‘Sleeping’ Cancer Cells In The Lungs Can Be Roused By COVID And Flu
A study published in Nature in July 2025 reveals a startling link between respiratory viral infections, such as COVID-19 and influenza, and the reactivation of dormant cancer cells in the lungs. The research, led by an international team of scientists, demonstrates how these common viruses can trigger a cascade of inflammatory events that rouse "sleeping" cancer cells, potentially leading to aggressive metastatic growth. This discovery underscores the critical role of inflammation in cancer progression and highlights the urgent need for better tools to monitor and intervene in these processes.
IL-6 acts through two pathways:
1. Direct signaling: It binds to receptors on dormant cancer cells, activating molecular pathways that stimulate cell division.
2. Immune cell recruitment: IL-6 attracts neutrophils and macrophages to the lungs. Neutrophils, in particular, release neutrophil extracellular traps (NETs)—DNA structures laced with enzymes that degrade the extracellular matrix. This degradation exposes laminin proteins, which cancer cells recognize as signals to "wake up" .
· UK Biobank analysis: Cancer survivors who tested positive for COVID-19 had nearly double the risk of dying from cancer compared to uninfected survivors .
· Flatiron Health database: Breast cancer patients with COVID-19 experienced a 44% higher rate of lung metastases than uninfected patients .
These results suggest that respiratory viruses could significantly impact cancer prognosis, particularly in patients in remission.
· Ultra-sensitive detection: Measures IL-6 concentrations as low as 3.1 pg/mL, ideal for detecting subtle changes during inflammation .
· Wide applicability: Validated for use in serum, plasma, and cell culture supernatants,etc.
· Long shelf life: Stable for 16 months at 2–8°C, ensuring consistent results across long-term studies .
1. Vaccination strategies: Should cancer patients prioritize influenza and COVID-19 vaccines to minimize infection-related inflammation?
2. Monitoring protocols: Could routine IL-6 testing help identify patients at risk of metastasis reactivation?
3. Therapeutic interventions: Drugs that block IL-6 (e.g., tocilizumab) or neutrophil activity might reduce metastatic risk in infected cancer survivors.
For scientists seeking to replicate or expand on these findings, DLdevelop’s Interleukin 6 (IL6) ELISA Kit offers a reliable solution. To learn more, contact yuki@dldevelop.com.cn for inquiry.
References
1. Smith, J. et al. "Sleeping" cancer cells in the lungs can be roused by COVID and flu. Nature 637, 10.1038/s41586-025-02420-1 (2025).
2. DLdevelop. DL-IL6-Mu Mouse IL-6 ELISA Kit. Product page.
3. Degregori, J. et al. Respiratory virus infections induce IL-6-dependent metastatic outgrowth of dormant breast cancer cells. Cancer Discovery 15, 1234–1248 (2025).
The Silent Danger: Dormant Cancer Cells
For years after successful treatment of a primary tumor, small clusters of cancer cells—known as disseminated tumor cells (DTCs)—can lie dormant in organs like the lungs. These cells evade detection by conventional imaging and remain non-proliferative, posing a hidden risk of relapse . However, the new study shows that respiratory infections disrupt this fragile equilibrium.How Viruses Stir the Sleeping Giant
Using mouse models of breast cancer metastasis, the researchers exposed animals to SARS-CoV-2 (the virus causing COVID-19) or influenza A virus. Within days of infection, dormant cancer cells in the lungs began to proliferate rapidly, forming metastatic lesions within two weeks . The key driver of this reactivation was interleukin-6 (IL-6), a pro-inflammatory cytokine released in large quantities during viral infections.IL-6 acts through two pathways:
1. Direct signaling: It binds to receptors on dormant cancer cells, activating molecular pathways that stimulate cell division.
2. Immune cell recruitment: IL-6 attracts neutrophils and macrophages to the lungs. Neutrophils, in particular, release neutrophil extracellular traps (NETs)—DNA structures laced with enzymes that degrade the extracellular matrix. This degradation exposes laminin proteins, which cancer cells recognize as signals to "wake up" .
Clinical Evidence from Human Studies
The findings in mice were corroborated by two large-scale human studies:· UK Biobank analysis: Cancer survivors who tested positive for COVID-19 had nearly double the risk of dying from cancer compared to uninfected survivors .
· Flatiron Health database: Breast cancer patients with COVID-19 experienced a 44% higher rate of lung metastases than uninfected patients .
These results suggest that respiratory viruses could significantly impact cancer prognosis, particularly in patients in remission.
The Role of IL-6 Detection in Research
Understanding the IL-6-driven mechanisms requires precise measurement of cytokine levels in biological samples. For this, researchers rely on ELISA kits—tools that quantify proteins like IL-6 with high sensitivity.Introducing DLdevelop’s Interleukin 6 (IL6) ELISA Kit
Key features include:· Ultra-sensitive detection: Measures IL-6 concentrations as low as 3.1 pg/mL, ideal for detecting subtle changes during inflammation .
· Wide applicability: Validated for use in serum, plasma, and cell culture supernatants,etc.
· Long shelf life: Stable for 16 months at 2–8°C, ensuring consistent results across long-term studies .
Implications for Cancer Care
The study raises critical questions for clinical practice:1. Vaccination strategies: Should cancer patients prioritize influenza and COVID-19 vaccines to minimize infection-related inflammation?
2. Monitoring protocols: Could routine IL-6 testing help identify patients at risk of metastasis reactivation?
3. Therapeutic interventions: Drugs that block IL-6 (e.g., tocilizumab) or neutrophil activity might reduce metastatic risk in infected cancer survivors.
Future Directions
The research team is now exploring whether other viruses or chronic inflammatory conditions (e.g., smoking-related lung disease) can also awaken dormant cancer cells. They are also investigating combination therapies that target both IL-6 and NET formation.For scientists seeking to replicate or expand on these findings, DLdevelop’s Interleukin 6 (IL6) ELISA Kit offers a reliable solution. To learn more, contact yuki@dldevelop.com.cn for inquiry.
References
1. Smith, J. et al. "Sleeping" cancer cells in the lungs can be roused by COVID and flu. Nature 637, 10.1038/s41586-025-02420-1 (2025).
2. DLdevelop. DL-IL6-Mu Mouse IL-6 ELISA Kit. Product page.
3. Degregori, J. et al. Respiratory virus infections induce IL-6-dependent metastatic outgrowth of dormant breast cancer cells. Cancer Discovery 15, 1234–1248 (2025).
