We then chose the three most well-known cervical cancer cell lines, HPV16 positive SiHa and CaSki cell lines and HPV18 positive HeLa cell line, to confirm the clinical observation in vitro. As expected, CUL2 expression was higher in SiHa and CaSki cells than that in HeLa cells (Figure 1G). This evidence concerns the gene CUL2 and cervical cancer.