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1.
Microorganisms ; 12(3)2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38543547

RESUMO

Protaetia brevitarsis larvae are farm-raised for food, are used in traditional East Asian medicine, and convert organic waste into biofertilizers. Here, the comparative analysis of the gut microbiota of third-instar larvae obtained from five different farms was investigated using 16S rRNA microbial profiling. Species richness, evenness, and diversity results using α-diversity analysis (observed species, Chao1, Shannon, Simpson) were similar between farms, except for those between the TO and KO farms. ß-diversity was significantly different in distribution and relative abundance between farms (PERMANOVA, pseudo-F = 13.20, p = 0.001). At the phylum level, Bacillota, Bacteroidota, Actinomycetota, and Pseudomonadota were the most dominant, accounting for 73-88% of the hindgut microbial community. At the genus level, Tuberibacillus, Proteiniphilum, Desulfovibrio, Luoshenia, and Thermoactinomyces were the most abundant. Although oak sawdust was the main feed component, there were large variations in distribution and relative abundance across farms at the phylum and genus levels. Venn diagram and linear discriminant analysis effect size analyses revealed large variations in the hindgut microbial communities of P. brevitarsis larvae between farms. These results suggest environmental factors were more important than feed ingredients or genetic predisposition for the establishment of the intestinal microbiota of P. brevitarsis larvae. These findings serve as reference data to understand the intestinal microbiota of P. brevitarsis larvae.

2.
Microbiol Resour Announc ; 12(10): e0055323, 2023 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-37754558

RESUMO

Soybean geminivirus A (SGVA), a member of the family Geminiviridae, was detected in a survey of early-stage soybean. The complete genome sequence of SGVA isolate Habin was determined, revealing its characteristics and similarity to Korean and Chinese isolates. This study contributes to understanding the impact of SGVA on soybean production.

3.
Plant Dis ; 2023 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-37194209

RESUMO

Tulip cultivation in Korea primarily uses imported bulbs due to the absence of domestic production. To ensure safety and sustainability, Korean authorities have implemented strict phytosanitary measures for five viruses: arabis mosaic virus, tobacco necrosis virus, tobacco ringspot virus, tomato black ring virus, and tomato bushy stunt virus. In April 2021, 86 tulip plants presented symptoms such as chlorotic mottle, mosaic, streak, stripe, yellowing of the leaves, and color breaking on flowers. These samples were collected to investigate the incidence of viruses in four Korean provinces (Gangwon, Gyeongbuk, Gyeongnam, and Chungnam). The leaves and petals from each individual sample (10 mg each) were pooled and ground using liquid nitrogen. Total RNA was extracted using a Maxwell® 16 LEV Plant RNA Kit (Promega, Madison, USA). A cDNA library was constructed using TruSeq Standard Total RNA with Ribo - Zero (Illumina, San Diego, USA) and sequenced on an Illumina NovaSeq 6000 platform (Macrogen, Seoul, Korea) with 100-bp paired-end reads. Trinity software identified tulip breaking virus (TBV), tulip virus X (TVX), and lily symptomless virus (LSV), which are known to occur in Korea (Bak et al. 2023) by de novo assembly of 628 million reads into 498,795 contigs. The contigs were annotated as previously described (Bak et al. 2022). Moreover, a contig (ON758350) related to olive mild mosaic virus (OMMV; genus Alphanecrovirus, family Tombusviridae) was identified through BLASTn analysis. This contig had a 99.27% nucleotide (nt) identity to OMMV PPO-L190209 (KU641010), which was assembled from 201,346 reads and spanned 3,713 bp. To confirm the presence of OMMV, a primer pair (5'-GAATGTCTGGCGTTAAGCG-3'/5'-GTGTCCTGCGCATCATACAC-3') was designed to amplify a 797-bp fragment of the coat protein gene. In RT-PCR, 31.4% (27/86) of samples were positive for OMMV and coinfected with TBV or TBV+LSV. Coinfection with TBV led to chlorotic mottling and stripes, whereas triple coinfection with TBV+LSV produced distinct yellow streaks and mosaic within the lesion boundaries. In contrast, solely TBV infection did not produce such symptoms. The samples infected with OMMV were exclusively collected from Gangwon and Gyeongnam. In each province, an RT-PCR amplicon was cloned, and subsequently sequenced (Bioneer, Daejeon, Korea). The obtained sequences were named CC (OM243091) and GS (OM243092), and they shared 98.6% and 98.9% identity with PPO-L190209 (KU641010), respectively. A bioassay was conducted using a leaf infected with OMMV CC and TBV to inoculate 13 indicator species in triplicate, including Capsicum annuum, Chenopodium amaranticolor, C. quinoa, Cucumis sativus, Nicotiana benthamiana, N. clevelandii, N. glutinosa, N. occidentalis, N. rustica, N. tabacum, Solanum lycopersicum, Tetragonia tetragonioides, and Tulipa gesneriana. The RT-PCR revealed positivity only for OMMV in the upper leaves of N. clevelandii, while all other species were negative with no symptoms. To our knowledge, this is the first report of OMMV occurring in tulips grown from imported bulbs in Korea, with no other known natural hosts such as olive tree (Cardoso et al. 2004), spinach (Gratsia et al. 2012), and corn salad (Verdin et al. 2018). The Korean OMMV isolates exhibited a high nt identity with the foreign isolate, and the samples were collected from farms that rely entirely on bulb imports for cultivation. These suggest that the outbreak of OMMV was likely caused by imported bulbs.

