Epigallocatechin-3-gallate promotes wound healing response in diabetic mice by activating keratinocytes and promoting re-epithelialization.

Type 2 diabetes (T2D) is a metabolic disorder that causes numerous complications including impaired wound healing and poses a significant challenge for the management of diabetic patients. Epigallocatechin-3-gallate (EGCG) is a natural polyphenol that exhibits anti-inflammatory and anti-oxidative benefits in skin wounds, however, the direct effect of EGCG on epidermal keratinocytes, the primary cells required for re-epithelialization in wound healing remains unknown. Our study aims to examine the underlying mechanisms of EGCG's ability to promote re-epithelialization and wound healing in T2D-induced wounds. Murine models of wound healing in T2D were established via feeding high-fat high-fructose diet (HFFD) and the creation of full-thickness wounds. Mice were administered daily with EGCG or vehicle to examine the wound healing response and underlying molecular mechanisms of EGCG's protective effects. Systemic administration of EGCG in T2D mice robustly accelerated the wound healing response following injury. EGCG induced nuclear translocation of nuclear factor erythroid 2-related factor 2 (NRF2) and promoted cytokeratin 16 (K16) expression to activate epidermal keratinocytes and robustly promoted re-epithelialization of wounds in diabetic mice. Further, EGCG demonstrated high binding affinity with Kelch-like ECH-associated protein 1 (KEAP1), thereby inhibiting KEAP1-mediated degradation of NRF2. Our findings provide important evidence that EGCG accelerates the wound healing response in diabetic mice by activating epidermal keratinocytes, thereby promoting re-epithelialization of wounds via K16/NRF2/KEAP1 signaling axis. These mechanistic insights into the protective effects of EGCG further suggest its therapeutic potential as a promising drug for treating chronic wounds in T2D.

Whole ß-glucan particle attenuates AOM/DSS-induced colorectal tumorigenesis in mice via inhibition of intestinal inflammation.

Yeast ß-glucan is a polysaccharide purified from the Saccharomyces cerevisiae cell wall, and its multiple biological activities are essential for immune regulation. However, the effect of ß-glucan on the intestinal immune response during colitis-associated colorectal cancer (CAC) is unclear. Here, we explore the possible role of ß-glucan in the development of CAC. Wild type (WT) mice with CAC induced by azoxmethane (AOM) and dextran sodium sulfate (DSS) had fewer tumors than untreated mice after oral ß-glucan because of increased antitumor dendritic cells (DCs) in the tumor microenvironment, resulting in more CD8+ T cells and the production of related cytokines. ß-glucan also increased resistance to DSS-induced chronic colitis by reshaping the inflammatory microenvironment. These data suggest that ß-glucan improves experimental intestinal inflammation and delays the development of CAC. Therefore, ß-glucan is feasible for treating chronic colitis and CAC in clinical practice.

ß-Glucan Combined With PD-1/PD-L1 Checkpoint Blockade for Immunotherapy in Patients With Advanced Cancer.

Programmed death-1 (PD-1)/PD-ligand 1 (PD-L1) checkpoint blocking antibodies have been shown to be a powerful immune checkpoint blockade (ICB) therapy for patients with cancer. However, patients quickly develop resistance to immunotherapy. ß-glucan, an immune adjuvant, has been found to stimulate innate and adaptive immune responses. In this study, we assessed the use of whole glucan particle (WGP) ß-glucan in combination with PD-1/PD-L1-blocking antibodies to slow down the resistance to immunotherapy. Results from a tumor mouse model demonstrated that administration of WGP ß-glucan plus PD-1/PD-L1-blocking antibodies led to increased recruitment of immune-associated cells, improved regulation of the balance between T-cell activation and immune tolerance, and delayed tumor progression. This combination therapy was also found to improve progression-free survival in patients with advanced cancer who had previously discontinued anti-PD-1/PD-L1 because of disease progression. These findings suggest that ß-glucan could be used as an immune adjuvant to reverse anti-PD-1/PD-L1 resistance by regulating the immune system.

Babao Dan is a robust anti-tumor agent via inhibiting wnt/ß-catenin activation and cancer cell stemness.

