Aurora-A/STK15/BTAK overexpression induces centrosome amplification, chromosomal instability, and transformation in human urothelial cells

Aurora-A/STK15/BTAK kinase encoding gene, located on chromosome 20q13, is frequently amplified and overexpressed in human cancers. Sen et al. previously demonstrated that Aurora-A amplification and overexpression are associated with aneuploidy and clinically aggressive bladder cancer (J Natl Cancer Inst (2002) 94, 1320-1329). To examine if this association is the direct result of Aurora-A gene amplification and overexpression, an immortalized human urothelial cell line (SV-HUC) was infected with an adenoviral Aurora-A-green fluorescent protein (Ad-Aurora-A-GFP) fusion construct inducing ectopic expression of the resulting fusion protein. Controls included mock-infected and adenoviral-GFP infected cells. Ectopic expression of transduced Aurora-A did not alter the doubling time of the SV-HUC cells but significantly increased the number of cells with multiple centrosomes displaying aneuploidy and increased colony formation in soft agar. This is the first report demonstrating that overexpression of Aurora-A induces centrosome anomalies together with chromosomal instability and malignant transformation-associated phenotypic changes in immortalized human urothelial cells, thus supporting the hypothesis that this gene plays an important role in the development of aggressive bladder cancer

Scintillator ageing of the T2K near detectors from 2010 to 2021

The T2K experiment widely uses plastic scintillator as a target for neutrino interactions and an active medium for the measurement of charged particles produced in neutrino interactions at its near detector complex. Over 10 years of operation the measured light yield recorded by the scintillator based subsystems has been observed to degrade by 0.9–2.2% per year. Extrapolation of the degradation rate through to 2040 indicates the recorded light yield should remain above the lower threshold used by the current reconstruction algorithms for all subsystems. This will allow the near detectors to continue contributing to important physics measurements during the T2K-II and Hyper-Kamiokande eras. Additionally, work to disentangle the degradation of the plastic scintillator and wavelength shifting fibres shows that the reduction in light yield can be attributed to the ageing of the plastic scintillator. The long component of the attenuation length of the wavelength shifting fibres was observed to degrade by 1.3–5.4% per year, while the short component of the attenuation length did not show any conclusive degradation