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1.
Neoplasia ; 55: 101020, 2024 09.
Artigo em Inglês | MEDLINE | ID: mdl-38991376

RESUMO

The 78-kDa glucose regulated protein (GRP78) commonly upregulated in a wide variety of tumors is an important prognostic marker and a promising target for suppressing tumorigenesis and treatment resistance. While GRP78 is well established as a major endoplasmic reticulum (ER) chaperone with anti-apoptotic properties and a master regulator of the unfolded protein response, its new role as a regulator of oncoprotein expression is just emerging. MYC is dysregulated in about 70 % of human cancers and is the most commonly activated oncoprotein. However, despite recent advances, therapeutic targeting of MYC remains challenging. Here we identify GRP78 as a new target for suppression of MYC expression. Using multiple MYC-dependent cancer models including head and neck squamous cell carcinoma and their cisplatin-resistant clones, breast and pancreatic adenocarcinoma, our studies revealed that GRP78 knockdown by siRNA or inhibition of its activity by small molecule inhibitors (YUM70 or HA15) reduced c-MYC expression, leading to onset of apoptosis and loss of cell viability. This was observed in 2D cell culture, 3D spheroid and in xenograft models. Mechanistically, we determined that the suppression of c-MYC is at the post-transcriptional level and that YUM70 and HA15 treatment potently upregulated the eukaryotic translation inhibitor 4E-BP1, which targets eIF4E critical for c-MYC translation initiation. Furthermore, knock-down of 4E-BP1 via siRNA rescued YUM70-mediated c-MYC suppression. As YUM70 is also capable of suppressing N-MYC expression, this study offers a new approach to suppress MYC protein expression through knockdown or inhibition of GRP78.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Proteínas de Ciclo Celular , Chaperona BiP do Retículo Endoplasmático , Regulação Neoplásica da Expressão Gênica , Proteínas de Choque Térmico , Proteínas Proto-Oncogênicas c-myc , Humanos , Chaperona BiP do Retículo Endoplasmático/metabolismo , Proteínas Proto-Oncogênicas c-myc/metabolismo , Proteínas Proto-Oncogênicas c-myc/genética , Animais , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Proteínas de Choque Térmico/antagonistas & inibidores , Camundongos , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/antagonistas & inibidores , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Proteínas de Ciclo Celular/antagonistas & inibidores , Fosfoproteínas/metabolismo , Fosfoproteínas/genética , Fosfoproteínas/antagonistas & inibidores , Apoptose/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto , Neoplasias/genética , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Neoplasias/patologia , Regulação para Cima/efeitos dos fármacos
2.
AORN J ; 118(6): 391-403, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-38011055

RESUMO

Traditional use of opioids to treat postoperative pain may lead to abuse and overdose. The development of Enhanced Recovery After Surgery (ERAS) protocols has helped to shift pain management from traditional methods to evidence-based best practices involving multimodal analgesia techniques. The purpose of this quality improvement project was to implement and determine the effectiveness of a standardized, evidence-based ERAS pain management pathway for patients undergoing colorectal or gynecology procedures at a medical center in Hawaii. After the intervention, the evaluation of data associated with opioid use, patients' pain scores, time spent in the postanesthesia care unit, and inpatient length of stay showed that most results were not significant. However, the ERAS pain management pathway did reduce clinical practice variations, intraoperative opioid administration, the time that patients spent in the postanesthesia care unit, and length of stay. The ERAS pain management pathway continues to be used and updated at this facility.


Assuntos
Recuperação Pós-Cirúrgica Melhorada , Manejo da Dor , Humanos , Manejo da Dor/métodos , Havaí , Analgésicos Opioides/uso terapêutico , Dor Pós-Operatória/tratamento farmacológico , Estudos Retrospectivos , Tempo de Internação
3.
Proc Natl Acad Sci U S A ; 120(31): e2303448120, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37487081

RESUMO

Cancer cells are commonly subjected to endoplasmic reticulum (ER) stress. To gain survival advantage, cancer cells exploit the adaptive aspects of the unfolded protein response such as upregulation of the ER luminal chaperone GRP78. The finding that when overexpressed, GRP78 can escape to other cellular compartments to gain new functions regulating homeostasis and tumorigenesis represents a paradigm shift. Here, toward deciphering the mechanisms whereby GRP78 knockdown suppresses EGFR transcription, we find that nuclear GRP78 is prominent in cancer and stressed cells and uncover a nuclear localization signal critical for its translocation and nuclear activity. Furthermore, nuclear GRP78 can regulate expression of genes and pathways, notably those important for cell migration and invasion, by interacting with and inhibiting the activity of the transcriptional repressor ID2. Our study reveals a mechanism for cancer cells to respond to ER stress via transcriptional regulation mediated by nuclear GRP78 to adopt an invasive phenotype.


