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1.
J Minim Access Surg ; 18(4): 533-538, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35046176

RESUMEN

Aim: Laparoscopic CBD exploration (LCBDE) for Common bile duct (CBD) stones with laparoscopic cholecystectomy (LC) is an alternative to open CBD exploration, in patients with failed endoscopic retrograde cholangio-pancreatography (ERCP). It is being performed at few centres with adequate surgical expertise. Herein, we present our experience of LCBDE with LC over a period of 10 years. Patients and Methods: A retrospective analysis of prospectively recorded data of 121 consecutive patients was performed from February 2010 to November 2019, who underwent LC and LCBDE by choledochotomy in a single surgical unit. These included all patients with failed pre-operative ERCP. Results: Out of 121 patients, LCBDE successfully cleared the CBD in 118, and three patients were converted to open surgery. All these patients underwent choledochotomy for adequate exploration of CBD. T-tube closure of CBD was performed in 103 patients and removed after a mean of 14.6 ± 2.4 days. Primary closure was performed in 15 patients. The mean hospital stay post-procedure was 3.4 ± 0.7 days. Complete ductal clearance was achieved in 115 patients, and residual stone fragments reported in three patients were removed by ERCP. None of the patients experienced biliary peritonitis, biliary fistula, pancreatitis or cholangitis. There was no 30-day mortality and no recurrent stones reported with a mean follow-up of 12.4 ± 3.9 months. Conclusion: With adequate surgical expertise, LCBDE is a feasible alternative to open surgery for CBD stones after failed ERCP with early recovery and low morbidity.

2.
J Biol Chem ; 291(31): 16263-70, 2016 07 29.
Artículo en Inglés | MEDLINE | ID: mdl-27246849

RESUMEN

Extensive desmoplasia is a prominent pathological characteristic of pancreatic cancer (PC) that not only impacts tumor development, but therapeutic outcome as well. Recently, we demonstrated a novel role of MYB, an oncogenic transcription factor, in PC growth and metastasis. Here we studied its effect on pancreatic tumor histopathology and associated molecular and biological mechanisms. Tumor-xenografts derived from orthotopic-inoculation of MYB-overexpressing PC cells exhibited far-greater desmoplasia in histological analyses compared with those derived from MYB-silenced PC cells. These findings were further confirmed by immunostaining of tumor-xenograft sections with collagen-I, fibronectin (major extracellular-matrix proteins), and α-SMA (well-characterized marker of myofibroblasts or activated pancreatic stellate cells (PSCs)). Likewise, MYB-overexpressing PC cells provided significantly greater growth benefit to PSCs in a co-culture system as compared with the MYB-silenced cells. Interrogation of deep-sequencing data from MYB-overexpressing versus -silenced PC cells identified Sonic-hedgehog (SHH) and Adrenomedullin (ADM) as two differentially-expressed genes among others, which encode for secretory ligands involved in tumor-stromal cross-talk. In-silico analyses predicted putative MYB-binding sites in SHH and ADM promoters, which was later confirmed by chromatin-immunoprecipitation. A cooperative role of SHH and ADM in growth promotion of PSCs was confirmed in co-culture by using their specific-inhibitors and exogenous recombinant-proteins. Importantly, while SHH acted exclusively in a paracrine fashion on PSCs and influenced the growth of PC cells only indirectly, ADM could directly impact the growth of both PC cells and PSCs. In summary, we identified MYB as novel regulator of pancreatic tumor desmoplasia, which is suggestive of its diverse roles in PC pathobiology.


Asunto(s)
Adrenomedulina/biosíntesis , Regulación Neoplásica de la Expresión Génica , Proteínas Hedgehog/biosíntesis , Proteínas Oncogénicas v-myb/metabolismo , Neoplasias Pancreáticas/metabolismo , Comunicación Paracrina , Elementos de Respuesta , Transcripción Genética , Regulación hacia Arriba , Adrenomedulina/genética , Animales , Línea Celular Tumoral , Proteínas Hedgehog/genética , Xenoinjertos , Humanos , Ratones , Trasplante de Neoplasias , Proteínas Oncogénicas v-myb/genética , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patología , Células Estrelladas Pancreáticas/metabolismo , Células Estrelladas Pancreáticas/patología
3.
Br J Cancer ; 116(5): 609-619, 2017 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-28152544

