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1.
Natl J Maxillofac Surg ; 14(1): 79-85, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37273426

RESUMO

Background: General anesthesia remains the most popular technique for ambulatory surgeries with patients, surgeons, and anesthesia providers. The supraglottic airway (SGA) devices result in fewer incidences of sore throat, laryngospasm, coughing, and hoarseness as compared to inserting a tracheal tube. This study was conducted to compare two second-generation SGA devices, LMA ProSeal and I-gel airway, in anesthetized patients on spontaneous ventilation during daycare procedures to establish the superior SGA device. Methodology: This prospective randomized study was done on 90 patients of either sex aged 15-60 years, ASA grade I-II, Mallampatti grade I and II, and BMI between 20 and 30 kg/m2 scheduled for elective surgeries of duration less than 90 min. Patients were randomly allocated into two groups-group A (I-gel) and group B (LMA ProSeal). Insertion parameters, hemodynamic responses, oxygenation, ventilation, peak airway pressure (PAP), and postoperative complications were recorded. Statistical analysis was done using SPSS version 21.0 statistical analysis software. Results: Mean insertion time of LMA ProSeal was found to be significantly higher as compared to I-gel (33.27 ± 3.88 vs 18.49 ± 3.18 s; P < 0.001). No significant difference was found between the groups in the number of attempts and of operators attempted for insertion, as well as in hemodynamic response, oxygenation, and ventilation. Postoperative complications were lesser in group A. Conclusion: I-gel is an easy-to-insert cuffless SGA device requiring lesser time for insertion, provides adequate ventilation with lesser postoperative complications and thus appears to be better than LMA ProSeal.

2.
J Clin Invest ; 132(13)2022 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-35653190

RESUMO

Mitochondrial proteostasis, regulated by the mitochondrial unfolded protein response (UPRmt), is crucial for maintenance of cellular functions and survival. Elevated oxidative and proteotoxic stress in mitochondria must be attenuated by the activation of a ubiquitous UPRmt to promote prostate cancer (PCa) growth. Here we show that the 2 key components of the UPRmt, heat shock protein 60 (HSP60, a mitochondrial chaperonin) and caseinolytic protease P (ClpP, a mitochondrial protease), were required for the development of advanced PCa. HSP60 regulated ClpP expression via c-Myc and physically interacted with ClpP to restore mitochondrial functions that promote cancer cell survival. HSP60 maintained the ATP-producing functions of mitochondria, which activated the ß-catenin pathway and led to the upregulation of c-Myc. We identified a UPRmt inhibitor that blocked HSP60's interaction with ClpP and abrogated survival signaling without altering HSP60's chaperonin function. Disruption of HSP60-ClpP interaction with the UPRmt inhibitor triggered metabolic stress and impeded PCa-promoting signaling. Treatment with the UPRmt inhibitor or genetic ablation of Hsp60 inhibited PCa growth and progression. Together, our findings demonstrate that the HSP60-ClpP-mediated UPRmt is essential for prostate tumorigenesis and the HSP60-ClpP interaction represents a therapeutic vulnerability in PCa.


Assuntos
Chaperonina 60 , Neoplasias da Próstata , Animais , Chaperonina 60/genética , Chaperonina 60/metabolismo , Humanos , Masculino , Camundongos , Mitocôndrias/genética , Mitocôndrias/metabolismo , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo , Peptídeo Hidrolases/metabolismo , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Resposta a Proteínas não Dobradas
3.
J Family Med Prim Care ; 10(1): 237-242, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34017733

