| Nanoparticle drug delivery system has played an important role in the treatment of hepatocellular carcinoma in recent years.However,the main challenges faced by conventional nanoparticle include poor biocompatibility,low specific targeting and slow drug release in target sites.In this work,the stimuli(external/internal)responsive nanocarriers for targeting hepatocellular carcinoma was fabricated,which can specifically target hepatocellular carcinoma cells and control drug release in response to various stimulation,thereby achieving effective treatment of hepatocellular carcinoma.(1)Frist,a hepatocellular carcinoma-targeted exogenous stimuli-responsive nanocarrier was prepared.Galactose was used as the targeted ligand to actively target hepatocellular carcinoma through the endocytosis mediated by ASGPR,and drugs were released in response to stimulation of ultrasound to achieve effective treatment of hepatocellular carcinoma.Self-assembly of previously synthesized polymers(poly(lactobionamidoethyl methacrylate)-block-(hydroxy tetramethyl piperidinooxy)stearate,pLAMA-oa-SC)formed nanoparticles,which used as a drug carrier.The poly(lactobionamidoethyl methacrylate)(pLAMA)segments consisting of galactosylated residues can target hepatocellular carcinoma,and the linkage(-oa-)has ultrasonic stimuli responsiveness,which can break under ultrasonic conditions,thereby controlling drug release.Nanoscaled formation,approximate 53.0 nm in diameter for pLAMA-oa-SC self-assembly,was determined by dynamic light scattering(DLS)and transmission electron microscopy(TEM)measurement.The doxorubicin encapsulation efficiency and doxorubicin loading efficiency were determined to be approximate 60%and 5.66%,respectively.Using the Liquid Chromatograph Mass Spectrometry(LC-MS)measurement,the results showed that,prior to ultrasonication,no alkyl SC residue was affirmed for the synthesized pLAMA-oa-SC,as opposed to the distinct emergence of the alkyl SC residues post ultrasonication the ultrasonic unstable bond(-oa-)in pLAMA-oa-SC was broken after ultrasound treatment to generate SC residues,indicating that it had good ultrasonic response performance.The results of in vitro drug release showed that,approximate 70%of doxorubicin was estimated to release from pLAMA-oa-SC/doxorubicin at 24 h post ultrasound impetus,as opposed to reluctant release from pLAMA-oa-SC/doxorubicin in absence of ultrasonication(merely 40%of doxorubicin released at 24 h).The results of in vitro cell experiments showed that pLAMA-oa-SC/doxorubicin was more easily ingested by hepatocellular carcinoma cells,showing a specific targeting of hepatocellular carcinoma.After endocytosis into the cell,the drug was rapidly released under the stimulation of external ultrasound,which significantly inhibited the growth of liver cancer cells compared with the non-ultrasonic drug-loaded nanoparticles.(2)Based on the self-recognition and adhesion of hepatoma cells membrane,an endogenous stimuli-responsive nanoparticle was synthesized to actively target hepatocellular carcinoma.Then the anticancer drugs were rapidly released in the tumor cells due to the high intracellular concentration of GSH,hence improving the therapeutic effect of hepatocellular carcinoma.Firstly,we synthesized amphiphilic polymer(P-ss-G)with positive charge and disulfide bond and insensitive P-G which were structurally analogous to P-ss-G.The result of~1H NMR and FTIR proves that the polymer has been successfully synthesized.Redox-sensitive liposome nanoparticles(P-ss-G/D)were prepared by mixing positive carbamyl cholesterol(DC-Chol)with the redox-sensitive P-ss-G polymer.The blank(P-ss-G/D@M)nanoparticles coated with cell membrane were prepared by thin-film hydration method combined with electrostatic adsorption and membrane extrusion.DLS and TEM demonstrated that the diameter of the P–ss-G/D@M nanoparticles was approximate 140 nm with spherical shape.Moreover,the particle size changed significantly under the action of 10mM GSH,indicating that the nanoparticles had obvious GSH responsiveness.The sorafenib(Sf)(hepatocellular carcinoma treatment drug)was successfully loaded into the hydrophobic site to obtain drug-loaded nanoparticles(P-ss-G/D/Sf@M).The encapsulation efficiency and drug loading efficiency were 79.9%and 7.2%,respectively.In vitro release results showed P-ss-G/D/Sf@M could accelerate the drug release under the reduction condition,and the drug release reached more than 65%at 48 h,which was 25%higher than that under the non-reduction condition.It is indicated that P-ss-G/D/Sf@M can respond to the GSH quickly,thus achieving controlled release of the encapsulated drug.The results of in vitro cell experiments showed that nanoparticles coated with hepatoma cell membrane(Hep-G2)were more easily taken into hepatoma cells,showing the targeting of hepatocellular carcinoma.At the same time,the disulfide bond in the nanoparticles was broken under the high concentration of GSH,thereby the nanoparticles release drug rapidly,which could significantly inhibit the growth of liver cancer cells and improve the apoptosis rate. |
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