4.
AJR Am J Roentgenol ; 220(3): 389-397, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36169541

RESUMO

BACKGROUND. Specialized inferior vena cava (IVC) filter referral centers can achieve improved retrieval outcomes, potentially facilitating complex retrievals after long filter dwell times. OBJECTIVE. The purpose of this study was to determine the success rate of complex IVC filter retrievals at a large specialized IVC filter referral center and to identify predictors of adverse events during complex retrievals. METHODS. This retrospective study included patients who underwent complex IVC filter retrieval from March 2014 to June 2018 at a large regional health system with specialized complex retrieval referral centers and interventional radiologists with expertise in such procedures. Complex retrievals methods included a range of loop snare, coaxial sheath, forceps, and snare techniques. Data were collected from the electronic medical record. The success rate of complex retrieval was determined. Factors associated with adverse events during retrieval procedures were explored. RESULTS. The study included 125 patients (51 women, 74 men; mean age, 60 years). The mean filter dwell time at retrieval was 47.5 months (median, 21.8 months). The complex retrieval success rate was 99.2% on the first attempt and 100.0% overall. A total of 11.2% (14/125) of patients experienced an adverse event during retrieval, including 10.4% (13/125) with minor and 0.8% (1/125) with major events. Prolonged dwell time was the only indication for complex retrieval that was significantly associated with adverse events (adverse event rate, 16.7% for patients with this indication vs 5.1% for patients without this indication; p = .04). In multiple regression analysis, the only significant independent predictor of adverse events was a filter dwell time of 5 years or longer (odds ratio, 6.98 [95% CI, 1.64-29.81]; p = .009). CONCLUSION. In a specialized referral system with expertise in complex retrieval methods, high retrieval success rates can be achieved in patients who have filters with long dwell times. Nonetheless, longer dwell times are associated with adverse events during retrieval procedures. CLINICAL IMPACT. The observations support performing early filter retrieval and referring patients who have filters with prolonged dwell times to specialized centers.


Assuntos
Filtros de Veia Cava , Masculino , Humanos , Feminino , Pessoa de Meia-Idade , Fatores de Risco , Estudos Retrospectivos , Remoção de Dispositivo/métodos , Encaminhamento e Consulta , Veia Cava Inferior
5.
Per Med ; 19(5): 411-422, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35912812

RESUMO

Aim: The COVID-19 pandemic forced medical practices to augment healthcare delivery to remote and virtual services. We describe the results of a nationwide survey of cardiovascular professionals regarding telehealth perspectives. Materials & methods: A 31-question survey was sent early in the pandemic to assess the impact of COVID-19 on telehealth adoption & reimbursement. Results: A total of 342 clinicians across 42 states participated. 77% were using telehealth, with the majority initiating usage 2 months after the COVID-19 shutdown. A variety of video-based systems were used. Telehealth integration requirements differed, with electronic medical record integration being mandated in more urban than rural practices (70 vs 59%; p < 0.005). Many implementation barriers surfaced, with over 75% of respondents emphasizing reimbursement uncertainty and concerns for telehealth generalizability given the complexity of cardiovascular diseases. Conclusion: Substantial variation exists in telehealth practices. Further studies and legislation are needed to improve access, reimbursement and the quality of telehealth-based cardiovascular care.


