A melanoma vaccine is getting closer: how will it work?
Recently, companies Moderna and Merck announced that a melanoma vaccine could be ready by 2025. In fact, they have already begun clinical trials to develop innovative therapies against this disease.
Every year they are diagnosed around the world about 325,000 new cases of melanoma. This figure highlights the need for innovative and effective strategies to combat one type of skin cancer. more aggressive and deadly that they know each other.
Anatomy of a killer
When the skin cells responsible for producing the pigment that gives us color perception abnormal transformation and begin to grow uncontrollably, they form a malignant tumor called melanoma, which can expand and spread to other parts of the body.
Impact ultraviolet (UV) radiation from sunlight This is one of the main risk factors along with genetic predisposition and history of severe sunburn and repeated throughout life. It is estimated that about 80% of skin melanomas occur on apparently healthy skin. This means that only In 20% of cases, the cause is a previous skin injury.like a mole.
Although the appearance of new moles is common before the age of forty, it is necessary. monitor any changes. This monitoring is based on the ABCDE (asymmetry, edges, color, diameter and evolution) system for early detection possible malignant lesions.
When the immune system becomes an accomplice of tumor cells
The immune system plays decisive role in recognition and elimination of cancer cells, including melanoma cells. Like military squadrons, immune cells constantly patrol our skin in search of abnormal cells it can put our health at risk.
This process is called immunosurveillanceand is based on the recognition of antigens, cell surface molecules that signal the immune system about the presence of foreign objects. They are “flags” that identify malicious cells and allow immune cells to mobilize to destroy them.
However, there are cases when cancer cells manage avoid immune detection or they use tactics to suppress their response, opening the way for the tumor to progress.
Risks of immunotherapy
Nowadays, studying the ability of cancer cells to evade the immune system has become therapeutic target of great interest and relevance. If we know what cells do to put the immune system to sleep, we can develop strategies to “wake him up” and thus fulfills its protective function.
However, these treatments are not always effective and can sometimes cause hyperreactivity of immune cells. That is, once activated, they attack not only the tumor, but all the cells of the body.
Faced with this dilemma, the possibility arose of selectively targeting immune cell activity only to tumor cells. And this is where it comes into play. another branch of immunotherapy: development of new cancer vaccines. The key is to develop tools that help the immune system recognize the tumor and target it.
Vaccines to the rescue
Several investigations are currently underway types of melanoma vaccinesall of them are based on the ability of cells to recognize surface antigens.
On the one hand, there are peptide-based vaccines. That is, those antigens that usually carry melanoma cells, are produced in a laboratory and administered as an antidote. In this case the strategy teach your immune system flags what you have to look for.
On the other hand, the use of specific cells of the immune system (dendritic cells) capable of recognizing flags, determining whether they belong to healthy or diseased cells and teach them to the cells that should eliminate them. Clinical trial completed 70% risk reduction mortality by combining each patient’s own dendritic cells with a compound that stimulates the immune system. Although this study had limitations such as a small number of participants, the results are encouraging.
And finally there is RNA-based vaccinessuch as one developed by Moderna and Merck that works similarly to a drug developed against Covid-19.
While the Moderna coronavirus vaccine had pathogen S protein RNA sequenceThe new drug, whose technical name is mRNA-4157 (V940), includes genetic information to create flags specific to a patient’s tumor. When RNA enters body cellsthey begin to produce large quantities of these flags, making it easier for the immune system to recognize and therefore its ability to detect cancer cells.
This treatment is being tested on patients. melanoma with metastases, the risk of relapse is high. The vaccine was combined with a drug that stimulates the activation of the immune system and, according to preliminary data, reduced the risk of relapse or death by 49% compared to exclusive treatment with the drug. Combination therapy also led to improvement long-term disease-free survivalreducing the risk of developing metastases in other organs by 62%.
Without a doubt, the results are promising and aim to improve melanoma treatment. According to Moderna senior vice president and head of development, therapeutics and oncology Kyle Holen, the entire team can’t wait to share this data with the community and give hope to people affected by the disease and their families.
Cristina Penas Lago, Doctor of Biomedical Research, Postdoctoral Researcher, University of the Basque Country / Euskal Herrico Unibertsiatea
This article was originally published on The Conversation. Read the original.