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1.
Bioengineering (Basel) ; 10(8)2023 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-37627846

RESUMO

SARS-CoV-2 exploits the homotrimer transmembrane Spike glycoproteins (S protein) during host cell invasion. The Omicron XBB subvariant, delta, and prototype SARS-CoV-2 receptor-binding domain show similar binding strength to hACE2 (human Angiotensin-Converting Enzyme 2). Here we utilized multiligand virtual screening to identify small molecule inhibitors for their efficacy against SARS-CoV-2 virus using QPLD, pseudovirus ACE2 Inhibition -Time Resolved Forster/Fluorescence energy transfer (TR-FRET) Assay Screening, and Molecular Dynamics simulations (MDS). Three hundred and fifty thousand compounds were screened against the macrodomain of the nonstructural protein 3 of SARS-CoV-2. Using TR-FRET Assay, we filtered out two of 10 compounds that had no reported activity in in vitro screen against Spike S1: ACE2 binding assay. The percentage inhibition at 30 µM was found to be 79% for "Compound F1877-0839" and 69% for "Compound F0470-0003". This first of its kind study identified "FILLY" pocket in macrodomains. Our 200 ns MDS revealed stable binding poses of both leads. They can be used for further development of preclinical candidates.

2.
Viruses ; 15(2)2023 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-36851795

RESUMO

The current outbreak of coronavirus disease 2019 (COVID-19) has prompted the necessity of efficient treatment strategies. The COVID-19 pandemic was caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Main protease (Mpro), also called 3-chymotrypsin-like protease (3CL protease), plays an essential role in cleaving virus polyproteins for the functional replication complex. Therefore, Mpro is a promising drug target for COVID-19 therapy. Through molecular modelling, docking and a protease activity assay, we found four novel inhibitors targeting Mpro with the half maximal inhibitory concentration (IC50) and their binding affinities shown by the dissociation constants (KDs). Our new inhibitors CB-21, CB-25, CP-1 and LC24-20 have IC50s at 14.88 µM (95% Confidence Interval (95% CI): 10.35 µM to 20.48 µM), 22.74 µM (95% CI: 13.01 µM to 38.16 µM), 18.54µM (95% CI: 6.54 µM to 36.30 µM) and 32.87µM (95% CI: 18.37 µM to 54.80 µM)), respectively. The evaluation of interactions suggested that each inhibitor has a hydrogen bond or hydrophobic interactions with important residues, including the most essential catalytic residues: His41 and Cys145. All the four inhibitors have a much higher 50% lethal dose (LD50) compared with the well-known Mpro inhibitor GC376, demonstrating its low toxicity. These four inhibitors can be potential drug candidates for further in vitro and in vivo studies against COVID-19.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Pandemias , Antivirais/farmacologia , Peptídeo Hidrolases
3.
J Steroid Biochem Mol Biol ; 228: 106246, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36634828

RESUMO

Human type 1 17ß-hydroxysteroid dehydrogenase (17ß-HSD1),a member of the short-chain dehydrogenase/reductase family, catalyzes the last step in the bioactivation of the most potent estrogen estradiol with high specificity and is thus involved in estrogen-dependent diseases. As an oxidoreductase, 17ß-HSD1 can utilize both triphosphate and diphosphate cofactors in reaction at the molecular level, but more specific with triphosphate cofactor. The NADPH is much higher than NADP+ in living cells leading to preliminary reduction action. The enzyme also showed substrate-induced inhibition unprecedented in other members of 17ß-HSDs. Our previous study elucidated the structural mechanism of substrate inhibition is due to the reversely bound estrone (E1) in the substrate-binding pocket of the enzyme resulting in a dead-end complex. However, the effect of the cofactor preference on the substrate inhibition of the enzyme is not yet clear. In the present study, we solved the ternary crystal structures of 17ß-HSD1 in complex with E1 and cofactor analog NAD+ . Combined with molecular dynamics simulation using the enzyme with NADH/NADPH and different oriented E1 (normally oriented, E1N; reversely oriented, E1R), such ternary structure provides a complete picture of enzyme-substrate-cofactor interactions. The results reveal that different cofactors and substrate binding mode affect the allosteric effect between the two subunits of the enzyme. And the results from MD simulations confirmed that His221 plays a key role in the formation of dead-end complex in NADPH complex, and the absence of stable interaction between His221 and E1R in the NADH complex should be the main reason for its lack of substrate inhibition.