RESUMEN

BACKGROUND: Chemoresistance is a significant clinical problem in pancreatic cancer (PC) and underlying molecular mechanisms still remain to be completely understood. Here we report a novel exosome-mediated mechanism of drug-induced acquired chemoresistance in PC cells. METHODS: Differential ultracentrifugation was performed to isolate extracellular vesicles (EVs) based on their size from vehicle- or gemcitabine-treated PC cells. Extracellular vesicles size and subtypes were determined by dynamic light scattering and marker profiling, respectively. Gene expression was examined by qRT-PCR and/or immunoblot analyses, and direct targeting of DCK by miR-155 was confirmed by dual-luciferase 3'-UTR reporter assay. Flow cytometry was performed to examine the apoptosis indices and reactive oxygen species (ROS) levels in PC cells using specific dyes. Cell viability was determined using the WST-1 assay. RESULTS: Conditioned media (CM) from gemcitabine-treated PC cells (Gem-CM) provided significant chemoprotection to subsequent gemcitabine toxicity and most of the chemoresistance conferred by Gem-CM resulted from its EVs fraction. Sub-fractionation grouped EVs into distinct subtypes based on size distribution and marker profiles, and exosome (Gem-Exo) was the only sub-fraction that imparted chemoresistance. Gene expression analyses demonstrated upregulation of SOD2 and CAT (ROS-detoxifying genes), and downregulation of DCK (gemcitabine-metabolising gene) in Gem-Exo-treated cells. SOD/CAT upregulation resulted, at least in part, from exosome-mediated transfer of their transcripts and they suppressed basal and gemcitabine-induced ROS production, and partly promoted chemoresistance. DCK downregulation occurred through exosome-delivered miR-155 and either the functional suppression of miR-155 or restoration of DCK led to marked abrogation of Gem-Exo-mediated chemoresistance. CONCLUSIONS: Together, these findings establish a novel role of exosomes in mediating the acquired chemoresistance of PC.


Asunto(s)
Catalasa/genética , Desoxicitidina Quinasa/genética , Resistencia a Antineoplásicos , Exosomas/fisiología , MicroARNs/genética , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Superóxido Dismutasa/genética , Regiones no Traducidas 3' , Línea Celular Tumoral , Desoxicitidina/análogos & derivados , Desoxicitidina/farmacología , Dispersión Dinámica de Luz , Exosomas/genética , Exosomas/metabolismo , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Especies Reactivas de Oxígeno/metabolismo , Gemcitabina
4.
Nutr Cancer ; 69(6): 932-942, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28718667

RESUMEN

SCOPE: Hydroxytyrosol (HT), a polyphenol from olives, is a potential anticancer agent. This study was designed to evaluate the anticancer activity of HT against prostate cancer cells, and the mechanism thereof. METHODS AND RESULTS: Treatment of LNCaP and C4-2 prostate cancer cells with HT resulted in a dose-dependent inhibition of proliferation. This was in contrast to HT's ineffectiveness against normal prostate epithelial cells RWPE1 and PWLE2, suggesting cancer-cell-specific effect. HT induced G1/S cell cycle arrest, with inhibition of cyclins D1/E and cdk2/4 and induction of inhibitory p21/p27. HT also induced apoptosis, as confirmed by flow cytometry, caspase activation, PARP cleavage, and BAX/Bcl-2 ratio. It inhibited the phosphorylation of Akt/STAT3, and induced cytoplasmic retention of NF-κB, which may explain its observed effects. Finally, HT inhibited androgen receptor (AR) expression and the secretion of AR-responsive prostate-specific antigen. CONCLUSION: Castration-resistant prostate cancers retain AR signaling and are often marked by activated Akt, NF-κB, and STAT3 signaling. Our results establish a pleiotropic activity of HT against these oncogenic signaling pathways. Combined with its nontoxic effects against normal cells, our results support further testing of HT for prostate cancer therapy.


