The anthelmintic flubendazole blocks human melanoma growth and metastasis and suppresses programmed cell death protein-1 and myeloid-derived suppressor cell accumulation

Anticancer role of flubendazole: Effects and molecular mechanisms (Review)

Flubendazole, an anthelmintic agent with a well-established safety profile, has emerged as a promising anticancer drug that has demonstrated efficacy against a spectrum of cancer types over the past decade. Its anticancer properties encompass a multifaceted mechanism of action, including the inhibition of cancer cell proliferation, disruption of microtubule dynamics, regulation of cell cycle, autophagy, apoptosis, suppression of cancer stem cell characteristics, promotion of ferroptosis and inhibition of angiogenesis. The present review aimed to provide a comprehensive overview of the molecular underpinnings of the anticancer activity of flubendazole, highlighting key molecules and regulatory pathways. Given the breadth of the potential of flubendazole, further research is imperative to identify additional cancer types sensitive to flubendazole, refine experimental methodologies for enhancing its reliability, uncover synergistic drug combinations, improve its bioavailability and explore innovative administration methods. The present review provided a foundation for future studies on the role of flubendazole in oncology and described its molecular mechanisms of action.

Targeted modulation of myeloid-derived suppressor cells in the tumor microenvironment: Implications for cancer therapy

Myeloid-derived suppressor cells (MDSCs) represent a heterogeneous population of immature myeloid cells originating from the bone marrow, known for their potent immunosuppressive functions that contribute to tumor immune evasion and progression. This paper provides a comprehensive analysis of the multifaceted interactions between MDSCs and tumors, exploring their distinct phenotypes and immunosuppressive mechanisms. Key roles of MDSCs in tumor biology are discussed, including their involvement in the formation of the pre-metastatic niche, facilitation of angiogenesis, enhancement of vascular permeability, suppression of tumor cell apoptosis, and promotion of resistance to cancer therapies. Additionally, the review highlights recent advances in the development of MDSC-targeting therapies, with a focus on their potential to enhance anti-tumor immunity. The therapeutic potential of Traditional Chinese Medicine (TCM) in modulating MDSC quantity and function is also explored, suggesting a novel approach to cancer treatment by integrating traditional and modern therapeutic strategies.

Reprogramming tumor immune microenvironment by milbemycin oxime results in pancreatic tumor growth suppression and enhanced anti-PD-1 efficacy

Pancreatic ductal adenocarcinoma (PDAC) has a survival rate of 12%, and multiple clinical trials testing anti-PD-1 therapies against PDAC have failed, suggesting a need for a novel therapeutic strategy. In this study, we evaluated the potential of milbemycin oxime (MBO), an antiparasitic compound, as an immunomodulatory agent in PDAC. Our results show that MBO inhibited the growth of multiple PDAC cell lines by inducing apoptosis. In vivo studies showed that the oral administration of 5 mg/kg MBO inhibited PDAC tumor growth in both subcutaneous and orthotopic models by 49% and 56%, respectively. Additionally, MBO treatment significantly increased the survival of tumor-bearing mice by 27 days as compared to the control group. Interestingly, tumors from MBO-treated mice had increased infiltration of CD8+ T cells. Notably, depletion of CD8+ T cells significantly reduced the anti-tumor efficacy of MBO in mice. Furthermore, MBO significantly augmented the efficacy of anti-PD-1 therapy, and the combination treatment resulted in a greater proportion of active cytotoxic T cells within the tumor microenvironment. MBO was safe and well tolerated in all our preclinical toxicological studies. Overall, our study provides a new direction for the use of MBO against PDAC and highlights the potential of repurposing MBO for enhancing anti-PD-1 immunotherapy.

Synergistic intravesical instillation for bladder cancer: CRISPR-Cas13a and fenbendazole combination therapy

BACKGROUND

CRISPR-Cas13a is renowned for its precise and potent RNA editing capabilities in cancer therapy. While various material systems have demonstrated efficacy in supporting CRISPR-Cas13a to execute cellular functions in vitro efficiently and specifically, the development of CRISPR-Cas13a-based therapeutic agents for intravesical instillation in bladder cancer (BCa) remains unexplored.

