Fighting Mesothelioma with Immunotherapy
James P. Allison, whose research pioneered the field of cancer immunotherapy, recently described his work to the New York Times in an interview.
Cancer immunotherapy isn’t an entirely new field. In 1890 a doctor named William Coley at Memorial Hospital (now Memorial Sloan-Kettering Cancer Center) noticed that cancer patients who developed post-surgical bacterial infections had fewer reoccurrences than those who didn’t get sick. Coley theorized that the infection triggered a therapeutic immune response and went on to develop a cancer treatment made from heat-killed bacteria.
Allison notes that Coley’s ideas disappeared when radiotherapy was popularized. Extensive efforts to develop anticancer vaccines were undertaken in the 20th century, but time and again cancer provided capable of thwarting the immune system and the idea of cancer immunotherapy was abandoned.
Allison brought new hope to the field in the 1990s with work at his lab at the MD Anderson Cancer Center in Texas.
“My team and another group showed that there was a molecule on T-cells that actually acts like an off switch or a brake pedal when T-cells encounter an infected cell,” said Allison. “I wondered whether we could block this off switch to keep the T-cells turned on. And that’s what we did. We developed an antibody to plug this off-switch.”
Following successful experiments on mice, the FDA in 2011 approved the drug Yervoy for late stage melanomas. A follow up study found that 22% of melanoma patients taking Yervoy survived 10 years or longer. According to Allison, melanoma patients typically survive seven to twelve months.
Immunotherapy and Mesothelioma
Researches at Memorial-Sloan Kettering Cancer Center—the same hospital where more than a century ago Dr. Coley experimented with cancer immunotherapy—described in a 2014 study how T cells could be genetically programmed to recognize a protein called mesothelin that is present in around 90 percent of mesothelioma tumors. Mouse studies showed that the reprogrammed T cells were able to find and eliminate pleural cavity tumors. Equally promising, the T cells killed the cancer when new tumors were introduced.
The researchers plan to launch a clinical trial for patients with solid chest cavity tumors, including mesothelioma tumors, sometime this year.
Pleural mesothelioma is the most common form of mesothelioma, which is diagnosed in roughly 3,000 U.S. patients each year. Chemotherapy and radiation are generally ineffective treatments for mesothelioma, and surgical treatments aren’t a good fit for all patients.
Thanks to contributions from researchers such as Dr. Allison, immunotherapy has the potential to be the new standard of care for one of the deadliest cancers out there.