Asunto(s)
Antioxidantes/farmacología , Apoptosis/efectos de los fármacos , Puntos de Control del Ciclo Celular/efectos de los fármacos , Alcohol Feniletílico/análogos & derivados , Caspasa 3/genética , Caspasa 3/metabolismo , Caspasa 7/genética , Caspasa 7/metabolismo , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Ciclina D1/antagonistas & inhibidores , Ciclina D1/genética , Ciclina D1/metabolismo , Ciclina E/antagonistas & inhibidores , Ciclina E/genética , Ciclina E/metabolismo , Células Epiteliales/citología , Células Epiteliales/efectos de los fármacos , Células Epiteliales/metabolismo , Humanos , Masculino , FN-kappa B/genética , FN-kappa B/metabolismo , Proteínas Oncogénicas/antagonistas & inhibidores , Proteínas Oncogénicas/genética , Proteínas Oncogénicas/metabolismo , Alcohol Feniletílico/farmacología , Fosforilación , Antígeno Prostático Específico/genética , Antígeno Prostático Específico/metabolismo , Neoplasias de la Próstata , Proteínas Proto-Oncogénicas c-akt/genética , Proteínas Proto-Oncogénicas c-akt/metabolismo , Receptores Androgénicos/genética , Receptores Androgénicos/metabolismo , Factor de Transcripción STAT3/genética , Factor de Transcripción STAT3/metabolismo , Transducción de Señal , Proteína X Asociada a bcl-2/genética , Proteína X Asociada a bcl-2/metabolismo
5.
Int J Mol Sci ; 18(4)2017 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-28383487

RESUMEN

Pancreatic cancer (PC) continues to rank among the most lethal cancers. The consistent increase in incidence and mortality has made it the seventh leading cause of cancer-associated deaths globally and the third in the United States. The biggest challenge in combating PC is our insufficient understanding of the molecular mechanism(s) underlying its complex biology. Studies during the last several years have helped identify several putative factors and events, both genetic and epigenetic, as well as some deregulated signaling pathways, with implications in PC onset and progression. In this review article, we make an effort to summarize our current understanding of molecular and cellular events involved in the pathogenesis of pancreatic malignancy. Specifically, we provide up-to-date information on the genetic and epigenetic changes that occur during the initiation and progression of PC and their functional involvement in the pathogenic processes. We also discuss the impact of the tumor microenvironment on the molecular landscape of PC and its role in aggressive disease progression. It is envisioned that a better understanding of these molecular factors and the mechanisms of their actions can help unravel novel diagnostic and prognostic biomarkers and can also be exploited for future targeted therapies.


Asunto(s)
Biomarcadores de Tumor/genética , Epigénesis Genética , Mutación , Neoplasias Pancreáticas/patología , Progresión de la Enfermedad , Regulación Neoplásica de la Expresión Génica , Predisposición Genética a la Enfermedad , Humanos , Terapia Molecular Dirigida , Neoplasias Pancreáticas/genética , Microambiente Tumoral
6.
Carcinogenesis ; 37(11): 1052-1061, 2016 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-27609457

RESUMEN

The poor clinical outcome of pancreatic cancer (PC) is largely attributed to its aggressive nature and refractoriness to currently available therapeutic modalities. We previously reported antitumor efficacy of honokiol (HNK), a phytochemical isolated from various parts of Magnolia plant, against PC cells in short-term in vitro growth assays. Here, we report that HNK reduces plating efficiency and anchorage-independent growth of PC cells and suppresses their migration and invasiveness. Furthermore, significant inhibition of pancreatic tumor growth by HNK is observed in orthotopic mouse model along with complete-blockage of distant metastases. Histological examination suggests reduced desmoplasia in tumors from HNK-treated mice, later confirmed by immunohistochemical analyses of myofibroblast and extracellular matrix marker proteins (α-SMA and collagen I, respectively). At the molecular level, HNK treatment leads to decreased expression of sonic hedgehog (SHH) and CXCR4, two established mediators of bidirectional tumor-stromal cross-talk, both in vitro and in vivo . We also show that the conditioned media (CM) from HNK-treated PC cells have little growth-inducing effect on pancreatic stellate cells (PSCs) that could be regained by the addition of exogenous recombinant SHH. Moreover, pretreatment of CM of vehicle-treated PC cells with SHH-neutralizing antibody abolishes their growth-inducing potential on PSCs. Likewise, HNK-treated PC cells respond poorly to CM from PSCs due to decreased CXCR4 expression. Lastly, we show that the transfection of PC cells with constitutively active IKKß mutant reverses the suppressive effect of HNK on nuclear factor-kappaB activation and partially restores CXCR4 and SHH expression. Taken together, these findings suggest that HNK interferes with tumor-stromal cross-talk via downregulation of CXCR4 and SHH and decreases pancreatic tumor growth and metastasis.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Compuestos de Bifenilo/farmacología , Lignanos/farmacología , Neoplasias Hepáticas Experimentales/prevención & control , Neoplasias Pulmonares/prevención & control , Neoplasias Pancreáticas/tratamiento farmacológico , Animales , Antineoplásicos Fitogénicos/uso terapéutico , Compuestos de Bifenilo/uso terapéutico , Comunicación Celular , Línea Celular Tumoral , Regulación hacia Abajo , Femenino , Expresión Génica/efectos de los fármacos , Proteínas Hedgehog/genética , Proteínas Hedgehog/metabolismo , Humanos , Lignanos/uso terapéutico , Neoplasias Hepáticas Experimentales/secundario , Neoplasias Pulmonares/secundario , Ratones , Neoplasias Pancreáticas/patología , Receptores CXCR4/genética , Receptores CXCR4/metabolismo , Microambiente Tumoral , Ensayos Antitumor por Modelo de Xenoinjerto
7.
Br J Cancer ; 113(12): 1694-703, 2015 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-26657649

