Guillermina Ferro Tests Radiopharmaceuticals for Cancer Detection and Treatment

Guillermina Ferro Flores, a scientist who won the 2020 National Science Award in the field of Technology, Innovation and Design, is focusing her work on improving the quality of life and survival of cancer patients through nuclear medicine treatment. She leads an interdisciplinary group of women at the National Institute of Nuclear Research (ININ) studying radiopharmaceuticals, radioactive compounds with the ability to act on specific organs, tissues or cells in the human body. These compounds facilitate imaging that aids in the detection of primarily oncological, neurological, and cardiac diseases and can also be used in treatment.

In an interview with The Day, she, who also heads the National Laboratory for Research and Development of Radiopharmaceuticals at the ININ, expressed that the pursuit of knowledge produces happiness. A life dedicated to others is worth living.

She encourages persistence against obstacles, stating that no matter the political or economic obstacles we face, our common goal is not to abandon our dreams. Dreams are not achieved, they are built. As a woman, you often have to fight against barriers, and even if they push you back, you must keep going. It’s about being persistent and never giving up on your desires. The day you lose the desire to win, you have lost everything.

Ferro Flores, who holds a doctorate in science with a specialty in medical physics and teaches at the Faculty of Chemistry of the National Autonomous University of Mexico (UNAM), explained that the radioactive substance, or radionuclide, is administered intravenously in a pharmaceutical solution. This gamma radiation does not disrupt the system and the component containing the chemical element technetium moves to the affected site, generating an image for diagnosis.

She further explained that If the patient is a good candidate, we use the same sensor and apply lutetium, which has beta rays with high destructive energy. This enters the bloodstream and rapidly flows into a highly vascularized tumor. The drug interacts with the proteins on the surface of the neoplasm and begins to attack the cancer cells, reducing the tumor mass in a targeted manner without damaging other organs. This method is effective in reaching all metastases, unlike external radiation therapy.

Protective of the immune system

She further elaborated that everyone has T cells that manage the immune system. These cells have a factor, PD-L1, that when activated, creates immunity. However, cancer cells can trap these T cells and block the immune response. Biological therapies can separate these cells and imaging can determine whether or not PD-L1 is expressed, enabling personalized medicine.

Ferro Flores also spoke about a molecule that reveals the amount of sugar a tumor absorbs. This molecule is not just associated with oncological cells, but also the microenvironment that supports them: macrophages, cells that stimulate enzymes leading to cancerous mutations, and fibroblasts, tissues that secrete proteins with collagen, which make up 90 percent of the tumor. This information is crucial for a patient’s prognosis as some cancers are associated with immune factors, which can make them resistant to treatments like immunotherapy.

Cardiac regeneration

Ferro Flores also discussed a radiopharmaceutical that was transferred from the ININ to the Belgian company Ilusa, which enables the visualization of areas impacted by a heart attack. When the heart stops receiving blood flow, that part dies and no longer receives oxygen. This treatment allows for the observation of this tissue through activated fibroblasts. If they remain activated for a long time, the heart hardens and in the long run, it will not be able to expand and close, or beat. Therefore, monitoring the regeneration of the organ is very crucial..

She concluded by discussing the two techniques for obtaining molecular images: positron emission tomography (PET/CT) and single photon emission tomography (SPECT/CT). Mexico has 156 nuclear medicine centers, 51 PET and 167 SPECT equipment, which are significantly fewer than in other countries. She hopes to expand the reach of their work with a pilot center project aimed at bringing advanced technology to those with limited resources.