METHODS

In this study, we introduce a CRISPR-Cas13a nanoplatform, which effectively inhibits PDL1 expression following intravesical instillation. This system utilizes a fusion protein CAST, created through the genetic fusion of CRISPR-Cas13 and the transmembrane peptide TAT. CAST acts as a potent transmembrane RNA editor and is assembled with the transepithelial delivery carrier fluorinated chitosan (FCS). Upon intravesical administration into the bladder, the CAST-crRNAa/FCS nanoparticles (NPs) exhibit remarkable transepithelial capabilities, significantly suppressing PDL1 expression in tumor tissues.To augment immune activation within the tumor microenvironment, we integrated a fenbendazole (FBZ) intravesical system (FBZ@BSA/FCS NPs). This system is formulated through BSA encapsulation followed by FCS coating, positioning FBZ as a powerful chemo-immunological agent.

RESULTS

In an orthotropic BCa model, the FBZ@BSA/FCS NPs demonstrated pronounced tumor cell apoptosis, synergistically reduced PDL1 expression, and restructured the immune microenvironment. This culminated in an enhanced synergistic intravesical instillation approach for BCa. Consequently, our study unveils a novel RNA editor nanoagent formulation and proposes a potential synergistic therapeutic strategy. This approach significantly bolsters therapeutic efficacy, holding promise for the clinical translation of CRISPR-Cas13-based cancer perfusion treatments.

Proteomic analysis of the urothelial cancer landscape

Urothelial bladder cancer (UC) has a wide tumor biological spectrum with challenging prognostic stratification and relevant therapy-associated morbidity. Most molecular classifications relate only indirectly to the therapeutically relevant protein level. We improve the pre-analytics of clinical samples for proteome analyses and characterize a cohort of 434 samples with 242 tumors and 192 paired normal mucosae covering the full range of UC. We evaluate sample-wise tumor specificity and rank biomarkers by target relevance. We identify robust proteomic subtypes with prognostic information independent from histopathological groups. In silico drug prediction suggests efficacy of several compounds hitherto not in clinical use. Both in silico and in vitro data indicate predictive value of the proteomic clusters for these drugs. We underline that proteomics is relevant for personalized oncology and provide abundance and tumor specificity data for a large part of the UC proteome ( www.cancerproteins.org ).

Mechanisms of myeloid-derived suppressor cell-mediated immunosuppression in colorectal cancer and related therapies

Severe immunosuppression is a hallmark of colorectal cancer (CRC). Myeloid-derived suppressor cells (MDSCs), one of the most abundant components of the tumor stroma, play an important role in the invasion, metastasis, and immune escape of CRC. MDSCs create an immunosuppressive microenvironment by inhibiting the proliferation and activation of immunoreactive cells, including T and natural killer cells, as well as by inducing the proliferation of immunosuppressive cells, such as regulatory T cells and tumor-associated macrophages, which, in turn, promote the growth of cancer cells. Thus, MDSCs are key contributors to the emergence of an immunosuppressive microenvironment in CRC and play an important role in the breakdown of antitumor immunity. In this narrative review, we explore the mechanisms through which MDSCs contribute to the immunosuppressive microenvironment, the current therapeutic approaches and technologies targeting MDSCs, and the therapeutic potential of modulating MDSCs in CRC treatment. This study provides ideas and methods to enhance survival rates in patients with CRC.

Targeted therapy, immunotherapy, and small molecules and peptidomimetics as emerging immunoregulatory agents for melanoma

Primary cutaneous melanoma is the most lethal of all skin neoplasms and its incidence is increasing. Clinical management of advanced melanoma in the last decade has been revolutionised by the availability of immunotherapies and targeted therapies, used alone and in combination. This article summarizes advances in the treatment of late-stage melanoma including use of protein kinase inhibitors, antibody-based immune checkpoint inhibitors, adoptive immunotherapy, vaccines and more recently, small molecules and peptidomimetics as emerging immunoregulatory agents.

Flubendazole suppresses VEGF-induced angiogenesis in HUVECs and exerts antitumor effects in PC-3 cells

Flubendazole, an FDA-approved anthelmintic, has been predicted to show strong VEGFR2 inhibitory activity in silico screening combined with in vitro experimental validation, and it has shown anti-cancer effects on some human cancer cell lines, but little is known about the anti-angiogenesis effects and anti-prostate cancer effects. In this study, we analyzed the binding modes and kinetic analysis of flubendazole with VEGFR2 and first demonstrated that flubendazole suppressed VEGF-stimulated cell proliferation, wound-healing migration, cell invasion and tube formation of HUVEC cells, and decreased the phosphorylation of extracellular signal-regulated kinase and serine/threonine kinase Akt, which are the downstream proteins of VEGFR2 that are important for cell growth. What's more, our results showed that flubendazole decreased PC-3 cell viability and proliferation ability, and suppressed PC-3 cell wound healing migration and invasion across a Matrigel-coated Transwell membrane in a concentration-dependent manner. The antiproliferative effects of flubendazole were due to induction of G2-M phase cell cycle arrest in PC-3 cells with decreasing expression of the Cyclin D1 and induction of cell apoptosis with the number of apoptotic cells increased after flubendazole treatment. These results indicated that flubendazole could exert anti-angiogenic and anticancer effects by inhibiting cell cycle and inducing cell apoptosis.

