d-lactate modulates M2 tumor-associated macrophages and remodels immunosuppressive tumor microenvironment for hepatocellular carcinoma.

The polarization of tumor-associated macrophages (TAMs) from M2 to M1 phenotype demonstrates great potential for remodeling the immunosuppressive tumor microenvironment (TME) of hepatocellular carcinoma (HCC). d-lactate (DL; a gut microbiome metabolite) acts as an endogenous immunomodulatory agent that enhances Kupffer cells for clearance of pathogens. In this study, the potential of DL for transformation of M2 TAMs to M1 was confirmed, and the mechanisms underlying such polarization were mainly due to the modulation of phosphatidylinositol 3-kinase/protein kinase B pathway. A poly(lactide-co-glycolide) nanoparticle (NP) was used to load DL, and the DL-loaded NP was modified with HCC membrane and M2 macrophage-binding peptide (M2pep), forming a nanoformulation (DL@NP-M-M2pep). DL@NP-M-M2pep transformed M2 TAMs to M1 and remodeled the immunosuppressive TME in HCC mice, promoting the efficacy of anti-CD47 antibody for long-term animal survival. These findings reveal a potential TAM modulatory function of DL and provide a combinatorial strategy for HCC immunotherapy.

Nanodelivery of scutellarin induces immunogenic cell death for treating hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) causes the immunosuppressive tumor microenvironment (TME) resistant to current immunotherapy. The immunogenic apoptosis (currently termed immunogenic cell death, ICD) of cancer cells may induce the adaptive immunity against tumors, thereby providing great potential for treating HCC. In this study, we have confirmed the potential of scutellarin (SCU, a flavonoid found in Erigeron breviscapus) for triggering ICD in HCC cells. To facilitate in vivo application of SCU for HCC immunotherapy, an aminoethyl anisamide-targeted polyethylene glycol-modified poly(lactide-co-glycolide) (PLGA-PEG-AEAA) was produced to facilitate SCU delivery in this study. The resultant nanoformulation (PLGA-PEG-AEAA.SCU) remarkably promoted blood circulation and tumor delivery in the orthotopic HCC mouse model. Consequently, PLGA-PEG-AEAA.SCU reversed the immune suppressive TME and achieved the immunotherapeutic efficacy, resulting in significantly longer survival of mice, without inducing toxicity. These findings uncover the ICD potential of SCU and provide a promising strategy for HCC immunotherapy.

Delivery of melarsoprol using folate-targeted PEGylated cyclodextrin-based nanoparticles for hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) is the most common type of primary liver cancer, and has become one of the most lethal malignancies in the world. Although chemotherapy remains a cornerstone of cancer therapy, the number of chemotherapeutic drugs approved for HCC is low, and emerging therapeutics are needed. Melarsoprol (MEL) is an arsenic-containing drug, and has been applied in the treatment of human African trypanosomiasis at the late stage. In this study, the potential of MEL for HCC therapy was investigated for the first time using in vitro and in vivo experimental approaches. A folate-targeted polyethylene glycol-modified amphiphilic cyclodextrin nanoparticle was developed for safe, efficient and specific delivery of MEL. Consequently, the targeted nanoformulation achieved cell-specific uptake, cytotoxicity, apoptosis and migration inhibition in HCC cells. Furthermore, the targeted nanoformulation significantly prolonged the survival of mice with orthotopic tumor, without causing toxic signs. This study indicates the potential of the targeted nanoformulation as an emerging chemotherapy option for treating HCC.

Nano Delivery of Chemotherapeutic ICD Inducers for Tumor Immunotherapy.

Immunogenic cell death (ICD, also known as immunogenic apoptosis) of malignant cells is confirmed to activate the host immune system to prevent, control, and eliminate tumors. Recently, a range of chemotherapeutic drugs have been repurposed as ICD inducers and applied for tumor immunotherapy. However, several hurdles to the widespread application of chemotherapeutic ICD inducers remain, namely poor water solubility, short blood circulation, non-specific tissue distribution, and severe toxicity. Recent advances in nanotechnology and pharmaceutical formulation foster the development of nano drug delivery systems to tackle the aforementioned hurdles and expedite safe, effective, and specific delivery. This review will describe delivery barriers to chemical ICD inducers and highlight recent nanoformulations for these drugs in tumor immunotherapy.

Nano co-delivery of Plumbagin and Dihydrotanshinone I reverses immunosuppressive TME of liver cancer.

