MAPK1 and cervical squamous intraepithelial neoplasia: In light of the aforementioned literature [32], a comparison was made of the transition from CIN to MIC and CESC, showing that PIK3CA was altered in MIC and CESC either by mutation or amplification but not in CIN, explicitly indicating that driving mutations such as PIK3CA, TP53 and MAPK1 were needed in the transition from CIN to MIC/CESC in addition to human papilloma virus (HPV) infection.