New advances in cancer treatment are coming so quickly, it’s hard to keep up with them. This is good news for mesothelioma patients because each new development could be the first step on the path to a cure for this usually incurable cancer.
The Broad Institute of MIT and Harvard in collaboration with the Dana-Farber Cancer Institute recently announced an ambitious project to map cancer dependency. They created a website to provide easy access to their data. The information they have collected helps point the way to the most productive avenues for future research. This will, they hope, lead to more targeted therapies for people with many types of cancer, including mesothelioma patients.
The Promise of Targeted Therapies for Mesothelioma Patients
The team of researchers who worked on the Broad Institute/Dana-Farber study tested cancer cells – including two types of pleural mesothelioma cells – to determine what genes the cancers rely on to grow and reproduce. Future treatments for mesothelioma patients may use targeted therapies, based on this information, to block the strategies that mesothelioma cells use to survive.
Most mesothelioma patients get only temporary relief from the available treatments: chemotherapy, surgery, and radiation. Experimental therapies such as photodynamic therapy and immunotherapy offer the promise of extended survival times for some mesothelioma patients.
So far, however, none of these new treatments has led to a cure. As more targeted mesothelioma treatments become available, the odds of better survival times for mesothelioma patients go up. That’s why the Broad Institute/Dana-Farber project is so important, because it provides a strong foundation for future research.
What is Targeted Therapy?
Targeted therapies are treatments tailored to a very small number of mesothelioma patients or other cancer patients. To use a targeted therapy, your doctor must understand the mechanism that your cancer cells use to avoid your body’s defenses. The targeted therapy blocks the cancer cell’s ability to reproduce infinitely or to prevent your immune system from killing it or to avoid the natural process of programmed cell death.
Immunotherapies are a major type of targeted therapy that have had good results for some mesothelioma patients. Immunotherapies stimulate (or just unblock) your immune system so it can attack the rogue mesothelioma cells.
Other targeted therapies work on different elements of cell biology. Normal cells reproduce at a moderate rate and die off when they get the signal that it’s time for them to die – something that often happens when your body senses that a cell is damaged or defective. Cancer cells reproduce more quickly and stay alive even though they are abnormal. Each targeted therapy works with one of the processes our bodies use to get rid of abnormal cells.
Because they use the body’s natural processes, targeted therapy drugs are sometimes called biopharmaceuticals. Chemotherapy, which is the best current standard mesothelioma treatment, is toxic to mesothelioma cells but also to some of your healthy cells. Scientists hope that targeted treatments for mesothelioma patients will produce better results with fewer side effects than traditional chemotherapy.
What is Cancer Dependency?
The Broad Institute/Dana-Farber study looks at the genetic strategies that cancer cells use to survive. One of the things that can make a cell cancerous is a genetic mistake – a mutation or a misplaced piece of DNA. Some of these errors threaten the cell’s existence. To work around these mutations, cancer cells modify the actions of other genes in order to compensate. They become dependent on these modifications to survive. This is cancer dependency.
Once researchers know what these survival strategies are, they can create targeted treatments to outsmart the cancer cells. It is hoped that these treatments will work for mesothelioma patients and others in ways that currently available cancer treatments do not.
Barriers to Targeted Treatments for Mesothelioma Patients
The ideal of targeted treatments is exciting. Some researchers believe that the future of cancer treatment is individual therapy tailored to each patient. In reality, however, we are not there yet.
Mesothelioma patients who aren’t treated at a teaching hospital do not always get the lab work needed to determine the best targeted therapy. To understand your tumor, it needs to be genetically sequenced. This is expensive, so it is not often done. Until genetic sequencing becomes routine, most mesothelioma patients won’t get the full benefit of targeted therapies like immunotherapy.
As scientific research moves forward in leaps and bounds, however, more targeted therapies will become available. When this happens, the demand for genetic sequencing will rise and the price may fall. Someday, genetic testing and targeted therapy may become the standard of care for mesothelioma patients.
Mapping Cancer Dependency in Mesothelioma Patients
The Cancer Dependency Map project does more than provide specific data about the survival mechanics of different types of cancer cells. The Broad Institute and Dana-Farber researchers have aggregated the data. This reveals important information that will help scientists focus future research.
The researchers have shared data about how many types of cancer rely on each strategy. Their study revealed 426 different cancer dependencies. However, one or more of just 76 genes played a role in over 90 percent of the dependencies. Scientists can focus future research on targeted therapies that are likely to help the largest number of patients.
In addition, the research determined that most of the abnormalities in the cancer cells were not due to mutations. Only 16 percent of the mechanisms identified in the study were associated with gene mutations.
In fact, 82 percent of the cancer permutations were due to gene expression. Gene expression is a term for the use of a gene’s code to create a product for the cell. Gene expression usually results in the production of a protein or of RNA. In the cancer cell lines studied, cells had to turn to cell dependency survival strategies when gene expression was higher or lower than normal. This information will also be of great use to researchers in pursuing future targeted therapies.
Time is something mesothelioma patients have too little of, but, fortunately, the pace of cancer research is speeding up. Recognizing the urgency of finding better mesothelioma treatments, the FDA has allowed drug manufacturers to increase the pace of development. Because targeted therapies sometimes work for only small groups of patients, clinical trials with smaller cohorts have been accepted as proof that a treatment is market-worthy.
And all of this is good news for mesothelioma patients.