NEW DELHI– Common respiratory viruses such as Covid-19 and influenza may trigger the reactivation of dormant breast cancer cells in the lungs, potentially leading to new metastatic tumors, according to a new study published in Nature.
Researchers from the Albert Einstein College of Medicine in the U.S. and Utrecht University in the Netherlands found that these infections can “wake up” disseminated cancer cells (DCCs) — cells that have spread from a primary tumor and lie dormant in distant organs for extended periods.
“Our findings indicate that individuals with a history of cancer may benefit from taking precautions against respiratory viruses, such as vaccination when available, and discussing any concerns with their health care providers,” said study co-author Julio Aguirre-Ghiso.
The team’s mouse experiments showed that exposure to SARS-CoV-2 or influenza led to a rapid activation of dormant DCCs in the lungs. Within days, metastatic cells multiplied, and by two weeks, visible lung tumors appeared.
Molecular analysis pointed to interleukin-6 (IL-6) — an inflammatory protein released during infections — as the key driver behind this reactivation. The study suggests that IL-6 inhibitors or other targeted immunotherapies could potentially prevent or slow down metastatic relapse.
To validate the findings in humans, researchers analyzed two large patient databases and discovered that cancer survivors who contracted respiratory infections had a higher risk of metastasis, particularly within the first year post-infection.
“The effect was most pronounced in the first year after infection,” said co-author Roel Vermeulen. “It mirrors the rapid progression we saw in animal models.”
Vermeulen emphasized that the study’s data came from the pre-Covid vaccine era. “Our findings suggest that cancer survivors may be at increased risk of metastatic relapse after common respiratory viral infections,” he said. (Source: IANS)
