RESUMO
There is currently no effective treatment for pancreatic ductal adenocarcinoma (PDAC). While palliative chemotherapy offers a survival benefit to most patients, nearly all will eventually progress on treatment and long-term survivability remains poor. Given the lack of subsequent line treatment options, in this study, we sought to identify novel strategies to prevent, delay, or overcome resistance to gemcitabine, one of the most widely used medications in PDAC. Using a combination of single-cell RNA sequencing and high-throughput proteomic analysis, we identified a subset of gemcitabine-resistant tumor cells enriched for calcium/calmodulin signaling. Pharmacologic inhibition of calcium-dependent calmodulin activation led to the rapid loss of drug-resistant phenotypes in vitro, which additional single-cell RNA sequencing identified was due to impaired activation of the RAS/ERK signaling pathway. Consistent with these observations, calcium chelation or depletion of calcium in the culture media also impaired ERK activation in gemcitabine-resistant cells, and restored therapeutic responses to gemcitabine in vitro. We observed similar results using calcium channel blockers (CCBs) such as amlodipine, which inhibited prosurvival ERK signaling in vitro and markedly enhanced therapeutic responses to gemcitabine in both orthotopic xenografts and transgenic models of PDAC. Combined, these results offer insight into a potential means of gemcitabine resistance and suggest that select CCBs may provide a clinical benefit to PDAC patients receiving gemcitabine-based chemotherapy.
Assuntos
Antineoplásicos , Neoplasias Pancreáticas , Anlodipino/farmacologia , Anlodipino/uso terapêutico , Animais , Antineoplásicos/uso terapêutico , Bloqueadores dos Canais de Cálcio/farmacologia , Bloqueadores dos Canais de Cálcio/uso terapêutico , Calmodulina , Desoxicitidina/análogos & derivados , Humanos , Neoplasias Pancreáticas/patologia , Estados Unidos , Gencitabina , Neoplasias PancreáticasRESUMO
Trastuzumab is the first-line therapy for human epidermal growth factor receptor 2-positive (HER2+) breast cancer, but often patients develop acquired resistance. Although other agents are in clinical use to treat trastuzumab-resistant (TR) breast cancer; still, the patients develop recurrent metastatic disease. One of the primary mechanisms of acquired resistance is the shedding/loss of the HER2 extracellular domain, where trastuzumab binds. We envisioned any new agent acting downstream of the HER2 should overcome trastuzumab resistance. The mixed lineage kinase 3 (MLK3) activation by trastuzumab is necessary for promoting cell death in HER2+ breast cancer. We designed nanoparticles loaded with MLK3 agonist ceramide (PPP-CNP) and tested their efficacy in sensitizing TR cell lines, patient-derived organoids, and patient-derived xenograft (PDX). The PPP-CNP activated MLK3, its downstream JNK kinase activity, and down-regulated AKT pathway signaling in TR cell lines and PDX. The activation of MLK3 and down-regulation of AKT signaling by PPP-CNP induced cell death and inhibited cellular proliferation in TR cells and PDX. The apoptosis in TR cells was dependent on increased CD70 protein expression and caspase-9 and caspase-3 activities by PPP-CNP. The PPP-CNP treatment alike increased the expression of CD70, CD27, cleaved caspase-9, and caspase-3 with a concurrent tumor burden reduction of TR PDX. Moreover, the expressions of CD70 and ceramide levels were lower in TR than sensitive HER2+ human breast tumors. Our in vitro and preclinical animal models suggest that activating the MLK3-CD70 axis by the PPP-CNP could sensitize/overcome trastuzumab resistance in HER2+ breast cancer.
Assuntos
Antineoplásicos Imunológicos , Neoplasias da Mama , Ligante CD27 , Resistencia a Medicamentos Antineoplásicos , MAP Quinase Quinase Quinases , Nanopartículas , Trastuzumab , Animais , Antineoplásicos Imunológicos/farmacologia , Antineoplásicos Imunológicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Ligante CD27/metabolismo , Caspase 3/metabolismo , Caspase 9/metabolismo , Linhagem Celular Tumoral , Ceramidas/química , Feminino , Humanos , MAP Quinase Quinase Quinases/metabolismo , Camundongos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptor ErbB-2/análise , Trastuzumab/farmacologia , Trastuzumab/uso terapêutico , Ensaios Antitumorais Modelo de Xenoenxerto , MAP Quinase Quinase Quinase 11 Ativada por MitógenoRESUMO
Mixed lineage kinase 3 (MLK3), also known as MAP3K11, was initially identified in a megakaryocytic cell line and is an emerging therapeutic target in cancer, yet its role in immune cells is not known. Here, we report that loss or pharmacological inhibition of MLK3 promotes activation and cytotoxicity of T cells. MLK3 is abundantly expressed in T cells, and its loss alters serum chemokines, cytokines, and CD28 protein expression on T cells and its subsets. MLK3 loss or pharmacological inhibition induces activation of T cells in in vitro, ex vivo, and in vivo conditions, irrespective of T cell activating agents. Conversely, overexpression of MLK3 decreases T cell activation. Mechanistically, loss or inhibition of MLK3 down-regulates expression of a prolyl-isomerase, Ppia, which is directly phosphorylated by MLK3 to increase its isomerase activity. Moreover, MLK3 also phosphorylates nuclear factor of activated T cells 1 (NFATc1) and regulates its nuclear translocation via interaction with Ppia, and this regulates T cell effector function. In an immune-competent mouse model of breast cancer, MLK3 inhibitor increases Granzyme B-positive CD8+ T cells and decreases MLK3 and Ppia gene expression in tumor-infiltrating T cells. Likewise, the MLK3 inhibitor in pan T cells, isolated from breast cancer patients, also increases cytotoxic CD8+ T cells. These results collectively demonstrate that MLK3 plays an important role in T cell biology, and targeting MLK3 could serve as a potential therapeutic intervention via increasing T cell cytotoxicity in cancer.