RESUMO

BACKGROUND AND AIMS: Pre-anesthesia checkup (PAC) gives unique opportunity for providing necessary information, patient education and allaying anxiety. Our objective was to measure the effect of preoperative multimedia video information (self made short video of 12 minutes) on patient's anxiety and hemodynamic parameters during surgery under spinal anesthesia. METHODS: This prospective randomized study was conducted in 80 patients of either sex with ASA physical status I and II posted for lower limb surgery under spinal anesthesia. Patents were randomized to control or test group. At the end of preoperative visit, patients in test group watched the film and patient in control group did not watch any video. Verbal briefing by the attending anesthesiologist on the day of surgery was given to all patients of both the groups. Anxiety using Amsterdam Preoperative Anxiety and Information Scale (APAIS) and hemodynamic parameters (SBP, DBP and HR) at various time intervals (A1: Baseline, A2: post intervention, A3: just before surgery, A4: after surgery) were measured. RESULTS: Baseline anxiety (A1) scores were severe in both the groups and showed no statistical significance (P = 0.436). Patients in test group (video) showed better/lower anxiety levels than the control group (non video) at A2 (P = 0.020) and A3 (P = 0.005) respectively, similarly hemodynamic parameters were better controlled and showed lesser deviation from baseline values in test group as compared to control group and showed statistical significant difference (P < 0.001) just before surgery. CONCLUSION: Combination of multimedia based video information at the time of PAC and short verbal briefing on the day of surgery by the attending anesthesiologist provides effective management of perioperative anxiety. It can be cost effective way of enhancing patient care and providing adequate information to people with reading and comprehension difficulties.

4.
Cureus ; 13(12): e20237, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35004052

RESUMO

Background The epidural analgesia technique is effective for labor analgesia and combinations of various local anesthetics with lipophilic opioids like fentanyl are used. However, fentanyl can cause an increased incidence of pruritus, urinary retention, nausea, vomiting, giddiness, shivering, and respiratory depression. Dexmedetomidine and clonidine are selective alpha 2 agonists with analgesic properties and have been used via the neuraxial route with local anesthetics for the same without the side effects of fentanyl. Thus, the primary objective was to assess and compare the analgesic efficacy of the two-drug combinations by the visual analog scale (VAS) score. Methods Fifty-four primigravida women were randomly allocated in two groups of 27 each and were given an initial bolus of 10 mL of 0.125% levobupivacaine with dexmedetomidine 0.5 ug/kg in Group A and with clonidine 1 µg/kg in Group B. Subsequently, each patient received a background infusion rate of 10 mL/h, a bolus dose of 5 ml, and a lock-out interval of 10 min via a patient-controlled-analgesia (PCA) pump. The blood pressure, heart rate, and severity of pain using VAS were assessed. Durations of the stages of labor, rate of instrumental delivery, and cesarean section, side effects, maternal sedation, and neonatal Apgar scores were also recorded. Results VAS scores in both the groups progressively decreased to <3 by 15 min with significant differences at five, 10, 15, and 120 min being lower in group A. Onset of analgesia and time for maximum analgesia was significantly shorter in group A. There was a significant decrease in hemodynamic parameters from baseline in both groups. The fall in heart rate was significantly greater in Group A and at almost all the time intervals after baseline, diastolic blood pressure (DBP) was also lower in group A. Maternal motor blockade scores, the intensity of maternal sedation, the incidence of maternal complications, the duration of the first and second stage of labor, the rate of instrumental delivery and cesarean section, total analgesic dose and PCA bolus requirement, and neonatal Apgar scores did not show a significant difference between the two groups. Conclusion Both dexmedetomidine and clonidine provide hemodynamically stable labor with a fall in heart rate and maternal blood pressure in the initial hours. Dexmedetomidine has the advantage of faster onset of analgesia and time for maximum analgesia.

5.
Biomark Med ; 14(12): 1109-1119, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32969251

RESUMO

Aim: To investigate the possible association between MMP-2 (-1575 G/A, -1306 C/T) and its inhibitor TIMP-2 (-418 G/C) functional polymorphisms with development of severity in systemic lupus erythematosus (SLE) patients. Materials & methods: 150 SLE patients and matched healthy controls were recruited. Polymorphisms were detected by PCR-RFLP and serum levels by ELISA. Results: Mean MMP-2 and TIMP-2 serum level and mRNA expression were significantly increased in SLE cases as compared with controls (p < 0.0001). The concomitant presence of both MMP-2 1575A and its inhibitor TIMP-2 418C alleles synergistically increased the risk of SLE by 3.25-fold (CI: 1.44-7.34, p = 0.003). Conclusion: MMP-2, TIMP-2 and MMP-2/TIMP-2 ratios may act as biomarkers for susceptibility to SLE.


