Temsirolimus, a kinase inhibitor commonly used to treat advanced renal cell carcinoma, may increase the effectiveness of chemotherapy administered in the treatment of mesothelioma, according to the results of a study reported in Journal of Thoracic Oncology (2011;6:852-863).
Mesothelioma—a cancer that is usually caused by asbestos exposure that may have occurred up to 30 to 50 years earlier—is often resistant to chemotherapy and radiation therapy. But Walter Berger, PhD, of the Institute of Cancer Research at the Medical University of Vienna (Austria), and associates have found that temsirolimus may slow the growth of malignant pleural mesothelioma cells.
Temsirolimus blocks the action of mammalian target of rapamycin (mTOR), a protein that regulates cell growth. The blockage of mTor can slow tumor growth. The Austrian team observed that temsirolimus strongly blocked mTOR-mediated signals and had a growth-stopping effect on all mesothelioma cells. However, mesothelioma cells that were resistant to cisplatin showed hypersensitivity against temsirolimus. As noted in a statement issued by the International Association for the Study of Lung Cancer to announce the study results, this suggests temsirolimus and other mTOR inhibitors might be a promising treatment strategy either in combination with chemotherapy or as a second-line treatment after chemotherapy failure.
The discovery of a promising new therapeutic strategy against mesothelioma is much needed, explained Berger in the statement. “Malignant mesothelioma is a severe human malignancy characterized by a very bad prognosis, with a mean patient survival time of less than 1 year,” he pointed out. “This unacceptable situation is mainly caused by late diagnosis combined with a distinct resistance to all forms of systemic therapy available so far.”
With the long latency period, the incidence peak of mesothelioma still lies ahead, Berger contends. As a result, “Novel therapeutic options for this devastating disease are urgently needed.”