Mebendazole-induced M1 polarisation of THP-1 macrophages may involve DYRK1B inhibition

DYRK1B blockade promotes tumoricidal macrophage activity in pancreatic cancer

OBJECTIVE

Highly malignant pancreatic ductal adenocarcinoma (PDAC) is characterised by an abundant immunosuppressive and fibrotic tumour microenvironment (TME). Future therapeutic attempts will therefore demand the targeting of tumours and stromal compartments in order to be effective. Here we investigate whether dual specificity and tyrosine phosphorylation-regulated kinase 1B (DYRK1B) fulfil these criteria and represent a promising anticancer target in PDAC.

DESIGN

We used transplantation and autochthonous mouse models of PDAC with either genetic Dyrk1b loss or pharmacological DYRK1B inhibition, respectively. Mechanistic interactions between tumour cells and macrophages were studied in direct or indirect co-culture experiments. Histological analyses used tissue microarrays from patients with PDAC. Additional methodological approaches included bulk mRNA sequencing (transcriptomics) and proteomics (secretomics).

RESULTS

We found that DYRK1B is mainly expressed by pancreatic epithelial cancer cells and modulates the influx and activity of TME-associated macrophages through effects on the cancer cells themselves as well as through the tumour secretome. Mechanistically, genetic ablation or pharmacological inhibition of DYRK1B strongly attracts tumoricidal macrophages and, in addition, downregulates the phagocytosis checkpoint and 'don't eat me' signal CD24 on cancer cells, resulting in enhanced tumour cell phagocytosis. Consequently, tumour cells lacking DYRK1B hardly expand in transplantation experiments, despite their rapid growth in culture. Furthermore, combining a small-molecule DYRK1B-directed therapy with mammalian target of rapamycin inhibition and conventional chemotherapy stalls the growth of established tumours and results in a significant extension of life span in a highly aggressive autochthonous model of PDAC.

CONCLUSION

In light of DYRK inhibitors currently entering clinical phase testing, our data thus provide a novel and clinically translatable approach targeting both the cancer cell compartment and its microenvironment.

Novel Compound MMV1804559 from the Global Health Priority Box Exhibits In Vitro and In Vivo Activity against Madurella mycetomatis

OBJECTIVES

Eumycetoma is a neglected tropical disease (NTD) characterized by subcutaneous lesions and the formation of grains. Attempts to treat eumycetoma involve a combination of antifungal treatment and surgery, although the outcome is frequently disappointing. Therefore, there is a need to identify novel antifungal drugs to treat eumycetoma. In this respect, Medicines for Malaria Venture (MMV) has assembled libraries of compounds for researchers to use in drug discovery research against NTD. Therefore, we screened two MMVOpen compound libraries to identify novel leads for eumycetoma.

METHODS

A total of 400 compounds from the COVID Box and the Global Health Priority Box were screened in vitro at 100 µM and 25 µM against the most common causative agents of eumycetoma, namely Madurella mycetomatis and Falciformispora senegalensis, and the resulting IC50 and MIC50 values were obtained. Compounds with an IC50 < 8 µM were identified for possible in vivo efficacy studies using an M. mycetomatis grain model in Galleria mellonella larvae.

RESULTS

Out of the 400 compounds, 22 were able to inhibit both M. mycetomatis and F. senegalensis growth at 100 µM and 25 µM, with compounds MMV1593278, MMV020335, and MMV1804559 being selected for in vivo testing. Of these three, only the pyrazolopyrimidine derivative MMV1804559 was able to prolong the survival of M. mycetomatis-infected G. mellonella larvae. Furthermore, the grains in MMV1804559-treated larvae were significantly smaller compared to the PBS-treated group.

CONCLUSION

MMV1804559 shows promising in vitro and in vivo activity against M. mycetomatis.

Mirk/Dyrk1B Kinase Inhibitors in Targeted Cancer Therapy

During the last years, there has been an increased effort in the discovery of selective and potent kinase inhibitors for targeted cancer therapy. Kinase inhibitors exhibit less toxicity compared to conventional chemotherapy, and several have entered the market. Mirk/Dyrk1B kinase is a promising pharmacological target in cancer since it is overexpressed in many tumors, and its overexpression is correlated with patients' poor prognosis. Mirk/Dyrk1B acts as a negative cell cycle regulator, maintaining the survival of quiescent cancer cells and conferring their resistance to chemotherapies. Many studies have demonstrated the valuable therapeutic effect of Mirk/Dyrk1B inhibitors in cancer cell lines, mouse xenografts, and patient-derived 3D-organoids, providing a perspective for entering clinical trials. Since the majority of Mirk/Dyrk1B inhibitors target the highly conserved ATP-binding site, they exhibit off-target effects with other kinases, especially with the highly similar Dyrk1A. In this review, apart from summarizing the data establishing Dyrk1B as a therapeutic target in cancer, we highlight the most potent Mirk/Dyrk1B inhibitors recently reported. We also discuss the limitations and perspectives for the structure-based design of Mirk/Dyrk1B potent and highly selective inhibitors based on the accumulated structural data of Dyrk1A and the recent crystal structure of Dyrk1B with AZ191 inhibitor.

