How Cancer Cells Work Together to Drive Breast Cancer Invasion Revealed

In a study published recently in Nature Materials, Stanford researchers report uncovering a novel physical mechanism employed by breast cancer cells to transition from non-invasive to invasive states. While the majority of breast cancers are initially treatable when confined to breast milk duct linings, invasive cancers pose significant challenges to treatment. The team, led by Ovijit Chaudhuri, challenged the conventional focus on chemical methods of breaking through the basement membrane and demonstrated that cancer cells collaborate in groups to physically deform and tear through this barrier.

Traditionally, the invasion process has been studied at the single-cell level. However, Chaudhuri's team revealed that invasion is a collective phenomenon, where groups of cells work in concert to penetrate the basement membrane. The researchers developed a three-dimensional hydrogel model mimicking breast tissue properties, enabling them to observe the mechanical forces involved.

Contrary to the prevailing paradigm that emphasized chemical degradation, the team discovered that cancer cells within the model collectively swelled, stretching the basement membrane like a balloon. This coordinated volume expansion weakened the membrane, allowing cancer cells to apply additional forces, opening holes and escaping. The findings were validated through computational modeling, confirming the role of physical forces in breaking through the basement membrane.

This discovery opens avenues for new therapeutic strategies to block invasion and provides insights into predicting which patients with pre-invasive breast cancer are more likely to experience cancer spread. The research marks a crucial step toward understanding the complex interplay between cancer cells and breast tissue, with ongoing investigations focusing on the post-invasion interactions and the mechanical and structural aspects of the basement membrane.