The antihistamines clemastine and desloratadine inhibit STAT3 and c-Myc activities and induce apoptosis in cutaneous T-cell lymphoma cell lines

Clemastine fumarate attenuates tauopathy and meliorates cognition in hTau mice via autophagy enhancement

Clemastine fumarate, which has been identified as a promising agent for remyelination and autophagy enhancement, has been shown to mitigate Aβ deposition and improve cognitive function in the APP/PS1 mouse model of Alzheimer's disease. Based on these findings, we investigated the effect of clemastine fumarate in hTau mice, a different Alzheimer's disease model characterized by overexpression of human Tau protein. Surprisingly, clemastine fumarate was effective in reducing pathological deposition of Tau protein, protecting neurons and synapses from damage, inhibiting neuroinflammation, and improving cognitive impairment in hTau mice. Interestingly, chloroquine, an autophagy inhibitor, had a significant impact on total and Sarkosyl fractions of autophagy, demonstrating that it can interrupt autophagy. Notably, after administration of chloroquine, levels of Tau protein were significantly increased. When clemastine fumarate was co-administered with chloroquine, the protective effects were reversed, indicating that clemastine fumarate indeed triggered autophagy and promoted the degradation of Tau protein, while also inhibiting further Tauopathy-related neuroinflammation and synapse loss to improve cognitive function in hTau mice.

Proapoptotic and proautophagy effect of H1-receptor antagonist desloratadine in human glioblastoma cell lines

Glioblastomas are aggressive and usually incurable high-grade gliomas without adequate treatment. In this study, we aimed to investigate the potential of desloratadine to induce apoptosis/autophagy as genetically regulated processes that can seal cancer cell fates. All experiments were performed on U251 human glioblastoma cell line and primary human glioblastoma cell culture. Cytotoxic effect of desloratadine was investigated using MTT and CV assays, while oxidative stress, apoptosis, and autophagy were detected by flow cytometry and immunoblot. Desloratadine treatment decreased cell viability of U251 human glioblastoma cell line and primary human glioblastoma cell culture (IC50 value 50 µM) by an increase of intracellular reactive oxygen species and caspase activity. Also, desloratadine decreased the expression of main autophagy repressor mTOR and its upstream activator Akt and increased the expression of AMPK. Desloratadine exerted dual cytotoxic effect inducing both apoptosis- and mTOR/AMPK-dependent cytotoxic autophagy in glioblastoma cells and primary glioblastoma cell culture.

Drug repurposing: Clemastine fumarate and neurodegeneration

Neurodegenerative diseases have been a weighty problem in elder people who might be stricken with motor or/and cognition defects with lower life quality urging for effective treatment. Drugs are costly from development to market, so that drug repurposing, exploration of existing drugs for novel therapeutic purposes, becomes a wise and popular strategy to raise new treatment options. Clemastine fumarate, different from anti-allergic effect as H1 histamine antagonist, was screened and identified as promising drug for remyelination and autophagy enhancement. Surprisingly, fumarate salt also has similar effect. Hence, whether clemastine fumarate would make a protective impact on neurodegenerative diseases and what contribution fumarate probably makes are intriguing to us. In this review, we summarize the potential mechanism surrounding clemastine fumarate in current literature, and try to distinguish independent or synergistic effect between clemastine and fumarate, aiming to find worthwhile research direction for neurodegeneration diseases.

The Multidirectional Effect of Azelastine Hydrochloride on Cervical Cancer Cells

A major cause of cancer cell resistance to chemotherapeutics is the blocking of apoptosis and induction of autophagy in the context of cell adaptation and survival. Therefore, new compounds are being sought, also among drugs that are commonly used in other therapies. Due to the involvement of histamine in the regulation of processes occurring during the development of many types of cancer, antihistamines are now receiving special attention. Our study concerned the identification of new mechanisms of action of azelastine hydrochloride, used in antiallergic treatment. The study was performed on HeLa cells treated with different concentrations of azelastine (15-90 µM). Cell cycle, level of autophagy (LC3 protein activity) and apoptosis (annexin V assay), activity of caspase 3/7, anti-apoptotic protein of Bcl-2 family, ROS concentration, measurement of mitochondrial membrane potential (Δψm), and level of phosphorylated H2A.X in response to DSB were evaluated by cytometric method. Cellular changes were also demonstrated at the level of transmission electron microscopy and optical and fluorescence microscopy. Lysosomal enzyme activities-cathepsin D and L and cell viability (MTT assay) were assessed spectrophotometrically. Results: Azelastine in concentrations of 15-25 µM induced degradation processes, vacuolization, increase in cathepsin D and L activity, and LC3 protein activation. By increasing ROS, it also caused DNA damage and blocked cells in the S phase of the cell cycle. At the concentrations of 45-90 µM, azelastine clearly promoted apoptosis by activation of caspase 3/7 and inactivation of Bcl-2 protein. Fragmentation of cell nucleus was confirmed by DAPI staining. Changes were also found in the endoplasmic reticulum and mitochondria, whose damage was confirmed by staining with rhodamine 123 and in the MTT test. Azelastine decreased the mitotic index and induced mitotic catastrophe. Studies demonstrated the multidirectional effects of azelastine on HeLa cells, including anti-proliferative, cytotoxic, autophagic, and apoptotic properties, which were the predominant mechanism of death. The revealed novel properties of azelastine may be practically used in anti-cancer therapy in the future.