Repurposing approved non-oncology drugs for cancer therapy: a comprehensive review of mechanisms, efficacy, and clinical prospects

Cancer poses a significant global health challenge, with predictions of increasing prevalence in the coming years due to limited prevention, late diagnosis, and inadequate success with current therapies. In addition, the high cost of new anti-cancer drugs creates barriers in meeting the medical needs of cancer patients, especially in developing countries. The lengthy and costly process of developing novel drugs further hinders drug discovery and clinical implementation. Therefore, there has been a growing interest in repurposing approved drugs for other diseases to address the urgent need for effective cancer treatments. The aim of this comprehensive review is to provide an overview of the potential of approved non-oncology drugs as therapeutic options for cancer treatment. These drugs come from various chemotherapeutic classes, including antimalarials, antibiotics, antivirals, anti-inflammatory drugs, and antifungals, and have demonstrated significant antiproliferative, pro-apoptotic, immunomodulatory, and antimetastatic properties. A systematic review of the literature was conducted to identify relevant studies on the repurposing of approved non-oncology drugs for cancer therapy. Various electronic databases, such as PubMed, Scopus, and Google Scholar, were searched using appropriate keywords. Studies focusing on the therapeutic potential, mechanisms of action, efficacy, and clinical prospects of repurposed drugs in cancer treatment were included in the analysis. The review highlights the promising outcomes of repurposing approved non-oncology drugs for cancer therapy. Drugs belonging to different therapeutic classes have demonstrated notable antitumor effects, including inhibiting cell proliferation, promoting apoptosis, modulating the immune response, and suppressing metastasis. These findings suggest the potential of these repurposed drugs as effective therapeutic approaches in cancer treatment. Repurposing approved non-oncology drugs provides a promising strategy for addressing the urgent need for effective and accessible cancer treatments. The diverse classes of repurposed drugs, with their demonstrated antiproliferative, pro-apoptotic, immunomodulatory, and antimetastatic properties, offer new avenues for cancer therapy. Further research and clinical trials are warranted to explore the full potential of these repurposed drugs and optimize their use in treating various cancer types. Repurposing approved drugs can significantly expedite the process of identifying effective treatments and improve patient outcomes in a cost-effective manner.

Immune Checkpoint Inhibitors, Small-Molecule Immunotherapies and the Emerging Role of Neutrophil Extracellular Traps in Therapeutic Strategies for Head and Neck Cancer

Immune checkpoint inhibitor (ICI) therapy has revolutionized the treatment of many cancer types, including head and neck cancers (HNC). When checkpoint and partner proteins bind, these send an "off" signal to T cells, which prevents the immune system from destroying tumor cells. However, in HNC, and indeed many other cancers, more people do not respond and/or suffer from toxic effects than those who do respond. Hence, newer, more effective approaches are needed. The challenge to durable therapy lies in a deeper understanding of the complex interactions between immune cells, tumor cells and the tumor microenvironment. This will help develop therapies that promote lasting tumorlysis by overcoming T-cell exhaustion. Here we explore the strengths and limitations of current ICI therapy in head and neck squamous cell carcinoma (HNSCC). We also review emerging small-molecule immunotherapies and the growing promise of neutrophil extracellular traps in controlling tumor progression and metastasis.

Flubendazole inhibits PD-1 and suppresses melanoma growth in immunocompetent mice

BACKGROUND

Immune checkpoint inhibitor therapy has revolutionized the clinical management of a diverse range of cancer types, including advanced cutaneous melanoma. While immunotherapy targeting the PD-1/PD-L1 system has become standard of care, overall response rates remain unsatisfactory for most patients and there are no approved small molecule inhibitors of the PD-1/PD-L1 system. Flubendazole (FLU) is an anthelmintic that has been used to treat worm infections in humans and animals for decades.

METHODS

Here we tested the anti-cancer activity of systemically delivered FLU with suppression of PD-1 in immunocompetent mice.

