Clapper, Patti, Schweizer and Mason

Kidney Cancer Drug Also Combats Mesothelioma Tumors

During a study of Temsirolimus, (brand name Torisel) a drug most often used to treat renal (kidney) cancer, scientists in Austria discovered that the drug may also combat the growth of mesothelioma tumors as well, specifically pleural mesothelioma. 

Mesothelioma is a specific type of cancer caused by inhalation or ingestion of asbestos fibers.  The body’s natural response to these foreign invaders is to build up tissue around them so that they can be isolated.  However, these masses of tissue can eventually turn cancerous and lethal.  Due to the nature of the disease, symptoms of mesothelioma may not even arise for up to 50 years after initial asbestos exposure. 

Malignant pleural mesothelioma is one of the most aggressive types of mesothelioma and occurs when asbestos fibers imbed themselves in the lining of the lungs.  Because the cancer is not often diagnosed until it is in the late stages of development, most pleural mesothelioma patients are given only a few months (often less than a year) to live.  

While pleural mesothelioma is resistant to many types of treatment, there is some hope that research published in the May issue of the Journal of Thoracic Oncology concerning Temsirolimus may lead to a treatment or even a preventative measure that will work.

Temsirolimus belongs to a class of drugs called protein kinase inhibitors.  These drugs work by inhibiting the protein rapamycin (mTOR) which plays a key role in modulating how quickly cells within the body grow. 

The drug essentially slows, and in some cases even stops, the growth of cancerous tumors by depriving the cells within those tumors of a necessary building block.  Even cells that were resistant to cisplatin, a more common chemotherapy drug, showed hypersensitivity to temsirolimus.

Professor Walter Berger, PhD, of the Institute of Cancer Research at the Medical University of Vienna coauthored the study and his team was able to "demonstrate that inhibition of the major oncogene mTOR is active against human mesothelioma especially after development of chemotherapy resistance both in vitro and in vivo."

This line of research mirrors much of the new types of treatments currently being developed to fight deadly mesothelioma.  Since the disease has proven nearly immune to traditional treatments which attempt to destroy tumors after they grow, this new thinking suggests that it may be possible and more feasible to stop them from growing in the first place. 

While the study was preclinical in nature, Berger suggests that the success the team had should lead to “clinical trials involving mTOR inhibitors as a novel anti-mesothelioma strategy."