“…More recent studies with differentiating culture systems have revealed that at greatly elevated levels, TGF-/3s can influence biochemical markers of keratinization, but at these high levels, they inhibit rather than promote, K1, K10, and filaggrin expression (Ma~nsbridge and Hanawalt,..1988;Choi and Fuchs, 1990). At li|gh concentration, TGF-/~s also enhance expression of K6 (56 kD) and K16 (48 kD), keratins more commonly associated with suprabasal layers of epidermis undergoing (a) wound healing (Mansbridge and Knapp, 1987) and (b) hyperproliferation (Weiss et al, 1984;Stoler et al, 1988). Studies using floating epidermal cultures have shown that induction of K6 and K16 is accompanied by morphological changes typical of squamous cell carcinomas, including increased stratification, vacuolization, and coilocyte formation (Choi and Fuchs, 1990).…”