The Study On Effective Concentration And Time Of Magnetic C-ERBB2Antisense Probe Transfected Into SK-Br3Breast Cancer Cell Lines In Vitro

Background: Malignant tumors is the principal disease that cause todeath of mankind, which become the first or the second leading cause ofdeath among residents in many countries, this is because there is still lack ofspecificity diagnosis, early metastasis warning, clinical curative effectprediction and effective treatment methods for tumor. Molecular imagingcan reveal the biological characteristics of organization more deeply basedon the anatomical configuration, detect the prophase molecular variation andthe pathological change process, and provide quantitative, timing, visualmolecular and genetic information in noninvasive and repeatable way, andtherefore it is expected to achieve specificity diagnosis in the level of tumorgene. In molecular imaging study, the preparation of high specificity, goodaffinity probes, is the key factor to realize living imaging. with the referenceof antisense gene technology in molecular biology, the probe is used for SK-Br3tumor cell line of high expression c-erbB2oncogene with transfectionin vitro, and it has been preliminarily found the function of diagnosis and treatment, based on the success of the research team in the preparation of c-erbB2cancer gene ASODN(antisenseoligonucleotides) probe labeled withAPIO(superparamagnetic iron oxide, SPIO).Objective：To explore the effects of the magnetic c-erbB2antisenseprobe of different concentrations and different incubation time points on themorphology and expression of SK-Br-3cancer cells in vitro,and draw aneffective SK-Br3cell-transfection concentration and optimal time data ofantisense probe.Methods： On the one hand, breast cancer SK-Br3cells weretransfected for24h by antisense probe at an iron concentration of5,10,25,50and100mg/L, respectively, on the other hand breast cancer SK-Br3cellswere transfected by antisense probe with iron concentration25μg/mL for6h,12h,24h,36h and48h, respectively. The distribution and content of ironparticles in SK-Br-3cells was determined by Prussian blue staining, electronmicroscopy, and atomic absorption spectrometry. Cell viability wasobserved by trypan-blue exclusion and CCK-8test. The protein expressionof c-erbB2was assessed by the western bloting. The changes of the signalstrength were considered by magnetic resonance imaging (MRI).Results：C-erbB-2antisense probe was uptaken by SK-Br3cells in airon concentration and incubation time dependence manner within a certainrange (5mg/L,10mg/L, and25mg/L;6h,12h,24h). When the probeconcentration was25mg/L and incubation time24h, iron content in cells was (18.38±0.28) pg, the cell vitality, survival and c-erbB2proteinexpression was reduced significantly (P<0.05), and the T2value was lowersignificantly (P<0.05). However, the results of50mg/L or100mg/L groupshowed no significant difference with the25mg/L group (P>0.05); Theresults of36h and48h group compared with24h group were notsignificantly different (P>0.05).Conclusions：The magnetic c-erbB2antisense probe can effectivelytransfect and specifically inhibit the expression of SK-Br3cell lines at theiron concentration of25mg/L after transfected for24h.