[Analysis and prospect of correlation between relative molecular weight and efficacy of polysaccharides from medicinal plant resources].

Polysaccharides from medicinal plant resources are a kind of polymers extracted from medicinal plants. They are complex long chains formed by different monosaccharides connected via glucosidic bonds. These polysaccharides usually have straight chain and branched chain structures, and their relative molecular weight changes greatly. Modern studies have shown that the biological activi-ty of polysaccharides from medicinal plant resources is closely related to their relative molecular weight. This paper first reviewed the preparation and detection methods of polysaccharides from medicinal plant resources with different relative molecular weights. Then, the paper summarized and analyzed the general experience of the correlation between efficacy and relative molecular weight of polysaccharides from medicinal plant resources with different molecular weights. It was considered that polysaccharides with large relative molecular weights(>100 kDa) play a leading role in immune regulation. Polysaccharides with medium relative molecular weights(10-100 kDa) play a leading role in immune regulation and the protection of the liver. Polysaccharides with small relative molecular weights(<10 kDa) play a leading role in anti-oxidation, regulation of intestinal flora, regulation of blood glucose and lipids, anti-fatigue, and the protection of nerves. Therefore, precise development of polysaccharides from medicinal plant resources based on relative molecular weight is expected to improve their biological activity and application value.

Specific molecular weight of Lycium barbarum polysaccharide for robust breast cancer regression by repolarizing tumor-associated macrophages.

The pro-tumorigenic M2-type tumor-associated macrophages (TAMs) in the immunosuppressive tumor microenvironment (TME) promote the progression, angiogenesis, and metastasis of breast cancer. The repolarization of TAMs from an M2-type toward an M1-type holds great potential for the inhibition of breast cancer. Here, we report that Lycium barbarum polysaccharides (LBPs) can significantly reconstruct the TME by modulating the function of TAMs. Specifically, we separated four distinct molecular weight segments of LBPs and compared their repolarization effects on TAMs in TME. The results showed that LBP segments within 50-100 kDa molecular weight range exhibited the prime effect on the macrophage repolarization, augmented phagocytosis effect of the repolarized macrophages on breast cancer cells, and regression of breast tumor in a tumor-bearing mouse model. In addition, RNA-sequencing confirms that this segment of LBP displays an enhanced anti-breast cancer effect through innate immune responses. This study highlights the therapeutic potential of LBP segments within the 50-100 kDa molecular weight range for macrophage repolarization, paving ways to offer new strategies for the treatment of breast cancer.

Gene engineered exosome reverses T cell exhaustion in cancer immunotherapy.

Cancer patients by immune checkpoint therapy have achieved long-term remission, with no recurrence of clinical symptoms of cancer for many years. Nevertheless, more than half of cancer patients are not responsive to this therapy due to immune exhaustion. Here, we report a novel gene engineered exosome which is rationally designed by engineering PD1 gene and simultaneously enveloping an immune adjuvant imiquimod (PD1-Imi Exo) for boosting response of cancer immune checkpoint blockage therapy. The results showed that PD1-Imi Exo had a vesicular round shape (approximately 139 nm), revealed a significant targeting and a strong binding effect with both cancer cell and dendritic cell, and demonstrated a remarkable therapeutic efficacy in the melanoma-bearing mice and in the breast cancer-bearing mice. The mechanism was associated with two facts that PD1-Imi Exo blocked the binding of CD8+ T cell with cancer cell, displaying a PD1/PDL1 immune checkpoint blockage effect, and that imiquimod released from PD1-Imi Exo promoted the maturation of immature dendritic cell, exhibiting a reversing effect on the immune exhaustion through activating and restoring function of CD8+ T cell. In conclusion, the gene engineered exosome could be used for reversing T cell exhaustion in cancer immunotherapy. This study also offers a promising new strategy for enhancing PD1/PDL1 therapeutic efficacy, preventing tumor recurrence or metastasis after surgery by rebuilding the patients' immunity, thus consolidating the overall prognosis.

Overcoming biological barriers by virus-like drug particles for drug delivery.