In vitro and in vivo anticancer activity of mebendazole in colon cancer: a promising drug repositioning

Colon cancer is one of the most common cancers and one of the main causes of death worldwide. Therefore, new treatment methods with better efficiency and fewer risks are very necessary. Mebendazole (MBZ), a drug commonly used for helminthic infections, has recently received attention as a suitable candidate for the treatment of various cancers. This study aimed to investigate, in vitro and in vivo, anticancer activity and selectivity Index of MBZ on colon cancer. HT-29 (human colorectal adenocarcinoma) and MCF-10 (non-tumorigenic epithelial) cell lines were treated with MBZ and Doxorubicin (DOX; positive control drug). IC50 values were estimated using methyl thiazole diphenyl-tetrazolium bromide (MTT) assay. We employed flow cytometry using annexin V-FITC and propidium iodide dyes. For the animal study, colon cancer was subcutaneously induced by CT26 cells (mouse colon cancer) in Bulb/C mice. The mice were treated with 0.05 of LD50, intraperitoneal, every other day for 35 days. Finally, the survival rate, tumor volume, and tumor weight were calculated. Our results demonstrated that IC50 values after 72 h for HT29 and MCF-10 cell lines were 0.29 ± 0.04 µM and 0.80 ± 0.02 µM, respectively. MBZ was more selective than DOX in inhibiting the proliferation of cancer cells compared to normal cells (2. 75 vs. 2.45). Annexin V/PI staining demonstrated that MBZ treatment at IC50 concentrations induced (78 ± 12%) apoptosis in the HT29 cancer cell line after 48 h (P ≤ 0.0001). Also, in mice bearing colon cancer, MBZ significantly reduced the tumor volume (1177 ± 1109 mm3; P ≤ 0.001) and tumor weight (2.30 ± 1.97 g; P ≤ 0.0001) compared to the negative control group (weight 12.45 ± 2.0 g; volume 7346 ± 1077). Also, MBZ increases mean survival time (MST) and increase life span (ILS) percentage in the animal study (51.2 ± 37% vs 93%, respectively). This study suggests that mebendazole strongly and selectively inhibits proliferation and induces apoptosis in colon cancer cells. It may be, accordingly, a promising drug for clinical research and application.

Phase II, Double-Blinded, Randomized, Placebo-Controlled Clinical Trial Investigating the Efficacy of Mebendazole in the Management of Symptomatic COVID-19 Patients

The outbreak of the COVID-19 pandemic has spread throughout the world, affecting almost all nations and territories. The current double-blind, randomized, placebo-controlled, phase II clinical trial sought to evaluate the clinical efficacy and safety of mebendazole as an adjuvant therapy for outpatients with COVID-19. The patients were recruited and divided into two groups: a Mebendazole-treated group and placebo group. The mebendazole and placebo groups were matched for age, sex, and complete blood count (CBC) with differential and liver and kidney function tests at baseline. On the third day, the C-reactive protein (CRP) levels were lower (2.03 ± 1.45 vs. 5.45 ± 3.95, p < 0.001) and the cycle threshold (CT) levels were higher (27.21 ± 3.81 vs. 24.40 ± 3.09, p = 0.046) significantly in the mebendazole group than in the placebo group on the third day. Furthermore, CRP decreased and CT dramatically increased on day three compared to the baseline day in the mebendazole group (p < 0.001 and p = 0.008, respectively). There was a significant inverse correlation between lymphocytes and CT levels in the mebendazole group (r = -0.491, p = 0.039) but not in the placebo group (r = 0.051, p = 0.888). Mebendazole therapy increased innate immunity and returned inflammation to normal levels in COVID-19 outpatients faster than it did in the placebo group in this clinical trial. Our findings add to the growing body of research on the clinical and microbiological benefits of repurposing antiparasitic therapy, specifically mebendazole, for SARS-CoV-2 infection and other viral infections.

