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1.
Blood ; 144(14): 1508-1520, 2024 Oct 03.
Article in English | MEDLINE | ID: mdl-39046770

ABSTRACT

ABSTRACT: The histone H3 at lysine 27 (H3K27) demethylase lysine demethylase 6A (KDM6A) is a tumor suppressor in multiple cancers, including multiple myeloma (MM). We created isogenic MM cells disrupted for KDM6A and tagged the endogenous protein to facilitate genome-wide studies. KDM6A binds genes associated with immune recognition and cytokine signaling. Most importantly, KDM6A binds and activates NLRC5 and CIITA, which encode regulators of major histocompatibility complex genes. Patient data indicate that NLRC5 and CIITA are downregulated in MM with low KDM6A expression. Chromatin analysis shows that KDM6A binds poised and active enhancers and KDM6A loss led to decreased H3K27ac at enhancers, increased H3K27me3 levels in body of genes bound by KDM6A, and decreased gene expression. Reestablishing histone acetylation with an HDAC3 inhibitor leads to upregulation of major histocompatibility complex expression, offering a strategy to restore immunogenicity of KDM6A-deficient tumors. Loss of Kdm6a in Kirsten rat sarcoma virus (K-RAS)-transformed murine fibroblasts led to increased growth in vivo associated with decreased T-cell infiltration.


Subject(s)
Gene Expression Regulation, Neoplastic , Histone Demethylases , Multiple Myeloma , Multiple Myeloma/genetics , Multiple Myeloma/immunology , Humans , Animals , Mice , Histone Demethylases/genetics , Histone Demethylases/metabolism , Intracellular Signaling Peptides and Proteins/genetics , Intracellular Signaling Peptides and Proteins/metabolism , Nuclear Proteins/genetics , Nuclear Proteins/immunology , Nuclear Proteins/metabolism , Cell Line, Tumor , Histones/metabolism , Histones/genetics , Trans-Activators
2.
Int J Mol Sci ; 19(9)2018 Sep 13.
Article in English | MEDLINE | ID: mdl-30217020

ABSTRACT

We previously discovered a novel sirtuin (SIRT) inhibitor, MHY2256, that exerts anticancer activity through p53 acetylation in MCF-7 human breast cancer cells. We investigated the anticancer activity of MHY2256 against hormone-related cancer, an endometrial cancer with a poor prognosis. The IC50 values of MHY2256 were shown to be much lower than those of salermide, a well-known SIRT inhibitor. Furthermore, MHY2256 significantly reduced the protein expression and activities of SIRT1, 2, and 3, with similar effects to salermide. Particularly, MHY2256 markedly inhibited tumor growth in a tumor xenograft mouse model of Ishikawa cancer cells. During the experimental period, there was no significant change in the body weight of mice treated with MHY2256. A detailed analysis of the sensitization mechanisms of Ishikawa cells revealed that late apoptosis was largely increased by MHY2256. Additionally, MHY2256 increased G1 arrest and reduced the number of cell cyclic-related proteins, suggesting that apoptosis by MHY2256 was achieved by cellular arrest. Particularly, p21 was greatly increased by MHY225656, suggesting that cell cycle arrest by p21 is a major factor in MHY2256 sensitization in Ishikawa cells. We also detected a significant increase in acetylated p53, a target protein of SIRT1, in Ishikawa cells after MHY2256 treatment. In a mouse xenograft model, MHY2256 significantly reduced tumor growth and weight without apparent side effects. These results suggest that MHY2256 exerts its anticancer activity through p53 acetylation in endometrial cancer and can be used for targeting hormone-related cancers.


Subject(s)
Apoptosis/drug effects , Autophagy/drug effects , Endometrial Neoplasms/metabolism , Histone Deacetylase Inhibitors/pharmacology , Sirtuin 1/metabolism , Tumor Suppressor Protein p53/metabolism , Acetylation/drug effects , Animals , Blotting, Western , Cell Cycle Checkpoints/drug effects , Cell Line, Tumor , Female , Flow Cytometry , Humans , Mice , Mice, Inbred BALB C , Mice, Nude
3.
J Org Chem ; 82(7): 3359-3367, 2017 04 07.
Article in English | MEDLINE | ID: mdl-28385021

ABSTRACT

The rhodium(III)-catalyzed redox-neutral coupling reaction of N-acyl ketimines generated in situ from 3-hydroxyisoindolinones with various activated olefins is described. This approach leads to the synthesis of bioactive spiroisoindolinone derivatives in moderate to high yields. In the case of internal olefins such as maleimides, maleates, fumarates, and cinnamates, spiroindanes were obtained by the [3 + 2] annulations reaction. In sharp contrast, acrylates and quinones displayed the ß-H elimination followed by Prins-type cyclization furnishing spiroindenes. The synthetic compounds were evaluated for in vitro anticancer activity against androgen-sensitive human prostate adenocarcinoma cells (LNCaP), human prostate adenocarcinoma cells (DU145), human endometrial adenocarcinoma cells (Ishikawa), human breast cancer cell (MCF-7), and triple negative human breast cancer cells (MDA-MB-231). Notably, quinone-containing spiroindenes displayed potent anticancer activity about 2- to 3-fold stronger than that of anticancer agent doxorubicin.