Assuntos
Núcleo Celular , Chaperona BiP do Retículo Endoplasmático , Humanos , Carcinogênese , Movimento Celular , Transformação Celular Neoplásica
4.
Neoplasia ; 33: 100837, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36162331

RESUMO

KRAS is the most commonly mutated oncogene in human cancers with limited therapeutic options, thus there is a critical need to identify novel targets and inhibiting agents. The 78-kDa glucose-regulated protein GRP78, which is upregulated in KRAS cancers, is an essential chaperone and the master regulator of the unfolded protein response (UPR). Following up on our recent discoveries that GRP78 haploinsufficiency suppresses both KRASG12D-driven pancreatic and lung tumorigenesis, we seek to determine the underlying mechanisms. Here, we report that knockdown of GRP78 via siRNA reduced oncogenic KRAS protein level in human lung, colon, and pancreatic cancer cells bearing various KRAS mutations. This effect was at the post-transcriptional level and is independent of proteasomal degradation or autophagy. Moreover, targeting GRP78 via small molecule inhibitors such as HA15 and YUM70 with anti-cancer activities while sparing normal cells significantly suppressed oncogenic KRAS expression in vitro and in vivo, associating with onset of apoptosis and loss of viability in cancer cells bearing various KRAS mutations. Collectively, our studies reveal that GRP78 is a previously unidentified regulator of oncogenic KRAS expression, and, as such, augments the other anti-cancer activities of GRP78 small molecule inhibitors to potentially achieve general, long-term suppression of mutant KRAS-driven tumorigenesis.


Assuntos
Chaperona BiP do Retículo Endoplasmático , Proteínas Proto-Oncogênicas p21(ras) , Carcinogênese , Linhagem Celular Tumoral , Transformação Celular Neoplásica/genética , Glucose , Humanos , Mutação , Proteínas Proto-Oncogênicas p21(ras)/genética , RNA Interferente Pequeno
5.
Biomacromolecules ; 23(8): 3116-3129, 2022 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-35786858

RESUMO

Rapalogues are powerful therapeutic modalities for breast cancer; however, they suffer from low solubility and dose-limiting side effects. To overcome these challenges, we developed a long-circulating multiheaded drug carrier called 5FA, which contains rapamycin-binding domains linked with elastin-like polypeptides (ELPs). To target these "Hydra-ELPs" toward breast cancer, we here linked 5FA with four distinct peptides which are reported to engage the cell surface form of the 78 kDa glucose-regulated protein (csGRP78). To determine if these peptides affected the carrier solubility, this library was characterized by light scattering and mass spectrometry. To guide in vitro selection of the most potent functional carrier for rapamycin, its uptake and inhibition of mTORC1 were monitored in a ductal breast cancer model (BT474). Using flow cytometry to track cellular association, it was found that only the targeted carriers enhanced cellular uptake and were susceptible to proteolysis by SubA, which specifically targets csGRP78. The functional inhibition of mTOR was monitored by Western blot for pS6K, whereby the best carrier L-5FA reduced mTOR activity by 3-fold compared to 5FA or free rapamycin. L-5FA was further visualized using super-resolution confocal laser scanning microscopy, which revealed that targeting increased exposure to the carrier by ∼8-fold. This study demonstrates how peptide ligands for GRP78, such as the L peptide (RLLDTNRPLLPY), may be incorporated into protein-based drug carriers to enhance targeting.


Assuntos
Neoplasias da Mama , Hydra , Animais , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Portadores de Fármacos/química , Elastina/química , Chaperona BiP do Retículo Endoplasmático , Feminino , Humanos , Hydra/metabolismo , Peptídeos/química , Sirolimo/química , Sirolimo/farmacologia , Serina-Treonina Quinases TOR/uso terapêutico
6.
J Mol Biol ; 434(10): 167564, 2022 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-35358571

RESUMO

Translation factors are essential for regulation of protein synthesis. The eukaryotic translation initiation factor 5A (eIF5A) family is made up of two paralogues - eIF5A1 and eIF5A2 - which display high sequence homology but distinct tissue tropism. While eIF5A1 directly binds to the ribosome and regulates translation initiation, elongation, and termination, the molecular function of eIF5A2 remains poorly understood. Here, we engineer an eIF5A2 knockout allele in the SW480 colon cancer cell line. Using ribosome profiling and RNA-Sequencing, we reveal that eIF5A2 is functionally distinct from eIF5A1 and does not regulate transcript-specific or global protein synthesis. Instead, eIF5A2 knockout leads to decreased intrinsic antiviral gene expression, including members of the IFITM and APOBEC3 family. Furthermore, cells lacking eIF5A2 display increased permissiveness to virus infection. Our results uncover eIF5A2 as a factor involved regulating the antiviral transcriptome, and reveal an example of how gene duplications of translation factors can result in proteins with distinct functions.