Assuntos
17-Hidroxiesteroide Desidrogenases , NAD , Humanos , 17-Hidroxiesteroide Desidrogenases/metabolismo , Sítios de Ligação , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/química , Estrogênios , NAD/metabolismo , NADP/metabolismo , Ligação Proteica , Especificidade por Substrato
4.
Cancers (Basel) ; 14(4)2022 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-35205737

RESUMO

Paclitaxel (taxol), a chemotherapeutic agent, remains the standard of care for the lethal triple-negative breast cancer (TNBC). However, over 50% of TNBC patients become resistant to chemotherapy and, to date, no solution is available. CR6-interacting factor 1 (CRIF1) is reported to act as a negative regulator of the cell cycle by interacting with cyclin-dependent kinase 2 (CDK2). In our study, two selective CRIF1-CDK2 interface inhibitors were used to investigate whether they could exert anti-proliferative activity on the TNBC cell lines. When combined with taxol treatment, these two inhibitors can advance the cells from G0/G1 to S and G2/M phases, producing irreparable damage to the cells, which then undergo apoptosis. Moreover, they enhanced the reduction in cell proliferation induced by taxol in TNBC cells, thereby improving sensitivity to taxol in these cell lines. Importantly, the inhibitors did not regulate the cell cycle in normal cells, indicating their high selectivity towards TNBC cells. Overall, the resistance to the anti-proliferative effects induced by taxol can be significantly reduced by the combined treatment with selective CRIF1-CDK2 interface inhibitors, making a conceptual advance in the CDK-related cancer treatment.

5.
Am J Cancer Res ; 11(11): 5358-5373, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34873465

RESUMO

Epithelial ovarian cancer, widely suggested as endocrine-related cancer, yields a low survival rate among patients. Despite intensive research for nearly a century, there have been no fundamental advances in treatment. The reductive 17ß-HSD7 is a special enzyme possessing a remarkable dual activity in both the biosynthesis of the most potent estrogen estradiol and the inactivation of the most active androgen dihydrotestosterone. In the present study, we observed over-expression of 17ß-HSD7 in EOC cells such as OVCAR-3 and SKOV-3, in agreement with integrative data analysis demonstrating overexpression of 17ß-HSD7 in EOC tissues. After knocking down 17ß-HSD7, SKOV-3 cell proliferation decreased by 29%, cell arrest in the G2/M phase increased by 25% with cyclin B1/Cdk1 inhibition. Inhibition of 17ß-HSD7 in EOC cells triggered negative feedback of its expression, which further decreased the estradiol level to more than 60% under the experimental condition. Such inhibition increased the dihydrotestosterone level to many times higher and suppressed cell proliferation. Thus, 17ß-HSD7 is demonstrated to be a promising target for the endeavor against the malignant ovarian cancer, a menace in human life. The targeting of such an enzyme thus provides exceptional scientific importance.

6.
J Steroid Biochem Mol Biol ; 214: 105963, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34400276

RESUMO

Human 17ß-hydroxysteroid dehydrogenase type 7 (17ß-HSD7), a special multifunctional enzyme, activates the estrogen estrone while inactivating the potent androgen dihydrotestosterone. Thus, this enzyme has become an ideal target for hormone-dependent breast cancer treatment, as its inhibition leads to estradiol reduction and dihydrotestosterone restoration. However, a particular concern has arisen related to an additional role in cholesterol biosynthesis, as inhibition of the enzyme may lead to undesirable side effects. Our findings demonstrate that the available enzyme inhibitors are non-competitive. Among these, many such as INH81, are specific toward sex-hormone conversion, whereas others represented by 4-bromo-ethynylestradiol, are more specific for zymosterone reduction occurring during cholesterol biosynthesis. The binding of non-competitive inhibitors does not affect the substrate binding on the enzyme. This is the first demonstration of non-competitive inhibitors acting selectively on different catalyses, thereby facilitating inhibitor uses for breast cancer treatment. We aim to quickly communicate the novel results.


