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1.
Chemotherapy ; 2023 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-38071975

RESUMO

INTRODUCTION: Gastric cancer is the 5th most common cancer and 3rd leading cause of cancer-related death worldwide. There are three main ways to treat gastric cancer: surgical resection, radiation therapy, and drug therapy. Furthermore, combinations of two to three regimens can improve survival. However, the survival outcomes of chemotherapy in advanced gastric cancer patients are still unsatisfactory. Unfortunately, no widely useful biomarkers have been verified to predict the efficacy of chemotherapy for locally advanced gastric cancer. METHODS: An MTT assay was used to determine the cell viability after cisplatin or oxaliplatin treatment. Western blotting and immunohistochemistry were utilized to examine the sFRP4 level and associated signaling pathways. Immunofluorescence staining was utilized to analyze the location of ß-catenin. Colony formation and Transwell assays were used to analyze the functions related with cisplatin, oxaliplatin and sFRP4. RESULTS: We have found that gastric cancer patients treated with combinations of 5-fluorouracil (5-FU) and cisplatin regimens have better survival rates than those treated with 5-FU-based chemotherapy alone. Secreted frizzled-related protein 4 (sFRP4) was selected as a potential target from stringent analysis and intersection of 5-FU and cisplatin resistance-related gene sets. sFRP4 was shown to be overexpressed in clinical gastric tumor tissues and positively correlated with a worse survival rate. In addition, sFRP4 and ß-catenin were upregulated in cisplatin-resistant and oxaliplatin-resistant gastric cancer cells compared to parental cells. Immunofluorescence staining and nuclear fractionation showed that ß-catenin translocated from the cytosol into the nucleus. Moreover, sFRP4 was detected in the conditioned medium of these resistant cells, which indicates that sFRP4 might have an extracellular role in chemotherapy resistance. Increased migration capacity and dysregulation of epithelial-mesenchymal transition-related markers, which might result from the dysregulation of sFRP4, were observed in cisplatin-resistant and oxaliplatin-resistant gastric cancer cells. DISCUSSION/CONCLUSION: In summary, sFRP4 might play a critical role in resistance to cisplatin and oxaliplatin, cell metastasis and poor prognosis in gastric cancer via the Wnt-ß-catenin pathway. Investigations of the molecular mechanism underlying sFRP4-modulated cancer progression and chemotherapeutic outcomes can provide additional therapeutic strategies for gastric cancer.

2.
Curr Issues Mol Biol ; 45(10): 8138-8151, 2023 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-37886957

RESUMO

EGFR tyrosine kinase inhibitors (TKIs) are the first-line treatment for advanced EGFR-mutated non-small-cell lung cancer (NSCLC). However, NSCLC patients with wild-type EGFR and KRAS mutation are ineligible for EGFR-TKIs. Therefore, the discovery of new therapeutic agents is urgently needed for NSCLC patients who cannot receive targeted therapies. Natural products possess tremendous chemical diversity and have been extensively investigated for their anticancer activity. In this study, we found that Cucurbitacin E (Cu E), a triterpene of cucurbitacins widely presented in the edible plants of the Cucurbitaceae family, significantly inhibits the viability and proliferation of A549 cells that harbor wild-type EGFR and KRAS mutation. Our results revealed that Cu E increases cell-cycle arrest at G2/M and subG1 phase. Mechanistically, Cu E significantly inhibits the phosphorylation and protein levels of regulatory proteins and hinders G2/M cell-cycle progression. Meanwhile, the treatment of Cu E resulted in DNA damage response and apoptosis. For the first time, we observed that Cu E induces incomplete autophagy as evidenced by increased LC3B-II expression and p62-accumulation. Knockdown of p62 rescued the cells from Cu E-mediated anti-proliferative effect, apoptosis, DNA damage, and ROS production. These findings suggest that Cu E is a promising drug candidate for NSCLC.