The Novel IGF-1R Inhibitor PB-020 Acts Synergistically with Anti-PD-1 and Mebendazole against Colorectal Cancer

CRC is one of the leading causes of cancer mortality worldwide. Chemotherapy is widely used for the treatment of CRC, but its efficacy remains unsatisfactory, mainly due to drug resistance. Therefore, it is urgent to develop new strategies to overcome drug resistance. Combination therapy that aims to achieve additive or synergistic therapeutic effects is an effective approach to tackle the development of drug resistance. Given its established roles in tumor development, progression and metastasis, IGF-1R is a promising drug target for combination therapy against CRC. In this study, we revealed that the novel IGF-1R inhibitor PB-020 can act synergistically with mebendazole (MBZ) to reduce the viability of CRC cells and block xenograft CRC progression. Moreover, the PB-020/anti-PD-1 combination synergistically blocked CRC propagation in the MC38 murine colon carcinoma model. Both combination therapies potently suppressed the PI3K/AKT signaling pathway genes in CRC that may be associated with the development of drug resistance. Our findings establish a preclinical proof-of-concept for combating CRC using combined multi-target treatment with PB-020 and clinical anticancer drugs, which may provide useful clues for clinical trials to evaluate the efficacy and safety of these drug combinations in CRC patients.

Macrophage phenotype-switching in cancer

Tumour-associated macrophages (TAMs) have been found to be of great importance in tumorigenesis and in promoting malignant progression, including tumour angiogenesis and metastasis. Moreover, the TAM phenotype is more likely to be an M2 type. Transforming TAMs by M2-polarization into the tumour-suppressive M1-phenotype is an important approach for tumour therapy. In this review, we analysed the effects of the tumour microenvironment on macrophage phenotype-switching, including hypoxia and cytokines, and the mechanisms of drugs targeting TAMs. Furthermore, we analysed the effects of exosomes on macrophage polarization, phenotype switching of macrophages, and the mechanisms of lipid mediators targeting TAMs.

HPMA Copolymer Mebendazole Conjugate Allows Systemic Administration and Possesses Antitumour Activity In Vivo

Mebendazole and other benzimidazole antihelmintics, such as albendazole, fenbendazole, or flubendazole, have been shown to possess antitumour activity, primarily due to their microtubule-disrupting activity. However, the extremely poor water-solubility of mebendazole and other benzimidazoles, resulting in very low bioavailability, is a serious drawback of this class of drugs. Thus, the investigation of their antitumour potential has been limited so far to administering repeated high doses given peroral (p.o.) or to using formulations, such as liposomes. Herein, we report a fully biocompatible, water-soluble, HPMA copolymer-based conjugate bearing mebendazole (P-MBZ; M_w 28–33 kDa) covalently attached through a biodegradable bond, enabling systemic administration. Such an approach not only dramatically improves mebendazole solubility but also significantly prolongs the half-life and ensures tumour accumulation via an enhanced permeation and retention (EPR) effect in vivo. This P-MBZ has remarkable cytostatic and cytotoxic activities in EL-4 T-cell lymphoma, LL2 lung carcinoma, and CT-26 colon carcinoma mouse cell lines in vitro, with corresponding IC₅₀ values of 1.07, 1.51, and 0.814 µM, respectively. P-MBZ also demonstrated considerable antitumour activity in EL-4 tumour-bearing mice when administered intraperitoneal (i.p.), either as a single dose or using 3 intermittent doses. The combination of P-MBZ with immunotherapy based on complexes of IL-2 and anti-IL-2 mAb S4B6, potently stimulating activated and memory CD8⁺ T cells, as well as NK cells, further improved the therapeutic effect.

HPMA-Based Polymer Conjugates for Repurposed Drug Mebendazole and Other Imidazole-Based Therapeutics

Recently, the antitumor potential of benzimidazole anthelmintics, such as mebendazole and its analogues, have been reported to have minimal side effects, in addition to their well-known anti-parasitic abilities. However, their administration is strongly limited owing to their extremely poor solubility, which highly depletes their overall bioavailability. This study describes the design, synthesis, and physico-chemical properties of polymer-mebendazole nanomedicines for drug repurposing in cancer therapy. The conjugation of mebendazole to water-soluble and biocompatible polymer carrier was carried out via biodegradable bond, relying on the hydrolytic action of lysosomal hydrolases for mebendazole release inside the tumor cells. Five low-molecular-weight mebendazole derivatives, differing in their inner structure, and two polymer conjugates differing in their linker structure, were synthesized. The overall synthetic strategy was designed to enable the modification and polymer conjugation of most benzimidazole-based anthelmintics, such as albendazole, fenbendazole or albendazole, besides the mebendazole. Furthermore, the described methodology may be suitable for conjugation of other biologically active compounds with a heterocyclic N-H group in their molecules.

