The anti-histaminic cyproheptadine synergizes the antineoplastic activity of bortezomib in mantle cell lymphoma through its effects as a histone deacetylase inhibitor

OPALS: A New Osimertinib Adjunctive Treatment of Lung Adenocarcinoma or Glioblastoma Using Five Repurposed Drugs

Background: Pharmacological targeting aberrant activation of epidermal growth factor receptor tyrosine kinase signaling is an established approach to treating lung adenocarcinoma. Osimertinib is a tyrosine kinase approved and effective in treating lung adenocarcinomas that have one of several common activating mutations in epidermal growth factor receptor. The emergence of resistance to osimertinib after a year or two is the rule. We developed a five-drug adjuvant regimen designed to increase osimertinib’s growth inhibition and thereby delay the development of resistance. Areas of Uncertainty: Although the assembled preclinical data is strong, preclinical data and the following clinical trial results can be discrepant. The safety of OPALS drugs when used individually is excellent. We have no data from humans on their tolerability when used as an ensemble. That there is no data from the individual drugs to suspect problematic interaction does not exclude the possibility. Data Sources: All relevant PubMed.org articles on the OPALS drugs and corresponding pathophysiology of lung adenocarcinoma and glioblastoma were reviewed. Therapeutic Opinion: The five drugs of OPALS are in wide use in general medicine for non-oncology indications. OPALS uses the anti-protozoal drug pyrimethamine, the antihistamine cyproheptadine, the antibiotic azithromycin, the antihistamine loratadine, and the potassium sparing diuretic spironolactone. We show how these inexpensive and generically available drugs intersect with and inhibit lung adenocarcinoma growth drive. We also review data showing that both OPALS adjuvant drugs and osimertinib have data showing they may be active in suppressing glioblastoma growth.

Cyproheptadine, an epigenetic modifier, exhibits anti-tumor activity by reversing the epigenetic silencing of IRF6 in urothelial carcinoma

BACKGROUND

Urothelial carcinoma (UC) is the second most common malignancy of the urinary system with high rate of recurrence, UC patients therefore needed to be treated with surgery followed by chemotherapy. Development of novel therapeutics with minimal side-effect is an urgent issue. Our previous study showed that cyproheptadine (CPH), an anti-histamine, exhibited antitumor activity in UC in vitro and in an xenograft model. However, the molecular mechanism of how CPH inhibits tumor progression is not fully understood.

METHODS

Genes that were upregulated after treatment with CPH in UC cells, were examined by RNA-Seq. Real-time quantitative PCR (RT-qPCR) was employed to detect IRF6 expression while COBRA assay and bisulphite pyrosequencing were used to examine promoter methylation of IRF6. Enrichment of total H3K27 acetylation and H3K4 mono-methylation were detected by western blotting. Colony formation and flow cytometry were used to examine proliferation and apoptosis in UC cells overexpressed or depleted with IRF6. Nude mice xenograft model was used to examine the effect of IRF6 in UC.

RESULTS

Our result showed that several genes, including IRF6 were upregulated after treatment with CPH in BFTC905 UC cells. Further experiments found that treatment of CPH could restore the expression of IRF6 in several other UC cell lines, probably due to promoter hypomethylation and enrichment of H3K27 acetylation and H3K4 mono-methylation. These results may be due to the fact that CPH could alter the activity, but not the expression of epigenetic modifiers. Finally, re-expression of IRF6 in UC inhibited tumor growth in vitro and in an xenograft mouse model, by inducing apoptosis.

CONCLUSION

In conclusion, our results suggested that CPH may be an epigenetic modifier, modulating the expression of the potential tumor suppressor IRF6, in inhibiting tumor growth in UC.

