What Is Virotherapy?

Virotherapy, which uses viruses to kill cancer cells, is a potential new technique to treat mesothelioma.

Table of Contents

Main Attractions

Viral therapy uses cancer-causing, “cancer-killing” viruses to attack cancer cells.
Researchers are actively working to improve the effectiveness of current viruses.
When paired with other treatments, virotherapy offers promising effects.
Currently, mesothelioma therapy is only available through clinical trials.

The use of viruses to target and destroy cancer cells is known as oncolytic virotherapy. Collectively, the use of viruses to treat mesothelioma is called mesothelioma therapy. Virotherapy is quickly becoming recognized as a safe and effective therapeutic option for persons suffering from malignant mesothelioma and other malignancies.

Virotherapy employs oncolytic viruses to selectively target and kill cancer cells. For example, rabies virus selectively targets nerve cells and the hepatitis B virus selectively targets liver cells. Once the cancer-causing virus has entered a cancer cell, it can destroy that cell in any number of ways. In this way, scientists can harness the natural power of cancer-causing viruses to fight cancer, such as with mesothelioma patients.

Viruses And Cancer: Early Therapy

While virotherapy is one of the most innovative cancer treatments, the link between viral infection and cancer remission has been recognized for at least the last century. There are numerous reports of cancer patients who have developed certain viral infections, temporarily in remission of their cancer. Not surprisingly, researchers have been experimenting with methods of actively infecting patients with the virus in their cancer treatment efforts.

Virotherapy Is Given With An Initial Timeline

1949: First major clinical trial in oncolytic virotherapy

22 people with Hodgkin’s disease received an active hepatitis B virus shot
7 patients in remission
Tumor size decreased in 4 patients

1950s: Two major trials were held

Mixed results were found, very similar to the first study
Some patients are in remission, but only in small numbers
Other patients had serious side effects, and some died

1974: Successful research on cancer therapy

Ninety people with terminal cancer were infected with the mumps virus live
37 are in complete remission or more than 50%
No reaction in 11 patients and a severe reaction in 7 patients

New Age Of Virotherapy

Prior to the 1970s, the virus used to infect cancer patients was a natural, unmodified form of the virus that can be found in nature. More specifically, they are extracted directly from patients with active viral infections. Since the 1970s, the fields of molecular biology, cancer biology, and virology have flourished. Virologists can now isolate individual viruses or grow purified viruses in the medium. clean. Furthermore, the virus can be attenuated (as is done during vaccine development) to eliminate severe symptoms of viral infection while achieving the desired antitumor effect. Indeed, the virus used for modern virotherapy is extremely well tolerated, even at very high doses.

Another important factor that distinguishes modern virotherapy from the trials of the 1950s is the use of combination therapy. In combination virus therapy, researchers attach a specific molecule such as a cytokine, hormone, or protein to the virus. These binding molecules can enhance the effects of the virus in a variety of ways, such as delivering the virus to the tumor or facilitating the entry of the virus into the tumor cell.

Virotherapy Oncolytic Virus

The ideal oncolytic virus should be able to do all of the following:

Find and infect all cancer cells in human body
destroy cancer cells
Does not infect healthy cells
no signs of serious infection or illness

Some natural viruses are capable of acquiring some of these, but no single, natural virus meets all of these criteria. However, the researchers took existing viruses and developed several strategies to modify them to be closer to this ideal.

Adenovirus is an example of a naturally occurring virus that has evolved into a more aggressive cancer-causing virus. The genetic material of the adenovirus can be easily manipulated, and has been extensively modified and tested for decades. Adenovirus infection with the natural form of the virus usually causes mild to moderate symptoms for several days. However, in its modified form, oncolytic adenovirus is well tolerated.

Virotherapy Treatment Process

Special virotherapy for the treatment of mesothelioma is currently only available as part ofClinical trials.

Typical Requirements For Virotherapy Candidates

As an experimental therapy, patients often have to be in the advanced stage or have a poor response to other therapies.
Most mesothelioma candidates involve the pleura because the cancer-causing virus is injected into the space between the chest wall and the lungs (pleural space).

Mesothelioma therapy can be done in a variety of ways. In general, the patient must undergomesothelioma staging with histological and radiological studies. Tumor-specific measurements (such as chest CT or MRI) may be taken before treatment to monitor the effects of the cancer-causing virus. These images are compared with images taken after completing virotherapy treatment.

Tumor-specific promoters can be identified and used to ensure that oncogenic viruses specifically target mesothelioma cells and do not affect healthy cells. For example, the researchers modified adenoviruses to contain a tumor-specific promoter called Survivin.12. This modification improved the ability of the adenovirus to infect mesothelioma cells and prevented it from infecting other cells. Other viral binding agents, such as cytokines, may enhance the tumor-killing effects of cancer-causing viruses.

Virotherapy and Other Experimental Treatments

Mesothelioma therapy may be even more effective when combined withother traditional and experimental therapies.Laboratory studies have shown that drugschemotherapy with oncolytic viruses were more successful in killing mesothelioma cells when combined with cisplatin and pemetrexed, a standard treatment for malignant mesothelioma.

Because viruses directly affect cancer cells and stimulate the immune system, there is great potential to combine virotherapy with immunotherapy. Some of the modifications made to oncolytic viruses are actually a form of immunotherapy. For example, when the vaccine virus is conjugated with the cytokine IL-2, the virus combination not only destroys malignant mesothelioma cells from the inside, but also stimulates a strong immune response against cancer cells, their destruction is done by right.

Laboratory studies and early clinical trials have shown that the combination of therapeutics and viral immunotherapy is a powerful combination, even in tumor cancer cells. malignant mesothelioma. Clinical trials are being recruited to test this combination in patients.

Clinical Trial Of Virotherapy

To date, the main viruses used in mesothelioma therapy are adenovirus, herpes simplex virus, measles virus, and vaccine virus. Approximately half of the 60 patients with malignant mesothelioma treated with oncolytic adenovirus had a clinical response. Initial trials with the modified vaccine virus showed that the oncolytic virus was safe but did not significantly disrupt mesothelioma cells. Trials for the modified immunized virus, GL-ONC1, measles oncogenic virus (MV-NIS), herpes simplex virus and other latent viruses are underway. Continuing cancer research into new treatments such as immunotherapy, gene therapy, and oncolytic virus therapy offers hope for a cure.