RESULTS

In C57BL/6J mice bearing subcutaneous B16F10 melanoma, FLU reduced both tumor growth and PD-1 protein levels without affecting levels of PD-L1. FLU's suppression of PD-1 was accompanied by increased CD3+ T cell infiltration. Western blotting with extracts from human Jurkat T cells showed that FLU inhibited PD-1 protein expression, findings confirmed by flow cytometry. To gain mechanistic insights on FLU's ability to suppress PD-1 protein levels, we performed bulk RNA sequencing on extracts of Jurkat T cells exposed to the benzimidazole for 4 h. From a pool of 14,475 genes there were 1218 differentially-expressed genes; 687 with increased expression and 531 with decreased expression. Among the genes induced by FLU was the AP-1 family member, JUN and surprisingly, pdcd1. KEGG pathway analysis showed FLU up-regulated genes over-represented in multiple pathways (p < 0.01), the top hit being amoebiasis. FLU also affected the expression of genes in cancer-associated pathways, both through down-regulation and up-regulation. Gene set enrichment analysis revealed a large number of immunological signature gene sets correlated with FLU treatment, including gene sets associated with T cell differentiation, proliferation and function. The AP-1 inhibitor T5224 rescued PD-1 protein expression from inhibition by FLU.

CONCLUSION

This study is the first to show that FLU can inhibit melanoma growth with PD-1 suppression in immunocompetent mice.

Anthelmintic Drugs as Emerging Immune Modulators in Cancer

Despite recent advances in treatment approaches, cancer is still one of the leading causes of death worldwide. Restoration of tumor immune surveillance represents a valid strategy to overcome the acquired resistance and cytotoxicity of conventional therapies in oncology and immunotherapeutic drugs, such as immune checkpoint inhibitors and immunogenic cell death inducers, and has substantially progressed the treatment of several malignancies and improved the clinical management of advanced disease. Unfortunately, because of tumor-intrinsic and/or -extrinsic mechanisms for escaping immune surveillance, only a fraction of patients clinically respond to and benefit from cancer immunotherapy. Accumulating evidence derived from studies of drug repositioning, that is, the strategy to identify new uses for approved or investigational drugs that are outside the scope of the original medical indication, has suggested that some anthelmintic drugs, in addition to their antineoplastic effects, exert important immunomodulatory actions on specific subsets of immune cell and related pathways. In this review, we report and discuss current knowledge on the impact of anthelmintic drugs on host immunity and their potential implication in cancer immunotherapy.

Repurposing of Benzimidazole Anthelmintic Drugs as Cancer Therapeutics

Simple Summary

Although non-prescription anthelmintics are often used for cancer treatment, there is a lack of information regarding their anti-cancer effects in clinical settings. The aims of our review are to describe the possibilities and limitations of the anti-cancer effects of benzimidazole anthelmintics and to suggest ways to overcome these limitations. The results of the current review illustrate the potential development of anthelmintics as a useful strategy for cancer treatment based on much preclinical evidence. Furthermore, they suggest that more rigorous studies on whole anti-cancer pathways and development strategies, including formulations, could result in significantly enhanced anti-cancer effects of benzimidazoles as a repurposed cancer therapy in clinical settings.

Abstract

Benzimidazoles have shown significant promise for repurposing as a cancer therapy. The aims of this review are to investigate the possibilities and limitations of the anti-cancer effects of benzimidazole anthelmintics and to suggest ways to overcome these limitations. This review included studies on the anti-cancer effects of 11 benzimidazoles. Largely divided into three parts, i.e., preclinical anti-cancer effects, clinical anti-cancer effects, and pharmacokinetic properties, we examine the characteristics of each benzimidazole and attempt to elucidate its key properties. Although many studies have demonstrated the anti-cancer effects of benzimidazoles, there is limited evidence regarding their effects in clinical settings. This might be because the clinical trials conducted using benzimidazoles failed to restrict their participants with specific criteria including cancer entities, cancer stages, and genetic characteristics of the participants. In addition, these drugs have limitations including low bioavailability, which results in insufficient plasma concentration levels. Additional studies on whole anti-cancer pathways and development strategies, including formulations, could result significant enhancements of the anti-cancer effects of benzimidazoles in clinical situations.