Cyproheptadine causes apoptosis and decreases inflammation by disrupting thiol/disulfide balance and enhancing the levels of SIRT1 in C6 glioblastoma cells

Cyproheptadine is first-generation antihistamine drug, that is, H₁ receptor antagonist, with a drug being anesthetic, anti-serotonergic and anti-cholinergic and started to be used clinically in the 1960s. As firstly utilized as an anti-allergic drug, usage of cyproheptadine was expanded to other cases including serotonin syndrome, appetite increasing, migraines and insomnia. However, there are almost few studies seeking to explore the association between cyproheptadine and cancer in general. In the present study, we sought to determine the impact of cyproheptadine on C6 glioblastoma cells by morphological, biochemical and cytotoxic analyzes. We searched the effective doses of cyproheptadine for C6 glioblastoma cells and examined the cells under an inverted microscope. Next, we determined the protein levels of SIRT1, NFκB and IL-6 protein. Then, we measured and calculated the levels of thiols, disulfide bonds and related parameters. After that, we evaluated apoptotic activity by Annexin V and caspase 3 assays. As a result, we detected a dose-dependent increase in apoptosis and SIRT 1 protein levels, and a decrease in inflammatory proteins. Furthermore, we have detected a drop in thiol and disulfide content. Our study suggests that Cyproheptadine causes apoptosis and decreases inflammation by disrupting thiol/disulfide balance and enhancing the levels of SIRT1, offering the potential for being an anti-cancer drug. Therefore, it might be further investigated in future studies.

N-Substituted piperazine derivatives as potential multitarget agents acting on histamine H3 receptor and cancer resistance proteins

Taking into account that multidrug resistance (MDR) is the main cause for chemotherapeutic failure in cancer treatment, the ability of novel histamine H₃ receptor ligands to reverse the cancer MDR was evaluated, using the ABCB1 efflux pump inhibition assay in mouse MDR T-lymphoma cells. The most active compounds displayed significant cytotoxic and antiproliferative effects as well as a very potent MDR efflux pump inhibitory action, 3-5-fold stronger than that of reference inhibitor verapamil. Although these compounds possess weak antagonistic properties against histamine H₃ receptors, they are valuable pharmacological tools in the search for novel anticancer molecules. Furthermore, for the most active compounds, an insight into mechanisms of action using either, the luminescent Pgp-Glo™ Assay in vitro or docking studies to human Pgp, was performed.

Histamine receptors and cancer pharmacology: an update

In the present review, we will discuss the recent advances in the understanding of the role of histamine and histamine receptors in cancer biology. The controversial role of the histaminergic system in different neoplasias including gastric, colorectal, oesophageal, oral, pancreatic, liver, lung, skin, blood and breast cancers will be reviewed. The expression of histamine receptor subtypes, with special emphasis on the histamine H4 receptor, in different cell lines and human tumours, the signal transduction pathways and the associated biological responses as well as the in vivo treatment of experimental tumours with pharmacological ligands will be described. The presented evidence demonstrates that histamine regulates cancer-associated biological processes during cancer development in multiple cell types, including neoplastic cells and cells in the tumour micro-environment. The outcome will depend on tumour cell type, the level of expression of histamine receptors, signal transduction associated with these receptors, tumour micro-environment and histamine metabolism, reinforcing the complexity of cancer disease. Findings show the pivotal role of H4 receptors in the development and progression of many types of cancers, and considering its immunomodulatory properties, the H4 receptor appears to be the most promising molecular therapeutic target for cancer treatment within the histamine receptor family. Furthermore, the H4 receptor is differentially expressed in tumours compared with normal tissues, and in most cancer types in which data are available, H4 receptor expression is associated with clinicopathological characteristics, suggesting that H4 receptors might represent a novel cancer biomarker. LINKED ARTICLES: This article is part of a themed section on New Uses for 21st Century. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v177.3/issuetoc.