RESUMEN

BACKGROUND: MYB encodes for a transcription factor regulating the expression of a wide array of genes involved in cellular functions. It is reported to be amplified in a sub-set of pancreatic cancer (PC) cases; however, its pathobiological association has remained unclear thus far. METHODS: Expression of MYB and other cellular proteins was analysed by immunoblot or qRT-PCR analyses. MYB was stably overexpressed in non-expressing (BxPC3) and silenced in highly expressing (MiaPaCa and Panc1) PC cells. Effect on growth was analysed by automated cell counting at 24-h interval. Cell-cycle progression and apoptotic indices of PC cells with altered MYB expression were measured through flow cytometry upon staining with respective biomarkers. Cell motility/invasion was examined in a Boyden's chamber assay using non-coated or Matrigel-coated membranes. Effect on tumorigenicity and metastatic potential was examined by non-invasive imaging and through end-point measurements of luciferase-tagged MYB-altered PC implanted in the pancreas of nude mice. RESULTS: MYB was aberrantly expressed in all malignant cases of pancreas, whereas remained undetectable in normal pancreas. All the tested established PC cell lines except BxPC3 also exhibited MYB expression. Forced expression of MYB in BxPC3 cells promoted their growth, cell-cycle progression, survival and malignant behaviour, whereas its silencing in MiaPaCa and Panc1 cells produced converse effects. More importantly, ectopic MYB expression was sufficient to confer tumorigenic and metastatic capabilities to non-tumorigenic BxPC3 cells, while its silencing resulted in significant loss of the same in MYB-overexpressing cells as demonstrated in orthotopic mouse model. We also identified several MYB-regulated genes in PC cells that might potentially mediate its effect on tumour growth and metastasis. CONCLUSIONS: MYB is aberrantly overexpressed in PC cells and acts as a key determinant of pancreatic tumour growth and metastasis.


Asunto(s)
División Celular/genética , Genes myb , Metástasis de la Neoplasia/genética , Neoplasias Pancreáticas/patología , Animales , Ciclo Celular , Xenoinjertos , Humanos , Ratones , Neoplasias Pancreáticas/genética
8.
Br J Cancer ; 113(4): 660-8, 2015 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-26247574

