Distribution and expression profiles of dendritic cell subpopulations in human bladder cancer

Bladder cancer is one of the most common cancers worldwide, with transitional cell carcinoma (TCC) being the predominant form. Dendritic cells (DCs) are a heterogeneous population of antigen-presenting cells that play a crucial role in the regulation of the immune response and immunological tolerance. The aim of this study was to investigate the expression and characteristic of different DC subsets in non-muscle-invasive TCC (NMI-TCC), muscle-invasive TCC (MI-TCC) and controls. Our study demonstrated that normal human bladder contained only immature CD1a+, CD11c+, and CD209+ DCs whereas CD123+ pDCs and CD83+ mature DCs were virtually absent. The number of both CD11c+ IL-23+ mDCs and CD123+ pDCs were significantly elevated in NMIand MI-TCC, and the mDC populations of CD1a+, CD209+ immature DCs and CD83+ mature DCs also increased in NMIand MI-TCC. Except for a relatively low number of CD83+ mature DCs, the numbers of CD11c+, CD123+, CD1a+, CD209+ DCs were also significantly increased in MI-TCC compared with NMI-TCC. Taken together these results suggest that an imbalance in the distribution of tumor infiltrating DCs in the tumor area seems to be involved in the development or progression of bladder cancer.