Hepatocellular carcinoma (HCC) is resistant to current immunotherapy. This poor outcome mainly results from the immunosuppressive characteristics of tumor microenvironment (TME). Accumulating evidence indicates that some chemotherapy agents trigger immunogenic cell death (ICD), providing a promising strategy to remodel the immunosuppressive TME. The role of Plumbagin (PLB, a naphthoquinone compound from Plumbago zeylanica L.) as the ICD inducer for HCC cells was confirmed in this study. Dihydrotanshinone I (DIH, a phenanthraquinone compound of Salvia miltiorrhiza) functioned as the ICD enhancer by generating the reactive oxygen species (ROS). A poly(D,L-lactic-co-glycolic acid) (PLGA)-based nanoparticle (NP) was used to co-encapsulate PLB, DIH and NH4HCO3 (a pH sensitive adjuvant). This NP was further coated with the mannose-inserted erythrocyte membrane to produce a nanoformulation. This nanoformulation significantly increased the half-life and tumor targeting of two drugs in orthotopic HCC mice, generating chemo-immunotherapeutic effects for reversal of immunosuppressive TME. Consequently, the biomimetic nanoformulation loaded with low doses of PLB and DIH achieved significantly longer survival of HCC mice, without causing toxic signs. Our study demonstrates a promising strategy for remodeling the immunosuppressive TME of liver cancer.

A cyclodextrin-based nanoformulation achieves co-delivery of ginsenoside Rg3 and quercetin for chemo-immunotherapy in colorectal cancer.

The immune checkpoint blockade therapy has profoundly revolutionized the field of cancer immunotherapy. However, despite great promise for a variety of cancers, the efficacy of immune checkpoint inhibitors is still low in colorectal cancer (CRC). This is mainly due to the immunosuppressive feature of the tumor microenvironment (TME). Emerging evidence reveals that certain chemotherapeutic drugs induce immunogenic cell death (ICD), demonstrating great potential for remodeling the immunosuppressive TME. In this study, the potential of ginsenoside Rg3 (Rg3) as an ICD inducer against CRC cells was confirmed using in vitro and in vivo experimental approaches. The ICD efficacy of Rg3 could be significantly enhanced by quercetin (QTN) that elicited reactive oxygen species (ROS). To ameliorate in vivo delivery barriers associated with chemotherapeutic drugs, a folate (FA)-targeted polyethylene glycol (PEG)-modified amphiphilic cyclodextrin nanoparticle (NP) was developed for co-encapsulation of Rg3 and QTN. The resultant nanoformulation (CD-PEG-FA.Rg3.QTN) significantly prolonged blood circulation and enhanced tumor targeting in an orthotopic CRC mouse model, resulting in the conversion of immunosuppressive TME. Furthermore, the CD-PEG-FA.Rg3.QTN achieved significantly longer survival of animals in combination with Anti-PD-L1. The study provides a promising strategy for the treatment of CRC.

Significance of belowground production to the long-term carbon sequestration of intertidal seagrass beds.

The high biomass and sediment features of seagrass beds can make their belowground portions critical sources of blue carbon sinks. However, seagrass belowground production and decomposition have rarely been quantified in the field. To assess the significance of seagrass belowground production to carbon sequestration, belowground carbon budgets were constructed in intertidal seagrass beds of the late-successional species Thalassia hemprichii and the early-successional species Haloduleuninervis in southern Taiwan. For both species, the turnover rates of the belowground portions were much longer than that of the aboveground portion, so the belowground biomass was much higher than the aboveground biomass. The leaf productivity of both species was significantly higher than the belowground productivity, but most of the leaf production decomposed within a year. The lower turnover and slower decomposition rates of the belowground portions allowed the late-successional seagrass T. hemprichii to store more carbon in the sediments than the early-successional seagrass H. uninervis. Long-term changes for the past 20 years in the sediment depth showed that the sediments of seagrass beds were increasing in the habitats at low elevation but were decreasing or had no clear trends in the habitats at high elevation or on the windward side. The carbon storage rates according to the belowground production of T. hemprichii and H. uninervis were 0.3-4.7 and 1.5-2.3 g C m-2 yr-1, respectively, which can potentially contribute 53% of the long-term organic carbon storage in the low-elevation sediments.

A folate-targeted PEGylated cyclodextrin-based nanoformulation achieves co-delivery of docetaxel and siRNA for colorectal cancer.

