Slow induction of gelatinase B mRNA by acidic culture conditions in mouse metastatic melanoma cells.

Gelatinase B has been thought to be a key enzyme for degradation of extracellular matrix in tumour invasion and metastasis. In this study, we examined the effect of acidic culture medium (pH 5.9) on the expression of gelatinase B mRNA in mouse metastatic melanoma cell line (B16-F10). Using reverse transcription-polymerase chain reaction (RT-PCR) analysis, we found that gelatinase B was induced by the acidic culture medium at 24 h, and then gradually diminished to 72 h. By gelatin zymographic analysis, gelatinase B was first detected at 24 h, continued to increase and then reached a plateau at around 48 h. These results suggest that the induction of gelatinase B secretion by acidic culture medium occurs as a result of the gene expression.