As the COVID-19 pandemic was just beginning, the American College of Cardiology administered a survey to cardiology professionals across the USA regarding their preparedness for telehealth and video-visits. The results demonstrated rapid adoption of video based telehealth services, however revealed uncertainty for how to best use these services in different practice settings. Many providers expressed concerns about how these visits will be compensated, but fortunately federal agencies have dramatically changed the way telehealth is reimbursed as the pandemic has progressed. Further studies are needed to explore the impact of telehealth on healthcare inequality, however we hope that rather it serves to increase healthcare access to all.


Assuntos
COVID-19 , Cardiologia , Telemedicina , COVID-19/epidemiologia , Estudos Transversais , Humanos , Pandemias , Telemedicina/métodos , Estados Unidos/epidemiologia
9.
J Med Chem ; 59(5): 2005-24, 2016 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-26756222

RESUMO

First generation EGFR TKIs (gefitinib, erlotinib) provide significant clinical benefit for NSCLC cancer patients with oncogenic EGFR mutations. Ultimately, these patients' disease progresses, often driven by a second-site mutation in the EGFR kinase domain (T790M). Another liability of the first generation drugs is severe adverse events driven by inhibition of WT EGFR. As such, our goal was to develop a highly potent irreversible inhibitor with the largest selectivity ratio between the drug-resistant double mutants (L858R/T790M, Del/T790M) and WT EGFR. A unique approach to develop covalent inhibitors, optimization of reversible binding affinity, served as a cornerstone of this effort. PF-06459988 was discovered as a novel, third generation irreversible inhibitor, which demonstrates (i) high potency and specificity to the T790M-containing double mutant EGFRs, (ii) minimal intrinsic chemical reactivity of the electrophilic warhead, (iii) greatly reduced proteome reactivity relative to earlier irreversible EGFR inhibitors, and (iv) minimal activity against WT EGFR.


Assuntos
Descoberta de Drogas , Receptores ErbB/antagonistas & inibidores , Receptores ErbB/genética , Proteínas Mutantes/antagonistas & inibidores , Inibidores de Proteínas Quinases/farmacologia , Pirimidinas/farmacologia , Pirróis/farmacologia , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Relação Dose-Resposta a Droga , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Modelos Moleculares , Estrutura Molecular , Mutação , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/química , Pirimidinas/síntese química , Pirimidinas/química , Pirróis/síntese química , Pirróis/química , Relação Estrutura-Atividade , Células Tumorais Cultivadas
10.
Eur Urol ; 66(1): 145-55, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24411988

RESUMO

BACKGROUND: Although prostate cancer responds initially to androgen ablation therapies, progression to castration-resistant prostate cancer (CRPC) frequently occurs. Heat shock protein (Hsp) 90 inhibition is a rational therapeutic strategy for CRPC that targets key proteins such as androgen receptor (AR) and protein kinase B (Akt); however, most Hsp90 inhibitors trigger elevation of stress proteins like Hsp27 that confer tumor cell survival and treatment resistance. OBJECTIVE: We hypothesized that cotargeting the cytoprotective chaperone Hsp27 and Hsp90 would amplify endoplasmic reticulum (ER) stress and treatment-induced cell death in cancer. DESIGN, SETTING, AND PARTICIPANTS: Inducible and constitutive Hsp27 and other HSPs were measured by real-time reverse transcription-polymerase chain reaction and immunoblot assays. The combinations of OGX-427 with Hsp90 inhibitors were evaluated in vitro for LNCaP cell growth and apoptosis and in vivo in CRPC LNCaP xenograft models. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Tumor volumes were compared using the Kruskal-Wallis test. Overall survival was analyzed using Kaplan-Meier curves, and statistical significance was assessed with the log-rank test. RESULTS AND LIMITATIONS: Hsp90 inhibitors induced expression of HSPs in tumor cells and tissues in a dose- and time-dependent manner; in particular, Hsp27 mRNA and protein levels increased threefold. In vitro, OGX-427 synergistically enhanced Hsp90 inhibitor-induced suppression of cell growth and induced apoptosis by 60% as measured by increased sub-G1 fraction and poly(ADP-ribose) polymerase cleavage. These biologic events were accompanied by decreased expression of HSPs, Akt, AR, and prostate-specific antigen, and induction of ER stress markers (cleaved activating transcription factor 6, glucose-regulated protein 78, and DNA-damage-inducible transcript 3). In vivo, OGX-427 potentiated the anticancer effects of Hsp90 inhibitor PF-04929113 (orally, 25mg/kg) to inhibit tumor growth and prolong survival in CRPC LNCaP xenografts. CONCLUSIONS: HSP90 inhibitor-mediated induction of Hsp27 expression can be attenuated by OGX-427, resulting in increased ER stress and apoptosis, and synergistic inhibition of CRPC tumor growth. PATIENT SUMMARY: This study supports the development of targeted strategies using OGX-427 in combination with Hsp90 inhibitors to improve patient outcome in CRPC.


