Inhibition of an endogenous growth‐related proteinase enhances the recovery of a negative growth regulator from cultured human cells.

The possibility that a growth-related proteinase may act by degrading a negative growth regulatory protein has been investigated. Proteinase inhibitors which inhibit the enzyme also enhance the accumulation of the growth regulator by human fibroblasts. The negative growth regulator shows a similar specificity of inhibition of cellular growth to inhibitors of the growth-related proteinase.