Expression of lactate and malate dehydrogenases in tumors induced by SV40 and 7,12-dimethylbenz(a)anthracene.

Isozyme patterns of lactate and malate dehydrogenases were studied in tumors induced by SV40 and 7,12-dimethylbenz(a)anthracene and in established cultures of cells from these tumors. The expression of B polypeptide subunits of lactate dehydrogenase is suppressed similarly by both agents. This may be due to inactivation of the gene at the locus determining the B polypeptide subunit. Malate dehydrogenase isozyme patterns are not changed significantly by the virus or the carcinogen.