RNA polymerase activity in human brain tumors

Abstract

Inhibition of nuclear RNA polymerase activity by cycloheximide, rifampicin, and Mpha-am~nitin was studied in human brain tumors. Although Mpha-amanitin inhibited about 90~ of the total activity in half of these tumors, the other group showed significant RNA polymerase inhibition by rifampicin. This is an unusual result, and for clear interpretation will require additional study on isolated enzymes from animal brain tumor modcls having similar P~NA polymerase activity.