A research team at Lund University in Sweden has identified a specific type of cell, known as foam cells, that plays a significant role in the progression of glioblastoma, an aggressive form of brain cancer. Their study, published in Science Translational Medicine, reveals how these cells accelerate tumor growth and shows that their harmful activity can be suppressed with a drug originally developed for treating arteriosclerosis.
Glioblastoma is the most common and aggressive brain tumor, affecting around 500 people in Sweden each year. The prognosis for patients is bleak, with an average survival time of about one year. This cancer is notoriously hard to treat due to several factors: it invades nearby healthy brain tissue, disables immune system responses, and presents challenges for drug delivery because of the blood-brain barrier, a protective membrane that limits substances from entering the brain.
In recent years, cancer research has increasingly focused on the tumor microenvironment, especially its interaction with immune cells. This study is the first to identify foam cells within the tumors of glioblastoma patients, revealing their role in promoting the disease.
Dr. Valeria Governa, a postdoctoral researcher at Lund University and the study’s first author, explains, “When tumor cells die and decompose, macrophages—a type of immune cell—come to clear away fat residues and other cellular debris. As these macrophages absorb fat, they transform into foam cells, a newly identified type of immune cell involved in cancer.”
Under a microscope, foam cells appear with a foamy or bubbly texture due to being filled with fat droplets. While their normal role is to clean up cellular waste, foam cells can sometimes become overloaded. In conditions like arteriosclerosis, they contribute to disease progression rather than resolution.
When foam cells are present in a tumor environment, they release signaling molecules that make the tumor more aggressive. These signals suppress immune responses and encourage the formation of blood vessels that supply nutrients to the tumor, fostering its growth and spread. Professor Mattias Belting, an oncologist at Lund University and Skåne University Hospital who led the research, underscores the significance of these findings: “We are the first to show how these foam cells operate within tumors in tissue samples from glioblastoma patients. This discovery is essential for understanding the tumor biology of glioblastoma and how a diseased environment manipulates immune cells, turning them into contributors to the cancer.”
Following this discovery, the researchers tested a drug originally designed to treat arteriosclerosis. This drug targets foam cells’ fat absorption processes, reducing their ability to stimulate tumor growth. By curbing their fat intake, the drug essentially “deactivates” foam cells within the tumor environment, weakening their influence on tumor progression.
The significance of this breakthrough extends beyond glioblastoma. Similar metabolic changes in immune cells drive a range of diseases, and foam cells have also been implicated in conditions like arteriosclerosis, neurodegenerative diseases, and certain infections.
“This discovery opens a path to potentially new therapies for glioblastoma, which we are eager to continue investigating,” concludes Professor Belting. The team’s work suggests a novel strategy to disrupt glioblastoma progression by targeting foam cells, representing a promising direction for future research into this and potentially other serious diseases.
Source: Lund University