Aldersley et al. (2021) analyzed anal squamous cell carcinomas associated with HPV 16 and 18 infections and reported that viral genome integration is associated with the silencing of BRCA2; the DNA damage response genes FOXO1, RB1, ATR, FANCD2, FHIT, MLH1, SETD2 APC, MSH3, PARP3, RAD18, RAD50, and XPC; and the amplification of protooncogenes (CCND1, MYC, NOTCH1, TERT, and PIK3CA) [142]. This evidence concerns the gene PIK3CA and anal squamous cell carcinoma.