Assuntos
Fator de Iniciação 5 em Eucariotos , Regulação da Expressão Gênica , Fatores de Iniciação de Peptídeos , Proteínas de Ligação a RNA , Viroses , Desaminases APOBEC/genética , Linhagem Celular Tumoral , Fator de Iniciação 5 em Eucariotos/genética , Fator de Iniciação 5 em Eucariotos/metabolismo , Técnicas de Inativação de Genes , Humanos , Fatores de Iniciação de Peptídeos/genética , Fatores de Iniciação de Peptídeos/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Transcriptoma , Viroses/genética , Fator de Iniciação de Tradução Eucariótico 5A
7.
Front Oncol ; 12: 1044699, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36713577

RESUMO

Background: Head and neck squamous cell carcinoma (HNSCC) is one of the leading causes of cancer-related death worldwide. Surgical resection, radiation and chemotherapy are the mainstay of HNSCC treatment but are often unsatisfactory. Cisplatin is a commonly used chemotherapy in HNSCC; however, cisplatin resistance is a major cause of relapse and death. The 78-kD glucose-regulated protein (GRP78) is the master regulator of the unfolded protein response (UPR) and is implicated in therapeutic resistance in cancer. The role of GRP78 in cisplatin resistance in HNSCC remains unclear. YUM70 is a newly discovered hydroxyquinoline analogue and found to be an inhibitor of GRP78. The effect of YUM70 in HNSCC cell lines is unknown. Method: Knockdown of GRP78 by siRNAs was performed to investigate the effect of GRP78 reduction in endoplasmic reticulum (ER)-stress induced and general apoptosis. Western blots examining apoptotic markers were performed on three HPV-negative HNSCC cell lines. WST-1 assay was performed to determine cell viability. In reverse, we utilized AA147, an ER proteostasis regulator to upregulate GRP78, and apoptotic markers and cell viability were determined. To test the ability of YUM70 to reverse cisplatin resistance, cisplatin-resistant HNSCC cell lines were generated by prolonged, repeated exposure to increasing concentrations of cisplatin. Colony formation assay using the cisplatin-resistant HNSCC cell line was performed to assess the in vitro reproductive cell survival. Furthermore, to test the ability of YUM70 to reverse cisplatin resistance in a physiologically relevant system, we subjected the 3D spheroids of the cisplatin-resistant HNSCC cell line to cisplatin treatment with or without YUM70 and monitored the onset of apoptosis. Results: Reduction of GRP78 level induced HNSCC cell death while GRP78 upregulation conferred higher resistance to cisplatin. Combined cisplatin and YUM70 treatment increased apoptotic markers in the cisplatin-resistant HNSCC cell line, associating with reduced cell viability and clonogenicity. The combination treatment also increased apoptotic markers in the 3D spheroid model. Conclusion: The GRP78 inhibitor YUM70 reduced HNSCC cell viability and re-sensitized cisplatin-resistant HNSCC cell line in both 2D and 3D spheroid models, suggesting the potential use of YUM70 in the treatment of HNSCC, including cisplatin-resistant HNSCC.

8.
Neoplasia ; 23(12): 1213-1226, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34768108

RESUMO

The 78 kilodalton glucose-regulated protein (GRP78) is a major endoplasmic reticulum (ER) molecular chaperone with antiapoptotic properties and a key regulator of the unfolded protein response (UPR). ER-stress induction of GRP78 in cancer cells represents a major pro-survival branch of the UPR. Pancreatic ductal adenocarcinoma (PDAC) remains a highly lethal disease and high level of GRP78 is associated with aggressive disease and poor survival. Recently, we reported that PDAC exhibited high level of ER stress and that GRP78 haploinsufficiency is sufficient to suppress pancreatic tumorigenesis in mice, suggesting the utility of inhibitors of GRP78 expression in combating pancreatic cancer. Screening of clinically relevant compound libraries revealed that cardiac glycosides (CGs) can inhibit ER-stress induction of GRP78 in pancreatic and other types of human cancers. Using the FDA-approved CG compound Lanatoside C (LanC) and human pancreatic cancer cell lines as model systems, we discovered that LanC preferably suppressed ER stress induction of GRP78 and to a lesser extent GRP94. The suppression is at the post-transcriptional level and dependent on the Na+/K+-ATPase ion pump. Overexpression of GRP78 mitigates apoptotic activities of LanC in ER stressed cells. Our study revealed a new function of CGs as inhibitor of stress induction of GRP78, and that this suppression at least in part contributes to the apoptotic activities of CGs in human pancreatic cancer cells in vitro. These findings support further investigation into CGs as potential antineoplastic agents for pancreatic and other cancers which depend on GRP78 for growth and survival.


