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1.
Toxicol Res ; 40(4): 541-550, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39345752

RESUMO

This study aimed to investigate the neuroprotective effects of cerebroprotein hydrolysate (CPH) against oxidative stress-induced HT22 cell death. Additionally, the effect of antioxidants such as quercetin (QC) and N-acetyl-L-cysteine (NAC) on the neuroprotective activity of CPH was evaluated. The mouse-derived hippocampal neuronal cell line HT22 was pretreated with CPH or a mixture of CPH and QC or NAC. HT22 cell death was induced by either 10 mM glutamate, 2.5 µM amyloid-ß (Aß)25-35, and 300 µM cobalt chloride (CoCl2). As results, CPH effectively alleviated HT22 cell death induced by glutamate, Aß25-35, and CoCl2. In addition, CPH combination with QC augmented cell viability in both glutamate- and Aß25-35-stressed conditions but had no synergic effect on the CoCl2-stressed condition. The synergic effect of CPH and NAC combination was observed under all cell death conditions. The neuroprotective actions of CPH and its combinations with QC or NAC against various oxidative stress-induced HT22 cell deaths were demonstrated, providing a promising strategy for developing CPH preparations for the prevention and/or treatment of neurodegenerative diseases such as Alzheimer's disease.

2.
Int J Biol Sci ; 20(6): 1978-1991, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38617536

RESUMO

Loss of PTEN tumor suppressor is an important event during colorectal cancer (CRC) development and is a target for therapeutic exploitation. This study reports that bromodomain and extra-terminal motif (BET) is a synthetic lethal partner of PTEN in CRC. BET inhibition (BETi) selectively induced G1 cell cycle arrest and apoptosis in PTEN-/- CRC. Further, BETi selectively and dose-dependently suppressed the growth of PTEN-/- CRC tumor xenografts in mice and patient-derived organoids. Mechanistically, PTEN-deficient CRC cells elevated the level of cytoplasmic p21CIP1/WAF1 that is hyper-phosphorylated at Thr145 by AKT. BETi suppressed AKT activation in PTEN-deficient CRC cells, followed by the reduction in p21 phosphorylation at Thr145, thereby promoting its nuclear translocation. In addition, BETi suppressed MYC level and this in turn increased the total p21 level in the nuclei. Over-expression of a phospho-mimetic p21 mutant (T145D) significantly rescued the BETi effect on PTEN-deficient CRC. These results suggest that BETi has a dual action on p21: elevating the level of p21 by inhibiting MYC and converting the oncogenic (cytoplasmic) p21 into the tumor-suppressive (nuclear) p21 by inhibiting AKT. Taken together, this study identified the synthetic lethal interaction between PTEN and BET, and provides a potential actionable target for CRC with PTEN loss.


Assuntos
Neoplasias Colorretais , Mutações Sintéticas Letais , Humanos , Animais , Camundongos , Proteínas Proto-Oncogênicas c-akt , Fosforilação , Citoplasma , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , PTEN Fosfo-Hidrolase/genética
3.
Cytokine ; 174: 156439, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38134557

RESUMO

Neuregulin (NRG)-1 plays fundamental roles in several organ systems after binding to its receptors, ErbB2 and ErbB4. This study examines the role of NRG-1 in atopic dermatitis (AD), a chronic skin disease that causes dryness, pruritus, and inflammation. In mice administered Der p 38, the skin presents AD-like symptoms including filaggrin downregulation and infiltration of neutrophils and eosinophils. Noticeably, there is an increased expression of NRG-1, ErbB2, and ErbB4 in the skin. Upregulation of these proteins is significantly correlated to the clinical skin severity score. In human keratinocyte HaCaT cells, exposure to Der p 38 decreased filaggrin expression, and NRG-1 alone had no effect on the expression. However, co-treatment of Der p 38 with NRG-1 enhanced the filaggrin expression decreased by Der p 38. Pre-treatment with AG879 (an ErbB2 inhibitor) or ErbB4 siRNA blocked the recovery of filaggrin expression in the cells after co-treatment with Der p 38 and NRG-1. Der p 38 treatment enhanced the secretion of interleukin-6 (IL-6), IL-8, and monocyte chemoattractant protein-1 (MCP-1). Co-treatment of Der p 38 with NRG-1 lowered the cytokine secretion increased by Der p 38, although NRG-1 alone was not effective on cytokine alteration. Neutrophil apoptosis was not altered by NRG-1 or supernatants of cells treated with NRG-1, but the cell supernatants co-treated with Der p 38 and NRG-1 blocked the anti-apoptotic effects of Der p 38-treated supernatants on neutrophils, which was involved in the activation of caspase 9 and caspase 3. Taken together, we determined that NRG-1 has anti-inflammatory effects in AD triggered by Der p 38. These results will pave the way to understanding the functions of NRG-1 and in the future development of AD treatment.


