[Expression of MUC1 and distribution of tumor-infiltrating dentritic cells in human bladder transitional cell carcinoma].

OBJECTIVE

To study MUC1 expression and distribution of tumor-infiltrating dentritic cells (TIDCs) in human bladder transitional cell carcinoma (BTCC).

METHODS

Immunohistochemical staining was employed to detect MUC1 expression and TIDC distribution in 69 surgical specimens of BTCC. MUC1 expression was also detected immunohistochemically in BIU-87, T-24 and drug-resistant BIU87/A cells. Flow cytometry was performed for determining the apoptosis rates of these 3 cells after a 48-hour treatment with adriamycin, vincristine and cisplatin, respectively.

RESULTS

MUC1 expression was detected in the BTCC tissues of all stages and the immunohistochemical staining patterns were significantly associated with the pathological grade and clinical stage of the tumors (P<0.001). The number of TIDCs in the tumors was inversely correlated with tumor pathological grades and clinical stages (P<0.005). MUC1 expressed weakly in the cytoplasm and on the membrane of BIU-87 cells and T-24 cells, but strongly in the cytoplasm and membrane of BIU-87/A cells, showing significant differences between the drug-sensitive and -resistant cells (P<0.05). The apoptosis rates of BIU-87 cells and T-24 cells increased obviously after treatment with adriamycin, vincristine and cisplatin, but no significant differences were noted between the two cells or between the 3 drugs. The apoptosis rate of BIU87/A cells, however, exhibited no obvious increase after adriamycin or vincristine treatment, but showed significant increase in response to cisplatin treatment (P<0.05).

CONCLUSIONS

The expression pattern of MUC1 and distribution of TIDCs can be useful markers to evaluate the degree of malignancy and prognosis of BTCC. The decrease in the number of TIDCs may have important relation to tumor immune evasion and immune tolerance, and MUC1 over-expression may lead to drug resistance of BTCC, indicating its involvement in tumor infiltration and metastasis.