RESUMEN

BACKGROUND: Previously, miR-345 was identified as one of the most significantly downregulated microRNAs in pancreatic cancer (PC); however, its functional significance remained unexplored. METHODS: miR-345 was overexpressed in PC cells by stable transfection, and its effect on growth, apoptosis and mitochondrial-membrane potential was examined by WST-1, Hoechst-33342/Annexin-V, and JC-1 staining, respectively. Gene expression was examined by quantitative reverse-transcription-PCR and/or immunoblotting, and subcellular fractions prepared and caspase-3/7 activity determined by commercially available kits. miR-345 target validation was performed by mutational analysis and luciferase-reporter assay. RESULTS: miR-345 is significantly downregulated in PC tissues and cell lines relative to normal pancreatic cells, and its expression decreases gradually in PC progression model cell lines. Forced expression of miR-345 results in reduced growth of PC cells because of the induction of apoptosis, accompanied by a loss in mitochondrial membrane potential, cytochrome-c release, caspases-3/7 activation, and PARP-1 cleavage, as well as mitochondrial-to-nuclear translocation of apoptosis-inducing factor. These effects could be reversed by the treatment of miR-345-overexpressing PC cells with anti-miR-345 oligonucleotides. BCL2 was characterised as a novel target of miR-345 and its forced-expression abrogated the effects of miR-345 in PC cells. CONCLUSIONS: miR-345 downregulation confers apoptosis resistance to PC cells, and its restoration could be exploited for therapeutic benefit.


Asunto(s)
Apoptosis/genética , Caspasa 3/genética , Caspasa 7/genética , MicroARNs/genética , Neoplasias Pancreáticas/genética , Transducción de Señal/genética , Línea Celular Tumoral , Núcleo Celular/genética , Citocromos c/genética , Regulación hacia Abajo/genética , Regulación Neoplásica de la Expresión Génica/genética , Humanos , Potencial de la Membrana Mitocondrial/genética , Mitocondrias/genética , Poli(ADP-Ribosa) Polimerasa-1 , Poli(ADP-Ribosa) Polimerasas , Proteína X Asociada a bcl-2/genética
9.
Nanomedicine ; 11(5): 1265-75, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25804413

RESUMEN

Ultraviolet (UV)-B radiation from the sun is an established etiological cause of skin cancer, which afflicts more than a million lives each year in the United States alone. Here, we tested the chemopreventive efficacy of silver-nanoparticles (AgNPs) against UVB-irradiation-induced DNA damage and apoptosis in human immortalized keratinocytes (HaCaT). AgNPs were synthesized by reduction-chemistry and characterized for their physicochemical properties. AgNPs were well tolerated by HaCaT cells and their pretreatment protected them from UVB-irradiation-induced apoptosis along with significant reduction in cyclobutane-pyrimidine-dimer formation. Moreover, AgNPs pre-treatment led to G1-phase cell-cycle arrest in UVB-irradiated HaCaT cells. AgNPs were efficiently internalized in UVB-irradiated cells and localized into cytoplasmic and nuclear compartments. Furthermore, we observed an altered expression of various genes involved in cell-cycle, apoptosis and nucleotide-excision repair in HaCaT cells treated with AgNPs prior to UVB-irradiation. Together, these findings provide support for potential utility of AgNPs as novel chemopreventive agents against UVB-irradiation-induced skin carcinogenesis. FROM THE CLINICAL EDITOR: Excessive exposure to the sun is known to increase the risk of skin cancer due to DNA damage. In this work, the authors tested the use of silver nanoparticles as protective agents against ultraviolet radiation. The positive results may open a door for the use of silver nanoparticle as novel agents in the future.


Asunto(s)
Anticarcinógenos/farmacología , Apoptosis/efectos de los fármacos , Queratinocitos/efectos de los fármacos , Queratinocitos/efectos de la radiación , Nanopartículas del Metal , Plata/farmacología , Anticarcinógenos/química , Línea Celular , Daño del ADN/efectos de los fármacos , Reparación del ADN , Humanos , Queratinocitos/patología , Nanopartículas del Metal/química , Nanopartículas del Metal/ultraestructura , Plata/química , Neoplasias Cutáneas/prevención & control , Rayos Ultravioleta
10.
J Biol Chem ; 288(29): 21197-21207, 2013 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-23740244