ETHNOPHARMACOLOGICAL RELEVANCE: Traditional Chinese Medicine (TCM) is being increasingly used worldwide due to its diverse efficacy and relatively low side effects. Babao Dan (BBD) is a well-known TCM formula that is currently used for the effective treatment of various cancers, however its underlying molecular mechanism remains unknown. AIM OF THE STUDY: Tumor growth and tumor recurrence are characterized by two distinct populations of cells, namely the well-differentiated cancer cells composing the majority of tumor bulk, and cancer stem cells (CSCs) involved in tumor relapse, which are both strongly associated with excessive activation of Wnt/ß-catenin signaling. Our study aims to elucidate the underlying molecular mechanisms associated with the anti-tumor proliferative effects of Babao Dan (BBD). MATERIALS AND METHODS: We used a hepatoblastoma cell line HepG2 with stem cell-like traits that harbors a constitutively active mutant of ß-catenin in order to study the anti-tumor ability of BBD via targeting Wnt/ß-catenin signaling. RESULTS: BBD robustly attenuated both the intrinsic and extrinsic activation of Wnt/ß-catenin pathway in HepG2 hepatoblastoma cells, as well as Wnt target genes. Moreover, BBD significantly inhibited both the proliferation of well-differentiated cancer cells, as well as the stem-like property of CSCs as evidenced by EpCAM, a Wnt target gene and a novel marker of cancer cell stemness. In addition, mice administered with BBD using HepG2 cell line derived xenograft model had marked reductions in tumor size and weight, as well as significantly decreased expressions of Wnt target genes and cancer cell stemness. CONCLUSION: Our findings elucidated the underlying molecular mechanisms associated with the robust anti-tumor effects of BBD via potent inhibition of Wnt/ß-catenin signaling, and implicate its use in the clinical treatment of cancers.

HDAC9 deficiency promotes tumor progression by decreasing the CD8+ dendritic cell infiltration of the tumor microenvironment.

BACKGROUND: The tumor microenvironment (TME) contains a variety of immune cells, which play critical roles during the multistep development of tumors. Histone deacetylase 9 (HDAC9) has been reported to have either proinflammatory or anti-inflammatory effects, depending on the immune environment. In this study, we investigated whether HDAC9 in the tumor stroma regulated inflammation and antitumor immunity. METHODS: Hdac9 knockout mice were generated to analyze the HDAC9-associated inflammation and tumor progression. Immune cells and cytokines in TME or draining lymph nodes were quantified by flow cytometry and quantitative reverse transcription-PCR. The antigen presentation and CD8+ T cell priming by tumor-infiltrating dendritic cells (DCs) were evaluated in vitro and in vivo. HDAC9-associated inflammation was investigated in a mouse model with dextran sulfate sodium-induced colitis. Correlation of HDAC9 with CD8+ expression was assessed in tissue sections from patients with non-small cell lung cancer. RESULTS: HDAC9 deficiency promoted tumor progression by decreasing the CD8+ DC infiltration of the TME. Compared with wild-type mice, the tumor-infiltrating DCs of Hdac9-/- mice displayed impaired cross-presentation of tumor antigens and cross-priming of CD8+ T cells. Moreover, HDAC9 expression was significantly positively correlated with CD8+ cell counts in human lung cancer stroma samples. CONCLUSIONS: HDAC9 deficiency decreased inflammation and promoted tumor progression by decreasing CD8+ DC infiltration of the TME. HDAC9 expression in the tumor stroma may represent a promising biomarker to predict the therapeutic responses of patients receiving CD8+ T cell-dependent immune treatment regimens.

Key genes and pathways in tumor-educated dendritic cells by bioinformatical analysis.

