Working with the popular drugs Celebrex and Lipitor, researchers have demonstrated how the combination of these two drugs has halted the advance of prostate cancer from stage one into a more advanced, potentially lethal, stage of the disease.

Celebrex (celecoxib) is a nonsteroidal anti-inflammatory drug (NSAID) often prescribed for pain relief and Lipitor (atorvastatin) is a statin drug used to lower cholesterol levels.

More than 250,000 cases of prostate cancer are diagnosed in the United States every year.  It is the number two leading cause of cancer death in American men.

The research team, led by Professor Xi Zheng, of Rutgers University’s Ernest Mario School of Pharmacy, presented their work at the April 14 annual meeting of the American Association for Cancer Research in San Diego.

Traditional treatment for prostate cancer involves one of two anti-androgen therapeutic options:  decreasing the production of androgen hormones, including testosterone, or blocking the action of the androgens on the cancerous cells.  In its earliest stage, when diagnosis is typical, prostate cancer cells rely on androgen hormones to fuel their growth.

Anti-androgen therapy has proven to be effective in slowing the progression of the disease but cancer cells eventually grow to be independent of the influence of the androgens, which makes them more aggressive and the disease advances to a more dangerous stage, where treatment is not often successful.  Chemotherapy drugs are often used at this stage but they are highly toxic and not necessarily effective.

Looking for ways to delay the transition to the androgen-independent stage, Zheng and his colleagues first used cell cultures from four different cell lines to test their Celebrex-Lipitor drug combo theory.  When these studies proved successful, they advanced the testing phase to include specially bred laboratory mice with prostate cancer tumors.

The mice were divided into three study groups:  one receiving Celebrex only, one receiving Lipitor only, and one receiving a combination of the two.

The researchers discovered that even low doses of the combo produced greater results than high doses of either of the drugs alone.  They were able to significantly delay the progression of the cancer from the first, androgen-dependent, stage to the second, harder to treat, state.

The research team is now delving into the underlying molecular workings of the study to isolate exactly how the drug combo stalls the progression of the disease from one stage to the next.  In an earlier study using the Celebrex-Lipitor combo, researchers were able to slow the growth of late-stage, androgen-independent, prostate cancer cells.

Allan Conney, Rutger’s director of the Susan Lehman Cullman Laboratory for Cancer Research, remarks that if a form of treatment can be developed to affect the early stage of prostate cancer to keep it from progressing to the more dangerous stage, progress is good.  But if growth in the second stage can also be inhibited, that’s even better.  Conney is a member of Zheng’s research team.

Clinical trials using humans are in the planning stage at the New Brunswick Robert Wood Johnson Medical School, University of Medicine and Dentistry of New Jersey.  Conney hopes clinical trials go as planned, with an effective treatment regimen available in five years or less.