3.
Int J Nanomedicine ; 18: 2647-2658, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37220630

RESUMO

Purpose: Morbid obesity and its related metabolic syndrome are an important health issue. Recently, sleeve gastrectomy (SG) and Roux-en-Y gastric bypass (RYGB) have accounted for the most popular bariatric surgeries. Valsartan (VST) is a common hypertension drug, and nano-carriers can increase its solubility and bioavailability. This study aims to explore the nano-VST formula in bariatric surgery subjects. Methods: High-fat fed animals were used as obese models. Operations were performed according to a standardized protocol. The drug was administrated by gavage, and blood samples were taken by serial tail vein sampling. Caco-2 cells were used for examining cell viability and drug uptake. A self-nano-emusifying drug delivery system (SNEDDS) formula was composed of sefsol-218, RH-40 and propylene glycol by a specified ratio, while high-performance liquid chromatography (HPLC) was used for determining drug concentrations. Results: Post-operatively, subjects that underwent RYGB lost more body weight compared to the SG group. The SNEDDS did not exhibit cytotoxicity after adequate dilution, and the cytotoxicity was not related to VST dose. A better cellular uptake of SNEDDS was observed in vitro. The SNEDDS formula achieved a diameter of 84 nm in distilled water and 140 nm in simulated gastric fluid. In obese animals, the maximum serum concentration (Cmax) of VST was increased 1.68-folds by SNEDDS. In RYGB with SUS, the Cmax was reduced to less than 50% of the obese group. SNEDDS increased the Cmax to 3.5 folds higher than SUS and resulted in 3.28-folds higher AUC0-24 in the RYGB group. Fluorescence imaging also confirmed a stronger signal of SNEDDS in the gastrointestinal mucosa. SNEDDS accumulated a higher drug concentration than suspension alone in the liver of the obese group. Conclusion: SNEDDS could reverse the VST malabsorption in RYGB. Further studies are mandatory to clarify post-SG change of drug absorption.


Assuntos
Cirurgia Bariátrica , Animais , Humanos , Preparações Farmacêuticas , Valsartana , Células CACO-2 , Sistemas de Liberação de Medicamentos , Obesidade
4.
Cardiovasc Diabetol ; 22(1): 57, 2023 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-36915157

RESUMO

BACKGROUND: Patients with type 2 diabetes are at increased risk for cardiovascular diseases. Sodium-glucose transport 2 inhibitors (SGLT2i) have been shown to enhance cardiovascular health since their debut as a second-line therapy for diabetes. Acute coronary syndrome (ACS), peripheral arterial occlusive disease (PAOD), and ischemic stroke (IS) are types of atherosclerotic cardiovascular disease (ASCVD), although the benefits of treating these disorders have not been shown consistently. METHODS: We searched four databases (PubMed, Embase, the Cochrane library, and clinicaltrial.gov) for randomized clinical trials (RCTs) until November of 2022. Comparisons were made between SGLT2i-treated and control individuals with type 2 diabetes. Primary outcomes were ACS, PAOD, and IS; secondary outcomes included cardiovascular mortality and all-cause mortality. Risk ratio (RR) and 95% confidence intervals (CI) were determined using a fixed effects model. Cochrane's risk-of-bias (RoB2) instrument was used to assess the validity of each study that met the inclusion criteria. RESULTS: We enrolled 79,504 patients with type 2 diabetes from 43 RCTs. There was no difference in the risk of ACS (RR = 0.97, 95% CI 0.89-1.05), PAOD (RR = 0.98, 95% CI 0.78-1.24), or IS (RR = 0.95, 95% CI 0.79-1.14) among patients who took an SGLT2i compared to those who took a placebo or oral hypoglycemic drugs. Subgroup analysis revealed that none of the SGLT2i treatments (canagliflozin, dapagliflozin, empagliflozin, and ertugliflozin) significantly altered outcomes when analyzed separately. Consistent with prior findings, SGLT2i reduced the risk of cardiovascular mortality (RR = 0.85, 95% CI 0.77-0.93) and all-cause mortality (RR = 0.88, 95% CI 0.82-0.94). CONCLUSION: Our results appear to contradict the mainstream concepts regarding the cardiovascular effects of SGLT2i since we found no significant therapeutic benefits in SGLT2i to reduce the incidence of ACS, PAOD, or IS when compared to placebo or oral hypoglycemic drugs.


