RESUMO
Cell proliferation was inhibited following forced over-expression of miR-30a in the ovary cancer cell line A2780DX5 and the gastric cancer cell line SGC7901R. Interestingly, miR-30a targets the DNA replication protein RPA1, hinders the replication of DNA and induces DNA fragmentation. Furthermore, ataxia telangiectasia mutated (ATM) and checkpoint kinase 2 (CHK2) were phosphorylated after DNA damage, which induced p53 expression, thus triggering the S-phase checkpoint, arresting cell cycle progression and ultimately initiating cancer cell apoptosis. Therefore, forced miR-30a over-expression in cancer cells can be a potential way to inhibit tumour development.
Assuntos
Proliferação de Células/fisiologia , Replicação do DNA/fisiologia , MicroRNAs/fisiologia , Proteína de Replicação A/metabolismo , Apoptose/genética , Apoptose/fisiologia , Proteínas Mutadas de Ataxia Telangiectasia/genética , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Ciclo Celular/genética , Ciclo Celular/fisiologia , Linhagem Celular Tumoral , Proliferação de Células/genética , Senescência Celular/genética , Senescência Celular/fisiologia , Quinase do Ponto de Checagem 2/genética , Quinase do Ponto de Checagem 2/metabolismo , Ensaio Cometa , Replicação do DNA/genética , Histonas/metabolismo , Humanos , Imuno-Histoquímica , MicroRNAs/genética , MicroRNAs/metabolismo , Interferência de RNA/fisiologia , Proteína de Replicação A/genéticaRESUMO
A double-strip array-based metasurface that supports the sharp quasi-bound states in the continuum (quasi-BICs) is demonstrated in terahertz regions. By tuning the structural parameters of metal strips, the conversion of BICs and quasi-BICs is controllable. The simulated results exhibit an achieved maximum Q-factor for quasi-BICs that exceeds 500, corresponding to a bandwidth that is less than 1 GHz. The optical response of quasi-BICs is mainly affected by the properties of substrates. Resonant frequencies decrease linearly with increasing refractive index. The bandwidth of quasi-BICs decreases to 0.9 GHz when n is 2.2. The sharp quasi-BICs are also sensitive to changes in material absorption. Low-loss materials show higher Q-factors. Thus, the selection of a suitable substrate material will be beneficial in achieving resonance with a high Q value. The sensitivity of DSAs for molecules is assessed using a thin membrane layer. The DSAs show high sensitivity, which achieves a frequency shift of 70 GHz when the thickness of the membrane is 10 µm, corresponding to a sensitivity of 87.5 GHz/RIU. This metasurface with sharp quasi-BICs is expected to perform well in THz sensing.