Subject(s)
Alkenes/chemistry , Antineoplastic Agents/pharmacology , Imines/chemistry , Isoindoles/pharmacology , Nitriles/chemistry , Rhodium/chemistry , Spiro Compounds/pharmacology , Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/chemistry , Catalysis , Cell Line, Tumor , Cell Proliferation/drug effects , Cyclization , Dose-Response Relationship, Drug , Drug Screening Assays, Antitumor , Humans , Isoindoles/chemical synthesis , Isoindoles/chemistry , Molecular Structure , Spiro Compounds/chemical synthesis , Spiro Compounds/chemistry , Structure-Activity Relationship
4.
J Org Chem ; 81(24): 12416-12425, 2016 12 16.
Article in English | MEDLINE | ID: mdl-27978756

ABSTRACT

The weakly coordinating ketone group directed C-H functionalizations of chromones, 1,4-naphthoquinones, and xanthones with various maleimides under rhodium(III) catalysis are described. These protocols efficiently provide a range of succinimide-containing chromones, naphthoquinones, and xanthones with excellent site selectivity and functional group compatibility. All synthetic compounds were screened for in vitro anticancer activity against human breast adenocarcinoma cell lines (MCF-7). In particular, compounds 7aa and 7ca with a naphthoquinone scaffold were found to be highly cytotoxic, with an activity competitive with anticancer agent doxorubicin.


Subject(s)
Antineoplastic Agents/pharmacology , Chromones/chemical synthesis , Naphthoquinones/chemical synthesis , Rhodium/chemistry , Succinimides/analysis , Xanthones/chemical synthesis , Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/chemistry , Carbon-13 Magnetic Resonance Spectroscopy , Catalysis , Cell Proliferation/drug effects , Chromones/chemistry , Chromones/pharmacology , Drug Screening Assays, Antitumor , Humans , MCF-7 Cells , Naphthoquinones/chemistry , Naphthoquinones/pharmacology , Proton Magnetic Resonance Spectroscopy , Reactive Oxygen Species/metabolism , Spectrometry, Mass, Electrospray Ionization , Xanthones/chemistry , Xanthones/pharmacology
5.
J Org Chem ; 81(20): 9878-9885, 2016 10 21.
Article in English | MEDLINE | ID: mdl-27680096

ABSTRACT

The rhodium(III)-catalyzed direct C-H functionalization of various indolines with 1,4,2-dioxazol-5-ones as new amidating agents is described. This transformation provides efficient preparation of C7-amidated indolines known to display potent anticancer activity. The synthetic compounds were evaluated for in vitro anticancer activity against human prostate adenocarcinoma cells (LNCaP), human endometrial adenocarcinoma cells (Ishikawa), and human ovarian carcinoma cells (SKOV3). Compound 4f was found to be highly cytotoxic, with activity competitive with that of anticancer agent doxorubicin.


Subject(s)
Amides/chemistry , Indicators and Reagents/chemistry , Indoles/chemistry , Rhodium/chemistry , Catalysis , Cell Line, Tumor , Cell Proliferation/drug effects , Drug Screening Assays, Antitumor , Female , Humans , Indoles/pharmacology , Male , Spectrum Analysis/methods
6.
J Org Chem ; 79(19): 9262-71, 2014 Oct 03.
Article in English | MEDLINE | ID: mdl-25225782

ABSTRACT

A ketone-assisted ruthenium-catalyzed selective amination of xanthones and chromones C-H bonds with sulfonyl azides is described. The reactions proceed efficiently with a broad range of substrates with excellent functional group compatibility. This protocol provides direct access to 1-aminoxanthones, 5-aminochromones, and 5-aminoflavonoid derivatives known to exhibit potent anticancer activity.