A phase 2a clinical study on the safety and efficacy of individualized dosed mebendazole in patients with advanced gastrointestinal cancer

Mebendazole is used extensively for treatment of local gut helminthic and invasive echinococcus infections. Anticancer effects of mebendazole have been shown in experimental cancer models and in case studies in patients with advanced cancer. Given these observations, the aims of this study were to investigate safety and efficacy of individualized dosed mebendazole in the cancer indication. Patients with treatment refractory gastrointestinal cancer were treated with individualized dose adjusted mebendazole up to 4 g/day to target a serum concentration of 300 ng/ml. Efficacy and safety were assessed by CT-scans, clinical surveillance and blood sampling. Eleven patients were included in the study and 10 started the treatment phase. Two patients stopped treatment prior to and the remaining eight after tumour evaluation by CT-scan at 8 weeks, all due to progressive disease. Four patients also fulfilled criteria suggested for hyperprogression. Only five patients reached the target serum-mebendazole concentration. No severe adverse effects were observed. Individualized dose adjusted mebendazole is safe and well tolerated in patients with advanced cancer but all patients experienced rapid progressive disease. New approaches such as prodrug development and combination with other anticancer drugs seem needed for further exploration of mebendazole as an anticancer drug.

Mebendazole and temozolomide in patients with newly diagnosed high-grade gliomas: results of a phase 1 clinical trial

Background

Mebendazole is an anthelmintic drug introduced for human use in 1971 that extends survival in preclinical models of glioblastoma and other brain cancers.

Methods

A single-center dose-escalation and safety study of mebendazole in 24 patients with newly diagnosed high-grade gliomas in combination with temozolomide was conducted. Patients received mebendazole in combination with adjuvant temozolomide after completing concurrent radiation plus temozolomide. Dose-escalation levels were 25, 50, 100, and 200 mg/kg/day of oral mebendazole. A total of 15 patients were enrolled at the highest dose studied of 200 mg/kg/day. Trough plasma levels of mebendazole were measured at 4, 8, and 16 weeks.

Results

Twenty-four patients (18 glioblastoma and 6 anaplastic glioma) were enrolled with a median age of 49.8 years. Four patients (at 200 mg/kg) developed elevated grade 3 alanine aminotransferase (ALT) and/or aspartate transaminase (AST) after 1 month, which reversed with lower dosing or discontinuation. Plasma levels of mebendazole were variable but generally increased with dose. Kaplan–Meier analysis showed a 21-month median overall survival with 41.7% of patients alive at 2 years and 25% at 3 and 4 years. Median progression-free survival (PFS) from the date of diagnosis for 17 patients taking more than 1 month of mebendazole was 13.1 months (95% confidence interval [CI]: 8.8–14.6 months) but for 7 patients who received less than 1 month of mebendazole PFS was 9.2 months (95% CI: 5.8–13.0 months).

Conclusion

Mebendazole at doses up to 200 mg/kg demonstrated long-term safety and acceptable toxicity. Further studies are needed to determine mebendazole’s efficacy in patients with malignant glioma.

Mebendazole is unique among tubulin-active drugs in activating the MEK-ERK pathway

We recently showed that the anti-helminthic compound mebendazole (MBZ) has immunomodulating activity in monocyte/macrophage models and induces ERK signalling. In the present study we investigated whether MBZ induced ERK activation is shared by other tubulin binding agents (TBAs) and if it is observable also in other human cell types. Curated gene signatures for a panel of TBAs in the LINCS Connectivity Map (CMap) database showed a unique strong negative correlation of MBZ with MEK/ERK inhibitors indicating ERK activation also in non-haematological cell lines. L1000 gene expression signatures for MBZ treated THP-1 monocytes also connected negatively to MEK inhibitors. MEK/ERK phosphoprotein activity testing of a number of TBAs showed that only MBZ increased the activity in both THP-1 monocytes and PMA differentiated macrophages. Distal effects on ERK phosphorylation of the substrate P90RSK and release of IL1B followed the same pattern. The effect of MBZ on MEK/ERK phosphorylation was inhibited by RAF/MEK/ERK inhibitors in THP-1 models, CD3/IL2 stimulated PBMCs and a MAPK reporter HEK-293 cell line. MBZ was also shown to increase ERK activity in CD4+ T-cells from lupus patients with known defective ERK signalling. Given these mechanistic features MBZ is suggested suitable for treatment of diseases characterized by defective ERK signalling, notably difficult to treat autoimmune diseases.