Cyproheptadine exhibits antitumor activity in urothelial carcinoma cells by targeting GSK3β to suppress mTOR and β-catenin signaling pathways

Cyproheptadine, a serotonin antagonist, has recently been reported to function as a novel therapeutic agent by inhibiting PI3K/AKT signaling in several human cancers. However, the therapeutic effect of cyproheptadine in urothelial carcinoma (UC) has never been explored. In this study, we determined the effect of cyproheptadine on the growth of five human UC cell lines and an in vivo xenograft model. The results showed that cyproheptadine exerted an inhibitory effect on the proliferation of UC cells both in vitro and in vivo. Cyproheptadine also induced cell cycle arrest in the G1 phase, subsequently followed by apoptosis and necrosis. The underlying mechanisms of cell cycle arrest were associated with the reduction of c-Myc, induction of p21 and p27, and the stabilization of Rb expression. In addition, the suppression of the GSK3β/TSC2/mTOR pathway and deregulation of the GSK3β/β-catenin signaling were observed in cyproheptadine-treated UC cells. Furthermore, cyproheptadine-induced apoptosis was associated with ANGPTL4 expression followed by activation of caspase3 and PARP in UC cells. Our experimental results provide evidence that cyproheptadine is a suitable therapeutic agent for the treatment of UC.

The novel kinesin spindle protein (KSP) inhibitor SB-743921 exhibits marked activity in in vivo and in vitro models of aggressive large B-cell lymphoma

The kinesin spindle protein (KSP) is a mitotic protein essential for cell cycle control and motility. SB-743921 (hereafter SB-921) is an inhibitor that selectively targets the ATP-binding domain of the KSP. The preclinical activity of SB-921 was evaluated in models of diffuse large B-cell lymphoma (DLBCL). The cytotoxicity of SB-921 was evaluated in a series of germinal center (GC-DLBCL) and post-germinal center (ABC-DLBCL) DLBCL cell lines and a murine lymphoma xenograft model. GC-DLBCL lines generally demonstrated greater sensitivity to SB-921. IC50 values ranged between 1 nM and 900 nM for GC-DLBCL compared to 1 nM to 10 μM for ABC lines. SB-921 demonstrated marked activity in a xenograft model of Ly-1 (GC-DLBCL). While SB-921 was relatively more active in GC derived cell lines, ABC-derived lines still underwent apoptosis at higher concentrations. These results demonstrate that SB-921 inhibits proliferation and induces apoptosis in both GC-DLBCL and ABC-DLBCL.

Cyproheptadine, an antihistaminic drug, inhibits proliferation of hepatocellular carcinoma cells by blocking cell cycle progression through the activation of P38 MAP kinase

Background

Hepatocellular carcinoma (HCC) is a major cause of cancer deaths worldwide. However, current chemotherapeutic drugs for HCC are either poorly effective or expensive, and treatment with these drugs has not led to satisfactory outcomes. In a 2012 case report, we described our breakthrough finding in two advanced HCC patients, of whom one achieved complete remission of liver tumors and the other a normalized α-fetoprotein level, along with complete remission of their lung metastases, after the concomitant use of thalidomide and cyproheptadine. We assumed the key factor in our effective therapy to be cyproheptadine. In this study, we investigated the antiproliferative effects and molecular mechanisms of cyproheptadine.

Methods

The effect of cyproheptadine on cell proliferation was examined in human HCC cell lines HepG2 and Huh-7. Cell viability was assayed with Cell Counting Kit-8; cell cycle distribution was analyzed by flow cytometry. Mechanisms underlying cyproheptadine-induced cell cycle arrest were probed by western blot analysis.

Results

Cyproheptadine had a potent inhibitory effect on the proliferation of HepG2 and Huh-7 cells but minimal toxicity in normal hepatocytes. Cyproheptadine induced cell cycle arrest in HepG2 cells in the G1 phase and in Huh-7 cells at the G1/S transition. The cyproheptadine-induced G1 arrest in HepG2 cells was associated with an increased expression of HBP1 and p16, whereas the G1/S arrest in Huh-7 cells was associated with an increase in p21 and p27 expression and a dramatic decrease in the phosphorylation of the retinoblastoma protein. Additionally, cyproheptadine elevated the percentage of Huh-7 cells in the sub-G1 population, increased annexin V staining for cell death, and raised the levels of PARP and its cleaved form, indicating induction of apoptosis. Finally, cyproheptadine-mediated cell cycle arrest was dependent upon the activation of p38 MAP kinase in HepG2 cells and the activation of both p38 MAP kinase and CHK2 in Huh-7 cells.

