SYNTEX RESEARCH DIVISION OF SYNTEX CORPORATION, STANFORD INDUSTRIAL PARK, PALO ALTO, CALIFORNIA 94304.

May 3, 1971

Dr. Joshua Lederberg RH-699
Department of Genetics

Schpol .of Medicine

Stanford University

Stanford, California 94305

Dear Dr. Lederberg:

I enjoyed reading your column prepared for "Science & Man"
(s226) and apologize for the delay in answering your re-
quest.

The literature certainly points out a correlation between
Suppression of the jmmune mechanisms and the incidence of
Cancer. However, as Sst 1 can determine, this relation-
ship is limited to use of the antimetabolites and is not a
concern of the corticosteroids. As a matter of fact, corti-
coids have been used therapeutically with, unfortunately,
little or no success. On the other hand use of these ster-

oids has not resulted in stimulation of neoplastic growth.

Although this does not speak directly to your question of
long-term carcinogenic potential of systemic corticoids, it

is as close as I can come. I hope this information is help-
ful.

Best regards.
Sincerely,

Redo 190 sous,

Robert Hill, Ph.D.
Director of Toxicology