Assuntos
Predisposição Genética para Doença , Lúpus Eritematoso Sistêmico/genética , Metaloproteinase 2 da Matriz/genética , Inibidor Tecidual de Metaloproteinase-2/genética , Adolescente , Adulto , Feminino , Expressão Gênica , Marcadores Genéticos , Humanos , Masculino , Metaloproteinase 2 da Matriz/sangue , Polimorfismo Genético , Índice de Gravidade de Doença , Inibidor Tecidual de Metaloproteinase-2/sangue , Adulto Jovem
6.
Cancer Res ; 79(7): 1353-1368, 2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30765600

RESUMO

Although African-American (AA) patients with prostate cancer tend to develop greater therapeutic resistance and faster prostate cancer recurrence compared with Caucasian-American (CA) men, the molecular mechanisms of this racial prostate cancer disparity remain undefined. In this study, we provide the first comprehensive evidence that cytochrome c deficiency in AA primary tumors and cancer cells abrogates apoptosome-mediated caspase activation and contributes to mitochondrial dysfunction, thereby promoting therapeutic resistance and prostate cancer aggressiveness in AA men. In AA prostate cancer cells, decreased nuclear accumulation of nuclear respiration factor 1 (Nrf1) and its subsequent loss of binding to the cytochrome c promoter mediated cytochrome c deficiency. The activation of cellular Myc (c-Myc) and NF-κB or inhibition of AKT prevented nuclear translocation of Nrf1. Genetic and pharmacologic inhibition of c-Myc and NF-κB or activation of AKT promoted Nrf1 binding to cytochrome c promoter, cytochrome c expression, caspase activation, and cell death. The lack of p-Drp1S616 in AA prostate cancer cells contributed to defective cytochrome c release and increased resistance to apoptosis, indicating that restoration of cytochrome c alone may be insufficient to induce effective apoptosis. Cytochrome c deficiency promoted the acquisition of glycolytic phenotypes and mitochondrial dysfunction, whereas cytochrome c restoration via inhibition of c-Myc and NF-κB or activation of AKT attenuated glycolysis in AA prostate cancer cells. Inhibition of c-Myc and NF-κB enhanced the efficacy of docetaxel in tumor xenografts. Therefore, restoring cytochrome c may overcome therapeutic resistance and prostate cancer aggressiveness in AA men. Overall, this study provides the first comprehensive experimental, mechanistic, and clinical evidence for apoptosome and mitochondrial dysfunction in prostate cancer racial disparity. SIGNIFICANCE: Mechanistic insights on prostate cancer health disparity among American men provide novel approaches to restore mitochondrial function, which can address therapeutic resistance and aggressiveness in African-American men with prostate cancer.


Assuntos
Apoptossomas/fisiologia , Negro ou Afro-Americano , Citocromos c/deficiência , Mitocôndrias/fisiologia , Neoplasias da Próstata/patologia , Animais , Linhagem Celular Tumoral , Citocromos c/metabolismo , Humanos , Masculino , Camundongos , Camundongos SCID , Membranas Mitocondriais/enzimologia , NF-kappa B/metabolismo , Fator 1 Nuclear Respiratório/metabolismo , Fosforilação Oxidativa , Proteínas Proto-Oncogênicas c-myc/metabolismo
7.
Cancer Lett ; 413: 82-93, 2018 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-29107110

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) is highly aggressive disease and current treatment regimens fail to effectively cure PDAC. Development of resistance to current therapy is one of the key reasons for this outcome. Nimbolide (NL), a triterpenoid obtained from Azadirachta indica, exhibits anticancer properties in various cancer including PDAC cells. However, the underlying mechanism of this anticancer agent in PDAC cells remains undefined. We show that NL exerts a higher level of apoptotic cell death compared to the first-line agent gemcitabine for PDAC, as well as other anticancer agents including sorafenib and curcumin. The anticancer efficacy of NL was further evidenced by a reduction in the CD44+ as well as cancer stem-like cell (CSC) population, as it causes decreased sphere formation. Mechanistically, the anticancer efficacy of NL associates with reduced mutant p53 as well as increased mitochondrial activity in the form of increased mitochondrial reactive oxygen species and mitochondrial mass. Together, this study highlights the therapeutic potential of NL in mutant p53 expressing pancreatic cancer.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Carcinoma Ductal Pancreático/tratamento farmacológico , Inibidores de Caspase/farmacologia , Receptores de Hialuronatos/metabolismo , Limoninas/farmacologia , Mitocôndrias/efeitos dos fármacos , Células-Tronco Neoplásicas/efeitos dos fármacos , Neoplasias Pancreáticas/tratamento farmacológico , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/metabolismo , Carcinoma Ductal Pancreático/patologia , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Desoxicitidina/análogos & derivados , Desoxicitidina/farmacologia , Relação Dose-Resposta a Droga , Humanos , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Mutação , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Espécies Reativas de Oxigênio/metabolismo , Fatores de Tempo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Gencitabina
8.
Sci Rep ; 7(1): 10451, 2017 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-28874842

