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1.
J Cell Biochem ; 121(4): 2756-2769, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31693255

RESUMEN

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.


Asunto(s)
Andrógenos/metabolismo , Neoplasias de la Mama/metabolismo , Estrógenos/metabolismo , Neoplasias de la Próstata/metabolismo , Animales , Línea Celular Tumoral , Relación Dosis-Respuesta a Droga , Estradiol , Femenino , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Masculino , Fosforilación , Receptores Androgénicos/metabolismo , Receptores de Estrógenos/metabolismo , Riesgo , Transducción de Señal
2.
J Am Chem Soc ; 141(4): 1420-1424, 2019 01 30.
Artículo en Inglés | MEDLINE | ID: mdl-30653304

RESUMEN

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.


Asunto(s)
Proteínas de Ciclo Celular/metabolismo , Quinasa 2 Dependiente de la Ciclina/metabolismo , Fármacos Sensibilizantes a Radiaciones/farmacología , Ciclo Celular/efectos de los fármacos , Ciclo Celular/efectos de la radiación , Proteínas de Ciclo Celular/química , Línea Celular Tumoral , Quinasa 2 Dependiente de la Ciclina/química , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Modelos Moleculares , Unión Proteica/efectos de los fármacos , Conformación Proteica
3.
Phys Rev Lett ; 120(18): 183602, 2018 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-29775362

RESUMEN

Quantum memory is an important component in the long-distance quantum communication based on the quantum repeater protocol. To outperform the direct transmission of photons with quantum repeaters, it is crucial to develop quantum memories with high fidelity, high efficiency and a long storage time. Here, we achieve a storage efficiency of 92.0 (1.5)% for a coherent optical memory based on the electromagnetically induced transparency scheme in optically dense cold atomic media. We also obtain a useful time-bandwidth product of 1200, considering only storage where the retrieval efficiency remains above 50%. Both are the best record to date in all kinds of schemes for the realization of optical memory. Our work significantly advances the pursuit of a high-performance optical memory and should have important applications in quantum information science.

4.
Biochem J ; 473(8): 1037-46, 2016 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-26929402

RESUMEN

Human 3α-HSD3 (3α-hydroxysteroid dehydrogenase type 3) plays an essential role in the inactivation of the most potent androgen 5α-DHT (5α-dihydrotestosterone). The present study attempts to obtain the important structure of 3α-HSD3 in complex with 5α-DHT and to investigate the role of 3α-HSD3 in breast cancer cells. We report the crystal structure of human 3α-HSD3·NADP(+)·A-dione (5α-androstane-3,17-dione)/epi-ADT (epiandrosterone) complex, which was obtained by co-crystallization with 5α-DHT in the presence of NADP(+) Although 5α-DHT was introduced during the crystallization, oxidoreduction of 5α-DHT occurred. The locations of A-dione and epi-ADT were identified in the steroid-binding sites of two 3α-HSD3 molecules per crystal asymmetric unit. An overlay showed that A-dione and epi-ADT were oriented upside-down and flipped relative to each other, providing structural clues for 5α-DHT reverse binding in the enzyme with the generation of different products. Moreover, we report the crystal structure of the 3α-HSD3·NADP(+)·4-dione (4-androstene-3,17-dione) complex. When a specific siRNA (100 nM) was used to suppress 3α-HSD3 expression without interfering with 3α-HSD4, which shares a highly homologous active site, the 5α-DHT concentration increased, whereas MCF7 cell growth was suppressed. The present study provides structural clues for 5α-DHT reverse binding within 3α-HSD3, and demonstrates for the first time that down-regulation of 3α-HSD3 decreases MCF7 breast cancer cell growth.


Asunto(s)
3-alfa-Hidroxiesteroide Deshidrogenasa (B-Específica)/química , Dihidrotestosterona/química , Regulación hacia Abajo/fisiología , Inhibidores de Crecimiento/química , 3-alfa-Hidroxiesteroide Deshidrogenasa (B-Específica)/metabolismo , Sitios de Unión/fisiología , Cristalización , Dihidrotestosterona/metabolismo , Inhibidores de Crecimiento/metabolismo , Humanos , Células MCF-7 , Unión Proteica/fisiología , Estructura Secundaria de Proteína , Difracción de Rayos X
5.
J Am Chem Soc ; 138(50): 16212-16215, 2016 12 21.
Artículo en Inglés | MEDLINE | ID: mdl-27998085

