Immune System May Help Fight Mesothelioma

Proteins and toxins produced by the body’s own immune system could prove to be powerful weapons in the fight against malignant mesothelioma. 

 

Manipulating the immune system to fight cancer is known as immunotherapy.  One type of immunotherapy is utilizing natural immunotoxins, or cell killers, produced by the white blood cells to attack tumors.  Preliminary data shows that a protein produced by these cells called interleukin-4 or IL-4, may have potent cancer-fighting properties.  Researchers with the Pacific Heart Lung & Blood Institute in California are planning studies to test the toxin’s value as a way to combat mesothelioma. 

Their first challenge will be to produce enough IL-4 to conduct tests.  When enough of the immunotoxin can be synthesized according to FDA standards, the researchers plan to test it in combination with chemotherapy, hyperthermia and interferon therapy using mesothelioma cells grown in the laboratory.  If the results of the laboratory studies (in vitro) show promise, the teams will conduct studies of IL-4 in animals (in vivo) and eventually in human subjects.  

Mesothelioma, a rare cancer that attacks the tissues surrounding the lungs and other organs, is extremely difficult treat and survival beyond one year is uncommon.  According to the PHLBI website, if these planned trials prove the efficacy of IL-4, it ‘could be a key to significant progress toward a cure for this dreaded disease’.

Another substance produced by the immune system, interferon, has also shown promising results against mesothelioma in studies conducted at UCLA.  Interferons are messenger proteins that are normally produced to fight certain kinds of infections.  PHLBI researchers believe that, like immunotoxins, interferons may also play a role in fighting abnormal cells like cancer cells, by inhibiting their ability to form blood vessels.  In high does, they have already been shown to help keep melanoma cancer from recurring. 

Plans are in place for upcoming trials to combine interferon with other therapies such as hyperthermia and immune stimulating cytokines to treat mesothelioma cells in the laboratory. Eventually, interferon may even be combined with a COX-2 inhibiting drug such as Celebrex as a ‘maintenance therapy’ to keep mesothelioma tumors in check.  As with IL-4, success in the lab may lead to animal and eventual human testing at UCLA and other centers around the country.

Source:
  Mesothelioma

Worldwide Mesothelioma Rate Higher Than Expected

The global rate of the asbestos-related cancer mesothelioma is probably much higher than was previously thought.

A new study published in the National Institute of Health’s (NIH) environmental health sciences journal, Environmental Health Perspectives, estimates that for every four or five cases of mesothelioma worldwide, there is at least one more case that goes unreported.   

Malignant mesothelioma is an aggressive form of cancer that usually develops 20 to 50 years after exposure to asbestos, a mineral used for many years in a wide variety of products and applications.  The popularity of asbestos declined after it was associated with mesothelioma and other serious health problems in the 1980’s, but there is still no asbestos ban in the USA.  In addition, because it is cheap and plentiful, asbestos is especially popular in developing countries, many of whom continue to import and use it today, despite the risks.

To arrive at their numbers, the Environmental Health Perspective study’s authors looked at the correlation between asbestos use and mesothelioma deaths in 89 countries, which accounted for more than 82 percent of the world’s population in the year 2000.  The study assessed each country’s level of asbestos use between 1920 and 1970 and compared it with each country’s mesothelioma deaths between 1994 and 2008.  The United States, Russia, United Kingdom, Germany and Japan were the largest users of asbestos. Because many of the smaller, poorer countries that also use asbestos tend to have less reliable reporting practices, the authors cautioned that the actual numbers of mesothelioma cases may be even higher than the study suggests.  

“Our most important finding is the magnitude of unreported mesothelioma in countries that use asbestos at substantial levels but report no cases of the disease,” study co-author Ken Takahashi said in a press release. Takahashi says any country that uses asbestos is certain to have mesothelioma cases and countries whose use has increased, rather than decreased, since 1970 are likely to see a rise in cases in the coming decades.

Takahashi and his co-authors call on all countries to stop mining, using and exporting asbestos in order to prevent mesothelioma. The new study is the first to provide a global estimate of unreported mesothelioma cases based on asbestos use and reported mesothelioma cases. The prognosis for mesothelioma is usually poor.

Source:
  Mesothelioma