Data against vit C cancer therapy flawed?

A recent study, which concluded that high doses of vitamin C reduce the effectiveness of chemotherapeutic drugs in the treatment of cancer was  seriously flawed, according to an article that was published in the  journal Alternative and Complementary Therapies.

The article challenges the findings of a study published in the journal  Cancer Research, in which the authors conclude that vitamin C given to  mice or cultured cells treated with common anticancer drugs reduces the  antitumor effects of the chemotherapeutic agents.

It highlights two main problems with the study: the oxidized form of  vitamin C (dehydroascorbic acid) was utilized, a compound that is not  used as a dietary supplement in humans; and in the mouse experiments,  the animals were given toxic dose levels.