Here, we demonstrate that high RAD18 expression not only facilitates a highly stem-cell phenotype, which in its turn facilitates the proliferation of TNBC, but also that its cytokine byproduct, TGF-β, promotes M2-like TAM polarization and feedback activation of RAD18 in tumor cells to enhance tumor stemness. The gene discussed is TGFB1; the disease is neoplasm.