Natural polysaccharides with good biocompatibility and unique tumor immunomodulatory activity are becoming an important adjuvant anticancer therapy in clinic. In the field of pharmaceutics, natural polysaccharides can be used as not only bioactive components but also drug delivery carriers, as well as tumor-targeted ligands. Besides, various novel drug delivery systems based on natural polysaccharides exhibit unique advantages in regulating tumor immune microenvironment. In this review, we summarize the progress on natural polysaccharides in tumor microenvironment (TME) regulation and the designs of nano-sized drug delivery system, and point out challenges of polysaccharide-based drug delivery systems in the future application, and also give the potential solutions for these issues.

In this study, exosomes were extracted from human malignant melanoma cell A375. Folic acid (FA) receptor was used as target and triptolide (TPL) was used as model drug to prepare exosome targeted drug delivery system, FA-Exo/TPL. The physicochemical properties and antitumor effect were evaluated in vivo and in vitro. Gradient centrifugation method was applied to collect exosomes. Then, exosome was modified with FA for loading TPL. The particle sizes of the FA-Exo/TPL were about 100 nm with a double-layer membrane structure like a tray. It is characteristic of high encapsulation efficiency and drug loading. In vitro experiments showed that FA-Exo/TPL could be effectively uptaken by A375 cells, thus significantly inhibiting proliferation and promoting apoptosis the cells. In vivo experiment results showed that FA-Exo/TPL could effectively inhibit the growth of tumor tissue, prolong the model mice life cycle, and significantly reduce the systemic toxicity of the free drug, playing a synergistic and toxic role. Animal welfare and experimental procedures follow the regulations of the Animal Ethics Committee of Fudan University Shanghai Cancer Center. This study provides a new strategies and methods for the preparation of TPL against malignant melanoma.

Borneol (Bo) and Arg-Gly-Asp (RGD) co-modified docetaxel (DTX) loaded MPEG-PLGA nanoparticles (DTX-Bo-RGD-NPs) were prepared to improve the therapeutic effect of DTX against glioma after intranasal administration. DTX-Bo-RGD-NPs were prepared by emulsification-solvent evaporation method, and their morphology, particle size, zeta potential, drug loading capacity (DLC), stability, and in vitro release properties were investigated. The fluorescence probe coumarin-6 loaded NPs were prepared for investigating the NPs' uptake property on C6 and 16HBE cell models to evaluate in vitro targeting ability. The DiR loaded NPs were prepared for observing the fluorescence intensity at the brain tumor site after intranasal administration through in vivo imaging system in a C6 rat orthotropic model, evaluating the targeting ability in vivo. The anti-tumor effects of DTX-Bo-RGD-NPs were also investigated in such C6 rat orthotropic model in vivo. Animal welfare and experimental procedures are in compliance with the regulations of the Animal Ethics Committee of Shanghai University of Traditional Chinese Medicine. The results showed that DTX-Bo-RGD-NPs were spherical and uniformly distributed, with a particle size of about 140 nm and a zeta potential of -20 to -30 mV. The drug delivery system showed good stability and sustained release property in vitro, and favorable brain tumor targeting effect in vitro and in vivo. Such novel drug delivery system significantly improved the accumulation of DTX-Bo-RGD-NPs in tumor sites and displayed a higher brain tumor targeting efficiency, providing promising therapeutics of DTX for the treatment of glioma after intranasal administration.

This study aims at the critical role of P-glycoprotein (P-gp) in tumor drug resistance, taking advantage of the adenosine triphosphate (ATP) dependence of P-gp mediated drug transport and efflux across the cell membrane. Mitochondrial targeted calcium arsenite/doxorubicin (DOX) lipid nanoparticles were constructed via hydrothermal method and thin-film dispersion method for reversing tumor drug resistance. The results showed that the lipid nanoparticles were uniform in size and well dispersed with a mean particle size of (261 ± 7) nm, zeta potential of (-9.6 ± 1.3) mV. The DOX loading efficiency and encapsulation efficiency were 22.6% and 84.0%. The in vitro drug release profile was pH-dependent; the drug accumulation at mitochondria was significantly increased, which then caused overload of calcium and inhibition of P-gp and ATP, thereby reversing tumor drug resistance. The simultaneously released arsenite ion and DOX could synergistically kill the tumor cells. In summary, the lipid nanoparticles prepared in this study have uniform particle size, high drug loading efficiency and encapsulation efficiency, excellent colloidal stability, pH responsiveness, and impressive ability to reverse tumor drug resistance, which may hold great potential in further clinical applications.

