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1.
Natl J Maxillofac Surg ; 14(1): 79-85, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37273426

RESUMEN

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.
Artículo en Inglés | MEDLINE | ID: mdl-35653190

RESUMEN

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.


Asunto(s)
Chaperonina 60 , Neoplasias de la Próstata , Animales , Chaperonina 60/genética , Chaperonina 60/metabolismo , Humanos , Masculino , Ratones , Mitocondrias/genética , Mitocondrias/metabolismo , Proteínas Mitocondriales/genética , Proteínas Mitocondriales/metabolismo , Péptido Hidrolasas/metabolismo , Neoplasias de la Próstata/tratamiento farmacológico , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/metabolismo , Respuesta de Proteína Desplegada
3.
J Family Med Prim Care ; 10(1): 237-242, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34017733

RESUMEN

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.
Artículo en Inglés | MEDLINE | ID: mdl-35004052

RESUMEN

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.
Artículo en Inglés | MEDLINE | ID: mdl-32969251

RESUMEN

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.


Asunto(s)
Predisposición Genética a la Enfermedad , Lupus Eritematoso Sistémico/genética , Metaloproteinasa 2 de la Matriz/genética , Inhibidor Tisular de Metaloproteinasa-2/genética , Adolescente , Adulto , Femenino , Expresión Génica , Marcadores Genéticos , Humanos , Masculino , Metaloproteinasa 2 de la Matriz/sangre , Polimorfismo Genético , Índice de Severidad de la Enfermedad , Inhibidor Tisular de Metaloproteinasa-2/sangre , Adulto Joven
6.
Cancer Res ; 79(7): 1353-1368, 2019 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-30765600

RESUMEN

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.


Asunto(s)
Apoptosomas/fisiología , Negro o Afroamericano , Citocromos c/deficiencia , Mitocondrias/fisiología , Neoplasias de la Próstata/patología , Animales , Línea Celular Tumoral , Citocromos c/metabolismo , Humanos , Masculino , Ratones , Ratones SCID , Membranas Mitocondriales/enzimología , FN-kappa B/metabolismo , Factor Nuclear 1 de Respiración/metabolismo , Fosforilación Oxidativa , Proteínas Proto-Oncogénicas c-myc/metabolismo
7.
Cancer Lett ; 413: 82-93, 2018 01 28.
Artículo en Inglés | MEDLINE | ID: mdl-29107110

RESUMEN

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.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Apoptosis/efectos de los fármacos , Carcinoma Ductal Pancreático/tratamiento farmacológico , Inhibidores de Caspasas/farmacología , Receptores de Hialuranos/metabolismo , Limoninas/farmacología , Mitocondrias/efectos de los fármacos , Células Madre Neoplásicas/efectos de los fármacos , Neoplasias Pancreáticas/tratamiento farmacológico , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/metabolismo , Carcinoma Ductal Pancreático/patología , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Desoxicitidina/análogos & derivados , Desoxicitidina/farmacología , Relación Dosis-Respuesta a Droga , Humanos , Mitocondrias/metabolismo , Mitocondrias/patología , Mutación , Células Madre Neoplásicas/metabolismo , Células Madre Neoplásicas/patología , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patología , Especies Reactivas de Oxígeno/metabolismo , Factores de Tiempo , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo , Gemcitabina
8.
Sci Rep ; 7(1): 10451, 2017 09 05.
Artículo en Inglés | MEDLINE | ID: mdl-28874842

RESUMEN

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.


Asunto(s)
Antibióticos Antineoplásicos/farmacología , Doxorrubicina/farmacología , Metabolismo Energético/efectos de los fármacos , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Neoplasias de la Próstata/metabolismo , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Flavina-Adenina Dinucleótido/metabolismo , Humanos , Masculino , Microscopía Fluorescente , NADP/metabolismo , Imagen Óptica , Oxidación-Reducción , Fosforilación Oxidativa/efectos de los fármacos , Estrés Oxidativo , Especies Reactivas de Oxígeno , Triptófano/metabolismo
9.
Biochim Biophys Acta Rev Cancer ; 1867(1): 58-66, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27988298

RESUMEN

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.


