Mesothelioma Gene Therapy

What Is Mesothelioma Gene Therapy?

Gene therapy for mesothelioma is a broad category that refers to several emerging treatment approaches. They involve the novel science of genetic modification. It wasn’t until 2017 that the U.S. Food and Drug Administration approved a gene-therapy-based cancer treatment for the first time.

Gene Therapy Facts

• Available to people with mesothelioma through clinical trials
• Bears risk of severe side effects and complications
• Broad category including several experimental treatment approaches
• Involves genetically modifying cancer cells, viruses or immune cells

Many researchers believe that just as faulty genes are the key to cancer formation, modified genes may be the key to cancer treatment. Mesothelioma researchers are hopeful that gene therapy will bring us closer to a cure for mesothelioma.

Immunotherapy with Genetically Modified T-Cells

The most exciting recent development in gene therapy for mesothelioma lies at the intersection of gene therapy and immunotherapy. The first gene therapy for cancer the FDA approved is Kymriah and is generically referred to as CAR T-cell therapy. Kymriah’s makers call it a “living drug,” because the patient’s own immune cells are extracted and reprogrammed to target cancer.

Researchers in 2021 concluded anti-mesothelin CAR T-cells are effective. Researchers in clinical trials are studying it in combination with checkpoint inhibitors and other therapies. Scientists hope this new therapy will improve mesothelioma prognosis.

CAR T-cell therapy is a targeted cancer treatment. But it also has significant limitations. Kymriah is FDA-approved only for leukemia, it’s extremely expensive and it comes with the risk of severe side effects.

Inserting Tumor-Suppressing Genes

The most obvious gene therapy approach for mesothelioma is to fix the genetic fault that causes cells to become cancerous in the first place. To perform this medical feat, however, scientists have to overcome two major challenges.

First, researchers haven’t been able to pinpoint a specific gene that can stop the progression of mesothelioma in most people. The likeliest candidates are natural “tumor-suppressing genes.” 

They prevent genetic mutations or ensure mutant cells self-destruct before they grow into tumors. The p53 gene, the BAP1 gene and microRNA gene 16 have all been studied as genes that may be able to stop the progression of mesothelioma.

Second, inserting these tumor-suppressing genes requires a microscopic delivery vehicle. Called vectors, they can penetrate deep into a tumor. Genetically modified viruses and nanoparticles are both in development as gene therapy vectors.

Engineering Viruses to Target Cancer Cells

Instead of changing cellular DNA, some researchers focus on altering deadly viruses to kill only cancer cells. This method, called virotherapy, began by chance when doctors noticed many cancer patients who caught measles experienced tumor shrinkage. Since then, scientists have developed modified measles viruses as experimental treatments for cancers, including mesothelioma.

In one trial, researchers injected a special measles vaccine strain directly into mesothelioma tumors. This treatment infects the cancer cells with the virus and also triggers the body’s immune system to attack the cancer.

Chemotherapy Guided by ‘Suicide Genes’

Scientists are working on vectors that can insert special “suicide genes” into cancer cells. The goal is to create a vector that infects all the cancer cells in a tumor but leaves healthy cells alone. This would allow a targeted chemo called suicide gene therapy.

The suicide gene makes cancer cells produce an enzyme that changes a harmless drug into a deadly toxin. This process kills the cancer cells while sparing healthy ones.

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