Insulin potentiation therapy

# Overview
Insulin potentiation therapy ("IPT") is a controversial alternative medicine therapy that uses Food and Drug Administration-approved cancer fighting drugs in lower doses. It is used by some alternative medicine practitioners to treat cancer and other diseases because the lower dosing of drug eliminates many of the debilitating side effects of conventional chemotherapy. This treatment is also sometimes referred to as "low dose chemotherapy."

# Proposed mechanism
Based on a body of scientific evidence (see refereneces), IPT practitioners and proponents have put forth that insulin modifies cancer cells' receptivity to penetration by chemotherapy drugs. It is well known that the hormone insulin, which is created in the pancreas, modulates many of the body's functions at the cellular level and the regulation of blood glucose levels is the best-known example.
Cancer cells secrete their own insulin and insulin-like growth factor (IGF) which work together to consume a body's nutrients to grow cancer. Cancer cell membranes have about sixteen times more insulin and IGF receptors than normal cells and these receptors react with natural or administered insulin. When insulin is administered, the cancer starves for glucose and generates enzyme activity that makes the cell membrane more permeable to chemotherapy drugs. By using the very same mechanisms that cancer cells use to grow and kill people, IPT channels more of the chemotherapy drug into the cancer cells, killing them and leaving normal cells less affected.
Side effects that normally accompany chemotherapy are minimized because the chemotherapy doses can be as little as 10-15% of the standard dose.
The principal proponent of this procedure is Dr. Donato Perez Garcia (1958-), grandson of the discoverer, Dr. Donato Perez Garcia (1896-1971), who claims that IPT is especially effective with breast cancer.  He suggests that it is also effective with a number of other cancers, including small-cell lung cancer and prostate cancer.  Essentially, if a cancer can be significantly affected by existing chemotherapy drugs, then insulin potentiation therapy may be effective, without major side effects.  Steven G. Ayre, MD opened the first clinic in the US providing IPT in November 1999 called  Contemporary Medicine.
The original website about IPT is IPTQ.com, run by Chris Duffield Ph.D., a visiting researcher at Stanford University.  For an up to date directory of IPT certified practitioners worldwide, go to IPT for Cancer.

# Supportative research
Several in-vitro studies (test-tube) have shown how IPT works supporting the informal clinical work that has been conducted on hundreds of patients worldwide.
The first clinical trial of IPT for treating breast cancer was done in Uruguay and published in 2003/2004.  Insulin combined with low-dose methotrexate (a chemotherapy drug) resulted in greatly increased stable disease, and much reduced progressive disease, compared with insulin or low-dose methotrexate alone.
In 2000, the National Cancer Institute's Cancer Advisory Panel on Complementary and Alternative Medicine (CAPCAM) invited Drs. Perez Garcia and Ayre to present IPT to them as part of the National Cancer Institute's (NCI's) Best Case Series program.  The Elka Best Foundation is working to support research and education in this area.  The proponents of IPT claim to eliminate side effects of chemotherapy for at least some patients.

# Footnotes
-  Alabaster O, Vonderhaar B, Shafie S (1981). "Metabolic modification by insulin enhances methotrexate cytotoxicity in MCF-7 human breast cancer cells". Eur J Cancer Clin Oncol. 17 (11): 12238. PMID 7037424.CS1 maint: Multiple names: authors list (link) .mw-parser-output cite.citation{font-style:inherit}.mw-parser-output q{quotes:"\"""\"""'""'"}.mw-parser-output code.cs1-code{color:inherit;background:inherit;border:inherit;padding:inherit}.mw-parser-output .cs1-lock-free a{background:url("")no-repeat;background-position:right .1em center}.mw-parser-output .cs1-lock-limited a,.mw-parser-output .cs1-lock-registration a{background:url("")no-repeat;background-position:right .1em center}.mw-parser-output .cs1-lock-subscription a{background:url("")no-repeat;background-position:right .1em center}.mw-parser-output .cs1-subscription,.mw-parser-output .cs1-registration{color:#555}.mw-parser-output .cs1-subscription span,.mw-parser-output .cs1-registration span{border-bottom:1px dotted;cursor:help}.mw-parser-output .cs1-hidden-error{display:none;font-size:100%}.mw-parser-output .cs1-visible-error{display:none;font-size:100%}.mw-parser-output .cs1-subscription,.mw-parser-output .cs1-registration,.mw-parser-output .cs1-format{font-size:95%}.mw-parser-output .cs1-kern-left,.mw-parser-output .cs1-kern-wl-left{padding-left:0.2em}.mw-parser-output .cs1-kern-right,.mw-parser-output .cs1-kern-wl-right{padding-right:0.2em}
-  Witt K, Huber J, Egleton R, Davis T (2000). "Insulin enhancement of opioid peptide transport across the blood-brain barrier and assessment of analgesic effect". J Pharmacol Exp Ther. 295 (3): 9728. PMID 11082431.CS1 maint: Multiple names: authors list (link)
-  Lasalvia-Prisco E, Cucchi S, Vazquez J, Lasalvia-Galante E, Golomar W, Gordon W (2004). "Insulin-induced enhancement of antitumoral response to methotrexate in breast cancer patients". Cancer Chemother Pharmacol. 53 (3): 2204. PMID 14655024.CS1 maint: Multiple names: authors list (link)