Assuntos
Dermatite Atópica , Camundongos , Animais , Humanos , Dermatite Atópica/genética , Proteínas Filagrinas , Neuregulina-1/farmacologia , Neuregulina-1/metabolismo , Neuregulina-1/uso terapêutico , Queratinócitos/metabolismo , Pele/metabolismo , Citocinas/metabolismo , Receptor ErbB-4/metabolismo , Receptor ErbB-4/farmacologia , Anti-Inflamatórios/farmacologia
4.
Int J Biol Sci ; 19(13): 4020-4035, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37705743

RESUMO

Triple-negative breast cancer (TNBC) is an aggressive type of breast cancer where no effective therapy has been developed. Here, we report that the natural product ER translocon inhibitor ipomoeassin F is a selective inhibitor of TNBC cell growth. A proteomic analysis of TNBC cells revealed that ipomoeassin F significantly reduced the levels of ER molecular chaperones, including PDIA6 and PDIA4, and induced ER stress, unfolded protein response (UPR) and autophagy in TNBC cells. Mechanistically, ipomoeassin F, as an inhibitor of Sec61α-containing ER translocon, blocks ER translocation of PDIA6, inducing its proteasomal degradation. Silencing of PDIA6 or PDIA4 by RNA interferences or treatment with a small molecule inhibitor of the protein disulfide isomerases in TNBC cells successfully recapitulated the ipomoeassin F phenotypes, including the induction of ER stress, UPR and autophagy, suggesting that the reduction of PDIAs is the key mediator of the pharmacological effects of ipomoeassin F. Moreover, ipomoeassin F significantly suppressed TNBC growth in a mouse tumor xenograft model, with a marked reduction in PDIA6 and PDIA4 levels in the tumor samples. Our study demonstrates that Sec61α-containing ER translocon and PDIAs are potential drug targets for TNBC and suggests that ipomoeassin F could serve as a lead for developing ER translocon-targeted therapy for TNBC.


Assuntos
Neoplasias de Mama Triplo Negativas , Humanos , Animais , Camundongos , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Proteômica , Glicoconjugados , Modelos Animais de Doenças , Chaperonas Moleculares
5.
Int J Biol Sci ; 19(11): 3544-3557, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37496993

RESUMO

Colorectal cancer (CRC) driven by PTEN deficiency exhibits high risk of metastasis, advancement of tumor stages and chemotherapy resistance, where no effective therapy has been developed. In this study, we performed a synthetic lethal drug screening in CRC and found that PTEN-deficient CRC cells are highly vulnerable to MDM2 inhibition. MDM2 inhibitor treatment or its silencing selectively inhibited the growth of PTEN-deficient CRC in vitro and in mice models. Mechanistically, PTEN loss increased the level of active AKT and subsequently increased MDM2 phosphorylation, thereby limiting the p53 functions in PTEN-/- CRC cells. MDM2 inhibition in turn activated p53 in CRC, particularly in PTEN-/- CRC cells. The synthetic lethal effect of MDM2 inhibitor was largely dependent on p53, because p53 silenced cells or cells lacking p53 failed to exhibit synthetic lethality in PTEN-deficient cells. We further showed that MDM2 inhibition led to the p53-dependent reversal of Bcl2-Bax ratio, which contributed to mitochondria-mediated apoptotic cell death in PTEN-deficient CRC. This study suggests that pharmacological targeting of MDM2 could be a potential therapeutic strategy for PTEN-deficient CRC.