Assuntos
Antineoplásicos/farmacologia , Benzoquinonas/farmacologia , Retículo Endoplasmático/fisiologia , Proteínas de Choque Térmico HSP27/antagonistas & inibidores , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Compostos Heterocíclicos de 4 ou mais Anéis/farmacologia , Lactamas Macrocíclicas/farmacologia , Oligonucleotídeos/farmacologia , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Estresse Fisiológico/efeitos dos fármacos , Animais , Antineoplásicos/uso terapêutico , Apoptose/efeitos dos fármacos , Benzoquinonas/uso terapêutico , Linhagem Celular Tumoral , Chaperona BiP do Retículo Endoplasmático , Proteínas de Choque Térmico HSP27/genética , Proteínas de Choque Térmico HSP27/metabolismo , Proteínas de Choque Térmico HSP70/metabolismo , Proteínas de Choque Térmico HSP90/genética , Proteínas de Choque Térmico HSP90/metabolismo , Proteínas de Choque Térmico/metabolismo , Compostos Heterocíclicos de 4 ou mais Anéis/uso terapêutico , Humanos , Lactamas Macrocíclicas/uso terapêutico , Masculino , Camundongos , Oligonucleotídeos/uso terapêutico , Antígeno Prostático Específico/sangue , Neoplasias de Próstata Resistentes à Castração/metabolismo , Neoplasias de Próstata Resistentes à Castração/patologia , RNA/metabolismo , Taxa de Sobrevida , Fator de Transcrição CHOP/metabolismo , Resposta a Proteínas não Dobradas/efeitos dos fármacos
11.
Clin Cancer Res ; 20(3): 631-43, 2014 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-24240111

RESUMO

PURPOSE: Constitutive activation of phosphoinositide 3-kinase (PI3K) occurs frequently in many human tumors via either gene mutation in the p110α catalytic subunit of PI3K or functional loss of tumor suppressor PTEN. Patients with small-cell lung cancer (SCLC) have very poor prognosis and survival rates such that an effective targeted therapy is in strong demand for these patients. In this study, we characterized the highly selective oral PI3K inhibitor, PF-4989216, in preclinical SCLC models to investigate whether targeting the PI3K pathway is an effective targeted therapy option for SCLCs that harbor a PIK3CA mutation. EXPERIMENTAL DESIGN: A panel of SCLC cell lines with PIK3CA mutation or PTEN loss were treated with PF-4989216 in several in vitro assays, including PI3K pathway signaling, cell viability, apoptosis, cell-cycle progression, and cell transformation. SCLC cell lines that were sensitive in vitro to PF-4989216 were further evaluated by in vivo animal studies to determine the pharmacokinetic/pharmacodynamic relationship and tumor growth inhibition (TGI) by PF-4989216 treatment. RESULTS: PF-4989216 inhibited PI3K downstream signaling and subsequently led to apoptosis induction, and inhibition in cell viability, transformation, and xenograft tumor growth in SCLCs harboring PIK3CA mutation. In SCLCs with PTEN loss, PF-4989216 also inhibited PI3K signaling but did not induce BCL2-interacting mediator (BIM)-mediated apoptosis nor was there any effect on cell viability or transformation. These results implicate differential tumorigenesis and apoptosis mechanisms in SCLCs harboring PIK3CA mutation versus PTEN loss. CONCLUSIONS: Our results suggest that PF-4989216 is a potential cancer drug candidate for patients with SCLC with PIK3CA mutation but not PTEN loss.


