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these findings suggest that changing glutathione redox balance, increase in GSH level, and the GSH/GSSG ratio by γ-GCE, ameliorate bronchial asthma by altering the Th1/Th2 imbalance through IL-12 production from APC and suppressing chemokine production and eosinophil migration itself.

Bronchial asthma is a typical helper T cell type 2 (Th2) disease

Through the release of Th2 cytokines, such as IL-4, IL-5, and IL-13, orchestrate the recruitment and activation of the primary effector cells of the allergic response: the mast cells and the eosinophils

Glutathione is the most abundant nonprotein sulfhydryl compound in almost all cells. This tripeptide plays a significant role in many biological processes. It also constitutes the first line of the cellular defense mechanism against oxidative injury along with SOD, ascorbate, vitamin E, and catalase, and is the major intracellular redox buffer in ubiquitous cell types

We have shown that glutathione redox status, namely the balance between intracellular reduced (GSH) and oxidized (GSSG) glutathione, in murine antigen-presenting cells (APC) plays a central role in determining which of the reductive and oxidative APC predominate during immune status, and the balance between reductive and oxidative APC regulates Th1/Th2 balance through production of IL-12

we have also shown that exposure of human alveolar macrophages to the Th1 cytokine IFN-γ or the Th2 cytokine IL-4 either increases or decreases the GSH/GSSG ratio, respectively, which regulates Th1/Th2 balance through IL-12 production

the ability to generate a Th1 or Th2 type response has turned out to depend not only on T cells but also on the intracellular glutathione redox status of APC

Th1 cytokine IFN-γ and Th2 cytokine IL-4 increases and decreases the GSH/GSSG ratio, respectively, and that this ratio influences LPS-induced IL-12 production from alveolar macrophages

the ability to generate a Th1 or Th2 response is dependent on glutathione redox status of APC

administration of γ-GCE elevates GSH level and GSH/GSSG ratio in the lung, and ameliorates AHR and eosinophilic airway inflammation by altering the Th1/Th2 balance and suppressing chemokine production and eosinophil migration in a mouse asthma model

In normal embryogenesis and homeostasis, the canonical WNT pathway is activated by secreted WNT ligands produced in highly controlled context-dependent manners and in precise amounts. WNT activity is transduced in the cytoplasm, inactivates the APC destruction complex, and results in the translocation of activate β-CATENIN to the nucleus, where it cooperates with DNA-binding TCF/LEF factors to regulate WNT-TCF targets and the ensuing genomic response

beyond the loss of activity of the APC destruction complex, for instance throughAPC mutation, phosphorylation of β-CATENIN at C-terminal sites is required for the full activation of WNT-TCF signaling and the ensuing WNT-TCF responses in cancer.

The WNT-TCF response blockade that we describe for low doses of Ivermectin suggests an action independent to the deregulation of chloride channels

involve the repression of the levels of C-terminally phosphorylated β-CATENIN forms and of CYCLIN D1, a critical target that is an oncogene and positive cell cycle regulator.

the Avermectin single-molecule derivative Selamectin, a drug widely used in veterinarian medicine (Nolan & Lok, 2012), is ten times more potent acting in the nanomolar range

Ivermectin also diminished the protein levels of CYCLIN D1, a direct TCF target and oncogene, in both HT29 and H358 tumor cells

Activated Caspase3 was used as a marker of apoptosis by immunohistochemistry 48 h after drug treatment. Selamectin and Ivermectin induced up to a sevenfold increase in the number of activated Caspase3+ cells in two primary (CC14 and CC36) and two cell line (DLD1 and Ls174T) colon cancer cell types (Fig​(Fig2C).2C). All changes were significative

The strong downregulation of the expression of the intestinal stem cell genesASCL2 andLGR5 (van der Flieret al, 2009; Scheperset al, 2012; Zhuet al, 2012b) by Ivermectin and Selamectin (Fig​(Fig2D)2D) raised the possibility that these drugs could affect WNT-TCF-dependent colon cancer stem cell behavior