Conclusions

Our results demonstrate that a non-classical p38 MAP kinase function, regulation of cell cycle checkpoints, is one of the underlying mechanisms promoted by cyproheptadine to suppress the proliferation of HCC cells. These results provide evidence for the drug’s potential as a treatment option for liver cancer.

Electronic supplementary material

The online version of this article (doi:10.1186/s12885-015-1137-9) contains supplementary material, which is available to authorized users.

Cyproheptadine significantly improves the overall and progression-free survival of sorafenib-treated advanced HCC patients

Objective

Sorafenib is a recommended treatment for advanced hepatocellular carcinoma. The study is to evaluate the efficacy of sorafenib plus cyproheptadine compared with sorafenib alone in patients with advanced hepatocellular carcinoma.

Methods

A retrospective cohort study reviewed all consecutive advanced hepatocellular carcinoma cases with Child-Pugh Class A disease starting sorafenib treatment at our hospital from August 2012 to March 2013. They were followed up until 31 December 2013. A total of 52 patients were enrolled: 32 patients in the combination (sorafenib–cyproheptadine) group and 20 patients in the control (sorafenib alone) group. The response to treatment, overall survival and progression-free survival were compared.

Results

The median overall survival was 11.0 months (95% confidence interval: 6.8–15.1 months) in the combination group compared with 4.8 months (95% confidence interval: 3.1–6.6 months) in the control group (crude hazard ratio = 0.45, 95% confidence interval: 0.22–0.82). The median progression-free survival time was 7.5 months (95% confidence interval: 5.1–10.0 months) in the combination group compared with 1.7 months (95% confidence interval: 1.4–2.1 months) in the control group (crude hazard ratio = 0.43, 95% confidence interval: 0.22–0.86). Kaplan–Meier survival analysis revealed that both overall survival and progression-free survival in the combination group were significantly longer than that in the control group. The multivariate model found patients in the combination group were 76% less likely to die (adjusted hazard ratio = 0.24, 95% confidence interval: 0.10–0.58) and 82% less likely to have progression (adjusted hazard ratio = 0.18, 95% confidence interval: 0.08–0.44) during the 17 months of follow-up.

Conclusion

Cyproheptadine may significantly improve survival outcomes of sorafenib-treated advanced hepatocellular carcinoma patients.

Cyproheptadine-induced myeloma cell apoptosis is associated with inhibition of the PI3K/AKT signaling

Recent studies revealed that the anti-allergic cyproheptadine displays anti-blood cancer activity. However, its mechanism is still elusive. In this study, cyproheptadine was found to decrease the expression of anti-apoptotic proteins, including Bcl-2, Mcl-1, and XIAP. More importantly, cyproheptadine-induced apoptosis was accompanied by suppressing AKT activation in myeloma cells. In the subsequent study, cyproheptadine was found to inhibit insulin-like growth factor 1-triggered AKT activation in a time- and concentration-dependent manner. Specifically, cyproheptadine blocked AKT translocation from nuclei for phosphorylation. This inhibition led to suppressed activation of p70S6K and 4EBP1, two key downstream signaling proteins in the PI3K/AKT pathway. However, cyproheptadine did not display inhibition on activation of IGF-1R or STAT3, possible upstream signals of AKT activation. These results further demonstrated that cyproheptadine suppresses the PI3K/AKT signaling pathway, which is probably critical for cyproheptadine-induced MM cell apoptosis.

Unexpected remission of hepatocellular carcinoma (HCC) with lung metastasis to the combination therapy of thalidomide and cyproheptadine: report of two cases and a preliminary HCC cell line study

We reported two cases of hepatocellular carcinoma (HCC) with lung metastases who were treated with a combination of thalidomide and cyproheptadine. The use of cyproheptadine in these two cases was originally for skin itching. Follow-up CT images revealed a complete remission of HCC in both of them after treatment for 6 months and 6 weeks, respectively. A following experimental cell line study demonstrated that cyproheptadine effectively reduced the viability of two HCC cell lines.