Assuntos
Neoplasias da Mama/tratamento farmacológico , 17-Hidroxiesteroide Desidrogenases/metabolismo , Sítio Alostérico , Androgênios/metabolismo , Neoplasias da Mama/metabolismo , Catálise , Colesterol/metabolismo , Di-Hidrotestosterona/metabolismo , Ensaios de Seleção de Medicamentos Antitumorais , Inibidores Enzimáticos/farmacologia , Estradiol/metabolismo , Estrogênios/metabolismo , Estrona/metabolismo , Feminino , Humanos , Cinética , Ligantes , Ligação Proteica , Análise de Regressão
7.
Biomed Pharmacother ; 137: 111232, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33486202

RESUMO

The global spread of COVID-19 constitutes the most dangerous pandemic to emerge during the last one hundred years. About seventy-nine million infections and more than 1.7 million death have been reported to date, along with destruction of the global economy. With the uncertainty evolved by alarming level of genome mutations, coupled with likelihood of generating only a short lived immune response by the vaccine injections, the identification of antiviral drugs for direct therapy is the need of the hour. Strategies to inhibit virus infection and replication focus on targets such as the spike protein and non-structural proteins including the highly conserved RNA-dependent-RNA-polymerase, nucleotidyl-transferases, main protease and papain-like proteases. There is also an indirect option to target the host cell recognition systems such as angiotensin-converting enzyme 2 (ACE2), transmembrane protease, serine 2, host cell expressed CD147, and the host furin. A drug search strategy consensus in tandem with analysis of currently available information is extremely important for the rapid identification of anti-viral. An unprecedented display of cooperation among the scientific community regarding SARS-CoV-2 research has resulted in the accumulation of an enormous amount of literature that requires curation. Drug repurposing and drug combinations have drawn tremendous attention for rapid therapeutic application, while high throughput screening and virtual searches support de novo drug identification. Here, we examine how certain approved drugs targeting different viruses can play a role in combating this new virus and analyze how they demonstrate efficacy under clinical assessment. Suggestions on repurposing and de novo strategies are proposed to facilitate the fight against the COVID-19 pandemic.


Assuntos
Antivirais/farmacologia , Tratamento Farmacológico da COVID-19 , COVID-19 , SARS-CoV-2 , COVID-19/epidemiologia , Desenvolvimento de Medicamentos/métodos , Reposicionamento de Medicamentos/métodos , Humanos , SARS-CoV-2/efeitos dos fármacos , SARS-CoV-2/fisiologia , Resultado do Tratamento , Proteínas Virais/antagonistas & inibidores , Proteínas Virais/genética , Internalização do Vírus/efeitos dos fármacos
8.
Sci Rep ; 10(1): 13990, 2020 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-32814785

RESUMO

Optical memory based on the electromagnetically induced transparency (EIT) in a double-[Formula: see text] atomic system provides a convenient way to convert the frequency, bandwidth or polarization of an optical pulse by storing it in one [Formula: see text] channel and retrieving it from another. This memory-based optical converter can be used to bridge the quantum nodes which have different physical properties in a quantum network. However, in real atoms, each energy level usually contains degenerate Zeeman states, which may lead to additional energy loss, as has been discussed in our recent theoretical paper (Tsai et al. in Phys. Rev. A 100, 063843). Here, we present an experimental study on the efficiency variation in the EIT-memory-based optical polarization conversion in cold cesium atoms under Zeeman-state optical pumping. The experimental results support the theoretical predictions. Our study provides quantitative knowledge and physical insight useful for practical implementation of an EIT-memory-based optical converter.

