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BioRxiv : the Preprint Server For... Jul 2020Guided by a computational docking analysis, about 30 FDA/EMA-approved small molecule medicines were characterized on their inhibition of the SARS-CoV-2 main protease...
Guided by a computational docking analysis, about 30 FDA/EMA-approved small molecule medicines were characterized on their inhibition of the SARS-CoV-2 main protease (M). Of these tested small molecule medicines, six displayed an IC value in inhibiting M below 100 μM. Three medicines pimozide, ebastine, and bepridil are basic small molecules. Their uses in COVID-19 patients potentiate dual functions by both raising endosomal pH to slow SARS-CoV-2 entry into the human cell host and inhibiting M in infected cells. A live virus-based microneutralization assay showed that bepridil inhibited cytopathogenic effect induced by SARS-CoV-2 in Vero E6 cells completely at and dose-dependently below 5 μM and in A549 cells completely at and dose-dependently below 6.25 μM. Therefore, the current study urges serious considerations of using bepridil in COVID-19 clinical tests.
PubMed: 32511370
DOI: 10.1101/2020.05.23.112235 -
Leukemia Jan 2023The patients with relapsed and refractory diffuse large B-cell lymphoma (DLBCL) have poor prognosis, and a novel and effective therapeutic strategy for these patients is...
The patients with relapsed and refractory diffuse large B-cell lymphoma (DLBCL) have poor prognosis, and a novel and effective therapeutic strategy for these patients is urgently needed. Although ubiquitin-specific protease 1 (USP1) plays a key role in cancer, the carcinogenic effect of USP1 in B-cell lymphoma remains elusive. Here we found that USP1 is highly expressed in DLBCL patients, and high expression of USP1 predicts poor prognosis. Knocking down USP1 or a specific inhibitor of USP1, pimozide, induced cell growth inhibition, cell cycle arrest and autophagy in DLBCL cells. Targeting USP1 by shRNA or pimozide significantly reduced tumor burden of a mouse model established with engraftment of rituximab/chemotherapy resistant DLBCL cells. Pimozide significantly retarded the growth of lymphoma in a DLBCL patient-derived xenograft (PDX) model. USP1 directly interacted with MAX, a MYC binding protein, and maintained the stability of MAX through deubiquitination, which promoted the transcription of MYC target genes. Moreover, pimozide showed a synergetic effect with etoposide, a chemotherapy drug, in cell and mouse models of rituximab/chemotherapy resistant DLBCL. Our study highlights the critical role of USP1 in the rituximab/chemotherapy resistance of DLBCL through deubiquitylating MAX, and provides a novel therapeutic strategy for rituximab/chemotherapy resistant DLBCL.
Topics: Animals; Mice; Humans; Rituximab; Pimozide; Lymphoma, Large B-Cell, Diffuse; Lymphoma, Non-Hodgkin; Ubiquitin-Specific Proteases; Antineoplastic Combined Chemotherapy Protocols
PubMed: 36352191
DOI: 10.1038/s41375-022-01747-2 -
International Journal of Molecular... Jan 2021As hyperprolactinemia is observed in patients with bromocriptine‑resistant prolactinoma, prolactin (PRL) has been implicated in the development of bromocriptine...
As hyperprolactinemia is observed in patients with bromocriptine‑resistant prolactinoma, prolactin (PRL) has been implicated in the development of bromocriptine resistance. Since PRL primarily mediates cell survival and drug resistance via the Janus kinase‑2 (JAK2)/signal transducer and activator of transcription 5A (STAT5) signaling pathway, the STAT5 inhibitor, pimozide, may inhibit cell proliferation and reverse bromocriptine resistance in prolactinoma cells. In the present study, compared with bromocriptine or pimozide alone, the combination of pimozide and bromocriptine exerted enhanced reduction in cell growth and proliferation, and increased apoptosis and cell cycle arrest in bromocriptine‑resistant prolactinoma cells. A reduction in phospho‑STAT5, cyclin D1 and B‑cell lymphoma extra‑large (Bcl‑xL) expression levels were observed in cells treated with the combination of drugs. In addition, pimozide suppressed spheroid formation of human pituitary adenoma stem‑like cells, and reduced the protein expression of the cancer stem cell markers, CD133 and nestin. Pimozide did not exert any additional antitumor activity in STAT5‑knockdown primary culture cells of human bromocriptine‑resistant prolactinomas. Furthermore, Pimozide combined with bromocriptine treatment significantly reduced human prolactinoma xenograft growth. Western blot and immunohistochemical analyses also demonstrated significant inhibition of cell proliferation and stem cell marker proteins in vivo. Collectively, these data indicated that pimozide treatment reduced prolactinoma growth by targeting both proliferating cells and stem cells, at least in part, by inhibiting the STAT5/Bcl‑xL and STAT5/cyclin D1 signaling pathways.
