부산대학교 도서관

NUCLEAR TO CYTOPLASMIC COMPARTMENT SHIFT OF THE P33: AIMS:: Cutaneous malignant melanoma is an unpredictable neoplasm. Studies of cell cycle and proliferation-associated proteins may help in the understanding of the genesis of melanomas. The tumour suppressor gene TP53 has been shown to be involved in melanomas. However, the incidence of TP53 malfunction in cutaneous melanoma is unclear, and other regulators of cell cycle control are likely to be involved in both the development and progression of melanocytic neoplasia. A candidate is the ING1 gene, which co-operates with TP53 in growth suppression and apoptosis. Thus loss of ING1 function may have similar consequences to loss of TP53 function and may contribute to tumorigenesis. Therefore we have studied the expression of p33 protein in cutaneous melanocytic neoplasia. METHODS AND RESULTS:: Sixty-seven melanocytic lesions were studied by immunohistochemistry for the expression of p33 . In our series there was loss of nuclear p33 expression in invasive malignant melanoma compared with normal cutaneous melanocytes or the melanocytes of benign melanocytic naevi. This was associated with an enhancement of cytoplasmic p33 expression which was particularly prominent in invasive malignant melanoma. CONCLUSIONS:: Cytoplasmic immunostaining for p33 using MAb GN2 is strongly associated with `activated' melanocytic lesions; therefore it is possible that this MAb could be of value in diagnostic practice. Furthermore, the reduction in p33 expression and perhaps translocation from the nucleus to the cytoplasm may play a central role in the development and progression of melanomas.