Induction of Immune Responses and Phosphatidylserine Exposure by TLR9 Activation Results in a Cooperative Antitumor Effect with a Phosphatidylserine-targeting Prodrug.

Head and neck cancer is a major cancer type, with high motility rates that reduce the quality of life of patients. Herein, we investigated the effectiveness and mechanism of a combination therapy involving TLR9 activator (CpG-2722) and phosphatidylserine (PS)-targeting prodrug of SN38 (BPRDP056) in a syngeneic orthotopic head and neck cancer animal model. The results showed a cooperative antitumor effect of CpG-2722 and BPRDP056 owing to their distinct and complementary antitumor functions. CpG-2722 induced antitumor immune responses, including dendritic cell maturation, cytokine production, and immune cell accumulation in tumors, whereas BPRDP056 directly exerted cytotoxicity toward cancer cells. We also discovered a novel function and mechanism of TLR9 activation, which increased PS exposure on cancer cells, thereby attracting more BPRDP056 to the tumor site for cancer cell killing. Killed cells expose more PS in tumor for BPRDP056 targeting. Tumor antigens released from the dead cells were taken up by antigen-presenting cells, which enhanced the CpG-272-promoted T cell-mediated tumor-killing effect. These form a positive feed-forward antitumor effect between the actions of CpG-2722 and BPRDP056. Thus, the study findings suggest a novel strategy of utilizing the PS-inducing function of TLR9 agonists to develop combinational cancer treatments using PS-targeting drugs.

Generation and Characterization of Single Chain Variable Fragment against Alpha-Enolase of Candida albicans.

Candida albicans (C. albicans) is an opportunistic human pathogen responsible for approximately a half of clinical candidemia. The emerging Candida spp. with resistance to azoles is a major challenge in clinic, suggesting an urgent demand for new drugs and therapeutic strategies. Alpha-enolase (Eno1) is a multifunctional protein and represents an important marker for invasive candidiasis. Thus, C. albicans Eno1 (CaEno1) is believed to be an important target for the development of therapeutic agents and antibody drugs. Recombinant CaEno1 (rCaEno1) was first used to immunize chickens. Subsequently, we used phage display technology to construct two single chain variable fragment (scFv) antibody libraries. A novel biopanning procedure was carried out to screen anti-rCaEno1 scFv antibodies, whose specificities were further characterized. The polyclonal IgY antibodies showed binding to rCaEno1 and native CaEno1. A dominant scFv (CaS1) and its properties were further characterized. CaS1 attenuated the growth of C. albicans and inhibited the binding of CaEno1 to plasminogen. Animal studies showed that CaS1 prolonged the survival rate of mice and zebrafish with candidiasis. The fungal burden in kidney and spleen, as well as level of inflammatory cytokines were significantly reduced in CaS1-treated mice. These results suggest CaS1 has potential of being immunotherapeutic drug against C. albicans infections.

Integrative Omics Analysis Reveals Soluble Cadherin-3 as a Survival Predictor and an Early Monitoring Marker of EGFR Tyrosine Kinase Inhibitor Therapy in Lung Cancer.

PURPOSE: EGFR tyrosine kinase inhibitors (EGFR-TKI) benefit patients with advanced lung adenocarcinoma (ADC) harboring activating EGFR mutations. We aimed to identify biomarkers to monitor and predict the progression of patients receiving EGFR-TKIs via a comprehensive omic analysis. EXPERIMENTAL DESIGN: We applied quantitative proteomics to generate the TKI resistance-associated pleural effusion (PE) proteome from patients with ADC with or without EGFR-TKI resistance. Candidates were selected from integrated genomic and proteomic datasets. The PE (n = 33) and serum (n = 329) levels of potential biomarkers were validated with ELISAs. Western blotting was applied to detect protein expression in tissues, PEs, and a cell line. Gene knockdown, TKI treatment, and proliferation assays were used to determine EGFR-TKI sensitivity. Progression-free survival (PFS) and overall survival (OS) were assessed to evaluate the prognostic values of the potential biomarkers. RESULTS: Fifteen proteins were identified as potential biomarkers of EGFR-TKI resistance. Cadherin-3 (CDH3) was overexpressed in ADC tissues compared with normal tissues. CDH3 knockdown enhanced EGFR-TKI sensitivity in ADC cells. The PE level of soluble CDH3 (sCDH3) was increased in patients with resistance. The altered sCDH3 serum level reflected the efficacy of EGFR-TKI after 1 month of treatment (n = 43). Baseline sCDH3 was significantly associated with PFS and OS in patients with ADC after EGFR-TKI therapy (n = 76). Moreover, sCDH3 was positively associated with tumor stage in non-small cell lung cancer (n = 272). CONCLUSIONS: We provide useful marker candidates for drug resistance studies. sCDH3 is a survival predictor and real-time indicator of treatment efficacy in patients with ADC treated with EGFR-TKIs.