Assuntos
Antineoplásicos , Neoplasias Colorretais , Animais , Camundongos , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-mdm2/genética , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
6.
Phytochemistry ; 211: 113711, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37150434

RESUMO

During the screening of the cytotoxicity of rare Korean endemic plants, the extract of Thuja koraiensis Nakai displayed potent cytotoxicity against the adenocarcinomic human alveolar basal epithelial A549 cell line. Through a series of separations via column chromatography, three undescribed abietanes, an undescribed labdane along with a labdane, and a biflavonoid were purified from methylene chloride (CH2Cl2) fraction possessing a potent cytotoxic effect. Extensive 1D and 2D NMR spectroscopic data analyses, in combination with quantum chemical calculations were conducted to establish the planar and absolute configurations of thujakoraienes A-C. The chemical structure of thujakoraiene D was elucidated by spectroscopic data analysis and competing enantioselective acylation. Thujakoraienes A and C along with 7,7″-di-O-methylamentoflavone, showed cytotoxic effects on A549 cells, with IC50 values of 64.86, 47.97, and 16.14 µM, respectively. Finally, thujakoraiene C and 7,7″-di-O-methylamentoflavone were identified as potent cytotoxic compounds in A549 cells, followed by an additional cytotoxicity test in the normal human lung fibroblast MRC-5 cell line. This is the first study on the non-volatile chemicals in the extract of T. koraiensis and comparison of chemical profiles of T. orientalis and T. koraiensis.


Assuntos
Antineoplásicos , Diterpenos , Thuja , Humanos , Células A549 , Thuja/química , Estrutura Molecular , Antineoplásicos/farmacologia , Diterpenos/química , Extratos Vegetais/farmacologia , Linhagem Celular Tumoral
7.
J Microbiol Biotechnol ; 32(8): 1017-1025, 2022 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-35879294

RESUMO

Bone homeostasis is regulated by constant remodeling through osteogenesis by osteoblasts and osteolysis by osteoclasts and osteoporosis can be provoked when this balance is broken. Present pharmaceutical treatments for osteoporosis have harmful side effects and thus, our goal was to develop therapeutics from intrisincally safe natural products. Fucoidan is a polysaccharide extracted from many species of brown seaweed, with valuable pharmaceutical activities. To intensify the effect of fucoidan on bone homeostasis, we hydrolyzed fucoidan using AMG, Pectinex and Viscozyme. Of these, fucoidan biotransformed by Pectinex (Fu/Pec) powerfully inhibited the induction of tartrate-resistant acid phosphatase (TRAP) activity in osteoclasts differentiated from bone marrow macrophages (BMMs) by the receptor for activation of nuclear factor-κB ligand (RANKL). To investigate potential of lower molecular weight fucoidan it was separated into >300 kDa, 50-300 kDa, and <50 kDa Fu/Pec fractions by ultrafiltration system. The effects of these fractions on TRAP and alkaline phosphatase (ALP) activities were then examined in differentiated osteoclasts and MC3T3-E1 osteoblasts, respectively. Interestingly, 50-300 kDa Fu/Pec suppressed RANKL-induced osteoclasts differentiation from BMMs but did not synergistically enhance osteoblasts differentiation induced by osteogenic agents. In addition, this fraction inhibited the expressions of NFATc1, TRAP, OSCAR, and RANK, which are all key transcriptional factors involved in osteoclast differentiation, and those of Src, c-Fos and Mitf, as determined by RT-PCR. In conclusion, enzymatically low-molecularized 50-300 kDa Fu/Pec suppressed TRAP by downregulating RANKL-related signaling, contributing to the inhibition of osteoclasts differentiation, and represented a potential means of inducing bone remodeling in the background of osteoporosis.


Assuntos
Osteoclastos , Osteoporose , Diferenciação Celular , Humanos , Ligantes , NF-kappa B , Fatores de Transcrição NFATC , Osteogênese , Preparações Farmacêuticas , Polissacarídeos , Ligante RANK
8.
Oncogene ; 41(19): 2734-2748, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35393542

RESUMO

SMAD4 loss-of-function mutations have been frequently observed in colorectal cancer (CRC) and are recognized as a drug target for therapeutic exploitation. In this study, we performed a synthetic lethal drug screening with SMAD4-isogenic CRC cells and found that aurora kinase A (AURKA) inhibition is synthetic lethal with SMAD4 loss. Inhibition of AURKA selectively inhibited the growth of SMAD4-/- CRC in vitro and in vivo. Mechanistically, SMAD4 negatively regulated AURKA level, resulting in the significant elevation of AURKA in SMAD4-/- CRC cells. Inhibition of AURKA induced G2/M cell cycle delay in SMAD4+/+ CRC cells, but induced apoptosis in SMAD4-/- CRC cells. We further observed that a high level of AURKA in SMAD4-/- CRC cells led to abnormal mitotic spindles, leading to cellular aneuploidy. Moreover, SMAD4-/- CRC cells expressed high levels of spindle assembly checkpoint (SAC) proteins, suggesting the hyperactivation of SAC. The silencing of key SAC proteins significantly rescued the AURKA inhibition-induced cell death in SMAD4-/- cells, suggesting that SMAD4-/- CRC cells are hyper-dependent on AURKA activity for mitotic exit and survival during SAC hyperactivation. This study presents a unique synthetic lethal interaction between SMAD4 and AURKA and suggests that AURKA could be a potential drug target in SMAD4-deficient CRC.


