14-3-3 proteins have important roles in several cellular processes such as cell cycle progression, the DNA-damage checkpoint and apoptosis. We have shown previously that depleting 14-3-3η, a 14-3-3 isoform, enhances mitotic cell death, and that combining it with microtubule agents is more effective for anticancer therapeutics. In this study, we investigated whether depleting 14-3-3η can be combined with radiotherapy to enhance its therapeutic efficacy. We found that depleting 14-3-3η resulted in a synergistic radiosensitizing effect when combined with radiotherapy in several glioblastoma cell lines, where its specific expression and correlation of its expression level with malignancy have been reported. The radiosensitizing effect was associated with enhanced mitotic cell death by 14-3-3η depletion but not with mitotic catastrophe, which is one of the major cell death mechanisms observed in response to irradiation of most solid tumors. These results suggest that 14-3-3η may be a therapeutic target to overcome radioresistance in glioblastoma.

This study evaluated the structural changes in the reproductive tract of Asiatic black bears using serial transrectal ultrasonography. In addition, the ultrasonographic observations were compared with the results of vaginal cytology and hormonal analyses. The collection of blood for hormonal analysis, vaginal cytology and transrectal ultrasonography was performed in two bears (Bears 1 and 2) from June 2011 to August 2013 without mating and in a third bear (Bear 3) from April to December 2012, allowing natural mating. Serial ultrasonographic observations showed cyclic changes in ovarian structures (e.g. emergence of small follicles, growth and ovulation of dominant follicles and corpus luteum (CL) formation) during the reproductive cycles of the three bears. The diameter of the uterine horns remained similar throughout the reproductive cycle in Bears 1 and 2, and it remained similar from April until October, but an enlargement containing foetuses was observed in Bear 3 in December. The ultrasonographic observations were consistent with the data obtained through vaginal cytology and progesterone analysis during the reproductive cycle. An average of 4.0 (±0.4) dominant follicles was observed during the oestrous stage (May-August), during which the superficial cells accounted for >90% of the total vaginal cells. In addition, the detection of an average of 2.6 (±0.2) CL was associated with increased plasma progesterone concentrations (3.0 ± 0.4 ng/ml) between June and December (near hibernation). In conclusion, serial transrectal ultrasonography demonstrated yearly oestrous (ovulation) cycles via follicular dynamics and CL formation on ovaries, accordingly with vaginal cytology and hormonal level in the Asiatic black bear.