Dostalova Simona, Vasickova Katerina, Hynek David, Krizkova Sona, Richtera Lukas, Vaculovicova Marketa, Eckschlager Tomas, Stiborova Marie, Heger Zbynek, Adam Vojtech
Department of Chemistry and Biochemistry, Mendel University in Brno; Central European Institute of Technology, Brno University of Technology, Brno.
Department of Chemistry and Biochemistry, Mendel University in Brno.
Int J Nanomedicine. 2017 Mar 24;12:2265-2278. doi: 10.2147/IJN.S130267. eCollection 2017.
Due to many adverse effects of conventional chemotherapy, novel methods of targeting drugs to cancer cells are being investigated. Nanosize carriers are a suitable platform for this specific delivery. Herein, we evaluated the long-term stability of the naturally found protein nanocarrier apoferritin (Apo) with encapsulated doxorubicin (Dox). The encapsulation was performed using Apo's ability to disassemble reversibly into its subunits at low pH (2.7) and reassemble in neutral pH (7.2), physically entrapping drug molecules in its cavity (creating ApoDox). In this study, ApoDox was prepared in water and phosphate-buffered saline and stored for 12 weeks in various conditions (-20°C, 4°C, 20°C, and 37°C in dark, and 4°C and 20°C under ambient light). During storage, a very low amount of prematurely released drug molecules were detected (maximum of 7.5% for ApoDox prepared in PBS and 4.4% for ApoDox prepared in water). Fourier-transform infrared spectra revealed no significant differences in any of the samples after storage. Most of the ApoDox prepared in phosphate-buffered saline and ApoDox prepared in water and stored at -20°C formed very large aggregates (up to 487% of original size). Only ApoDox prepared in water and stored at 4°C showed no significant increase in size or shape. Although this storage caused slower internalization to LNCaP prostate cancer cells, ApoDox (2.5 μM of Dox) still retained its ability to inhibit completely the growth of 1.5×10 LNCaP cells after 72 hours. ApoDox stored at 20°C and 37°C in water was not able to deliver Dox inside the nucleus, and thus did not inhibit the growth of the LNCaP cells. Overall, our study demonstrates that ApoDox has very good stability over the course of 12 weeks when stored properly (at 4°C), and is thus suitable for use as a nanocarrier in the specific delivery of anticancer drugs to patients.
由于传统化疗存在许多不良反应，目前正在研究将药物靶向癌细胞的新方法。纳米级载体是实现这种特异性递送的合适平台。在此，我们评估了天然存在的蛋白质纳米载体脱铁铁蛋白（Apo）与包封的阿霉素（Dox）的长期稳定性。利用Apo在低pH（2.7）下可逆地分解成其亚基并在中性pH（7.2）下重新组装的能力进行包封，将药物分子物理包裹在其腔内（制备成ApoDox）。在本研究中，ApoDox在水和磷酸盐缓冲盐水中制备，并在各种条件下（-20°C、4°C、20°C以及黑暗中的37°C，以及环境光下的4°C和20°C）储存12周。在储存期间，检测到极少量过早释放的药物分子（在PBS中制备的ApoDox最多为7.5%，在水中制备的ApoDox为4.4%）。傅里叶变换红外光谱显示储存后任何样品均无显著差异。在磷酸盐缓冲盐水中制备的大多数ApoDox以及在水中制备并储存在-20°C的ApoDox形成了非常大的聚集体（高达原始尺寸的487%）。只有在水中制备并储存在4°C的ApoDox尺寸和形状没有显著增加。尽管这种储存导致其进入LNCaP前列腺癌细胞的内化速度减慢，但ApoDox（2.5μM的Dox）在72小时后仍保留完全抑制1.5×10个LNCaP细胞生长的能力。在水中储存在20°C和37°C的ApoDox无法将Dox递送至细胞核内，因此无法抑制LNCaP细胞的生长。总体而言，我们的研究表明，ApoDox在适当储存（4°C）的情况下在12周内具有非常好的稳定性，因此适合作为纳米载体用于向患者特异性递送抗癌药物。