Assuntos
Carcinoma Ductal Pancreático/metabolismo , Chaperona BiP do Retículo Endoplasmático/efeitos dos fármacos , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Lanatosídeos/farmacologia , Neoplasias Pancreáticas/metabolismo , Glicosídeos Cardíacos/farmacologia , Linhagem Celular Tumoral , Chaperona BiP do Retículo Endoplasmático/metabolismo , Humanos , Resposta a Proteínas não Dobradas/efeitos dos fármacos , Neoplasias Pancreáticas
9.
Nature ; 597(7874): 109-113, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34261127

RESUMO

Cyclic GMP-AMP synthase (cGAS) is a cytosolic DNA sensor that produces the second messenger cG[2'-5']pA[3'-5']p (2'3'-cGAMP) and controls activation of innate immunity in mammalian cells1-5. Animal genomes typically encode multiple proteins with predicted homology to cGAS6-10, but the function of these uncharacterized enzymes is unknown. Here we show that cGAS-like receptors (cGLRs) are innate immune sensors that are capable of recognizing divergent molecular patterns and catalysing synthesis of distinct nucleotide second messenger signals. Crystal structures of human and insect cGLRs reveal a nucleotidyltransferase signalling core shared with cGAS and a diversified primary ligand-binding surface modified with notable insertions and deletions. We demonstrate that surface remodelling of cGLRs enables altered ligand specificity and used a forward biochemical screen to identify cGLR1 as a double-stranded RNA sensor in the model organism Drosophila melanogaster. We show that RNA recognition activates Drosophila cGLR1 to synthesize the novel product cG[3'-5']pA[2'-5']p (3'2'-cGAMP). A crystal structure of Drosophila stimulator of interferon genes (dSTING) in complex with 3'2'-cGAMP explains selective isomer recognition, and 3'2'-cGAMP induces an enhanced antiviral state in vivo that protects from viral infection. Similar to radiation of Toll-like receptors in pathogen immunity, our results establish cGLRs as a diverse family of metazoan pattern recognition receptors.


Assuntos
Drosophila melanogaster/metabolismo , Nucleotídeos Cíclicos/metabolismo , Nucleotidiltransferases/metabolismo , RNA de Cadeia Dupla/metabolismo , Receptores de Reconhecimento de Padrão/metabolismo , Sistemas do Segundo Mensageiro , Sequência de Aminoácidos , Animais , Cristalografia por Raios X , Proteínas de Drosophila/química , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/imunologia , Drosophila melanogaster/virologia , Feminino , Humanos , Imunidade Inata , Masculino , Proteínas de Membrana/química , Proteínas de Membrana/metabolismo , Modelos Moleculares , Nucleotidiltransferases/química , Nucleotidiltransferases/imunologia , RNA de Cadeia Dupla/análise , RNA de Cadeia Dupla/imunologia , Receptores de Reconhecimento de Padrão/química , Receptores de Reconhecimento de Padrão/imunologia , Vírus/imunologia
10.
Cell Mol Life Sci ; 78(12): 5179-5195, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33974094

RESUMO

Despite new advances on the functions of ER chaperones at the cell surface, the translocation mechanisms whereby these chaperones can escape from the ER to the cell surface are just emerging. Previously we reported that in many cancer types, upon ER stress, IRE1α binds to and triggers SRC activation resulting in KDEL receptor dispersion from the Golgi and suppression of retrograde transport. In this study, using a combination of molecular, biochemical, and imaging approaches, we discovered that in colon and lung cancer, upon ER stress, ER chaperones, such as GRP78 bypass the Golgi and unconventionally traffic to the cell surface via endosomal transport mediated by Rab GTPases (Rab4, 11 and 15). Such unconventional transport is driven by membrane fusion between ER-derived vesicles and endosomes requiring the v-SNARE BET1 and t-SNARE Syntaxin 13. Furthermore, GRP78 loading into ER-derived vesicles requires the co-chaperone DNAJC3 that is regulated by ER-stress induced PERK-AKT-mTOR signaling.


Assuntos
Membrana Celular/metabolismo , Neoplasias do Colo/metabolismo , Retículo Endoplasmático/metabolismo , Complexo de Golgi/metabolismo , Proteínas de Choque Térmico/metabolismo , Neoplasias Pulmonares/metabolismo , Neoplasias do Colo/genética , Neoplasias do Colo/patologia , Chaperona BiP do Retículo Endoplasmático , Proteínas de Choque Térmico/genética , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Mutagênese Sítio-Dirigida , Mutação , Transporte Proteico , Transdução de Sinais , Células Tumorais Cultivadas
11.
Oncogene ; 40(20): 3624-3632, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33931739