Inhibition of Alternative Cancer Cell Metabolism of EGFR Mutated Non-Small Cell Lung Cancer Serves as a Potential Therapeutic Strategy.

Targeted therapy is an efficient treatment for patients with epidermal growth factor receptor (EGFR) mutations in non-small cell lung cancer (NSCLC). Therapeutic resistance invariably occurs in NSCLC patients. Many studies have focused on drug resistance mechanisms, but only a few have addressed the metabolic flexibility in drug-resistant NSCLC. In the present study, we found that during the developing resistance to tyrosine kinase inhibitor (TKI), TKI-resistant NSCLC cells acquired metabolic flexibility in that they switched from dependence on glycolysis to oxidative phosphorylation by substantially increasing the activity of the mitochondria. Concurrently, we found the predominant expression of monocarboxylate transporter 1 (MCT-1) in the TKI-resistant NSCLC cells was strongly increased in those cells that oxidized lactate. Thus, we hypothesized that inhibiting MCT-1 could represent a novel treatment strategy. We treated cells with the MCT-1 inhibitor AZD3965. We found a significant decrease in cell proliferation and cell motility in TKI-sensitive and TKI-resistant cells. Taken together, these results demonstrated that gefitinib-resistant NSCLC cells harbored higher mitochondrial bioenergetics and MCT-1 expression. These results implied that targeting mitochondrial oxidative phosphorylation proteins or MCT-1 could serve as potential treatments for both TKI-sensitive and -resistant non-small cell lung cancer.

Valproic Acid and Lithium Meditate Anti-Inflammatory Effects by Differentially Modulating Dendritic Cell Differentiation and Function.

Valproic acid (VPA), with inhibition activity mainly toward histone deacetylase (HDAC) and Glycogen Synthase Kinase (GSK)-3, and lithium, with inhibition activity mainly toward GSK-3, are both prescribed in clinical as mood-stabilizers and anticonvulsants for the control of bipolar disorder. This study aims to compare the immuno-modulation activities of VPA and lithium, especially on the differentiation and functions of dendritic cells (DC). Our data show that treatment with VPA or lithium effectively alleviated the severity of collagen-induced arthritis triggered by LPS in mice. Both agents reduced the serum level of IL-6 and IL-10 after LPS challenge in mice. VPA and lithium both induce significant down-regulation of group I CD1 expression and secretion of IL-6 during differentiation of human monocyte-derived immature DC, while they differ in the induction of CD83 and CD86 expression, secretion of IL-8, IL-10, and TNF-α. Upon stimulation of immature DC with LPS, VPA, and lithium both reduced the secretion of IL-6 and TNF-α. However, only lithium significantly increased the production of IL-10, while VPA increased the production of IL-8 but substantially reduce the secretion of IL-10 and IL-23. Treatment with VPA resulted in a reduced capacity of LPS-stimulated DC to promote the differentiation of T helper 17 cells that are critical in the promotion of inflammatory responses. Taken together, our results suggest that VPA and lithium may differentially modulate inflammation through regulating the capacity of DC to mediate distinct T cell responses, and they may provide a complementary immunomodulatory effects for the treatment of inflammation-related diseases. J. Cell. Physiol. 232: 1176-1186, 2017. © 2016 Wiley Periodicals, Inc.

Antimutagenic constituents of adlay (Coix lachryma-jobi L. var. ma-yuen Stapf) with potential cancer chemopreventive activity.

