Tuesday April 13 2:38 AM ET

Vitamins May Make Cancer Less Aggressive

By Maggie Fox, Health and Science Correspondent

PHILADELPHIA (Reuters) - Vitamins may not prevent cancer but they could help make it less aggressive in patients at high risk of the disease, researchers said Monday.

Several studies presented at a meeting of the American Association for Cancer Research show that supplements -- ranging from ordinary multivitamins to specially formulated vegetable-based capsules -- may slow the course of cancer.

In one study, Dr. Omar Kucuk and colleagues at the Barbara Ann Karmanos Cancer Institute in Detroit found tomato supplements helped slow prostate cancer in men diagnosed with the disease.

The supplements, made by LycoRed Natural Products in Beersheva, Israel, contained lycopene, the chemical that makes tomatoes red.

Lycopene, which survives cooking and is especially concentrated in tomato sauce and tomato paste, is a known antioxidant and member of the carotenoid family of nutrients that include beta-carotene and vitamin A. It cancels out the effects of free radicals, which are charged particles that can roam the body and damage DNA, leading to cancer.

Kucuk's team studied 30 men aged 60 to 80 who had prostate cancer and were waiting to have surgery. Half received 30 mg of the supplements a day, and half received dummy pills.

Their tumors were then examined after surgery.

``The men who took lycopene had lower PSA levels in their tumors,'' Kucuk said, referring to the prostate-specific antigen that is produced by prostate cancer cells. PSA not only marks prostate cancer but can also predict its severity.

Kucuk said the tumors in men who took lycopene were also smaller.

``This shows that lycopene may not only be possibly preventive for prostate cancer but may possibly in the future play a role in treatment,'' Kucuk told a news conference.

The supplements may have been especially potent, Kucuk said, because they contained only tomato products. He added that other compounds in the tomatoes, in addition to lycopene, may also have acted on the tumors.

In a second study of 135 patients presented at the conference, Bruce Trock and colleagues at Georgetown University Medical Center in Washington, D.C., found that men who took vitamin supplements and later developed head and neck cancer experienced a less-aggressive form of the disease.

Trock said previous studies had shown 60 percent of men with head and neck cancers -- which affect heavy smokers and drinkers and especially African-American men -- have mutations in a gene called p53, which is known to help control the mechanisms that lead to cancer.

``Those patients who had been regular users of vitamin supplements prior to the development of disease had a three-fold reduction in the mutation of p53,'' Trock said.

When doctors checked to see which patients had taken known antioxidants, such as vitamins A, C and E, the effect was even stronger, with a four-fold reduction in the mutations.

These men were known to have unhealthy lifestyles. Although they had taken vitamins, they were also smokers, drinkers and did other things known to make a person prone to cancer, such as eating fatty food, few vegetables and avoiding exercise.

Yet no matter what aspect Trock's group looked at, it seemed the vitamins were the main factor in reducing the mutations.

Having fewer genetic mutations could translate into a milder version of cancer, Trock said. Other studies have shown that the more mutations there are in p53, the faster the cancer spreads and the less likely the patient is to survive.

``Regular vitamin use prior to development of disease may affect its aggression,'' Trock concluded.

``The vitamins didn't prevent these people from getting the disease, but they may have affected the biology of the tumor.''