RESUMO

Lung cancer is the leading cause of cancer mortality worldwide and KRAS is the most commonly mutated gene in lung adenocarcinoma (LUAD). The 78-kDa glucose-regulated protein GRP78/BiP is a key endoplasmic reticulum chaperone protein and a major pro-survival effector of the unfolded protein response (UPR). Analysis of the Cancer Genome Atlas database and immunostain of patient tissues revealed that compared to normal lung, GRP78 expression is generally elevated in human lung cancers, including tumors bearing the KRASG12D mutation. To test the requirement of GRP78 in human lung oncogenesis, we generated mouse models containing floxed Grp78 and Kras Lox-Stop-Lox G12D (KrasLSL-G12D) alleles. Simultaneous activation of the KrasG12D allele and knockout of the Grp78 alleles were achieved in the whole lung or selectively in lung alveolar epithelial type 2 cells known to be precursors for adenomas that progress to LUAD. Here we report that GRP78 haploinsufficiency is sufficient to suppress KrasG12D-mediated lung tumor progression and prolong survival. Furthermore, GRP78 knockdown in human lung cancer cell line A427 (KrasG12D/+) leads to activation of UPR and apoptotic markers and loss of cell viability. Our studies provide evidence that targeting GRP78 represents a novel therapeutic approach to suppress mutant KRAS-mediated lung tumorigenesis.


Assuntos
Chaperona BiP do Retículo Endoplasmático/metabolismo , Neoplasias Pulmonares/patologia , Mutação , Proteínas Proto-Oncogênicas p21(ras)/genética , Resposta a Proteínas não Dobradas , Animais , Linhagem Celular Tumoral , Modelos Animais de Doenças , Progressão da Doença , Chaperona BiP do Retículo Endoplasmático/genética , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Transdução de Sinais
12.
Cancer Res ; 81(7): 1883-1895, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33531374

RESUMO

GRP78 (glucose-regulated protein, 78 kDa) is a key regulator of endoplasmic reticulum (ER) stress signaling. Cancer cells are highly proliferative and have high demand for protein synthesis and folding, which results in significant stress on the ER. To respond to ER stress and maintain cellular homeostasis, cells activate the unfolded protein response (UPR) that promotes either survival or apoptotic death. Cancer cells utilize the UPR to promote survival and growth. In this study, we describe the discovery of a series of novel hydroxyquinoline GRP78 inhibitors. A representative analogue, YUM70, inhibited pancreatic cancer cell growth in vitro and showed in vivo efficacy in a pancreatic cancer xenograft model with no toxicity to normal tissues. YUM70 directly bound GRP78 and inactivated its function, resulting in ER stress-mediated apoptosis. A YUM70 analogue conjugated with BODIPY showed colocalization of the compound with GRP78 in the ER. Moreover, a YUM70-PROTAC (proteolysis targeting chimera) was synthesized to force degradation of GRP78 in pancreatic cancer cells. YUM70 showed a strong synergistic cytotoxicity with topotecan and vorinostat. Together, our study demonstrates that YUM70 is a novel inducer of ER stress, with preclinical efficacy as a monotherapy or in combination with topoisomerase and HDAC inhibitors in pancreatic cancer. SIGNIFICANCE: This study identifies a novel ER stress inducer that binds GRP78 and inhibits pancreatic cancer cell growth in vitro and in vivo, demonstrating its potential as a therapeutic agent for pancreatic cancer.


Assuntos
Apoptose/efeitos dos fármacos , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Proteínas de Choque Térmico/antagonistas & inibidores , Hidroxiquinolinas/farmacologia , Neoplasias Pancreáticas/patologia , Células A549 , Animais , Linhagem Celular Tumoral , Chaperona BiP do Retículo Endoplasmático , Feminino , Células HCT116 , Células HT29 , Humanos , Hidroxiquinolinas/uso terapêutico , Células MCF-7 , Camundongos , Camundongos Nus , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/metabolismo , Resposta a Proteínas não Dobradas/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto , Neoplasias Pancreáticas
13.
J Natl Black Nurses Assoc ; 32(2): 28-36, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35338802

RESUMO

Cervical cancer, one of the most common gynecological cancers in the United States, is highly preventable due to the papanicoloau (Pap) test with human papillomavirus (HPV) co-screening. However, there is increasing evidence of low adherence to screening guidelines by health care providers (HCP). The purpose of this study was to identify and improve health care providers' attitudes, beliefs, and knowledge of the most updated screening guidelines and to provide them with an evidence-based educational intervention to increase their confidence in the updated guidelines, improve their attitudes and beliefs, and screen their patients more appropriately. Before being presented with an intervention consisting of an educational session that detailed the most recent U.S. Preventative Services Task Force (USPSTF) cervical cancer screening guidelines, the HCPs were surveyed for knowledge and at 2 months post-intervention, they were surveyed again. When the survey was scored pre- and post-intervention, two-thirds of the HCPs improved their score. An important barrier (67% post-intervention) to extending the interval included concerns about the patients losing contact with the medical system (50% at baseline). An educational intervention, including the updated screening guidelines, improved the HCPs' attitudes, beliefs, and knowledge of screening guidelines.