Assuntos
Antineoplásicos/farmacologia , Neoplasias Pulmonares/genética , Inibidores de Fosfoinositídeo-3 Quinase , Carcinoma de Pequenas Células do Pulmão/genética , Tiofenos/farmacologia , Triazóis/farmacologia , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Classe I de Fosfatidilinositol 3-Quinases , Ensaio de Imunoadsorção Enzimática , Feminino , Citometria de Fluxo , Humanos , Immunoblotting , Camundongos , Camundongos SCID , Mutação , Fosfatidilinositol 3-Quinases/genética , Inibidores de Proteínas Quinases/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto
12.
PLoS One ; 8(11): e79655, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24244539

RESUMO

MicroRNAs (miRNAs) have been implicated in the orchestration of diverse cellular processes including differentiation, proliferation, and apoptosis and are believed to play pivotal roles as oncogenes and tumor suppressors. miR-122, a liver specific miRNA, is significantly down-regulated in most hepatocellular carcinomas (HCCs) but its role in tumorigenesis remains poorly understood. Here we identify AKT3 as a novel and direct target of miR-122. Restoration of miR-122 expression in HCC cell lines decreases AKT3 levels, inhibits cell migration and proliferation, and induces apoptosis. These anti-tumor phenotypes can be rescued by reconstitution of AKT3 expression indicating the essential role of AKT3 in miR-122 mediated HCC transformation. In vivo, restoration of miR-122 completely inhibited xenograft growth of HCC tumor in mice. Our data strongly suggest that miR-122 is a tumor suppressor that targets AKT3 to regulate tumorigenesis in HCCs and a potential therapeutic candidate for liver cancer.


Assuntos
Carcinoma Hepatocelular/genética , Transformação Celular Neoplásica/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias Hepáticas/genética , MicroRNAs/genética , Proteínas Proto-Oncogênicas c-akt/genética , Regiões 3' não Traduzidas , Animais , Apoptose/genética , Pareamento de Bases , Sequência de Bases , Carcinoma Hepatocelular/metabolismo , Linhagem Celular Transformada , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células , Modelos Animais de Doenças , Feminino , Humanos , Neoplasias Hepáticas/metabolismo , Camundongos , MicroRNAs/química , MicroRNAs/metabolismo , Proteínas Proto-Oncogênicas c-akt/química , Proteínas Proto-Oncogênicas c-akt/metabolismo , Interferência de RNA , Ensaios Antitumorais Modelo de Xenoenxerto
13.
PLoS One ; 8(4): e62170, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23637992

RESUMO

Patients with triple-negative breast cancers (TNBCs) typically have a poor prognosis. TNBCs are characterized by their resistance to apoptosis, aggressive cellular proliferation, migration and invasion, and currently lack molecular markers and effective targeted therapy. Recently, miR-221/miR-222 have been shown to regulate ERα expression and ERα-mediated signaling in luminal breast cancer cells, and also to promote EMT in TNBCs. In this study, we characterized the role of miR-221 in a panel of TNBCs as compared to other breast cancer types. miR-221 knockdown not only blocked cell cycle progression, induced cell apoptosis, and inhibited cell proliferation in-vitro but it also inhibited in-vivo tumor growth by targeting p27(kip1). Furthermore, miR-221 knockdown inhibited cell migration and invasion by altering E-cadherin expression, and its regulatory transcription factors Snail and Slug in human TNBC cell lines. Therefore, miR-221 functions as an oncogene and is essential in regulating tumorigenesis in TNBCs both in vitro as well as in vivo.