RESUMO

Prostate cancer (PCa) is one of the leading cancers in men in the USA. Lack of experimental tools that predict therapy response is one of the limitations of current therapeutic regimens. Mitochondrial dysfunctions including defective oxidative phosphorylation (OXPHOS) in cancer inhibit apoptosis by modulating ROS production and cellular signaling. Thus, correction of mitochondrial dysfunction and induction of apoptosis are promising strategies in cancer treatment. We have used Fluorescence Lifetime Imaging Microscopy (FLIM) to quantify mitochondrial metabolic response in PCa cells by tracking auto-fluorescent NAD(P)H, FAD and tryptophan (Trp) lifetimes and their enzyme-bound fractions as markers, before and after treatment with anti-cancer drug doxorubicin. A 3-channel FLIM assay and quantitative analysis of these markers for cellular metabolism show in response to doxorubicin, NAD(P)H mean fluorescence lifetime (τm) and enzyme-bound (a2%) fraction increased, FAD enzyme-bound (a1%) fraction was decreased, NAD(P)H-a2%/FAD-a1% FLIM-based redox ratio and ROS increased, followed by induction of apoptosis. For the first time, a FRET assay in PCa cells shows Trp-quenching due to Trp-NAD(P)H interactions, correlating energy transfer efficiencies (E%) vs NAD(P)H-a2%/FAD-a1% as sensitive parameters in predicting drug response. Applying this FLIM assay as early predictor of drug response would meet one of the important goals in cancer treatment.


Assuntos
Antibióticos Antineoplásicos/farmacologia , Doxorrubicina/farmacologia , Metabolismo Energético/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Neoplasias da Próstata/metabolismo , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Flavina-Adenina Dinucleotídeo/metabolismo , Humanos , Masculino , Microscopia de Fluorescência , NADP/metabolismo , Imagem Óptica , Oxirredução , Fosforilação Oxidativa/efeitos dos fármacos , Estresse Oxidativo , Espécies Reativas de Oxigênio , Triptofano/metabolismo
9.
Biochim Biophys Acta Rev Cancer ; 1867(1): 58-66, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27988298

RESUMO

Abrogation of endoplasmic reticulum (ER) protein folding triggered by exogenous or endogenous factors, stimulates a cellular stress response, termed ER stress. ER stress re-establishes ER homeostasis through integrated signaling termed the ER-unfolded protein response (UPRER). In the presence of severe toxic or prolonged ER stress, the pro-survival function of UPRER is transformed into a lethal signal transmitted to and executed through mitochondria. Mitochondria are key for both apoptotic and autophagic cell death. Thus ER is vital in sensing and coordinating stress pathways to maintain overall physiological homeostasis. However, this function is deregulated in cancer, resulting in resistance to apoptosis induction in response to various stressors including therapeutic agents. Here we review the connections between ER stress and mitochondrial apoptosis, describing potential cancer therapeutic targets.


Assuntos
Apoptose/fisiologia , Estresse do Retículo Endoplasmático/fisiologia , Retículo Endoplasmático/patologia , Mitocôndrias/patologia , Neoplasias/patologia , Resposta a Proteínas não Dobradas/fisiologia , Animais , Humanos , Dobramento de Proteína , Transdução de Sinais/fisiologia
10.
Front Biosci (Schol Ed) ; 9(1): 154-164, 2017 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-27814581