Assuntos
Neoplasias do Colo do Útero , Detecção Precoce de Câncer , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Programas de Rastreamento , Melhoria de Qualidade , Estados Unidos , Neoplasias do Colo do Útero/diagnóstico
14.
Am J Respir Crit Care Med ; 201(2): 198-211, 2020 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-31738079

RESUMO

Rationale: Alveolar epithelial cell (AEC) injury and dysregulated repair are implicated in the pathogenesis of pulmonary fibrosis. Endoplasmic reticulum (ER) stress in AEC has been observed in idiopathic pulmonary fibrosis (IPF), a disease of aging.Objectives: To investigate a causal role for ER stress in the pathogenesis of pulmonary fibrosis (PF) and therapeutic potential of ER stress inhibition in PF.Methods: The role of ER stress in AEC dysfunction and fibrosis was studied in mice with tamoxifen (Tmx)-inducible deletion of ER chaperone Grp78, a key regulator of ER homeostasis, in alveolar type II (AT2) cells, progenitors of distal lung epithelium, and in IPF lung slice cultures.Measurements and Main Results:Grp78 deletion caused weight loss, mortality, lung inflammation, and spatially heterogeneous fibrosis characterized by fibroblastic foci, hyperplastic AT2 cells, and increased susceptibility of old and male mice, all features of IPF. Fibrosis was more persistent in more severely injured Grp78 knockout (KO) mice. Grp78 KO AT2 cells showed evidence of ER stress, apoptosis, senescence, impaired progenitor capacity, and activation of TGF-ß (transforming growth factor-ß)/SMAD signaling. Glucose-regulated protein 78 is reduced in AT2 cells from old mice and patients with IPF, and ER stress inhibitor tauroursodeoxycholic acid ameliorates ER stress and fibrosis in Grp78 KO mouse and IPF lung slice cultures.Conclusions: These results support a causal role for ER stress and resulting epithelial dysfunction in PF and suggest ER stress as a potential mechanism linking aging to IPF. Modulation of ER stress and chaperone function may offer a promising therapeutic approach for pulmonary fibrosis.


Assuntos
Células Epiteliais Alveolares/metabolismo , Estresse do Retículo Endoplasmático/genética , Proteínas de Choque Térmico/genética , Fibrose Pulmonar/genética , Células-Tronco/metabolismo , Fatores Etários , Células Epiteliais Alveolares/patologia , Clorometilcetonas de Aminoácidos/farmacologia , Animais , Antioxidantes/farmacologia , Apoptose/genética , Senescência Celular/genética , Dasatinibe/farmacologia , Chaperona BiP do Retículo Endoplasmático , Técnicas de Inativação de Genes , Proteínas de Choque Térmico/metabolismo , Humanos , Fibrose Pulmonar Idiopática/metabolismo , Pulmão/efeitos dos fármacos , Glicoproteínas de Membrana/efeitos dos fármacos , Glicoproteínas de Membrana/metabolismo , Camundongos , Camundongos Knockout , Inibidores de Proteínas Quinases/farmacologia , Fibrose Pulmonar/metabolismo , Fibrose Pulmonar/patologia , Quercetina/farmacologia , Quinolinas/farmacologia , Proteínas Smad/metabolismo , Ácido Tauroquenodesoxicólico/farmacologia , Fator de Transcrição CHOP/efeitos dos fármacos , Fator de Transcrição CHOP/metabolismo , Fator de Crescimento Transformador beta/metabolismo
15.
Life Sci Alliance ; 2(4)2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31416894

RESUMO

GRP78 conducts protein folding and quality control in the ER and shows elevated expression and cell surface translocation in advanced tumors. However, the underlying mechanisms enabling GRP78 to exert novel signaling functions at cell surface are just emerging. CD44 is a transmembrane protein and an important regulator of cancer metastasis, and isoform switch of CD44 through incorporating additional variable exons to the extracellular juxtamembrane region is frequently observed during cancer progression. Using super-resolution dual-color single-particle tracking, we report that GRP78 interacts with CD44v in plasma membrane nanodomains of breast cancer cells. We further show that targeting cell surface GRP78 by the antibodies can effectively reduce cell surface expression of CD44v and cell spreading of tamoxifen-resistant breast cancer cells. Our results uncover new functions of GRP78 as an interacting partner of CD44v and as a regulator of CD44v membrane homeostasis and cell spreading. This study also provides new insights into anti-CD44 therapy in tamoxifen-resistant breast cancer.


