Treatment of cancer has been limited by the poor efficacy and toxicity profiles of available drugs. There is a growing demand to develop alternative approaches to combat cancer such as use of nano-formulation-based drugs. Here, we report biosynthesis and characterization of silver nanoparticles (AgNPs) with papaya leaf extract (PLE) and its anti-cancer properties against different human cancer cells. Purified nanoparticles were characterized by standard techniques, such as TEM, STM, SEM, EDS, XRD, and FTIR. Furthermore, cytotoxic activity of AgNPs-PLE was carried out against different human cancer cells and non-tumorigenic human keratinocytes cells. AgNPs-PLE when compared with AgNPs-citric acid or PLE showed better efficacy against cancer cells and was also relatively less toxic to normal cells. Treatment of DU145 cells with AgNPs-PLE (0.5-5.0 μg/ml) for 24-48 h lowered total cell number by 24-36% (P < 0.05). Inhibition of cell growth was linked with arrest of cell cycle at G2/M phase at 24 h, while G1 and G2/M phase arrests at 48 h. ROS production was observed at earlier time points in presence of AgNPs-PLE, suggesting its role behind apoptosis in DU145 cells. Induction of apoptosis (57%) was revealed by AO/EB staining in DU145 cells along with induction of Bax, cleaved caspase-3, and cleaved PARP proteins. G1-S phase cell cycle check point marker, cyclin D1 was down-regulated along with an increase in cip1/p21 and kip1/p27 tumor suppressor proteins by AgNPs-PLE. These findings suggest the anti-cancer properties of AgNPs-PLE.

中文翻译：

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使用番木瓜叶提取物（AgNPs-PLE）合成的银纳米粒子会导致人前列腺（DU145）癌细胞的细胞周期阻滞和凋亡。

可用的药物不良的疗效和毒性特征限制了癌症的治疗。越来越需要开发替代方法来对抗癌症，例如使用基于纳米制剂的药物。在这里，我们报告木瓜叶提取物（PLE）的银纳米颗粒（AgNPs）的生物合成和表征，以及其对不同人类癌细胞的抗癌特性。纯化的纳米颗粒通过标准技术进行表征，例如TEM，STM，SEM，EDS，XRD和FTIR。此外，AgNPs-PLE对不同的人类癌细胞和非致瘤性人类角质形成细胞具有细胞毒活性。与AgNPs-柠檬酸或PLE相比，AgNPs-PLE对癌细胞具有更好的疗效，对正常细胞的毒性也相对较小。用AgNPs-PLE处理DU145细胞（0.5-5。0μg/ ml）持续24-48小时可使总细胞数降低24-36％（P <0.05）。细胞生长的抑制与细胞周期在24 h处在G2 / M期停滞有关，而G1和G2 / M期在48 h处停滞有关。在AgNPs-PLE存在的较早时间点观察到ROS的产生，表明其在DU145细胞凋亡中的作用。AO145 / EB染色在DU145细胞中诱导凋亡（57％），同时诱导Bax，裂解的caspase-3和裂解的PARP蛋白。AgNPs-PLE使G1-S期细胞周期检查点标志物cyclin D1下调，同时cip1 / p21和kip1 / p27肿瘤抑制蛋白增加。这些发现表明AgNPs-PLE的抗癌特性。而G1和G2 / M期则在48小时内停止。在AgNPs-PLE存在的较早时间点观察到ROS的产生，表明其在DU145细胞凋亡中的作用。AO145 / EB染色在DU145细胞中诱导凋亡（57％），同时诱导Bax，裂解的caspase-3和裂解的PARP蛋白。AgNPs-PLE使G1-S期细胞周期检查点标志物cyclin D1下调，同时cip1 / p21和kip1 / p27肿瘤抑制蛋白增加。这些发现表明AgNPs-PLE的抗癌特性。而G1和G2 / M期则在48小时内停止。在AgNPs-PLE存在的较早时间点观察到ROS的产生，表明其在DU145细胞凋亡中的作用。AO145 / EB染色在DU145细胞中诱导凋亡（57％），同时诱导Bax，裂解的caspase-3和裂解的PARP蛋白。AgNPs-PLE使G1-S期细胞周期检查点标志物cyclin D1下调，同时cip1 / p21和kip1 / p27肿瘤抑制蛋白增加。这些发现表明AgNPs-PLE的抗癌特性。AgNPs-PLE使G1-S期细胞周期检查点标志物cyclin D1下调，同时cip1 / p21和kip1 / p27肿瘤抑制蛋白增加。这些发现表明AgNPs-PLE的抗癌特性。AgNPs-PLE使G1-S期细胞周期检查点标志物cyclin D1下调，同时cip1 / p21和kip1 / p27肿瘤抑制蛋白增加。这些发现表明AgNPs-PLE的抗癌特性。