RESUMEN

Recently, we have shown that CXCL12/CXCR4 signaling plays an important role in gemcitabine resistance of pancreatic cancer (PC) cells. Here, we explored the effect of gemcitabine on this resistance mechanism. Our data demonstrate that gemcitabine induces CXCR4 expression in two PC cell lines (MiaPaCa and Colo357) in a dose- and time-dependent manner. Gemcitabine-induced CXCR4 expression is dependent on reactive oxygen species (ROS) generation because it is abrogated by pretreatment of PC cells with the free radical scavenger N-acetyl-L-cysteine. CXCR4 up-regulation by gemcitabine correlates with time-dependent accumulation of NF-κB and HIF-1α in the nucleus. Enhanced binding of NF-κB and HIF-1α to the CXCR4 promoter is observed in gemcitabine-treated PC cells, whereas their silencing by RNA interference causes suppression of gemcitabine-induced CXCR4 expression. ROS induction upon gemcitabine treatment precedes the nuclear accumulation of NF-κB and HIF-1α, and suppression of ROS diminishes these effects. The effect of ROS on NF-κB and HIF-1α is mediated through activation of ERK1/2 and Akt, and their pharmacological inhibition also suppresses gemcitabine-induced CXCR4 up-regulation. Interestingly, our data demonstrate that nuclear accumulation of NF-κB results from phosphorylation-induced degradation of IκBα, whereas HIF-1α up-regulation is NF-κB-dependent. Lastly, our data demonstrate that gemcitabine-treated PC cells are more motile and exhibit significantly greater invasiveness against a CXCL12 gradient. Together, these findings reinforce the role of CXCL12/CXCR4 signaling in gemcitabine resistance and point toward an unintended and undesired effect of chemotherapy.


Asunto(s)
Desoxicitidina/análogos & derivados , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , FN-kappa B/metabolismo , Neoplasias Pancreáticas/patología , Especies Reactivas de Oxígeno/metabolismo , Receptores CXCR4/genética , Regulación hacia Arriba/efectos de los fármacos , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Movimiento Celular/genética , Desoxicitidina/efectos adversos , Desoxicitidina/farmacología , Activación Enzimática/efectos de los fármacos , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Invasividad Neoplásica , Neoplasias Pancreáticas/enzimología , Neoplasias Pancreáticas/genética , Proteínas Proto-Oncogénicas c-akt/metabolismo , Receptores CXCR4/metabolismo , Factor de Transcripción ReIA/metabolismo , Transcripción Genética/efectos de los fármacos , Regulación hacia Arriba/genética , Gemcitabina
11.
J Food Sci Technol ; 51(2): 233-44, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24493880

RESUMEN

The bacteriocin susceptibility of Listeria monocytogenes MTCC 657, Enterococcus faecium DSMZ 20477, E. faecium VRE, and E. faecalis ATCC 29212 and their corresponding bacteriocin resistant variants was assessed. The single and combined effect of nisin and pediocin 34 and enterocin FH99 bacteriocins produced by Pediococcus pentosaceus 34, and E. faecium FH99, respectively, was determined. Pediocin34 proved to be more effective in inhibiting L. monocytogenes MTCC 657. A greater antibacterial effect was observed against E. faecium DSMZ 20477 and E. faecium (VRE) when the a combination of nisin, pediocin 34 and enterocin FH99 were used whereas in case of L. monocytogenes MTCC 657 a combination of pediocin 34 and enterocin FH99 was more effective in reducing the survival of pathogen. Bacteriocin cross-resistance and the antibiotic susceptibility of wild type and their corresponding resistant variants were assessed and results showed that resistance to a bacteriocin may extend to other bacteriocins within the same class and also the acquired resistance to bacteriocins can modify the antibiotic susceptibility/resistance profile of the bacterial species used in the study. According to the hydrophobicity nisin resistant variant of L. monocytogenes was more hydrophobic (p < 0.001), whereas the pediocin 34 and enterocin FH99 resistant variants were less hydrophobic than the wild type strain. Nisin, pediocin 34 and enterocin FH99 resistant variants of E. faecium DSMZ 20477 and E. faecium VRE were less hydrophobic than their wild type counterparts. Nisin resistant E. faecalis ATCC 29212 was less hydrophobic than its wild type counterpart.