Asunto(s)
Apoptosis/fisiología , Estrés del Retículo Endoplásmico/fisiología , Retículo Endoplásmico/patología , Mitocondrias/patología , Neoplasias/patología , Respuesta de Proteína Desplegada/fisiología , Animales , Humanos , Pliegue de Proteína , Transducción de Señal/fisiología
10.
Front Biosci (Schol Ed) ; 9(1): 154-164, 2017 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-27814581

RESUMEN

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.


Asunto(s)
Negro o Afroamericano , Disparidades en el Estado de Salud , Mitocondrias/genética , Mitocondrias/metabolismo , Neoplasias de la Próstata/etnología , Neoplasias de la Próstata/fisiopatología , Población Blanca , ADN Mitocondrial/genética , ADN Mitocondrial/metabolismo , Humanos , Masculino , Fosforilación Oxidativa , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/metabolismo , Estados Unidos
11.
Asian Pac J Cancer Prev ; 17(7): 3043-51, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27509927

RESUMEN

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.


Asunto(s)
Neoplasias Hematológicas/metabolismo , Metaloproteinasas de la Matriz/metabolismo , Animales , Carcinogénesis/efectos de los fármacos , Carcinogénesis/metabolismo , Progresión de la Enfermedad , Matriz Extracelular/efectos de los fármacos , Matriz Extracelular/metabolismo , Neoplasias Hematológicas/tratamiento farmacológico , Humanos , Inhibidores de la Metaloproteinasa de la Matriz/farmacología , Inhibidores de la Metaloproteinasa de la Matriz/uso terapéutico
13.
Asian Pac J Cancer Prev ; 17(3): 1519-29, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27039800

RESUMEN

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.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Crisis Blástica/metabolismo , Células de la Médula Ósea/metabolismo , Leucemia Mieloide Aguda/metabolismo , Metaloproteinasa 2 de la Matriz/metabolismo , Metaloproteinasa 9 de la Matriz/metabolismo , Síndromes Mielodisplásicos/metabolismo , Biomarcadores de Tumor/genética , Crisis Blástica/patología , Células de la Médula Ósea/patología , Estudios de Casos y Controles , Ensayo de Inmunoadsorción Enzimática , Estudios de Seguimiento , Humanos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patología , Metaloproteinasa 2 de la Matriz/genética , Metaloproteinasa 9 de la Matriz/genética , Síndromes Mielodisplásicos/genética , Síndromes Mielodisplásicos/patología , Clasificación del Tumor , Estadificación de Neoplasias , Pronóstico , ARN Mensajero/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Índice de Severidad de la Enfermedad
14.
Br J Cancer ; 114(10): 1090-100, 2016 05 10.
Artículo en Inglés | MEDLINE | ID: mdl-27115471

RESUMEN

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.


Asunto(s)
Ácido Dicloroacético/farmacología , Proteínas de Choque Térmico/metabolismo , Mitocondrias/efectos de los fármacos , Neoplasias de la Próstata/etnología , Neoplasias de la Próstata/metabolismo , Negro o Afroamericano , Apoptosis/efectos de los fármacos , Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Masculino , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Mitocondrias/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Estados Unidos
15.
Mol Oncol ; 10(7): 949-65, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27106131