Safety and Danger Considerations of Novel Treatments for Atopic Dermatitis in Context of Primary Cutaneous Lymphomas

The impact of new and emerging therapies on the microenvironment of primary cutaneous lymphomas (PCLs) has been recently raised in the literature. Concomitantly, novel treatments are already used or registered (dupilumab, upadacitinib) and others seem to be added to the armamentarium against atopic dermatitis. Our aim was to review the literature on interleukins 4, 13, 22, and 31, and JAK/STAT pathways in PCLs to elucidate the safety of using biologics (dupilumab, tralokinumab, fezakinumab, nemolizumab) and small molecule inhibitors (upadacitinib, baricitinib, abrocitinib, ruxolitinib, tofacitinib) in the treatment of atopic dermatitis. We summarized the current state of knowledge on this topic based on the search of the PubMed database and related references published before 21 October 2021. Our analysis suggests that some of the mentioned agents (dupilumab, ruxolitinib) and others may have a direct impact on the progression of cutaneous lymphomas. This issue requires further study and meticulous monitoring of patients receiving these drugs to ensure their safety, especially in light of the FDA warning on tofacitinib. In conclusion, in the case of the rapid progression of atopic dermatitis/eczema, especially in patients older than 40 years old, there is a necessity to perform a biopsy followed by a very careful pathological examination.

Pre-activation with TLR7 in combination with thioridazine and loratadine promotes tumoricidal T-cell activity in colorectal cancer

Colorectal cancer (CRC) is the third most common malignancy worldwide. Our previous studies have shown that combinatorial treatment with thioridazine and loratadine may effectively inhibit CRC. However, the translation of these research findings to clinical practice was impaired by issues related to a lack of therapeutic specificity and to immune evasion. Toll-like receptor (TLR) agonists have been used as adjuvants to enhance the effectiveness of cancer vaccines. The aim of this study was to evaluate the therapeutic efficiency of immunotherapy with thioridazine and loratadine in combination with resiqumiod (R848), a small-molecule TLR7 agonist, in suppressing CRC growth in a mouse model. Twenty-four BALB/c mice were randomly assigned to treatment with PBS, R848, thioridazine + loratadine, or thioridazine + loratadine + R848. Cytokine levels were measured with ELISA. Overall survival, as well as tumor volume and tumor weight, was recorded. Cytotoxicity was measured by counting the numbers of CD8 and CD3-positive (CD8CD3) or CD4 and CD3-positive (CD3CD4) T-cells. The immune response induced by cytokines (as interferon-γ, interleukin-6, and tumor necrosis factor-α) was significantly stronger in mice treated with thioridazine + loratadine + R848. Moreover, thioridazine + loratadine + R848 significantly delayed tumor development and prolonged survival, which was associated with enhanced immune response and dendritic cell maturation. This study suggested that thioridazine + loratadine + R848 combinatorial treatment may be effective in overcoming immune evasion by tumor cells, with promising therapeutic potential in CRC.

The Antihistamine Deptropine Induces Hepatoma Cell Death through Blocking Autophagosome-Lysosome Fusion

Some antihistamines have exhibited significant antitumor activity alone or in combination with other therapies in in vitro and clinical studies. However, the underlying mechanisms of how antihistamines inhibit hepatocellular carcinoma proliferation are still unknown. We first screened the antiproliferation activity of 12 benzocycloheptene structural-analogue drugs, and results showed that deptropine was the most potent inhibitor of both Hep3B and HepG2 human hepatoma cells. Deptropine significantly increased light chain 3B-II (LC3B-II) expression but did not induce sequestosome 1 (SQSTM1/p62) degradation in either cell line. Interestingly, other autophagy-related proteins, such as autophagy-related 7 (ATG7), vacuolar protein sorting 34 (VPS34), phosphorylated adenosine 5'-monophosphate-activated protein kinase (AMPK), and phosphorylated protein kinase B (PKB, also known as Akt), exhibited no significant change in either deptropine-treated cell line. Deptropine also inhibited the processing of cathepsin L from its precursor form to its mature form. Immunofluorescence microscopy showed an increase of autophagosomes in deptropine-treated cells, but deptropine blocked the fusion between autophagosomes and lysosomes. In a xenograft nude mice model, 2.5 mg/kg deptropine showed a great inhibitory effect on Hep3B tumor growth. These results suggest that deptropine can induce in vitro and in vivo hepatoma cell death, and the underlying mechanisms might be mediated through inhibiting autophagy by blocking autophagosome-lysosome fusion.