Assuntos
Aurora Quinase A , Neoplasias Colorretais , Aurora Quinase A/genética , Aurora Quinase A/metabolismo , Pontos de Checagem do Ciclo Celular/genética , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Humanos , Pontos de Checagem da Fase M do Ciclo Celular/genética , Proteína Smad4/genética , Proteína Smad4/metabolismo , Mutações Sintéticas Letais
9.
Molecules ; 26(20)2021 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-34684684

RESUMO

Memory deterioration in Alzheimer's disease (AD) is thought to be underpinned by aberrant amyloid ß (Aß) accumulation, which contributes to synaptic plasticity impairment. Avenanthramide-C (Avn-C), a polyphenol compound found predominantly in oats, has a range of biological properties. Herein, we performed methanolic extraction of the Avns-rich fraction (Fr. 2) from germinated oats using column chromatography, and examined the effects of Avn-C on synaptic correlates of memory in a mouse model of AD. Avn-C was identified in Fr. 2 based on 1H-NMR analysis. Electrophysiological recordings were performed to examine the effects of Avn-C on the hippocampal long-term potentiation (LTP) in a Tg2576 mouse model of AD. Avn-C from germinated oats restored impaired LTP in Tg2576 mouse hippocampal slices. Furthermore, Avn-C-facilitated LTP was associated with changes in the protein levels of phospho-glycogen synthase kinase-3ß (p-GSK3ß-S9) and cleaved caspase 3, which are involved in Aß-induced synaptic impairment. Our findings suggest that the Avn-C extract from germinated oats may be beneficial for AD-related synaptic plasticity impairment and memory decline.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Hipocampo/efeitos dos fármacos , Potenciação de Longa Duração/efeitos dos fármacos , ortoaminobenzoatos/farmacologia , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Animais , Avena/química , Modelos Animais de Doenças , Glicogênio Sintase Quinase 3 beta/metabolismo , Hipocampo/metabolismo , Potenciação de Longa Duração/fisiologia , Masculino , Camundongos , Camundongos Transgênicos , Plasticidade Neuronal , Extratos Vegetais/farmacologia
10.
J Antibiot (Tokyo) ; 74(10): 677-686, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34163025

RESUMO

Precision cancer medicine is a tailored treatment approach for individual cancer patients with different genomic characteristics. Mutated or hyperactive oncogenes have served as main drug targets in current precision cancer medicine, while defective or inactivated tumor suppressors in general have not been considered as druggable targets. Synthetic lethality is one of very few approaches that enable to target defective tumor suppressors with pharmacological agents. Synthetic lethality exploits cancer cell dependency on a protein or pathway, which arises when the function of a tumor suppressor is defective. This approach has been proven to be effective in clinical settings since the successful clinical introduction of BRCA-PARP synthetic lethality for the treatment of breast and ovarian cancer with defective BRCA. Subsequently, large-scale screenings with RNAi, CRISPR/Cas9-sgRNAs, and chemical libraries have been applied to identify synthetic lethal partners of tumor suppressors. Natural products are an important source for the discovery of pharmacologically active small molecules. However, little effort has been made in the discovery of synthetic lethal small molecules from natural products. This review introduces recent advances in the discovery of natural products targeting cancer cell dependency and discusses potentials of natural products in the precision cancer medicine.


