ONECUT2 governs the POU6F2-beta-catenin axis to modulate cancer stemness and drives the CCL28-dependent pathway for macrophage polarization in breast cancer

Cancer stem cells (CSC) and the immunosuppressive microenvironments are key drivers of breast cancer (BC) progression and drug resistance. However, the molecular mechanisms by which One Cut Homeobox 2 (ONECUT2) governs CSC and the tumor immune microenvironment (TIME) remains largely unknown. Given the critical knowledge gap, we sought to investigate ONECUT2’s regulatory impact on CSC properties and TIME profiles using breast cancer cell lines, animal models, and clinical specimens. Here, we demonstrated that ONECUT2, a core transcription factor, mediates CSC characteristics and reprograms the TIME to drive macrophage polarization to the M2-type, a tumor-promoting state. Mechanistically, ONECUT2 inhibition transcriptionally activated POU6F2, which subsequently triggered beta-catenin, thereby enhancing CSC properties and chemoresistance in BC. With respect to modulating the immune microenvironment, ONECUT2 can govern macrophage polarization, identifying CCL28 as a transcriptional target of ONECUT2 required for M2-type macrophage polarization, and CCR10 as a key receptor involved in immune modulation. These findings highlight the critical involvement of ONECUT2 in modulating BC stemness via targeting the POU6F2-beta-catenin axis and managing macrophage polarization to M2 phenotype through the CCL28-CCR10 pathway. Our study suggests that ONECUT2 modulates cancer stemness and the immune microenvironment, and that targeting it along its downstream axis may provide an effective approach for BC treatment.