Development of an in vivo system to model breast cancer metastatic organotropism and evaluate treatment response using the chick embryo

Solid stress compression enhances breast cancer cell migration through the upregulation of Interleukin-6

Apart from biochemical signals, tumour cells respond to biophysical and mechanical cues from their environment. The mechanical forces from the tumour microenvironment could be in the form of shear stress, tension, or solid stress compression. In this study, we explore the effects of solid stress compression on tumour cells. Solid stress compression, a prevalent biomechanical stimulus accumulated during tumour growth, has been shown to enhance invasive and metastatic phenotypes in cancer cells. However, the underlying molecular mechanism that elicits this aggressive metastatic phenotype, especially in breast cancer, is not extensively studied. Using an established 2D in vitro setup to apply incremental solid stress compression, we found that migratory and invasive capacities of aggressive breast cancer cells were enhanced in a biphasic manner. We also found that the transcript and protein levels of Interleukin-6 (IL-6) and SNAI1 were upregulated in response to solid stress. The resultant increased secretion of IL-6 could in turn lead to autocrine activation of downstream signalling pathways and impact on cancer cell migration and invasion.

Radiotherapy in Preclinical Models of Brain Metastases: A Review and Recommendations for Future Studies

Brain metastases (BMs) frequently occur in primary tumors such as lung cancer, breast cancer, and melanoma, and are associated with notably short natural survival. In addition to surgical interventions, chemotherapy, targeted therapy, and immunotherapy, radiotherapy (RT) is a crucial treatment for BM and encompasses whole-brain radiotherapy (WBRT) and stereotactic radiosurgery (SRS). Validating the efficacy and safety of treatment regimens through preclinical models is imperative for successful translation to clinical application. This not only advances fundamental research but also forms the theoretical foundation for clinical study. This review, grounded in animal models of brain metastases (AM-BM), explores the theoretical underpinnings and practical applications of radiotherapy in combination with chemotherapy, targeted therapy, immunotherapy, and emerging technologies such as nanomaterials and oxygen-containing microbubbles. Initially, we provided a concise overview of the establishment of AM-BMs. Subsequently, we summarize key RT parameters (RT mode, dose, fraction, dose rate) and their corresponding effects in AM-BMs. Finally, we present a comprehensive analysis of the current research status and future directions for combination therapy based on RT. In summary, there is presently no standardized regimen for AM-BM treatment involving RT. Further research is essential to deepen our understanding of the relationships between various parameters and their respective effects.