Assuntos
Síndrome Coronariana Aguda , Diabetes Mellitus Tipo 2 , AVC Isquêmico , Inibidores do Transportador 2 de Sódio-Glicose , Humanos , Síndrome Coronariana Aguda/diagnóstico , Síndrome Coronariana Aguda/tratamento farmacológico , Síndrome Coronariana Aguda/complicações , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/complicações , Ensaios Clínicos Controlados Aleatórios como Assunto , Inibidores do Transportador 2 de Sódio-Glicose/efeitos adversos
5.
Mar Drugs ; 21(2)2023 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-36827114

RESUMO

Bladder cancer (BC) is one of the most prevalent cancers worldwide. However, the recurrence rate and five-year survival rate have not been significantly improved in advanced BC, and new therapeutic strategies are urgently needed. The anticancer activity of stellettin B (SP-2), a triterpene isolated from the marine sponge Rhabdastrella sp., was evaluated with the MTT assay as well as PI and Annexin V/7-AAD staining. Detailed mechanisms were elucidated through an NGS analysis, protein arrays, and Western blotting. SP-2 suppressed the viability of BC cells without severe toxicity towards normal uroepithelial cells, and it increased apoptosis with the activation of caspase 3/8/9, PARP, and γH2AX. The phosphorylation of FGFR3 and its downstream targets were downregulated by SP-2. Meanwhile, it induced autophagy in BC cells as evidenced by LC3-II formation and p62 downregulation. The inhibition of autophagy using pharmacological inhibitors or through an ATG5-knockout protected RT-112 cells from SP-2-induced cell viability suppression and apoptosis. In addition, the upregulation of DAPK2 mRNA and protein expression also contributed to SP-2-induced cytotoxicity and apoptosis. In RT-112 cells, an FGFR3-TACC3-knockout caused the downregulation of DAPK2, autophagy, and apoptosis. In conclusion, this is the first study demonstrating that SP-2 exhibits potent anti-BC activity by suppressing the FGFR3-TACC3/Akt/mTOR pathway, which further activates a novel autophagy/DAPK2/apoptosis signaling cascade.


Assuntos
Poríferos , Triterpenos , Neoplasias da Bexiga Urinária , Animais , Proteínas Quinases Associadas com Morte Celular , Apoptose , Triterpenos/farmacologia , Neoplasias da Bexiga Urinária/tratamento farmacológico , Autofagia , Poríferos/metabolismo , Linhagem Celular Tumoral , Proteínas Proto-Oncogênicas c-akt/metabolismo
6.
Cancers (Basel) ; 13(23)2021 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-34885226

RESUMO

Glioblastoma multiforme (GBM) is the most malignant brain tumor in the world, only 25% of GBM patients were alive one year after diagnosis. Although Temozolamide combined with radiation therapy more effectively prolonged the survival rate than radiation alone, the overall survival rate is still dismal. Therefore, a new therapeutic strategy is urgently needed. CDK4/6 inhibitors are newly FDA-approved agents to treat HR-positive, HER2-negative advanced, and metastatic breast cancers, and preclinical results showed that CDK4/6 inhibitors significantly reduced cell proliferation and tumor growth. However, several studies have suggested that CDK4/6 inhibitor-induced non-genetic changes caused treatment failure, including autophagy activation. Therefore, this study aimed to combine an autophagy inhibitor, MPT0L145, with abemaciclib to improve therapeutic efficiency. The use of abemaciclib effectively inhibited cell proliferation via suppression of RB phosphorylation and induced autophagy activation in GBM cancer cells. MPT0L145 treatment alone not only blocked autophagy activation, but also induced generation of ROS and DNA damage in a concentration-dependent manner. Importantly, MPT0L145 had a comparable penetration ability to TMZ in our blood brain barrier permeability assay. Combined MPT0L145 with abemaciclib significantly reduced cell proliferation, suppressed RB phosphorylation, and increased ROS production. In conclusion, the data suggested that blocking autophagy by MPT0L145 synergistically sensitized GBM cancer cells to abemaciclib and represents a potential therapeutic strategy for treating GBM in the future.