Drug Repurposing to Enhance Antitumor Response to PD-1/PD-L1 Immune Checkpoint Inhibitors

Monoclonal antibodies targeting the PD-1/PD-L1 immune checkpoint have considerably improved the treatment of some cancers, but novel drugs, new combinations, and treatment modalities are needed to reinvigorate immunosurveillance in immune-refractory tumors. An option to elicit antitumor immunity against cancer consists of using approved and marketed drugs known for their capacity to modulate the expression and functioning of the PD-1/PD-L1 checkpoint. Here, we have reviewed several types of drugs known to alter the checkpoint, either directly via the blockade of PD-L1 or indirectly via an action on upstream effectors (such as STAT3) to suppress PD-L1 transcription or to induce its proteasomal degradation. Specifically, the repositioning of the approved drugs liothyronine, azelnidipine (and related dihydropyridine calcium channel blockers), niclosamide, albendazole/flubendazole, and a few other modulators of the PD-1/PD-L1 checkpoint (repaglinide, pimozide, fenofibrate, lonazolac, propranolol) is presented. Their capacity to bind to PD-L1 or to repress its expression and function offer novel perspectives for combination with PD-1 targeted biotherapeutics. These known and affordable drugs could be useful to improve the therapy of cancer.

Flubendazole induces mitochondrial dysfunction and DRP1-mediated mitophagy by targeting EVA1A in breast cancer

Breast cancer is still one of the most common malignancies worldwide and remains a major clinical challenge. We previously reported that the anthelmintic drug flubendazole induced autophagy and apoptosis via upregulation of eva-1 homolog A (EVA1A) in triple-negative breast cancer (TNBC) and was repurposed as a novel anti-tumor agent. However, the detailed underlying mechanisms remain unclear and need further investigation. Here, we found that flubendazole impairs the permeability of the mitochondrial outer membrane and mitochondrial function in breast cancer. Meanwhile, flubendazole increased dynamin-related protein (DRP1) expression, leading to the accumulation of PTEN induced putative kinase 1 (PINK1) and subsequent mitochondrial translocation of Parkin, thereby promoting excessive mitophagy. The resultant excessive mitophagy contributed to mitochondrial damage and dysfunction induced by flubendazole, thus inhibiting breast cancer cells proliferation and migration. Moreover, we demonstrated that excessive DRP1-mediated mitophagy played a critical role in response to the anti-tumor effects of EVA1A in breast cancer. Taken together, our results provide new insights into the molecular mechanisms in relation to the anti-tumor activities of flubendazole, and may be conducive to its rational use in potential clinical applications.

Safety levels of systemic IL-12 induced by cDNA expression as a cancer therapeutic

Aim: The aim of this work is to utilize a gene expression procedure to safely express systemic IL-12 and evaluate its effects in mouse tumor models. Materials & methods: Secondary lymphoid organs and tumors from EL4 and B16 tumor-bearing mice were analyzed by supervised and unsupervised methods. Results: IL-12 cDNA induced systemic IL-12 protein levels lower than the tolerated dose in patients. Control of tumor growth was observed in subcutaneous B16 and EL4 tumors. Systemic IL-12 expression induced a higher frequency of both total tumor-infiltrated CD45+ cells and proliferative IFN-γ+CD8+ T cells along with a lower frequency of CD4+FOXP3+ and CD11b+Gr-1+ cells. Conclusion: This approach characterizes the systemic effects of IL-12, helping to improve treatment of metastases or solid tumors.

Hot-melt extrudability of amorphous solid dispersions of flubendazole-copovidone: An exploratory study of the effect of drug loading and the balance of adjuvants on extrudability and dissolution

The FDA-approved anthelmintic flubendazole has shown potential to be repositioned to treat cancer and dry macular degeneration; however, its poor water solubility limits its use. Amorphous solid dispersions may overcome this challenge, but the balance of excipients may impact the preparation method and drug release. The purpose of this study was to evaluate the influence of adjuvants and drug loading on the development of an amorphous solid dispersion of flubendazole-copovidone by hot-melt extrusion. The drug, copovidone, and adjuvants (magnesium stearate and hydroxypropyl cellulose) mixtures were statistically designed, and the process was performed in a twin-screw extruder. The study showed that flubendazole and copovidone mixtures were highly extrudable, except when drug loading was high (>40%). Furthermore, magnesium stearate positively impacted the extrusion and was more effective than hydroxypropyl cellulose. The extruded materials were evaluated by modulated differential scanning calorimetry and X-ray powder diffraction, obtaining positive amorphization and physical stability results. Pair distribution function analysis indicated the presence of drug-rich domains with medium-range order structure and no evidence of polymer-drug interaction. All extrudates presented faster dissolution (HCl, pH 1.2) than pure flubendazole, and both adjuvants had a notable influence on the dissolution rate. In conclusion, hot-melt extrusion may be a viable option to obtain stable flubendazole:copovidone amorphous dispersions.