Assuntos
Neoplasias da Mama/imunologia , Linfócitos do Interstício Tumoral/imunologia , MAP Quinase Quinase Quinases/metabolismo , Neoplasias Mamárias Experimentais/imunologia , Linfócitos T Citotóxicos/imunologia , Animais , Neoplasias da Mama/sangue , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Linhagem Celular Tumoral/transplante , Ciclofilina A/metabolismo , Feminino , Humanos , Ativação Linfocitária/efeitos dos fármacos , Linfócitos do Interstício Tumoral/efeitos dos fármacos , Linfócitos do Interstício Tumoral/metabolismo , MAP Quinase Quinase Quinases/antagonistas & inibidores , MAP Quinase Quinase Quinases/genética , Neoplasias Mamárias Experimentais/sangue , Neoplasias Mamárias Experimentais/patologia , Camundongos , Fatores de Transcrição NFATC/metabolismo , Fosforilação/efeitos dos fármacos , Fosforilação/imunologia , Cultura Primária de Células , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Piridinas/farmacologia , Piridinas/uso terapêutico , Pirróis/farmacologia , Pirróis/uso terapêutico , Linfócitos T Citotóxicos/efeitos dos fármacos , Linfócitos T Citotóxicos/metabolismo , Evasão Tumoral/efeitos dos fármacos , MAP Quinase Quinase Quinase 11 Ativada por MitógenoRESUMO
INTRODUCTION: The use of intracardiac echocardiography (ICE) is beneficial during the ablation of atrial fibrillation (AF). Evidence is conflicting regarding the clinical impact of using ICE on arrhythmia recurrence and mortality. METHODS: Patients undergoing catheter ablation of AF during 2010-2017 were identified using the International Classification of Diseases-9th and 10th Revision-Clinical Modification (ICD-9-CM and ICD-10-CM) from the Nationwide Readmissions Database. Propensity matching was used to generate a control group. Patient demographics, Charlson comorbidity indexes, time from discharge to readmission, and the reason of readmission were extracted. RESULTS: From 2010 to 2017, 51 129 patients were included in the analysis out of which ICE was used in 8005 (15.7%) patients. The in-hospital mortality at readmission was significantly higher in the patients without ICE use (2.9% vs. 1.7%, p = .02). The length of stay (LOS) at readmission was significantly higher in non-ICE arm (median [interquartile range, IQR]: 3 [2-6] vs. 2 [3-5] days, p < .0001) with similar healthcare-associated cost (HAC) in both the groups (median [IQR]: US$7507.3 [4057.8-15 474.2] vs. 7339.4 [4024.8-15 191.6], p = .43). Freedom from readmission was 12% higher (hazard ratio [HR] [95% confidence interval, CI]: 0.88 [0.83-0.94], p < .0001) with the use of ICE at 90-day follow-up, which was driven by 24% reduction in heart failure (HF) at follow-up (HR [95% CI]: 0.76 [0.60-0.96], p = .02). CONCLUSIONS: ICE use during AF ablation procedure reduces readmissions at 90 days by 12%, driven by a 24% decrease in HF-related admissions. The non-ICE arm showed a significantly higher LOS which offsets marginally higher HAC in the ICE arm.
