The accurate transition from G1 phase of the cell cycle to S phase is crucial for the control of eukaryotic cell proliferation, and its misregulation promotes oncogenesis. During G1 phase, growth-dependent cyclin-dependent kinase (CDK) activity promotes DNA replication and initiates G1-to-S phase transition. CDK activation initiates a positive feedback loop that further increases CDK activity, and this commits the cell to division by inducing genome-wide transcriptional changes. G1–S transcripts encode proteins that regulate downstream cell cycle events. Recent work is beginning to reveal the complex molecular mechanisms that control the temporal order of transcriptional activation and inactivation, determine distinct functional subgroups of genes and link cell cycle-dependent transcription to DNA replication stress in yeast and mammals.

The bone marrow usually works quietly in the background. It only comes into focus when something goes wrong, such as in blood cancers. In these cases, understanding exactly how blood production in our body works, and how this process fails, becomes critical.

Typically, bone marrow research relies heavily on animal models and oversimplified cell cultures in the laboratory. Now, researchers from the Department of Biomedicine at the University of Basel and University Hospital Basel have developed a realistic model of the bone marrow engineered entirely from human cells. This model may become a valuable tool not only for blood cancer research, but also for drug testing and potentially for personalized therapies, as reported by a team of researchers led by Professor Ivan Martin and Dr Andrés García García in the journal Cell Stem Cell.

Researchers are realistically recreating human bone marrow in the laboratory using artificial bone structures and human cells.

Through the actuation of vibronic modes in cell-membrane-associated aminocyanines, using near-infrared light, a distinct type of molecular mechanical action can be exploited to rapidly kill cells by necrosis. Vibronic-driven action (VDA) is distinct from both photodynamic therapy and photothermal therapy as its mechanical effect on the cell membrane is not abrogated by inhibitors of reactive oxygen species and it does not induce thermal killing. Subpicosecond concerted whole-molecule vibrations of VDA-induced mechanical disruption can be achieved using very low concentrations (500 nM) of aminocyanines or low doses of light (12 J cm^-2, 80 mW cm^-2 for 2.5 min), resulting in complete eradication of human melanoma cells in vitro. Also, 50% tumour-free efficacy in mouse models for melanoma was achieved. The molecules that destroy cell membranes through VDA have been termed molecular jackhammers because they undergo concerted whole-molecule vibrations. Given that a cell is unlikely to develop resistance to such molecular mechanical forces, molecular jackhammers present an alternative modality for inducing cancer cell death.

© 2023. The Author(s), under exclusive licence to Springer Nature Limited.

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New research finds that dying cells leave a “footprint of death” that guides immune responses — but viruses like influenza can exploit this signaling. The discovery, published in Nature Communications, offers new insight into cell death, viral transmission, and potential drug targets.

New insights into the aftermath of cell death might ultimately inform drug development.