Proteasome inhibition and combination therapy for non-Hodgkin's lymphoma: from bench to bedside

Although patients with B-cell non-Hodgkin's lymphoma (NHL) usually respond to initial conventional chemotherapy, they often relapse and mortality has continued to increase over the last three decades in spite of salvage therapy or high dose therapy and stem cell transplantation. Outcomes vary by subtype, but there continues to be a need for novel options that can help overcome chemotherapy resistance, offer new options as consolidation or maintenance therapy postinduction, and offer potentially less toxic combinations, especially in the elderly population. The bulk of these emerging novel agents for cancer treatment target important biological cellular processes. Bortezomib is the first in the class of proteasome inhibitors (PIs), which target the critical process of intracellular protein degradation or recycling and editing through the proteasome. Bortezomib is approved for the treatment of relapsed or refractory mantle cell lymphoma. The mechanisms of proteasome inhibition are very complex by nature (because they affect many pathways) and not fully understood. However, mechanisms of action shared by bortezomib and investigational PIs such as carfilzomib, marizomib, ONX-0912, and MLN9708 are distinct from those of other NHL treatments, making them attractive options for combination therapy. Preclinical evidence suggests that the PIs have additive and/or synergistic activity with a large number of agents both in vitro and in vivo, from cytotoxics to new biologicals, supporting a growing number of combination studies currently underway in NHL patients, as reviewed in this article. The results of these studies will help our understanding about how to best integrate proteasome inhibition in the management of NHL and continue to improve patient outcomes.

Resveratrol protects leukemic cells against cytotoxicity induced by proteasome inhibitors via induction of FOXO1 and p27Kip1

BACKGROUND

It was reported recently that resveratrol could sensitize a number of cancer cells to the antitumoral effects of some conventional chemotherapy drugs. The current study was designed to investigate whether resveratrol could sensitize leukemic cells to proteasome inhibitors.

METHODS

Leukemic cells were treated with MG132 alone or in combination with resveratrol. Cell viability was investigated using MTT assay, and induction of apoptosis and cell cycle distribution was measured using flow cytometry. Western blot and real-time RT-PCR were used to investigate the expression of FOXO1 and p27Kip1. CHIP was performed to investigate the binding of FOXO1 to the p27 Kip1 promoter.

RESULTS

Resveratrol strongly reduced cytotoxic activities of proteasome inhibitors against leukemic cells. MG132 in combination with resveratrol caused cell cycle blockade at G1/S transition via p27Kip1 accumulation. Knockdown of p27Kip1 using siRNA dramatically attenuated the protective effects of resveratrol on cytotoxic actions of proteasome inhibitors against leukemic cells. Resveratrol induced FOXO1 expression at the transcriptional level, while MG132 increased nuclear distribution of FOXO1. MG132 in combination with resveratrol caused synergistic induction of p27Kip1 through increased recruitment of FOXO1 on the p27Kip1 promoter.

CONCLUSIONS

Resveratrol may have the potential to negate the cytotoxic effects of proteasome inhibitors via regulation of FOXO1 transcriptional activity and accumulation of p27Kip1.

