Endogenously expressed HPV16 E6 was immunoprecipitated from HPV16 positive cervical carcinoma cells (CaSki and Siha), the co-immunoprecipitation (IP) of ING4 was monitored by the polyclonal antibody reactive to ING4, HPV negative cervical carcinoma cell line C33A was used as a negative control. The gene discussed is ING4; the disease is cervical carcinoma.