PIK3CA and anal squamous cell carcinoma: Chung et al. (2016) analyzed anal squamous cell carcinomas positive for HPV 16 and 18 and reported alterations in genes involved in DNA repair, chromatin remodeling, and receptor tyrosine kinase signaling, as well as modifications in the copy numbers of genes involved in stem cell self-renewal and maintenance, cell growth, survival, proliferation, lethality and angiogenesis (SOX2, MYC, RICTOR, and PIK3CA) [159].