Pre-established H358 tumors responded to Ivermectin showing a ˜ 50% repression of growth

Ivermectin hasin vivo efficacy against human colon cancer xenografts sensitive to TCF inhibition with no discernable side effects

Ivermectin (Campbellet al, 1983), an off-patent drug approved for human use, and related macrocyclic lactones, have WNT-TCF pathway response blocking and anti-cancer activities

these drugs block WNT-TCF pathway responses, likely acting at the level of β-CATENIN/TCF function, affecting β-CATENIN phosphorylation status.

anti-WNT-TCF activities of Ivermectin and Selamectin

Ivermectin has a well-known anti-parasitic activity mediated via the deregulation of chloride channels, leading to paralysis and death (Hibbs & Gouaux, 2011; Lynagh & Lynch, 2012). The same mode of action has been suggested to underlie the toxicity of Ivermectin for liquid tumor cells and the potentiation or sensitization effect of Avermectin B1 on classical chemotherapeutics

the specificity of the blockade of WNT-TCF responses we document, at low micromolar doses for Ivermectin and low nanomolar doses for Selamectin, indicate that the blockade of WNT-TCF responses and chloride channel deregulation are distinct modes of action

What is key then is to find a dose and a context where the use of Ivermectin has beneficial effects in patients, paralleling our results with xenografts in mice.

Cell toxicity appears at doses greater (> 10 μM for 12 h or longer or > 5 μM for 48 h or longer for Ivermectin) than those required to block TCF responses and induce apoptosis.

Our data point to a repression of WNT-β-CATENIN/TCF transcriptional responses by Ivermectin, Selamectin and related macrocylic lactones.

(i) The ability of Avermectin B1 to inhibit the activation of WNT-TCF reporter activity by N-terminal mutant (APC-insensitive) β-CATENIN as detected in our screen

(ii) The ability of Avermectin B1, Ivermectin, Doramectin, Moxidectin and Selamectin to parallel the modulation of WNT-TCF targets by dnTCF

(iii) The finding that the specific WNT-TCF response blockade by low doses of Ivermectin and Selamectin is reversed by constitutively active TCF

(iv) The repression of key C-terminal phospho-isoforms of β-CATENIN resulting in the repression of the TCF target and positive cell cycle regulator CYCLIN D1 by Ivermectin and Selamectin

(v) The specific inhibition ofin-vivo-TCF-dependent, but notin-vivo-TCF-independent cancer cells by Ivermectin in xenografts.

These results together with the reduction of the expression of the colon cancer stem cell markersASCL2 andLGR5 (e.g., Hirschet al, 2013; Ziskinet al, 2013) raise the possibility of an inhibitory effect of Ivermectin, Selamectin and related macrocyclic lactones on TCF-dependent cancer stem cells.

the capacity of cancer cells to form 3D spheroids in culture, as well as the growth of these, is also WNT-TCF-dependent (Kanwaret al, 2010) and they were also affected by Ivermectin treatment

If Ivermectin is specific, it should only block TCF-dependent tumor growth. Indeed, the sensitivity and insensitivity of DLD1 and CC14 xenografts to Ivermectin treatment, respectively, together with the desensitization to Ivermectin actionin vivo by constitutively active TCF provide evidence of the specificity of this drug to block an activated WNT-TCF pathway in human cancer.

Ivermectin has a good safety profile since onlyin-vivo-dnTCF-sensitive cancer xenografts are responsive to Ivermectin treatment, and we have not detected side effects in Ivermectin-treated mice at the doses used

previous work has shown that side effects from systemic treatments with clinically relevant doses in humans are rare (Yang, 2012), that birth defects were not observed after exposure of pregnant mothers (Pacquéet al, 1990) and that this drug does not cross the blood–brain barrier (Kokozet al, 1999). Similarly, only dogs with mutantABCB1 (MDR1) alleles leading to a broken blood–brain barrier show Ivermectin neurotoxicity (Mealeyet al, 2001; Orzechowskiet al, 2012)

Indications may include treatment for incurable β-CATENIN/TCF-dependent advanced and metastatic human tumors of the lung, colon, endometrium, and other organs.