Assuntos
Antineoplásicos/farmacologia , Produtos Biológicos/farmacologia , Sistemas de Liberação de Medicamentos , Neoplasias/tratamento farmacológico , Animais , Antineoplásicos/química , Produtos Biológicos/química , Humanos
11.
Exp Mol Med ; 53(5): 835-847, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-34050264

RESUMO

Recent advances in high-throughput sequencing technologies and data science have facilitated the development of precision medicine to treat cancer patients. Synthetic lethality is one of the core methodologies employed in precision cancer medicine. Synthetic lethality describes the phenomenon of the interplay between two genes in which deficiency of a single gene does not abolish cell viability but combined deficiency of two genes leads to cell death. In cancer treatment, synthetic lethality is leveraged to exploit the dependency of cancer cells on a pathway that is essential for cell survival when a tumor suppressor is mutated. This approach enables pharmacological targeting of mutant tumor suppressors that are theoretically undruggable. Successful clinical introduction of BRCA-PARP synthetic lethality in cancer treatment led to additional discoveries of novel synthetic lethal partners of other tumor suppressors, including p53, PTEN, and RB1, using high-throughput screening. Recent work has highlighted aurora kinase A (AURKA) as a synthetic lethal partner of multiple tumor suppressors. AURKA is a serine/threonine kinase involved in a number of central biological processes, such as the G2/M transition, mitotic spindle assembly, and DNA replication. This review introduces synthetic lethal interactions between AURKA and its tumor suppressor partners and discusses the potential of AURKA inhibitors in precision cancer medicine.


Assuntos
Aurora Quinase A/genética , Aurora Quinase A/metabolismo , Biomarcadores Tumorais , Neoplasias/etiologia , Neoplasias/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Mutações Sintéticas Letais , Animais , Ensaios Clínicos como Assunto , Suscetibilidade a Doenças , Desenvolvimento de Medicamentos , Avaliação Pré-Clínica de Medicamentos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Terapia de Alvo Molecular , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Medicina de Precisão , Inibidores de Proteínas Quinases/uso terapêutico , Transdução de Sinais/efeitos dos fármacos , Resultado do Tratamento
12.
Nat Commun ; 12(1): 3046, 2021 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-34031426

RESUMO

Nasopharyngeal carcinoma (NPC) is a malignant head and neck cancer type with high morbidity in Southeast Asia, however the pathogenic mechanism of this disease is poorly understood. Using integrative pharmacogenomics, we find that NPC subtypes maintain distinct molecular features, drug responsiveness, and graded radiation sensitivity. The epithelial carcinoma (EC) subtype is characterized by activations of microtubule polymerization and defective mitotic spindle checkpoint related genes, whereas sarcomatoid carcinoma (SC) and mixed sarcomatoid-epithelial carcinoma (MSEC) subtypes exhibit enriched epithelial-mesenchymal transition (EMT) and invasion promoting genes, which are well correlated with their morphological features. Furthermore, patient-derived organoid (PDO)-based drug test identifies potential subtype-specific treatment regimens, in that SC and MSEC subtypes are sensitive to microtubule inhibitors, whereas EC subtype is more responsive to EGFR inhibitors, which is synergistically enhanced by combining with radiotherapy. Through combinational chemoradiotherapy (CRT) screening, effective CRT regimens are also suggested for patients showing less sensitivity to radiation. Altogether, our study provides an example of applying integrative pharmacogenomics to establish a personalized precision oncology for NPC subtype-guided therapies.


Assuntos
Carcinoma Nasofaríngeo/tratamento farmacológico , Carcinoma Nasofaríngeo/genética , Neoplasias Nasofaríngeas/tratamento farmacológico , Neoplasias Nasofaríngeas/genética , Farmacogenética/métodos , Avaliação Pré-Clínica de Medicamentos/métodos , Transição Epitelial-Mesenquimal , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Técnicas de Inativação de Genes , Humanos , Pessoa de Meia-Idade , Carcinoma Nasofaríngeo/patologia , Neoplasias Nasofaríngeas/patologia , Medicina de Precisão , Transcriptoma , Sequenciamento do Exoma
13.
Animals (Basel) ; 11(4)2021 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-33807460