Virus-like particles (VLPs) have natural structural antigens similar to those found in viruses, making them valuable in vaccine immunization. Furthermore, VLPs have demonstrated significant potential in drug delivery, and emerged as promising vectors for transporting chemical drug, genetic drug, peptide/protein, and even nanoparticle drug. With virus-like permeability and strong retention, they can effectively target specific organs, tissues or cells, facilitating efficient intracellular drug release. Further modifications allow VLPs to transfer across various physiological barriers, thus acting the purpose of efficient drug delivery and accurate therapy. This article provides an overview of VLPs, covering their structural classifications, deliverable drugs, potential physiological barriers in drug delivery, strategies for overcoming these barriers, and future prospects.

Bioorthogonal Engineered Virus-Like Nanoparticles for Efficient Gene Therapy.

Gene therapy offers potentially transformative strategies for major human diseases. However, one of the key challenges in gene therapy is developing an effective strategy that could deliver genes into the specific tissue. Here, we report a novel virus-like nanoparticle, the bioorthgonal engineered virus-like recombinant biosome (reBiosome), for efficient gene therapies of cancer and inflammatory diseases. The mutant virus-like biosome (mBiosome) is first prepared by site-specific codon mutation for displaying 4-azido-L-phenylalanine on vesicular stomatitis virus glycoprotein of eBiosome at a rational site, and the reBiosome is then prepared by clicking weak acid-responsive hydrophilic polymer onto the mBiosome via bioorthogonal chemistry. The results show that the reBiosome exhibits reduced virus-like immunogenicity, prolonged blood circulation time and enhanced gene delivery efficiency to weakly acidic foci (like tumor and arthritic tissue). Furthermore, reBiosome demonstrates robust therapeutic efficacy in breast cancer and arthritis by delivering gene editing and silencing systems, respectively. In conclusion, this study develops a universal, safe and efficient platform for gene therapies for cancer and inflammatory diseases.

Integrated gut microbiota and fecal metabolome analyses of the effect of Lycium barbarum polysaccharide on D-galactose-induced premature ovarian insufficiency.

Premature ovarian insufficiency (POI) has become one of the greatest health threats to the reproduction of women during their fertile age. Lycium barbarum polysaccharides (LBPs) are known for anti-aging and reproductive protective functions. Here, we investigated the protective effect of LBP on POI mice and revealed its possible mechanism by a combination of 16S rRNA sequencing and metabolomics analysis. In the current study, female C57BL/6J mice treated with D-galactose were used as a model to investigate the reversal effect of LBP on the degenerative ovarian function. The ameliorative effect of LBP on POI was evaluated from the estrous cycle, ovarian reserve, serum sex hormone levels, and fertility testing. Additionally, 16S rRNA gene sequencing and untargeted metabolomics were integrated to analyze the effects of LBP on the gut microbiota and fecal metabolic profile in the POI mice. The results showed that LBP administration significantly increased the total number of follicles and the number of follicles at different developmental stages in the POI mice. In addition, LBP was effective in reducing the serum levels of follicle-stimulating hormone (FSH) and luteinizing hormone (LH), regularizing the disordered estrous cycle, and increasing the number of offspring of the POI mice. The results from 16S rRNA sequencing showed that LBP had beneficial effects on the composition and structure of the gut microbiota in the POI mice. In a metabolomics study, a total of 23 metabolites were finally identified as potential biomarkers of POI, and multiple pathways were regulated after the treatment of LBP, especially the arginine biosynthesis, glycerophospholipid metabolism and steroid hormone biosynthesis pathways. Pearson's correlation analysis showed that the regulation effect of LBP on metabolites was closely related to Faecalibaculum, Bilophila and Anaerofustis in the gut microbiota. In summary, the results demonstrated that LBP could improve the ovarian reserve and provides evidence both on the gut microbiota and metabolism, which provide beneficial support for the applications of LBP in female ovarian function degeneration.

A novel oncogenic enhancer of estrogen receptor-positive breast cancer.