10.
J Phys Chem Lett ; 11(11): 4430-4435, 2020 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-32392072

RESUMO

The pandemic outbreak of a new coronavirus (CoV), SARS-CoV-2, has captured the world's attention, demonstrating that CoVs represent a continuous global threat. As this is a highly contagious virus, it is imperative to understand RNA-dependent-RNA-polymerase (RdRp), the key component in virus replication. Although the SARS-CoV-2 genome shares 80% sequence identity with severe acute respiratory syndrome SARS-CoV, their RdRps and nucleotidyl-transferases (NiRAN) share 98.1% and 93.2% identity, respectively. Sequence alignment of six coronaviruses demonstrated higher identity among their RdRps (60.9%-98.1%) and lower identity among their Spike proteins (27%-77%). Thus, a 3D structural model of RdRp, NiRAN, non-structural protein 7 (nsp7), and nsp8 of SARS-CoV-2 was generated by modeling starting from the SARS counterpart structures. Furthermore, we demonstrate the binding poses of three viral RdRp inhibitors (Galidesivir, Favipiravir, and Penciclovir), which were recently reported to have clinical significance for SARS-CoV-2. The network of interactions established by these drug molecules affirms their efficacy to inhibit viral RNA replication and provides an insight into their structure-based rational optimization for SARS-CoV-2 inhibition.


Assuntos
Betacoronavirus/enzimologia , Nucleotidiltransferases/química , RNA Polimerase Dependente de RNA/química , Adenina/análogos & derivados , Adenina/química , Adenina/metabolismo , Adenosina/análogos & derivados , Amidas/química , Amidas/metabolismo , Antivirais/química , Antivirais/metabolismo , Betacoronavirus/isolamento & purificação , Sítios de Ligação , COVID-19 , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/patologia , Infecções por Coronavirus/virologia , Humanos , Simulação de Acoplamento Molecular , Nucleotidiltransferases/metabolismo , Pandemias , Pneumonia Viral/epidemiologia , Pneumonia Viral/patologia , Pneumonia Viral/virologia , Estrutura Terciária de Proteína , Pirazinas/química , Pirazinas/metabolismo , Pirrolidinas/química , Pirrolidinas/metabolismo , RNA Polimerase Dependente de RNA/metabolismo , SARS-CoV-2
11.
J Steroid Biochem Mol Biol ; 196: 105494, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31610224

RESUMO

In spite of the significant progress of estrogen-dependent breast cancer (BC) treatment, aromatase inhibitor resistance is a major problem limiting the clinical benefit of this frontier endocrine-therapy. The aim of this study was to determine the differential expression of steroid-converting enzymes between tumor and adjacent normal tissues, as well as their correlation in modulating intratumoral steroid-hormone levels in post-menopausal estrogen-dependent BC. RNA sequencing dataset (n = 1097) of The-Cancer-Genome-Atlas (Breast Invasive Carcinoma) retrieved through the data portal of Genomic Data Commons was used for differential expressions and expression correlation analyses by Mann-Whitney U and Spearman's rank test, respectively. The results showed significant up-regulation of 17ß-HSD7 (2.50-fold, p < 0.0001) in BC, supporting its effect in sex-hormone control. Besides, suppression of 11ß-HSD1 expression (-8.29-fold, p < 0.0001) and elevation of 11ß-HSD2 expression (2.04-fold, p < 0.0001) provide a low glucocorticoid environment diminishing BC anti-proliferation. Furthermore, 3α-HSDs were down-regulated (-1.59-fold, p < 0.01; -8.18-fold, p < 0.0001; -33.96-fold, p < 0.0001; -31.85-fold, p < 0.0001 for type 1-4, respectively), while 5α-reductases were up-regulated (1.41-fold, p < 0.0001; 2.85-fold, p < 0.0001; 1.70-fold, p < 0.0001 for type 1-3, respectively) in BC, reducing cell proliferation suppressers 4-pregnenes, increasing cell proliferation stimulators 5α-pregnanes. Expression analysis indicates significant correlations between 11ß-HSD1 with 3α-HSD4 (r = 0.605, p < 0.0001) and 3α-HSD3 (r = 0.537, p < 0.0001). Significant expression correlations between 3α-HSDs were also observed. Our results systematically present the regulation of steroid-converting enzymes and their roles in modulating the intratumoral steroid-hormone levels in BC with a vivid 3D-schema, supporting novel therapy targeting the reductive 17ß-HSD7 and proposing a new combined therapy targeting 11ß-HSD2 and 17ß-HSD7.