RESUMO

This study examined the effects of Mentha arvensis (MA) and Geranium thunbergii (GT) extracts in drinking water on the production performance, egg quality, cholesterol content of egg yolk, proximate composition, and sensory qualities of egg and immunity parameters in laying hens. Ninety-six 28-week-old Hy-Line Brown layers were randomly divided into four dietary treatments for 16 weeks. The dietary treatments were (1) control, (2) T1 (0.01% 1 MA:1 GT), (3) T2 (0.05% 1 MA:1 GT), and (4) T3 (0.1% 1 MA:1 GT). Egg production increased significantly with increasing levels of MA and GT. The egg weight was increased in T2, and the feed intake was highest in T2 and T3 (p < 0.05). The Haugh unit and egg shape index were significantly better in T3 and the control than with other treatments (p < 0.05). The content of yolk cholesterol was significantly lower (p < 0.05) in T2 and T3. On the other hand, there were no significant differences in the egg proximate composition. A significant increase in the serum interleukin 6 (IL-6), tumor necrosis factor (TNFα) and immunoglobulins (IgG and IgA) concentration was observed in the birds fed plant extracts when compared to the control. On average, T2 and T3 showed significantly lower (p < 0.05) concentrations of NH3 gas from the feces as compared to the control. This study suggests that MA and GT supplementation could improve the laying performance, egg quality, and immunity, and decrease the egg yolk cholesterol content in a dose-dependent manner.

14.
Oncogene ; 40(5): 937-950, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33293694

RESUMO

The tumor suppressor SMAD4 is frequently mutated in colorectal cancer (CRC). However, no effective targeted therapies exist for CRC with SMAD4 loss. Here, we employed a synthetic lethality drug screening in isogenic SMAD4+/+ and SMAD4-/- HCT116 CRC cells and found that bromodomain and extra-terminal motif (BET) inhibitors, as selective drugs for the growth of SMAD4-/- HCT116 cells. BET inhibition selectively induced G1 cell cycle arrest in SMAD4-/- cells and this effect was accompanied by the reprogramming of the MYC-p21 axis. Mechanistically, SMAD4 is a transcription repressor of MYC, and MYC in turn represses p21 transcription. SMAD4-/- cells lost MYC repression ability, thereby causing the cells addicted to the MYC oncogenic signaling. BET inhibition significantly reduced MYC level and restored p21 expression in SMAD4-/- cells, inducing the selective growth arrest. The ectopic overexpression of MYC or the silencing of p21 could rescue the BET inhibitor-induced growth arrest in SMAD4-/- cells, verifying this model. Tumor xenograft mouse experiments further demonstrated the synthetic lethality interaction between BET and SMAD4 in vivo. Taken together, our data suggest that BET could be a potential drug target for the treatment of SMAD4-deficient CRC.


Assuntos
Antineoplásicos/farmacologia , Neoplasias Colorretais/tratamento farmacológico , Proteínas/genética , Proteínas Proto-Oncogênicas c-myc/genética , Proteína Smad4/genética , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Inibidor de Quinase Dependente de Ciclina p21/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Inativação Gênica/efeitos dos fármacos , Células HCT116 , Humanos , Camundongos , Proteínas/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos , Mutações Sintéticas Letais/genética , Ensaios Antitumorais Modelo de Xenoenxerto
15.
Nat Commun ; 11(1): 5105, 2020 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-33037191

RESUMO

RB1 mutational inactivation is a cancer driver in various types of cancer including lung cancer, making it an important target for therapeutic exploitation. We performed chemical and genetic vulnerability screens in RB1-isogenic lung cancer pair and herein report that aurora kinase A (AURKA) inhibition is synthetic lethal in RB1-deficient lung cancer. Mechanistically, RB1-/- cells show unbalanced microtubule dynamics through E2F-mediated upregulation of the microtubule destabilizer stathmin and are hypersensitive to agents targeting microtubule stability. Inhibition of AURKA activity activates stathmin function via reduced phosphorylation and facilitates microtubule destabilization in RB1-/- cells, heavily impacting the bipolar spindle formation and inducing mitotic cell death selectively in RB1-/- cells. This study shows that stathmin-mediated disruption of microtubule dynamics is critical to induce synthetic lethality in RB1-deficient cancer and suggests that upstream factors regulating microtubule dynamics, such as AURKA, can be potential therapeutic targets in RB1-deficient cancer.