Assuntos
Carcinogênese/genética , MicroRNAs/genética , Neoplasias de Mama Triplo Negativas/genética , Animais , Apoptose/genética , Caderinas/genética , Caderinas/metabolismo , Carcinogênese/metabolismo , Ciclo Celular/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células , Inibidor de Quinase Dependente de Ciclina p27/genética , Inibidor de Quinase Dependente de Ciclina p27/metabolismo , Transição Epitelial-Mesenquimal/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Camundongos , MicroRNAs/metabolismo , Fatores de Transcrição da Família Snail , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Neoplasias de Mama Triplo Negativas/metabolismo , Neoplasias de Mama Triplo Negativas/patologia , Carga Tumoral/genética
14.
Curr Cancer Drug Targets ; 13(3): 267-77, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23297825

RESUMO

The mammalian target of rapamycin (mTOR) plays a critical role in the regulation of cell growth, proliferation,and metabolism by integrating growth factor stimulation and energy/nutrient input through a complex signaling network.The mTOR kinase is a part of two structurally and functionally distinct multiple protein complexes, mTORC1 and mTORC2. The mammalian target of rapamycin complex 1 (mTORC1) is rapamycin-sensitive and mediates temporal control of cell growth by regulating several cellular processes, such as translation, transcription, and nutrient transport while the mammalian target of rapamycin complex 2 (mTORC2) is in sensitive to rapamycin and is involved in spatial control of cell growth via cytoskeleton regulation. Here we discuss the mechanism of mTOR regulation in tumor malignancy through a variety of signaling pathways and the potential of mTOR inhibitors for the treatment of cancer.


Assuntos
Antineoplásicos/uso terapêutico , Terapia de Alvo Molecular , Proteínas de Neoplasias/antagonistas & inibidores , Neoplasias/tratamento farmacológico , Inibidores de Proteínas Quinases/uso terapêutico , Transdução de Sinais/efeitos dos fármacos , Serina-Treonina Quinases TOR/antagonistas & inibidores , Animais , Antineoplásicos/farmacologia , Transformação Celular Neoplásica/efeitos dos fármacos , Transformação Celular Neoplásica/metabolismo , Humanos , Isoenzimas/antagonistas & inibidores , Isoenzimas/metabolismo , Proteínas de Neoplasias/metabolismo , Neoplasias/metabolismo , Neoplasias/prevenção & controle , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Serina-Treonina Quinases TOR/metabolismo
15.
ACS Med Chem Lett ; 4(1): 91-7, 2013 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-24900568

RESUMO

PI3K, AKT, and mTOR are key kinases from PI3K signaling pathway being extensively pursued to treat a variety of cancers in oncology. To search for a structurally differentiated back-up candidate to PF-04691502, which is currently in phase I/II clinical trials for treating solid tumors, a lead optimization effort was carried out with a tricyclic imidazo[1,5]naphthyridine series. Integration of structure-based drug design and physical properties-based optimization yielded a potent and selective PI3K/mTOR dual kinase inhibitor PF-04979064. This manuscript discusses the lead optimization for the tricyclic series, which both improved the in vitro potency and addressed a number of ADMET issues including high metabolic clearance mediated by both P450 and aldehyde oxidase (AO), poor permeability, and poor solubility. An empirical scaling tool was developed to predict human clearance from in vitro human liver S9 assay data for tricyclic derivatives that were AO substrates.

16.
PLoS One ; 7(10): e48402, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23119004

RESUMO

Binding of IGF to IGF-IR activates PI3K to generate PIP3 which in turn recruits and activates proteins that contain a pleckstrin homology (PH) domain, including AKT and PDK1. PDK1 is highly expressed in breast tumor samples and breast cancer cell lines. Here we demonstrate that targeting PDK1 with the potent and selective PDK1 inhibitor PF-5177624 in the IGF-PI3K pathway blocks breast cancer cell proliferation and transformation. Breast cancer cell lines MCF7 and T47D, representing the luminal ER positive subtype and harboring PIK3CA mutations, were most responsive to IGF-I induction resulting in upregulated AKT and p70S6K phosphorylation via PDK1 activation. PF-5177624 downregulated AKT and p70S6K phosphorylation, blocked cell cycle progression, and decreased cell proliferation and transformation to block IGFR-I induced activation in breast cancer cells. These results may provide insight into clinical strategies for developing an IGFR-I inhibitor and/or a PDK1 inhibitor in luminal breast cancer patients.