Estrogen receptor-positive (ER+) breast cancer accounts for the majority of breast cancers diagnosed, and nearly 20% of patients do not respond to endocrine therapy. The pathogenesis of ER+ breast cancer has not been well elucidated. The enhancer is a cis-regulatory element that promotes gene transcription and plays an important role in the spatiotemporal expression of cellular genes. Nevertheless, the oncogenic enhancer and its role in the occurrence and progression of cancer remain unclear. Here, we report a novel oncogenic enhancer (named αE myc ) for c-Myc and reveal its activation mechanism in ER+ breast cancer. The results demonstrated that αE myc enhanced the transcription of downstream genes more than 20-fold. The deletion of the 7-bp region (GGTTGCA) in αE myc significantly downregulated the expression of c-Myc, resulting in cell nuclear changes, cell-cycle arrest, cell apoptosis, and finally, remarkable inhibition of cell proliferation. In conclusion, the present study discovers a novel oncogenic enhancer αE myc (801 base pairs [bp], at Chr8: 127668529-127669329) and offers a remarkable core enhancer target (GGTTGCA) of αE myc for gene therapy of ER+ breast cancer.

Targeted core-shell nanoparticles for precise CTCF gene insert in treatment of metastatic breast cancer.

Clustered regularly interspaced short palindromic repeats (CRISPR) technology emerges a remarkable potential for cure of refractory cancer like metastatic breast cancer. However, how to efficiently deliver the CRISPR system with non-viral carrier remains a major issue to be solved. Here, we report a kind of targeted core-shell nanoparticles (NPs) carrying dual plasmids (pHR-pCas9) for precise CCCTC-binding factor (CTCF) gene insert to circumvent metastatic breast cancer. The targeted core-shell NPs carrying pHR-pCas9 can accomplish γGTP-mediated cellular uptake and endosomal escape, facilitate the precise insert and stable expression of CTCF gene, inhibit the migration, metastasis, and colonization of metastatic breast cancer cells. Besides, the finding further reveals that the inhibitory mechanism of metastasis could be associated with up-regulating CTCF protein, followed by down-regulating stomatin (STOM) protein. The study offers a universal nanostrategy enabling the robust non-viral delivery of gene-editing system for treatment of severe illness.

Nanostructure of Functional Larotaxel Liposomes Decorated with Guanine-Rich Quadruplex Nucleotide-Lipid Derivative for Treatment of Resistant Breast Cancer.

Breast cancer is the most common malignant disease in women all over the world and its chemotherapy outcome is restricted by multidrug resistance. Here, a nanostructure by functional larotaxel liposomes decorated with guanine-rich quadruplex nucleotide-lipid derivative for treatment of resistant breast cancer is developed. The studies are performed on the resistant breast cancer cells and the cancer-bearing mice. The nucleotide-lipid derivative (DSPE-PEG2000 -C6 -GT28nt) is synthesized by introducing a hydrophobic hexyl linkage between GT-28nt (containing 17 guanines and 11 thymidines) and DSPE-PEG2000 -NHS, and is incorporated on the functional larotaxel liposomes for specific binding with nucleolin receptor on the resistant cancer cells. The studies demonstrate that the liposomes had long circulatory effect, targeted capability, and significant anticancer efficacy in resistant cancer-bearing mice. The studies further reveal their action mechanism, consisting of blocking depolymerization of microtubules, arresting cell cycle, blocking JAK-STAT signaling pathway, and inhibiting activity of antiapoptotic proteins. In conclusion, the functional larotaxel liposomes can be used for effective treatment of drug-resistant breast cancer, and this study also offers a novel targeted nanomedicine based on nucleotide-lipid derivative.

Regulating Stem Cell-Related Genes Induces the Plastic Differentiation of Cancer Stem Cells to Treat Breast Cancer.