Ivermectin, Selamectin, or related macrocyclic lactones could also serve as topical agents for WNT-TCF-dependent skin lesions and tumors such as basal cell carcinomas

they might also be useful as routine prophylactic agents, for instance against nascent TCF-dependent intestinal tumors in patients with familial polyposis and against nascent sporadic colon tumors in the general aging population

HSP70 did not activate NK cells directly. Instead, HSP70 induced the expression of an NKG2D ligand MICA on DCs, which then activated NK cells in an NKG2D-dependent manner.

DCs are the most powerful professional antigen presenting cells (APCs) that are instrumental in processing antigens and orchestrating antigen-specific adaptive immunity and tolerance

NK cells and DCs can functionally interact with each other both in vitro and in vivo

autologous HSP70 could stimulate significant IFN-γ production

The magnitude of the IFN-γ response was different from patient to patient and correlated with the number of functional NK cells

In addition, 10 out of 14 patients had significantly increased IFN-γ producing cells in the peripheral blood after HSP70 vaccinations, which is again in line with increased NK cell activity as reported in our original study in these patients

however, 100 mg/kg of niclosamide could suppress the growth of the relatively slow-growing tumor (CRC039) to the same level

niclosamide was confirmed to inhibit the growth of human CRCs in NOD/SCID mice

niclosamide can inhibit Wnt pathway activation in CRC

The mechanism of action of the niclosamide in our studies is thought to be through internalization of Fzd1 and downregulation of Wnt pathway intermediaries

Recently, Jin et al. (26) reported that niclosamide inhibited the NF-κB pathway and increased reactive oxygen species levels to induce apoptosis in AML cells. In contrast, we did not observe any inhibitory effect of niclosamide on NF-κB signaling in our CRC model

oral administration of niclosamide does result in sufficient distribution of the drug into tumor tissue, to prove a prolonged inhibitory effect on Wnt/ß-catenin signaling, resulting in tumor growth inhibition

we required higher doses (100 ~ 200 mg/kg body weight) of niclosamide in order to demonstrate significant inhibition of tumor growth in NOD/SCID mice

niclosamide concentrations in tumor tissue showed good correlation with those in plasma, suggesting the efficient distribution of niclosamide from blood to tumor tissue

we observed downregulation of Dvl2 and ß-catenin cytosolic expression in niclosamide-treated tumor cells in vivo

One potential concern for the use of niclosamide as an anticancer therapy is the poor absorption of this drug

The Wnt signaling pathway, fundamental to embryonic tissue patterning, is also activated in stem-like cells

The canonical Wnt pathway is activated in approximately 80% of sporadic CRC primarily due to mutations in the APC gene

recent observations reveal that Wnt ligands or inhibitors may affect the growth and survival of colon cancer cells in spite of the presence of APC or CTNNB1 mutations

Hyperthermia differs fundamentally from fever in that it elevates the core body temperature without changing the physiological set point

hyperthermia is induced by increasing the heat load and/or inactivating heat dissipation

mor cells [2]. Although significant cell killing could be achieved by heating cells or tissues to temperatures > 42°C for 1 or more hours, the application, measurement and consistency of this temperature range within the setting of cancer clinical trials

mild temperature hyperthermia (ie, within the fever-range, 39–41°C)

moderate hyperthermia (41°C)

Hsps are a family of stress-induced proteins

they are key regulators of cellular protein activity, turnover and trafficking

Hsps ensure appropriate post-translational protein folding, and are able to refold denatured proteins, or mark irreversibly damaged proteins for destruction

the ability of fever-range hyperthermia to induce reactive immunity against tumor antigens through DCs and NK-cells is likely mediated by Hsps

thermotolerance

Hsps support the malignant phenotype of cancer cells by not only affecting the cells’ survival, but also participating in angiogenesis, invasion, metastasis and immortalization mechanisms

