A team from Canada, Taiwan, and the US explore DNA methylation dynamics and related expression shifts in the brains of aging humans. Based on available DNA methylation data and array-based methylation profiling on post-mortem brain cortex tissue samples from identical or non-identical twins with Alzheimer's disease, the researchers saw signs of converging epigenetic and transcriptional patterns in individuals older than 75-years-old, particularly Alzheimer's-affected individuals. The study's authors attribute such features to "potential brain cell de-differentiation" with age, arguing that "epigenetic assimilation and tissue de-differentiation may help us better understand the molecular mechanisms of aging and the origins of diseases for which age is a risk factor."
The planarian Schmidtea mediterranea contains highly heterogeneous stem cells in its head, according to a study by researchers based at the University of Toronto and the Hospital for Sick Children. By doing single-cell RNA sequencing on transcripts from nearly 200 individual planarian stem cells and planarian head progeny cells over time, the team uncovered a population of proliferative stem cells that neighbor the planarian's brain. It also traced the activity of genes involved in cell lineage progression in the planarian, an organism known for its ability to regenerate robustly.
Researchers from Korea and the US present findings from single-cell RNA sequencing-based analysis of a renal cell carcinoma tumor and its matching lung metastasis. The team set out to uncover heterogeneity within and between the tumors by sequencing transcripts from more than 100 individual cells in samples from tumor samples and/or patient-derived xenograft samples from an individual with metastatic renal cell carcinoma. The analysis uncovered distinct potential treatment targets in the primary tumor and metastatic sample, while highlighting variability within each tumor, prompting the investigators to pursue a combinatorial treatment strategy that targeted two different pathways.