RESUMEN
<p><b>OBJECTIVE</b>To explore the effects of the magnetic c-erbB-2 antisense probe of different concentrations on the morphology and expression of SK-Br-3 cancer cells in vitro.</p><p><b>METHODS</b>Breast cancer SK-Br-3 cells were transfected for 24 h by antisense probe at an iron concentration of 5, 10, 25, 50, and 100 mg/L, respectively. The distribution and content of iron particles in SK-Br-3 cells was determined by Prussian blue staining, electron microscopy, and atomic absorption spectrometry. Cell viability was observed by trypan-blue exclusion and CCK-8 test. The protein expression of c-erbB-2 was assessed by the Western blot analysis. The changes of the signal strength were considered by magnetic resonance imaging (MRI).</p><p><b>RESULTS</b>c-erbB-2 antisense probe was uptake by SK-Br-3 cells in a concentration-dependence manner within a certain range (5, 10, and the Medicine Scientific Research Project of Chongqing Health Bureau (062025)25 mg/L). When the probe concentration was 25 mg/L, iron content in cells was (18.38±0.28) pg, the cell vitality, survival, and c-erbB-2 protein expression were reduced significantly (all P<0.05), and the T2 value was lower significantly (P<0.05). However, the results of 50 mg/L or 100 mg/L group showed no significant difference with the 25 mg/L group (P>0.05).</p><p><b>CONCLUSION</b>The magnetic c-erbB-2 antisense probe can effectively transfect and specifically inhibit the expression of SK-Br-3 cell lines at the iron concentration of 25 mg/L.</p>