Abstract:
The circadian clock controls behavior and physiology. Presently, there is clear evidence of a connection between this timing system and cancer development/progression. Moreover, circadian rhythm consideration in the therapeutic action of anticancer drugs can enhance the effectiveness of cancer therapy. Nanosized drug delivery systems (DDS) have been demonstrated to be suitable engineered platforms for drug targeted/sustained release. The investigation of the chronobiology-nanotechnology relationship, i.e., timing DDS performance according to a patient\'s circadian rhythm, may greatly improve cancer clinical outcomes. In the present work, we synthesized nanosystems based on an octa-arginine (R8)-modified poly(amidoamine) dendrimer conjugated with the anticancer drug paclitaxel (PTX), G4-PTX-R8, and its physicochemical properties were revealed to be appropriate for in vitro delivery. The influence of the circadian rhythm on its cellular internalization efficiency and potential therapeutic effect on human cervical cancer cells (HeLa) was studied. Cell-internalized PTX and caspase activity, as a measure of induced apoptosis, were monitored for six time points. Higher levels of PTX and caspase-3/9 were detected at T8, suggesting that the internalization of G4-PTX-R8 into HeLa cells and apoptosis are time-specific/-regulated phenomena. For a deeper understanding, the clock protein Bmal1-the main regulator of rhythmic activity, was silenced by Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) technology. Bmal1 silencing was revealed to have an impact on both PTX release and caspase activity, evidencing a potential role for circadian rhythm on drug delivery/therapeutic effect mediated by G4-PTX-R8.
摘要:
昼夜节律时钟控制行为和生理学。目前,有明确的证据表明,这种计时系统与癌症发展/进展之间存在联系.此外,在抗癌药物的治疗作用中考虑昼夜节律可以提高癌症治疗的有效性。纳米药物递送系统(DDS)已被证明是用于药物靶向/持续释放的合适的工程化平台。对时间生物学与纳米技术关系的调查,即,根据患者的昼夜节律对DDS表现进行计时,可以大大改善癌症的临床结果。在目前的工作中,我们合成了基于八位精氨酸(R8)修饰的聚(酰胺胺)树枝状聚合物与抗癌药物紫杉醇(PTX)共轭的纳米系统,G4-PTX-R8及其物理化学性质被揭示为适合于体外递送。研究了昼夜节律对其细胞内化效率和对人宫颈癌细胞(HeLa)的潜在治疗作用的影响。细胞内化的PTX和半胱天冬酶活性,作为诱导细胞凋亡的量度,监测了六个时间点。在T8检测到更高水平的PTX和半胱天冬酶-3/9,表明G4-PTX-R8内化进入HeLa细胞和凋亡是时间特异性/调节的现象。为了更深入的了解,时钟蛋白Bmal1-节律活动的主要调节剂,通过成簇的定期间隔短回文重复(CRISPR)技术沉默。发现Bmal1沉默对PTX释放和半胱天冬酶活性都有影响,证明昼夜节律对G4-PTX-R8介导的药物递送/治疗效果的潜在作用。