Stearic acid and carcinogenesis.

Na Habib,M Aslam,Cb Wood,B Fermor,K Apostolov,W Barker,We Jenkins,Mj Hershman,D Heinemann,Rcn Williamson

doi:10.1038/bjc.1987.223

Abstract

Decreased membrane rigidity is one of the characteristics of malignant cells, resulting in part from the desaturation of stearic acid into oleic acid. In this study we investigated the influence of stearic acid on tumour cell inhibition in vitro and tumour development in vivo. Stearic acid inhibited the colony-forming ability of 4 out of 5 rat and two human tumour continuous cell lines in vitro. In contrast, the colony-forming ability of rat fibroblasts was not inhibited and that of human foetal lung fibroblasts was inhibited at a higher dose than that required to inhibit human tumour cell lines. Using a model of rat mammary carcinoma induced by nitroso-methyl urea (NMU) the subcutaneous injection of stearic acid at weekly intervals prevented tumour development in 5 to 10 rats. Using iodostearic acid twice weekly, 11 of 19 rats were alive and tumour free at week 22 whilst all of 14 animals injected with NMU alone had died of tumour by the 16th week. The ratio of stearic to oleic acids in erythrocyte membranes was significantly reduced in the tumour-bearing rats, but was normal in tumour-free animals treated with stearic or iodostearic acid. These preliminary data indicate that stearic acid inhibits tumour development in rats.

Highlights

We have noted previously that interferon inhibits the desaturation of stearic acid in vitro (Apostolov & Barker, 1981) and that interferon treatment of patients with hairy cell leukaemia leads to improvement in the saturation index in proliferative blood cells (Worman et al, 1987)
It has been suggested that one of the biological activities of interferon could be the inhibitory effect on delta 9 desaturase and subsequent increase in stearic acid and membrane rigidity (Apostolov & Barker, 1981)
These findings prompted the study of the possible use of exogenous stearic acid to prevent or reverse the desaturation of cell membrane stearic acid and thereby inhibit cell division both in vitro and in vivo

Summary

Introduction

We have noted previously that interferon inhibits the desaturation of stearic acid in vitro (Apostolov & Barker, 1981) and that interferon treatment of patients with hairy cell leukaemia leads to improvement in the saturation index in proliferative blood cells (Worman et al, 1987). It has been suggested that one of the biological activities of interferon could be the inhibitory effect on delta 9 desaturase and subsequent increase in stearic acid and membrane rigidity (Apostolov & Barker, 1981). These findings prompted the study of the possible use of exogenous stearic acid to prevent or reverse the desaturation of cell membrane stearic acid and thereby inhibit cell division both in vitro and in vivo

Methods

Results

Discussion

Conclusion