Flubendazole Plays an Important Anti-Tumor Role in Different Types of Cancers

Flubendazole, belonging to benzimidazole, is a broad-spectrum insect repellent and has been repurposed as a promising anticancer drug. In recent years, many studies have shown that flubendazole plays an anti-tumor role in different types of cancers, including breast cancer, melanoma, prostate cancer, colorectal cancer, and lung cancer. Although the anti-tumor mechanism of flubendazole has been studied, it has not been fully understood. In this review, we summarized the recent studies regarding the anti-tumor effects of flubendazole in different types of cancers and analyzed the related mechanisms, in order to provide the theoretical reference for further studies in the future.

Emerging insights on functions of the anthelmintic flubendazole as a repurposed anticancer agent

While flubendazole has been used as a macrofilaricide in humans and animals for some 40 years, work in vitro and in preclinical models over the last decade has suggested its potential use as an anticancer agent. This article reviews recent studies in a range of tumor types indicating novel functions for flubendazole in its control of processes associated with tumor growth, spread and renewal including ferroptosis, autophagy, cancer stem-like cell killing and suppression of intratumoral myeloid-derived suppressor cell accumulation and programmed cell death protein 1. Flubendazole's potential use in clinical oncology will require further understanding of its mechanistic roles, range of inhibition of cancer types, capacity for adjunctive therapy and possible reformulation for enhanced solubility, bioavailability and potency.

Drug Repurposing in Oncology: Current Evidence and Future Direction

BACKGROUND

Drug repurposing, the application of known drugs and compounds with a primary non-oncology purpose, might be an attractive strategy to offer more effective treatment options to cancer patients at a low cost and reduced time.

METHODS

This review described a total of 10 kinds of non-oncological drugs from more than 100 mechanical studies as well as evidence from population-based studies. The future direction of repurposed drug screening is discussed by using patient-derived tumor organoids.

RESULTS

Many old drugs showed previously unknown effects or off-target effects and can be intelligently applied for cancer chemoprevention and therapy. The identification of repurposed drugs needs to combine evidence from mechanical studies and population-based studies. Due to the heterogeneity of cancer, patient-derived tumor organoids can be used to screen the non-oncological drugs in vitro.

CONCLUSION

These identified old drugs could be repurposed in oncology and might be added as adjuvants and finally benefit patients with cancers.

Repositioning of Antiparasitic Drugs for Tumor Treatment

Drug repositioning is a strategy for identifying new antitumor drugs; this strategy allows existing and approved clinical drugs to be innovatively repurposed to treat tumors. Based on the similarities between parasitic diseases and cancer, recent studies aimed to investigate the efficacy of existing antiparasitic drugs in cancer. In this review, we selected two antihelminthic drugs (macrolides and benzimidazoles) and two antiprotozoal drugs (artemisinin and its derivatives, and quinolines) and summarized the research progresses made to date on the role of these drugs in cancer. Overall, these drugs regulate tumor growth via multiple targets, pathways, and modes of action. These antiparasitic drugs are good candidates for comprehensive, in-depth analyses of tumor occurrence and development. In-depth studies may improve the current tumor diagnoses and treatment regimens. However, for clinical application, current investigations are still insufficient, warranting more comprehensive analyses.

Survival and Pulmonary Injury After Neonatal Sepsis: PD1/PDL1's Contributions to Mouse and Human Immunopathology

Morbidity and mortality associated with neonatal sepsis remains a healthcare crisis. PD1-/- neonatal mice endured experimental sepsis, in the form of cecal slurry (CS), and showed improved rates of survival compared to wildtype (WT) counterparts. End-organ injury, particularly of the lung, contributes to the devastation set forth by neonatal sepsis. PDL1-/- neonatal mice, in contrast to PD1-/- neonatal mice did not have a significant improvement in survival after CS. Because of this, we focused subsequent studies on the impact of PD1 gene deficiency on lung injury. Here, we observed that at 24 h post-CS (but not at 4 or 12 h) there was a marked increase in pulmonary edema (PE), neutrophil influx, myeloperoxidase (MPO) levels, and cytokine expression sham (Sh) WT mice. Regarding pulmonary endothelial cell (EC) adhesion molecule expression, we observed that Zona occludens-1 (ZO-1) within the cell shifted from a membranous location to a peri-nuclear location after CS in WT murine cultured ECs at 24hrs, but remained membranous among PD1-/- lungs. To expand the scope of this inquiry, we investigated human neonatal lung tissue. We observed that the lungs of human newborns exposed to intrauterine infection had significantly higher numbers of PD1+ cells compared to specimens who died from non-infectious causes. Together, these data suggest that PD1/PDL1, a pathway typically thought to govern adaptive immune processes in adult animals, can modulate the largely innate neonatal pulmonary immune response to experimental septic insult. The potential future significance of this area of study includes that PD1/PDL1 checkpoint proteins may be viable therapeutic targets in the septic neonate.