Assuntos
Fibrilação Atrial , Ablação por Cateter , Insuficiência Cardíaca , Humanos , Fibrilação Atrial/diagnóstico por imagem , Fibrilação Atrial/cirurgia , Fibrilação Atrial/complicações , Readmissão do Paciente , Resultado do Tratamento , Ablação por Cateter/efeitos adversos , Insuficiência Cardíaca/complicações , Morbidade , EcocardiografiaRESUMO
Aberrant activation of Wnt/ß-catenin axis occurs in several gastrointestinal malignancies due to inactivating mutations of adenomatous polyposis coli (in colorectal cancer) or activating mutations of ß-catenin itself [in hepatocellular carcinoma (HCC)]. These lead to ß-catenin stabilization, increase in ß-catenin/T-cell factor (TCF)-mediated transcriptional activation, and target gene expression, many of which are involved in tumor progression. While studying pharmaceutical agents that can target ß-catenin in cancer cells, we observed that the plant compound berberine (BBR), a potent activator of AMP-activated protein kinase (AMPK), can reduce ß-catenin expression and downstream signaling in HCC cells in a dose-dependent manner. More in-depth analyses to understand the mechanism revealed that BBR-induced reduction of ß-catenin occurs independently of AMPK activation and does not involve transcriptional or post-translational mechanisms. Pretreatment with protein synthesis inhibitor cycloheximide antagonized BBR-induced ß-catenin reduction, suggesting that BBR affects ß-catenin translation. BBR treatment also antagonized mammalian target of rapamycin (mTOR) activity and was associated with increased recruitment of eukaryotic translation initiation factor 4E-binding protein (4E-BP) 1 in the translational complex, which was revealed by 7-methyl-cap-binding assays, suggesting inhibition of cap-dependent translation. Interestingly, knocking down 4E-BP1 and 4E-BP2 significantly attenuated BBR-induced reduction of ß-catenin levels and expression of its downstream target genes. Moreover, cells with 4E-BP knockdown were resistant to BBR-induced cell death and were resensitized to BBR after pharmacological inhibition of ß-catenin. Our findings indicate that BBR antagonizes ß-catenin pathway by inhibiting ß-catenin translation and mTOR activity and thereby reduces HCC cell survival. These also suggest that BBR could be used for targeting HCCs that express mutated/activated ß-catenin variants that are currently undruggable. SIGNIFICANCE STATEMENT: ß-catenin signaling is aberrantly activated in different gastrointestinal cancers, including hepatocellular carcinoma, which is currently undruggable. In this study we describe a novel mechanism of targeting ß-catenin translation via utilizing a plant compound, berberine. Our findings provide a new avenue of targeting ß-catenin axis in cancer, which can be utilized toward the designing of effective therapeutic strategies to combat ß-catenin-dependent cancers.
Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Berberina/farmacologia , Carcinoma Hepatocelular/metabolismo , Proteínas de Ciclo Celular/metabolismo , Fatores de Iniciação em Eucariotos/metabolismo , Neoplasias Hepáticas/metabolismo , beta Catenina/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/antagonistas & inibidores , Proteínas Adaptadoras de Transdução de Sinal/genética , Carcinoma Hepatocelular/genética , Proteínas de Ciclo Celular/antagonistas & inibidores , Proteínas de Ciclo Celular/genética , Fatores de Iniciação em Eucariotos/antagonistas & inibidores , Fatores de Iniciação em Eucariotos/genética , Células HEK293 , Células Hep G2 , Humanos , Neoplasias Hepáticas/genética , Biossíntese de Proteínas/efeitos dos fármacos , Biossíntese de Proteínas/fisiologia , beta Catenina/antagonistas & inibidores , beta Catenina/genéticaRESUMO
ß-hCG expression in breast cancer is highly controversial with reports supporting both protective and tumorigenic effects. It has also been reported that risk of breast cancer at an early age is increased with full-term pregnancies if a woman is a BRCA1 mutation carrier. We have already demonstrated that BRCA1-defective cells express high levels of ß-hCG and that when BRCA1 is restored, ß-hCG level is reduced. Also, BRCA1 can bind to the promoter and reduce the levels of ß-hCG. ß-hCG induces tumorigenicity in BRCA1-defective cells by directly binding to TGFBRII and induces TGFBRII-mediated cell proliferation. In this study, we analyzed the mechanism of action of ß-hCG on BRCA1 expression and its influence on drug sensitivity in breast cancer cells. We demonstrate that ß-hCG induces mutant BRCA1 protein expression in BRCA1 mutant cells; however, in BRCA1 wild-type cells, ß-hCG reduced wild-type BRCA1 protein expression. Transcriptionally, ß-hCG could induce Slug/LSD1-mediated repression of wild-type and mutant BRCA1 messenger RNA levels. However, ß-hCG induces HSP90-mediated stabilization of mutant BRCA1 and hence the overexpression of mutant BRCA1 protein, resulting in partial restoration of homologous recombination repair of damaged DNA. This contributes to drug resistance to HSP90 inhibitor 17AAG in BRCA1-defective cancer cells. A combination of HSP90 inhibitor and TGFBRII inhibitor has shown to sensitize ß-hCG expressing BRCA1-defective breast cancers to cell death. Targeting the ß-hCG-HSP90-TGFBRII axis could prove an effective treatment strategy for BRCA1-mutated breast tumors.