Docetaxel (DTX) is a chemotherapeutic agent used for a range of cancers, but it has little activity against colorectal cancer (CRC). However, combination therapy with other therapeutic agents is a potential strategy to enhance the efficacy of DTX in CRC treatment. The nuclear factor-κB (NF-κB) signaling pathway is implicated in a variety of malignancies (e.g., CRC), and the blockade of NF-κB may increase the sensitivity of cancer cells to chemotherapy. The application of small interference RNA (siRNA) to inhibit the translation of complementary mRNA has demonstrated the potential for cancer gene therapy. In this study, an amphiphilic cationic cyclodextrin (CD) nanoparticle modified with PEGylated folate (FA; a ligand to target folate receptor on CRC) has been developed for co-delivery of DTX and siRNA (against the RelA, a subunit of NF-κB) in the treatment of CRC. The resultant co-formulation (CD.DTX.siRelA.PEG-FA) achieved cell-specific uptake indicating the function of the folate targeting ligand. The CD.DTX.siRelA.PEG-FA nanoparticle enhanced the apoptotic effect of DTX with the downregulation of RelA expression, which significantly retarded the growth of CRC in mice, without causing significant toxicity. These results suggest that the FA-targeted PEGylated CD-based co-formulation provides a promising strategy for combining DTX and siRNA in treating CRC.

Two nanoformulations induce reactive oxygen species and immunogenetic cell death for synergistic chemo-immunotherapy eradicating colorectal cancer and hepatocellular carcinoma.

BACKGROUND: FOLFOX is a combinational regimen of folinic acid (FnA, FOL), fluorouracil (5-Fu, F) and oxaliplatin (OxP, OX), and has been long considered as the standard treatment of colorectal cancer (CRC) and hepatocellular carcinoma (HCC). Recent developments of nano delivery systems have provided profound promise for improving anticancer efficacy and alleviating side effects of FOLFOX. Previously, a nanoformulation (termed Nano-Folox) containing OxP derivative and FnA was developed in our laboratory using nanoprecipitation technique. Nano-Folox induced OxP-mediated immunogenic cell death (ICD)-associated antitumor immunity, which significantly suppressed tumor growth in the orthotopic CRC mouse model when administrated in combination with free 5-Fu. METHODS: A nanoformulation (termed Nano-FdUMP) containing FdUMP (5-Fu active metabolite) was newly developed using nanoprecipitation technique and used in combination with Nano-Folox for CRC and HCC therapies. RESULTS: Synergistic efficacy was achieved in orthotopic CRC and HCC mouse models. It resulted mainly from the fact that Nano-FdUMP mediated the formation of reactive oxygen species (ROS), which promoted the efficacy of ICD elicited by Nano-Folox. In addition, combination of Nano-Folox/Nano-FdUMP and anti-PD-L1 antibody significantly inhibited CRC liver metastasis, leading to long-term survival in mice. CONCLUSION: This study provides proof of concept that combination of two nano delivery systems can result in successful FOLFOX-associated CRC and HCC therapies. Further optimization in terms of dosing and timing will enhance clinical potential of this combination strategy for patients.

Role of Hyaluronic Acids and Potential as Regenerative Biomaterials in Wound Healing.

The skin can protect the body from external harm, sense environmental changes, and maintain physiological homeostasis. Cutaneous repair and regeneration associated with surgical wounds, acute traumas, and chronic diseases are a central concern of healthcare. Patients may experience the failure of current treatments due to the complexity of the healing process; therefore, emerging strategies are needed. Hyaluronic acids (HAs, also known as hyaluronan), a glycosaminoglycan (GAG) of the extracellular matrix (ECM), play key roles in cell differentiation, proliferation, and migration throughout tissue development and regeneration. Recently, HA derivatives have been developed as regenerative biomaterials for treating skin damage and injury. In this review, the healing process, namely, hemostasis, inflammation, proliferation, and maturation, is described and the role of HAs in the healing process is discussed. This review also provides recent examples in the development of HA derivatives for wound healing.

A Low Molecular Weight Hyaluronic Acid Derivative Accelerates Excisional Wound Healing by Modulating Pro-Inflammation, Promoting Epithelialization and Neovascularization, and Remodeling Collagen.

