A NOVEL STYRYL DIPHENYLAMINE DERIVATIVE REVERTS THE TRANSFORMED PHENOTYPE OF HUMAN FIBROSARCOMA HT1080 CELLS

Revertant cells, which can be isolated from transformed cells, are fla t, non-transformed variants that have contributed to the elucidation o f mechanisms involved in cell transformation. We have discovered that a novel styryl diphenylamine derivative converts human fibrosarcoma HT 1080 cells into revertant cells. This compound induces Bat cell morpho logy and causes a decrease in proliferative rate. The Bat revertant ce lls not only exhibit a reduction in saturation density at confluence, but also lose the ability to proliferate in soft agar. Furthermore, th eir tumorigenicity is reduced when injected s.c. into athymic nude mic e. The compound alters morphology in three out of seven cancer cell li nes and has a potent growth inhibitory effect in six of these lines. I n contrast, it has only low levels of cytotoxicity for three normal di ploid cell lines. These findings indicate that this styryl diphenylami ne derivative has the potential to suppress the malignant phenotype of cancer cells without profound cytotoxicity in non-transformed cells.