Using a novel Cas9-based single-cell lineage tracing technique and RNA sequencing, a team from the University of California, San Francisco gain insights into the rates, routes, and drivers of metastasis. As reported in Science, the scientists applied their approach in a lung cancer xenograft mouse model and uncovered important aspects of metastatic biology over months of cancer cell growth and dissemination. These include a broad range of metastatic rates for different tumor populations, the pre-existence and stable heritability of these heterogeneous metastatic phenotypes, and the complex, multidirectional tissue routes by which cancer cells disseminate in this model. Beyond metastasis, the method "can inform many other facets of cancer biology like the timing or order of genetic mutations during malignant transformation [and] adaptation to different tumor microenvironments," the study's authors write. "Beyond cancer, our approach has the potential to empower the study of the phylogenetic foundations of biological processes that transpire over many cell generations at unprecedented resolution and scale." GenomeWeb has more on this, here.
A study of genetic data from people living in Eastern Europe in the Stone and Bronze Ages is reported in Science Advances this week, providing new details about the impact of the major population movements that occurred during these periods. A research group led by scientists from the University of Tartu analyzed DNA from the remains of 30 ancient individuals from sites in modern-day western Russia and Estonia, including three hunter-gatherers who lived around 10,800 BCE to 4250 BCE and 26 farmers who lived around 2900 BCE to 2050 BCE. The show that Eastern hunter-gatherer ancestry was present in northwestern Russia already from around 10,000 BCE and uncover an ancestry change that occurred with the arrival of farming, likely reflecting a rapid migration from somewhere near modern-day Ukraine.