Specific tumor microenvironment signaling might prevent the maturation of dendritic cells (DCs) with tolerogenic and immunosuppressive potential accounting for antigen-specific unresponsiveness in the lymphoid organs and in the periphery. In the present study, dendritic cells treated with LLC lung cancer cell or 4T1 breast cancer cell culture supernatants significantly down-regulated the expression of co-stimulatory molecules MHC-II, CD40, CD80, but up-regulated the inhibitory molecule PD-L1/L2, VISTA, and increased the messengerRNA levels of interleukin (IL)-6, arginase I, and IL-10, but decreased tumor necrosis factor-α and IL-12a. RNA was isolated from the dendritic cells with or without tumor supernatant stimulation and RNA sequencing was done. Then the differential expression genes were sorted, the candidate genes were analyzed and pathway enrichment analysis was done, and the associated protein-protein interaction network (PPI) was established. After integrated bioinformatical analysis, 405 (279 up-regulated and 126 down-regulated) consistently differential expression genes were identified. Using gene ontology and pathway analysis, it was found that differential expression genes were mainly enriched in the immune response, cell-cell interaction, hemostasis, and cell surface interactions with the vascular wall. The PPI data demonstrated that 236 nodes were classified with 1072 edges, and the most remarkable three modules involved 53 central node genes associated with cell survival, cell-substrate adhesion, chemotaxis, migration, immune response, and complement receptor mediated signaling pathway. These findings revealed the immune status of dendritic cells in the tumor environment.

ß-Glucan induces autophagy in dendritic cells and influences T-cell differentiation.

ß-Glucan has been reported to activate dendritic cells (DCs), and activated DCs, subsequently, promote Th1 and cytotoxic T-lymphocyte priming and differentiation in vitro. However, the mechanism that regulates the immune response of ß-glucan-induced DCs has not been thoroughly elucidated to date. Recent studies have drawn attention to a strong relationship between pathogen-associated molecular patterns (PAMP) recognition and autophagy for the activation of DC function. In this study, we observed that ß-glucan induced the expression of a number of autophagy-related genes and the formation of autophagosomes in DCs. To further investigate whether ß-glucan-induced DC activation and innate cytokine production are associated with autophagy, we utilized 3-MA to block autophagosome formation and accessed the maturation and function of DCs induced by ß-glucan. We found that autophagy-deficient DCs showed downregulated expression of MHC-II and CD80, decreased TNF-α secretion, and reduced production of iNOS upon ß-glucan stimulation. Further examination demonstrated that blockade of autophagy in ß-glucan-induced DCs significantly attenuated IFN-γ production by co-cultured CD4 + T cells and inhibited the proliferation and differentiation of CD4 + T cells. Thus, these data indicate that autophagy in ß-glucan-induced DCs is a crucial mechanism for the maturation of DCs, and it drives innate cytokine production, thereby facilitating adaptive immune responses.

Tumor exosomes block dendritic cells maturation to decrease the T cell immune response.

Tumors can induce the generation and accumulation of immunosuppression in a tumor microenvironment, contributing to the tumor's escape from immunological surveillance. Although tumor antigen-pulsed dendritic cell can improve anti-tumor immune responses, tumor associated regulatory dendritic cells are involved in the induction of immune tolerance. The current study sought to investigate whether exosomes produced by tumor cells had any effect on DCs in immune suppression. In this study, we examined the effect of tumor exosomes on DCs and found that exosomes from LLC Lewis lung carcinoma or 4T1 breast cancer cell blocked the differentiation of myeloid precursor cells into CD11c+ DCs and induced cell apoptosis. Tumor exosome treatment inhibited the maturation and migration of DCs and promoted the immune suppression of DCs. The treatment of tumor exosomes drastically decreased CD4+IFN-γ+ Th1 differentiation but increased the rates of regulatory T (Treg) cells. The immunosuppressive ability of tumor exosome-treated DCs were partially restored with PD-L1 blockage. These data suggested that PD-L1 played a role in tumor exosome-induced DC-associated immune suppression.

[Guanylate-binding protein 2 regulates the maturation of mouse dendritic cells induced by ß-glucan].

Objective To investigate the effect of guanylate-binding protein 2 (GBP2) on ß-glucan-induced maturation and immune response of dendritic cells (DCs). Methods RNA-microarray and real time quantitative PCR were used to investigate the change of genes in DCs induced by ß-glucan. Thereafter, DCs were transfected with GBP2 siRNA to knock down the expression of GBP2. Flow cytometry was used to detect the surface markers (CD11c, MHC-II, CD80) on DCs as well as the proliferation of T cells. Cytokines (IL-6, IL-12p70, TNF-α, IL-10) were tested by ELISA. Results The expressions of DC surface markers, including CD11c, MHC- II, CD80, were significantly down-regulated after the cells were transfected with GBP2 siRNA. Moreover, the production of IL-6, IL-12 and TNF-α were also depressed. OVA specific T-cell proliferation decreased when OT-II T cells were co-cultured with GBP2-siRNA transfected-DCs. Conclusion GBP2 can effectively regulate ß-glucan-induced maturation of DCs, thus suppressing the proliferation of T cells.

