[The relationship between the production of interleukin-6 and the proliferating cell nuclear antigen (PCNA) expression in renal cell carcinoma].

The relationship between the proliferating cell nuclear antigen (PCNA) expression in renal cell carcinoma (RCC) determined by immunohistochemical staining using the PC10 clone, and the preoperative serum interleukin-6 (IL-6) value determined by ELISA was examined. The secretion of IL-6 in RCC was also examined immunohistochemically using an anti-IL-6 antibody. The PCNA labeling rate was significantly higher in grade 3 tumors than in grade 1 tumors (p < 0.05), but there were no significant differences between the other grades or TNM stages. No significant correlation was obtained between the serum level of IL-6 or the positive cell rate of IL-6 and the pathological grade of the RCC. A correlation was observed between the PCNA labeling rate and positive cell rate, and between the serum IL-6 value and CRP or ESR. In conclusion, the secretion of IL-6 was detected in RCC tissue, and was suggested to be a tumor factor responsible for the growth and spread of RCC. The serum IL-6 value is considered to reflect the total secretion of IL-6 produced by the RCC and accessory cells, i.e., monocyte-macrophage lineage cells, endothelial cells and fibroblasts.