Lobna Ali

🧬 HOW DOES A PERSONALIZED mRNA CANCER VACCINE ACTUALLY WORK? As an oncologist, and also as a university professor, I strongly believe that understanding how a new treatment works is often the best way to understand why it may eventually change our clinical practice. So, what exactly is a personalized mRNA cancer vaccine? The concept is both sophisticated and surprisingly intuitive. 1️⃣ Start with the patient's own tumor 🧬 Every cancer is genetically different. By sequencing tumor DNA and RNA, and comparing this information with normal tissue , we can identify tumor-specific mutations. Some of these mutations generate abnormal proteins that are not present in healthy cells. These are called neoantigens. And importantly, they can become molecular "flags" allowing the immune system to distinguish cancer cells from normal cells. 2️⃣ Select the best targets 🎯 Not every mutation will generate an effective immune response. Bioinformatic algorithms therefore analyze the patient's tumor and predict which neoantigens are most likely to be recognized by their immune system. In the case of intismeran autogene, up to 34 patient-specific neoantigens can be selected. 3️⃣ Build an individualized mRNA therapy 💉 Here comes the fascinating part. A synthetic mRNA sequence encoding those selected neoantigens is manufactured specifically for that individual patient. Think about what this means. We are no longer simply choosing the best available drug for a patient. We are manufacturing a treatment based on the molecular identity of that patient's own cancer. 4️⃣ Teach the immune system what to recognize 🛡️ After administration, the mRNA enters cells and provides the instructions to produce the selected neoantigens. These neoantigens are processed and presented to the immune system, activating tumor-specific CD4+ and CD8+ T cells. The objective is to generate an immune response capable of recognizing cells carrying those same neoantigens. 5️⃣ Let T cells search for the cancer 🔎 Those activated T cells can then recognize tumor cells displaying the corresponding antigens and potentially destroy them. This is why combining personalized vaccination with PD-1 blockade such as pembrolizumab makes so much biological sense: 🎯 The vaccine may teach the immune system WHAT to attack. 🔓 Checkpoint inhibition may help the immune system KEEP attacking it. And this is where, in my view, the concept becomes much bigger than one drug or one tumor type. For many years, we have defined precision oncology as: “the right treatment for the right patient.” Personalized mRNA vaccines introduce an even more ambitious paradigm: “a treatment designed and manufactured specifically from the molecular characteristics of one patient's cancer.” @OncoAlert @_SEOM @moderna_tx @GEPAC_ Figure adapted from: doi:10.3390/cancers17091408.