The Construction Of ADM/oHA-ss-PTX Based Co-delivery Intelligent Micelles And Ant-breast Cancer Mcf-7 In Vitro

Neoadjuvant chemotherapy plays an important role in the treatment of breast cancer.However,its maximum benefit has been limited in the clinical treatment owing to the defect of traditional drug dosage forms.Therefore,a co-delivery reduction-sensitive micelle?ADM/oHA-ss-PTX?based on oligosaccharide Hyaluronic acid-based doxorubicin and paclitaxel to improve the treatment of Neoadjuvant chemotherapy benefit.The work content was divided into four parts,?1?oHA-ss-PTX was synthesized,?2?physicochemical of co-load intelligent micelles was detected,?3?biocompatibility of co-load intelligent micelles was evaluated,?4?antitumor effect of co-load intelligent micelles was assessed in vitro.oHA-ss-PTX was synthesized via three steps.Firstly,paclitaxel was carboxylated?2?sPTX?by esterification of succinic anhydride with paclitaxel.Secondly,cystamine was grafted to oHA via amide condensation to achieve aminate of oHA?oHA-ss-NH₂?.Lastly,amphiphilic conjugate was produced through re-amide condensation using carboxyl group in 2?sPTX with an amino group in oHA-ss-NH₂.And chemical structure of 2?sPTX,oHA-ss-NH₂ and oHA-ss-PTX was determined using ¹H-NMR and FT-IR.The single factor analysis method had found that the system has good drug loading performance and the drug loading of PTX and ADM was up to 22.8±1.6%and 7.6±0.2%respectively.And ADM/oHA-ss-PTX micelle was prepared by the direct dissolution method not only had a lower critical micelle concentration?CMC=124?g/mL?,but also particle size show Gaussian distribution?particle size=201±3 nm,PDI=23.0±3.8%?.In addition,the system exhibits superior stability in 4 C°environments with particle size change of<30 nm within 72 hours.In vitro drug release studies illustrated that ADM and PTX were released 80.5%and 49.9%from the system after 48 h in GSH?10 mM?medium,respectively.On the contrary,release of drugs was inhibited drastically only 46.0%and 22.2%in without GSH medium.And the release of PTX was slower than that of ADM,which lays the foundation for the implementation of Neoadjuvant chemotherapy strategies for synergistic therapy and maintenance therapy between drugs.Hemolysis experiments of ADM/oHA-ss-PTX micelles demonstrate that this system display low hemolysis even at high concentrations?p<0.05?.BSA adsorption experiments showed that the protein adsorption of this system was relative to time and concentration,but it possessed lower BSA adsorption rate?9.4%?than the free drug?16.8%,p<0.05?.Human umbilical vein endothelial cells?ECs?had been used as a model for evaluation of cytotoxicity and experiment result shows the drug delivery system inhibited ECs cells at a high concentration of less than 30%,showing relatively slight cytotoxicity and good biocompatibility.Breast cancer MCF-7 was being used as a model to assess the synergistic anti-breast cancer effect,target,cellular uptake and cells migration.The results of MTT experiments display that MCF-7 cells can be significantly curbed by ADM/oHA-ss-PTX micelles.It's half inhibitory concentration(IC₅₀)was 2.228?M,which was lower than free mixed drugs5.547?M?p<0.05?.And the synergy index CI₅₀ of ADM/oHA-ss-PTX micelle was 0.459 less than 1,which reflect the superior synergistic antitumor effect of system.Competitive antagonism experiments showed that the system was uptake by oHA-saturated MCF-7 cells was significantly lower than that of unsaturated MCF-7 cells?p<0.05?,which was related to the inhibition of the CD44-mediated endocytosis pathway.The results of uptake experiments also demonstrate that the uptake rate of ADM/oHA-ss-PTX by MCF-7 cells will increase significantly with time.The results of the scratch test illustrated that healing of scratches was more obviously prevented via the system than the unbound drugs.And exhibits more effective tumor migration inhibition.The above results demonstrate that ADM/oHA-ss-PTX micelles was successfully produced for co-delivery PTX and ADM.And it was possessed variety advantages including reduction sensitivity,good biocompatibility and excellent synergistic antitumor effects.Therefore,we believe that the system is promising drug delivery system and can be available for a theoretical basis for the development of drug delivery systems in the field of multi-drug combination or maintenance therapy.