Subject(s)
Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/pharmacology , Azides/chemical synthesis , Azides/pharmacology , Chromones/chemical synthesis , Chromones/pharmacology , Flavonoids/chemical synthesis , Flavonoids/pharmacology , Ruthenium/chemistry , Xanthones/chemical synthesis , Xanthones/pharmacology , Amination , Antineoplastic Agents/chemistry , Azides/chemistry , Catalysis , Chromones/chemistry , Flavonoids/chemistry , Molecular Structure , Xanthones/chemistry
7.
Commun Biol ; 7(1): 481, 2024 Apr 19.
Article in English | MEDLINE | ID: mdl-38641668

ABSTRACT

Childhood Sjögren's disease represents critically unmet medical needs due to a complete lack of immunological and molecular characterizations. This study presents key immune cell subsets and their interactions in the periphery in childhood Sjögren's disease. Here we show that single-cell RNA sequencing identifies the subsets of IFN gene-enriched monocytes, CD4+ T effector memory, and XCL1+ NK cells as potential key players in childhood Sjögren's disease, and especially in those with recurrent parotitis, which is the chief symptom prompting clinical visits from young children. A unique cluster of monocytes with type I and II IFN-related genes is identified in childhood Sjögren's disease, compared to the age-matched control. In vitro regulatory T cell functional assay demonstrates intact functionality in childhood Sjögren's disease in contrast to reduced suppression in adult Sjögren's disease. Mapping this transcriptomic landscape and interplay of immune cell subsets will expedite the understanding of childhood Sjögren's disease pathogenesis and set the foundation for precision medicine.


Subject(s)
Sjogren's Syndrome , Adult , Child , Humans , Child, Preschool , Sjogren's Syndrome/genetics , Sjogren's Syndrome/diagnosis , T-Lymphocytes, Regulatory , Gene Expression Profiling , Transcriptome , Killer Cells, Natural
8.
bioRxiv ; 2024 Aug 26.
Article in English | MEDLINE | ID: mdl-39253438

ABSTRACT

Proteolysis targeting chimeras (PROTACs) are an emerging targeted cancer therapy approach, but wide-spread clinical use of PROTAC is limited due to poor cell targeting and penetration, and instability in vivo. To overcome such issues and enhance the in vivo efficacy of PROTAC drugs, microfluidic droplet-based electroporation (µDES) was developed as a novel extracellular vesicle (EVs) transfection system, which enables the high-efficient PROTAC loading and effective delivery in vivo. Our previously developed YX968 PROTAC drug had shown the selectively degradation of HDAC3 and 8, which effectively suppresses the growth of breast tumor cell lines, including MDA-MB-231 triple negative breast cancer (TNBC) line, via dual degradation without provoking a global histone hyperacetylation. In this study, we demonstrated that µDES-based PROTAC loading in EVs significantly enhanced therapeutic function of PROTAC drug in vivo in the TNBC breast tumor mouse model. NSG mice with pre-established MDA-MB-231 tumors and treated with intraperitoneal injection of EVs for tumor inhibition study, which showed significantly higher HDAC 3 and 8 degradation efficiency and tumor inhibition than PROTAC only group. The liver, spleen, kidney, lung, heart, and brain were collected for safety testing, which exhibited improved toxicity. The EV delivery of PROTAC drug enhances drug stability and bioavailability in vivo, transportability, and drug targeting ability, which fills an important gap in current development of PROTAC therapeutic functionality in vivo and clinical translation. This novel EV-based drug transfection and delivery strategy could be applicable to various therapeutics for enhancing in vivo delivery, efficacy, and safety.

9.
Cancer Res Commun ; 4(8): 2242-2254, 2024 Aug 01.
Article in English | MEDLINE | ID: mdl-39105498

ABSTRACT

Renal cell carcinoma (RCC), the most common form of kidney cancer, is a heterogeneous disease with clear cell RCC (ccRCC) being the most prevalent and aggressive subtype. While most ccRCC tumors have elevated expression of angiopoietin-like4 (ANGPTL4), in our study we identified a significant subset of patients whose cancers show no increase in ANGPTL4 expression. These patients have a worse prognosis compared to the patients with high expression of ANGPTL4. These ANGPTL4-low cancers are characterized by the increased frequency of wild-type Von Hippel-Lindau(WT VHL), a gene that is commonly mutated in ccRCC, and an enrichment for genes associated with lipid metabolism. Using RCC tumor models with WT VHL, we demonstrate that ANGPTL4 behaves as a tumor suppressor. The loss of ANGPTL4 in ccRCC cell lines results in increased tumor growth and colony formation in a lysosomal acid lipase (LAL)-dependent manner, a phenotype rescued by the expression of N-terminus ANGPTL4. At the mechanistic level, the loss of ANGPTL4 increases LAL activity in ccRCC cells. These data suggest that ANGPTL4 enacts its tumor-suppressive effects in ccRCC by regulating LAL activity. Importantly, the identified patient cohort with low ANGPTL4 expression may exhibit increased reliance on lipid metabolism, which can be a point of target for future therapy. SIGNIFICANCE: Our data indicate angiopoietin-like 4 (ANGPTL4) acts as a tumor suppressor in clear cell renal cell carcinoma via regulating lipid metabolism and identifies a cohort of patients with lower expression of ANGPTL4 that are correlated with shorter survival.