Relapse of cancer is associated with multidirectional differentiation and unrestricted proliferative replication potential of cancer stem cells. Herein, we propose the plastic differentiation strategy for irreversible differentiation of cancer stem cells; further, salinomycin and its newly constructed functional liposomes are used to implement this strategy. Whole gene, cancer stem cell-related RNA, and protein expression analyses reveal that salinomycin induces the cancer stem cells into normal cells, dormant cells, and mature cancer cells. Besides, the results indicate that the gatekeeper is related to the inhibition of the protein kinase C (PKC) α signaling pathway. The differentiated normal or dormant cells are incorporated into normal tissue, whereas the rest are killed by chemotherapy. The findings would offer the evidence for plastic differentiation of cancer stem cells and propose a novel strategy for cancer therapy.

Engineered targeting tLyp-1 exosomes as gene therapy vectors for efficient delivery of siRNA into lung cancer cells.

Natural exosomes can express specific proteins and carbohydrate molecules on the surface and hence have demonstrated the great potentials for gene therapy of cancer. However, the use of natural exosomes is restricted by their low transfection efficiency. Here, we report a novel targeting tLyp-1 exosome by gene recombinant engineering for delivery of siRNA to cancer and cancer stem cells. To reach such a purpose, the engineered tLyp-1-lamp2b plasmids were constructed and amplified in Escherichia coli. The tLyp-1-lamp2b plasmids were further used to transfect HEK293T tool cells and the targeting tLyp-1 exosomes were isolated from secretion of the transfected HEK293T cells. Afterwards, the artificially synthesized siRNA was encapsulated into targeting tLyp-1 exosomes by electroporation technology. Finally, the targeting siRNA tLyp-1 exosomes were used to transfect cancer or cancer stem cells. Results showed that the engineered targeting tLyp-1 exosomes had a nanosized structure (approximately 100 nm) and high transfection efficiency into lung cancer and cancer stem cells. The function verifications demonstrated that the targeting siRNA tLyp-1 exosomes were able to knock-down the target gene of cancer cells and to reduce the stemness of cancer stem cells. In conclusion, the targeting tLyp-1 exosomes are successfully engineered, and can be used for gene therapy with a high transfection efficiency. Therefore, the engineered targeting tLyp-1 exosomes offer a promising gene delivery platform for future cancer therapy.

Nanosized functional miRNA liposomes and application in the treatment of TNBC by silencing Slug gene.

Background: Neo-adjuvant chemotherapy is an effective strategy for improving treatment of breast cancers. However, the efficacy of this treatment strategy is limited for treatment of triple negative breast cancer (TNBC). Gene therapy may be a more effective strategy for improving the prognosis of TNBC. Methods: A novel 25 nucleotide sense strand of miRNA was designed to treat TNBC by silencing the Slug gene, and encapsulated into DSPE-PEG2000-tLyp-1 peptide-modified functional liposomes. The efficacy of miRNA liposomes was evaluated on invasive TNBC cells and TNBC cancer-bearing nude mice. Furthermore, functional vinorelbine liposomes were constructed to investigate the anticancer effects of combined treatment. Results: The functional miRNA liposomes had a round shape and were nanosized (120 nm). Functional miRNA liposomes were effectively captured by TNBC cells in vitro and were target to mitochondria. Treatment with functional liposomes silenced the expression of Slug and Slug protein, inhibited the TGF-ß1/Smad pathway, and inhibited invasiveness and growth of TNBC cells. In TNBC cancer-bearing mice, functional miRNA liposomes exerted a stronger anticancer effect than functional vinorelbine liposomes, and combination therapy with these two formulations resulted in nearly complete inhibition of tumor growth. Preliminary safety evaluations indicated that the functional miRNA liposomes did not affect body weight or cause damage to any major organs. Furthermore, the functional liposomes significantly increased the half-life of the drug in the blood of cancer-bearing nude mice, and increased drug accumulation in breast cancer tissues. Conclusion: In this study, we constructed novel functional miRNA liposomes. These liposomes silenced Slug expression and inhibited the TGF-ß1/Smad pathway in TNBC cells, and enhanced anticancer efficacy in mice using combined chemotherapy. Hence, the present study demonstrated a promising strategy for gene therapy of invasive breast cancer.