The combined use of radiation therapy and chemotherapy is commonly being used in cancer treatment. The side effects of the treatment can be further minimized through targeted delivery of anticancer drugs and local enhancement of the radiation dose. Gold nanoparticles (GNPs) can play a significant role in this regard since GNPs can be used as radiation dose enhancers and anticancer drug carriers. Anticancer drug, bleomycin, was chosen as the model drug, since it could be easily conjugated onto GNPs through the gold–thiol bond. Gold nanoparticles of size 10 nm were synthesized using the citrate reduction method. The surface of The GNPs was modified with a peptide sequence (CKKKKKKGGRGDMFG) containing the RGD domain and anticancer drug, bleomycin. Human breast cancer cells (MDA-MB-231) were incubated with 0.3 nM concentration of GNP–drug complex for 16 h prior to irradiation with a 2 Gy single fraction of 6 MV X-rays. After the treatment, cells were trypsinized and seeded in 60 mm dishes for clonogenic assay. Damage to DNA was probed using immunofluorescence assay. Cancer cells internalized with the GNP–drug complex had a 32 ± 9% decrease in cell survival and statistically significant enhancement in DNA (deoxyribonucleic acid) damage as compared to control cells (irradiated with no GNPs) after receiving a radiation dose of 2 Gy with 6 MV photons. The experimental results demonstrate that GNP-mediated chemoradiation has the potential to improve cancer care in the near future through enhancement of the local radiation dose and controlled delivery of anticancer drugs.

中文翻译：

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金纳米粒子介导的联合癌症治疗

放射疗法和化学疗法的联合使用通常用于癌症治疗。通过靶向递送抗癌药和局部增加放射剂量，可以进一步将治疗的副作用最小化。金纳米颗粒（GNP）在这方面可以发挥重要作用，因为GNP可以用作辐射剂量增强剂和抗癌药物载体。选择抗癌药博来霉素作为模型药物，因为它可以通过金-硫醇键轻松结合到GNP上。使用柠檬酸盐还原法合成了大小为10 nm的金纳米颗粒。用含有RGD结构域和抗癌药博来霉素的肽序列（CKKKKKKGGRGDMFG）修饰GNP的表面。将人乳腺癌细胞（MDA-MB-231）与0孵育。在用2 Gy的6 MV X射线单次照射之前16 h，GNP-药物复合物的浓度为3 nM。处理后，将细胞用胰蛋白酶消化，并接种在60 mm皿中以进行克隆形成测定。使用免疫荧光分析探测对DNA的损伤。与对照组细胞（无GNP照射）相比，接受GNP-药物复合物内化的癌细胞的存活率降低了32±9％，DNA（脱氧核糖核酸）损伤的统计学上显着增强。 6 MV光子。实验结果表明，GNP介导的化学放射通过提高局部放射剂量和控制抗癌药物的输送，在不久的将来具有改善癌症护理的潜力。