Assuntos
Proteína BRCA1/genética , Neoplasias da Mama/genética , Neoplasias da Mama/fisiopatologia , Gonadotropina Coriônica/metabolismo , Resistencia a Medicamentos Antineoplásicos , Animais , Proteína BRCA1/metabolismo , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Gonadotropina Coriônica/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Proteínas de Choque Térmico HSP90/metabolismo , Humanos , Camundongos , Camundongos Transgênicos , Mutação , Receptor do Fator de Crescimento Transformador beta Tipo II/metabolismo , Reparo de DNA por Recombinação , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
AIM: The purpose of this study was to evaluate and compare the cytotoxicity and genotoxicity of two bioceramic root canal sealers: EndoSequence BC and iRoot SP with zinc oxide eugenol sealers on fibroblast cell line. MATERIALS AND METHODS: The sealers tested were zinc oxide eugenol, EndoSequence BC, and iRoot SP. Each material was mixed according to the manufacturer's instructions and mounted into sterile polyethylene color-coded rings, for cytotoxicity and genotoxicity evaluation. After 48 hours, the set materials were transferred to previously marked wells and cytotoxicity evaluation to L929 murine fibroblast cells was done by 3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay. The percentages of viable cells were then calculated and values were statistically analyzed by Kruskal-Wallis test. The evaluation of genotoxicity of the materials to L929 murine fibroblast cells was carried out by Comet assay. To quantify deoxyribonucleic acid (DNA) damage, the following comet parameters were evaluated in the assay using Comet scoring software: tail length, tail moment, and Olive moment. The values were statistically analyzed using Kruskal-Wallis test with a significance value set to p < 0.05. RESULTS: The results of the study showed that both cytotoxicity and genotoxicity evaluation by MTT assay and Comet assay can be done on L929 murine fibroblast cell line. Among the three tested materials, zinc oxide eugenol showed maximum cytotoxicity to the cells (30.64% viable cells), followed by EndoSequence BC (71.33% viable cells) and iRoot SP (75.11% viable cells). The evaluation of DNA damage by genotoxicity assessment showed iRoot SP to be least genotoxic followed closely by EndoSequence BC. Zinc oxide eugenol was genotoxic and induced more DNA damage on the fibroblast cell line studied. The statistical analyses for both the assays were nonsignificant. CONCLUSION: All the three tested sealers showed varying degrees of cytotoxicity and genotoxicity while using fibro-blast cell line. Zinc oxide eugenol was most toxic in both the assays and iRoot SP showed least toxicity, followed closely by EndoSequence BC.
Assuntos
Fosfatos de Cálcio/toxicidade , Eugenol/toxicidade , Fibroblastos/efeitos dos fármacos , Óxidos/toxicidade , Selantes de Fossas e Fissuras/toxicidade , Materiais Restauradores do Canal Radicular/toxicidade , Silicatos/toxicidade , Óxido de Zinco/toxicidade , Animais , Linhagem Celular , Ensaio Cometa , Forramento da Cavidade Dentária , Combinação de Medicamentos , Técnicas In Vitro , Camundongos , Testes de MutagenicidadeRESUMO
INTRODUCTION: The closed reduction of a displaced nasal fracture is a preferred method in oral and maxillofacial surgery. This prospective study was conducted to evaluate the treatment outcome following closed reduction of nasal bone fractures. MATERIALS AND METHODS: A total of 20 patients with nasal bone fracture who underwent closed reduction were included in the study. The cases were operated under local or general anesthesia. The outcome of treatment was evaluated pre- and postoperatively through systematic follow-ups. Clinical assessment was done to evaluate functional (airway patency, nasal obstruction, crepitus) as well as esthetic parameters (facial symmetry, swelling, and nasal deviation). Functional and esthetic satisfaction of patients was assessed using visual analog scale (VAS) pre- and post-operatively. RESULTS: It was observed that there was significant improvement in both functional and esthetic parameters following closed reduction of nasal fractures. CONCLUSION: The present study suggested that closed reduction of nasal bone fracture is very effective in the management of nasal bone fractures. However, further studies with larger sample size in different clinical situations should be considered to confirm the efficacy of the same. CLINICAL SIGNIFICANCE: Closed reduction can be a viable and more conservative alternative in management of nasal fractures.
Assuntos
Redução Fechada/métodos , Fraturas Ósseas/cirurgia , Osso Nasal/lesões , Procedimentos Cirúrgicos Ortognáticos/métodos , Adulto , Estética/psicologia , Feminino , Fraturas Ósseas/psicologia , Humanos , Masculino , Pessoa de Meia-Idade , Satisfação do Paciente , Estudos Prospectivos , Resultado do Tratamento , Adulto JovemRESUMO
Novel chelated metal complexes were synthesized from carbohydrazones to thiocarbohydrazones using metal-based drug designing platforms and their combination effect with Pb, a naphthaquinone were analyzed for anticancer activity in breast cancer cell lines. A panel of BRCA1 wild-type and mutated breast cancer cells: MCF-7 (BRCA1+ /ER+ ), MDA-MB-231 (BRCA1+ /ERα- ), HCC-1937 (BRCA1- /ERα- ), HCC1937/wt BRCA1, MX1 (BRCA1- /ERα- ), and MDA-MB-436 (BRCA1- /ERα- ) were screened for anti-cancer activity. Cu2 (HL)(HSO4 ) · H2 O]SO4 · 6 H2 O (CS2) is the most potent anticancer agent among the copper carbohydrazone and thiocarbohydrazone complexes analyzed in this study. It can be suggested that the presence of sulphate, as pharmacologically active centre, can induce cytotoxicity more effectively when compared to chlorine, bromine, perchlorate, and methanol. This is the first report demonstrating that CS2 can bind to DNA by hindering BamH1 activity and could induce DNA double strand breaks as evidenced by γ-H2AX expression. In addition to this, CS2 could also act as a Topo II inhibitor at a much lower concentration than etoposide and induce apoptosis, making it a potent anticancer agent. In combination with Pb, a potent ROS inducer, CS2 could induce synergistic anti-cancer activity in HR/ BRCA1 defective breast cancer cells. This is the first study reporting the mechanism involved in the induction of apoptosis for a metal chelated copper carbohydrazone complex and its combination effects with Pb in HR defective, BRCA1 mutated breast cancer cells.
Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Proteína BRCA1/genética , Neoplasias da Mama/tratamento farmacológico , Hidrazonas/química , Animais , Antineoplásicos/metabolismo , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Cobre/química , Quebras de DNA de Cadeia Dupla/efeitos dos fármacos , DNA de Neoplasias/química , DNA de Neoplasias/metabolismo , Feminino , Humanos , Hidrazonas/farmacologia , Camundongos SCID , Mutação , Naftoquinonas/administração & dosagem , Naftoquinonas/farmacologia , Compostos Organometálicos/química , Compostos Organometálicos/farmacologia , Inibidores da Topoisomerase II/química , Inibidores da Topoisomerase II/farmacologia , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Human epidermal growth factor receptor 2 (HER2) is amplified in â¼ 15-20% of human breast cancer and is important for tumor etiology and therapeutic options of breast cancer. Up-regulation of HER2 oncogene initiates cascades of events cumulating to the stimulation of transforming PI3K/AKT signaling, which also plays a dominant role in supporting cell survival and efficacy of HER2-directed therapies. Although investigating the underlying mechanisms by which HER2 promotes cell survival, we noticed a profound reduction in the kinase activity of a pro-apoptotic mixed lineage kinase 3 (MLK3) in HER2-positive (HER2+) but not in HER2-negative (HER2-) breast cancer tissues, whereas both HER2+ and HER2- tumors expressed a comparable level of MLK3 protein. Furthermore, the kinase activity of MLK3 was inversely correlated with HER2+ tumor grades. Moreover, HER2-directed drugs such as trastuzumab and lapatinib as well as depletion of HER2 or HER3 stimulated MLK3 kinase activity in HER2+ breast cancer cell lines. In addition, the noted inhibitory effect of HER2 on MLK3 kinase activity was mediated via its phosphorylation on Ser(674) by AKT and that pharmacological inhibitors of PI3K/AKT prevented trastuzumab- and lapatinib-induced stimulation of MLK3 activity. Consistent with the pro-apoptotic function of MLK3, stable knockdown of MLK3 in the HER2+ cell line blunted the pro-apoptotic effects of trastuzumab and lapatinib. These findings suggest that HER2 activation inhibits the pro-apoptotic function of MLK3, which plays a mechanistic role in mediating anti-tumor activities of HER2-directed therapies. In brief, MLK3 represents a newly recognized integral component of HER2 biology in HER2+ breast tumors.
Assuntos
Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , MAP Quinase Quinase Quinases/metabolismo , Receptor ErbB-2/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular , Regulação para Baixo , Feminino , Humanos , MAP Quinase Quinase Quinases/antagonistas & inibidores , Sistema de Sinalização das MAP Quinases , Modelos Biológicos , Terapia de Alvo Molecular , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptor ErbB-3/antagonistas & inibidores , Receptor ErbB-3/metabolismo , MAP Quinase Quinase Quinase 11 Ativada por MitógenoRESUMO
Eventhough the role of BRCA1/2 in hereditary prostatic cancer is being unleashed at a rapid rate; their optimal clinical management remains undefined. Cancer stem cells are thought to be responsible for cancer chemoresistance and relapse, thus they represent a significant concern for cancer prognosis and therapy. In this study, we have analyzed the effect of Plumbagin (PB) and structurally related naphthaquinones on BRCA1/2 silenced prostate cancer cells and the ability of PB to target stem cells. Our cell proliferation studies showed that both PC-3 and DU145 cells were more sensitive to PB, though all the compounds induced mitochondrial potential loss, DNA fragmentation and morphological changes which are indicative of apoptosis. Both BRCA1/2 siRNA transfected PC-3 and DU145 cells exhibited increased sensitivity to PB. Gene expression profiling post PB treatment in BRCA1/2 silenced cells revealed that PB has a putative role in tumor suppression in BRCA defective cancers. Using flow cytometric analysis we have proved that PB has the putative ability to directly target CSCs. Overall studies suggest that PB's antitumour mechanisms holds promise for novel therapeutic approaches against BRCA mutated cancers as well as CSCs.
Assuntos
Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Proteína BRCA1/genética , Proteína BRCA2/genética , Naftoquinonas/farmacologia , Células-Tronco Neoplásicas/efeitos dos fármacos , Neoplasias da Próstata/tratamento farmacológico , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Masculino , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Próstata/efeitos dos fármacos , Próstata/patologia , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologiaRESUMO
The production of laccases from Trametes pubescens was investigated along with the role of nutrients and elicitors. Copper proved to be a fundamental inducer, although productivity yields were consistently enhanced only in the presence of additional compounds (textile dyes). Using a central composite design, the optimal culture condition was examined, by taking into consideration the three distinct variables and their combinatorial effect. The 290 U ml(-1) of laccases were produced after setting nitrogen, copper, and reactive blue 19 concentration; in a bioreactor, activity recovery was lower (90 U ml(-1)) and pellet morphology was different. The activity of the laccase crude extract was maximal at 60°C and stable for 14 h at 50°C and for 2 months at pH 6 and room temperature. The biotechnological potential was assessed, confirming the capacity to decolorize single or mixed solutions of textile dyes and to enhance the whitening yield of raw cotton fibers, working in synergism with the conventional H2O2-based method.