[Whole glucan particle promotes the maturation of tumor-educated mouse dendritic cells to suppress regulatory T cell differentiation].

Objective To investigate the maturation and immune responses of tumor-educated dendritic cells (TEDCs) stimulated by whole glucan particle (WGP). Methods Mouse bone marrow-derived dendritic cells were generated by Flt3 ligand and co-cultured with interleukin 10 (IL-10) and transforming growth factor ß (TGF-ß) in vitro to induce TEDCs, and then stimulated by WGP for 2 days. CD4+ FOXP3+ T cells from the lymph nodes and spleens of OT-II mice were purified by magnetic-activated cell sorting, and then co-cultured with TEDCs in the presence of ovalbumin (OVA). Expressions of cell surface markers (CD11c, CD86, CD40, CD80, MHC-II) and CD4+ FOXP3+T cell differentiation and proliferation were detected by flow cytometry. real-time quantitative PCR was used to detect the mRNA levels of TNF-α, IL-12p40, IL-10, IL-6, IL-4, TGF-ß1 and ELISA was used to detect the levels of TNF-α, IL-23, IL-12p70, IL-4 in culture supernatant. Results WGP up-regulated MHC-II and co-stimulation molecules CD86, CD80, CD40 on TEDCs, increased the levels of TNF-α, IL-12p40, IL-6 in TEDCs, decreased the production of TGF-ß1. Furthermore, WGP also suppressed CD4+FOXP3+ T cell differentiation and proliferation in vitro. Conclusion WGP improves TEDC maturation and inhibits immunosuppressive functions.

ß-glucan restores tumor-educated dendritic cell maturation to enhance antitumor immune responses.

Tumors can induce the generation and accumulation of immunosuppressive cells such as myeloid-derived suppressor cells (MDSCs) in a tumor microenvironment, contributing to tumor escape from immunological attack. Although dendritic cell-based cancer vaccines can initiate antitumor immune responses, tumor-educated dendritic cells (TEDCs) involved in the tolerance induction have attracted much attention recently. In this study, we investigated the effect of ß-glucan on TEDCs and found that ß-glucan treatment could promote the maturation and migration of TEDCs and that the suppressive function of TEDCs was significantly decreased. Treatment with ß-glucan drastically decreased the levels of regulatory T (Treg) cells but increased the infiltration of macrophages, granulocytes and DCs in tumor masses, thus elicited Th1 differentiation and cytotoxic T-lymphocyte responses and led to a delay in tumor progression. These findings reveal that ß-glucan can inhibit the regulatory function of TEDCs, therefore revealing a novel function for ß-glucan in immunotherapy and suggesting its potential clinical benefit. ß-Glucan directly abrogated tumor-educated dendritic cells-associated immune suppression, promoted Th1 differentiation and cytotoxic T-lymphocyte priming and improved antitumor responses.

[ß-Glucan promotes the maturation and migration of bone marrow-derived dendritic cells].

OBJECTIVE: To investigate the effects of ß-glucan on the maturation and migration of bone marrow-derived dendritic cells (BMDCs). METHODS: BMDCs were isolated from mouse bone marrow cells in vitro and induced by ß-glucan for maturation. The expressions of cell surface markers were detected by flow cytometry (FCM). The cytokines (IL-6, IL-12p40, tumor necrosis factor α) in the supernatants were measured by ELISA, and the expressions of intracellular CC chemokine receptor 1 (CCR1), CCR2, CCR5, CCR7 were determined by real-time quantitative PCR. Furthermore, the chemotactic response to CC chemokine ligand 19 (CCLl9) and CCL21, i.e. CCR7-1igands, was measured by Transwell(TM) migration assay. Moreover, the number of migrated cells in the draining lymph nodes was analyzed by FCM. RESULTS: Compared with the control group, the expressions of co-stimulation molecules (MHC II, CD40, CD80, CD86) on BMDCs were up-regulated in the presence of ß-glucan. Furthermore, ß-glucan could prompt BMDCs to secret high levels of IL-6, TNF-α, IL-12 p40 and increase the production of CCR7 mRNA. After ß-glucan treatment, BMDCs were more sensitive to CCL19/CCL21. The number of BMDCs migrated from subcutaneous injection site into the draining lymph nodes significantly increased in ß-glucan group. CONCLUSION: ß-glucan can promote the maturation of BMDCs and enhance the migration ability of BMDCs in vitro and in vivo.

