[Attachment of bacillus Calmette-Guerin to bladder cancer cells and the expression of interleukin-6 biological activity].

In order to elucidate the mechanisms of antitumor efforts of bacillus Calmette-Guerin (BCG), the effects of attachment of BCG to bladder carcinoma cell line EJ and the role of fibronectin in the in vitro experiment were studied. At the same time, the IL-6 biological activity in the medium of EJ cells was determined and the IL-6 biological activity in presence of BCG compared. The results indicated that BCG attached strongly to EJ cells, and the maximal attachment to the cells with BCG occurred 48 hours after culture. Fibronectin could significantly increase the attachment and not acclerate the proliferation of EJ cells. In the presence of fibronectin-conditioned medium, the maximal percentage of the tumor cells with attached BCG was 74.22%. Under this condition of experiment, there was IL-6 biological activity in the medium of EJ cells. The treatment of EJ cells with BCG did not regulate the expression of IL-6.