Evaluation of the anticancer activities of Tweens 20, 40 and 60 in SJL/J mice.

Tween 20 (polyoxyethylenesorbitan monolaurate), Tween 40 (polyoxyethylenesorbitan monopalmitate), and Tween 60 (polyoxyethylenesorbitan monostearate) were found to have little activity against development of reticulum cell sarcoma in SJL/J mice. These findings resulted in studies to explain the previous observation that Tween 80 (polyoxyethylenesorbitan monooleate) has anticancer activity in the SJL/J tumor system. Evidence is presented to suggest that the apparent difference may be related to the fatty acid component (saturated or unsaturated) of the Tween.