast cancer. The robustness of our results was confirmed by sensitivity and publication bias analyses. RESULTS: Pooled meta-analysis of 10 eligible studies including 1081 patients indicated an association between high ALDH1 expression and poor NAC responses (pooled OR = 0.44, 95% CI: 0.25–0.77, P = .004) with low significant heterogeneity (I(2) = 55.1%, P = .018). During subgroup analyses, we found that the recipient sample size presents a potential source of heterogeneity. Begg funnel plot and Egger test showed no possible publication bias. Sensitivity analysis suggested that the pooled OR was robust. CONCLUSION: Our results suggested that higher ALDH1 expression is associated with poorer NAC responses in patients with breast cancer. However, given the limited number of studies analyzed in this work, more studies are necessary to verify our results.