Subject(s)
Angiopoietin-Like Protein 4 , Carcinoma, Renal Cell , Kidney Neoplasms , Sterol Esterase , Animals , Female , Humans , Mice , Angiopoietin-Like Protein 4/genetics , Angiopoietin-Like Protein 4/metabolism , Carcinoma, Renal Cell/pathology , Carcinoma, Renal Cell/genetics , Carcinoma, Renal Cell/metabolism , Cell Line, Tumor , Cell Proliferation , Gene Expression Regulation, Neoplastic , Kidney Neoplasms/pathology , Kidney Neoplasms/genetics , Kidney Neoplasms/metabolism , Prognosis , Sterol Esterase/genetics , Sterol Esterase/metabolism , Von Hippel-Lindau Tumor Suppressor Protein/genetics , Von Hippel-Lindau Tumor Suppressor Protein/metabolism
10.
bioRxiv ; 2024 Jun 29.
Article in English | MEDLINE | ID: mdl-38979295

ABSTRACT

Tobacco smoke remains a serious global issue, resulting in serious health complications, contributing to the onsets of numerous preventive diseases, and imposing significant financial burdens. Despite regulatory policies and cessation measures aimed at curbing its usage, novel interventions are urgently needed for effective damage reduction. Our preclinical and pilot clinical studies showed that AB-free kava has the potential to reduce tobacco smoke-induced lung cancer risk, mitigate tobacco dependence, and reduce tobacco use. To understand the scope of its benefits in damage reduction and potential limitations, this study evaluated the effects of AB-free kava on a panel of health indicators in mice exposed to 2 - 4 weeks of daily tobacco smoke exposure. Our comprehensive assessments included global transcriptional profiling of the lung and liver tissues, analysis of lung inflammation, evaluation of lung function, exploration of tobacco nicotine withdrawal, and characterization of the causal PKA signaling pathway. As expected, Tobacco smoke exposure perturbed a wide range of biological processes and compromised multiple functions in mice. Remarkably, AB-free kava demonstrated the ability to globally mitigate tobacco smoke-induced deficits at the molecular and functional levels with promising safety profiles, offering a unique promise to mitigate tobacco smoke-related health damages. Further pre-clinical evaluation and clinical translation are warranted to fully harness the potential of AB-free kava in combating tobacco smoke-related harms.

11.
bioRxiv ; 2024 Feb 12.
Article in English | MEDLINE | ID: mdl-38405853

ABSTRACT

The histone H3K27 demethylase KDM6A is a tumor suppressor in multiple cancers, including multiple myeloma (MM). We created isogenic MM cells disrupted for KDM6A and tagged the endogenous protein to facilitate genome wide studies. KDM6A binds genes associated with immune recognition and cytokine signaling. Most importantly, KDM6A binds and activates NLRC5 and CIITA encoding regulators of Major Histocompatibility Complex (MHC) genes. Patient data indicate that NLRC5 and CIITA, are downregulated in MM with low KDM6A expression. Chromatin analysis shows that KDM6A binds poised and active enhancers and KDM6A loss led to decreased H3K27ac at enhancers, increased H3K27me3 levels in body of genes bound by KDM6A and decreased gene expression. Reestablishing histone acetylation with an HDAC3 inhibitor leads to upregulation of MHC expression, offering a strategy to restore immunogenicity of KDM6A deficient tumors. Loss of Kdm6a in murine RAS-transformed fibroblasts led to increased growth in vivo associated with decreased T cell infiltration. Statement of significance: We show that KDM6A participates in immune recognition of myeloma tumor cells by directly regulating the expression of the master regulators of MHC-I and II, NLRC5 and CIITA. The expression of these regulators can by rescued by the HDAC3 inhibitors in KDM6A-null cell lines.

12.
J Exp Med ; 221(3)2024 Mar 04.
Article in English | MEDLINE | ID: mdl-38334978

ABSTRACT

An effective cancer therapy requires killing cancer cells and targeting the tumor microenvironment (TME). Searching for molecules critical for multiple cell types in the TME, we identified NR4A1 as one such molecule that can maintain the immune suppressive TME. Here, we establish NR4A1 as a valid target for cancer immunotherapy and describe a first-of-its-kind proteolysis-targeting chimera (PROTAC, named NR-V04) against NR4A1. NR-V04 degrades NR4A1 within hours in vitro and exhibits long-lasting NR4A1 degradation in tumors with an excellent safety profile. NR-V04 inhibits and frequently eradicates established tumors. At the mechanistic level, NR-V04 induces the tumor-infiltrating (TI) B cells and effector memory CD8+ T (Tem) cells and reduces monocytic myeloid-derived suppressor cells (m-MDSC), all of which are known to be clinically relevant immune cell populations in human melanomas. Overall, NR-V04-mediated NR4A1 degradation holds promise for enhancing anticancer immune responses and offers a new avenue for treating various types of cancers such as melanoma.


