CDKN2A and cervical carcinoma: It is not clear yet why in one and the same cervical cancer sample the protein p16INK4a (normally showing its activity in nuclei) may be detected but in a cytoplasm in the majority of cells while in a number of cells both in nuclei and cytoplasm, why in some cervical cell cultures it is found solely in cytoplasm and in other cervical cell lines – in nuclei also.