The sea cucumber, a common marine invertebrate in Philippine coastal waters can be a valuable source for treating human cancer patients, scientists at the University of the Philippines in Los Baños' Institute of Chemistry claimed.

Prof. Aleli Gana and Dr. Florinia Merca in a paper published in the Philippine Agricultural Scientist said that a substance known as lectin from the brown cucumber's (Holothuria sp.) body wall and internal organ inhibits the growth of lung cancer cells.

The scientists extracted and purified the lectin described to be complete non-blood and of C-type.  The substance has high agglutinating activities and inhibits the growth of human cancer cells in vitro at a concentration of 50 micrograms per milliliter.

Lectins, which are found in microorganisms, plants and invertebrates, are proteins that bind specifically to sugars in the cell membrane.  These have been in use for blood typing and are potential drugs against the AIDS virus and cancer, the scientists explained.

A kilogram of sea cucumber can yield about 40 milligrams of lectin, and imported purified lectins can cost up to $25 per milligram, the scientists added.

The important research was monitored by the Philippine Council for Aquatic and Marine Research and Development of the Department of Science and Technology.