Subject(s)
Melanoma , Myeloid-Derived Suppressor Cells , Humans , Cell Line, Tumor , Immunotherapy , Melanoma/pathology , Myeloid-Derived Suppressor Cells/pathology , Nuclear Receptor Subfamily 4, Group A, Member 1/metabolism , Tumor Microenvironment , Proteolysis Targeting Chimera
13.
Cell Death Discov ; 9(1): 1, 2023 Jan 02.
Article in English | MEDLINE | ID: mdl-36588105

ABSTRACT

Small-cell lung cancer (SCLC) is an aggressive malignancy with limited therapeutic options. The dismal prognosis in SCLC is in part associated with an upregulation of BCL-2 family anti-apoptotic proteins, including BCL-XL and MCL-1. Unfortunately, the currently available inhibitors of BCL-2 family anti-apoptotic proteins, except BCL-2 inhibitors, are not clinically relevant because of various on-target toxicities. We, therefore, aimed to develop an effective and safe strategy targeting these anti-apoptotic proteins with DT2216 (our platelet-sparing BCL-XL degrader) and AZD8055 (an mTOR inhibitor) to avoid associated on-target toxicities while synergistically optimizing tumor response. Through BH3 mimetic screening, we identified a subset of SCLC cell lines that is co-dependent on BCL-XL and MCL-1. After screening inhibitors of selected tumorigenic pathways, we found that AZD8055 selectively downregulates MCL-1 in SCLC cells and its combination with DT2216 synergistically killed BCL-XL/MCL-1 co-dependent SCLC cells, but not normal cells. Mechanistically, the combination caused BCL-XL degradation and suppression of MCL-1 expression, and thus disrupted MCL-1 interaction with BIM leading to an enhanced apoptotic induction. In vivo, the DT2216 + AZD8055 combination significantly inhibited the growth of cell line-derived and patient-derived xenografts and reduced tumor burden accompanied by increased survival in a genetically engineered mouse model of SCLC without causing appreciable thrombocytopenia or other normal tissue injuries. Thus, these preclinical findings lay a strong foundation for future clinical studies to test DT2216 + mTOR inhibitor combinations in a subset of SCLC patients whose tumors are co-driven by BCL-XL and MCL-1.

14.
Arch Toxicol ; 86(12): 1885-97, 2012 Dec.
Article in English | MEDLINE | ID: mdl-22885791

ABSTRACT

Melamine-induced renal toxicity is associated with crystal formation in the kidney following exposure to melamine and cyanuric acid. However, metabolomic profiling of intact kidney tissue after chronic intake of melamine and cyanuric acid (M + CA) mixtures has rarely been studied. The present study investigated the melamine-induced renal toxicity by determining metabolites in the kidney through [(1)H]nuclear magnetic resonance. Melamine (63 mg/kg) and cyanuric acid (6.3 mg/kg) were co-administered to rats via oral gavage for 30 days. The mixture of M + CA (63/6.3 mg/kg) induced nephrotoxicity, as determined by increased blood urea nitrogen (BUN) and creatinine levels. The kidney weights were significantly increased in the animals treated with M + CA (63/6.3 mg/kg). The histological analysis revealed epithelial degeneration and necrotic cell death in the proximal and distal tubules. Furthermore, various metabolites were altered in both renal medullar and cortical tissues. In the medullar tissues, asparagine, choline, creatinine, cysteine, ethanolamine, glucose, isoleucine, glutamine, and myo-inositol levels were elevated, but glucitol, phenylalanine, tyrosine, and sn-glycero-3-levels were reduced. In the cortex, ethanolamine, hypoxanthine, isoleucine and o-phosphoethanolamine levels were increased, whereas formate, glucose, glutathione, threonine, and myo-inositol levels were decreased, suggesting the M + CA-induced renal cell injury. These data suggest that a mixture of M + CA-induced metabolites may be useful biomarkers for the detection of kidney injury.


