Detection of interleukin (IL)-1 activity was studied in two human blad
der cancer cell lines, T24 and EJ1, and one rat bladder carcinoma cell
line, 804G. Significantly high proliferation of mouse thymocytes in t
he assay of IL-1 activity was observed in the conditioned medium (CM)
of T24 cells, indicating that the cells released IL-1-like activity. E
nzyme-linked immunosorbent assay (ELISA) and Northern blot analysis sh
owed the presence of both IL-1 alpha and IL-1 beta in the CM of T24 ce
lls and expression of mRNAs of both cytokines in the cells. Interleuki
n-l activity in EJ1 cells, which produced a little activity, was induc
ed by E. coli lipopolysaccharide (LPS) while it was not induced in T24
by either LPS or other test substances. Conditioned medium of T24 inc
reased proliferation of both T24 and EJ1 in cell-growth assay. Further
investigation of the mode of action and role of cytokines, especially
those from tumor cells themselves, is necessary in relation to BCG or
photodynamic therapy.