MiR-124 inhibits cell proliferation in breast cancer through downregulation of CDK4.

Studies have shown that microRNAs (miRNAs) are involved in the malignant progression of human cancer. However, little is known about the potential role of miRNAs in breast carcinogenesis. miR-124 expression in breast cancer tissue was measured by quantitative real-time PCR (qRT-PCR). Target prediction algorithms and luciferase reporter gene assays were used to investigate the target of miR-124. Breast cancer cells growth was regulated by overexpression or knockdown miR-124. At the end of the study, tumor-bearing mice were tested to confirm the function of miR-124 in breast cancer. In this study, we demonstrated that the expression of miR-124 was significantly downregulated in breast cancer tissues compared with matched adjacent non-neoplastic tissues. We identified and confirmed that cyclin-dependent kinase 4 (CDK4) was a direct target of miR-124. Overexpression of miR-124 suppressed CDK4 protein expression and attenuated cell viability, proliferation, and cell cycle progression in MCF-7 and MDA-MB-435S breast cancer cells in vitro. Overexpression of CDK4 partially rescued the inhibitory effect of miR-124 in the breast cancer cells. Moreover, we found that miR-124 overexpression effectively repressed tumor growth in xenograft animal experiments. Our results demonstrate that miR-124 functions as a growth-suppressive miRNA and plays an important role in inhibiting tumorigenesis by targeting CDK4.

ß-Glucan enhances cytotoxic T lymphocyte responses by activation of human monocyte-derived dendritic cells via the PI3K/AKT pathway.

PURPOSE: To investigate the effects of ß-(1,3/1,6)-d-glucan on dendritic cells (DCs) maturation, cytotoxic T lymphocyte responses and the molecular mechanisms of its transition. METHODS AND RESULTS: Human monocyte-derived DCs were matured using yeast-derived particulate ß-glucan (WGP) or a mix of TNF-α, IL-1ß and IL-6 ("Conv mix"). Multicolor flow cytometry was used to study the DCs phenotype and cytotoxic T-lymphocyte priming and differentiation. ELISA and RT-PCR assays were used to evaluate cytokine production. Western blot was used to investigate the signal pathways. WGP-matured DCs functions were compared with those of Conv mix-matured DCs. WGP-matured DCs expressed higher levels of CD11c, CD86, CD40 and HLA-DR; produced higher levels of pro-inflammatory cytokines; and elicited more CTL priming and differentiation than Conv mix-matured DCs. The PI3K/AKT signaling pathway was involved in WGP-induced dendritic cell maturation. Furthermore, WGP-matured DCs significantly increased tumor-specific CTL responses. CONCLUSION: Excellent ability of yeast-derived particulate ß-glucan to induce DCs maturation and tumor-specific CTL responses explains, in part, its clinical benefits and emphasizes its utility in ex vivo maturation of DCs generated for therapy.

Autologous dendritic cell vaccine for estrogen receptor (ER)/progestin receptor (PR) double-negative breast cancer.

PURPOSE: A wealth of preclinical information, as well as a modest amount of clinical information, indicates that dendritic cell vaccines have therapeutic potential. The aim of this work was to assess the immune response, disease progression, and post-treatment survival of ER/PR double-negative stage II/IIIA breast cancer patients vaccinated with autologous dendritic cells pulsed with autologous tumor lysates. METHODS: Dendritic cell (DC) vaccines were generated from CD14+ precursors pulsed with autologous tumor lysates. DCs were matured with defined factors that induced surface marker and cytokine production. Individuals were immunized intradermally four times. Specific delayed type IV hypersensitivity (DTH) reaction, ex vivo cytokine production, and lymphocyte subsets were determined for the evaluation of the therapeutic efficiency. Overall survival and disease progression rates were analyzed using Kaplan­Meier curves and compared with those of contemporaneous patients who were not administered DC vaccines. RESULTS: There were no unanticipated or serious adverse effects. DC vaccines elicited Th1 cytokine secretion and increased NK cells, CD8+ IFN-+ cells but decreased the percentage of CD3+ T cells and CD3+ HLA-DR+ T cells in the peripheral blood. Approximately 58% (18/31) of patients had a DTH-positive reaction. There was no difference in overall survival between the patients with and without DC vaccine. The 3-year progression-free survival was significantly prolonged: 76.9% versus 31.0% (with vs. without DC vaccine, p < 0.05). CONCLUSION: Our findings strongly suggest that tumor lysate-pulsed DCs provide a standardized and widely applicable source of breast cancer antigens that are very effective in evoking anti-breast cancer immune responses.