Subject(s)
Biomarkers/blood , Biomarkers/urine , Kidney Diseases/chemically induced , Kidney Diseases/pathology , Metabolomics/methods , Triazines/toxicity , Animals , Blood Chemical Analysis , Blotting, Western , Body Weight/drug effects , Immunohistochemistry , Kidney/pathology , Magnetic Resonance Spectroscopy , Male , Multivariate Analysis , Organ Size/drug effects , Principal Component Analysis , Rats , Rats, Sprague-Dawley , Urinalysis
15.
Nat Commun ; 12(1): 1281, 2021 02 24.
Article in English | MEDLINE | ID: mdl-33627663

ABSTRACT

Regulatory T cells (Tregs) play an important role in maintaining immune homeostasis and, within tumors, their upregulation is common and promotes an immunosuppressive microenvironment. Therapeutic strategies that can eliminate Tregs in the tumor (i.e., therapies that do not run the risk of affecting normal tissues), are urgently needed for the development of cancer immunotherapies. Here we report our discovery of B-cell lymphoma extra-large (BCL-XL) as a potential molecular target of tumor-infiltrating (TI) Tregs. We show that pharmacological degradation of BCL-XL using a newly developed platelet-sparing BCL-XL Proteolysis-targeting chimera (PROTAC) induces the apoptosis of TI-Tregs and the activation of TI-CD8+ T cells. Moreover, these activities result in an effective suppression of syngeneic tumor growth in immunocompetent, but not in immunodeficient or CD8+ T cell-depleted mice. Notably, treatment with BCL-XL PROTAC does not cause detectable damage within several normal tissues or thrombocytopenia. These findings identify BCL-XL as a target in the elimination of TI-Tregs as a component of cancer immunotherapies, and that the BCL-XL-specific PROTAC has the potential to be developed as a therapeutic for cancer immunotherapy.


Subject(s)
Lymphocytes, Tumor-Infiltrating/metabolism , T-Lymphocytes, Regulatory/metabolism , Animals , CRISPR-Cas Systems/genetics , CRISPR-Cas Systems/physiology , Cell Survival/genetics , Cell Survival/physiology , Cells, Cultured , Female , Flow Cytometry , Immunoblotting , Mice , Mice, Inbred C57BL , Proteolysis , bcl-X Protein/genetics , bcl-X Protein/metabolism
16.
Nat Commun ; 12(1): 5764, 2021 10 01.
Article in English | MEDLINE | ID: mdl-34599187

ABSTRACT

Regulatory T (Treg) cells are one of the major immunosuppressive cell types in cancer and a potential target for immunotherapy, but targeting tumor-infiltrating (TI) Treg cells has been challenging. Here, using single-cell RNA sequencing of immune cells from renal clear cell carcinoma (ccRCC) patients, we identify two distinct transcriptional fates for TI Treg cells, Fate-1 and Fate-2. The Fate-1 signature is associated with a poorer prognosis in ccRCC and several other solid cancers. CD177, a cell surface protein normally expressed on neutrophil, is specifically expressed on Fate-1 TI Treg cells in several solid cancer types, but not on other TI or peripheral Treg cells. Mechanistically, blocking CD177 reduces the suppressive activity of Treg cells in vitro, while Treg-specific deletion of Cd177 leads to decreased tumor growth and reduced TI Treg frequency in mice. Our results thus uncover a functional CD177+ TI Treg population that may serve as a target for TI Treg-specific immunotherapy.


Subject(s)
GPI-Linked Proteins/metabolism , Homeostasis , Isoantigens/metabolism , Lymphocytes, Tumor-Infiltrating/metabolism , Receptors, Cell Surface/metabolism , T-Lymphocytes, Regulatory/metabolism , Animals , Base Sequence , Carcinogenesis/genetics , Carcinogenesis/pathology , Carcinoma, Renal Cell/genetics , Carcinoma, Renal Cell/immunology , Carcinoma, Renal Cell/pathology , GPI-Linked Proteins/deficiency , Gene Expression Profiling , Gene Expression Regulation, Neoplastic , Humans , Kidney Neoplasms/genetics , Kidney Neoplasms/immunology , Kidney Neoplasms/pathology , Mice, Knockout , Prognosis , Receptors, Cell Surface/deficiency , Single-Cell Analysis , Transcription, Genetic
17.
Food Chem Toxicol ; 123: 492-500, 2019 Jan.
Article in English | MEDLINE | ID: mdl-30458268