RESUMEN

Zika virus (ZIKV) is an emerging mosquito-borne virus recently linked to intrauterine growth restriction including abnormal fetal brain development. The recent outbreak of ZIKV reached pandemic level resulting in an alarming public health emergency. At present, there is limited understanding of the infectious mechanism and no approved therapy. Nonstructural protein 5 is essential for capping and replication of viral RNA and comprises a methyltransferase (MTase) and RNA dependent RNA polymerase domain. Here we used molecular modeling to obtain the structure of ZIKV MTase and molecular docking to identify the additional hydrophobic region uniquely conserved in flavivirus MTase that can be used as a druggable site. Subsequently, a virtual screening with a library of 28 341 compounds identified 10 best hits showing decisive contacts with the MTase. In vitro efficacy analysis of these compounds against ZIKV, by plaque reduction assay, has confirmed four of the top scored ligands (Life Chemicals ID: F3043-0013, F0922-0796, F1609-0442, and F1750-0048) having EC50 (50% effective concentration) values of 4.8 ± 2.3, 12.5 ± 7.4, 17.5 ± 8.4, and 17.6 ± 3.1 µM respectively, identifying lead compounds for anti-ZIKV drug development.


Asunto(s)
Descubrimiento de Drogas , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacología , Metiltransferasas/antagonistas & inhibidores , Proteínas no Estructurales Virales/química , Proteínas no Estructurales Virales/farmacología , Virus Zika/enzimología , Evaluación Preclínica de Medicamentos , Metiltransferasas/química , Modelos Moleculares , Conformación Proteica en Hélice alfa , Conformación Proteica en Lámina beta
6.
J Steroid Biochem Mol Biol ; 242: 106544, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38754521

RESUMEN

Sex steroid hormones such as estrogen estradiol (E2) and androgen dihydrotestosterone (DHT) are involved in the development of hormone-dependent cancers. Blockade of 17ß-hydroxysteroid dehydrogenase type 7 (17ß-HSD7), a member of the short chain dehydrogenase/reductase superfamily, is thought to decrease E2 levels while increasing those of DHT. Therefore, its unique double action makes this enzyme as an interesting drug target for treatment of breast cancer. The chemical synthesis, molecular characterization, and preliminary biological evaluation as 17ß-HSD7 inhibitors of novel carbamate derivatives 3 and 4 are described. Like previous 17ß-HSD7 inhibitors 1 and 2, compounds 3 and 4 bear a hydrophobic nonyl side chain at the C-17ß position of a 4-aza-5α-androstane nucleus, but compound 3 has an oxygen atom replacing the CH2 in the steroid A-ring C-2 position, while compound 4 has a C17-spiranic E-ring containing a carbamate function. They both inhibited the in vitro transformation of estrone (E1) into E2 by 17ß-HSD7, but the introduction of a (17 R)-spirocarbamate is preferable to replacing C-2 methylene with an oxygen atom since compound 4 (IC50 = 63 nM) is an inhibitor 14 times more powerful than compound 3 (IC50 = 900 nM). Furthermore, when compared to the reference inhibitor 1 (IC50 = 111 nM), the use of a C17-spiranic E-ring made it possible to introduce differently the hydrophobic nonyl side chain, without reducing the inhibitory activity.


Asunto(s)
17-Hidroxiesteroide Deshidrogenasas , Inhibidores Enzimáticos , 17-Hidroxiesteroide Deshidrogenasas/antagonistas & inhibidores , 17-Hidroxiesteroide Deshidrogenasas/metabolismo , Humanos , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/farmacología , Estradiol/química , Estradiol/metabolismo , Estradiol/farmacología , Carbamatos/química , Carbamatos/farmacología , Carbamatos/síntesis química , Estrona/química , Estrona/farmacología , Estrona/síntesis química
7.
Viruses ; 15(2)2023 02 20.
Artículo en Inglés | MEDLINE | ID: mdl-36851795

RESUMEN

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.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , Pandemias , Antivirales/farmacología , Péptido Hidrolasas
8.
Bioengineering (Basel) ; 10(8)2023 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-37627846

RESUMEN

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.

9.
J Steroid Biochem Mol Biol ; 228: 106246, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36634828

RESUMEN

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.


