WWTR1 and cervical carcinoma: Interestingly, when compared to immortalised but non-transformed keratinocytes (HaCaT cells) and HPV negative (-) cervical cancer cells (C33A), we only observed a significant increase in TAZ protein levels in HPV18+ (HeLa and C4-1) and HPV45+ (HPV18-related alpha-7 species) (MS751) cell lines (Fig. 1D).