Calyculin A, a non-phorbol ester type tumor promotor, induced oxidative DNA damage in stimulated human neutrophil-like cells.

Calyculin A(CA) induced 8-hydroxydeoxyguanosine (8OHdG), typical of mutagenic oxidative DNA damage, in N-Formyl-Methionyl-Leucyl-Phenylalanine (FMLP)-stimulated dimethyl sulfoxide(DMSO)-differentiated HL60(DMSO-HL60), which has characteristics similar to those of human neutrophils. CA enhanced O2-generation in FMLP-stimulated DMSO-HL60. CA by itself neither induced 8OHdG nor O2-generation. FMLP by itself induced O2-generation, however, it did not induce 8OHdG. These findings suggest that CA exerts its tumor promotion activity through modulating O2-generation and through inducing oxidative DNA damage and that a common bioactive peptide induces oxidative DNA damage under a certain condition.