Assuntos
Neoplasias da Mama/patologia , Fator de Crescimento Insulin-Like I/antagonistas & inibidores , Fator de Crescimento Insulin-Like I/farmacologia , Terapia de Alvo Molecular/métodos , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Quinases S6 Ribossômicas 70-kDa/metabolismo , Proteínas Quinases Dependentes de 3-Fosfoinositídeo , Neoplasias da Mama/tratamento farmacológico , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Transformação Celular Neoplásica/efeitos dos fármacos , Ativação Enzimática/efeitos dos fármacos , Humanos , Fosforilação/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Serina-Treonina Quinases/antagonistas & inibidores
17.
Bioorg Med Chem Lett ; 22(15): 5114-7, 2012 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-22765900

RESUMO

Novel conformationally-restricted mTOR kinase inhibitors with cyclic sulfone scaffold were designed. Synthesis and structure-activity relationship (SAR) studies are described with emphasis on optimization of the mTOR potency and selectivity against class I PI3Kα kinase. PF-05139962 was identified with excellent mTOR biochemical inhibition, cellular potency, kinase selectivity and in vitro ADME properties.


Assuntos
Morfolinas/química , Inibidores de Proteínas Quinases/química , Sulfonas/química , Serina-Treonina Quinases TOR/antagonistas & inibidores , Animais , Sítios de Ligação , Simulação por Computador , Meia-Vida , Humanos , Microssomos Hepáticos/metabolismo , Morfolinas/síntese química , Morfolinas/farmacocinética , Fosfatidilinositol 3-Quinases/metabolismo , Inibidores de Fosfoinositídeo-3 Quinase , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/farmacocinética , Estrutura Terciária de Proteína , Ratos , Relação Estrutura-Atividade , Sulfonas/síntese química , Sulfonas/farmacocinética , Serina-Treonina Quinases TOR/metabolismo
18.
J Med Chem ; 54(24): 8490-500, 2011 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-22040023

RESUMO

Analogues substituted with various amines at the 6-position of the pyrazine ring on (4-amino-7-isopropyl-7H-pyrrolo[2,3-d]pyrimidin-5-yl)pyrazin-2-ylmethanone were discovered as potent and selective inhibitors of PDK1 with potential as anticancer agents. An early lead with 2-pyridine-3-ylethylamine as the pyrazine substituent showed moderate potency and selectivity. Structure-based drug design led to improved potency and selectivity against PI3Kα through a combination of cyclizing the ethylene spacer into a saturated, five-membered ring and substituting on the 4-position of the aryl ring with a fluorine. ADME properties were improved by lowering the lipophilicity with heteroatom replacements in the saturated, five-membered ring. The optimized analogues have a PDK1 Ki of 1 nM and >100-fold selectivity against PI3K/AKT-pathway kinases. The cellular potency of these analogues was assessed by the inhibition of AKT phosphorylation (T308) and by their antiproliferation activity against a number of tumor cell lines.


Assuntos
Antineoplásicos/síntese química , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Piridinas/síntese química , Pirróis/síntese química , Proteínas Quinases Dependentes de 3-Fosfoinositídeo , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Cristalografia por Raios X , Ensaios de Seleção de Medicamentos Antitumorais , Etilaminas/síntese química , Etilaminas/química , Etilaminas/farmacologia , Humanos , Modelos Moleculares , Fosforilação , Conformação Proteica , Proteínas Proto-Oncogênicas c-akt/metabolismo , Piridinas/química , Piridinas/farmacologia , Pirróis/química , Pirróis/farmacologia , Transdução de Sinais , Relação Estrutura-Atividade
19.
Cancer Res ; 71(17): 5838-49, 2011 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-21737488