Targeting histone deacetyalses in the treatment of B- and T-cell malignancies

HDAC inhibitors (HDACI) are now emerging as one of the most promising new classes of drugs for the treatment of select forms of non-Hodgkin’s lymphoma (NHL). They are particularly active in T-cell lymphomas, possibly hodgkin’s lymphoma and indolent B cell lymphomas. Presently, two of these agents, vorinostat and romidepsin, have been approved in the US for the treatment of relapsed and refractory cutaneous T cell lymphomas (CTCL). Initially, these agents were developed with the idea that they affected transcriptional activation and thus gene expression, by modulating chromatin condensation and decondensation. It is now clear that their effects go beyond chromatin and by affecting the acetylation status of histones and other intra-cellular proteins, they modify gene expression and cellular function via multiple pathways. Gene expression profiles and functional genetic analysis has led to further understanding of the various molecular pathways that are affected by these agents including cell cycle regulation, pathways of cellular proliferation, apoptosis and angiogenesis all important in lymphomagenesis. There is also increasing data to support the effects of these agents on T cell receptor and immune function which may explain the high level of activity of these agents in T cell lymphomas and hodgkin’s lymphoma. There is ample evidence of epigenetic dysregulation in lymphomas which may underlie the mechanisms of action of these agents but how these agents work is still not clear. Current HDAC inhibitors can be divided into at least four classes based on their chemical structure. At present several of these HDAC inhibitors are in clinical trials both as single agents and in combination with chemotherapy or other biological agents. They are easy to administer and are generally well tolerated with minimal side effects. Different dosing levels and schedules and the use of isospecific HDAC inhibitors are some of the strategies that are being employed to increase the therapeutic effect of these agents in the treatment of lymphomas. There may also be class differences that translate into specific activity against different lymphoma. HDAC inhibitors will likely be incorporated into combinations of targeted therapies both in the upfront and relapsed setting for lymphomas.

Mantle cell lymphoma in relapse: the role of emerging new drugs

PURPOSE OF REVIEW

Despite current advances in the therapy for newly diagnosed mantle cell lymphoma (MCL), relapsed MCL continues to have a poor prognosis. Advances in our understanding of the molecular pathogenesis of MCL are yielding many promising novel therapies.

RECENT FINDINGS

This article reviews the unique biology of MCL and describes how our understanding of its cell cycle dysregulation, and impaired apoptotic pathways is yielding many potential therapeutic targets including cyclin D1 and the cell cycle regulatory proteins, inhibitors of mammalian target of rapamycin, the proteasome, and proapoptotic family members. Recent preclinical and clinical data with cdk inhibitors, histone deacetylase inhibitors, the proteasome inhibitor bortezomib, mammalian target of rapamycin inhibitors, and other experimental strategies such as immunotherapy and microRNA are discussed.

SUMMARY

Understanding these targeted therapies in the context of the biology of MCL, has the potential to develop novel therapeutic platforms for the treatment of relapsed MCL, and will hopefully change the outcome for patients with this challenging clinical condition.

Romidepsin and belinostat synergize the antineoplastic effect of bortezomib in mantle cell lymphoma

PURPOSE

Romidepsin and belinostat are inhibitors of histone deacetylases (HDACI). HDACIs are known to induce cell death in malignant cells through multiple mechanisms, including upregulation of death receptors and induction of cell cycle arrest. They are also known to be prodifferentiating. Mantle cell lymphoma (MCL) is an aggressive subtype of non-Hodgkin lymphoma characterized by the t(11;14)(q13;q32) translocation leading to the overexpression of cyclin D1.

EXPERIMENTAL DESIGN

Assays for cytotoxicty including mathematical analysis for synergism, flow-cytometry, immunoblottings, and a xenograft severe combined immunodeficient beige mouse model were used to explore the in vitro and in vivo activity of romidepsin and/or belinostat alone or in combination with the proteasome inhibitor bortezomib in MCL.

RESULTS

In vitro, romidepsin and belinostat exhibited concentration-dependent cytotoxicity against a panel of MCL cell lines. Both HDACI showed strong synergism when combined with the proteasome inhibitor bortezomib in MCL. An HDACI plus bortezomib also induced potent mitochondrial membrane depolarization and apoptosis, whereas no significant apoptosis was observed in peripheral blood mononuclear cells from healthy donors with the combination. These events were associated with a decrease in cyclin D1 and Bcl-X(L), and an increase in accumulation of acetylated histone H3, acetylated alpha-tubulin, and Noxa in cell lines. In a severe combined immunodeficient beige mouse model of MCL, the addition of belinostat to bortezomib enhanced efficacy compared with either drug alone.

CONCLUSIONS

Collectively, these data strongly suggest that HDACI such as romidepsin or belinostat in combination with a proteasome inhibitor could represent a novel and rationale platform for the treatment of MCL.