Treating Mesothelioma - Gene Therapy

Advancements in treating mesothelioma have resulted in the creation of a number of different treatment options and techniques that are available to all mesothelioma patients today. The types of treatment options and techniques for treating mesothelioma will, however, depend greatly on a variety of factors. These include the overall health and age of the patient and the heart and lung health, as well as the type of mesothelioma cancer cells and how they appear under a microscope, the stage of the mesothelioma, the size of the tumor, the amount of fluid in the abdomen or chest, and whether or not the mesothelioma has been diagnosed recently or if it has recurred.

These and other factors can be tested using a wide range of procedures that will help bring the physician one step closer to designing the most effective treatment plan to help manage the patient’s mesothelioma. Diagnostic methods and procedures for diagnosing mesothelioma include: physical examination, chest x-ray, complete blood count or CBC, sedimentation rate, bronchoscopy, or a cytologic exam. A biopsy can also be performed. The different types of biopsy methods used include fine needle aspiration biopsy or FNA, thoracoscopy, laparotomy, and thoracotomy.

Once the type of mesothelioma, stage, and overall health of the patient have been determined, the doctor will explore the various treatment methods. The treatments and methods used for treating mesothelioma can be divided into two types: traditional mesothelioma treatments and new mesothelioma treatments. New mesothelioma treatments include gene therapy, photodynamic therapy or PDT, immunotherapy, intensity modulated radiation therapy or IMRT, and the development of new chemotherapy agents. Traditional mesothelioma treatments include: surgery, chemotherapy, and radiation therapy or radiotherapy. In many cases a trimodality approach is employed, which means several treatments are combined for the best outcomes, for a better chance at long-term survival, and/or a better quality of life.

Gene therapy may be used in treating mesothelioma in an attempt to correct cancer at the DNA level. It is typically used to treat fatal and disabling diseases and there are several types including replacement gene therapy and knockout gene therapy. Knockout gene therapy literally attacks the genes that cause tumors to form and prevents them from forming. Replacement gene therapy replaces a missing or mutated gene with a healthy clone of the gene. This helps to manage cell growth and division.

It should be noted that the p53 gene is the most common gene mutated in cancer. This gene is at the center of gene replacement. While other newer methods have met with little success, p53 gene replacement shows promise in treating aggressive forms of cancer. It inhibits cell growth, it inhibits the development of the tumor’s blood supply (angiogenesis), and it induces cell death or apoptosis. Possible side effects of gene therapy may include nausea, vomiting, fever, and bleeding.

Photodynamic therapy or PDT destroys cancerous cells by using fixed frequency light to activate certain photosensitive drugs, which have accumulated in the body tissues. These photosensitizing drugs are administered to patients intravenously and they take only a few days to absorb into the diseased cells – which are referred to as “treated cancer cells” at this point. The treated cancer cells are exposed to the laser light, which is delivered to the cancer site by a physician using a fiberoptic device. Once the agent in the treated cancer cells absorbs the laser light, surrounding cancer cells are destroyed by a kinetic form of oxygen. Side effects of photodynamic therapy may include nausea and vomiting as well as a metallic taste on the palette. The main side effect of photodynamic therapy is skin sensitivity as well as eye sensitivity to light.

Immunotherapy is also called biological therapy and immune augmentative therapy. This type of approach to treating mesothelioma involves the body’s immune system. Immunotherapy works with the body’s immune system to help fight cancer and to also help control how the patient’s body reacts to certain cancer drugs. While doctors are not entirely sure how immunotherapy helps the immune system fight cancer, they are confident that it does keep cancer from spreading to other parts of the body, that is stops or slows the growth of deadly cancer cells, and that it makes it easier for the immune system to destroy cancer cells. Immunotherapy may be used depending on the type of cancer and the stage of the cancer. It may also be based on any treatments that may have already been used. In some cases, immunotherapy is the very best option for treating mesothelioma or other types of cancer.

Immunotherapy may be used alone or in combination with chemotherapy and radiation.
Treatment may come in the form of pills or shots that the patient can self-administer at home. In some cases, patients may have to stay at the hospital or clinic to receive immunotherapy via IV. Depending on the delivery method, treating mesothelioma with immunotherapy may take place once a day, several times a day, weekly or once a month. Immunotherapy side effects may include loss of appetite, fatigue, nausea, vomiting, fever muscle aches, chills, low blood pressure, bone pain, and swelling or rashes at the injection site.

In addition to gene therapy, there are several other new mesothelioma treatments available including angiogenesis therapies, antineoplaston therapy, mesothelioma clinical trials, interferon and interleukin therapy, and radiofrequency ablation. A wide variety of complementary and alternative mesothelioma treatments also exist such as herbal products, special diets, homeopathic medicine, acupuncture, therapeutic massage, high dose vitamin C, laetrile (amygdalin, extracted from fruit pits), and Eastern medicines.

New mesothelioma treatments such as gene therapy, as well as photodynamic therapy (PDT), and immunotherapy offer new hope for doctors and mesothelioma patients. Doctors, scientists, and researchers are attempting to further develop these new treatment modalities, with the hope that they will be successful where traditional treatments have failed. To date, these new treatments for mesothelioma have not quite measured up to traditional methods, but they are currently being used in conjunction with traditional methods and they are, of course, constantly being monitored and assessed.

 

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