Tumor cells HCT116 p53+/+, HCT116 p53−/−, U87, and U251 were selected for cell viability experiments, and the results of cell activity experiments showed that the tumor suppressive activity of the staple peptide was significantly higher than that of the template straight-chain peptide, indicating that the enhanced activity of the staple peptide was related to the increase in helicity. This evidence concerns the gene TP53 and neoplasm.