Abstract
BACKGROUND: To assess the predictive value of drug-resistant proteins - serum glutathione S-transferase (GST-â), P-glycoprotein (PGP), P53, Ki-67 - in triple-negative breast cancer (TNBC) and their role in chemotherapy resistance. This systematic review and meta-analysis aimed to explore their clinical relevance for improving TNBC treatment outcomes. METHODS: We systematically searched PubMed, Web of Science, CNKI, WanFang, and VIP databases for studies from 2010 to 2024. Studies meeting predefined inclusion and exclusion criteria were selected. Data extraction and quality assessment were performed by two independent researchers. Meta-analysis was conducted using RevMan 5.3 software. RESULTS: Seven studies were included, involving 1,772 patients, with 745 TNBC cases and 1,027 non-TNBC cases. Meta-analysis showed that in TNBC compared to non-TNBC, the expression rates of GST-â [O R= 3.41, 95% CI (2.21, 5.25), P< 0.00001], PGP [O R= 1.87, 95% CI (1.17, 2.98), P= 0.008], P53 [O R= 3.65, 95% CI (2.25, 5.91), P< 0.00001], and Ki-67 [O R= 1.19, 95% CI (0.54, 1.84), P= 0.0004] were significantly elevated, indicating higher drug resistance. However, no significant differences were found in Topo I, II, or III expression. Additionally, TNBC patients had poorer disease-free survival (DFS) [O R = 0.30, 95% CI (0.15, 0.59), P=0.0005] and overall survival (OS) [O R=0.17, 95% CI (0.11, 0.28), P<0.00001] compared to non-TNBC patients. CONCLUSIONS: The elevated expression of drug-resistant proteins GST-â, PGP P53, and Ki-67 in TNBC suggests that these biomarkers are closely associated with chemotherapy resistance. Monitoring their levels during treatment may help guide more effective clinical strategies for managing TNBC. The findings emphasise the need for personalised therapeutic approaches based on protein expression profiles to improve clinical outcomes for TNBC patients.