7.
Cancers (Basel) ; 12(12)2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-33271970

RESUMO

Pediatric ependymomas are a type of malignant brain tumor that occurs in children. The overall 10-year survival rate has been reported as being 45-75%. Maximal safe surgical resection combined with adjuvant chemoradiation therapy is associated with the highest overall and progression-free survival rates. Despite aggressive treatment, one-third of ependymomas exhibit recurrence within 2 years of initial treatment. Therefore, this study aimed to find new agents to overcome chemoresistance and defer radiotherapy treatment since, in addition, radiation exposure may cause long-term side effects in the developing brains of young children. By using integrated bioinformatics and through experimental validation, we found that at least one of the genes CCND1 and CDK4 is overexpressed in ependymomas. The use of abemaciclib, a highly selective CDK4/6 inhibitor, effectively inhibited cell proliferation and reduced the expression of cell-cycle-related and DNA-repair-related gene expression via the suppression of RB phosphorylation, which was determined through RNA-seq and Western blot analyses. Furthermore, abemaciclib effectively induced cell death in vitro. The efficiency of abemaciclib was validated in vivo using subcutaneously implanted ependymoma tissues from patient-derived xenografts (PDXs) in mouse models. Treatment with abemaciclib showed encouraging results in preclinical pediatric ependymoma models and represents a potential therapeutic strategy for treating challenging tumors in children.

8.
Plant Direct ; 4(9): e00266, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33015534

RESUMO

Small ubiquitin-like modifier (SUMO) conjugation, or SUMOylation, is a reversible post-translational modification that is important for regulation of many cellular processes including cell division cycle in the eukaryotic kingdom. However, only a portion of the components of the Chlamydomonas SUMOylation system are known and their functions and regulation investigated. The present studies are aimed at extending discovery and characterization of new components and improving the annotation and nomenclature of all known proteins and genes involved in the system. Even though only one copy of the heterodimerized SUMO-activating enzyme, SAE1 and SAE2, was identified, the number of SUMO-conjugating enzymes (SCEs) and SUMO proteases/isopeptidase was expanded in Chlamydomonas. Using the reconstituted SUMOylation system, we showed that SCE1, SCE2, and SCE3 have SUMO-conjugating activity. In addition to SUMOylation, components required for other post-translational modifications such as NEDDylation, URMylation, and UFMylation, were confirmed to be present in Chlamydomonas. Our data also showed that besides isopeptidase activity, the SUMO protease domain of SUPPRESSOR OF MAT3 7/SENTRIN-SPECIFIC PROTEASE 1 (SMT7/SENP1) has endopeptidase activity that is capable of processing SUMO precursors. Moreover, the key cell cycle regulators of Chlamydomonas E2F1, DP1, CDKG1, CYCD2, and CYCD3 were SUMOylated in vitro, suggesting SUMOylation may be part of regulatory pathway modulating cell cycle regulators.

11.
Aging (Albany NY) ; 12(7): 5764-5780, 2020 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-32282334

RESUMO

Bladder cancer is the second most common genitourinary malignancy in the world. However, only immune-checkpoint inhibitors and erdafitinib are available to treat advanced bladder cancer. Our previous study reported that 4-((4-(4-ethylpiperazin-1-yl) phenyl)amino)-N-(3,4,5-trichlorophenyl)-7H-pyrrolo-[2, 3-d]pyrimidine-7-carboxamide hydrochloride (13i HCl) is a potent CK1δ inhibitor showing significant anti-bladder cancer activity. In this study, we elucidated the pharmacological mechanisms underlying 13i HCl's inhibition of human bladder cancer. Our results demonstrate that expression of the CSNK1D gene, which codes for CK1δ, is upregulated in superficial and infiltrating bladder cancer patients in two independent datasets. CK1δ knockdown decreased ß-catenin expression in bladder cancer cells and inhibited their growth. Additionally, 13i HCl suppressed bladder cancer cell proliferation and increased apoptosis. We also observed that inhibition of CK1δ using 13i HCl or PF-670462 triggers necroptosis in bladder cancer cells. Finally, 13i HCl inhibited bladder cancer cell migration and reversed their mesenchymal characteristics. These findings suggest further development of 13i HCl as a potential therapeutic agent to treat bladder cancer is warranted.