RESUMO

Small-molecule inhibitors of Hsp90 show promise in the treatment of castrate-resistant prostate cancer (CRPC); however, these inhibitors trigger a heat shock response that attenuates drug effectiveness. Attenuation is associated with increased expression of Hsp90, Hsp70, Hsp27, and clusterin (CLU) that mediate tumor cell survival and treatment resistance. We hypothesized that preventing CLU induction in this response would enhance Hsp90 inhibitor-induced CRPC cell death in vitro and in vivo. To test this hypothesis, we treated CRPC with the Hsp90 inhibitor PF-04929113 or 17-AAG in the absence or presence of OGX-011, an antisense drug that targets CLU. Treatment with either Hsp90 inhibitor alone increased nuclear translocation and transcriptional activity of the heat shock factor HSF-1, which stimulated dose- and time-dependent increases in HSP expression, especially CLU expression. Treatment-induced increases in CLU were blocked by OGX-011, which synergistically enhanced the activity of Hsp90 inhibition on CRPC cell growth and apoptosis. Accompanying these effects was a decrease in HSF-1 transcriptional activity as well as expression of HSPs, Akt, prostate-specific antigen, and androgen receptor. In vivo evaluation of the Hsp90 inhibitors with OGX-011 in xenograft models of human CRPC showed that OGX-011 markedly potentiated antitumor efficacy, leading to an 80% inhibition of tumor growth with prolonged survival compared with Hsp90 inhibitor monotherapy. Together, our findings indicate that Hsp90 inhibitor-induced activation of the heat shock response and CLU is attenuated by OGX-011, with synergistic effects on delaying CRPC progression.


Assuntos
Benzamidas/uso terapêutico , Benzoquinonas/uso terapêutico , Clusterina/antagonistas & inibidores , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Resposta ao Choque Térmico/efeitos dos fármacos , Indazóis/uso terapêutico , Lactamas Macrocíclicas/uso terapêutico , Neoplasias da Próstata/tratamento farmacológico , Tionucleotídeos/uso terapêutico , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Clusterina/genética , Sinergismo Farmacológico , Glicina , Resposta ao Choque Térmico/genética , Humanos , Masculino , Camundongos , Camundongos Nus , Neoplasias da Próstata/patologia , Ensaios Antitumorais Modelo de Xenoenxerto
20.
Clin Cancer Res ; 17(16): 5432-42, 2011 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-21715568

RESUMO

PURPOSE: Triple-negative breast cancer (TNBC) patients have poor prognoses and survival outcomes such that the development of new targeted therapies is in strong demand. Mechanisms associated with high proliferation and aggressive tumor progression, such as PI3K/PTEN aberration, epidermal growth factor receptor (EGFR) overexpression, and cell-cycle upregulation, play important roles in TNBC. The molecular chaperone Hsp90 is required for the conformational maturation and stability of a variety of proteins in multiple pathways, such as EGFR, AKT, Raf, cdk4, etc. Therefore, an Hsp90 inhibitor may show therapeutic benefit in TNBC by targeting multiple pathways. EXPERIMENTAL DESIGN: The novel oral Hsp90 inhibitor PF-4942847 was characterized in multiple in vitro and in vivo assays to determine its antitumor activity in TNBC cell lines. In addition, the correlation of AKT degradation and Hsp70 induction in host peripheral blood lymphocytes (PBL) and xenograft tumors was determined. RESULTS: PF-4942847 induces degradation of multiple client proteins, cell-cycle block, apoptosis, and inhibits cell proliferation in TNBC lines, subsequently leading to tumor growth inhibition in mouse xenograft models. The correlation of AKT degradation and Hsp70 induction between PBLs and xenograft tumors reveals a differential modulation of Hsp90 activity between host and tumor tissues, and suggests that AKT degradation in PBLs may serve as a pharmacodynamic biomarker in future clinical development. CONCLUSIONS: The novel oral Hsp90 inhibitor, PF-4942847, is a candidate for clinical development in TNBC by collaboratively targeting multiple signaling pathways. In addition, AKT degradation in PBLs may serve as a biomarker in clinical development.


Assuntos
Antineoplásicos/farmacologia , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Compostos Heterocíclicos de 4 ou mais Anéis/farmacologia , Neoplasias Mamárias Experimentais/tratamento farmacológico , Ensaios Antitumorais Modelo de Xenoenxerto , Administração Oral , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Feminino , Proteínas de Choque Térmico HSP90/metabolismo , Compostos Heterocíclicos de 4 ou mais Anéis/administração & dosagem , Compostos Heterocíclicos de 4 ou mais Anéis/química , Humanos , Immunoblotting , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/metabolismo , Neoplasias Mamárias Experimentais/metabolismo , Neoplasias Mamárias Experimentais/patologia , Camundongos , Camundongos Nus , Camundongos SCID , Estrutura Molecular , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptor ErbB-2/metabolismo , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Transdução de Sinais/efeitos dos fármacos , Carga Tumoral/efeitos dos fármacos
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