Also, TGF-β has been found to induce exhaustion of effector memory T cells in B-cell non-Hodgkin’s lymphoma and NK cells in liver cancer (11, 25); therefore, it is also interesting to confirm whether low-risk HPV infection could induce tumorigenic cells to produce TGF-β or other factors that increase exhaustion of cytotoxic cells in our future study. This evidence concerns the gene TGFB1 and liver cancer.