Assuntos
Apoptose/efeitos dos fármacos , Caseína Quinase Idelta/metabolismo , Proliferação de Células/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Pirimidinas/farmacologia , Neoplasias da Bexiga Urinária/metabolismo , Caseína Quinase Idelta/antagonistas & inibidores , Caseína Quinase Idelta/genética , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Técnicas de Silenciamento de Genes , Humanos , Regulação para Cima/efeitos dos fármacos , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/patologia
13.
Eur J Med Chem ; 192: 112158, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32171161

RESUMO

Microtubule-targeting agents (MTA) have enjoyed significant clinical success for decades. However, several mechanisms may cause inactivation of such drugs, leading to acquired resistance in patients treated with them. Therefore, drugs containing a stilbene-like skeleton and possessing dual inhibitory activity may provide a new and differentiated treatment for patients to overcome challenging acquired resistance. A new compound (16c) displays promising anticancer activity with GI50 of 22 ± 2 and 12 ± 0.1 nM in vincristine-resistant nasopharyngeal (KB-Vin) cancer cells and etoposide-resistant nasopharyngeal (KB-7D) cancer cells and is better than vincristine, etoposide, ABT-751, and MS-275. A mechanistic study revealed that 16c interferes with the cell cycle distribution and induces cell cycle arrest at the G2/M phase and severe mitotic spindle defects followed by apoptosis. In addition, it produces much more significant cytotoxicity than vincristine and etoposide in the corresponding resistant cells, indicating that it may be a promising candidate to overcome drug resistance in cancer cells. Compound 16c also displays inhibitory activity against HDAC 1 and HDAC 2 with IC50 values of 1.07 µM, and 1.47 µM, respectively. These findings may lead to a new type of structural motif for future development of drugs that could overcome acquired resistance to MTAs.


Assuntos
Antineoplásicos/farmacologia , Benzamidas/farmacologia , Desenho de Fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Inibidores de Histona Desacetilases/farmacologia , Histona Desacetilases/metabolismo , Microtúbulos/efeitos dos fármacos , Antineoplásicos/síntese química , Antineoplásicos/química , Benzamidas/síntese química , Benzamidas/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Inibidores de Histona Desacetilases/síntese química , Inibidores de Histona Desacetilases/química , Humanos , Isoenzimas/antagonistas & inibidores , Isoenzimas/metabolismo , Estrutura Molecular , Relação Estrutura-Atividade , Vincristina/farmacologia
14.
Polymers (Basel) ; 12(2)2020 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-32050563

RESUMO

We developed a new format for liquid crystal (LC)-based multi-microfluidic immunoassays, hosted on a polydimethylsiloxane substrate. In this design, the orientations of the LCs were strongly affected by the interface between the four microchannel walls and surrounding LCs. When the alignment layer was coated inside a microchannel, the LCs oriented homeotropically and appeared dark under crossed polarizers. After antigens bound to the immobilized antibodies on the alignment layer were coated onto the channel walls, the light intensity of the LC molecules changed from dark to bright because of disruption of the LCs. By employing pressure-driven flow, binding of the antigen/antibody could be detected by optical signals in a sequential order. The multi-microfluidic LC biosensor was tested by detecting bovine serum albumin (BSA) and an immunocomplex of BSA antigen/antibody pairs, a protein standard commonly used in labs. We show that this multi-microfluidic immunoassay was able to detect BSA and antigen/antibody BSA pairs with a naked-eye detection limitation of -0.01 µg/mL. Based on this new immunoassay design, a simple and robust device for LC-based label-free microfluidic immunodetection was demonstrated.

15.
Eur J Med Chem ; 190: 112086, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-32058238

RESUMO

This study reports the synthesis of a series of 2-aroylisoindoline hydroxamic acids employing N-benzyl, long alkyl chain and acrylamide units as diverse linkers. In-vitro studies led to the identification of N-benzyl linker-bearing compound (10) and long chain linker-containing compound (17) as dual selective HDAC6/HSP90 inhibitors. Compound 17 displays potent inhibition of HDAC6 isoform (IC50 = 4.3 nM) and HSP90a inhibition (IC50 = 46.8 nM) along with substantial cell growth inhibitory effects with GI50 = 0.76 µM (lung A549) and GI50 = 0.52 µM (lung EGFR resistant H1975). Compound 10 displays potent antiproliferative activity against lung A549 (GI50 = 0.37 µM) and lung H1975 cell lines (GI50 = 0.13 µM) mediated through selective HDAC6 inhibition (IC50 = 33.3 nM) and HSP90 inhibition (IC50 = 66 nM). In addition, compound 17 also modulated the expression of signatory biomarkers associated with HDAC6 and HSP90 inhibition. In the in vivo efficacy evaluation in human H1975 xenografts, 17 induced slightly remarkable suppression of tumor growth both in monotherapy as well as the combination therapy with afatinib (20 mg/kg). Moreover, compound 17 could effectively reduce programmed death-ligand 1 (PD-L1) expression in IFN-γ treated lung H1975 cells in a dose dependent manner suggesting that dual inhibition of HDAC6 and HSP90 can modulate immunosuppressive ability of tumor area.