Asunto(s)
17-Hidroxiesteroide Deshidrogenasas , NAD , Humanos , 17-Hidroxiesteroide Deshidrogenasas/metabolismo , Sitios de Unión , Inhibidores Enzimáticos/farmacología , Inhibidores Enzimáticos/química , Estrógenos , NAD/metabolismo , NADP/metabolismo , Unión Proteica , Especificidad por Sustrato
10.
Breast Cancer Res ; 14(3): R92, 2012 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-22691413

RESUMEN

INTRODUCTION: Human 17beta-hydroxysteroid dehydrogenase type 1 (17ß-HSD1) is a steroid-converting enzyme that has long been known to play critical roles in estradiol synthesis and more recently in dihydrotestosterone (DHT) inactivation, showing a dual function that promotes breast cancer cell proliferation. Previously, we reported the first observation of the influence of the enzyme on endogenous estrogen-responsive gene expression. Here, we demonstrate the impact of 17ß-HSD1 expression on the breast cancer cell proteome and investigate its role in cell migration. METHODS: 17ß-HSD1 was stably transfected in MCF7 cells and the proteome of the generated cells overexpressing 17ß-HSD1 (MCF7-17ßHSD1 cells) was compared to that of the wild type MCF7 cells. Proteomics study was performed using two-dimensional gel electrophoresis followed by mass spectrometry analysis of differentially expressed protein spots. Reverse transcription quantitative real-time PCR (RT-qPCR) was used to investigate the transcription of individual gene. The effect of 17ß-HSD1 on MCF7 cell migration was verified by a wound-healing assay. RESULTS: Proteomic data demonstrate that the expression of more than 59 proteins is modulated following 17ß-HSD1 overexpression. 17ß-HSD1 regulates the expression of important genes and proteins that are relevant to cell growth control, such as BRCA2 and CDKN1A interacting protein (BCCIP) and proliferating cell nuclear antigen (PCNA) which are down- and upregulated in MCF7-17ßHSD1 cells, respectively. RT-qPCR data reveal that 17ß-HSD1 increases the mRNA levels of estrogen receptors (ER) alpha and beta by 171 and 120%, respectively, while decreasing that of the androgen receptor by 64%. Interestingly, 17ß-HSD1 increases the mRNA transcript (by 3.6 times) and the protein expression of the metastasis suppressor gene nm23-H1 and the expression of the two enzymes are closely correlated. We have further shown that 17ß-HSD1 expression is associated with an increase of MCF7 cell migration. CONCLUSIONS: In addition to the regulation of important genes, we have demonstrated for the first time that 17ß-HSD1 increases breast cancer cell migration, in spite of its positive regulation of the antimetastatic gene NM23. This is also correlated to its stimulation of breast cancer cell growth, further confirming its targeting in ER positive breast cancer. The novel findings in this study suggest several directions for future research on the contribution of 17ß-HSD1 to breast cancer progression and related treatment.


Asunto(s)
Movimiento Celular , Estradiol Deshidrogenasas/metabolismo , Nucleósido Difosfato Quinasas NM23/metabolismo , ARN Mensajero/metabolismo , Proteína BRCA2/metabolismo , Neoplasias de la Mama/metabolismo , Proteínas de Unión al Calcio/metabolismo , Proteínas de Ciclo Celular/metabolismo , Línea Celular Tumoral , Proliferación Celular , Estradiol Deshidrogenasas/genética , Receptor alfa de Estrógeno/genética , Receptor beta de Estrógeno/genética , Femenino , Humanos , Células MCF-7 , Proteínas Nucleares/metabolismo , Antígeno Nuclear de Célula en Proliferación/metabolismo , Análisis por Matrices de Proteínas , Proteoma/análisis , Interferencia de ARN , ARN Mensajero/genética , ARN Interferente Pequeño , Receptores Androgénicos/genética
11.
Cancers (Basel) ; 14(4)2022 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-35205737

RESUMEN

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.