Recent knowledge of the cellular and molecular mechanisms underlying cutaneous wound healing has advanced the development of medical products. However, patients still suffer from the failure of current treatments, due to the complexity of healing process and thus novel therapeutic approaches are urgently needed. Previously, our laboratories produced a range of low molecular weight hyaluronic acid (LMW-HA) fragments, where a proportion of the glucosamine moieties were chemically N-acyl substituted. Specifically, N-butyrylation results in anti-inflammatory properties in a macrophage system, and we demonstrate the importance of N-acyl substituents in modulating the inflammatory response of LMW-HA. We have set up an inter-institutional collaborative program to examine the biomedical applications of the N-butyrylated LMW-HA (BHA). In this study, the potentials of BHA for dermal healing are assessed in vitro and in vivo. Consequently, BHA significantly promotes dermal healing relative to a commercial wound care product. By contrast, the "parent" partially de-acetylated LMW-HA (DHA) and the re-acetylated DHA (AHA) significantly delays wound closure, demonstrating the specificity of this N-acylation of LMW-HA in wound healing. Mechanistic studies reveal that the BHA-mediated therapeutic effect is achieved by targeting three phases of wound healing (i.e., inflammation, proliferation and maturation), demonstrating the significant potential of BHA for clinical translation in cutaneous wound healing.

Development of anisamide-targeted PEGylated gold nanorods to deliver epirubicin for chemo-photothermal therapy in tumor-bearing mice.

BACKGROUND: Gold nanorods (AuNRs), due to the optical and electronic properties namely the surface plasma resonance, have been developed to achieve the light-mediated photothermal therapy (PTT) for cancer. However, PTT alone may suffer from inefficient tumor killing. Recently, the combination of PTT and chemotherapy has been utilized to achieve synergistic anticancer effects. METHODS: In this study, AuNRs capped with hexadecyltrimethylammonium bromide (CTAB), poly(acrylic acid) (PAA), and PEGylated anisamide (a ligand known to target the sigma receptor) have been developed to produce a range of negatively charged anisamide-targeted PEGylated AuNRs (namely Au-CTAB-PAA-PEG-AA) for the combination of PTT and chemotherapy (termed as chemo-photothermal therapy [CPTT]). Epirubicin (EPI, an anthracycline drug) was efficiently loaded onto the surface of Au800-CTAB-PAA-PEG-AA via the electrostatic interaction forming Au800-CTAB-PAA-PEG-AA.EPI complex. RESULTS: The resultant complex demonstrated pH-dependent drug release, facilitated nucleus trafficking of EPI, and induced antiproliferative effects in human prostate cancer PC-3 cells. When Au800-CTAB-PAA-PEG-AA.EPI complex was further stimulated with desired laser irradiation, the synergistic outcome was evident in PC-3 xenograft mice. CONCLUSION: These results demonstrate a promising strategy for clinical application of CPTT in cancer.

Anisamide-targeted PEGylated gold nanoparticles designed to target prostate cancer mediate: Enhanced systemic exposure of siRNA, tumour growth suppression and a synergistic therapeutic response in combination with paclitaxel in mice.

Small interfering RNA (siRNA) has recently illustrated therapeutic potential for malignant disorders. However, the clinical application of siRNA-based therapeutics is significantly retarded by the paucity of successful delivery systems. Recently, multifunctional gold nanoparticles (AuNPs) as non-viral delivery carriers have shown promise for transporting chemotherapeutics, proteins/peptides, and genes. In this study, AuNPs capped with polyethylenimine (PEI) and PEGylated anisamide (a ligand known to target the sigma receptor) have been developed to produce a range of positively charged anisamide-targeted PEGylated AuNPs (namely Au-PEI-PEG-AA). The anisamide-targeted AuNPs effectively complexed siRNA via electrostatic interaction, and the resultant complex (Au110-PEI-PEG5000-AA.siRNA) illustrated favourable physicochemical characteristics, including particle size, surface charge, and stability. In vitro, anisamide-targeted AuNPs selectively bound to human prostate cancer PC-3 cells, inducing efficient endosomal escape of siRNA, and effective downregulation of the RelA gene. In vivo, prolonged systemic exposure of siRNA was achieved by anisamide-targeted AuNPs resulting in significant tumour growth suppression in a PC3 xenograft mouse model without an increase in toxicity. In addition, a combination of siRNA-mediated NF-κB knockdown using anisamide-targeted AuNPs with Paclitaxel produced a synergistic therapeutic response, thus providing a promising therapeutic strategy for the treatment of prostate cancer.