Effect of targeted therapy with cisplatin-loaded magnetic nanoparticles combined with radiotherapy for nasopharyngeal carcinoma in nude mice / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the effect of target therapy with cisplatin (CDDP)-loaded magnetic nanoparticles (MNP) in combination with chemoradiotherapy against nasopharyngeal carcinoma cell growth in nude mice.</p><p><b>METHODS</b>Thirty-six BALB/c mice with implanted tumor of CNE-2 cells were randomly divided into 6 groups (n=6), including the control group, radiotherapy group, CDDP group, CDDP plus radiotherapy group, CDDP-MNP group, and CDDP-MNP plus radiotherapy group. The mice were given 0.3 ml normal saline (control) or corresponding agents (3 mg/kg) via the tail vein, and 0.5 ml saline was administered intragastrically before the injections. Before and after the treatment, the body weight, tumor volume and weight, and the tumor inhibition rates were measured. The proliferating cell nuclear antigen (PCNA) index was calculated on the basis of immunohistochemical staining.</p><p><b>RESULTS</b>Except for the cisplatin group, all the treated groups showed significantly reduced tumor volume as compared with that in the control group (P<0.05) with lowered body weight. Compared with the cisplatin group, the combined treatment groups showed significantly higher tumor inhibition rate (P<0.05), but the effect showed no significant difference from that in the radiotherapy group (P>0.05).</p><p><b>CONCLUSION</b>Targeted therapy with CDDP-loaded MNP alone or in combination with radiotherapy can effectively inhibit the growth of nasopharyngeal carcinoma in nude mice without increasing the toxicity.</p>

Targeted distribution of cis-platin magnetic nanoparticles in mice / 南方医科大学学报

<p><b>OBJECTIVE</b>To evaluate the targeted distribution of cis-platin magnetic nanoparticles (CDDP-MNP) in normal mice.</p><p><b>METHODS</b>Thirty-two normal mice were randomly assigned into 4 equal groups. External magnetic field of 4100-4200 Gs was established in the unilateral kidney area of each mouse, and CDDP-MNP was administered via the tail vein, with the external magnetic field maintained in groups A, B, C, and D for 30 min and 1, 2 and 4 h after the injection, respectively. A flame atomic absorption spectrometer (AAS) was used to detect CDDP concentration in the mouse kidney tissues. Magnetic resonance imaging (MRI), Prussian blue staining, and transmission electron microscopy (TEM) were used to detect the distribution of the magnetic nanoparticles in vivo.</p><p><b>RESULTS</b>In groups A, B and C, the concentrations of CDDP in the targeted kidney tissues increased significantly in comparison with those in non-targeted kidney. The signal intensity of the targeted kidney tissue was lower than that of the non-targeted kidney on T2-weighted MR images. TEM and Prussian blue staining demonstrated MNP distribution in the lumens and endothelial cells of the blood capillary in the kidney tissue.</p><p><b>CONCLUSION</b>CDDP-MNP allows targeted distribution induced by external magnetic field in normal mice after intravenous injection.</p>