12.
Antimicrob Agents Chemother ; 55(9): 4019-27, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21709106

RESUMEN

Selection of human cytomegalovirus variants in the presence of ganciclovir or foscarnet led to 18 DNA polymerase mutations, 14 of which had not been previously studied. Using bacterial artificial chromosome technology, each of these mutations was individually transferred into the genome of a reference strain. Following reconstitution of infectious viral stocks, each mutant was assessed for its drug susceptibility and growth kinetics in cell culture. Computer-assisted three-dimensional (3D) modeling of the polymerase was also used to position each of the mutations in one of four proposed structural domains and to predict their influence on structural stability of the protein. Among the 10 DNA polymerase mutations selected with ganciclovir, 7 (P488R, C539R, L545S, V787L, V812L, P829S, and L862F) were associated with ganciclovir resistance, whereas 2 (F595I and V946L) conferred only foscarnet resistance. Among the eight mutations selected with foscarnet, only two (T552N and S585A) conferred foscarnet resistance, whereas four (N408D, K500N, L802V, and L957F) had an impact on ganciclovir susceptibility. Surprisingly, the combination of mutations, some of which were not associated with resistance for a specific antiviral, resulted in increasing resistance effects. 3D modeling suggested that none of the mutated residues were directly involved in the polymerase catalytic site but rather had an influence on drug susceptibility by modifying the structural flexibility of the protein. Our study significantly adds to the number of DNA polymerase mutations conferring in vitro drug resistance and emphasizes the point that evaluation of individual mutations may not accurately reflect the phenotype conferred by multiple mutations.


Asunto(s)
Antivirales/farmacología , Citomegalovirus/efectos de los fármacos , Foscarnet/farmacología , Ganciclovir/farmacología , Células Cultivadas , Citomegalovirus/enzimología , Citomegalovirus/genética , ADN Polimerasa Dirigida por ADN/genética , Genotipo , Humanos , Mutación , Fenotipo , Recombinación Genética/genética , Proteínas Virales/genética
13.
J Steroid Biochem Mol Biol ; 214: 105963, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34400276

RESUMEN

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.


Asunto(s)
Neoplasias de la Mama/tratamiento farmacológico , 17-Hidroxiesteroide Deshidrogenasas/metabolismo , Sitio Alostérico , Andrógenos/metabolismo , Neoplasias de la Mama/metabolismo , Catálisis , Colesterol/metabolismo , Dihidrotestosterona/metabolismo , Ensayos de Selección de Medicamentos Antitumorales , Inhibidores Enzimáticos/farmacología , Estradiol/metabolismo , Estrógenos/metabolismo , Estrona/metabolismo , Femenino , Humanos , Cinética , Ligandos , Unión Proteica , Análisis de Regresión
14.
Biomed Pharmacother ; 137: 111232, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33486202

RESUMEN

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.


Asunto(s)
Antivirales/farmacología , Tratamiento Farmacológico de COVID-19 , COVID-19 , SARS-CoV-2 , COVID-19/epidemiología , Desarrollo de Medicamentos/métodos , Reposicionamiento de Medicamentos/métodos , Humanos , SARS-CoV-2/efectos de los fármacos , SARS-CoV-2/fisiología , Resultado del Tratamiento , Proteínas Virales/antagonistas & inhibidores , Proteínas Virales/genética , Internalización del Virus/efectos de los fármacos
15.
Am J Cancer Res ; 11(11): 5358-5373, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34873465

RESUMEN

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.

16.
J Biol Chem ; 284(39): 26676-84, 2009 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-19640842

RESUMEN

The double-headed arrowhead protease inhibitors API-A and -B from the tubers of Sagittaria sagittifolia (Linn) feature two distinct reactive sites, unlike other members of their family. Although the two inhibitors have been extensively characterized, the identities of the two P1 residues in both API-A and -B remain controversial. The crystal structure of a ternary complex at 2.48 A resolution revealed that the two trypsins bind on opposite sides of API-A and are 34 A apart. The overall fold of API-A belongs to the beta-trefoil fold and resembles that of the soybean Kunitz-type trypsin inhibitors. The two P1 residues were unambiguously assigned as Leu(87) and Lys(145), and their identities were further confirmed by site-directed mutagenesis. Reactive site 1, composed of residues P5 Met(83) to P5' Ala(92), adopts a novel conformation with the Leu(87) completely embedded in the S1 pocket even though it is an unfavorable P1 residue for trypsin. Reactive site 2, consisting of residues P5 Cys(141) to P5' Glu(150), binds trypsin in the classic mode by employing a two-disulfide-bonded loop. Analysis of the two binding interfaces sheds light on atomic details of the inhibitor specificity and also promises potential improvements in enzyme activity by engineering of the reactive sites.