RESUMEN

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.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Apoptosis , Citoesqueleto/metabolismo , Mitocondrias/metabolismo , Neoplasias de la Próstata/tratamiento farmacológico , Neoplasias de la Próstata/metabolismo , Respuesta de Proteína Desplegada , Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Apoptosis/efectos de los fármacos , Apoptosis/efectos de la radiación , Caspasas/metabolismo , Puntos de Control del Ciclo Celular/efectos de los fármacos , Puntos de Control del Ciclo Celular/efectos de la radiación , Muerte Celular/efectos de los fármacos , Muerte Celular/efectos de la radiación , Línea Celular Tumoral , Citoesqueleto/efectos de los fármacos , Citoesqueleto/efectos de la radiación , Activación Enzimática/efectos de los fármacos , Fase G1/efectos de los fármacos , Fase G1/efectos de la radiación , Fase G2/efectos de los fármacos , Fase G2/efectos de la radiación , Proteínas HSP70 de Choque Térmico/metabolismo , Humanos , Interferón gamma/metabolismo , Interleucina-8/metabolismo , Masculino , Metaloproteinasas de la Matriz/metabolismo , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Potencial de la Membrana Mitocondrial/efectos de la radiación , Mitocondrias/efectos de los fármacos , Mitocondrias/efectos de la radiación , Células Madre Neoplásicas/efectos de los fármacos , Células Madre Neoplásicas/metabolismo , Células Madre Neoplásicas/patología , Células Madre Neoplásicas/efectos de la radiación , Paclitaxel , Péptidos Cíclicos/farmacología , Péptidos Cíclicos/uso terapéutico , Fosforilación/efectos de los fármacos , Neoplasias de la Próstata/patología , Neoplasias de la Próstata/radioterapia , Especies Reactivas de Oxígeno/metabolismo , Tapsigargina/farmacología , Tapsigargina/uso terapéutico , Factor de Crecimiento Transformador beta/metabolismo , Respuesta de Proteína Desplegada/efectos de los fármacos , Respuesta de Proteína Desplegada/efectos de la radiación , Rayos X , beta Catenina/metabolismo
17.
Free Radic Biol Med ; 90: 261-71, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26627937

RESUMEN

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.


Asunto(s)
Apoptosis/efectos de los fármacos , Azadirachta/química , Limoninas/farmacología , Neoplasias/patología , Fosforilación Oxidativa , Caspasas/metabolismo , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/fisiología , ADN Mitocondrial/análisis , Dinaminas , Complejo I de Transporte de Electrón/fisiología , GTP Fosfohidrolasas/análisis , Células HCT116 , Humanos , Proteínas Asociadas a Microtúbulos/análisis , Proteínas de Transporte de Membrana Mitocondrial/fisiología , Poro de Transición de la Permeabilidad Mitocondrial , Proteínas Mitocondriales/análisis , Neoplasias/tratamiento farmacológico , Proteína p53 Supresora de Tumor/fisiología
18.
Drug Discov Today ; 21(1): 38-47, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26232549

RESUMEN

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.


Asunto(s)
Mitocondrias/metabolismo , Membranas Mitocondriales/metabolismo , Neoplasias/metabolismo , Proteína Inhibidora de la Apoptosis Ligada a X/metabolismo , Animales , Apoptosis/fisiología , Permeabilidad de la Membrana Celular/fisiología , Citocromos c/metabolismo , Humanos , Transducción de Señal/fisiología
19.
Drug Discov Today ; 20(5): 635-43, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25766095

RESUMEN

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.


Asunto(s)
Antineoplásicos/uso terapéutico , Ácido Dicloroacético/uso terapéutico , Metabolismo Energético/efectos de los fármacos , Mitocondrias/efectos de los fármacos , Neoplasias/tratamiento farmacológico , Animales , Antineoplásicos/química , Ácido Dicloroacético/química , Diseño de Fármacos , Humanos , Mitocondrias/metabolismo , Mitocondrias/patología , Terapia Molecular Dirigida , Neoplasias/metabolismo , Neoplasias/patología , Fosforilación Oxidativa/efectos de los fármacos , Transducción de Señal/efectos de los fármacos
20.
Mol Carcinog ; 54(12): 1807-14, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25420488

RESUMEN

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.


Asunto(s)
Neoplasias Colorrectales Hereditarias sin Poliposis/genética , Reparación de la Incompatibilidad de ADN/genética , Expresión Génica/genética , Adulto , Anciano , Neoplasias Colorrectales/genética , Femenino , Humanos , India , Masculino , Persona de Mediana Edad , Mutación/genética
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