Unfavorable Prognosis and Clinical Consequences of APOBEC3B Expression in Breast and Other Cancers: A Systematic Review and Meta-analysis

Introduction: Controversy exists regarding the association of apolipoprotein B mRNA editing enzyme catalytic subunit 3B APOBEC3B, (A3B) overexpression and poor prognosis, metastasis, and chemotherapy drug resistance in cancers. Here we conducted a systematic review and meta-analysis to determine its prognostic value and clinicopathological features in breast cancer and some other malignancies.

Materials And Methods: PubMed, Scopus, Cochrane Library, Web of Science, and EMBASE were searched up to Feb 2022 for the association of A3B with breast, ovarian, gastrointestinal and lung cancers. The pooled hazard ratios with 95% confidence interval (CI) were evaluated to assess disease-free survival (DFS), overall survival (OS), and recurrence-free survival (RFS) in cancers under study.

Results: Over 3700 patients were included in this meta-survey. Elevated levels of A3B were significantly related to low OS (pooled HR = 1.30; 95% CI:1.09-1.55, P < 0.01), poor DFS (pooled HR = 1.66; 95% CI:1.17-2.35, P < 0.01) and poor RFS (HR = 1.51, 95% CI:1.11-2.04, P = 0.01). Subgroup analysis revealed that high A3B expression was associated with poor OS in lung (HR = 1.85, 95% CI: 1.40-2.45), and breast cancers (HR = 1.38, 95% CI: 1.00-1.89). High expression of A3B did not display any significant association with clinicopathologic features.

Conclusion: APOBEC3B overexpression is related to poor OS, DFS and RFS only in some cancer types and no generalized role could be predicted for all cancers.