Drug combination can effectively enhance the anti-tumor effect, reduce the drug dose, and improve medication safety. The use of nano-carrier for drug co-delivery can effectively avoid the differences in drug delivery behavior in vivo. Triptolide and celastrol are the main anti-tumor active components of Tripterygium wilfordii Hook f. Modern studies have shown that the combination of triptolide and celastrol can significantly enhance the antitumor effect, but they are limited by poor water solubility and low tumor tissue delivery rate. In this study, a biomimetic erythrocyte membrane liposome co-loaded with triptolide and celastrol was prepared to characterize the morphology, particle size, potential, drug release, serum stability, and other properties. The immunogenicity, uptake behavior, and anti-cell proliferation ability of the biomimetic liposome was compared. All the animal experiments were carried out in accordance with protocol evaluated and approved by the Ethics Committee of Chengdu University of Traditional Chinese Medicine (Chengdu, China). The results showed that the biomimetic erythrocyte membrane liposome co-loaded with triptolide and celastrol (C+T/RBCm@Lip) in this study had an average particle size of 119.12 ± 2.78 nm and a spherical "core-shell" structure. The zeta potential value was -16.9 ± 1.2 mV, and the drug release behavior in vitro was slow. In addition, the process of coating the cell membrane maintained the characteristics of erythrocyte membrane protein, had good stability in serum, and could effectively avoid the recognition and clearance of macrophages, without causing immunogenicity in vivo. The uptake effect of co-loaded biomimetic liposomes on HepG2 hepatocellular carcinoma cells was enhanced compared with that of uncoated cell membrane liposomes, and the inhibitory effect on proliferation of HepG2 cells was enhanced. In conclusion, the biomimetic liposomes coated with erythrocyte membrane prepared in this study is beneficial to the anti-tumor delivery of triptolide and celastrol, and could enhance the inhibitory effect on the growth of HepG2 liver cancer cells, providing a new idea for the anti-tumor application of Tripterygium wilfordii Hook f.

This research aimed at the key issue that chemical drugs and Chinese medicine hydrophilic small molecule anti-tumor drugs were difficult to break through the dense interstitial permeability barrier of pancreatic cancer to achieve the key problem of drug efficacy in the deep part of tumor tissue. To solve this problem, the lipophilic molecule squalene (SQ) and the hydrophilic anti-tumor drug chidamide (CHI) were linked by a trypsin responsive bond to form a prodrug (SQ-CHI) and a folic acid modified prodrug self-assembled nanoparticles (FA-SQ-CHI NPs) were further developed. The feature of prodrug molecules and nanoparticles were characterized. The in vitro release characteristics and cytotoxicity of blank vector were investigated. The efficacy and permeability of the prodrug nanoparticles in the PSN-1 monolayer cell and PSN-1/HSPC co-cultured tumor spheroids model was evaluated. The results showed that SQ-CHI prodrug molecules and FA-SQ-CHI NPs were successfully developed. The nanoparticles were regular spherical, well-dispersed, with a particle size of (173.3 ± 1.5) nm, a drug load of (59.02 ± 0.8) % and showed trypsin responsive release ability. The prodrug nanoparticles can significantly enhance the penetration and anti-proliferation effects of CHI in the PSN-1/HSPC tumor spheroids. In conclusion, the construction of folic acid-modified SQ-CHI prodrug self-assembled nanoparticles can significantly enhance the penetration of CHI in the pancreatic cancer microenvironment in vitro. This research would provide a new idea for the construction of targeted drug delivery system for chemical drugs and Chinese medicine hydrophilic small molecule drugs in the application of anti-pancreatic cancer.

