Abstract: The expressions of p53 protein, PCNA and macrophage count in 50 cases of skin squamous cell carcinoma were studied by LSAB immunostaining of monoclonal antibodies (PC-10, CD68 and Do-7). The relationship between the proliferation of cancer cell and the count of stroma macrophage to the degree of differentiation was studied and observed in situ. The results showed that the positive rates of expression of both p53 protein and PCNA in the squamous cell carcinoma were 56% and 100%, respectively. The distribution and strength of the expression of p53 protein and PCNA were positively correlated to the degree of cell differentiation. Macrophoge regularly located in the margin of cancer nest. The macrophage count was reversely correlated to the degree of differentiation. It is concluded that the degree of differentiation is parallel to the expression of p53 protein and PCNA, whereas, the macrophages in the stroma to some extent inhibits the cancer cell proliferation.

Key words: Carcinoma, squamous cell, Protein p53, PCNA, Macrophages