Vitamin C reduce effect of cancer drugs
London, Oct 1: Large doses of vitamin C supplements may substantially reduce the effectiveness of cancer drugs, a new research suggests. The Memorial Sloan-Kettering Cancer Center findings have been reported by Cancer Research.
To reach the conclusion, the US research team tested the impact of a form of vitamin C on the effectiveness of a range of anti-cancer drugs in tests on cancer cells in the lab. The analysis revealed that every drug they tested did not work as well if cells were pretreated with vitamin C as they did on untreated cancer cells. Between 30 pc and 70 pc less cancer cells treated with vitamin C were killed, depending on the drug tested.
Follow-up tests on mice showed that while chemotherapy kept untreated cancer in check, tumours grew more rapidly in mice that were given cancer pretreated with vitamin C.
Some classes of cancer drugs produce molecules known as oxygen free radicals which can react with other molecules in the cancer cell, forcing its death.
In
theory,
vitamin
C
could
mop
up
the
free
radicals,
keeping
the
cancer
cell
alive
despite
chemotherapy
treatment.
However,
the
researchers
found
the
key
was
not
that
the
nutrient
was
neutralising
free
radicals.
Instead, vitamin C appeared to protect tiny structures inside the cancer cells called mitochondria from damage. Mitochondria effectively form the energy-creating boiler room of a cell, and if damaged can lead to its death.
"Vitamin C appears to protect the mitochondria from extensive damage, thus saving the cell. And whether directly or not, all anti-cancer drugs work to disrupt the mitochondria to push cell death," BBC quoted lead researcher Dr Mark Heaney, as saying.
ANI