Last updated on:January 4th, 2023
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Melanoma is an aggressive type of skin cancer originating in melanocytes. Most melanoma patients have localized disease that is treatable by surgery. Nevertheless, recurrence is frequent. In advanced melanoma, the disease is spread throughout the body and surgical removal alone is not sufficient. Melanoma incidence and mortality are highest in patients over 70 years of age.
Current treatments for melanoma
The approach to treatment is dependent on the stage of the disease. Local and regional disease has been treated with bacillus Calmette Guérin (BCG), interleukin-2, or interferon alpha. Both the anti-tuberculosis vaccine and the two proteins are able to induce anti-tumor immune responses. However, these approaches generally have been found to have a transient effect and may exhibit significant toxicity. When possible, intralesional, rather than systemic, interleukin-2 has been used in order to avoid systemic toxicity.
Advanced melanoma can be treated using immune checkpoint inhibitors and other approaches, including kinase inhibitors and other small molecules. Inhibition of immune checkpoints reduces immunotherapy resistance, facilitating the exploitation of immunotherapy to inhibit tumor growth.
Gene therapy approach for melanoma
The gene therapy approach for melanoma consists of injecting a tumor with artificial viral particles containing specific genetic components. In the patient, these genetic components will generate a source of antigens, promoting the recruitment of immune cells. Recruited immune cells induce immune responses locally (in the injected tumor) and systemically (in cancer cells outside the injected tumor). Therefore, this therapy is able to eliminate the tumor, as well as distant malignant cells.
In 2015, talimogene laherparepvec was approved by the Food and Drug Administration (FDA) of the United States for the treatment of melanoma-associated cutaneous, subcutaneous or nodal lesions that are unable to remove by surgery or that are recurrent after surgical removal. Talimogene laherparepvec is effective both in monotherapy and in combination with immune checkpoint inhibitors.