How exercise might reduce prostate cancer progression

[JimJimJimJim]

Medscape Medical News, 1 February 2012[/i]']

HOW EXERCISE MIGHT REDUCE PROSTATE CANCER PROGRESSION

A new study suggests that vigorous physical activity will offer protection against prostate cancer progression because of its effects on DNA repair and cell-cycle pathways. These findings were highlighted during a presscast in advance of the 2012 Genitourinary Cancers Symposium (GUCS), held in San Francisco, CA. It was organized by the American Society of Clinical Oncology, one of the meeting’s sponsors.

Senior author June Chan, ScD, associate professor of epidemiology. biostatistics and urology at the University of California, San Francisco and colleagues, conducted a study in 70 men with low-risk prostate cancer who were undergoing active surveillance and who had been taking part in a study on nutritional supplements. The team looked at gene expression in biopsy specimens and found differences between the 23 men who reported exercising vigorously for at least 3 hours per week and the 47 men who reported less.

The men who exercised had a differential expression of 184 genes; the upregulated genes included well-known tumor suppressor genes such as BRCA1 and BRCA2, Dr. Chan reported. The gene-set analysis also revealed that cell-cycle and DNA repair pathways were positively modulated in men who reported participating in vigorous physical activity for at least 3 hours per week, compared with those who reported less, she added.

However, she noted, “there were no significant genes or pathways associated with the physical activity when we compared men reporting engaging in any vigorous physical activity [and those reporting engaging in] none, suggesting that a certain threshold of intensity or duration may be important.”

“These preliminary data suggest that DNA repair in the prostate gland is one mechanism through which vigorous physical activity may protect against prostate cancer progression,” Dr. Chan said. She emphasized that the study is small so the finding could be due to chance, and that potential confounding factors were not considered.

This study is just a hint.

Statistics tells us that small numbers mean small differences may be by chance.

The obvious confounding factor ignored was that men who exercise vigorously for more than 3 hours a week are often not like average men.

Many of them would also eat good foods, eschew poor foods, not smoke, drink little alcohol, and lead a generally moderate life.

So, the study may have just been mostly comparing the effect of a healthy lifestyle against a less healthy one.

If you are striving for a healthy lifestyle, this hint might give you some comfort.