Assuntos
Neoplasias da Mama/metabolismo , Resistencia a Medicamentos Antineoplásicos , Proteínas de Choque Térmico/metabolismo , Receptores de Hialuronatos/metabolismo , Actinas/metabolismo , Membrana Celular/metabolismo , Chaperona BiP do Retículo Endoplasmático , Feminino , Regulação Neoplásica da Expressão Gênica , Homeostase , Humanos , Receptores de Hialuronatos/química , Células MCF-7 , Células Neoplásicas Circulantes/metabolismo , Transdução de Sinais , Tamoxifeno
16.
Neoplasia ; 21(8): 837-848, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31306849

RESUMO

Translocation of 78-kDa glucose-regulated protein (GRP78) from endoplasmic reticulum (ER) to plasma membrane represents a paradigm shift beyond its traditional function as an ER chaperone protein. Cell surface GRP78 (csGRP78) exerts novel signaling functions, and mechanisms underlying its cell surface expression are just emerging. Acquired tamoxifen resistance of breast cancer cells is accompanied with elevated level of csGRP78. Therefore, the tamoxifen-resistant MCF7 breast cancer cells (MCF7-LR) represents a clinically relevant model to study mechanisms of csGRP78 expression. We discovered that a proline-rich region (PRR) containing three consecutive prolines close to the COOH-terminus of GRP78 is important for its ability to form a complex with the partner protein, CD44v, as demonstrated by in vitro glutathione S-transferase pull-down assay. Proline to alanine mutations at the PRR compromised GRP78 expression level on the cell surface as evidenced by purification of biotinylated cell surface proteins. Reconstitution of MCF7-LR cells with the PRR mutant after knockdown of endogenous GRP78 diminished the capacity of GRP78 to stimulate STAT3 activation. The enforced expression of a short peptide bearing the PRR region of GRP78 led to reduction of CD44v and Cyclin D1 protein levels as well as cell viability, accompanied with increase in apoptotic signaling including cleaved Caspase-3 and PARP. These findings suggest that the COOH-terminal PRR of GRP78 is critical for its interaction with CD44v as well as its cell surface expression, and enforced expression of the short peptide bearing the PRR region may provide a new approach to lower the viability of tamoxifen-resistant breast cancer cells.


Assuntos
Membrana Celular/metabolismo , Resistencia a Medicamentos Antineoplásicos/genética , Expressão Gênica , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Domínios Proteicos Ricos em Prolina , Domínios e Motivos de Interação entre Proteínas , Tamoxifeno/farmacologia , Sequência de Aminoácidos , Apoptose/efeitos dos fármacos , Apoptose/genética , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular , Retículo Endoplasmático/metabolismo , Chaperona BiP do Retículo Endoplasmático , Feminino , Proteínas de Choque Térmico/química , Humanos , Receptores de Hialuronatos/química , Receptores de Hialuronatos/metabolismo , Células MCF-7 , Modelos Moleculares , Ligação Proteica , Conformação Proteica , Transporte Proteico , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais
17.
Nucleic Acids Res ; 47(15): 8163-8179, 2019 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-31287876

RESUMO

Type II topoisomerases catalyze essential DNA transactions and are proven drug targets. Drug discrimination by prokaryotic and eukaryotic topoisomerases is vital to therapeutic utility, but is poorly understood. We developed a next-generation sequencing (NGS) approach to identify drug-resistance mutations in eukaryotic topoisomerases. We show that alterations conferring resistance to poisons of human and yeast topoisomerase II derive from a rich mutational 'landscape' of amino acid substitutions broadly distributed throughout the entire enzyme. Both general and discriminatory drug-resistant behaviors are found to arise from different point mutations found at the same amino acid position and to occur far outside known drug-binding sites. Studies of selected resistant enzymes confirm the NGS data and further show that the anti-cancer quinolone vosaroxin acts solely as an intercalating poison, and that the antibacterial ciprofloxacin can poison yeast topoisomerase II. The innate drug-sensitivity of the DNA binding and cleavage region of human and yeast topoisomerases (particularly hTOP2ß) is additionally revealed to be significantly regulated by the enzymes' adenosine triphosphatase regions. Collectively, these studies highlight the utility of using NGS-based methods to rapidly map drug resistance landscapes and reveal that the nucleotide turnover elements of type II topoisomerases impact drug specificity.


Assuntos
Ciprofloxacina/farmacologia , DNA Topoisomerases Tipo II/metabolismo , Naftiridinas/farmacologia , Proteínas de Saccharomyces cerevisiae/metabolismo , Tiazóis/farmacologia , Inibidores da Topoisomerase II/farmacologia , Antibacterianos/farmacologia , Antineoplásicos/farmacologia , DNA/química , DNA/genética , DNA/metabolismo , DNA Topoisomerases Tipo II/química , DNA Topoisomerases Tipo II/genética , Resistência a Medicamentos/efeitos dos fármacos , Resistência a Medicamentos/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Modelos Moleculares , Mutação , Conformação de Ácido Nucleico , Ligação Proteica , Domínios Proteicos , Proteínas de Saccharomyces cerevisiae/antagonistas & inibidores , Proteínas de Saccharomyces cerevisiae/genética
18.
Cell Rep ; 27(4): 1165-1175.e5, 2019 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-31018131

RESUMO

Stimulator of interferon genes (STING) is a key regulator of type I interferon and pro-inflammatory responses during infection, cellular stress, and cancer. Here, we reveal a mechanism for how STING balances activation of IRF3- and NF-κB-dependent transcription and discover that acquisition of discrete signaling modules in the vertebrate STING C-terminal tail (CTT) shapes downstream immunity. As a defining example, we identify a motif appended to the CTT of zebrafish STING that inverts the typical vertebrate signaling response and results in dramatic NF-κB activation and weak IRF3-interferon signaling. We determine a co-crystal structure that explains how this CTT sequence recruits TRAF6 as a new binding partner and demonstrate that the minimal motif is sufficient to reprogram human STING and immune activation in macrophage cells. Together, our results define the STING CTT as a linear signaling hub that can acquire modular motifs to readily adapt downstream immunity.


