Predictive value of statin, a G0-associated cell cycle protein, in childhood acute lymphoblastic leukemia

Blast cells of 71 children with newly diagnosed acute lymphoblastic leukemia (ALL) were examined with a novel monoclonal antibody (MAb), S-44, immunoreactive to statin, a nuclear protein specifically expressed in non-proliferating cells. The statin labeling index (LI) varied greatly from case to case and ranged from 0.3% to 86%, with a mean value of 10%. The degree of statin LI correlated inversely with the expression of Ki-67. When patients were subdivided according to whether the statin LI was higher or lower than the mean value, patients with higher statin LI did not respond to chemotherapy and survived for a shorter period of time. Our results suggest that labeling of statin with the S-44 MAb is a useful prognostic marker of the cytotoxic effects of anti-cancer drugs in patients with ALL.