Assuntos
Neoplasias da Mama/genética , Carcinoma Ductal de Mama/genética , Sistema Enzimático do Citocromo P-450/genética , Hormônios Esteroides Gonadais/genética , Receptores Citoplasmáticos e Nucleares/genética , 17-Hidroxiesteroide Desidrogenases/genética , 17-Hidroxiesteroide Desidrogenases/metabolismo , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/metabolismo , Carcinoma Ductal de Mama/epidemiologia , Carcinoma Ductal de Mama/metabolismo , Estudos de Coortes , Sistema Enzimático do Citocromo P-450/metabolismo , Bases de Dados Factuais/estatística & dados numéricos , Estradiol/farmacologia , Feminino , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Hormônios Esteroides Gonadais/metabolismo , Humanos , Setor Público/estatística & dados numéricos , Receptores Citoplasmáticos e Nucleares/metabolismo
12.
J Steroid Biochem Mol Biol ; 198: 105559, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31783154

RESUMO

Androgen receptor (AR) signaling is essential for prostate cancer (PC) progression and treatment. Experiments have demonstrated that the intratumoral androgen levels are not affected by circulating androgen levels, but rather modulated by local steroid-converting enzyme activities. The expression modulation status of human steroid-converting enzymes and nuclear receptors are of great promise to identify novel therapeutic targets. Meta-analysis was performed with 9 cohorts (1093 specimens) from Gene Expression Omnibus, 16 cohorts (933 specimens) from Oncomine and the TCGA cohort (550 specimens). We found significant up regulation of 5α-reductase type 1 and type 3 in both primary and metastatic PC, together with the down regulation of AKR1C2 in primary PC, contributing to the high intratumoral DHT levels. The expression of AR in metastatic PC was up regulated, indicating the importance of AR signaling in the progression of this cancer. The down regulations of HSD11B1 and NR3C1 in primary and metastatic PC may diminish the anti-inflammation and anti-proliferation effects of glucocorticoids signaling. Furthermore, the decrease of progesterone receptor (PGR) expression in primary and metastatic PC was also observed, relieving the suppression effect of PGR on PC proliferation. The clinical evidences of the remarkable expression modulation of steroid-converting enzymes and receptors in PC may indicate novel combined treatment against this highly incident cancer.


Assuntos
Regulação Neoplásica da Expressão Gênica , Neoplasias da Próstata/genética , 11-beta-Hidroxiesteroide Desidrogenase Tipo 1/genética , 3-Oxo-5-alfa-Esteroide 4-Desidrogenase/genética , Regulação para Baixo , Humanos , Hidroxiesteroide Desidrogenases/genética , Masculino , Neoplasias da Próstata/enzimologia , Neoplasias da Próstata/patologia , Receptores Androgênicos/genética , Receptores de Glucocorticoides/genética , Receptores de Progesterona/genética , Regulação para Cima
13.
J Cell Biochem ; 121(4): 2756-2769, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31693255

RESUMO

Breast cancer (BC) and prostate cancer (PC) are the second most common malignant tumors in women and men in western countries, respectively. The risks of death are 14% for BC and 9% for PC. Abnormal estrogen and androgen levels are related to carcinogenesis of the breast and prostate. Estradiol stimulates cancer development in BC. The effect of estrogen on PC is concentration-dependent, and estrogen can regulate androgen production, further affecting PC. Estrogen can also increase the risk of androgen-induced PC. Androgen has dual effects on BC via different metabolic pathways, and the role of the androgen receptor (AR) in BC also depends on cell subtype and downstream target genes. Androgen and AR can stimulate both primary PC and castration-resistant PC. Understanding the mechanisms of the effects of estrogen and androgen on BC and PC may help us to improve curative BC and PC treatment strategies.


