When exposed to cigarette smoke, normal breast cells lose their ability of repairing their damaged DNA

Aug 30, 2006 10:00 GMT  ·  By

A recent study carried out by researchers at the University of Florida found that besides other severe negative effects upon our health, smoking also increases the risk of breast cancer. In the case of women who have already been diagnosed with breast cancer, smoking works by worsening the symptoms of the serious condition.

University of Florida experts found in lab trials that normal breast cells exposed to cigarette smoke condensate lose their ability to repair their damaged DNA and develop abnormalities and mutations characteristic to cancer cells. The cigarette smoke condensate used by researchers was a tar produced by a machine that artificially "smokes" a cigarette. The tar contained all the 4000 chemicals which are found in tobacco smoke.

Tests showed that when normal, healthy breast cells were exposed to cigarette smoke condensate, the chemicals in tar activated a particular molecular gene. The gene in breast epithelial cells is known to activate a certain key-enzyme which repairs the damaged DNA in a cell.

"A defect in only one cell is important for growth of a full-blown tumor. You don't need 1 000 or one million cells to be affected. Only a single cell which may have genomic instability due to compromised DNA repair capacity of the cell can be sufficient for a tumor to develop," explained researcher Satya Narayan, Associate Professor of Anatomy and Cell Biology at University of Florida's College of Medicine.

Breast cancer is the most common type of cancer among women worldwide and the second leading cancer type to cause death, topped only by lung cancer. Surveys show that 1 in 7 women nowadays suffer from breast cancer. The incidence of breast cancer increases with age, risks of developing a malignant breast tumor rising dramatically in people over 50 years of age.

However, scientists highlight the fact that breast cancer does not affect only women. Men should be careful, too, because statistics show that for every 100 women who are breast cancer patients 1 male is very likely to develop the severe condition, too.