RESUMO

The gap between prostate cancer disparities among American men is narrowing, which is mostly due to increased screening of African American (AA) men. However, the biological reasons for prostate cancer disparities among American men still remain undefined. Mitochondrion, an organelle within cells, regulates both cell survival and cell death mechanisms. These cellular signaling pathways require various proteins localized to mitochondria, which are encoded by both nuclear DNA (nDNA) and mitochondrial DNA (mtDNA). Interestingly, prostate tissues from AA men harbor reduced mtDNA content compared to Caucasian American (CA) men. Therefore, changes in mitochondrial genes may have detrimental consequences in terms of cellular signaling regulated by mitochondria in AA men. This review describes the plausible underlying mechanism of mtDNA depletion and its impact in driving resistance to therapy leading to faster progression and poor prognosis in African American men with prostate cancer. Since defective cellular signaling is critical for prostate cancer cell survival, restoring mitochondrial function may provide strategies to alleviate prostate cancer disparities among American men.


Assuntos
Negro ou Afro-Americano , Disparidades nos Níveis de Saúde , Mitocôndrias/genética , Mitocôndrias/metabolismo , Neoplasias da Próstata/etnologia , Neoplasias da Próstata/fisiopatologia , População Branca , DNA Mitocondrial/genética , DNA Mitocondrial/metabolismo , Humanos , Masculino , Fosforilação Oxidativa , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Estados Unidos
11.
Asian Pac J Cancer Prev ; 17(7): 3043-51, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27509927

RESUMO

Controlled remodeling of the extracellular matrix (ECM) is essential for cell growth, invasion and metastasis. Matrix metalloproteinases (MMPs) are a family of secreted, zincdependent endopeptidases capable of degradation of ECM components. The expression and activity of MMPs in a variety of human cancers have been intensively studied. They play important roles at different steps of malignant tumor formation and have central significance in embryogenesis, tissue remodeling, inflammation, angiogenesis and metastasis. However, increasing evidence demonstrates that MMPs are involved earlier in tumorigenesis. Recent studies also suggest that MMPs play complex roles in tumor progression. MMPs and membrane type (MT)MMPs are potentially significant therapeutic targets in many cancers, so that designing of specific MMP inhibitors would be helpful for clinical trials. Here, we review the pleiotropic roles of the MMP system in hematological malignancies invitro and invivo models.


Assuntos
Neoplasias Hematológicas/metabolismo , Metaloproteinases da Matriz/metabolismo , Animais , Carcinogênese/efeitos dos fármacos , Carcinogênese/metabolismo , Progressão da Doença , Matriz Extracelular/efeitos dos fármacos , Matriz Extracelular/metabolismo , Neoplasias Hematológicas/tratamento farmacológico , Humanos , Inibidores de Metaloproteinases de Matriz/farmacologia , Inibidores de Metaloproteinases de Matriz/uso terapêutico
13.
Asian Pac J Cancer Prev ; 17(3): 1519-29, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27039800

RESUMO

BACKGROUND: Matrix metalloproteinase -2 (gelatinase-A, Mr 72,000 type IV collagenase, MMP-2) and -9 (gelatinase-B, Mr 92,000 type IV collagenase, MMP-9) are key molecules that play roles in tumor growth, invasion, tissue remodeling, metastasis and stem-cell regulation by digesting extracellular matrix barriers. MMP-2 and -9 are well known to impact on solid cancer susceptibility, whereas, in hematological malignancies, a paucity of data is available to resolve the function of these regulatory molecules in bone marrow mononuclear cells (BM-MNCs) and stromal cells of myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML). OBJECTIVES: The present study aimed to investigate mRNA expression and gelatinase A and B secretion from BM-MNCs in vitro and genotypic associations of MMP-2 (-1306 C/T; rs243865), MMP-9 (-1562 C/T; rs3918242), tissue inhibitor of metalloproteinase -1 (TIMP-1) (372T/C; rs4898, Exon 5) and TIMP-2 (-418G/C; rs8179090) in MDS and AML. RESULTS: The study covered cases of confirmed MDS (n=50), AML (n=32) and healthy controls (n=110). MMP- 9 mRNA expression revealed 2 fold increased expression in MDS-RAEB II and 2.5 fold in AML M-4 (60-70% blasts). Secretion of gelatinase- B also revealed the MMP-9 mRNA expression and ELISA data also supported these data. We noted that those patients having more blast crises presented with more secretion of MMP-9 and its mRNA expression. In contrast MMP-9 (-1562 C/T) showed significant polymorphic associations in MDS (p<0.02) and AML (p<0.02). MMP-9 mRNA expression of C/T and T/T genotypes were 1.5 and 2.5 fold increased in MDS and AML respectively. In AML, MMP-2 C/T and T/T genotypes showed 2.0 fold mRNA expression. Only MMP-9 (-1306 C/T) showed significant 4 fold (p<0.001) increased risk with chemical and x-ray exposed MDS, while tobacco and cigarette smokers have 3 fold (p<0.04) risk in AML. CONCLUSIONS: In view of our results, MMP-9 revealed synergistic secretion and expression in blast crises of MDS and AML with 'gene' polymorphic effects and is significantly associated with increased risk with tobacco, cigarette and environmental exposure. Release and secretion of these enzymes may influence hematopoietic cell behavior and may be important in the clinical point of view. It may offer valuable tools for diagnosis and prognosis, as well as possible targets for the treatments.