12.
J Biol Chem ; 287(46): 39115-24, 2012 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-22995914

RESUMEN

Recent evidence suggests a major role of tumor-stromal interactions in pancreatic cancer pathobiology. The chemokine CXCL12 (stromal cell-derived factor 1 (SDF-1)), abundantly produced by stromal cells, promotes progression, metastasis, and chemoresistance of pancreatic cancer cells. On the other hand, pancreatic tumor cell-derived sonic hedgehog (SHH) acts predominantly on stromal cells to induce desmoplasia and, thus, has a paracrine effect on tumorigenesis and therapeutic outcome. In this study, we examined the association between these two proteins of pathological significance in pancreatic cancer. Our data demonstrate that CXCL12 leads to a dose- and time-dependent up-regulation of SHH in pancreatic cancer cells. CXCL12-induced SHH up-regulation is specifically mediated through the receptor CXCR4 and is dependent on the activation of downstream Akt and ERK signaling pathways. Both Akt and ERK cooperatively promote nuclear accumulation of NF-κB by inducing the phosphorylation and destabilization of its inhibitory protein, IκB-α. Using dominant negative IκB-α, a SHH promoter (deletion mutant) reporter, and chromatin immunoprecipitation assays, we demonstrate that CXCL12 exposure enhances direct binding of NF-κB to the SHH promoter and that suppression of NF-κB activation abrogates CXCL12-induced SHH expression. Finally, our data demonstrate a strong correlative expression of CXCR4 and SHH in human pancreatic cancer tissues, whereas their expression is not observed in the normal pancreas. Altogether, our data reveal a novel mechanism underlying aberrant SHH expression in pancreatic cancer and identify a molecular link facilitating bidirectional tumor-stromal interactions.


Asunto(s)
Quimiocina CXCL12/metabolismo , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Regulación Neoplásica de la Expresión Génica , Proteínas Hedgehog/metabolismo , FN-kappa B/metabolismo , Neoplasias Pancreáticas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Receptores CXCR4/metabolismo , Línea Celular Tumoral , Núcleo Celular/metabolismo , Quimiocinas/metabolismo , Citoplasma/metabolismo , Genes Dominantes , Humanos , Modelos Biológicos , Regiones Promotoras Genéticas , Transducción de Señal
13.
JCO Clin Cancer Inform ; 7: e2300182, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37897263

RESUMEN

PURPOSE: There is raising interest to implement electronic patient-reported outcomes (ePROs) for symptom monitoring to enhance the quality of cancer care. Step 1 of the Texas Two-Step Study demonstrated successful implementation of an ePRO system in >200 sites of service of a large community oncology practice. We now report step 2 of this study which evaluates the impact of ePROs on outcomes among patients enrolled in the Centers for Medicare & Medicaid Services' Oncology Care Model (OCM) program. METHODS: This observational study focused on patients with metastatic cancer enrolled in OCM at large community oncology practice located in Texas between July 2020 and December 2020. Patients who completed ≥1 survey via the ePRO tool were included in the study group and were propensity score matched with patients in a control group. Adverse events (AEs; hospitalizations, emergency department visits, deaths) and total cost of care were a priori study outcomes. Mann-Whitney U and chi-square tests compared continuous and categorical variables, respectively, with multivariable logistic regression for adjustment of covariates. RESULTS: Of 831 patients with metastatic cancer, 458 matched patients (229/group) were identified, with 52% male and a mean age of 74 years. Mean total AEs were lower in the study group compared with control (0.98 v 1.41; P = .007), with decreased hospitalizations (20% v 32.5%; P = .002), emergency visits (38.4% v 42.3%; P > .05), and deaths (11.8% v 16.6%; P > .05). Average number of hospitalizations was lower (0.28 v 0.52; P = .003) with reduced mean duration of hospitalizations (1.9 vs 3.2 d; P = .03). The total cost of care was reduced by an average of $1,146 per member per month. CONCLUSION: Symptom monitoring with ePROs improved quality and value of cancer care delivery by reducing hospitalizations, emergency visits, and deaths while lowering cost of care in a large oncology practice.


Asunto(s)
Medicare , Neoplasias , Humanos , Masculino , Anciano , Estados Unidos , Femenino , Texas/epidemiología , Hospitalización , Neoplasias/diagnóstico , Neoplasias/terapia , Medición de Resultados Informados por el Paciente , Electrónica
14.
JAMA Otolaryngol Head Neck Surg ; 149(10): 912-918, 2023 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-37651149

