Steroids inhibit tumor promoting agent induced Epstein-Barr virus early antigens in raji cells

✍ Scribed by Syam K. Sundar; Dharam V. Ablashi; Gary R. Armstrong; Mitchell Zipkin; Alberto Faggioni; Paul H. Levine

• Book ID: 102278546
• Publisher: John Wiley and Sons
• Year: 1981
• Tongue: French
• Weight: 471 KB
• Volume: 28
• Category: Article
• ISSN: 0020-7136
• DOI: 10.1002/ijc.2910280417

✦ Synopsis

Abstract

Four steroids and one protease inhibitor were evaluated for their effects on 12‐O‐tetradecanoyl phorbol 13‐acetate (TPA)‐induced and Epstein‐Barr virus‐induced early antigens (EBV‐EA) in Raji cells. Continuous treatment with dexamethasone, prednisolone, hydrocortisone and cortisone inhibited TPA‐induced EBV‐EA to varying degrees, but the protease inhibitor N‐α‐p‐tosyl L‐lysine chloromethyl ketone‐HCI (TLCK) had no significant effect. None of the agents tested inhibited EBV‐induced EA. In addition, the effect of the steroids was reversible since the removal of these agents resulted in recovery of the percentage of EBV‐EA‐positive cells in TPA‐treated cultures. These results were in agreement with the in vivo experiments of other investigators, who demonstrated inhibition of tumor promotion with steroids. Since TLCK failed to inhibit TPA‐induced EA, it is unlikely that induction of EA by TPA is the result of production of proteases.