Buffer Therapy → Buffer Diet

Abstract

Malignant tumors exhibit an increase in glucose metabolism when compared to normal tissue. The increased metabolism generates an acidic tumor environment, which promotes local invasion, metastasis, and inhibition of immune surveillance. Oral buffers, e.g. 200 mM ad lib NaHCO3, can neutralize tumor acidity and prevent metastasis and improve immune therapy. Because of these promising results in preclinical cancers, phase I/ II clinical trials were initiated in cancer patients for either amelioration of pain or treatment of pancreatic cancer (GemTABS). In these two trials, NaHCO3 was provided in powdered form under an IND. However, compliance remains poor due to adverse effects including, but not limited to, diarrhea, vomitus, limb edema, and taste. Because of these challenges with buffer therapy in the clinic, we have investigated whether dietary manipulations could achieve the same effect by determining the buffering power of foodstuffs and supplements. From these data we generated a point system, wherein 1 point is equivalent to 1 g NaHCO3. Through endpoint titrations, we developed an analytical formula to relate points to food or supplement protein content (11 points per 100 g protein). Other buffers were more palatable compared to NaHCO3 and showed significant promise for dietary interventions. Hence we propose a mixed food + supplement diet can achieve a similar buffer load to that achieved with NaHCO3 alone.