Multi-omics profile of exceptional long-term survivors of AJCC stage III triple-negative breast cancer.

Abstract

Objective: Triple-negative breast cancer (TNBC) is a highly aggressive subtype that lacks targeted therapies, leading to a poorer prognosis. However, some patients achieve long-term recurrence-free survival (RFS), offering valuable insights into tumor biology and potential treatment strategies.

Methods: We conducted a comprehensive multi-omics analysis of 132 patients with American Joint Committee on Cancer (AJCC) stage III TNBC, comprising 36 long-term survivors (RFS≥8 years), 62 moderate-term survivors (RFS: 3-8 years), and 34 short-term survivors (RFS<3 years). Analyses investigated clinicopathological factors, whole-exome sequencing, germline mutations, copy number alterations (CNAs), RNA sequences, and metabolomic profiles.

Results: Long-term survivors exhibited fewer metastatic regional lymph nodes, along with tumors showing reduced stromal fibrosis and lower Ki67 index. Molecularly, these tumors exhibited multiple alterations in genes related to homologous recombination repair, with higher frequencies of germline mutations and somatic CNAs. Additionally, tumors from long-term survivors demonstrated significant downregulation of the RTK-RAS signaling pathway. Metabolomic profiling revealed decreased levels of lipids and carbohydrate, particularly those involved in glycerophospholipid, fructose, and mannose metabolism, in long-term survival group. Multivariate Cox analysis identified fibrosis [hazard ratio (HR): 12.70, 95% confidence interval (95% CI): 2.19-73.54, P=0.005] and RAC1 copy number loss/deletion (HR: 0.22, 95% CI: 0.06-0.83, P=0.026) as independent predictors of RFS. Higher fructose/mannose metabolism was associated with worse overall survival (HR: 1.30, 95% CI: 1.01-1.68, P=0.045). Our findings emphasize the association between biological determinants and prolonged survival in patients with TNBC.

Conclusions: Our study systematically identified the key molecular and metabolic features associated with prolonged survival in AJCC stage III TNBC, suggesting potential therapeutic targets to improve patient outcomes.