What is Targeted Therapy?
Targeted therapy is a treatment that doctors may use to fight cancerous tumors. Specifically, medications that can pinpoint and target cancerous cells and then stop them from growing and spreading. As researchers continue to discover more about gene and protein changes and their relation to the development of tumors, they fight to reduce the harmful side-effects that can sometimes come with other cancer treatments.
Procedures such as chemotherapy and radiation generally have extreme side-effects due to the medication attacking both diseased and healthy cells versus targeted therapies that only attack specific cells.
Mesothelioma and Targeted Therapy
A type of cancer that can develop in the lining of the lungs (pleura), the heart (pericardium), or abdomen (peritoneum), mesothelioma is a disease that is caused by prolonged exposure to a harmful substance known as asbestos. This disease has seen rising cases over the past 60 years, due to the fact that asbestos was once used in many different construction capacities before it was known as a toxic carcinogen (cancer-causing), and even sometime after. The U.S. Military was also a large user of asbestos in military vehicles, navy ships, shipyards, barracks, automobiles, and more.
Recently, over the past decade, researchers have been testing the effect of targeted therapies against mesothelioma in clinical trials, to positive affect.
Is Targeted Treatment Right for Me?
Only your doctor can make this call. To determine this, your doctor will test the cancerous tumors to ensure that there are workable targets the treatments can locate. This test is usually done via biopsy or the sampling of a tumor by extraction. The sample is then sent to a lab to be examined.
Two veterans with similar mesothelioma types, exposure, and medical histories may even have different targets, causing the medication to lose its effect. Additionally, a doctor may deem it necessary for the veteran to undergo prior treatments, such as surgery.
Types of Targeted Therapies
There are two main types of targeted therapies: monoclonal antibodies and molecule medicines. Monoclonal antibodies are larger and fight cancer cells on the surface, or surrounding areas, while molecule medicines are small enough to jump into cancer cells and destroy them. Monoclonal Antibodies and Molecule Medicines have lower subtypes that are grouped based on what specific cells they target.
If the doctor needs to inject medicine straight into the tumor, they can sometimes use the small monoclonal antibodies to launch treatments directly into the unhealthy cells. This can be administered through IV as a shot or intravenously. The medications usually end with the stem “-mab.” Three monoclonal antibody types are:
- Bevacizumab – directed at the circulatory system
- Cetuximab – targeted at tumors
- Ipilimumab – attacks the immune system
Signal Transduction Inhibitors
One example of an inhibitor is the signal transduction inhibitor. Signal transduction inhibitors block signals that enable cells to divide excessively, and are the most common targeted therapy.
These inhibitors minimize the development of blood vessels for nutrients and oxygen that cells form that cancer cells form. With mesothelioma and other cancers, the target is called vascular endothelial growth factor (VEGF) and is a substance that works with the drug Bevacizumab, also known as Avastin. It’s usually administered as a supplement to chemotherapy medications pemetrexed and cisplatin. The goal is to stop tumors from growing by blocking the nutrients and oxygen they need to develop.
This treatment permeates cell membranes and attacks targets from the inside of a cell. Molecule medicines halt the enzymatic activity of a specified protein. Medications generally end with the stem “-ib.” Three molecule medicine variations include:
Bortezomib – Proteasome inhibitor
Imatinib – Tyrosine kinase inhibitor
Seliciclib – Cyclin-dependent kinase inhibitor
Gene Expression Modulators
This method of targeted therapy modifies the specific proteins that are responsible for the abnormal instruction or expression of cancer cell genes.
Apoptosis occurs when cells go through their lifecycle or become damaged, and die. What makes cancer cells so harmful is that they avoid this natural process. Apoptosis inducers force abnormal cells to go through this phase.
Also a form of targeted therapy, immunotherapies locate and fight tumors by boosting the immune system. Other immunotherapies highlight the cancer cells so that they’re simpler to find and destroy.
Side-Effects of Targeted Treatment
All cancer treatments have their own set of side effects, some worse than others. Fortunately, since targeted therapy can be focused on abnormal cells versus all cells (such as with chemotherapy or radiation), there are much less severe side effects. The most common ones a veteran might experience are:
- Diarrhea or nausea
- Lack of appetite
- High Blood Pressure
- Sores in the mouth
More rare side effects include:
- Blood clots
- Severe bleeding
- Holes in the colon
Visit your doctor immediately if you begin to experience any of these side effects after undergoing targeted therapies. There are medications your doctor can provide that can relieve side-effects.
Discuss It With Your Doctor
Don’t hesitate to reach out to your doctor about any questions you may have regarding your medical condition. Your oncologist has many resources available for all your questions about mesothelioma, targeted treatments, complementary therapies, and more.