Inositol-phosphate-induced enhancement of natural killer cell activity correlates with tumor suppression.
In recent studies, we have demonstrated that inositol hexaphosphate (InsP6) inhibits experimental colon carcinogenesis. Since natural killer (NK) cells are involved in tumor cell destruction, we investigated the effect of InsP6 on murine NK cell activity. We show that; (i) 1,2-dimethylhydrazine (DMH), a colon carcinogen, depresses NK activity; (ii) in vivo treatment of mice with InsP6 enhances baseline NK activity and reverses DMH-induced depressed NK activity with an inverse correlation (r = -0.9811) with tumor incidence, (iii) short-term in vitro treatment of spleen cells and NK-enriched fraction with InsP6 also enhances NK cytotoxicity in a dose-dependent manner, (iv) inositol potentiates the action of InsP6. Our data suggest yet another important role of inositol phosphates in the regulation of cellular activity.
University of Maryland School of Medicine, Baltimore, MD 21201.
A
A
Baten
A
A
Ullah
V J
VJ
Tomazic
A M
AM
Shamsuddin
D019813:1,2-Dimethylhydrazine; D000818:Animals; D002273:Carcinogens / Q000494:pharmacology*; D002478:Cells, Cultured; D003602:Cytotoxicity, Immunologic / Q000187:drug effects*; D004127:Dimethylhydrazines / Q000494:pharmacology*; D007694:Killer Cells, Natural / Q000187:drug effects / Q000276:immunology*; D008297:Male; D008763:Methylhydrazines / Q000494:pharmacology*; D051379:Mice; D008809:Mice, Inbred C3H; D009374:Neoplasms, Experimental / Q000473:pathology / Q000517:prevention & control; D010833:Phytic Acid / Q000494:pharmacology*; D012016:Reference Values; D013154:Spleen / Q000276:immunology
D002273:Carcinogens; D004127:Dimethylhydrazines; D008763:Methylhydrazines; D010833:Phytic Acid; D019813:1,2-Dimethylhydrazine