Hsps released from stressed or dying cells activate dendritic cells (DCs), transforming them into mature APCs

In theory, fever-range hyperthermia may take advantage of tumor cell Hsps by inducing their release from tumor cells and augmenting DC priming against tumor antigens

In several models of hyperthermia, heat-treated tumors exhibited improved DC priming and generation of systemic immunity to tumor cell

hyperthermia alone can enhance antigen display by tumor cells, thus rendering them even more susceptible to programmed immune clearance

Fever-range hyperthermia may also induce Hsps

Hsps may exert an adjuvant effect by bolstering MHC class II and co-stimulatory molecule expression by DCs

thermal ablation of liver tumors in particular has demonstrated an ability to potentiate immune responses [57, 58] and elicit robust T-cell infiltrates at ablation sites

specific Hsp, Hsp70, directly inhibits apoptosis pathways in cancer cells, as demonstrated in human pancreatic, prostate and gastric cancer cells

Cross-priming is the ability of extracellular Hsps complexed to tumor peptides to be internalized and presented in the context of MHC class I molecules on APCs, thus allowing potent priming of CTLs against tumor antigens

It has been reported that Hsps are generated from necrotic tumor cell lysates, but not from tumor cells undergoing apoptosis

tumor cells exposed to hyperthermia in the heat shock range (42°C for 4h) prior to lysing, DC activation and cross-priming were significantly enhanced with the application of heat

Due to the ability of Hsps to activate DCs directly by chaperoning tumor antigens upon their release [28], it is possible that both local and regional immune stimulation can be achieved with hyperthermia.

support the use of hyperthermia as an inducer of Hsps to serve as ‘danger signals’, activating antitumor immune responses

whole-body hyperthermia not only augments immune responses, but also stimulates the migration of skin-derived DCs to draining lymph nodes

suggest a valuable role of hyperthermia in DC cancer vaccine strategies

In mice treated with fever-range whole-body hyperthermia, tumor growth was significantly inhibited and NK-cell infiltration increased

exposure to fever-range hyperthermia resulted in improved endogenous NK-cell cytotoxicity to several cancer types

improved activation and function of DCs and NK cells following hyperthermia

Hyperthermia increases the expression ICAM-1 a key adhesion molecule,

The combined effects of hyperthermia on lymphoid tissue endothelium and lymphocytes can promote immune surveillance and increase the probability of naive lymphocytes leaving the circulation and encountering their cognate antigen displayed by DCs in lymphoid organs.

In independent clinical studies, whole-body hyperthermia resulted in a transient decrease in circulating lymphocytes in patients with advanced cancer [12, 94, 99, 100], a finding which mirrored observations in animal models in which lymphocyte entry into lymph noeds was increased following hyperthermia treatment [93]. Enhanced recruitment of lymphocytes to lymphoid tissues may be exploited in the treatment of malignancies.

The initial tumor antigen presentation and initiation of clonal expansion of CTLs transpires in the lymph nodes and cannot take place outside this specialized compartment

the ability of DCs present in the lymph nodes to stimulate an anti-tumor immune response is critical

hyperthermia has been shown to improve immune surveillance by T-cell

and to increase DC trafficking to lymph nodes

the mortality rate of EOC has not been significantly changed for several decades

Sequencing revealed that almost all tumors (96%) had mutations in TP53, which serves as a major driver of this cancer

Low-prevalence but statistically significant mutations in nine other genes including NF1, BRCA1, BRCA2, RB1, and CDK12 were also identified, but the majority of genes were mutated at low frequency, making it difficult to distinguish between driver and passenger mutations

KPNB1 inhibition via any of three KPNB1 siRNAs or importazole treatment induced apoptosis in human EOC cell lines (Fig. 3 A–F and Fig. S4), and was accompanied by an increase in the expression levels of the proapoptotic proteins BAX and cleaved caspase-3

