Oxeiptosis-associated transcriptional states, immune heterogeneity, and oxidative-stress susceptibility in triple-negative breast cancer

Background Triple-negative breast cancer (TNBC) exhibits substantial variation in treatment response. In the phase 2 NeoSAC trial, higher baseline oxeiptosis-associated transcriptional activity was associated with pathological complete response (pCR). However, the malignant-cell and immune features underlying this transcriptional state remain poorly defined, as do the molecular factors that influence cellular susceptibility to oxidative stress. Methods We integrated single-cell and bulk transcriptomic analyses to characterize oxeiptosis-associated tumor states and immune features in TNBC. CellChat was used to infer candidate intercellular communication patterns. An oxeiptosis-associated prognostic model was developed and evaluated in breast cancer cohorts. In MDA-MB-231 cells, ALG3 loss- and gain-of-function experiments were used to assess cellular responses to the KEAP1 activator VVD-130037. We also examined the effects of VVD-130037 alone and in combination with docetaxel on tumor-cell growth. Results TNBCs with higher oxeiptosis-associated transcriptional scores showed greater representation of memory T cells and selected dendritic and inflammatory myeloid populations. CellChat inferred differences in candidate MIF-related, SPP1-CD44, and MHC-associated communication patterns between the score-defined groups, suggesting the coexistence of immune engagement and regulatory features. A five-gene model comprising MAL2, TYMP, LIMCH1, ALG3, and PDLIM4 showed prognostic value across breast cancer cohorts, with moderate performance that varied between cohorts. VVD-130037 increased intracellular ROS and reduced AIFM1 Ser116 phosphorylation. N-acetyl-L-cysteine attenuated these responses and the accompanying growth inhibition, whereas z-VAD-fmk did not provide comparable protection against growth inhibition. ALG3 depletion reduced VVD-130037-induced ROS accumulation, attenuated AIFM1 Ser116 dephosphorylation, and decreased sensitivity to VVD-containing treatment. ALG3 overexpression promoted the VVD-associated decrease in AIFM1 Ser116 phosphorylation. VVD-130037 combined with docetaxel produced greater growth inhibition than either agent alone. Conclusion Oxeiptosis-associated transcriptional states were associated with distinct malignant-cell and immune features in TNBC. In MDA-MB-231 cells, ALG3 expression modified the cellular response to VVD-130037-induced oxidative stress. These findings warrant further investigation in independent clinical and experimental models.