Furthermore, sh-NC and sh-Smad4 Hepa1-6 cells were inoculated subcutaneously in nude mice and Smad4 deficiency in Hepa1-6 cells didn't inhibit tumor growth compared with the sh-NC group, indicating that the anti-tumor effects of Smad4 mainly depended on the host's T cells, but not tumor cells (Figure S2C-D). Here, SMAD4 is linked to neoplasm.