Assuntos
Cor , Corantes/química , Fibra de Algodão , Lacase/metabolismo , Trametes/enzimologia , Reatores Biológicos , Meios de Cultura , Fermentação , Concentração de Íons de Hidrogênio , Lacase/biossíntese , TemperaturaRESUMO
Calcia-Magnesia-Alumino Silicate (CMAS) is a form of molten siliceous residue generated at elevated temperatures within aeroengines. CMAS adheres to the surface of thermal barrier coatings (TBCs) and has the potential to cause significant damage to engine components, resulting in TBC failures. The aviation industry has long recognized CMAS as a substantial threat to aircraft engines, and this threat persists today. A substantial amount of research has been carried out, primarily focusing on gaining a fundamental understanding of the degradation mechanism of traditional TBCs manufactured using air plasma spraying (APS) and electron beam physical vapor deposition (EB-PVD) technologies after CMAS attack. A thorough understanding of why CMAS forms, its role in causing severe spallation, and how to prevent it is of significant concern both academically and industrially. This review article provides a detailed examination of the chemistry of CMAS and the resulting degradation mechanisms that the TBC may encounter throughout the aeroengine service life. This article also explores recent research, incorporating case studies, on the impact of CMAS attack on the resulting chemical and structural modifications of the ceramic topcoats. Current strategies designed to mitigate CMAS infiltration and perspectives for enhanced mitigation are discussed.
RESUMO
Missense mutations in the RAS family of oncogenes (HRAS, KRAS, and NRAS) are present in approximately 20% of human cancers, making RAS a valuable therapeutic target (Prior et al., Cancer Res 80:2969-2974, 2020). Although decades of research efforts to develop therapeutic inhibitors of RAS were unsuccessful, there has been success in recent years with the entrance of FDA-approved KRASG12C-specific inhibitors to the clinic (Skoulidis et al., N Engl J Med 384:2371-2381, 2021; Jänne et al., N Engl J Med 387:120-131, 2022). Additionally, KRASG12D-specific inhibitors are presently undergoing clinical trials (Wang et al., J Med Chem 65:3123-3133, 2022). The advent of these allele specific inhibitors has disproved the previous notion that RAS is undruggable. Despite these advancements in RAS-targeted therapeutics, several RAS mutants that frequently arise in cancers remain without tractable drugs. Thus, it is critical to further understand the function and biology of RAS in cells and to develop tools to identify novel therapeutic vulnerabilities for development of anti-RAS therapeutics. To do this, we have exploited the use of monobody (Mb) technology to develop specific protein-based inhibitors of selected RAS isoforms and mutants (Spencer-Smith et al., Nat Chem Biol 13:62-68, 2017; Khan et al., Cell Rep 38:110322, 2022; Wallon et al., Proc Natl Acad Sci USA 119:e2204481119, 2022; Khan et al., Small GTPases 13:114-127, 2021; Khan et al., Oncogene 38:2984-2993, 2019). Herein, we describe our combined use of Mbs and NanoLuc Binary Technology (NanoBiT) to analyze RAS protein-protein interactions and to screen for RAS-binding small molecules in live-cell, high-throughput assays.
Assuntos
Luciferases , Neoplasias , Proteínas Proto-Oncogênicas p21(ras) , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/genética , Oncogenes , Comunicação Celular , MutaçãoRESUMO
Triple-negative breast cancer (TNBC) is difficult to treat breast cancer subtype due to lack or insignificant expressions of targetable estrogen receptor (ER) and human epidermal growth factor receptor 2 (HER2). Therefore, finding a targetable protein or signaling pathway in TNBC would impact patient care. Here, we report that a member of the Mixed Lineage Kinase (MLK) family, MLK3, is an effector of G-protein-coupled proteinase-activated receptors 1 (PAR1) and targeting MLK3 by a small-molecule inhibitor prevented PAR1-mediated TNBC tumorigenesis. In silico and immunohistochemistry analysis of human breast tumors showed overexpression of PAR1 and MLK3 in TNBC tumors. Treating α-thrombin and PAR1 agonist increased MLK3 and JNK activities and induced cell migration in TNBC cells. The PAR1 positive/high (PAR1+/hi) population of TNBC cells showed aggressive tumor phenotype with increased MLK3 signaling. Moreover, combined inhibition of the PAR1 and MLK3 mitigated the TNBC tumor burden in preclinical TNBC models. Our data suggests that activation of the PAR1-MLK3 axis promotes TNBC tumorigenesis. Therefore, combinatorial therapy targeting MLK3 and PAR1 could effectively reduce TNBC tumor burden.