The Tumor Microenvironment: A Milieu Hindering and Obstructing Antitumor Immune Responses

The success of cancer immunotherapy relies on the knowledge of the tumor microenvironment and the immune evasion mechanisms in which the tumor, stroma, and infiltrating immune cells function in a complex network. The potential barriers that profoundly challenge the overall clinical outcome of promising therapies need to be fully identified and counteracted. Although cancer immunotherapy has increasingly been applied, we are far from understanding how to utilize different strategies in the best way and how to combine therapeutic options to optimize clinical benefit. This review intends to give a contemporary and detailed overview of the different roles of immune cells, exosomes, and molecules acting in the tumor microenvironment and how they relate to immune activation and escape. Further, current and novel immunotherapeutic options will be discussed.

M1-like macrophages are potent producers of anti-viral interferons and M1-associated marker-positive lung macrophages are decreased during rhinovirus-induced asthma exacerbations

BACKGROUND

Macrophages (Mф) can be M1/M2 polarized by Th1/2 signals, respectively. M2-like Mф are thought to be important in asthma pathogenesis, and M1-like in anti-infective immunity, however their roles in virus-induced asthma exacerbations are unknown. Our objectives were (i) to assess polarised Mф phenotype responses to rhinovirus (RV) infection in vitro and (ii) to assess Mф phenotypes in healthy subjects and people with asthma before and during experimental RV infection in vivo.

METHODS

We investigated characteristics of polarized/unpolarized human monocyte-derived Mф (MDM, from 3-6 independent donors) in vitro and evaluated frequencies of M1/M2-like bronchoalveolar lavage (BAL) Mф in experimental RV-induced asthma exacerbation in 7 healthy controls and 17 (at baseline) and 18 (at day 4 post infection) people with asthma.

FINDINGS

We observed in vitro: M1-like but not M2-like or unpolarized MDM are potent producers of type I and III interferons in response to RV infection (P<0.0001), and M1-like are more resistant to RV infection (P<0.05); compared to M1-like, M2-like MDM constitutively produced higher levels of CCL22/MDC (P = 0.007) and CCL17/TARC (P<0.0001); RV-infected M1-like MDM were characterized as CD14+CD80+CD197+ (P = 0.002 vs M2-like, P<0.0001 vs unpolarized MDM). In vivo we found reduced percentages of M1-like CD14+CD80+CD197+ BAL Mф in asthma during experimental RV16 infection compared to baseline (P = 0.024).

INTERPRETATION

Human M1-like BAL Mф are likely important contributors to anti-viral immunity and their numbers are reduced in patients with allergic asthma during RV-induced asthma exacerbations. This mechanism may be one explanation why RV-triggered clinical and pathologic outcomes are more severe in allergic patients than in healthy subjects.

FUNDING

ERC FP7 Advanced grant 233015, MRC Centre Grant G1000758, Asthma UK grant 08-048, NIHR Biomedical Research Centre funding scheme, NIHR BRC Centre grant P26095, the Predicta FP7 Collaborative Project grant 260895, RSF grant 19-15-00272, Megagrant No 14.W03.31.0024.

Mebendazole as a Candidate for Drug Repurposing in Oncology: An Extensive Review of Current Literature

Anticancer treatment efficacy is limited by the development of refractory tumor cells characterized by increased expression and activity of mechanisms promoting survival, proliferation, and metastatic spread. The present review summarizes the current literature regarding the use of the anthelmintic mebendazole (MBZ) as a repurposed drug in oncology with a focus on cells resistant to approved therapies, including so called “cancer stem cells”. Mebendazole meets many of the characteristics desirable for a repurposed drug: good and proven toxicity profile, pharmacokinetics allowing to reach therapeutic concentrations at disease site, ease of administration and low price. Several in vitro studies suggest that MBZ inhibits a wide range of factors involved in tumor progression such as tubulin polymerization, angiogenesis, pro-survival pathways, matrix metalloproteinases, and multi-drug resistance protein transporters. Mebendazole not only exhibits direct cytotoxic activity, but also synergizes with ionizing radiations and different chemotherapeutic agents and stimulates antitumoral immune response. In vivo, MBZ treatment as a single agent or in combination with chemotherapy led to the reduction or complete arrest of tumor growth, marked decrease of metastatic spread, and improvement of survival. Further investigations are warranted to confirm the clinical anti-neoplastic activity of MBZ and its safety in combination with other drugs in a clinical setting.