Researchers at Northwestern Medicine Canning Thoracic Institute have identified a surprising link between COVID-19 infection and cancer regression. Their study, published in The Journal of Clinical Investigation, demonstrates that the SARS-CoV-2 virus can trigger the development of specialized immune cells with anti-cancer properties, offering a potential new approach for treating cancers resistant to conventional therapies.
Inducible Nonclassical Monocytes (I-NCMs) and Cancer Cell Attack
The study focused on inducible nonclassical monocytes (I-NCMs), a unique type of immune cell activated during severe COVID-19. These cells possess the ability to infiltrate tumor sites and recruit natural killer cells, which then directly attack cancer cells, leading to tumor shrinkage. According to Dr. Ankit Bharat, chief of thoracic surgery at the Canning Thoracic Institute and senior author of the study, "This discovery opens up a new avenue for cancer treatment." The researchers observed a response in melanoma, lung, breast, and colon cancer models.
Mechanism of Action: CCR2 Receptor and Tumor Infiltration
Unlike typical non-classical monocytes, I-NCMs retain a specific receptor called CCR2. This receptor allows them to move beyond blood vessels and infiltrate the tumor environment. "What makes these cells so special is their dual capability," Dr. Bharat explained. "In contrast, the I-NCMs created during severe Covid-19 retain a unique receptor called CCR2, allowing them to travel beyond blood vessels and infiltrate the tumor environment. Once there, they release certain chemicals to recruit body’s natural killer cells...helping to shrink the tumor."
Preclinical Evidence and Future Directions
The findings, while currently based on animal and human tissue studies, offer hope for patients with advanced cancers that have not responded to other treatments. The researchers suggest that I-NCMs could be further developed using small molecules, potentially creating a new therapeutic path. The study was funded by the National Institutes of Health. The next step involves clinical trials to assess the safety and efficacy of this approach in humans. Lung cancer accounts for the majority of the estimated 611,720 cancer deaths in the U.S. this year.
