Medicinal properties in mahogany bark may hold colon cancer cure

U of So. Carolina cancer researcher Dr. Michael Wargovich is studying whether medicinal properties in the bark of mahogany trees may hold clues to understanding colon cancer.

An unexpected entry in a traditional medicine book from the Republic of Guinea has led a University of South Carolina cancer researcher to study whether medicinal properties in the bark of mahogany trees may hold clues to understanding colon cancer.

Funded by a $300,000, two-year grant from the National Cancer Institute, Dr. Michael Wargovich will examine mahogany -- and four other medicinal plants native to West Africa -- in a quest to discover novel, anti-inflammatory compounds that could prevent or treat colon cancer.

The study, the first of its kind, could be a major first step to other studies of medicinal plants and cancer. Specifically, Wargovich is looking at how native medicinal plants in West Africa, used traditionally for pain relief, fever and inflammation, interact to inhibit the growth of cancer tumors.

"The link between inflammation and cancer is not known," said Wargovich, who researches the link between non-steroidal, anti-inflammatory drugs (NSAIDS) and cancer.

NSAIDS appear to block the function of Cyclooxygenase-1 (COX-1) and cyclooxygenase-2 (COX-2) enzymes that are found at sites of inflammation, he said.

"Studies have shown that regular use of NSAIDS, such as Celebrex and Vioxx, may reduce the risk for several types of cancer, particularly colon cancer," said Wargovich, a USC School of Medicine pathology professor and researcher with the S.C. Cancer Center.

"Yet, recently we've learned that long-term use of these drugs can put patients at risk for health problems, such as heart attack, stroke and gastrointestinal bleeding," he said. "Some NSAIDS have been removed from the market."

The solution, Wargovich said, is to find these same anti-inflammatory properties in plants.

The USC cancer researcher virtually stumbled upon the concept of studying the medicinal properties of West African plants. While visiting the Republic of Guinea and meeting with some of the country's top health officials, he was given a book, "Pharmacopée Traditionale Guineenne," that highlighted about 60 of the country's different plants and their health properties. He found that about 15 plants had anti-inflammatory properties.

"This was such an unusual, unexpected find," he said. "Very few people probably have even seen this book. And, here I was, a scientist with an interest in how the inflammation process may be linked to cancer, and I find a listing of specific plants that I had not thought about studying before."

For his study, Wargovich will focus on extracts from five West African plants: the neem tree, baobab tree, Senegal mahogany, African basil and kinkirissi bush.

"We believe that these African botanicals will have NSAID-like effects and will inhibit the COX pathways involved in cancer but will have a wider margin of safety," he said.

Wargovich is working with Clemson University researcher Dr. Feng Chen, whose expertise is in the chemistry of natural products. Chen is looking for the compounds in the mahogany bark that may be responsible for inhibiting inflammation.

"Our goal is to find the active inhibitors in African medicinal plants, used by traditional healers for centuries, that prevent disease," said Wargovich.

West Africa has a low incidence of colon cancer, and the reason why may be in the natural plants used by traditional healers. "Who would have thought that the mahogany tree could be the next Vioxx or Celebrex?" Wargovich said.