SQSTM1 and neoplasm: Furthermore, knockdown of p62 significantly reduced the phosphorylation of mTORC1 (p-mTOR) in HCC cells and inhibited the viability of HCC cells in vitro (Fig. 1D and Supplemental 1B) and tumor growth in a xenograft mouse model (Fig. 1E–G and Supplemental Fig. 1E).