Precision-engineered reporter cell lines reveal ABCG2 regulation in live lung cancer cells

Expression of the ABCG2 multidrug transporter is a marker of cancer stem cells and a predictor of recurrent malignant disease. Understanding how human ABCG2 expression is modulated by pharmacotherapy is crucial in guiding therapeutic recommendations and may aid rational drug development. Genome edited reporter cells are useful in investigating gene regulation and visualizing protein activity in live cells but require precise targeting to preserve native regulatory regions. Here, we describe a fluorescent reporter assay that allows the noninvasive assessment of ABCG2 regulation in human lung adenocarcinoma cells. Using CRISPR-Cas9 gene editing coupled with homology-directed repair, we targeted an EGFP coding sequence to the translational start site of ABCG2, generating ABCG2 knock-out and in situ tagged ABCG2 reporter cells. Using the engineered cell lines, we show that ABCG2 is upregulated by a number of anti-cancer medications, HDAC inhibitors, hypoxia-mimicking agents and glucocorticoids, supporting a model in which ABCG2 is under the control of a general stress response. To our knowledge, this is the first description of a fluorescent reporter assay system designed to follow the endogenous regulation of a human ABC transporter in live cells. The information gained may guide therapy recommendations and aid rational drug design.

The role of H1 antihistamines in contralateral breast cancer: a Danish nationwide cohort study

Background

Preclinical studies have shown both pro- and antineoplastic effects of antihistamines. Here, we evaluated the effect of H1 antihistamines on contralateral breast cancer (CBC) risk, and whether cationic amphiphilic (CAD) antihistamines could increase the sensitivity to chemotherapy.

Methods

From the Danish Breast Cancer Group clinical database, we identified all women aged ≥20 years with a first-time diagnosis of breast cancer during 1996–2012. Information on drug use, CBC and potential confounding factors was retrieved from nationwide registries. Using Cox proportional hazard regression models, we calculated hazard ratios (HRs) and 95% confidence intervals (CIs) for CBC associated with H1-antihistamine use.

Results

We identified 52,723 patients with breast cancer with a total of 310,583 person-years of follow-up. Among them, 1444 patients developed a new primary tumour in the contralateral breast. Post-diagnosis use of H1 antihistamines (≥2 prescriptions) was not strongly associated with CBC risk (HR 1.08, 95% CI: 0.90–1.31) compared with non-use (<2 prescriptions). Use of CAD antihistamines among patients receiving chemotherapy was not associated with a decrease in CBC risk.

Conclusions

Taken together, our findings do not suggest any association of H1-antihistamine use with CBC development.

The role of regulatory T cells and genes involved in their differentiation in pathogenesis of selected inflammatory and neoplastic skin diseases. Part III: Polymorphisms of genes involved in Tregs' activation and function

Regulatory T cells (Tregs) represent a cell type that promotes immune tolerance to autologous components and maintains immune system homeostasis. The abnormal function of Tregs is relevant to the pathogenesis of several skin diseases like psoriasis, atopic dermatitis, systemic lupus erythematosus, cutaneous T-cell lymphomas, and skin cancer and is also important in rheumatoid arthritis, diabetes and other autoimmune diseases. In this review, we will summarize the role of mutations and/or polymorphisms of genes involved in Tregs development, and functions in the pathogenesis of selected skin diseases.

Allergy and risk of hematologic malignancies: associations and mechanisms

Increasing evidence indicates that a dysregulated immune system, as the one found in allergic disorders, can affect survival of tumor cells. A possible association between allergies and risk of hematologic malignancies has been examined in several epidemiological studies; however, results were not always consistent. The aim of this review is to report the preclinical and clinical data, which support a correlation between allergy and hematologic neoplasms. Immune system modulation could represent a powerful tool in the prevention and treatment of hematologic malignancies.

Novel therapies for cutaneous T-cell lymphoma: what does the future hold?

INTRODUCTION

Cutaneous T-cell lymphomas (CTCLs) represent a group of extranodal non-Hodgkin lymphomas, of which mycosis fungoides (MF) is the most frequent. Standard therapeutic approaches are well established and often achieve stable disease. However, cure for MF is rare and thus novel therapies are needed.

AREAS COVERED

This review provides a discussion of the most promising new therapeutic approaches in the management of MF and other rare CTCLs. It includes targeted therapies with antibodies against surface molecules on malignant T cells (e.g., brentuximab), novel chemotherapeutic agents (e.g., pralatrexate), small-molecule compounds (e.g., panobinostat) and evidence of emerging targets in CTCLs (e.g., anti-IL-31). It also provides discussion of immune checkpoint inhibitors such as anti-PD1 that are worth considering in the treatment of leukaemic CTCL variants. Finally, it gives a brief overview of the possible use of stem-cell transplantation.

EXPERT OPINION

There is no doubt that progress has been made in the treatment of CTCLs with new, innovative and promising therapies approaching. However, there is still an urgent need to identify and test additional targets in well-designed clinical trials.