Assuntos
Biomarcadores Tumorais/metabolismo , Crise Blástica/metabolismo , Células da Medula Óssea/metabolismo , Leucemia Mieloide Aguda/metabolismo , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Síndromes Mielodisplásicas/metabolismo , Biomarcadores Tumorais/genética , Crise Blástica/patologia , Células da Medula Óssea/patologia , Estudos de Casos e Controles , Ensaio de Imunoadsorção Enzimática , Seguimentos , Humanos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patologia , Metaloproteinase 2 da Matriz/genética , Metaloproteinase 9 da Matriz/genética , Síndromes Mielodisplásicas/genética , Síndromes Mielodisplásicas/patologia , Gradação de Tumores , Estadiamento de Neoplasias , Prognóstico , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Índice de Gravidade de Doença
14.
Br J Cancer ; 114(10): 1090-100, 2016 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-27115471

RESUMO

BACKGROUND: African-American (AA) patients with prostate cancer (PCa) respond poorly to current therapy compared with Caucasian American (CA) PCa patients. Although underlying mechanisms are not defined, mitochondrial dysfunction is a key reason for this disparity. METHODS: Cell death, cell cycle, and mitochondrial function/stress were analysed by flow cytometry or by Seahorse XF24 analyzer. Expression of cellular proteins was determined using immunoblotting and real-time PCR analyses. Cell survival/motility was evaluated by clonogenic, cell migration, and gelatin zymography assays. RESULTS: Glycolytic pathway inhibitor dichloroacetate (DCA) inhibited cell proliferation in both AA PCa cells (AA cells) and CA PCa cells (CA cells). AA cells possess reduced endogenous reactive oxygen species, mitochondrial membrane potential (mtMP), and mitochondrial mass compared with CA cells. DCA upregulated mtMP in both cell types, whereas mitochondrial mass was significantly increased in CA cells. DCA enhanced taxol-induced cell death in CA cells while sensitising AA cells to doxorubicin. Reduced expression of heat shock proteins (HSPs) was observed in AA cells, whereas DCA induced expression of CHOP, C/EBP, HSP60, and HSP90 in CA cells. AA cells are more aggressive and metastatic than CA cells. CONCLUSIONS: Restoration of mitochondrial function may provide new option for reducing PCa health disparity among American men.


Assuntos
Ácido Dicloroacético/farmacologia , Proteínas de Choque Térmico/metabolismo , Mitocôndrias/efeitos dos fármacos , Neoplasias da Próstata/etnologia , Neoplasias da Próstata/metabolismo , Negro ou Afro-Americano , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Masculino , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Estados Unidos
15.
Mol Oncol ; 10(7): 949-65, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27106131

