CU Anschutz Researchers Discover Breast Cancer Cells Hijack Lung Repair Systems to Fuel Metastatic Growth

CU Anschutz researchers find breast cancer hijacks the lung's healing system. Repurposing the COPD drug Roflumilast may block this environment-driven tumor growth.

By: AXL Media

Published: Mar 26, 2026, 9:08 AM EDT

Source: Information for this report was sourced from University of Colorado Anschutz

The Biological Sabotage of Natural Pulmonary Healing

When breast cancer metastasizes to the lungs, it causes microscopic damage to the alveolar air sacs essential for respiratory function. Under normal circumstances, the lung initiates a rapid repair sequence to clear debris and rebuild tissue. However, new research from the CU Anschutz Cancer Center reveals that cancer cells have evolved to prolong this "repair mode," triggering a state of chronic inflammation. This biological sabotage turns a protective healing response into a supportive environment for malignancy. According to first author Jessica L. Christenson, PhD, the lung is simply performing its programmed duties, but the presence of cancer cells ensures that this repair signal is diverted to fuel tumor growth instead.

Alveolar Signaling and the Cycle of Tumor Expansion

The study highlights the role of specialized alveolar type II cells, which are responsible for lung tissue regeneration following an injury. In the presence of metastatic breast cancer, these cells are manipulated into releasing chemical signals that encourage tumor cells to proliferate. This creates a reciprocal signaling loop where cancer cells activate the lung's epithelial cells, which in turn release substances that act as fuel for the tumor. This interaction allows the cancer to expand far more aggressively than it would in a healthy, non-injured environment, effectively turning the lung's own cellular architecture against the patient.

Roflumilast: Repurposing a COPD Medication for Oncology

In a promising turn for clinical application, the research team tested the effects of Roflumilast, an anti-inflammatory drug currently approved for treating Chronic Obstructive Pulmonary Disease (COPD). In mouse models of metastatic breast cancer, the drug successfully slowed the outgrowth of tumors and reduced their overall size in the lungs. Crucially, Roflumilast does not work by killing the cancer cells directly; instead, it prevents the lung environment from becoming a hospitable "niche" for the tumors to thrive. This strategy represents a shift in focus from targeting the seed—the cancer cell—to targeting the soil—the pulmonary environment.