The predictive value of epidermal growth factor receptor expression for sensitivity to vinorelbine in breast cancer.

Breast cancer patients with positive epidermal growth factor receptor (EGFR) expression have significantly worse post-relapse prognosis than patients with negative EGFR expression. Vinorelbine (NVB) is usually reserved as a salvage therapy after anthracyclines and taxanes in patients with breast cancer. To see whether EGFR expression has a predictive value in NVB-mediated effect on human breast cancer cells, we examined 50 primary breast cancer samples. Of these, 42% were found to be NVB sensitive by ATP-tumour chemosensitivity assay. Sensitivity was correlated with EGFR expression level (p = 0.001). To dynamically examine EGFR's effect on NVB sensitivity in breast cancer cells, we used the real-time cell electronic sensing system with EGFR-positive and EGFR-negative breast cancer cell lines, MCF-7 and MDA-MB-435s, respectively. MCF-7 is NVB sensitive, while MDA-MB-435 is NVB resistant. NVB-induced cytotoxicity to MCF-7 can be partly reversed with inhibitory anti-EGFR antibody. NVB up-regulated EGFR expression in MCF-7 cells, which affects ERK1/2 phosphorylation. This cellular response mechanism may cause greater input to non-lethally damaged cells. These data suggest that EGFR expression can be used as a prognostic factor for breast cancer sensitivity to NVB, which could help identify appropriate treatments for breast cancer.

Ligation or cross-linking of CD40 has different effects on AGS gastric cancer cells.

A gastric cancer (GC) cell line, AGS, has high-level expression of CD40, a tumor necrosis factor receptor (TNFR) family member. CD40 is present on the surfaces of a large variety of cells, including B cells, endothelial cells, dendritic cells and some carcinoma cells, and delivers signals regulating diverse cellular responses, such as proliferation, differentiation, growth suppression, and cell death. In this research, we studied the effects of different forms of CD40 stimulation on AGS cells by flow cytometry, Western blotting and siRNA transfection. We found that different forms of CD40 stimulation, either recombinant soluble CD40L (sCD40L, ligation) or agonist anti-CD40 antibody (cross-linking), induced different effects in AGS gastric cancer cells, proliferation or apoptosis. We also showed that VEGF provided a significant contribution to sCD40L-induced proliferation, while agonist anti-CD40 antibody induced GADD45 upregulation and promoted apoptosis.

In vitro chemosensitivity in breast cancer using ATP-tumor chemosensitivity assay.

Chemotherapy for breast cancer is given on the basis of empirical information from clinical trials, an approach which falls to take into account the known heterogeneity of chemosensitivity between patients. This study aimed to demonstrate the degree of heterogeneity of chemosensitivity in breast cancers. In this study, we examined the heterogeneity of chemosensitivity in breast cancer specimens (n = 50) using an ex vivo ATP-tumor chemosensitivity assay (ATP-TCA). Assay evaluability was 92% in surgical biopsies or pleural aspirates. A variety of chemosensitivity agents were tested. We found that the most active single agent tested was paclitaxel, to which 65.9% of samples were sensitive. Combinations of agents also showed more strong sensitivity cases. The Adriamycin+5-FU demonstrated a strong sensitivity in 23 of 43 (52.3%) of samples. Adriamycin+paclitaxel was more effective, with strong sensitivity in 37 of 43 cases tested (86.0%). There was a marked heterogeneity of chemosensitivity in breast cancer. Chemosensitivity testing may provide a practical method of testing new regimens before clinical trials in breast cancer patients.