Biochemically, GcMAF results from sequential deglycosylation of the vitamin D-binding protein (the Gc protein), which is naturally promoted by lymphocytes (B and T cells). The resulting protein may be a macrophage activating factor (MAF). MAFs are lymphokines that control the expression of antigens on the surface of macrophages, and one of their functions is to make macrophages become cytotoxic to tumors.
False cancer-curing claims
Three out of four of the original studies authored by Yamamoto (published between 2007 and 2009) were retracted by the scientific journals in which they were published in 2014, officially due to irregularities in the way ethical approval was granted. Retraction reasons also included methodological errors in the studies. The integrity of the research, conducted by Nobuto Yamamoto and colleagues, that originally prompted claims regarding cancer and HIV has been questioned.
The UK Medicines and Healthcare products Regulatory Agency and Cancer Research UK has warned the public about spurious claims of clinical benefits, misleadingly based on reduced levels of the alpha-N-acetylgalactosaminidase enzyme (also known as nagalase), whose production might be increased in many cancers.
In 2015 the UK Medicines and Healthcare products Regulatory Agency (MHRA) closed a factory in Milton, Cambridgeshire owned by David Noakes' company Immuno Biotech manufacturing GcMAF for cancer treatment.
As of 2014 an Israeli company called Efranat was running a clinical trial of GcMAF in people with various kinds of cancer at a hospital in Israel. As of December 2017 Efranet had obtained an orphan designation from the FDA for use of GcMAF in recurrent respiratory papillomatosis and said that it was conducting a Phase I trial in Israel.
- Galactosidases — Advances in Research and Application. Scholarly Editions. 21 June 2013. p. 52. ISBN 978-1-4816-8801-7.
- "GCMAF". Anticancer Fund. 24 July 2014. Retrieved 2014-07-26.
- Malik, Suneil; Fu, Lei; Juras, David James; Karmali, Mohamed; Wong, Betty Y. L.; Gozdzik, Agnes; Cole, David E. C. (January–February 2013). "Common variants of the vitamin D binding protein gene and adverse health outcomes". Critical Reviews in Clinical Laboratory Sciences. 50 (1): 1–22. doi:10.3109/10408363.2012.750262. PMC . PMID 23427793.
- Mosser, David M. (February 2003). "The many faces of macrophage activation". Journal of Leukocyte Biology. 73 (2): 209–212. doi:10.1189/jlb.0602325. PMID 12554797.
- Arney, Kat (3 December 2008). "'Cancer cured for good?' – Gc-MAF and the miracle cure (revised 25 July 2014)". Cancer Research UK. Retrieved 10 February 2015.
- (Retracted) Yamamoto, Nobuto; Ushijima, Naofumi; Koga, Yoshihiko (January 2009). "Immunotherapy of HIV-infected patients with Gc protein-derived macrophage activating factor (GcMAF)". Journal of Medical Virology. 81 (1): 16–26. doi:10.1002/jmv.21376. PMID 19031451.
- Miller, Michael E. (16 July 2015). "The mysterious death of a doctor who peddled autism 'cures' to thousands". Washington Post. Retrieved 26 August 2015.
- "Press Release: Regulator warns against GcMAF made in unlicensed facility in Cambridgeshire - GOV.UK". Medicines and Healthcare products Regulatory Agency. 3 February 2015.
- (Retracted) Yamamoto, Nobuto; Suyama, Hirofumi; Yamamoto, Nobuyuki; Ushijima, Naofumi (15 January 2008). "Immunotherapy of metastatic breast cancer patients with vitamin D-binding protein-derived macrophage activating factor (GcMAF)". International Journal of Cancer. 122 (2): 461–467. doi:10.1002/ijc.23107.
- Yamamoto, N.; Suyama, H.; Nakazato, H.; Yamamoto, N.; Koga, Y. (2014). "Retraction Note to: Immunotherapy of metastatic colorectal cancer with vitamin D-binding protein-derived macrophage-activating factor, GcMAF". Cancer Immunology, Immunotherapy. 63 (12): 1349. doi:10.1007/s00262-014-1616-x.
- "Retraction". International Journal of Cancer. 135 (6): 1509. 15 September 2014. doi:10.1002/ijc.29014.
- Ivan Oransky (25 July 2014). "Paper about widely touted but unapproved "cure" for cancer, autism retracted". Retractionwatch.
- "Tracking retractions as a window into the scientific process Yet another study of widely touted cancer "cure" retracted". Retraction Watch. Retraction Watch. Retrieved 28 July 2015.
- UK's MHRA shuts down GcMAF plant (FDA News website)
- Cancer treatment developer Efranat raises $4.5 million, November 18, 2014 (Globes)
- "Orphan Drug Designation - Modified vitamin D binding protein". FDA. Retrieved 13 December 2017.
- "Vitamin D binding protein macrophage-activating factor". AdisInsight. Retrieved 7 September 2017.