[Flubendazole Inhibits the Proliferation of A549 and H460 Cells and Promotes Autophagy]

背景与目的

氟苯达唑是一种苯并咪唑类驱虫药, 既往研究发现其对结肠癌、乳腺癌细胞增殖具有抑制作用。本研究旨在探讨氟苯达唑对非小细胞肺癌A549、H460细胞增殖的影响及机制。

方法

通过CCK-8(Cell Counting Kit-8)法检测不同浓度的氟苯达唑对A549、H460细胞活力的影响; Western blot法检测氟苯达唑处理后细胞自噬相关蛋白p62、LC3的表达水平; 自噬双标腺病毒(mRFP-GFP-LC3)转染细胞, 分析细胞内自噬流变化。

结果

氟苯达唑抑制A549、H460细胞增殖, 并呈剂量依赖关系(P < 0.001)。2 μmol/L氟苯达唑处理A549、H460细胞24 h、48 h后p62减少, LC3 II/I比值升高(P < 0.005)。mRFP-GFP-LC3转染细胞显示氟苯达唑处理组红色荧光增加, 提示自噬流增强。

结论

氟苯达唑可以抑制A549、H460细胞增殖并促进自噬。

Repurposing of Drug Candidates for Treatment of Skin Cancer

Skin cancers are highly prevalent malignancies that affect millions of people worldwide. These include melanomas and nonmelanoma skin cancers. Melanomas are among the most dangerous cancers, while nonmelanoma skin cancers generally exhibit a more benign clinical pattern; however, they may sometimes be aggressive and metastatic. Melanomas typically appear in body regions exposed to the sun, although they may also appear in areas that do not usually get sun exposure. Thus, their development is multifactorial, comprising endogenous and exogenous risk factors. The management of skin cancer depends on the type; it is usually based on surgery, chemotherapy, immunotherapy, and targeted therapy. In this respect, oncological treatments have demonstrated some progress in the last years; however, current therapies still present various disadvantages such as little cell specificity, recurrent relapses, high toxicity, and increased costs. Furthermore, the pursuit of novel medications is expensive, and the authorization for their clinical utilization may take 10-15 years. Thus, repositioning of drugs previously approved and utilized for other diseases has emerged as an excellent alternative. In this mini-review, we aimed to provide an updated overview of drugs' repurposing to treat skin cancer and discuss future perspectives.

Antitumor effects of targeting myeloid-derived suppressive cells

Myeloid-derived suppressor cells (MDSCs) are a heterogeneous population of immature myeloid cells with major regulatory functions, which are expanded in pathological conditions, including cancers, infections and autoimmune diseases. Evidence has identified MDSCs as critical cells driving immune suppression in tumor microenvironments. Treatments targeting MDSCs have shown promising results in preclinical studies and some clinical trials. In this review, we discuss therapeutic approaches targeting MDSCs, which may benefit future study.

The Antitumor Potentials of Benzimidazole Anthelmintics as Repurposing Drugs

The development of refractory tumor cells limits therapeutic efficacy in cancer by activating mechanisms that promote cellular proliferation, migration, invasion, metastasis, and survival. Benzimidazole anthelmintics have broad-spectrum action to remove parasites both in human and veterinary medicine. In addition to being antiparasitic agents, benzimidazole anthelmintics are known to exert anticancer activities, such as the disruption of microtubule polymerization, the induction of apoptosis, cell cycle (G2/M) arrest, anti-angiogenesis, and blockage of glucose transport. These antitumorigenic effects even extend to cancer cells resistant to approved therapies and when in combination with conventional therapeutics, enhance anticancer efficacy and hold promise as adjuvants. Above all, these anthelmintics may offer a broad, safe spectrum to treat cancer, as demonstrated by their long history of use as antiparasitic agents. The present review summarizes central literature regarding the anticancer effects of benzimidazole anthelmintics, including albendazole, parbendazole, fenbendazole, mebendazole, oxibendazole, oxfendazole, ricobendazole, and flubendazole in cancer cell lines, animal tumor models, and clinical trials. This review provides valuable information on how to improve the quality of life in patients with cancers by increasing the treatment options and decreasing side effects from conventional therapy.

