On the other hand, a strong positive correlation of constitutively active STAT3 with induction of HPV16 E6 and E7 oncoproteins and a negative association with levels of p53 and pRB on HPV16-positive cervical cancer cell lines (SiHa and CaSki) and primary tumor tissues, have been reported [33]. This evidence concerns the gene TP53 and cervical carcinoma.