title: Buffer Therapy for Cancer.
abstract: Oral administration of pH buffers can reduce the development of spontaneous and experimental metastases in mice, and has been proposed in clinical trials. Effectiveness of buffer therapy is likely to be affected by diet, which could contribute or interfere with the therapeutic alkalinizing effect. Little data on food pH buffering capacity was available. This study evaluated the pH and buffering capacity of different foods to guide prospective trials and test the effect of the same buffer (lysine) at two different ionization states. Food groups were derived from the Harvard Food Frequency Questionnaire. Foods were blended and pH titrated with acid from initial pH values until 4.0 to determine "buffering score", in mmol H+/pH unit. A "buffering score" was derived as the mEq H+consumed per serving size to lower from initial to a pH 4.0, the postprandial pH of the distal duodenum. To differentiate buffering effect from any metabolic byproduct effects, we compared the effects of oral lysine buffers prepared at either pH 10.0 or 8.4, which contain 2 and 1 free base amines, respectively. The effect of these on experimental metastases formation in mice following tail vein injection of PC-3M prostate cancer cells were monitored within vivobioluminescence. Carbohydrates and dairy products' buffering score varied between 0.5 and 19. Fruits and vegetables showed a low to zero buffering score. The score of meats varied between 6 and 22. Wine and juices had negative scores. Among supplements, sodium bicarbonate and Tums®had the highest buffering capacities, with scores of 11 and 20 per serving size, respectively. The "de-buffered" lysine had a less pronounced effect of prevention of metastases compared to lysine at pH 10. This study has demonstrated the anti-cancer effects of buffer therapy and suggests foods that can contribute to or compete with this approach to manage cancer.
authors.affiliation: Department of Cancer Imaging and Metabolism, H. Lee Moffitt Cancer Center & Research Institute, Tampa, FL 33612 ; Department of Molecular Medicine, Biotechnology M.S. Program, University of South Florida, Tampa, FL 33612.
authors.forename: Maria de Lourdes C
authors.initials: MD
authors.lastname: Ribeiro
authors.affiliation: Department of Cancer Imaging and Metabolism, H. Lee Moffitt Cancer Center & Research Institute, Tampa, FL 33612.
authors.forename: Ariosto S
authors.initials: AS
authors.lastname: Silva
authors.affiliation: Department of Cancer Imaging and Metabolism, H. Lee Moffitt Cancer Center & Research Institute, Tampa, FL 33612 ; Department of Cell Biology, Microbiology, and Molecular Biology, Cancer Biology Ph.D. Program, University of South Florida, Tampa, FL 33612.
authors.forename: Kate M
authors.initials: KM
authors.lastname: Bailey
authors.affiliation: Department of Epidemiology and Population Sciences Division, H. Lee Moffitt Cancer Center & Research Institute, Tampa, FL 33612.
authors.forename: Nagi B
authors.initials: NB
authors.lastname: Kumar
authors.affiliation: Department of Epidemiology and Population Sciences Division, H. Lee Moffitt Cancer Center & Research Institute, Tampa, FL 33612.
authors.forename: Thomas A
authors.initials: TA
authors.lastname: Sellers
authors.affiliation: Departent of Radiology, H. Lee Moffitt Cancer Center & Research Institute, Tampa, FL 33612.
authors.forename: Robert A
authors.initials: RA
authors.lastname: Gatenby
authors.affiliation: Department of Cancer Imaging and Metabolism, H. Lee Moffitt Cancer Center & Research Institute, Tampa, FL 33612.
authors.forename: Arig
authors.initials: A
authors.lastname: Ibrahim-Hashim
authors.affiliation: Department of Cancer Imaging and Metabolism, H. Lee Moffitt Cancer Center & Research Institute, Tampa, FL 33612 ; Departent of Radiology, H. Lee Moffitt Cancer Center & Research Institute, Tampa, FL 33612.
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Gillies
keywords: Food buffering capacity; acid-base; metastasis; pH; sodium bicarbonate