Zinc‐doped hydroxyapatite (HA) nanoparticles were synthesized by microwave assisted method and used with ionizing radiation for inhibition of proliferation of breast cancer cells. Zinc‐doped HAs were produced in four different compositions in order to determine the best doping rate in terms of physical and biological properties. Nanoparticle characterizations were performed with X‐ray diffractometer, Fourier transform infrared spectroscopy, scanning electron microscopy, and inductively coupled plasma‐mass spectrometry. Viability of MDA‐MB‐231(isolated at M D Anderson from a pleural effusion of a patient with invasive ductal carcinoma) cells treated with nano‐HA particles and radiation were assessed by MTT assay. Caspase‐7 and Poly (ADP‐ribose) polymerase protein expressions in samples were examined by the Western blot. X‐ray diffraction patterns of our samples were found to be in good correlation with the reference HA peaks. Notably, increasing zinc amount resulted in elevated percentage of β‐tricalcium phosphate, phases. All formulations including pure HA particles were non‐cytotoxic in MDA MB 231 cells. On the other hand, low rate Zn‐doped HA particles showed significant anti‐proliferation effect during irradiation. The combination of irradiation with Zn‐doped HA particles also induced apoptosis, demonstrated as cleavage of caspase‐7 and PARP proteins. In conclusion, low rate Zn‐doped HA enhanced the radiation effect on breast cancer cells.

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锌掺杂羟基磷灰石纳米粒子对乳腺癌细胞的放射增敏作用

通过微波辅助方法合成了掺杂锌的羟基磷灰石（HA）纳米粒子，并将其与电离辐射一起用于抑制乳腺癌细胞的增殖。以四种不同的成分生产了锌掺杂的HA，以便根据物理和生物学特性确定最佳的掺杂速率。使用X射线衍射仪，傅立叶变换红外光谱仪，扫描电子显微镜和电感耦合等离子体质谱仪对纳米颗粒进行表征。通过MTT分析评估了用nano-HA颗粒和放射治疗的MDA-MB-231细胞（在侵袭性导管癌患者的胸腔积液处MD安德森分离）的生存能力。通过蛋白质印迹法检测样品中的Caspase-7和聚（ADP-核糖）聚合酶蛋白表达。发现我们样品的X射线衍射图与参考HA峰具有良好的相关性。值得注意的是，锌含量的增加导致β-磷酸三钙相的百分比增加。包括纯HA颗粒在内的所有制剂在MDA MB 231细胞中均无细胞毒性。另一方面，低剂量的Zn掺杂HA颗粒在辐照过程中表现出显着的抗扩散作用。Zn掺杂的HA颗粒的辐照组合也诱导了细胞凋亡，表现为caspase-7和PARP蛋白的裂解。总之，低剂量的Zn掺杂的HA增强了对乳腺癌细胞的辐射作用。包括纯HA颗粒在内的所有制剂在MDA MB 231细胞中均无细胞毒性。另一方面，低剂量的Zn掺杂HA颗粒在辐照过程中表现出显着的抗扩散作用。Zn掺杂的HA颗粒的辐照组合也诱导了细胞凋亡，表现为caspase-7和PARP蛋白的裂解。总之，低剂量的Zn掺杂的HA增强了对乳腺癌细胞的辐射作用。包括纯HA颗粒在内的所有制剂在MDA MB 231细胞中均无细胞毒性。另一方面，低剂量的Zn掺杂HA颗粒在辐照过程中表现出显着的抗扩散作用。Zn掺杂的HA颗粒的辐照组合也诱导了细胞凋亡，表现为caspase-7和PARP蛋白的裂解。总之，低剂量的Zn掺杂的HA增强了对乳腺癌细胞的辐射作用。