Controlled Amino Acid Therapy (CAAT) is a protocol developed for cancer patients that includes strict dietary guidelines and nutritional supplements focused on controlling amino acid and carbohydrate intake.1.2
The protocol was developed by the AP John Institute for Cancer Research and is believed to be based on extensive clinical research, but studies in humans or in animal models of the entire CAAT protocol have not been published. nor the results – case studies or observational studies – of the institute has been published. The exact protocol is not communicated and the institute’s website is no longer functioning.
Protocol components, such as selective amino acid restriction and supplements such as vitamin D and antioxidants, have been studied separately in vitro and in some animal models. This fact sheet focuses on the amino acid deprivation component.
Selective amino acid deprivation
A major component of CAAT is Selective Amino Acid Restriction Therapy (SAART), which is based on the assumption that many cancer cells develop mutations that prevent the synthesis of certain amino acids necessary for protein synthesis and therefore for protein synthesis. continued cell survival. When these cancer cells are deprived of an exogenous source of these amino acids, the cell cannot perform protein synthesis and therefore is unable to survive.3
It has been suggested that temporary selective amino acid deprivation can lead to cancer cell death without affecting normal cells or causing muscle proteolysis. This hypothesis, however, has not been fully tested in vivo, but is based on observations from studies of single amino acid deprivation and overall protein restriction in vitro and in vivo.
Study results suggest that a substantial decrease in overall protein intake inhibits cell proliferation in castration-resistant prostate cancer cells and that amino acid deprivation culture conditions (ie. EGFR-expression of cancer cell lines.4.5
Decreased protein intake also inhibited tumor growth, but did not affect body weight, in a human breast cancer xenograft mouse model.4 Several studies also suggest that selective amino acid deprivation of serine and glycine or phenylalanine and tyrosine may inhibit tumor growth in animal models.6.7
Numerous websites claim that CAAT has been studied in clinical trials. These trials, however, only evaluated the amino acid deprivation portion of the protocol and only in very small single-arm studies. A study in the 1960s, for example, evaluated 5 patients with metastatic melanoma who consumed a diet restricted in phenylalanine and tyrosine.8 Tumor growth was measured by calipers and lung metastases were monitored by x-ray. Four of the patients presented with slow tumor growth, which was also correlated with lower serum phenylalanine and tyrosine levels. The authors concluded that the diet appeared to inhibit tumor growth, but was difficult for patients to follow.