New research from Princeton University uncovers why bone metastasis often leads to anemia

Cancer specialists have long known that anemia, caused by a lack of healthy red blood cells, often arises when cancer metastasizes to the bone, but it’s been unclear why. Now, a research team led by Princeton University researchers Yibin Kang and Yujiao Han has uncovered exactly how this happens in metastatic breast cancer, and it involves a type of cellular hijacking. The discovery aims to help slow down bone metastasis – one of cancer’s deadliest forms.

In a study forthcoming in the journal Cell on September 3, Kang and Han reveal that cancer cells effectively commandeer a specialized cell that normally recycles iron in the bone, known as an erythroblast island (EBI) macrophage. This both deprives red blood cells of necessary iron and helps the tumor continue to grow in the bone. What’s more, when the tumor takes up the iron from the macrophage, it starts to behave as if it’s the normal recipient – a red blood cell – producing hemoglobin and helping the tumor survive in the bone’s hostile oxygen-deficient environment. 

Understanding metastatic cancer – or cancer that grows and spreads in other parts of the body beyond the original tumor site – is critically important. It is one of the deadliest forms of cancer and there is no cure. Of patients who die from breast and prostate cancer, 70% have bone metastasis. 

For the past two decades, Kang and much of the cancer biology field, have focused on studying the tumor cells. With the advent of single-cell sequencing and advanced cell labeling technologies, now Kang has shifted to studying the surrounding environment that nurtures or restrains the cancer, moving from investigating the ‘seeds’ to the ‘soil.’ Although the current study focuses on metastatic breast cancer, the findings have been extended to other major cancer types and carry broad implications. By revealing how tumors manipulate their surroundings, the work opens new avenues for therapies designed to slow or stop bone metastasis and relieve the debilitating anemia that often comes with it.

 

Small fold – big role: A tissue fold known as the cephalic furrow, an evolutionary novelty that forms between the head and the trunk of fly embryos, plays a mechanical role in stabilizing embryonic tissues during the development of the fruit fly Drosophila melanogaster.

Combining theory and experiment: Researchers integrated computer simulations with their experiments and showed that the timing and position of cephalic furrow formation are crucial for its function, preventing mechanical instabilities in the embryonic tissues.

Evolutionary response to mechanical stress: The increased mechanical instability caused by embryonic tissue movements may have contributed to the origin and evolution of the cephalic furrow genetic program. This shows that mechanical forces can shape the evolution of new developmental features.

Researchers at Aarhus University used laser speckle contrast imaging to study vasomotion—the rhythmic pulsing of small brain vessels—in awake mice. By combining high-resolution imaging with advanced analysis, they showed that vasomotion arises from arterial walls in short bursts, lasting about 80 seconds, and then propagates as flowmotion downstream to veins with a measurable delay. The findings provide new evidence of how blood vessels coordinate brain perfusion and highlight methods for studying vascular dynamics relevant to neurodegenerative and cerebrovascular disease.

Biological condensates are small, membraneless organelles typically consisting of multiple proteins and nucleic acids within cells. They are involved in a diverse array of cellular processes but, despite their importance, methods to quantify their molecular makeup are lacking. In a groundbreaking publication, researchers from the Brugués group at the Cluster of Excellence Physics of Life at Dresden University of Technology, the Leibniz Institute of Polymer Research Dresden, and the Max Planck Institute of Molecular Cell Biology and Genetics reveal a new experimental method to infer the composition of condensates reconstituted from complex mixtures.

Polyamines are natural molecules that promote healthy aging but are also linked to cancer progression, presenting a long-standing puzzle in biomedical research. In a recent study, researchers from Japan explored how polyamines affect cancer cells, uncovering a key interaction with protein eIF5A2. Their findings reveal that polyamines drive cancer growth by altering ribosomal gene expression, offering a potential target for selective cancer therapies and shedding light on the risks of polyamines.