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Background Low back pain is known to be one of the leading causes of disability among the young and elderly population. Low back pain can stem from multiple sources, including spinal degeneration, injury, herniated discs, sciatica, and other contributing causes. This symptom significantly influences the quality of life of affected individuals. Its implications include extensive social and economic costs. Economic considerations arise from the fact that not all healthcare facilities accept the insurance plans available to retired individuals under Medicare. This places an additional burden on patients who must bear the financial responsibility for healthcare services not covered by their insurance plan. Florida, renowned as a favored state for retirement, consists of a demographic composition wherein 21% of its residents are aged 65 or older. A significant proportion of this demographic qualifies for Traditional Medicare (TM) and/or Medicare Advantage (MA) plans. Thus, understanding the disparities in healthcare access between Medicare and Medicare Advantage plans is crucial. This study aims to evaluate different Medicare insurances available in the market and their impact on the ease of accessibility to pain management specialists for the treatment of lower back pain in Florida patients. Methods We analyzed the Florida Department of Health database to identify the four counties in Florida with the highest Medicare enrollment rates in 2022: Miami-Dade, Palm Beach, Broward, and Pinellas County. Using the U.S. News and Report directory, 25 Pain Management-trained anesthesiologists were randomly selected from each of the four counties. Each office was contacted four times via telephone by four different team members to assess appointment availability for a fictional 65-year-old grandfather seeking treatment for chronic low back pain. The study examined appointment availability and accepted insurance types, including Cigna (commercial insurance), TM, Humana Gold Plus HMO (Medicare Advantage plan), and Blue Medicare Select PPO (Medicare Advantage plan). Practices without contact information or retired physicians were excluded from the analysis. Time to appointment was measured in business days. Results Of the 100 Pain Management Physicians contacted, 44 fit the inclusion criteria of being non-retired physicians, still practicing in one of the four counties with open offices and valid contact information. Blue Medicare Select PPO was accepted by 47.73%, Humana Gold Plus HMO by 56.82%, TM by 93.18%, and Cigna by 93.18% of the encounters. Blue Medicare select PPO and Humana Gold Plus HMO were accepted at significantly lower rates when compared to Traditional Medicare and Cigna with P values of P < .00001 and P < .000176, respectively. There was no significant difference found in the time to appointment between insurances with P value < 7. Conclusion The study found that patients enrolled in Medicare Advantage plans have significantly decreased access to care when compared to those enrolled in TM or commercial insurance. Further research is needed to elucidate the reasons behind differences in access to care across different insurances, as identified in the study.
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Advanced hepatocellular carcinoma (HCC) is a lethal disease, with limited therapeutic options. Mixed Lineage Kinase 3 (MLK3) is a key regulator of liver diseases, although its role in HCC remains unclear. Analysis of TCGA databases suggested elevated MAP3K11 (MLK3 gene) expression, and TMA studies showed higher MLK3 activation in human HCCs. To understand MLK3's role in HCC, we utlized carcinogen-induced HCC model and compared between wild-type and MLK3 knockout (MLK3-/-) mice. Our studies showed that MLK3 kinase activity is upregulated in HCC, and MLK3 deficiency alleviates HCC progression. MLK3 deficiency reduced proliferation in vivo and MLK3 inhibition reduced proliferation and colony formation in vitro. To obtain further insight into the mechanism and identify newer targets mediating MLK3-induced HCCs, RNA-sequencing analysis was performed. These showed that MLK3 deficiency modulates various gene signatures, including EMT, and reduces TGFB1&2 expressions. HCC cells overexpressing MLK3 promoted EMT via autocrine TGFß signaling. Moreover, MLK3 deficiency attenuated activated hepatic stellate cell (HSC) signature, which is increased in wild-type. Interestingly, MLK3 promotes HSC activation via paracrine TGFß signaling. These findings reveal TGFß playing a key role at different steps of HCC, downstream of MLK3, implying MLK3-TGFß axis to be an ideal drug target for advanced HCC management.
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Carcinoma Hepatocelular , Neoplasias Hepáticas , MAP Quinase Quinase Quinases , MAP Quinase Quinase Quinase 11 Ativada por Mitógeno , Transdução de Sinais , Fator de Crescimento Transformador beta , Animais , Humanos , Masculino , Camundongos , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/genética , Linhagem Celular Tumoral , Proliferação de Células , Transição Epitelial-Mesenquimal , Regulação Neoplásica da Expressão Gênica , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/genética , MAP Quinase Quinase Quinases/metabolismo , MAP Quinase Quinase Quinases/genética , Camundongos Knockout , Fator de Crescimento Transformador beta/metabolismoRESUMO
It has been shown earlier that plumbagin, a naturally occurring naphthaquinone has specific anticancer activity in BRCA1 blocked ovarian cancer cells. Plumbagin can induce estrogen dependent cell signaling and apoptosis in BRCA1 blocked ovarian cancer cells. Being a reactive oxygen species (ROS) generator and apoptosis inducing agent, plumbagin has immense potential as a promising anticancer agent. In this study we analyzed whether there would be increased anticancer activity if the positions of the functional groups on plumbagin were altered and further to analyze the detailed molecular mechanism of action of the lead molecule. Methods like MTT assay, apoptosis analysis by flow cytometry, assessment of mitochondrial membrane potential-Δψm , suppression subtractive hybridization, microarray, molecular docking and estrogen receptor-DNA binding activity by electrophoresis mobility shift assay (EMSA) were adopted for assessing the anticancer activity. Consequently we found that, plumbagin was the most potent anticancer agent when compared to structurally related compounds. The anti-cancer activities were in the order plumbagin > 1,4-naphthaquinone > juglone > lawsone > menadione. Molecular docking studies showed that plumbagin could be well docked in the receptor ligand complex of TRAIL-DR5 complexes to activate the extrinsic pathway of apoptosis. Since the antiproliferative activity of plumbagin could be reduced by inhibiting ERα, we speculated that plumbagin interferes with the binding of ERα to ERE and we confirmed this by EMSA. This study clearly indicates that plumbagin can induce multiple pathways of apoptosis and cell cycle arrest in BRCA1 blocked cells compared to unblocked cells.