ABSTRACT

Plumbagin (5-hydroxy-2-methyl-1,4-naphthaquinone) has displayed antitumor activity in vitro and in animal models; however, the underlying molecular mechanisms have not been fully explored. The aim of this study was to investigate the anticancer effects of plumbagin isolated from Nepenthes alata against MCF-7 breast cancer cells. We examined the cytotoxicity, cell cycle regulation, apoptotic cell death, and generation of intracellular reactive oxygen species (ROS) in MCF-7 cells. Plumbagin exhibited potent cytotoxicity in MCF-7 cells (wild-type p53) compared to that in SK-OV-3 (null-type) human epithelial ovarian cancer cells. Specifically, plumbagin upregulated the expression of p21CIP1/WAF1 in MCF-7 cells, causing cell cycle arrest in the G2/M phase through inhibition of cyclin B1 levels. Plumbagin also significantly increased the ratio of Bax/Bcl-2 and release of cytochrome c, resulting in apoptotic cell death in MCF-7 cells. Furthermore, plumbagin dramatically increased the intracellular ROS level, whereas pretreatment with the ROS scavenger N-acetyl cysteine protected against plumbagin-induced cytotoxicity, suggesting that ROS formation plays a pivotal role in antitumor activity in MCF-7 cells. In mice bearing MCF-7 cell xenografts, plumbagin significantly reduced tumor growth and weight without apparent side effects. We therefore concluded that plumbagin exerts anticancer activity against MCF-7 cells through the generation of intracellular ROS, resulting in the induction of apoptosis via a p53-dependent pathway. This study thus identifies a new anticancer mechanism of plumbagin against p53-dependent breast cancer cells and suggests a novel strategy for overcoming of breast cancer therapy.


Subject(s)
Antineoplastic Agents, Phytogenic/administration & dosage , Apoptosis/drug effects , Breast Neoplasms/drug therapy , Caryophyllales/chemistry , Naphthoquinones/administration & dosage , Tumor Suppressor Protein p53/metabolism , Animals , Antineoplastic Agents, Phytogenic/chemistry , Antineoplastic Agents, Phytogenic/isolation & purification , Breast Neoplasms/genetics , Breast Neoplasms/metabolism , Breast Neoplasms/physiopathology , Cell Cycle/drug effects , Cell Line, Tumor , Cell Proliferation/drug effects , Female , Humans , MCF-7 Cells , Mice, Inbred BALB C , Mice, Nude , Naphthoquinones/chemistry , Naphthoquinones/isolation & purification , Reactive Oxygen Species/metabolism , Tumor Suppressor Protein p53/genetics
18.
Dalton Trans ; 47(44): 15873-15881, 2018 Nov 13.
Article in English | MEDLINE | ID: mdl-30358775

ABSTRACT

Five mononuclear cyclometalated iridium complexes [1](PF6)-[5](PF6) were prepared using imidazole-based ligands of varying alkyl chain length. The complexes were characterised by various analytical techniques. The single crystal X-ray structures of [2](PF6), [3](PF6) and [4](PF6) revealed the expected distorted Oh structures around the metal centre; however, the chain length was found to play a crucial role in deciding the overall geometry. Theoretical investigations demonstrated that the HOMOs were mainly contributed by iridium and cyclometalated ligands, whereas the LUMOs were constituted from bpy/phen units. The complexes were found to be luminescent with a moderate emission quantum yield and lifetime in CH3CN. The in vitro growth inhibition assay of the complexes with a shorter alkyl chain ([4]+ and [5]+) displayed higher anticancer activity (IC50 < 0.5 µM) compared to the complexes with a longer alkyl chain ([1]+-[3]+) (IC50 < 30 µM) against human breast cancer (MCF-7) cells. The complexes [4]+ and [5]+ also displayed moderate cancer cell selectivity (∼3 times) over normal breast (MCF-10) cells. The flow cytometry assay and fluorescence microscopy analysis suggested that cellular accumulation was primarily responsible for the variation in anticancer activity. Interestingly, without possessing any anticancer activity or toxicity ((IC50 > 50 µM), the complex [1]+ mainly accumulated near the cell membrane outside the cell and displayed a clear image of the cell membrane. The light microscopy images and western blot analysis reveal that complex [4]+ induced combined apoptosis and paraptosis. Thus, tuning the anticancer activity and cellular imaging property mediated by the alkyl chain would be of great importance and would be useful in anticancer research.


Subject(s)
Antineoplastic Agents/pharmacology , Coordination Complexes/pharmacology , Iridium/pharmacology , Molecular Imaging , Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/chemistry , Cell Line , Cell Membrane/chemistry , Cell Proliferation/drug effects , Cell Survival/drug effects , Coordination Complexes/chemical synthesis , Coordination Complexes/chemistry , Crystallography, X-Ray , Density Functional Theory , Dose-Response Relationship, Drug , Drug Screening Assays, Antitumor , Humans , Iridium/chemistry , MCF-7 Cells , Microscopy, Fluorescence , Models, Molecular , Molecular Structure , Optical Imaging , Structure-Activity Relationship
19.
Food Chem Toxicol ; 114: 11-22, 2018 Apr.
Article in English | MEDLINE | ID: mdl-29438775