Adlay has long been used in traditional Chinese medicine and as a nourishing food. The acetone extract of adlay hull had previously been demonstrated to possess potent antimutagenic activity. The aims of this study were to identify the antimutagenic constituents from adlay hull by using Ames antimutagenic activity-guide isolation procedures and to investigate their chemopreventive efficacies in cultured cells. The results demonstrated that six compounds showing great antimutagenic activity were identified by spectroscopic methods and by comparison with authentic samples to be p-hydroxybenzaldehyde, vanillin, syringaldehyde, trans-coniferylaldehyde, sinapaldehyde, and coixol. Two of them, trans-coniferylaldehyde and sinapaldehyde, exhibit relatively potent scavenging of DPPH radicals, inhibit TPA stimulated superoxide anion generation in neutrophil-like leukocytes, and induce Nrf2/ARE-driven luciferase activity in HSC-3 cells. Moreover, trans-coniferylaldehyde possesses cytoprotective efficacy against tert-butyl hydroperoxide-induced DNA double-strand breaks in cultured cells, and the chemopreventive potency induced by trans-coniferylaldehyde may be through the activation of kinase signals, including p38, ERK1/2, JNK, MEK1/2, and MSK1/2. In summary, we first identified six antimutagenic constituents from adlay hull. Among them, trans-coniferylaldehyde would be a highly promising agent for cancer chemoprevention and merits further investigation.

A novel adjuvant Ling Zhi-8 enhances the efficacy of DNA cancer vaccine by activating dendritic cells.

DNA vaccine has been suggested to use in cancer therapy, but the efficacy remains to be improved. The immunostimulatory effect of a fungal immunomodulatory protein Ling Zhi-8 (LZ-8) isolated from Ganoderma lucidum has been reported. In this study, we tested the adjuvanticity of LZ-8 for HER-2/neu DNA vaccine against p185(neu) expressing tumor MBT-2 in mice. We found that recombinant LZ-8 stimulated mouse bone marrow-derived dendritic cells (DCs) via TLR4 and its stimulatory effect was not due to any microbe contaminant. In addition, LZ-8 enhanced the ability of DCs to induce antigen-specific T cell activation in vitro and in a subunit vaccine model in vivo. Surprisingly, LZ-8 cotreatment strongly improved the therapeutic effect of DNA vaccine against MBT-2 tumor in mice. This increase in antitumor activity was attributed to the enhancement of vaccine-induced Th1 and CTL responses. Consistent with the results from DCs, the promoting effect of LZ-8 on DNA vaccine was diminished when the MBT-2 tumor cells were grown in TLR4 mutant mice. Thus, we concluded that LZ-8 may be a promising adjuvant to enhance the efficacy of DNA vaccine by activating DCs via TLR4.

Administration of polysaccharides from Antrodia camphorata modulates dendritic cell function and alleviates allergen-induced T helper type 2 responses in a mouse model of asthma.

Asthma is a chronic disease characterized by airway inflammation caused by the dysregulated production of cytokines secreted by allergen-specific type 2 T helper (Th2) cells. Antrodia camphorata is a commonly used fungus in Asian folk medicine, and A. camphorata polysaccharides are reported to possess anti-cancer activities. In this study, the immunomodulatory effects of purified fractionated polysaccharides (GF2) from A. camphorata on dendritic cells (DCs) and their potential preventive effects against ovalbumin (OVA) -induced asthma were investigated. In the presence of GF2, lipopolysaccharide (LPS) -activated DCs exhibited up-regulated expression of major histocompatibility complex (MHC) class II and co-stimulatory molecules, as well as enhanced interleukin-10 (IL-10) and IL-12 production. GF2 treatment on LPS-activated DCs suppressed naïve CD4(+) T-cell proliferation and Th2 cell polarization with IL-10 production in an allogeneic mixed lymphocyte reaction. In animal experiments, a high dose of GF2 efficiently reduced expression levels of OVA-specific immunoglobulin G1 (IgG1) and IgE. However, lower doses of GF2 significantly enhanced OVA-specific IgG2a production. Our data also showed that administration of GF2 dose-dependently inhibited the development of airway hyperresponsiveness, airway eosinophilia and Th2 responses. OVA-specific CD4(+) T cells from higher doses of GF2-treated mice had significantly lower proliferative capacities compared with control mice. Moreover, treatment with GF2 significantly increased the high levels of IL-10 and low levels of interferon-gamma produced by T cells. Taken together, these data indicate that administration of A. camphorata polysaccharides (GF2) may have therapeutic potential when used as an adjuvant for the immunomodulatory treatment of allergic asthma.