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Antineoplásicos Fitogênicos/farmacologia , Proteína BRCA1/genética , Neoplasias da Mama/tratamento farmacológico , Naftoquinonas/química , Naftoquinonas/farmacologia , Neoplasias Ovarianas/tratamento farmacológico , Relação Estrutura-Atividade , Antineoplásicos Fitogênicos/química , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais/métodos , Receptor alfa de Estrogênio/metabolismo , Feminino , Técnicas de Inativação de Genes , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Simulação de Acoplamento Molecular , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/patologia , Poli(ADP-Ribose) Polimerases/metabolismo , Elementos de Resposta/efeitos dos fármacos , TranscriptomaRESUMO
AIM: To evaluate the relative ability of 4 mg dose of intraoperative dexamethasone, administered submucosally, to reduce the postoperative discomfort after third molar surgery. MATERIALS AND METHODS: A total of 100 patients requiring surgical removal of a single mandibular third molar were included. The experimental group (50) received dexamethasone 4 mg as submucosal injection and control group (50) received no drugs. The maximum interincisal distance and facial contours were measured at baseline and at postsurgery days 2 and 7. The measurement of pain was done using visual analog scale (VAS). RESULTS: None of the patients developed wound infection or any serious postoperative complications. Postoperative edema tended to be less severe on the second postoperative day in the experimental group and the result was statistically significant. There were no significant differences in the reduction of pain and trismus between the two groups studied. CONCLUSION: Submucosal administration of dexamethasone sodium phosphate (4 mg) results in reduction of postoperative edema, comparable with or greater than other routes of administration. Presumably, a higher effective drug concentration at the site of injury without loss due to distribution to other compartments may be achieved, and the submucosal route is convenient for both the surgeon and the patient. CLINICAL SIGNIFICANCE: Submucosal route of administration of dexamethasone (4 mg) is effective in reducing postoperative discomfort after third molar surgeries.
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Anti-Inflamatórios/administração & dosagem , Dexametasona/administração & dosagem , Glucocorticoides/administração & dosagem , Dente Serotino/cirurgia , Dor Pós-Operatória/prevenção & controle , Extração Dentária/métodos , Administração Bucal , Administração através da Mucosa , Edema/prevenção & controle , Seguimentos , Humanos , Injeções , Mandíbula/cirurgia , Medição da Dor/métodos , Complicações Pós-Operatórias/prevenção & controle , Pré-Medicação , Estudos Prospectivos , Amplitude de Movimento Articular/fisiologia , Trismo/prevenção & controle , Escala Visual AnalógicaRESUMO
Background: Use of semi-active and active robotic system for performing Total Knee Arthroplasty (TKA) is increasing. The novel fully automated active robotic system performs milling of the bone surfaces with a high speed burr. The aim of the current study was to assess the safety and efficacy of the system in robotic assisted TKA (RA-TKA). Materials and methods: A single center clinical trial was conducted following 30 knees undergoing active RA-TKA for 6 months. Inclusion criteria were patients undergoing RA-TKA for end stage arthritis. Patients undergoing conventional TKA and revision TKA were excluded from the study. Sample size was estimated to be 28 patients with α error of 0.05 and ß error of 0.2 with power of study being 80. A pre-defined list of RA-TKA adverse events was employed to study the safety of the system. Efficacy was judged by comparing the planned versus achieved Implant size, alignment and limb alignment on post-operative radiographs. The post-operative clinical evaluation was done by an independent observer who was not part of the operating team. The primary safety and efficacy hypothesis was tested using a one sided Exact binomial test. The p value < 0.05 was considered significant. Results: Pre-defined adverse events did not occur in any of the 30 RA-TKA (statistically significant p value < 0.001). The implant size accuracy was 100% (30 out of 30 knees) for femoral component and 96.67% (29 out of 30 knees) for tibial component (statistically significant, Chi-squared test, p value 0.0105 and 0.0461 respectively). The implant position and limb alignment was accurate in 100% of patients (p value < 0.001). Conclusion: Early experience of the use of fully automated active robotic system in TKA shows that it is safe and also is effective in achieving accurate implant size and implant/limb alignment.