Triple-negative breast cancers are extremely aggressive with limited treatment options because of the reduced response of the cancerous cells to hormonal therapy. Here, monodispersed zinc-containing mesoporous silica nanoparticles (MSNPs-Zn) were produced as a tuneable biodegradable platform for delivery of therapeutic zinc ions into cells. We demonstrate that the nanoparticles were internalized by cells, and a therapeutic dose window was identified in which the MSNPs-Zn were toxic to breast cancer cells but not to healthy epithelial (MCF-10a) cells or to murine macrophages. A significant reduction in the viability of triple negative MDA-MB-231 and MCF-7 (ER+) breast cancer cells was seen following 24 h exposure to MSNPs-Zn. The more aggressive MDA-MB-231 cells, with higher metastatic potential, were more sensitive to MSNPs-Zn than the MCF-7 cells. MSNPs-Zn underwent biodegradation inside the cells, becoming hollow structures, as imaged by high-resolution transmission electron microscopy. The mesoporous silica nanoparticles provide a biodegradable vehicle for therapeutic ion release inside cells.

由于癌细胞对激素治疗的反应减少，三阴性乳腺癌极具侵略性，治疗选择有限。在这里，单分散的含锌介孔二氧化硅纳米粒子（MSNPs-Zn）被生产为可调节的可生物降解的平台，用于将治疗性锌离子输送到细胞中。我们证明纳米粒子被细胞内在化，并确定了治疗剂量窗，其中MSNPs-Zn对乳腺癌细胞有毒，但对健康上皮（MCF-10a）细胞或鼠巨噬细胞无毒。暴露于MSNPs-Zn 24小时后，发现三阴性MDA-MB-231和MCF-7（ER +）乳腺癌细胞的活力显着降低。具有更高转移潜力的更具侵略性的MDA-MB-231细胞比MCF-7细胞对MSNPs-Zn更为敏感。MSNPs-Zn在细胞内部经历了生物降解，变成了空心结构，如高分辨率透射电子显微镜所成像。中孔二氧化硅纳米颗粒提供了可生物降解的载体，用于治疗性离子在细胞内释放。