|Budget Amount *help
¥1,500,000 (Direct Cost : ¥1,500,000)
Fiscal Year 1999 : ¥700,000 (Direct Cost : ¥700,000)
Fiscal Year 1998 : ¥800,000 (Direct Cost : ¥800,000)
The localization of apoptosis and apoptosis-related genes (p53, bcl-2) in non-melanoma skin cancers(squamous cell carcinoma(SCC, n=4), Bowen's disease(BD, n=5), actinic keratosis(AK, n=3), Basal cell carcinoma(BCC, n=5) was investigated using immunostaining and the TUNEL method. The resulting locations were compared with those of proliferative activities determined by PCNA immunostaining and the degree of morphological differentiation. Apoptotic cells were detected among the dyskeratotic cells of SCCs, the differentiated parts of BD and AK lesions and some tumor cells of BCC. On the contrary, PCNA was positive in many tumor cells of SCCs, BCCs and most tumor cells of BDs. In the lesions of AK, basal and suprabasal cells were positive with PCNA. There results indicate that apoptotic process is related to the differentiation of squamoproliferative tumors. P53-positive cells were observed in the proliferative portion of BD and AK lesions. In SCC, more tumor cells were p53-positive compared to only a few in BCC, although there are variations of the degree of p53 expression. These results suggest that in SCC, BD and AK p53 expression is related to the proliferation of tumor cells. In BCC p53 also might be involved in the development of tumor cells. There is no consistent correlation between PCNA and p53 expression. No bcl-2 expression was observed in most cases of SCC, BD, AK and adjacent normal epidermis, although weak bcl-2 expression was detected in the basal cells in one case of BD. In 4 of 5 cases of BCC the diffuse expression of bcl-2 was detected in the tumor cells. These results suggest that bcl-2 may play an important role of the development of BCC. I could not find any relationships between the expression of bcl-2, PCNA and apoptosis. Further studies are needed to elucidate the mechanisms of apoptosis in non-melanoma skin cancer.