RESUMO

Development of therapeutic resistance is responsible for most prostate cancer (PCa) related mortality. Resistance has been attributed to an acquired or selected cancer stem cell phenotype. Here we report the histone deacetylase inhibitor apicidin (APC) or ER stressor thapsigargin (TG) potentiate paclitaxel (TXL)-induced apoptosis in PCa cells and limit accumulation of cancer stem cells. TXL-induced responses were modulated in the presence of TG with increased accumulation of cells at G1-phase, rearrangement of the cytoskeleton, and changes in cytokine release. Cytoskeletal rearrangement was associated with modulation of the cytoplasmic and mitochondrial unfolded protein response leading to mitochondrial dysfunction and release of proapoptotic proteins from mitochondria. TXL in combination with APC or TG enhanced caspase activation. Importantly, TXL in combination with TG induced caspase activation and apoptosis in X-ray resistant LNCaP cells. Increased release of transforming growth factor-beta (TGF-ß) was observed while phosphorylated ß-catenin level was suppressed with TXL combination treatments. This was accompanied by a decrease in the CD44(+)CD133(+) cancer stem cell-like population, suggesting treatment affects cancer stem cell properties. Taken together, combination treatment with TXL and either APC or TG induces efficient apoptosis in both proliferating and cancer stem cells, suggesting this therapeutic combination may overcome drug resistance and recurrence in PCa.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Apoptose , Citoesqueleto/metabolismo , Mitocôndrias/metabolismo , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/metabolismo , Resposta a Proteínas não Dobradas , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Apoptose/efeitos dos fármacos , Apoptose/efeitos da radiação , Caspases/metabolismo , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos da radiação , Morte Celular/efeitos dos fármacos , Morte Celular/efeitos da radiação , Linhagem Celular Tumoral , Citoesqueleto/efeitos dos fármacos , Citoesqueleto/efeitos da radiação , Ativação Enzimática/efeitos dos fármacos , Fase G1/efeitos dos fármacos , Fase G1/efeitos da radiação , Fase G2/efeitos dos fármacos , Fase G2/efeitos da radiação , Proteínas de Choque Térmico HSP70/metabolismo , Humanos , Interferon gama/metabolismo , Interleucina-8/metabolismo , Masculino , Metaloproteinases da Matriz/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Potencial da Membrana Mitocondrial/efeitos da radiação , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/efeitos da radiação , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Células-Tronco Neoplásicas/efeitos da radiação , Paclitaxel , Peptídeos Cíclicos/farmacologia , Peptídeos Cíclicos/uso terapêutico , Fosforilação/efeitos dos fármacos , Neoplasias da Próstata/patologia , Neoplasias da Próstata/radioterapia , Espécies Reativas de Oxigênio/metabolismo , Tapsigargina/farmacologia , Tapsigargina/uso terapêutico , Fator de Crescimento Transformador beta/metabolismo , Resposta a Proteínas não Dobradas/efeitos dos fármacos , Resposta a Proteínas não Dobradas/efeitos da radiação , Raios X , beta Catenina/metabolismo
17.
Free Radic Biol Med ; 90: 261-71, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26627937

RESUMO

We have previously reported that neem limonoids (neem) induce multiple cancer cell death pathways. Here we dissect the underlying mechanisms of neem-induced apoptotic cell death in cancer. We observed that neem-induced caspase activation does not require Bax/Bak channel-mediated mitochondrial outer membrane permeabilization, permeability transition pore, and mitochondrial fragmentation. Neem enhanced mitochondrial DNA and mitochondrial biomass. While oxidative phosphorylation (OXPHOS) Complex-I activity was decreased, the activities of other OXPHOS complexes including Complex-II and -IV were unaltered. Increased reactive oxygen species (ROS) levels were associated with an increase in mitochondrial biomass and apoptosis upon neem exposure. Complex-I deficiency due to the loss of Ndufa1-encoded MWFE protein inhibited neem-induced caspase activation and apoptosis, but cell death induction was enhanced. Complex II-deficiency due to the loss of succinate dehydrogenase complex subunit C (SDHC) robustly decreased caspase activation, apoptosis, and cell death. Additionally, the ablation of Complexes-I, -III, -IV, and -V together did not inhibit caspase activation. Together, we demonstrate that neem limonoids target OXPHOS system to induce cancer cell death, which does not require upregulation or activation of proapoptotic Bcl-2 family proteins.