Topics: Animals; Bromocriptine; Cell Line, Tumor; Cyclin D1; Humans; Mice; Mice, Nude; Pimozide; Pituitary Neoplasms; Prolactinoma; Rats; STAT5 Transcription Factor; Signal Transduction; Xenograft Model Antitumor Assays; bcl-X Protein
PubMed: 33155660
DOI: 10.3892/ijmm.2020.4784 -
Nature Communications Apr 2022The low-voltage activated T-type calcium channels regulate cellular excitability and oscillatory behavior of resting membrane potential which trigger many physiological...
The low-voltage activated T-type calcium channels regulate cellular excitability and oscillatory behavior of resting membrane potential which trigger many physiological events and have been implicated with many diseases. Here, we determine structures of the human T-type Ca3.3 channel, in the absence and presence of antihypertensive drug mibefradil, antispasmodic drug otilonium bromide and antipsychotic drug pimozide. Ca3.3 contains a long bended S6 helix from domain III, with a positive charged region protruding into the cytosol, which is critical for T-type Ca channel activation at low voltage. The drug-bound structures clearly illustrate how these structurally different compounds bind to the same central cavity inside the Ca3.3 channel, but are mediated by significantly distinct interactions between drugs and their surrounding residues. Phospholipid molecules penetrate into the central cavity in various extent to shape the binding pocket and play important roles in stabilizing the inhibitor. These structures elucidate mechanisms of channel gating, drug recognition, and actions, thus pointing the way to developing potent and subtype-specific drug for therapeutic treatments of related disorders.
Topics: Calcium Channels, T-Type; Humans; Membrane Potentials
PubMed: 35440630
DOI: 10.1038/s41467-022-29728-0 -
MedComm Dec 2023Lung adenocarcinoma (LUAD) is the most common form of lung cancer, with a consistently low 5-year survival rate. Therefore, we aim to identify key genes involved in LUAD...
Lung adenocarcinoma (LUAD) is the most common form of lung cancer, with a consistently low 5-year survival rate. Therefore, we aim to identify key genes involved in LUAD progression to pave the way for targeted therapies in the future. BDH1 plays a critical role in the conversion between acetoacetate and β-hydroxybutyrate. The presence of β-hydroxybutyrate is essential for initiating lysine β-hydroxybutyrylation (Kbhb) modifications. Histone Kbhb at the H3K9 site is attributed to transcriptional activation. We unveiled that β-hydroxybutyrate dehydrogenase 1 (BDH1) is not only conspicuously overexpressed in LUAD, but it also modulates the overall intracellular Kbhb modification levels. The RNA sequencing analysis revealed leucine-rich repeat-containing protein 31 (LRRC31) as a downstream target gene regulated by BDH1. Ecologically expressed BDH1 hinders the accumulation of H3K9bhb in the transcription start site of LRRC31, consequently repressing the transcriptional expression of LRRC31. Furthermore, we identified potential BDH1 inhibitors, namely pimozide and crizotinib, which exhibit a synergistic inhibitory effect on the proliferation of LUAD cells exhibiting high expression of BDH1. In summary, this study elucidates the molecular mechanism by which BDH1 mediates LUAD progression through the H3K9bhb/LRRC31 axis and proposes a therapeutic strategy targeting BDH1-high-expressing LUAD, providing a fresh perspective for LUAD treatment.
PubMed: 38098610
DOI: 10.1002/mco2.449 -
Cell Death & Disease Feb 2020Osteosarcoma (OS) is the most common primary bone tumor that primarily affects children and adolescents. Studies suggested that dysregulation JAK/STAT signaling promotes...
Osteosarcoma (OS) is the most common primary bone tumor that primarily affects children and adolescents. Studies suggested that dysregulation JAK/STAT signaling promotes the development of OS. Cells treated with pimozide, a STAT5 inhibitor suppressed proliferation and colony formation and induced sub G0/G1 cell cycle arrest and apoptosis. There was a reduction in cyclin D1 and CDK2 expression and Rb phosphorylation, and activation of Caspase-3 and PARP cleavage. In addition, pimozide suppressed the formation of 3-dimensional osteospheres and growth of the cells in the Tumor in a Dish lung organoid system. Furthermore, there was a reduction in expression of cancer stem cell marker proteins DCLK1, CD44, CD133, Oct-4, and ABCG2. More importantly, it was the short form of DCLK1 that was upregulated in osteospheres, which was suppressed in response to pimozide. We further confirmed by flow cytometry a reduction in DCLK1+ cells. Moreover, pimozide inhibits the phosphorylation of STAT5, STAT3, and ERK in OS cells. Molecular docking studies suggest that pimozide interacts with STAT5A and STAT5B with binding energies of -8.4 and -6.4 Kcal/mol, respectively. Binding was confirmed by cellular thermal shift assay. To further understand the role of STAT5, we knocked down the two isoforms using specific siRNAs. While knockdown of the proteins did not affect the cells, knockdown of STAT5B reduced pimozide-induced necrosis and further enhanced late apoptosis. To determine the effect of pimozide on tumor growth in vivo, we administered pimozide intraperitoneally at a dose of 10 mg/kg BW every day for 21 days in mice carrying KHOS/NP tumor xenografts. Pimozide treatment significantly suppressed xenograft growth. Western blot and immunohistochemistry analyses also demonstrated significant inhibition of stem cell marker proteins. Together, these data suggest that pimozide treatment suppresses OS growth by targeting both proliferating cells and stem cells at least in part by inhibiting the STAT5 signaling pathway.