Assuntos
Androgênios/metabolismo , Neoplasias da Mama/metabolismo , Estrogênios/metabolismo , Neoplasias da Próstata/metabolismo , Animais , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Estradiol , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Masculino , Fosforilação , Receptores Androgênicos/metabolismo , Receptores de Estrogênio/metabolismo , Risco , Transdução de Sinais
14.
J Steroid Biochem Mol Biol ; 195: 105471, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31513846

RESUMO

Breast cancer is a major cause of cancer-related death for women in western countries. 17ß-Hydroxysteroid dehydrogenases (17ß-HSDs) play important roles in the last step of sex-hormone activation and the first step of sex-hormone inactivation. 17ß-HSD2 is responsible for oxidizing the sex hormones. We used microarray technology to analyze the effect of 17ß-HSD2 on the MCF-7 cell transcript profile after knocking down 17ß-HSD2. Five hundred forty-two genes were regulated 1.5-fold or higher after treatment with 17ß-HSD2 siRNA. Knocking down 17ß-HSD2 interrupted nucleosome assembly. Pathway-Act-Network analysis showed that the MAPK and apoptosis signaling pathways were most regulated. In the gene-gene interaction network analysis, UGT2B15, which is involved in hormone metabolism, was the most regulated core gene. FOS, GREB1, and CXCL12 were the most regulated genes, and CXCL12 was related to tumor migration. Following 17ß-HSD2 knock-down, the cell viability decreased to 75.9%. The S-phase percentage decreased by 19.4%, the Q2-phase percentage in cell apoptosis testing increased by 1.5 times, and cell migration decreased to 66.0%. These results were consistent with our gene chip analysis and indicated that 17ß-HSD2 plays both hormone-dependent and hormone-independent enzymatic roles. In-depth investigations of this enzyme on the genomic level will help clarify its related molecular mechanisms.


Assuntos
Neoplasias da Mama/genética , Estradiol Desidrogenases/genética , Transcriptoma , Apoptose , Ciclo Celular , Humanos , Células MCF-7 , Análise de Sequência com Séries de Oligonucleotídeos , RNA Interferente Pequeno/genética
15.
J Steroid Biochem Mol Biol ; 193: 105411, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31207361

RESUMO

Reductive 17ß-hydroxysteroid dehydrogenases (17ß-HSDs) and 11ß-hydroxysteroid dehydrogenase 2 (11ß-HSD2) play crucial roles in respectively regulating steroids and glucocorticoids for the progression of hormone-dependent breast cancer. Most studies focused on the function and individual regulation of these enzymes. However, mutual regulation of these enzymes and the induced modulation on the estrogen and androgen receptors for breast cancer promotion are not yet clear. In this study, MCF-7 and T47D cells were treated with inhibitors of 17ß-HSD1, 17ß-HSD7, aromatase or steroid sulfatase (STS), then mRNA levels of 17ß-HSD7, STS, 11ß-HSD 2, estrogen receptors α (ERα) and androgen receptor (AR) were determined by Q-PCR. ER negative cell line MDA-MB-231 was used as a negative control. Our results demonstrate that 17ß-HSD7, STS and 11ß-HSD2 are all regulated by the same estrogen estradiol via ERα. When the gene of ERα (ESR1) was knocked down, there was no longer significant mutual regulation of these enzymes. Our results demonstrate that important steroidogenic enzymes transcriptionally regulated by ERα, can be mutually closely correlated. Inhibition of one of them can reduce the expression of another, thereby amplifying the role of the inhibition. Furthermore, inhibition of 17ß-HSD7 increases the expression of AR gene which is considered as a marker for better prognosis in ER + breast cancer, while maintaining ERα level. Thus, our mechanistic finding provides a base for further improving the endocrine therapy of ER + breast cancer, e.g., for selecting the target steroid enzymes, and for the combined targeting of human 17ß-HSD7 and ERα.


