BCL11B predetermines a persister state in breast cancer that is reversed by TNFα

The frequent development of chemoresistance in cancer presents a significant clinical challenge, yet the underlying causes for heterogeneous drug responses remain largely elusive. Here, we systematically assessed the cellular differentiation status of human breast cancer cells utilizing single-cell atlases and identified a distinct population of immature basal-like cancer cells marked by BCL11B. Notably, higher levels of BCL11B+ cancer cells are significantly associated with early relapse in breast cancer patients who received chemotherapy. Functioning as a central regulator, BCL11B delineates an immature cell state that preferentially transitions to a drug-resistant persister state during treatment through multiple pre-existing and adaptive drug-resistance programs. Importantly, the cytokine tumor necrosis factor alpha (TNFα) is revealed as a natural inhibitor of BCL11B and can directly reverse the emergence of chemoresistant persister cells. Therefore, we identify BCL11B as an unappreciated pre-determinant of drug response and a therapeutic target for a subset of breast cancer patients at high risk of developing chemoresistance.