UWC intensify anti-cancer study
25-year research into using chemical found in marine sponges continues
Some marine sponges – of which SA’s coastline is a treasure trove – were found many years ago to have anti-cancer properties.
However, they’re so toxic that administering them to patients would kill off healthy cells, not just the cancer cells.
Now, researchers at the University of the Western Cape – who are copying the structures of the molecules and producing them in the laboratory – are trying to figure out a delivery agent that will only target the cancer cells.
In doing so, they have collated a quarter of a century of research on this elusive sea family, latrunculid sponges, and have just had the paper published in the South African Journal of Science.
The name “latrunculid sponges” is from the word lantruculins which refers to the family of natural products and toxins that are produced.
The report’s lead author Prof Michael Davies-Coleman, who is dean of natural sciences at UWC, said: “Marine organisms can’t move around. Some, like urchins, have spines to protect them. Molluscs have shells, but the softer things in tidal pools, like sponges, don’t have a shell and cannot run away. They must defend themselves chemically, and it is just pure luck that there are pharmaceutical applications for the chemicals they produce.”
Co-author Edith Antunes, from UWC’s department of chemistry, adds: “They are in a crowded environment competing for food and trying not to be eaten.”
They thus produce compounds to protect themselves and these can be “stunning colours of red, green and blue”, she says, adding that they are essentially deterrents to other organisms who might feed on them.
But, says Davies-Coleman, it is important to note that this is not in and of itself a “cure for cancer. You can’t just swallow the sponge and say now everything is sorted.”
Antunes says: “These compounds are so toxic that they would also kill normal cells. Because they’re extremely toxic, we are working on a delivery agent that will only target cancer cells and we will see if that works out.”
For Davies-Coleman, the paper just published is “a story about 30 years of work on one group of sponges that included people from many different disciplines”.
They include pharmacologists, microbiologists, ecologists and ichthyologists.
Marine biodiscovery (or bioprospecting) is the search for new pharmaceuticals, and Davies-Coleman said although his team was not the only one doing it, it has been at it the longest in SA.
“We – and New Zealand – have a biodiversity of this particular group of sponges and it has opened up a whole new field of sponge taxonomy. It’s a whole group effort and these are the most studied sponges in Africa,” he says.
Antunes says they have started work on the sponges as far back as 1996, “and after that more papers were published. Since our lab did the majority of the work, we put it all together into one paper”.