Assuntos
Antineoplásicos/uso terapêutico , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Inibidores de Histona Desacetilases/uso terapêutico , Ácidos Hidroxâmicos/uso terapêutico , Isoindóis/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Animais , Antineoplásicos/síntese química , Antineoplásicos/metabolismo , Apoptose/efeitos dos fármacos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Domínio Catalítico , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Proteínas de Choque Térmico HSP90/química , Proteínas de Choque Térmico HSP90/metabolismo , Desacetilase 6 de Histona/química , Desacetilase 6 de Histona/metabolismo , Inibidores de Histona Desacetilases/síntese química , Inibidores de Histona Desacetilases/metabolismo , Humanos , Ácidos Hidroxâmicos/síntese química , Ácidos Hidroxâmicos/metabolismo , Isoindóis/síntese química , Isoindóis/metabolismo , Masculino , Camundongos Endogâmicos BALB C , Simulação de Acoplamento Molecular , Ligação Proteica , Ensaios Antitumorais Modelo de Xenoenxerto
16.
Plant Cell ; 32(4): 1285-1307, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32060174

RESUMO

Proliferating cells actively coordinate growth and cell division to ensure cell-size homeostasis; however, the underlying mechanism through which size is controlled is poorly understood. Defect in a SUMO protease protein, suppressor of mat3 7 (SMT7), has been shown to reduce cell division number and increase cell size of the small-size mutant mating type locus 3-4 (mat3-4), which contains a defective retinoblastoma tumor suppressor-related protein of Chlamydomonas (Chlamydomonas reinhardtii). Here we describe development of an in vitro SUMOylation system using Chlamydomonas components and use it to provide evidence that SMT7 is a bona fide SUMO protease. We further demonstrate that the SUMO protease activity is required for supernumerous mitotic divisions of the mat3-4 cells. In addition, we identified RIBOSOMAL PROTEIN L30 (RPL30) as a prime SMT7 target and demonstrated that its SUMOylation is an important modulator of cell division in mat3-4 cells. Loss of SMT7 caused elevated SUMOylated RPL30 levels. Importantly, overexpression of the translational fusion version of RPL30-SUMO4, which mimics elevation of the SUMOylated RPL30 protein in mat3-4, caused a decrease in mitotic division and recapitulated the size-increasing phenotype of the smt7-1 mat3-4 cells. In summary, our study reveals a novel mechanism through which a SUMO protease regulates cell division in the mat3-4 mutant of Chlamydomonas and provides yet another important example of the role that protein SUMOylation can play in regulating key cellular processes, including cell division.


Assuntos
Pontos de Checagem do Ciclo Celular , Chlamydomonas reinhardtii/citologia , Chlamydomonas reinhardtii/metabolismo , Proteínas de Plantas/metabolismo , Proteínas Ribossômicas/metabolismo , Proteínas Modificadoras Pequenas Relacionadas à Ubiquitina/metabolismo , Sequência de Aminoácidos , Pontos de Checagem do Ciclo Celular/genética , Tamanho Celular , Ritmo Circadiano/genética , Regulação da Expressão Gênica de Plantas , Mutação/genética , Membrana Nuclear/metabolismo , Fenótipo , Proteínas de Plantas/química , Proteínas de Plantas/genética , Antígeno Nuclear de Célula em Proliferação/metabolismo , Ligação Proteica , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas Modificadoras Pequenas Relacionadas à Ubiquitina/química , Sumoilação
17.
Eur J Med Chem ; 185: 111725, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31655430

