TP53 and cancer: For example, elevated expression of Poly beta had been found in drug-resistant cancer cells,160 and knockdown of Poly beta by siRNA resensitized cancer cells to cisplatin;159 upregulated poly kappa had also been examined in lung cancer161 and inactivation of p53 promoted the expression of poly kappa.162 The genomic instability caused by tolerance of mutations was one of the main features of cancer.163