PIK3CA and cervical squamous intraepithelial neoplasia: Additionally, the mutation rate of ARID1A and PIK3CA in TCGA-STAD cohort were also higher in EBV and MSI molecular subtypes, which was correlated with an elevated TMEscore and immunotherapeutic response as compared with CIN and GS subtypes (ARID1A: p<2.2×10−16; PIK3CA: p<2.2×10−16; χ2 test; online supplemental figure S7C, D).