Scientists at the University of Otago's School of Medicine in New Zealand say they have uncovered the first real evidence of a connection between vitamin C and reduced tumour growth, news which will be welcomed by the international fresh produce trade.
Writing in the Cancer Research Journal, the group said it had found that vitamin C slowed the growth of tumour cells and made them more responsive to chemotherapy.
The study, led by Associate Professor Margreet Vissers of the University’s Free Radical Research Group, could lead to fresh fruits high in the vitamin being officially sanctioned as effective means to prevent and treat cancer.
Professor Vissers commented: 'Our results offer a promising and simple intervention to help in our fight against cancer, at the level of both prevention and cure.'
The role of vitamin C in cancer treatment has been the subject of debate for years, but so far accounts of the beneficial role of vitamin C in both the prevention and treatment of cancer have been purely anecdotal.
Previous research by Professor Vissers demonstrated the vitamin’s importance in maintaining cell health, but only hinted at its potential for limiting diseases such as cancer.
The new study investigated whether the cancer cells in the wombs of female patients had low vitamin C levels and whether this correlated with tumour aggressiveness and resistance to chemotherapy.
Professor Vissers and her colleagues found that the tumours were less able to accumulate vitamin C compared with normal healthy tissue, and that this related to the ability of the tumour to survive and grow.
Tumours with low vitamin C levels had more of a protein called HIF-1, which allows them to thrive in conditions of stress.
'The findings are significant as they show, for the first time, a direct relationship between HIF-1 and vitamin C levels in tumours and suggest it would be beneficial for people with cancer cells to have more vitamin C,' Professor Vissers commented.
'This could help limit the rate of tumour growth, increase the responsiveness to chemotherapy and may prevent the formation of solid tumours,' she added.
The results of the study, which was funded by the University of Otago and the Tertiary Education Commission, have been welcomed by New Zealand-based kiwifruit marketer Zespri.
'This research and other studies that are underway support the recommendation that Zespri kiwifruit, consumed daily as part of a healthy diet, help to boost the body’s vitamin levels, protecting the body from multiple adverse cellular events, and help strengthen the body’s natural defences,' said a spokesperson for the group.
Kiwifruit are an exceptional source of Vitamin C, with a single kiwifruit said to provide the recommended daily intake of the compound.
'Weight for weight, Zespri kiwifruit provide almost twice the vitamin C of oranges,' the spokesperson added.