Assuntos
17-Hidroxiesteroide Desidrogenases/antagonistas & inibidores , Neoplasias da Mama/genética , Receptor alfa de Estrogênio/genética , Receptores Androgênicos/genética , 11-beta-Hidroxiesteroide Desidrogenase Tipo 2/antagonistas & inibidores , 17-Hidroxiesteroide Desidrogenases/genética , Inibidores da Aromatase/farmacologia , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Di-Hidrotestosterona/metabolismo , Estradiol/metabolismo , Feminino , Humanos , Esteril-Sulfatase/antagonistas & inibidores , Esteril-Sulfatase/genética , Esteril-Sulfatase/metabolismo
17.
FEBS J ; 286(11): 2155-2166, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30768851

RESUMO

Human 17ß-hydroxysteroid dehydrogenase type 1 (17ß-HSD1) catalyses the last step in estrogen activation and is thus involved in estrogen-dependent diseases (EDDs). Unlike other 17ß-HSD members, 17ß-HSD1 undergoes a significant substrate-induced inhibition that we have previously reported. Here we solved the binary and ternary crystal structures of 17ß-HSD1 in complex with estrone (E1) and cofactor analog NADP+ , demonstrating critical enzyme-substrate-cofactor interactions. These complexes revealed a reversely bound E1 in 17ß-HSD1 that provides the basis of the substrate inhibition, never demonstrated in estradiol complexes. Structural analysis showed that His221 is the key residue responsible for the reorganization and stabilization of the reversely bound E1, leading to the formation of a dead-end complex, which exists widely in NADP(H)-preferred enzymes for the regulation of their enzymatic activity. Further, a new inhibitor is proposed that may inhibit 17ß-HSD1 through the formation of a dead-end complex. This finding indicates a simple mechanism of enzyme regulation in the physiological background and introduces a pioneer inhibitor of 17ß-HSD1 based on the dead-end inhibition model for efficiently targeting EDDs. DATABASES: Coordinates and structure factors of 17ß-HSD1-E1 and 17ß-HSD1-E1-NADP+ have been deposited in the Protein Data Bank with accession code 6MNC and 6MNE respectively. ENZYMES: 17ß-hydroxysteroid dehydrogenase type 1 (17ß-HSD1) EC 1.1.1.62.


Assuntos
17-Hidroxiesteroide Desidrogenases/química , Estrona/química , NADP/química , Conformação Proteica , 17-Hidroxiesteroide Desidrogenases/genética , Sequência de Aminoácidos/genética , Sítios de Ligação/genética , Catálise , Cristalografia por Raios X , Inibidores Enzimáticos/química , Estrogênios/química , Estrogênios/genética , Humanos , Modelos Moleculares , Oxirredução , Ligação Proteica/genética , Especificidade por Substrato
18.
J Am Chem Soc ; 141(4): 1420-1424, 2019 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-30653304