Assuntos
Apoptose/efeitos dos fármacos , Azadirachta/química , Limoninas/farmacologia , Neoplasias/patologia , Fosforilação Oxidativa , Caspases/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/fisiologia , DNA Mitocondrial/análise , Dinaminas , Complexo I de Transporte de Elétrons/fisiologia , GTP Fosfo-Hidrolases/análise , Células HCT116 , Humanos , Proteínas Associadas aos Microtúbulos/análise , Proteínas de Transporte da Membrana Mitocondrial/fisiologia , Poro de Transição de Permeabilidade Mitocondrial , Proteínas Mitocondriais/análise , Neoplasias/tratamento farmacológico , Proteína Supressora de Tumor p53/fisiologia
18.
Drug Discov Today ; 21(1): 38-47, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26232549

RESUMO

X-chromosome-linked inhibitor of apoptosis protein (XIAP) has an important regulatory role in programmed cell death by inhibiting the caspase cascade. Activation of XIAP-dependent signaling culminates into regulation of multiple cellular processes including apoptosis, innate immunity, epithelial-to-mesenchymal transition, cell migration, invasion, metastasis and differentiation. Although XIAP localizes to the cytosolic compartment, XIAP-mediated cellular signaling encompasses mitochondrial and post-mitochondrial levels. Recent findings demonstrate that XIAP also localizes to mitochondria and regulates mitochondria functions. XIAP acts upstream of mitochondrial cytochrome c release and modulates caspase-dependent apoptosis. The new function of XIAP has potential to enhance mitochondrial membrane permeabilization and other cellular functions controlling cytochrome c release. These findings could exploit the overexpression of XIAP in human tumors for therapeutic benefits.


Assuntos
Mitocôndrias/metabolismo , Membranas Mitocondriais/metabolismo , Neoplasias/metabolismo , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X/metabolismo , Animais , Apoptose/fisiologia , Permeabilidade da Membrana Celular/fisiologia , Citocromos c/metabolismo , Humanos , Transdução de Sinais/fisiologia
19.
Drug Discov Today ; 20(5): 635-43, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25766095

RESUMO

Defective oxidative phosphorylation has a crucial role in the attenuation of mitochondrial function, which confers therapy resistance in cancer. Various factors, including endogenous heat shock proteins (HSPs) and exogenous agents such as dichloroacetate, restore respiratory and other physiological functions of mitochondria in cancer cells. Functional mitochondria might ultimately lead to the restoration of apoptosis in cancer cells that are refractory to current anticancer agents. Here, we summarize the key reasons contributing to mitochondria dysfunction in cancer cells and how restoration of mitochondrial function could be exploited for cancer therapeutics.


Assuntos
Antineoplásicos/uso terapêutico , Ácido Dicloroacético/uso terapêutico , Metabolismo Energético/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Neoplasias/tratamento farmacológico , Animais , Antineoplásicos/química , Ácido Dicloroacético/química , Desenho de Fármacos , Humanos , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Terapia de Alvo Molecular , Neoplasias/metabolismo , Neoplasias/patologia , Fosforilação Oxidativa/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos
20.
Mol Carcinog ; 54(12): 1807-14, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25420488

RESUMO

Lynch syndrome (LS), the most common form of familial CRC predisposition that causes tumor onset at a young age, is characterized by the presence of microsatellite instability (MSI) in tumors due to germline inactivation of mismatch repair (MMR) system. Two MMR genes namely MLH1 and MSH2 account for majority of LS cases while MSH6 and PMS2 may account for a minor proportion. In order to identify MMR genes causing LS in India, we analyzed MSI and determined expression status of the four MMR genes in forty eight suspected LS patient colorectal tumor samples. Though a majority exhibited MSI, only 58% exhibited loss of MMR expression, a significantly low proportion compared to reports from other populations. PCR-DNA sequencing and MLPA-based mutation and exonic deletion/duplication screening respectively, revealed genetic lesions in samples with and without MMR gene expression. Interestingly, tumor samples with and without MMR expression exhibited significant differences with respect to histological (mucin content) and molecular (instability exhibited by mononucleotide microsatellites) features. The study has revealed for the first time a significant proportion of LS tumors not exhibiting loss of MMR expression.


Assuntos
Neoplasias Colorretais Hereditárias sem Polipose/genética , Reparo de Erro de Pareamento de DNA/genética , Expressão Gênica/genética , Adulto , Idoso , Neoplasias Colorretais/genética , Feminino , Humanos , Índia , Masculino , Pessoa de Meia-Idade , Mutação/genética
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