DNA reorganization drives breast cancer forward
Cancer is not only a disease of faulty genes. It is also a disease of a rearranged genome. New research reveals how the three-dimensional structure of DNA shifts as breast cancer develops.
Researchers used a high-resolution technique called Micro-C to map how DNA is folded and organized inside cells. They tracked these changes across a cell model of breast cancer progression, from normal cells through to metastatic cancer cells. The study was published in eLife.
The findings reveal a clear pattern. Large-scale shifts in the spatial organization of the genome (chromatin compartments) occur predominantly in the early stages of cancer development. More fine-grained structural changes, including shifts in topologically associating domains and DNA loop structures, accumulate later during the transition to metastasis.
Structure and gene expression are linked
Many genes that are differentially active in cancer cells appear to be physically connected to distant regulatory elements called enhancers. These connections are not random: they seem to contribute to increased or reduced gene activity. The relationship is not straightforward, however. Strong changes in loop structures occurred relatively rarely. The researchers conclude that shifts in chromatin contacts are not globally required for cancer progression, but may facilitate gene regulation at a specific subset of genes.
Relevance for aging research
The findings connect to a broader hypothesis in aging biology: as cells age or go awry, the organization of their genome changes. This can influence which genes are switched on or off, independently of changes in the DNA sequence itself. This field, called epigenomics, is central to current aging research. The new study contributes mechanistic detail to how genome structure supports cancer progression, though no direct therapeutic applications have yet emerged.
This is an observational study in a cell model, meaning findings cannot be directly translated to patients. It does, however, provide a detailed mechanistic picture of how structure and function converge during cancer transformation.