Topics: Animals; Apoptosis; Cell Proliferation; G1 Phase Cell Cycle Checkpoints; Humans; Neoplastic Stem Cells; Osteosarcoma; Pimozide; STAT5 Transcription Factor; Signal Transduction; Tumor Suppressor Proteins
PubMed: 32094348
DOI: 10.1038/s41419-020-2335-1 -
Drug Metabolism and Disposition: the... Nov 2020Pimozide is a dopamine receptor antagonist indicated for the treatment of Tourette syndrome. Prior in vitro studies characterized dealkylation of pimozide to...
Pimozide is a dopamine receptor antagonist indicated for the treatment of Tourette syndrome. Prior in vitro studies characterized dealkylation of pimozide to 1,3-dihydro-1-(4-piperidinyl)-2H-benzimidazol-2-one (DHPBI) via CYP3A4 and, to a lesser extent, CYP1A2 as the only notable routes of pimozide biotransformation. However, drug-drug interactions between pimozide and CYP2D6 inhibitors and genotype-dependent effects have since been observed. To reconcile these incongruities between the prior in vitro and in vivo studies, we characterized two novel pimozide metabolites: 5-hydroxypimozide and 6-hydroxypimozide. Notably, 5-hydroxypimozide was the major metabolite produced by recombinant CYP2D6 (K ∼82 nM, ∼0.78 pmol/min per picomoles), and DHPBI was the major metabolite produced by recombinant CYP3A4 (apparent K ∼1300 nM, ∼2.6 pmol/min per picomoles). Kinetics in pooled human liver microsomes (HLMs) for the 5-hydroxylation (K ∼2200 nM, ∼59 pmol/min per milligram) and dealkylation (K ∼3900 nM, ∼600 pmol/min per milligram) reactions were also determined. Collectively, formation of DHPBI, 5-hydroxypimozide, and 6-hydroxypimozide accounted for 90% of pimozide depleted in incubations of NADPH-supplemented pooled HLMs. Studies conducted in HLMs isolated from individual donors with specific cytochrome P450 isoform protein abundances determined via mass spectrometry revealed that 5-hydroxypimozide ( = 0.94) and 6-hydroxypimozide ( = 0.86) formation rates were correlated with CYP2D6 abundance, whereas the DHPBI formation rate ( = 0.98) was correlated with CYP3A4 abundance. Furthermore, the HLMs differed with respect to their capacity to form 5-hydroxypimozide relative to DHPBI. Collectively, these data confirm a role for CYP2D6 in pimozide clearance via 5-hydroxylation and provide an explanation for a lack of involvement when only DHPBI formation was monitored in prior in vitro studies. SIGNIFICANCE STATEMENT: Current genotype-guided dosing information in the pimozide label is discordant with available knowledge regarding the primary biotransformation pathways. Herein, we characterize the CYP2D6-dependent biotransformation of pimozide to previously unidentified metabolites. In human liver microsomes, formation rates for the novel metabolites and a previously identified metabolite were determined to be a function of CYP2D6 and CYP3A4 content, respectively. These findings provide a mechanistic basis for observations of genotype-dependent pimozide clearance in vivo.
Topics: Adult; Aged; Antipsychotic Agents; Biotransformation; Child; Cytochrome P-450 CYP2D6; Cytochrome P-450 CYP2D6 Inhibitors; Cytochrome P-450 CYP3A; Drug Interactions; Female; Humans; Male; Microsomes, Liver; Middle Aged; Pimozide; Recombinant Proteins; Tourette Syndrome; Young Adult
PubMed: 32847865
DOI: 10.1124/dmd.120.000188 -
Biological & Pharmaceutical Bulletin 2021T-Type Ca channels (T-channels), particularly Ca3.2, are now considered as therapeutic targets for treatment of intractable pain including visceral pain. Among existing...
