New Mesothelioma Drug Discovered in Sea Squirt Toxin
A unique drug derived from the Caribbean sea squirt shows impressive effectiveness in stopping the growth of mesothelioma tumor cells.
Researchers at the Medical University of Vienna in Austria discovered that trabectedin, a toxin the coral-like animal uses against predators, might soon be applied in the treatment of mesothelioma.
“It has looked very promising to this point,” Walter Berger, group leader at the Institute of Cancer Research, University of Vienna, told Asbestos.com. “It’s a fascinating new substance — from its origins to its mode of action.”
A European pharmaceutical company has been harvesting the bottom-dwelling marine organism and extracting the toxin to produces the potentially life-extending drug.
The Molecular Cancer Therapeutics journal published the study earlier this month. Berger’s team, which includes thoracic surgeon Dr. Alireza Hoda, focuses on the development of novel strategies for therapy-refractory cancers such as mesothelioma, brain tumors and lung cancer.
In the recent study involving mesothelioma, trabectedin served as an effective chemotherapy-like agent that targeted DNA and delivered an immune response. It also showed great synergy when combined with cisplatin, the current standard-of-care chemotherapy.
“We found excellent activity, compared to many drugs that have been tried,” Berger said. “Mesothelioma, as you know, is very difficult to treat. This was encouraging.”
The U.S. Food and Drug Administration in October 2015 approved trabectedin for the treatment of advanced or inoperable soft tissue sarcomas. Although the National Cancer Institute sanctioned the drug under its Natural Products Branch, the drug chemically synthesized in the U.S.
Trabectedin as a Mesothelioma Treatment
Trabectedin could be a new development in the treatment of malignant pleural mesothelioma.
Doctors diagnose an estimated 3,000 new cases of mesothelioma, a rare and aggressive cancer caused by exposure to asbestos, annually in the U.S. The disease typically carries a prognosis of 6-18 months.
In the preclinical study, researchers tested trabectedin on 13 mesothelioma surgical specimens, six mesothelioma cell lines and two nonmalignant pleural tissue samples. Trabectedin prompted a dose-dependent cytotoxic effect on all mesothelioma cell cultures but a considerably lesser effect on the nonmalignant samples.
The drug generated a better response when combined with cisplatin, and then with a group of proteins that typically regulate cell death by inducing apoptosis.
Drug May Treat the Sarcomatoid Mesothelioma Subtype
The research showed a surprisingly impressive response with the sarcomatoid cell type of mesothelioma. The sarcomatoid subtype — the least common of the cell types and the most resistant to today’s therapies — often leaves patients with little hope.
Trabectedin prompted a significant improvement in the effectiveness of cisplatin against sarcomatoid cells in the lab.
Doctors in Europe and Japan are administering lurbinectedin, another version of trabectedin, in combination with other chemotherapy drugs to treat inoperable ovarian cancer.
Early results are promising, according to Dr. Diego Cortinovis, who presented the drug’s effectiveness at the annual American Society of Clinical Oncology meeting in Chicago.
- Hoda, M.A. et al. (206 August). Trabectedin is active against malignant pleural mesothelioma cell and xenograft models and synergizes with chemotherapy and bcl-2 inhibition in vitro. Retrieved from http://mct.aacrjournals.org/content/molcanther/early/2016/08/10/1535-7163.MCT-15-0846.full.pdf
- Metaxas, Y. et al. (2016, July 14). Combination of cisplatin and lurbinectedin as palliative chemotherapy in progressive malignant pleural mesothelioma: Report of two cases. Retrieved from https://www.ncbi.nlm.nih.gov/pubmed/27440191