EXPRESSION AND SIGNIFICANCE OF TUMOR INFILTRATING DENDRITIC CELLS IN RENAL CELL CARCINOMA

Objective: To study the expression of dendritic cells in human renal cell carcinoma and explore the cause, so to reveal the mechanism of escaping immune surveillance in RCC. Methods: The expressions of CD83+DCS, CD1a+DCS,VEGF and TGF-β1 in tumoral, peritumoral and normal kidney tissues of RCC in 30 cases were detected by immunohistochemistry using streptavidin/peroxidese(SP) Results: CD83+DCS were mainly located in the peritumoral areas; whereas CD1a+DCS、were mainly retained within the cancer nests. The number of CD83+DCS was inversely correlated with the clinical stage(P<0.05); but there were no significant correlations between the number of CD1a+DCS、and the clinical stage(P>0.05). The expressions of CD83+DCS and CD1a+DCS have significant difference between the tumoral, peritumoral and normal kidney tissues(P<0.001). The expression of VEGF and TGF-β1 were significantly lower in samples with highly infiltrating CD83+DCS(P<0.05); Whereas CD1a+DCS were not (P>0.05). Conclusion: DC has the tendency to gathering in tumor, but because of the immunosuppressive cytokins, for example VEGF and TGF-β1, inhibits the maturation of DC, there are less mature TIDCS(CD83+TIDCS) in the tumoral tissues, they are mainly located in the peritumoral areas. This may contribute to the mechanism of escaping immune surveillance in RCC.

Morphological observation of tumor infiltrating immunocytes in human rectal cancer

AIM： To investigate the morphological characterization of tumor infiltrating dendritic cells （TIDCs） and tumor infiltrating lymphocytes （TILs） in human rectal cancer. METHODS： Light and electron microscopy as well as immunohistochemistry were used to observe the distributive and morphological changes of TIDCs and TILs. RESULTS： TIDCs were mainly located in tumor-surrounding tissue. The number of TIDCs in the earlier stage was higher than that in the later stage （P〈 0.01）. TILs were mainly seen in adjacent tissue of cancers and tumor-surrounding tissue. There were more TILs in the earlier stage than that in the later stage （P〈0.01）. Under electron microscope, TIDCs were irregular in shape and exhibited many dendritic protrusions. It isn＇t obvious that cancer cells perforated the basement membrane and TILs were arranged along the basement membrane in the earlier stage. In the later stage, it is explicit that cancer cells perforated the basement membrane and surrounded by TILs. There were contacts among TIDCs, TILs and tumor cell. One IIDCs contacted one or several TILs which clustered around TIDCs. Glycogen granules were seen between TIDCs and Tits. CONCLUSION： The number of TIDCs and TILs is related with tumor progression There exist close relationships among TIDCs, TILs and tumor cell.