Stable overexpression of KPNB1 in SKOV3 and OVCAR3 (Fig. S6) significantly accelerated cell proliferation/survival (Fig. 5 A–C), confirming that KPNB1 functions as an oncogene in EOC

KPNB1 overexpression significantly decreased caspase-3/7 activity (Fig. 5D), in addition to the expression levels of cleaved caspase-3 and BAX proteins (Fig. 5E). KPNB1 overexpression also decreased p21 and p27 protein levels (Fig. 5E), as opposed to their increase by KPNB1 inhibition

KPNB1 functions as an antiapoptotic and proproliferative oncogene in EOC.

Patients with higher expression levels of KPNB1 showed earlier recurrence and worse prognosis than those with lower expression levels of KPNB1

KPNB1 acts as an oncogene in human EOC and represents a promising therapeutic target.

ivermectin treatment suppressed cell proliferation/viability in a dose-dependent manner (Fig. 7A), indicating that it exerts an antitumor effect on EOC

ivermectin also induced apoptosis

ivermectin increased the expression levels of BAX, and cleaved PARP, as well as p21 and p27

KPNB1 inhibition is responsible for the antitumor effect of ivermectin

we found that ivermectin synergistically reduced cell proliferation/viability in combination with paclitaxel in human EOC cells

Single treatment of ivermectin or paclitaxel reduced tumor growth in nude mice, but, notably, combination treatment of ivermectin and paclitaxel almost completely suppressed tumor growth

ERBB2, is amplified and overexpressed in many cancers, including breast (31), ovary (31), colon (32), bladder (33), non-small-cell lung (34), and gastric cancer (35), and is a poor prognostic factor in certain cancer types

KPNB1 was the second-highest-ranked gene identified in our screen

Increased KPNB1 protein levels have been reported in several cancers, including cervical cancer (42), hepatocellular carcinoma (43), and glioma (44), suggesting KPNB1’s oncogenic potential in these tumor types

our findings suggest that KPNB1 might serve as a master regulator of cell cycle by regulating several cell cycle-related proteins, including p21, p27, and APC/C family members

higher and/or more-frequent doses of ivermectin than currently approved for humans are well tolerated in humans

none of the mice in this study treated with the effective dosage of ivermectin for in vivo anticancer therapy showed severe adverse event

we found that the combination of ivermectin and paclitaxel produces a stronger antitumor effect on EOC cell lines than either drug alone

tumor-associated antigens (TAs)

Proinflammatory cytokines secreted by inflammatory cells can contribute to tumor progression, and soluble factors produced by the tumor in response to nonspecific or tumor-specific signals, such as prostaglandin E2 (PGE2), adenosine, or TGF-β, downregulate functions of immune cells

they are largely ineffective in arresting tumor growth, although they can proliferate and mediate antitumor cytotoxicity on their removal from the tumor bed and ex vivo IL-2 activation.42

DCs (HLA-DR+CD86+CD80+CD14−) are nature’s best APCs

They are a common component of tumor immune infiltrates and are responsible for the uptake, processing, and cross-presentation of TAs to naive or memory T cells, thus playing a crucial role in the generation of tumor-specific effector T cells

DCs control the induction of Treg cells. In patients with cancer, cellular interactions between antigen-presenting DCs and T cells lead to expansion and accumulation of Treg cells at the tumor site and in the periphery

NK cells (CD3−CD56+CD16+), which mediate innate immunity and contain both perforin-rich and granzyme-rich granules, are well equipped to mediate lysis of tumor cells

B cells (CD19+, CD20+) are also rare in most human tumors, with the exception of breast cancer and melanoma

The initial acute inflammation involving the recruitment and influx of antitumor effector cells is replaced by chronic inflammation in later stages of tumor progression

Tissue hypoxia plays a major role in shaping the nature of immune infiltrates in tumors