High-dose vitamin C can boost the cancer-killing effect of chemotherapy in the lab and mice, research suggests. Given by injection, it could potentially be a safe, effective and low-cost treatment for ovarian and other cancers. US scientists ... call for large-scale government clinical trials. Vitamin C has long been used as an alternative therapy for cancer. In the 1970s, chemist Linus Pauling reported that vitamin C given intravenously was effective in treating cancer. However, clinical trials of vitamin C given by mouth failed to replicate the effect, and research was abandoned. It is now known that the human body quickly excretes vitamin C when it is taken by mouth. However, scientists at the University of Kansas say that when given by injection vitamin C is absorbed into the body, and can kill cancer cells without harming normal ones. The researchers injected vitamin C into human ovarian cancer cells in the lab, into mice, and into patients with advanced ovarian cancer. They found ovarian cancer cells were sensitive to vitamin C treatment, but normal cells were unharmed. The treatment worked in tandem with standard chemotherapy drugs to slow tumour growth. "Because vitamin C has no patent potential, its development will not be supported by pharmaceutical companies," said lead researcher Qi Chen. "We believe that the time has arrived for research agencies to vigorously support thoughtful and meticulous clinical trials with intravenous vitamin C."