T-Type Ca channels (T-channels), particularly Ca3.2, are now considered as therapeutic targets for treatment of intractable pain including visceral pain. Among existing medicines, bepridil, a multi-channel blocker, used for treatment of arrhythmia and angina, and pimozide, a dopamine D receptor antagonist, known as a typical antipsychotic, have potent T-channel blocking activity. We thus tested whether bepridil and pimozide could suppress visceral pain in mice. Colonic and bladder pain were induced by intracolonic administration of 2,4,6-trinitrobenzene sulfonic acid (TNBS) and systemic administration of cyclophosphamide (CPA), respectively. Referred hyperalgesia was assessed by von Frey test, and colonic hypersensitivity to distension by a volume load with intracolonic water injection and spontaneous bladder pain were evaluated by observing nociceptive behaviors in conscious mice. The mice exhibited referred hyperalgesia and colonic hypersensitivity to distension on day 6 after TNBS treatment. Systemic administration of bepridil at 10-20 mg/kg or pimozide at 0.1-0.5 mg/kg strongly reduced the referred hyperalgesia on the TNBS-induced referred hyperalgesia and colonic hypersensitivity to distension. CPA treatment caused bladder pain-like nociceptive behavior and referred hyperalgesia, which were reversed by bepridil at 10-20 mg/kg or pimozide at 0.5-1 mg/kg. Our data thus suggest that bepridil and pimozide, existing medicines capable of blocking T-channels, are useful for treatment of colonic and bladder pain, and serve as seeds for the development of new medicines for visceral pain treatment.
Topics: Analgesics; Animals; Bepridil; Calcium Channel Blockers; Calcium Channels, T-Type; Colitis; Cyclophosphamide; Cystitis; Dopamine D2 Receptor Antagonists; Female; Male; Mice; Pimozide; Trinitrobenzenesulfonic Acid; Visceral Pain
PubMed: 33642557
DOI: 10.1248/bpb.b20-00742 -
Cell Death & Disease Sep 2018Autophagy is a well-described degradation mechanism that promotes cell survival upon nutrient starvation and other forms of cellular stresses. In addition, there is...
Autophagy is a well-described degradation mechanism that promotes cell survival upon nutrient starvation and other forms of cellular stresses. In addition, there is growing evidence showing that autophagy can exert a lethal function via autophagic cell death (ACD). As ACD has been implicated in apoptosis-resistant glioblastoma (GBM), there is a high medical need for identifying novel ACD-inducing drugs. Therefore, we screened a library containing 70 autophagy-inducing compounds to induce ATG5-dependent cell death in human MZ-54 GBM cells. Here, we identified three compounds, i.e. loperamide, pimozide, and STF-62247 that significantly induce cell death in several GBM cell lines compared to CRISPR/Cas9-generated ATG5- or ATG7-deficient cells, pointing to a death-promoting role of autophagy. Further cell death analyses conducted using pharmacological inhibitors revealed that apoptosis, ferroptosis, and necroptosis only play minor roles in loperamide-, pimozide- or STF-62247-induced cell death. Intriguingly, these three compounds induce massive lipidation of the autophagy marker protein LC3B as well as the formation of LC3B puncta, which are characteristic of autophagy. Furthermore, loperamide, pimozide, and STF-62247 enhance the autophagic flux in parental MZ-54 cells, but not in ATG5 or ATG7 knockout (KO) MZ-54 cells. In addition, loperamide- and pimozide-treated cells display a massive formation of autophagosomes and autolysosomes at the ultrastructural level. Finally, stimulation of autophagy by all three compounds is accompanied by dephosphorylation of mammalian target of rapamycin complex 1 (mTORC1), a well-known negative regulator of autophagy. In summary, our results indicate that loperamide, pimozide, and STF-62247 induce ATG5- and ATG7-dependent cell death in GBM cells, which is preceded by a massive induction of autophagy. These findings emphasize the lethal function and potential clinical relevance of hyperactivated autophagy in GBM.
Topics: Apoptosis; Autophagosomes; Autophagy; Brain Neoplasms; Cell Line, Tumor; Endosomes; Glioblastoma; HT29 Cells; Humans; Loperamide; Lysosomes; Mechanistic Target of Rapamycin Complex 1; Microscopy, Electron; Microtubule-Associated Proteins; Phosphorylation; Pimozide; Pyridines; Reactive Oxygen Species; Ribosomal Protein S6 Kinases; Thiazoles
PubMed: 30250198
DOI: 10.1038/s41419-018-1003-1 -
Cancers Jul 2022Monoclonal antibodies targeting the PD-1/PD-L1 immune checkpoint have considerably improved the treatment of some cancers, but novel drugs, new combinations, and... (Review)
Review
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.
PubMed: 35884428
DOI: 10.3390/cancers14143368