To recognize chemoresistant tumor cells, we reviewed previous literature and summarized key chemoresistant expression patterns, including ABC transporters, DNA repair, stemness expression (EMT, Wnt/β-catenin pathway, TGFβ pathway, TNFα pathway, MAPK pathway, Notch pathway, Hedgehog pathway and BMP pathway) (6). The gene discussed is TNF; the disease is neoplasm.