Asunto(s)
Proteínas de Plantas/química , Conformación Proteica , Estructura Terciaria de Proteína , Tripsina/química , Secuencia de Aminoácidos , Sitios de Unión , Cristalografía por Rayos X , Modelos Moleculares , Datos de Secuencia Molecular , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Unión Proteica , Homología de Secuencia de Aminoácido , Tripsina/metabolismo
17.
Biochem J ; 424(3): 357-66, 2009 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-19929851

RESUMEN

Oestradiol is a well-characterized sex hormone that stimulates breast cancer and other oestrogen-related diseases. 17beta-hydroxysteroid dehydrogenase type 1 (17beta-HSD1) catalyses the last step in the synthesis of oestradiol and androstenediol in breast tumour tissue. The enzyme's high expression and activity after simultaneous blockade of oestrogen receptors and inhibition of aromatase in the tumour shows the necessity for its inhibition as a requirement for breast cancer therapy. In the present paper, we report structures of the binary and ternary complexes of 17beta-HSD1 with a new inhibitor E2B {3-[3',17'beta-dihydroxyestra-1',3',5'(10')-trien-16'beta-methyl]benzamide}, and the enzyme inhibition by the later. The IC50 value for E2B was determined to be 42 nM in T47D cells. Multiple interactions between E2B and the enzyme include hydrogen bonds and hydrophobic interactions, as well as pi-pi interactions. A kinetic study demonstrated that E2B inhibits the enzyme's reduction forming oestradiol from oestrone, with a Ki of 0.9+/-0.15 nM. Such strong inhibition is in agreement with its extensive interaction with the enzyme, suggesting its potential as a lead compound for breast cancer therapy. In fact, this possibility is enhanced by its capacity for cell penetration similar to natural steroids. Such inhibitors that block oestrogen synthesis to suppress the sulfatase pathway producing oestradiol can be used in adjuvant therapies with oestrogen receptor blockade, opening a new orientation of breast cancer treatment.


Asunto(s)
17-Hidroxiesteroide Deshidrogenasas/química , Benzamidas/química , Inhibidores Enzimáticos/química , Estradiol/análogos & derivados , Conformación Molecular , Estructura Terciaria de Proteína , 17-Hidroxiesteroide Deshidrogenasas/antagonistas & inhibidores , 17-Hidroxiesteroide Deshidrogenasas/metabolismo , Benzamidas/farmacología , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/enzimología , Neoplasias de la Mama/patología , Línea Celular , Línea Celular Tumoral , Cristalización , Cristalografía por Rayos X , Inhibidores Enzimáticos/metabolismo , Inhibidores Enzimáticos/farmacología , Estradiol/química , Estradiol/metabolismo , Estradiol/farmacología , Estrona/química , Estrona/metabolismo , Femenino , Humanos , Enlace de Hidrógeno , Interacciones Hidrofóbicas e Hidrofílicas , Cinética , Modelos Moleculares , Estructura Molecular , Unión Proteica
18.
J Steroid Biochem Mol Biol ; 196: 105494, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31610224

RESUMEN

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.


Asunto(s)
Neoplasias de la Mama/genética , Carcinoma Ductal de Mama/genética , Sistema Enzimático del Citocromo P-450/genética , Hormonas Esteroides Gonadales/genética , Receptores Citoplasmáticos y Nucleares/genética , 17-Hidroxiesteroide Deshidrogenasas/genética , 17-Hidroxiesteroide Deshidrogenasas/metabolismo , Neoplasias de la Mama/epidemiología , Neoplasias de la Mama/metabolismo , Carcinoma Ductal de Mama/epidemiología , Carcinoma Ductal de Mama/metabolismo , Estudios de Cohortes , Sistema Enzimático del Citocromo P-450/metabolismo , Bases de Datos Factuales/estadística & datos numéricos , Estradiol/farmacología , Femenino , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Hormonas Esteroides Gonadales/metabolismo , Humanos , Sector Público/estadística & datos numéricos , Receptores Citoplasmáticos y Nucleares/metabolismo
19.
J Steroid Biochem Mol Biol ; 198: 105559, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31783154

RESUMEN

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.


Asunto(s)
Regulación Neoplásica de la Expresión Génica , Neoplasias de la Próstata/genética , 11-beta-Hidroxiesteroide Deshidrogenasa de Tipo 1/genética , 3-Oxo-5-alfa-Esteroide 4-Deshidrogenasa/genética , Regulación hacia Abajo , Humanos , Hidroxiesteroide Deshidrogenasas/genética , Masculino , Neoplasias de la Próstata/enzimología , Neoplasias de la Próstata/patología , Receptores Androgénicos/genética , Receptores de Glucocorticoides/genética , Receptores de Progesterona/genética , Regulación hacia Arriba
20.
Sci Rep ; 10(1): 13990, 2020 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-32814785

RESUMEN

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.

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