Assuntos
Imunidade Inata/imunologia , Fator Regulador 3 de Interferon/metabolismo , Interferon Tipo I/metabolismo , Macrófagos/imunologia , Proteínas de Membrana/metabolismo , NF-kappa B/metabolismo , Fator 6 Associado a Receptor de TNF/metabolismo , Animais , Células Cultivadas , Células HEK293 , Humanos , Fator Regulador 3 de Interferon/genética , Macrófagos/metabolismo , Proteínas de Membrana/química , Proteínas de Membrana/genética , Proteínas de Membrana/fisiologia , Camundongos , Camundongos Knockout , NF-kappa B/genética , Conformação Proteica , Especificidade da Espécie , Fator 6 Associado a Receptor de TNF/genética , Peixe-Zebra , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo
19.
Worldviews Evid Based Nurs ; 16(3): 204-210, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31012540

RESUMO

BACKGROUND: Intimate partner violence (IPV) is a significant public health issue. Healthcare providers (e.g., nurses, advanced practice nurses, physicians, social workers) have a unique opportunity to prevent and reduce IPV through screening and referral. The objective of this project was to determine the impact of education and a brief screening tool integrated into the electronic medical record (EMR) on readiness to screen for IPV. METHODS: An intervention was implemented that included the EMR integration of a screening tool, creation of an automated resource telephone system and healthcare provider IPV screening and response education. Readiness for screening was evaluated pre- and postintervention using the Domestic Violence Health Care Provider Survey Scale (DVHCPSS), which is scored cumulatively and by each of six domains. An unpaired Student's t test was performed. RESULTS: Mean age (31-40 years of age) and years of clinical practice (11-15 years) was the same for pre- (n = 96) and postintervention (n = 83) survey respondents. There was an overall significant increase in screening readiness (p = .003) with significant improvement in "professional role resistance/fear of offending the patient" (p < .0001), "blame victim items" (p = .0029), "perceived self-efficacy" (p = .0064), and "victim/provider safety" (p = .003). LINKING EVIDENCE TO ACTION: Adopting and integrating a validated IPV screening tool into the EMR combined with education was associated with an improvement in overall readiness for IPV screening. Reducing and preventing IPV through universal screening and referral can be accomplished by embedding a standardized readily accessible validated IPV screening tool in the EMR.


Assuntos
Pessoal de Saúde/psicologia , Violência por Parceiro Íntimo/estatística & dados numéricos , Programas de Rastreamento/normas , Adulto , Atitude do Pessoal de Saúde , Feminino , Pessoal de Saúde/normas , Humanos , Violência por Parceiro Íntimo/psicologia , Masculino , Programas de Rastreamento/tendências , Pessoa de Meia-Idade , Inquéritos e Questionários
20.
Nature ; 567(7747): 194-199, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30787435

RESUMO

Cyclic dinucleotides (CDNs) have central roles in bacterial homeostasis and virulence by acting as nucleotide second messengers. Bacterial CDNs also elicit immune responses during infection when they are detected by pattern-recognition receptors in animal cells. Here we perform a systematic biochemical screen for bacterial signalling nucleotides and discover a large family of cGAS/DncV-like nucleotidyltransferases (CD-NTases) that use both purine and pyrimidine nucleotides to synthesize a diverse range of CDNs. A series of crystal structures establish CD-NTases as a structurally conserved family and reveal key contacts in the enzyme active-site lid that direct purine or pyrimidine selection. CD-NTase products are not restricted to CDNs and also include an unexpected class of cyclic trinucleotide compounds. Biochemical and cellular analyses of CD-NTase signalling nucleotides demonstrate that these cyclic di- and trinucleotides activate distinct host receptors and thus may modulate the interaction of both pathogens and commensal microbiota with their animal and plant hosts.


Assuntos
Proteínas de Bactérias/metabolismo , Nucleotídeos/biossíntese , Nucleotídeos/metabolismo , Nucleotidiltransferases/química , Nucleotidiltransferases/metabolismo , Animais , Cristalografia por Raios X , Fosfatos de Dinucleosídeos/biossíntese , Fosfatos de Dinucleosídeos/metabolismo , Células HEK293 , Humanos , Camundongos , Nucleotídeos/química , Nucleotidiltransferases/genética , Óperon/genética , Simbiose
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