Cryptotanshinone (CPT), an active ingredient with the inhibitory effect on brain glioma cells, is trapped with poor solubility and low tumor permeability. Therefore, it is urgent to design nano drug delivery systems characterized with deep penetration and accurate targeting. In the present study, tLyp-1 modified liposomes loaded with CPT (tLipo/CPT) was prepared by emulsion solvent evaporation method. Peptide tLyp-1 which targeting tumor angiogenesis and neuropilin receptors (NRP) was modified on surface of CPT liposomes, with the aim of active targeting brain glioma cells and further release CPT precisely. The size and polymer dispersity index (PDI) of tLipo/CPT were (162.2 ± 14.6) nm and 0.24 ± 0.03. The optimal molar ratio of tLyp-1 modified on CPT liposomes was 0.5% determined by intracellular fluorescence parameters. The morphology displayed a smooth sphericity structure as determined by transmission electron microscope. Efficiency of CPT encapsulated in tLipo/CPT was detected by high performance liquid chromatography. The encapsulation efficiency of CPT was (70.06 ± 7.22) %. Liposomes modified with tLyp-1 peptide (tLipo) were internalized more than liposomes not modified with tLyp-1 (Lipo) by GL261 cells. Fluorescence intensity of tLipo in GL261 cells increased 40% than that of Lipo. Furthermore, we proved that the intake of tLipo/CPT in GL261 cells was mediated by NRP-1 receptor. MTT analysis indicated that tLipo/CPT significantly inhibit the proliferation of GL261 cells. The half maximal inhibitory concentration (IC₅₀) was 5.70 μmol·L^-1. In vitro blood-brain barrier (BBB) model experiment indicated that tLipo/CPT could penetration across BBB. Moreover, in vivo fluorescence biodistribution study indicated tail vein injection of DiR labeled tLipo after 0.5 h, DiR fluorescence could be observed in the brain of mice. Even after 24 h, DiR fluorescence still was observed in the brain. Our research certified that tLipo/CPT can penetrate the BBB and show effect of anti-glioma by inhibiting the proliferation of GL261 cells. The animal experiment was carried out in accordance with protocol evaluated and approved by the Ethics Committee of Nanjing University of Chinese Medicine.

To explore the effect of tanshinone IIA (TanIIA) on the occurrence and development of breast cancer, we employed the mouse mammary tumor virus-polyomavirus middle T antigen (MMTV-PyMT) transgenic mice as a spontaneous breast cancer mouse model. Animal welfare and experimental procedures were in accordance with the regulations of the Animal Ethics Committee of Nanjing University of Chinese Medicine. The animals were divided into control group, low-dose TanIIA treatment group (30 mg·kg^-1·day^-1), and high-dose TanIIA treatment group (60 mg·kg^-1·day^-1). The treatment was administered orally and daily for 5 weeks. The mice were sacrificed after final treatment. Mammary gland and lung were collected for histopathology studies. We evaluated the chemoprophylaxis effect of TanIIA on breast cancer in mice according to the pathological characteristics of breast cancer at different stages of development. Immunofluorescence staining were employed for blood vessel analysis. The expression levels of E-cadherin, proliferating nuclear antigen (PCNA), and oncogene c-Myc were detected by immunohistochemistry. Flow cytometry was used to analyze cell cycle and Cytoscape was used to construct drug-disease protein-protein interaction (PPI) network. Our results showed that TanIIA inhibits breast tumor progression by delaying malignancy from adenoma to early carcinoma, and inhibits blood vessel formation during tumor development. TanIIA (60 mg·kg^-1·day^-1) inhibits the expression levels of PCNA and c-Myc, upregulates the expression of E-cadherin. In addition, cell cycle experiments showed that the cell cycle of PyMT primary mammary cells in the high-dose TanIIA group was arrested in the G0/G1 phase. Our study demonstrated that TanIIA can significantly inhibit breast tumor progression in MMTV-PyMT mouse model, which may be related to the inhibition of angiogenic switch and cell cycle arrest.

Plant natural products (PNPs) are important sources of innovative drugs. They are mainly obtained by isolation or extraction from plants. Low content and with structural analogues in plants result in high production cost, which restricts the research and application of PNPs. While biopathway construction by synthetic biology provides an alternative for production of PNPs. By biosynthetic pathway analysis of PNPs and reconstructing the biopathway in microorganisms, we can produce PNPs in cell factories efficiently. Recently, several predominantly international reports about biosynthesis of PNPs and its synthetic biology production, triggered the researches of PNPs. Abundant traditional Chinese medicine resources and profound cultural heritage of Chinese medicine make biosynthesis pathway analysis of PNPs to be a research hotspot. And some of the studies have achieved significant progress. Here, recent progress in the biosynthesis of plant natural products and its synthetic biology was reviewed. In particular, the application of new methods and technologies in recent years were summarized and discussed. This will provide reference for the biopathway construction of plant natural products.

Single cell "omics" technology enables the capture of genome, transcriptome, proteome and other omics information in a high-throughput and unbiased manner at single-cell resolution, allowing the characterization of the functional state of individual cells to reveal their heterogeneity and differential responses to drug treatment. This technology has wide application in pharmacological research, facilitating drug screening, efficacy evaluation, and mechanistic studies. We envision that, in the field of traditional Chinese medicine (TCM), single cell omics technology can be applied in the identification of active ingredients and drug targets, and elucidation of drug mechanism of action. In this article, we briefly introduce the single cell omics technology - particularly single cell transcriptome sequencing, and review its application in the field of modern drug research. Based on that, we propose the concept of "single cell pharmacology" and articulate how it can be applied to transform the pharmacological research of TCM and promote TCM modernization.