ABSTRACT

The detoxifying effect of pyridoxine against acetaminophen (APAP)-induced hepatotoxicity was investigated. HepG2 cells were co-treated with APAP and pyridoxine to compare with betaine or methionine for 24 h. LDH, ALT and AST activities were measured to determine direct cells damage in vitro and in vivo. Lipid peroxidation, antioxidant enzymes activity, and glutathione level were measured. Cytochrome c releaseand procaspase-3, cleaved caspase-3, Bcl-2, or Bax protein levels were measured to determine APAP-induced apoptotic cell death. Pyridoxine treatment significantly increased cell viability and decreased leakage of LDH activity against APAP-induced hepatotoxicity in HepG2 cells. ALT and AST activities were dose-dependently reduced by pyridoxine treatment compared to APAP-treated group. Significant increases in activities of GST and GPx were observed after co-treatment with APAP and pyridoxine. Although APAP-induced Nrf2 and HO-1 expression levels were gradually reduced in HepG2 cells by pyridoxine treatment, induction of antioxidant enzymes activities were dose-dependently increased. These protected effects of pyridoxine against APAP-induced hepatoxicity were closely associated with suppression of APAP-induced oxidative stress and apoptotic cell death in HepG2 cells. These data indicated that the protective action of pyridoxine against hepatic cell injuries was involved in the direct antioxidant activity which provides a pivotal mechanism for its potential hepatoprotective action.


Subject(s)
Acetaminophen/adverse effects , Chemical and Drug Induced Liver Injury/drug therapy , Oxidative Stress/drug effects , Pyridoxine/administration & dosage , Alanine Transaminase/metabolism , Animals , Aspartate Aminotransferases/metabolism , Chemical and Drug Induced Liver Injury/etiology , Chemical and Drug Induced Liver Injury/metabolism , Cytochromes c/metabolism , Glutathione/metabolism , Glutathione Peroxidase/metabolism , Hep G2 Cells , Humans , Lipid Peroxidation/drug effects , Liver/drug effects , Liver/enzymology , Liver/metabolism , Male , Malondialdehyde/metabolism , Mice, Inbred ICR
20.
Cancer Med ; 7(10): 5083-5095, 2018 10.
Article in English | MEDLINE | ID: mdl-30160042

ABSTRACT

Current clinical trials of new anticancer therapies against metastatic renal cell carcinoma (RCC), including molecular-targeted therapies, have not shown promise. The purpose of this study was to preclinically assess the antitumor effects of MC-4, a partially purified material of Artemisia annua L., as a monotherapy or in combination with the known mechanistic target of rapamycin complex 1 (mTORC1) inhibitor, everolimus, against Caki-1 (Von Hippel-Lindau (VHL)+/+) and 786-O (VHL-/-) human RCC cells. MC-4 monotherapy significantly increased tumor growth inhibition and autophagic cell death in RCC cells in vitro and in vivo. Everolimus led to compensatory Akt activation by inhibiting only mTORC1 signaling pathway. In contrast to everolimus, MC-4 enhanced phosphatase and tensin homolog expression and reduced its downstream effector, Akt/pyruvate kinase muscle isozyme M2 (PKM2), leading to decreased expression of glucose transporter 1, which is associated with cancer cell metabolism. The synergistic antitumor and anti-metastatic effects induced by co-administration of MC-4 and everolimus involve cell growth inhibition and autophagic cell death via dual targeting of phosphatidylinositol 3-kinase (PI3K)/Akt/PKM2 and mTORC1. These findings suggest that MC-4 is a novel Akt/PKM2 inhibitor that can overcome the limitation of existing mTOR inhibitors and can be considered a novel strategy to treat patients with rapidly progressing advanced RCC.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Artemisia annua/chemistry , Carcinoma, Renal Cell/drug therapy , Everolimus/administration & dosage , Kidney Neoplasms/drug therapy , Plant Extracts/administration & dosage , Animals , Antineoplastic Combined Chemotherapy Protocols/pharmacology , Carcinoma, Renal Cell/metabolism , Carrier Proteins/metabolism , Cell Line, Tumor , Cell Proliferation/drug effects , Cell Survival/drug effects , Everolimus/pharmacology , Female , Gene Expression Regulation, Neoplastic/drug effects , Humans , Kidney Neoplasms/metabolism , Mechanistic Target of Rapamycin Complex 1/metabolism , Membrane Proteins/metabolism , Mice , Plant Components, Aerial/chemistry , Plant Extracts/pharmacology , Proto-Oncogene Proteins c-akt/metabolism , Signal Transduction/drug effects , Thyroid Hormones/metabolism , Xenograft Model Antitumor Assays , Thyroid Hormone-Binding Proteins
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