Oral anticancer agent slows mesothelioma progression in lab mice
Researchers in Japan have discovered that an oral drug widely used to treat a variety of cancers in Asia slowed the spread of pleural mesothelioma cells in mice.
Not yet approved for use in the United States, S-1 is a chemotherapy drug that has been successful in the treatment of gastric, colorectal, head and neck, breast, non-small cell lung and pancreatic cancers. Developed by the Japanese drug maker Taiho Pharmaceutical Co., the oral agent is designed to prevent the growth of tumors, as well as to enhance the effectiveness of Fluorouracil, which is used to treat several types of cancer.
A study published in the medical journal Cancer, Chemotherapy and Pharmacology reports that doses of S-1 and fluorouracil significantly reduced tumor growth in mice implanted with certain lines of mesothelioma cells and prolonged their survival.
Pleural mesothelioma is the most common type of mesothelioma, a rare cancer that develops in the mesothelium, a membrane that lines many of the body's organs. It is caused when asbestos fibers become trapped in the spaces between the mesothelial cells. The disease is often fatal within 14 months following diagnosis and kills an estimated 15,000 to 20,000 people annually around the world.
Pleural mesothelioma is usually treated with surgery, chemotherapy or radiation therapy, or some combination of those options. However, treatment is difficult because it can take decades for symptoms to appear, by which time patients are often older and have advanced stages of the disease.
To replicate how the disease progresses in humans, the Japanese researchers allowed the mesthelioma cells to grow in laboratory mice and eventually produce tumors. The administration of S-1 was delayed 10 days to allow the disease to progress. They found that the S-1 “significantly inhibited the tumor progression,” and prolonged the survival of the mice, suggesting that S-1 might be effective against pleural mesothelioma in humans.
The researchers said the study was the first to investigate the effect of S-1 on the disease. The drug is currently in Phase III clinical development in the United States and has not yet received approval from the U.S. Food and Drug Administration.