Flubendazole elicits anti-cancer effects via targeting EVA1A-modulated autophagy and apoptosis in Triple-negative Breast Cancer

Background: Triple-negative breast cancer (TNBC) is one of the most prevalent neoplastic diseases worldwide, but efficacious treatments for this pathological condition are still challenging. The lack of an effective targeted therapy also leads to a poor prognosis for patients affected by TNBC. In the present study, we repurposed the distinctive inhibitory effects of flubendazole, a traditional anthelmintic drug, towards the putative modulation of proliferation and migration of TNBC in vitro and in vivo.

Methods: According to a series of experimental approaches, including immunofluorescence (IF), immunoblotting (IB), siRNA and GFP-mRFP-LC3 plasmid transfection, respectively, we have found that flubendazole is capable of inducing autophagic cell death and apoptosis, thus exerting some anti-proliferative and anti-migration activity in TNBC cells. The therapeutic effects of flubendazole were evaluated by xenograft mouse models, followed by immunohistochemistry (IHC), IF and IB. Changes in the gene expression profiles of flubendazole-treated TNBC cells were analyzed by RNA sequencing (RNA-seq) and validated by IB. The potential binding mode of flubendazole and EVA1A was predicted by molecular docking and demonstrated by site-directed mutagenesis.

Results: We have presently found that flubendazole exhibits a considerable anti-proliferative activity in vitro and in vivo. Mechanistically, the induction of autophagic cell death appears to be pivotal for flubendazole-mediated growth inhibition of TNBC cells, whereas blocking autophagy was able to improve the survival rate and migration ability of flubendazole-treated TNBC cells. Specifically, RNA-seq analysis showed that flubendazole treatment could promote the up-regulation of EVA1A. Flubendazole may regulate autophagy and apoptosis by targeting EVA1A, thus affecting the mechanisms of TNBC proliferation and migration. Furthermore, Thr113 may be the key amino acid residues for the binding of flubendazole to EVA1A.

Conclusion: Our results provide novel insights towards the putative anti-cancer efficacy of flubendazole. Furthermore, here we show that flubendazole could serve as a potential therapeutic drug in TNBC. Altogether, this study highlights the possibility of this repurposed autophagic inducer for future cancer treatments.

Myeloid derived suppressor cells contribute to the malignant progression of oral squamous cell carcinoma

Purpose

The tumor-related myeloid derived suppressor cells (MDSCs), important immunosuppressive cells in tumor microenvironment, play an important role in the cancer progression. This study is aimed to investigate the crosstalk between MDSCs and oral squamous cell carcinoma (OSCC) cells and their role in the malignant progression of OSCC.

Methods

Immunochemistry (IHC) was used to investigate the expression of CD33 in 200 OSCC, 36 premalignant. CD33⁺ MDSCs were sorted and enriched via magnetic-activated cell sorting (MACS) from OSCC patients or health donor, and their phenotypes were identified by flow cytometry. With a co-culture system of MDSCs and OSCC, the effects of MDSCs on OSCC proliferation, apoptosis, migration invasion, epithelial-mesenchymal transition (EMT), and vasculogenic mimicry formation (VM) formation were assessed, respectively. Besides, peripheral blood mononuclear cells (PBMCs) from health donor were cultured with OSCC supernatant, the level of MDSCs and expressions of Arginase (Arg-1) and inducible nitric oxide synthase (iNOS) were measured.

Results

The number of MDSCs was increased in tumor tissues of OSCC patients, and was positively related to the T stage, pathological grade, lymph node metastasis and poor prognosis. Tumor-related MDSCs of the co-culture system promoted OSCC progression by contributing to cell proliferation, migration and invasion as well as inducing EMT and VM. In turn, OSCC cells had potential to induce MDSCs differentiation from PBMCs and increase the expression of Arg-1 and iNOS.

Conclusion

These indicated that the crosstalk between MDSCs and tumor cells facilitated the malignant progression of OSCC cells and the immune suppressive properties of MDSCs, which may provide new insights into tumor treatment on targeting tumor-associated immunosuppressive cells.

Repurposing Drugs for Skin Cancer

Drug repurposing is the process of developing existing or abandoned drugs for a different disease. Repurposing can circumvent higher costs and times associated with conventional drug discovery strategies because toxicity and pharmacokinetics profiles are typically already established. This brief review focuses on efforts to repurpose drugs for skin cancer and includes reuse of antihypertensives, anthelmintics and antifungals among a range of other medicines. Repurposing not only ushers promising known drugs for new indications, the process of repurposing can uncover new mechanistic insights in the pathogenesis of disease and uncover new opportunities for pharmaceutical intervention.