Assuntos
Aurora Quinase A/genética , Neoplasias Pulmonares/genética , Microtúbulos/metabolismo , Proteínas de Ligação a Retinoblastoma/genética , Estatmina/metabolismo , Ubiquitina-Proteína Ligases/genética , Animais , Aurora Quinase A/antagonistas & inibidores , Aurora Quinase A/metabolismo , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Camundongos Nus , Microtúbulos/genética , Pirazóis/farmacologia , Pirimidinas/farmacologia , Proteínas de Ligação a Retinoblastoma/metabolismo , Estatmina/genética , Mutações Sintéticas Letais , Ubiquitina-Proteína Ligases/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
16.
Int J Biol Sci ; 16(11): 1774-1784, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32398948

RESUMO

PTEN, a tumor suppressor, is found loss of function in many cancers, including colorectal cancer. To identify the synthetic lethal compounds working with PTEN deficiency, we performed a synthetic lethality drug screening with PTEN-isogenic colorectal cancer cells. From the screening, we found that PTEN-/- colorectal cancer cells were sensitive to anacardic acid, a p300/CBP histone acetyltransferase (HAT) inhibitor. Anacardic acid significantly reduced the viability of PTEN-/- cells not in PTEN+/+ cells via inducing apoptosis. Inhibition of HAT activity of p300/CBP by anacardic acid reduced the acetylation of histones at the promoter region and inhibited the transcription of Hsp70 family of proteins. The down-regulation of Hsp70 family proteins led to the reduction of AKT-Hsp70 complex formation, AKT destabilization and decreased the level of phosphorylated AKT at Ser473, all of which are vital for the survival of PTEN-/- colorectal cells. The synthetic lethality effect of anacardic acid was further validated in tumor xenograft mice models, where PTEN-/- colorectal tumors showed greater sensitivity to anacardic acid treatment than PTEN+/+ tumors. These data suggest that anacardic acid induced synthetic lethality by inhibiting HAT activity of p300/CBP, thereby reducing Hsp70 transcription and destabilizing AKT in PTEN deficient colorectal cancer cells.


Assuntos
Ácidos Anacárdicos/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , PTEN Fosfo-Hidrolase/deficiência , Proteínas Proto-Oncogênicas c-akt , Fatores de Transcrição de p300-CBP/antagonistas & inibidores , Ácidos Anacárdicos/química , Ácidos Anacárdicos/farmacologia , Animais , Neoplasias Colorretais/patologia , Técnicas de Química Combinatória , Regulação para Baixo , Desenho de Fármacos , Descoberta de Drogas , Deleção de Genes , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Masculino , Camundongos , Neoplasias Experimentais , PTEN Fosfo-Hidrolase/metabolismo , Neoplasias da Próstata/tratamento farmacológico , Mutações Sintéticas Letais , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto , Fatores de Transcrição de p300-CBP/metabolismo
17.
Acta Pharm Sin B ; 10(4): 615-627, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32322466

RESUMO

Breast cancer susceptibility gene 1 (BRCA1) is a tumor suppressor gene, which is frequently mutated in breast and ovarian cancers. BRCA1 plays a key role in the homologous recombination directed DNA repair, allowing its deficiency to act as a therapeutic target of DNA damaging agents. In this study, we found that inhibition of the class I histone deacetylases (HDAC) exhibited synthetic lethality with BRCA1 deficiency in breast cancer cells. Transcriptome profiling and validation study showed that HDAC inhibition enhanced the expression of thioredoxin interaction protein (TXNIP), causing reactive oxygen species (ROS)-mediated DNA damage. This effect induced preferential apoptosis in BRCA1 -/- breast cancer cells where DNA repair system is compromised. Two animal experiments and gene expression-associated patients' survival analysis further confirmed in vivo synthetic lethality between BRCA1 and HDAC. Finally, the combination of inhibitors of HDAC and bromodomain and extra-terminal motif (BET), another BRCA1 synthetic lethality target that also works through oxidative stress-mediated DNA damage, showed a strong anticancer effect in BRCA1 -/- breast cancer cells. Together, this study provides a new therapeutic strategy for BRCA1-deficient breast cancer by targeting two epigenetic machineries, HDAC and BET.

