Transforming growth factor-β (TGF-β), produced not only by malignant cells but also by immunosuppressive immune subsets such as regulatory T cells (Tregs), myeloid-derived suppressor cells (MDSCs), and tumor-associated macrophages (TAMs), plays a pivotal role in restraining NK cell activity in ovarian cancer (12). The gene discussed is TGFB1; the disease is neoplasm.