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Hepatocellular carcinoma (HCC) is one of the most common cancers worldwide, with insidious onset, insensitive to chemotherapy and poor prognosis, which make its clinical treatment face an enormous challenge. In recent years, with the rapid development of nanotechnology, increasing kinds of nanomedicine come to the forefront in biomedical fields. Through rational design, nanomedicine can be prepared in suitable size and modified with specific liver targeting ligands. Moreover, various therapeutic agents of different mechanisms can be co-loaded into the same nanosystem, thus achieving the synergistic therapeutic effects towards HCC. Nanomedicine is able to enhance drug bioavailability and liver-targeting effect as well as reduce the side effects to normal tissues, which provide a great potential in HCC therapy. This review summarizes the recent progress in the application of nanomedicine for HCC therapy from two aspects: their liver-targeting design strategies and the recent progress in combination therapy of HCC.
ABSTRACT
Objective To prepare a redox-responsive doxorubicin-loaded nanoparticle,and to study its in vitro realease behavior and targeting effect on heptoma cells.Methods Cystamine was grafted on the side chains of hyaluronic acid with 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride/N-hydroxysuccinimide catalyst,and then β-cyclodextrin (β-CD) was conjugated on the amine groups of the cystamine by Schiff's base reaction to prepare β-CD modified hyaluronic acid (HACD).The HACD/DOX nanoparticles were prepared by encapsulating DOX into HACD using dialysis method.The drug loading,encapsulation efficiency,particle size and distribution,zeta potential and other physical and chemical properties,as well as in vitro drug release behavior of the HACD/DOX nanoparticles were characterized.The cytotoxicity of HACD/DOX nanoparticles to HepG2 cells was studied by cell counting kit-8 (CCK-8) method.The targeting effect of HACD/DOX nanoparticles on HepG2 cells was studied using flow cytometry and confocal laser scanning microscopy (CLSM).Results HACD were successfully synthesized,which could carry DOX to form uniform homogeneous nanoparticles.The drug loading of DOX in the nanoparticles was (16.1±0.2)％ and the encapsulation efficiency was (64.2±0.9)％.The transmission electron microscope images indicated that the shape of the HACD/DOX nanoparticles was homogeneous sphere.The results of granularity analysis showed that the average size of the HACD/DOX nanoparticles was (203.1 ±2.5) nm with a narrow size distribution (PDI =0.202).The zeta potential of the HACD/DOX nanoparticles was (-29.1±0.8) mV.The in vitro release behavior of the nanoparticles exhibited obvious redox-sensitivity.The results of in vitro cytotoxicity showed that the blank carrier material HACD had no obvious toxicity to hepatoma cells,and the HACD/DOX nanoparticles could effectively kill hepatoma cells with the 0.38 μg/ml half maximal inhibitory concentration (IC50) value at 48 h.Flow cytometry and CLSM results demonstrated that the HACD/DOX nanoparticles could target hepatoma cells through the mediating effect of hyaluronic acid.Conclusions The prepared HACD/DOX nanoparticles have suitable particle size,high drug loading and encapsulation efficiency,and can release DOX under the stimulation of reducing agent.These nanoparticles have obvious targeting effect on hepatoma cells,which is expected to be applied as the drug delivery system of hepatocellular carcinoma (HCC) therapy.
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Objective To explore the feasibility and value of dynamic contrast-enhanced (DCE-MRI) parameters in assessing early effects of anti-angiogenesis medicine in targeted therapy for tumors.Methods Twenty BALB/C-nu nude mice were injected subcutaneously with human colon cancer cells HT-29 to the right hind leg.The nude mice were evenly divided into the experimental group and control group with 10 mice in each group.The mice of experimental group were intraperitoneally injected with bevacizumab,and the control group were injected with the same volume of saline.DCE-MRI was performed before medication and one hour,24 h and 48 h after medication.The Ktrans,Kep,Ve and initial area under enhancement curve (iAUC) of DCE-MRI were analyzed.The animals were sacrificed 48 hours after medication.Microvessel density (MVD) of the tumors was detected by immunohistochemistry.One way analysis of variance was performed to analyze parameters of DCE-MRI.The Pearson correlation coefficient was used to analyze the correlation between parameters of DCE-MRI and MVD.Results Under DCE-MRI,the edge of subcutaneous colon cancer xenografts was obviously gradually enhanced,pseudo color indicated high perfusion,the strength degree of the central region was low and which meant low perfusion.The differences in Kep of different time point of experimental group were statistically significant (F=3.752,P=0.016) ; there as no significant difference in other parameters of DCE MRI (all P＞0.05).There was no significant difference in Ktrans and Kep before medication and one hour after medication (all P＞0.05).There were significant difference in Ktrans and Kep 24 hour and 48 hour after medication between experimental group (24 hour∶ (0.095 ± 0.039) min-1 and (0.297 ± 0.141) min-1,48 hour∶ (0.090±0.033) min 1 and (0.314±0.148) min-1) and control group (24 hour∶ (0.150±0.074) nin-1 and (0.494±0.126) min-1,48 hour∶ (0.171±0.045) min-1 and (0.441± 0.092) min-1) (F24h =4.824 and 11.386,F48h =22.605 and 5.455,all P＜0.05).There was no significant difference in Ve and iAUC between two groups at different time points (all P＜0.05).MVD of experimental group was lower than that of control group.Ktrans and Kep were positively correlated with MVD (r=0.745 and 0.400,both P＜0.05).Conclusion Ktrans and Kep parameters of DCE-MRI may be used in monitoring the earlier effects of anti-angiogenesis medicine in targeted therapy for colon cancer.
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ObjectiveThe aim was to construct the recombinant plasmid of pET-28a-G-protein pathway suppressor 2 (GPS2) GPS2,express GPS2 protein in E.coli,and obtain specific polyclonal antiserum of GPS2.MethodsGPS2 gene was obtained and the amplified fragment was then cloned into E.coli expression vector pET-28a to construct recombinant plasmid.The recombinant plasmid was transformed into E.coli expression strain BL21(DE3).IPTG induces the expression protein GPS2 protein,and the induction conditions were optimized.The induced product was purified by Ni2+ affinity chromatography,and the purified product was dialyzed with buffer for refolding.The purified protein can be used as antigen,injected to immunize male New Zealand white rabbit to get polyclonal antiserum.The titer and specificity of the rabbit antiserum were detected by ELISA and Western Blotting.ResultsThe E.coli expression vector pET-28a-GPS2 was constructed successfully and the recombinant protein was efficiently expressed and purified.The purified protein was used to immunize male New Zealand white rabbit to get polyclonal antiserum and the ELISA and Western Blot results showed that the high titer of specific polyclonal antiserum.ConclusionGSP2 could be highly expressed in E.coli.Antiserum of GPS2 protein can be obtained by the purified recombinant to analyze its function.