At the same time, it has also been found that phosphatidylinositol 3-kinase (PI3K) will be activated in human keratinocytes exposed to long- and medium-wave ultraviolet and the expression of phosphorylated ribosomal protein S6 kinase 1 (S6K1) in human keratinocytes can be suppressed by rapamycin [13], suggesting that the mTOR signaling pathway may play a role in the occurrence of human skin epithelial tumors. This evidence concerns the gene MTOR and epithelial skin neoplasm.