Kinase inhibitors are drugs that have been approved by America's Food and Drug Administration (FDA) as a cancer therapy-and it seems they are even more effective when the patient fasts, say researchers led by Valter Longo at the University of Southern California.
The new approach seems to be effective against breast, colorectal and lung cancers because it interferes with the 'Warburg effect', so named after the German physician who discovered that cancer cells need excessive amounts of glucose (sugar) from food in order to proliferate.
If cancer cells are deprived of glucose through fasting, they turn to an emergency back-up source, an enzyme called a kinase, to continue their growth. This is where the kinase inhibitors come in, as they block the kinase pathways that can feed the cancer cells.
Fasting makes the kinase inhibitors more effective, says Longo. "Patients would have to use them for less time to achieve the same results. We anticipate that fasting will also reduce the toxicity of kinase inhibitors as it reduces that of chemotherapy to normal cells", said Prof Longo.
His theories about fasting as a cancer therapy are being tested in several clinical trials in Europe.
(Source: Oncotarget, published online, March 30, 2015)