RESUMO

Novel dual inhibitors of histone deacetylase (HDAC) and heat-shock protein 90 (HSP90) are synthesized and evaluated. These compounds are endowed with potent HDAC and HSP90 inhibitory activities with IC50 values in nanomolar range with Compound 20 (HDAC IC50 = 194 nM; HSP90α IC50 = 153 nM) and compound 26 (HDAC IC50 = 360 nM; HSP90α IC50 = 77 nM) displaying most potent HDAC and HSP90α inhibitory activities. Both of these compounds induce HSP70 expression and down regulate HSP90 client proteins which play important roles in the regulation of survival and invasiveness in cancer cells. In addition, compounds 20 and 26 induce acetylation of α-tubulin and histone H3. Significantly, compounds 20 and 26 could effectively reduce programmed death-ligand 1 (PD-L1) expression in IFN-γ treated lung H1975 cells in a dose dependent manner. These findings suggest that dual inhibition of HDAC and HSP90 that can modulate immunosuppressive ability of tumor area may provide a better therapeutic strategy for cancer treatment in the future.


Assuntos
Anilidas/farmacologia , Antineoplásicos/farmacologia , Inibidores Enzimáticos/farmacologia , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Histona Desacetilases/metabolismo , Ácidos Hidroxâmicos/farmacologia , Anilidas/síntese química , Anilidas/química , Antineoplásicos/síntese química , Antineoplásicos/química , Antígeno B7-H1/antagonistas & inibidores , Antígeno B7-H1/biossíntese , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Regulação para Baixo/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Proteínas de Choque Térmico HSP90/metabolismo , Humanos , Ácidos Hidroxâmicos/síntese química , Ácidos Hidroxâmicos/química , Interferon gama/antagonistas & inibidores , Interferon gama/biossíntese , Estrutura Molecular , Relação Estrutura-Atividade , Células Tumorais Cultivadas
19.
Cancers (Basel) ; 11(10)2019 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-31652644

RESUMO

Colorectal cancer (CRC) is the third most common cancer and the leading cause of cancer-associated death worldwide. Histone deacetylases (HDACs) have been implicated in regulating complex cellular mechanisms to influence tumor biology and immunogenicity in various types of cancer. The potential of selective inhibition of HDAC6 has been widely discussed for the treatment of hematologic malignancies. We previously identified that MPT0G612 is a novel HDAC6 inhibitor exhibiting a promising antitumor activity against several solid tumors. The purpose of the present study was to evaluate the feasibility and pharmacological mechanisms of MPT0G612 as a potential therapy for CRC patients. Results revealed that MPT0G612 significantly suppresses the proliferation and viability, as well as induces apoptosis in CRC cells. Autophagy activation with LC3B-II formation and p62 degradation was observed, and the inhibition of autophagy by pharmacological inhibitor or Atg5 knockdown enhances MPT0G612-induced cell death. In addition, HDAC6 knockdown reduces MPT0G612-mediated autophagy and further potentiates apoptotic cell death. Furthermore, MPT0G612 downregulates the expression of PD-L1 induced by IFN-γ in CRC cells. These results suggest that MPT0G612 is a potent cell death inducer through inhibiting HDAC6-associated pathway, and a potential agent for combination strategy with immune checkpoint inhibitors for the treatment of CRC.

20.
Cancers (Basel) ; 11(9)2019 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-31514441

RESUMO

Anticancer therapies reportedly promote pro-survival autophagy in cancer cells that confers drug resistance, rationalizing the concept to combine autophagy inhibitors to increase their therapeutic potential. We previously identified that MPT0L145 is a PIK3C3/FGFR inhibitor that not only increases autophagosome formation due to fibroblast growth factor receptor (FGFR) inhibition but also perturbs autophagic flux via PIK3C3 inhibition in bladder cancer cells harboring FGFR activation. In this study, we hypothesized that combined-use of MPT0L145 with agents that induce pro-survival autophagy may provide synthetic lethality in cancer cells without FGFR activation. The results showed that MPT0L145 synergistically sensitizes anticancer effects of gefitinib and gemcitabine in non-small cell lung cancer A549 cells and pancreatic cancer PANC-1 cells, respectively. Mechanistically, drug combination increased incomplete autophagy due to impaired PIK3C3 function by MPT0L145 as evidenced by p62 accumulation and no additional apoptotic cell death was observed. Meanwhile, drug combination perturbed survival pathways and increased vacuolization and ROS production in cancer cells. In conclusion, the data suggest that halting pro-survival autophagy by targeting PIK3C3 with MPT0L145 significantly sensitizes cancer cells to targeted or chemotherapeutic agents, fostering rational combination strategies for cancer therapy in the future.

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