Competition for host essential and nonessential fatty acids by Ehrlich ascites carcinoma in mice
Baker, N.; Sandborg, C.; Morris, D.; Ookhtens, M.
Cancer Research 37(7 Pt 1): 2218-2225
1977
ISSN/ISBN: 0008-5472 PMID: 861947 Document Number: 120291
Mobilization of essential and nonessential free fatty acids (FFA) in control and Ehrlich ascites carcinoma-bearing mice was studied under varying nutritional conditions. Competition between tumor and host tissues for circulating FFA and the relationship between FFA transport rates (from blood to tumor) and FFA turnover in tumor extracellular fluid were also studied. Traders, /min) of palmitate equalled those of linoleate and were the same in cancerous as in control mice. The total plasma FFA pool was replaced at a rate of .apprx. 1.3 .mu.Eq/min per mouse in all groups. Only 0.01 .mu.Eq/min was transferred from blood to a 7 ml tumor. The presence of a large, rapidly growing ascites tumor did not increase FFA mobilization. A nearly negligible fraction of the FFA turning over in the extracellular fluid of the tumor (0.5 .mu.Eq/min per 7 ml tumor) could have been derived from plasma FFA. The cancer, the largest organ in the body of these mice, was unstable to compete effectively with the host for plasma essential as well as nonessential FFA. Either the slow FFA transport from blood to tumor can support the net growth of the tumor and energy requirements or another source of tumor fatty acids exists.