18.
Int J Med Sci ; 17(4): 498-509, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32174780

RESUMO

S100A8 and S100A9 are important proteins in the pathogenesis of allergy. Asthma is an allergic lung disease, characterized by bronchial inflammation due to leukocytes, bronchoconstriction, and allergen-specific IgE. In this study, we examined the role of S100A8 and S100A9 in the interaction of cytokine release from bronchial epithelial cells, with constitutive apoptosis of neutrophils. S100A8 and S100A9 induce increased secretion of neutrophil survival cytokines such as MCP-1, IL-6 and IL-8. This secretion is suppressed by TLR4 inhibitor), LY294002, AKT inhibitor, PD98059, SB202190, SP600125, and BAY-11-7085. S100A8 and S100A9 also induce the phosphorylation of AKT, ERK, p38 MAPK and JNK, and activation of NF-κB, which were blocked after exposure to TLR4i, LY294002, AKTi, PD98059, SB202190 or SP600125. Furthermore, supernatants collected from bronchial epithelial cells after S100A8 and S100A9 stimulation suppressed the apoptosis of normal and asthmatic neutrophils. These inhibitory mechanisms are involved in suppression of caspase 9 and caspase 3 activation, and BAX expression. The degradation of MCL-1 and BCL-2 was also blocked by S100A8 and S100A9 stimulation. Essentially, neutrophil apoptosis was blocked by co-culture of normal and asthmatic neutrophils with BEAS-2B cells in the presence of S100A8 and S100A9. These findings will enable elucidation of asthma pathogenesis.


Assuntos
Asma/metabolismo , Calgranulina A/uso terapêutico , Calgranulina B/farmacologia , Apoptose/efeitos dos fármacos , Western Blotting , Caspase 3/metabolismo , Caspase 9/metabolismo , Linhagem Celular , Citocinas/metabolismo , Ensaio de Imunoadsorção Enzimática , Eosinófilos/efeitos dos fármacos , Eosinófilos/metabolismo , Humanos , Neutrófilos/efeitos dos fármacos , Neutrófilos/metabolismo , Receptor 4 Toll-Like/metabolismo
19.
Sci Rep ; 9(1): 6884, 2019 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-31053741

RESUMO

Mast cells play a crucial role in allergic diseases via the release of inflammatory mediators, particularly histamine and pro-inflammatory cytokines. Avenanthramide (Avn) C, a polyphenol found mainly in oats, is known to exhibit various biological properties. In this study, we aimed to evaluate the effectiveness of Avn C from germinated oats against mast cell-mediated allergic inflammation. For the in vitro study, RBL-2H3, mouse bone marrow-derived mast cells and rat peritoneal mast cells were used. Avn C (1-100 nM) inhibited the immunoglobulin (Ig)E-stimulated mast cells degranulation by suppressing phosphorylation of phosphoinositide 3-kinase and phospholipase Cγ1 and decreasing intracellular calcium levels. It inhibited IgE-stimulated secretion of inflammatory cytokines via suppression of FcεRI-mediated signaling proteins Lyn, Syk, Akt, and nuclear factor-κB. To verify the effects of Avn C in vivo, ovalbumin-induced active systemic anaphylaxis (ASA) and IgE-mediated passive cutaneous anaphylaxis (PCA) models were used. Oral administration of Avn C dose-dependently attenuated the ASA reactions, as evidenced by the inhibition of hypothermia and reduction of elevated serum histamine, IgE, and interleukin-4 levels. Avn C also inhibited the PCA reactions, such as ear swelling and plasma extravasation. Our results suggested that Avn C from germinated oats might be a possible therapeutic candidate for mast cell-mediated allergic inflammation.


Assuntos
Antialérgicos/farmacologia , Anti-Inflamatórios/farmacologia , Avena/química , Avena/crescimento & desenvolvimento , Germinação , Mastócitos/efeitos dos fármacos , ortoaminobenzoatos/farmacologia , Animais , Degranulação Celular/efeitos dos fármacos , Citocinas/metabolismo , Masculino , Mastócitos/imunologia , Camundongos , Camundongos Endogâmicos ICR
20.
Cells ; 8(5)2019 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-31035320

RESUMO

Cholesterol is an essential structural component of cellular membranes. In addition to the structural role, it also serves as a precursor to a variety of steroid hormones and has diverse functions in intracellular signal transduction. As one of its functions in cell signaling, recent evidence suggests that cholesterol plays a key role in regulating angiogenesis. This review discusses the role of cholesterol in angiogenesis, with a particular emphasis on cholesterol trafficking in endothelial cell signaling. Small molecule inhibitors of cholesterol trafficking and their preclinical and clinical development targeting angiogenesis and cancer are also discussed.


Assuntos
Inibidores da Angiogênese/farmacologia , Colesterol/fisiologia , Células Endoteliais , Neoplasias , Neovascularização Patológica , Animais , Transporte Biológico/efeitos dos fármacos , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Células Endoteliais/citologia , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/patologia , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Neovascularização Patológica/tratamento farmacológico , Neovascularização Patológica/metabolismo , Transdução de Sinais/efeitos dos fármacos
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