RESUMO

Cyclin-dependent kinases (CDKs) are historic therapeutic targets implicated in tumorigenic events due to their critical involvement in the cell cycle phase. However, selectivity has proven to be a bottleneck, causing repeated failures. Previously, we reported CR6-interacting factor 1 (CRIF1), acting as a cell cycle negative regulator through interaction with CDK2. In the current report, we identified the CRIF1-CDK2 interaction interface by in silico studies and shortlisted interface inhibitors through virtual screening on CRIF1 using 40 678 drug-like compounds. These compounds were tested by cell proliferation assay, and four of these molecules were found to selectively inhibit the proliferation of osteosarcoma (OS) cell lines, but do not affect normal bone mesenchymal stem cells (BMSC). A binding study reveals significant affinities of the inhibitors on CRIF1. More importantly, treatment of the OS cells with a combination of ionizing radiation (IR) and the best-performing inhibitors remarkably increased IR inhibition potential from 19.9% to 59.6%. This occurred by selectively promoting G2/M arrest and apoptosis related to CDK2 overactivation in OS cells but not in BMSC and was supported by significant CDK2 phosphorylation modifications. Knocking down of CRIF1 by siRNA treatment showed similar effects to the interface inhibitors. Together we substantiate the identification of novel lead molecules, which may provide a new treatment to overcome selectivity issues and enhance the radiosensitivity of tumor cells, opening a conceptually novel strategy of CDK-targeting for different cancer types.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Quinase 2 Dependente de Ciclina/metabolismo , Radiossensibilizantes/farmacologia , Ciclo Celular/efeitos dos fármacos , Ciclo Celular/efeitos da radiação , Proteínas de Ciclo Celular/química , Linhagem Celular Tumoral , Quinase 2 Dependente de Ciclina/química , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Modelos Moleculares , Ligação Proteica/efeitos dos fármacos , Conformação Proteica
19.
J Steroid Biochem Mol Biol ; 186: 61-65, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30227243

RESUMO

Human 17ß-hydroxysteroid dehydrogenase (17ß-HSD) type 1 and 7 catalyze the final step of estrogen activation and the first step in androgen inactivation. It has been shown in breast cancer cells that DHT has a suppression effect on cell proliferation, counteracting the estrogen growth effect. However, the exact kinetic function of 17ß-HSD7 in steroidogenesis was not determined. Here we report the steady-state kinetics and binding study for 17ß-HSD7 with estrone or DHT as substrates and NADPH as cofactor. 17ß-HSD7 has been overexpressed in E. coli and purified. For both substrates, kinetics of 17ß-HSD7 demonstrates positive cooperativity. The K0.5 value is 5.2 ± 0.4 µM and 14.4 ± 0.8 µM and the kcat is 0.0063 ± 0.0003 s-1 and 0.0153 ± 0.0007 s-1 for the reduction of E1 and DHT, respectively. The binding study shows a similar affinity with a dissociation constant of 5.2 ± 0.5 µM and 11 ± 1 µM for E1 and DHT, respectively. Our kinetic and binding results reveal a positive cooperativity for 17ß-HSD7 to both the E1 and DHT with a similar affinity, while 17ß-HSD1 demonstrated a significantly higher affinity toward E1 than DHT, but with a strong E1 substrate inhibition. These results strongly support that the inhibition of 17ß-HSD7 constitutes the basis of breast cancer cell proliferation decreasing that led to the shrinkage of xenograft ER + breast tumor mice model.


Assuntos
17-Hidroxiesteroide Desidrogenases/metabolismo , Androgênios/metabolismo , Estrogênios/metabolismo , Di-Hidrotestosterona/metabolismo , Estrona/metabolismo , Humanos , Cinética , NADP/metabolismo , Especificidade por Substrato
20.
Biotechnol Rep (Amst) ; 21: e00295, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30568889

RESUMO

Cold-active lipases are gaining special attention nowadays as they are increasingly used in various industries such as fine chemical synthesis, food processing, and washer detergent. In the present study, an extracellular lipase gene from Yarrowia lipolytica (LIPY8) was cloned and expressed by baculovirus expression system. The recombinant lipase (LipY8p) was purified using chromatographic techniques, resulting in a purification factor of 25.7-fold with a specific activity of 1102.9U/mg toward olive oil. The apparent molecular mass of purified LipY8p was 40 kDa. The enzyme was most active at pH 7.5 and 17 °C. It exhibited maximum activity toward medium chain (C10) esters. The presence of transition metals such as Zn2+, Cu2+, and Ni2+ strongly inhibited the enzyme activity, which was enhanced by EDTA. The lipase activity was affected by detergents and was elevated by various organic solvents at 10% (v/v). These enzymatic properties make this lipase of considerable potential for biotechnological applications.

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