March 15th, 2006

Habanera Hot Peppers

A study found that the capsaicin that is found in hot peppers caused prostate cancer cells to kill themselves. Researchers from the Samuel Oschin Comprehensive Cancer Institute at Cedars-Sinai Medical Center and UCLA published their results in today’s issue of Cancer Research.

The capsaicin is what makes our tongue burn when eating a jalapeños hot pepper. The researchers found that when they introduced the capsaicin to human prostate cancer cells it caused the cells to undergo a programmed cell death called apoptosis.

The researchers have studied the use of capsaicin on mice that had prostate cancer tumors. Their results were promising. There were approximately 80 percent of the prostate cancer cells that went through apoptosis. The prostate cancer mice that were treated with capsaicin had tumors that were one-fifth the size of the tumors compared to the mice that were not treated.

"Capsaicin had a profound anti-proliferative effect on human prostate cancer cells in culture," said Sören Lehmann, M.D., Ph.D. who is currently a visiting scientist at the Cedars-Sinai Medical Center and the UCLA School of Medicine. "It also dramatically slowed the development of prostate tumors formed by those human cell lines grown in mouse models."

The capsaicin pepper extract was fed to the mice orally. Lehmann estimates that it would be the equivalent of 400 milligrams of capsaicin three times a week for a man weighing 200 pounds. A man would have to eat 3 – 8 fresh habanera hot peppers which are the highest rated for capsaicin content. All hot peppers in the same variety can have varying amounts of capsaicin.

The scientists discovered the reason why the capsaicin worked. They found that the capsaicin disrupted the NF-kappa Beta which is a molecular mechanism which works in the pathways that lead to apoptosis in a variety of cell types.

"When we noticed that capsaicin affected NF-kappa Beta, that was an indication that we might expect some of the apoptotic proteins to be affected," said senior author, Phillip Koeffler, M.D., who is the director of Hematology and Oncology, Cedars-Sinai Medical Center, and professor at UCLA.

The researchers found the pepper extract was able to restrain the growth of prostate cancer cells by regulating androgen receptors. The capsaicin caused the prostate cancer cells to freeze by reducing the amount of testosterone entering the cell. Prostate cancer cells need testosterone to grow.

Prostate specific antigen (PSA) levels were lowered with capsaicin. The pepper extract also reduced the number of androgen receptors in the prostate tumor cells. The PSA blood test that is used on men is one of the early preliminary diagnostic tools used to warn of prostate cancer.