Overexpression of G6PD is associated with high risks of recurrent metastasis and poor progression-free survival in primary breast carcinoma

BACKGROUND: The present study aimed to investigate the expression of CYP27A1, CYP7B1, insulin-like growth factor-1 (IGF-1), glucose-6-phosphate-dehydrogenase (G6PD), glutathione S-transferase P1 (GSTP1), and pyruvate kinase isoform M2 (PKM2) in breast carcinoma tissue and evaluate their prognostic value for progression-free survival (PFS) and overall survival (OS). METHODS: A total of 20 patients treated with surgery for primary breast carcinoma were enrolled: 10 cases diagnosed with recurrent metastasis (A), along with their corresponding metastases specimen (A(M)) and 10 cases with no evidence of recurrence or metastasis (B). Baseline characteristics of patients including age, lymph node metastasis, molecular subtypes, tumor staging and size, and pathological classification were all collected. Immunohistochemistry was performed to detect the protein expression in tumor specimens. RESULTS: Elevated G6PD protein levels were noted in group A compared with group A(M) and B (both P < 0.05), and PKM2 expression was also higher in group A when compared to group A(M) (P = 0.019), but similar with group B (P > 0.05). No association between clinicopathological parameters and the two proteins expression was observed. The G6PD protein expression was strongly associated with PFS of breast carcinoma patients (P = 0.021) but not for OS. According to the Kaplan-Meier analysis, mean PFS time of patients with G6PD-negative and G6PD-positive expression tumor were 71.36 ± 6.53 and 32.25 ± 5.67 months, respectively (P = 0.002). CONCLUSIONS: The G6PD protein could be served as a potential prognostic biomarker for primary breast carcinoma, and overexpression of G6PD protein predicted a high risk of recurrent metastasis and poor PFS during follow-up.