Coincident with inhibition of STAT3 activity, application of WP1066 for only 2 weeks in vivo resulted in a 50% decrease in tumour area accompanied by a similar reduction in proliferation as measured by Ki-67 staining, and a concomitant increase in tumour cell apoptosis as measured by activated caspase 3 immunostaining. This evidence concerns the gene CASP3 and neoplasm.