Upregulation of microRNA-200a associates with tumor proliferation, CSCs phenotype and chemosensitivity in ovarian cancer

Ovarian cancer is a lethal gynecologic malignancy and always has a poor prognosis. Despite new treatments modalities, the long term outcomes had not been significantly improved in the past 30 years. Although microRNA-200a (miR-200a) has been reported to be a prognostic marker in ovarian cancer, it's exact role in ovarian cancer remain unclear. In this study, we inserted the response element of miR-200a in ovarian cancer cell line via lentivirus-mediated transgene in vitro, and qRT-PCR (real time quantitative reverse transcription PCR) assay confirmed that miR-200a was up regulated compared with control. Then colony-formation assay, cell cycle analysis, CCK8 assays in vitro and xenograft experiments in vivo were performed and verified that miR-200a promoted proliferation, while blocked the formation of tumor spheroids and reduced the ratio of SP (side population) cells in ovarian cancer. Finally, we invalidated that miR-200a significantly enhanced the chemosensitivity of paclitaxel but not cisplatin in both adherent culture and sphere culture. Taken together, we demonstrated that upregulation miR-200a promoted proliferation and inhibited CSCs phenotype in OVCAR-3 ovarian cancer cell line, combined with cell cycle-targeting drug paclitaxel could effectively eliminate the "side effects" of proliferation, and showed evidences that this strategy may be promising for ovarian cancer treatment.

A highly reversible Li–O2 battery utilizing a mixed electrolyte and a cathode incorporating Co3O4

Li–O₂ cell using a EMITFSI–DMSO electrolyte exhibited a low voltage gap and a long cycle life maintaining a satisfactory discharge capacity.

Measurements of ocean bottom low-angle backscattering by single-mode reverberation

The characteristics of scattering due to interface roughness are usually described by the backscattering matrix for reverberation modeling. The backscattering matrix based on the Bass perturbation theory has significant differences from that based on the empirical scattering rule (Lambert's rule), especially at low grazing angles. In a waveguide environment with a point source, it is very difficult to extract the quantitative characteristics of the backscattering matrix at low grazing angles from the experimental data because of the difficulties in acquiring low-grazing-angle scattering data and separating the scattering data between different modes (grazing angles). In contrast, the use of single-mode excitations as sources in shallow-water waveguides enables acquisition of good quality low-grazing-angle scattering data. In this paper, the characteristics of the backscattering matrix were obtained from different single-mode reverberation experiments in shallow-water. The experiments were carried out at different sites during different seasons off the coasts of China. Model-data comparisons were made and the results showed that at low grazing angles (2°-5°), the backscattering matrices based on the Bass perturbation theory were in good agreement with the experimental data, but the backscattering matrices based on Lambert's rule were not.

Epigenetics and evolution

Epigenetic mechanisms traditionally have been studied in the domains of development and disease, but they may also play important roles in ecological and evolutionary processes. In this article, we revisit historical as well as recent studies that indicate significant impacts of epigenetic processes on evolution. Our main focus is DNA methylation, which is a prevalent chemical modification of genomic DNA. First, it has been long known that DNA methylation acts as a major mutational facilitator in animal genomes and influences nucleotide compositions of genomes. More recently, genome-wide analyses have demonstrated that the current levels of DNA methylation can be predicted from the evolutionary signatures of DNA methylation, indicating that these two processes are intimately correlated. Indeed, the recent explosive growth in the knowledge of genomic DNA methylation in wide-ranging taxa has revealed that patterns of DNA methylation are surprisingly conserved across deep phylogenies. Interestingly, comparative analyses of humans and closely related primate species show that genomic regions that do show evolutionary divergence of DNA methylation are enriched for developmental and tissue specializations. A key question is how epigenetic patterns transmit between generations and impact evolutionary dynamics. On the one hand, some studies report direct transmissions of epigenetic features to the next generation. On the other hand, it is becoming clear that genomic sequence variants exist that encode and presumably regulate distinctive epigenetic patterns. For instance, numerous single-nucleotide polymorphisms that affect DNA-methylation patterns have been discovered in human populations. These studies begin to unveil a dynamic interplay between genomic and epigenomic factors across long and short evolutionary timescales.