Effect of mitoxantrone on DNA polymerase of Ehrlich ascites carcinoma cells.

AIM

To study the effect of mitoxantrone (Mit) on DNA polymerases of tumor cells.

METHODS

DNA polymerases of Ehrlich ascites carcinoma cells were isolated by phosphocellulose column chromatography. The effects of Mit on DNA polymerase alpha, beta, and gamma were detected by method of K Ono.

RESULTS

Mit inhibited DNA polymerase alpha, beta, and gamma, IC50 values were 11.9, 6.5, and 11.9 mumol.L-1, and Ki 1.86, 2.22, and 2.05 mumol.L-1, respectively. The inhibitory mode of Mit on DNA polymerase alpha, beta, and gamma was competitive.

CONCLUSION

Mit is a strong inhibitor on DNA polymerase alpha, beta, and gamma. The inhibitory mode was competition with respect to template DNA.