Compound isolated from sea sponge fights cancer cells

The ocean is home to powerful chemicals that may help treat cancer, researchers suggest. Photography by Dr. John Hooper

• Scientists believe novel chemicals with the potential to cure human illness may be found in the ocean.
• Researchers chemically synthesized a compound that had been isolated from a sea sponge.
• The compound — 3,10-dibromofascaplysin — was tested on various prostate cancer cells.
• The synthesized compound forces tumor cells to die.
• It works well in combination with several already approved anti-cancer drugs.

Much of the ocean remains unexplored, unknown to humans.

Increasingly, medical researchers are looking to this untapped resource in hopes of discovering novel marine chemicals that hold the potential to treat and cure human illness.

In 2019, the scientific world celebrated the 50th anniversary of the introduction of cytarabine, the very first marine-derived drug. Approved for the treatment of leukemia, the drug was isolated from a marine sponge.

As of October last year, nine drugs of marine origin had been clinically approved to treat cancer patients, according to Midwestern University.

Compound kills cancer cells

Now, researchers from Far Eastern Federal University (FEFU) in Russia, together with colleagues from elsewhere in Russia and Germany, have isolated the compound 3,10-dibromofascaplysin from the sea sponge Fascaplysinopsis reticulata and then chemically synthesized it.

They tested the substance on various prostate cancer cells, including those resistant to chemotherapy.

Their findings appear in the journal Marine Drugs.

Researchers found that 3,10-dibromofascaplysin forces tumor cells to die via a programmed cell death mechanism.

They also reported the synthesized compound works well in combination with several already approved anti-cancer drugs.

An intensively studied compound

Chemists first isolated the compound fascaplysin from a marine sponge in 1988. Today, it is known to possess antifungal, antibacterial, antiviral, antimalarial, and anti-tumor effects.

In 2017, FEFU researchers published a paper showing that fascaplysin derivatives kill glioblastoma multiforme cells — an aggressive type of brain cancer with a poor outlook for patients.

In 2019, several of those same FEFU researchers who published this study released research about their development of a new method to synthesize derivatives of fascaplysin.

For the first time, they managed to get a sufficient amount of 3-bromofascaplysin and 3,10-dibromofascaplysin. These compounds were used for first syntheses of the alkaloids 14-bromoreticulatate and 14-bromoreticulatine.

Researchers found that 14-bromoreticulatine selectively affects Pseudomonas aeruginosa, a bacterium that is resistant to many types of antibiotics. They also reported that 3,10-dibromofascaplysin was able to target metabolic activity of prostate cancer cells.

Moving forward

Later in 2021, the researchers hope to report the outcomes of studying how 3,10-dibromofascaplysin affects non-cancer cells.

Fascaplysin is highly toxic to healthy cells, which, until now, has limited its use as a drug.

“In our laboratory, we are trying to modify the structure of these compounds in order to reduce their cytotoxic effect on normal cells, while maintaining the necessary anti-tumor effect,” explains Dr. Maxim Zhidkov, head of the Organic Chemistry Department at FEFU’s School of Natural Sciences in Russia.

“The goal is to create a substance for targeted therapy, with a minimum of side effects for healthy cells of the body.”

The researchers speculate that it could take between 10 and 15 years before their work results in the development of a new drug.