PIK3R1 and ovarian cancer: Several frequent mutations, including Y504D, Q552K, I559N, D560Y, N564D, D569Y, R574T, T576del, W583del, N595K, and N600H mutants may regulate the iSH2 domain for the creation of multiple cancer like breast, endometrium and ovarian cancer particularly at amino acids 456-469 and 564-575 [70, 72–74] in PIK3R1 protein.