RESUMEN

Importance: The US Food and Drug Administration approved immune checkpoint inhibitors (immunotherapy) for select cases of head and neck squamous cell carcinoma (HNSCC) in 2016. However, it is unclear whether there are clinical or sociodemographic differences among patients receiving immunotherapy as part of their care. Given the known disparities in head and neck cancer care, we hypothesized that there are differences in receipt of immunotherapy among patients with HNSCC based on clinical and nonclinical characteristics. Objective: To characterize clinical and nonclinical factors associated with receipt of immunotherapy among older patients with HNSCC. Design, Setting, and Participants: This retrospective cohort study included patients 65 years or older diagnosed with HNSCC (n = 4860) in a community oncology care setting. Electronic health records from Navigating Cancer were assessed from January 1, 2017, to April 30, 2022. Main Outcomes and Measures: Multivariable logistic regression was used to characterize clinical (tumor stage [localized vs advanced] and anatomical subsite [oropharyngeal vs nonoropharyngeal]) and nonclinical (age, smoking history, race and ethnicity, sex, and marital status) factors associated with receipt of immunotherapy. Results: In the study cohort of 4860 patients, 3593 (73.9%) were men; 4230 (87.0%) were White and 630 (13.0%) were of other races. A total of 552 patients (11.4%) had received immunotherapy. After adjusting for covariates, in the final model, White patients with HNSCC had 80% increased odds of receiving immunotherapy (adjusted odds ratio [AOR], 1.80 [95% CI, 1.30-2.48]) compared with patients of other races. There were no statistically significant differences in the odds of receiving immunotherapy based on age, sex, or smoking history. Patients with nonoropharyngeal disease were significantly more likely to receive immunotherapy than those with oropharyngeal cancer (AOR, 1.29 [95% CI, 1.05-1.59]), as were those with advanced compared with local disease (AOR, 2.39 [95% CI, 1.71-3.34]). Conclusions and Relevance: The findings of this cohort study suggest that among older patients with HNSCC, White patients may be more likely to receive immunotherapy as part of their care. Equitable access to immunotherapy and other treatment options will reduce cancer-related health disparities and improve survival of patients with HNSCC.

15.
JCO Oncol Pract ; 19(3): e397-e406, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36480772

RESUMEN

PURPOSE: While pain is prevalent among survivors of head and neck cancer (HNC), there is a lack of data on pain management in the community oncology setting. We described sociodemographic correlates and disparities associated with patient-reported pain among patients with HNC. METHODS: We used the 2017-2021 nationwide community oncology data set from Navigating Cancer, which included electronic patient-reported outcomes. We identified a retrospective cohort of patients diagnosed with HNC (N = 25,572), with ≥ 1 patient-reported pain event. We adjusted for demographic (sex, age, smoking history, marital status) and clinical (cancer site) factors associated with pain reporting and pain resolution by new pain prescription on the basis of race (White v non-White patients), using multivariate logistic regression models. RESULTS: Our analytic cohort included 2,331 patients, 90.58% White, 58.62% married, with an average age of 66.47 years. Of these, 857 patients (36.76%) reported ≥ 1 pain event during study period. Mean resolution time (in minutes) for pain incidents was significantly longer for White patients than non-White patients (99.6 ± 3.2 v 74.9 ± 7.2, P < .05). After adjusting for covariates, smoking was associated with a 25% increased odds of reporting pain incidents (adjusted odds ratio [aOR], 1.25; 95% CI, 1.03 to 1.52). There was no statistically significant difference in odds of pain reporting between White versus non-White patients (aOR, 0.97; 95% CI, 0.73 to 1.30). However, White patients were significantly more likely to receive new prescription for pain than non-White patients (aOR, 2.52; 95% CI, 1.09 to 5.86). CONCLUSION: We found racial differences in patient-reported pain management, with White patients significantly more likely to receive new pain prescriptions. As pain management is a mainstay in cancer care, equity in pain management is critical to optimize quality of life for patients with HNC.


Asunto(s)
Neoplasias de Cabeza y Cuello , Manejo del Dolor , Humanos , Anciano , Estudios Retrospectivos , Calidad de Vida , Dolor , Medición de Resultados Informados por el Paciente
16.
Carcinogenesis ; 33(6): 1149-57, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22431717

RESUMEN

Myb, a cellular progenitor of v-Myb oncogenes, is amplified in prostate cancer and exhibits greater amplification frequency in hormone-refractory disease. Here, we have investigated the functional significance of Myb in prostate cancer. Our studies demonstrate Myb expression in all prostate cancer cell lines (LNCaP, C4-2, PC3 and DU145) examined, whereas it is negligibly expressed in normal/benign prostate epithelial cells (RWPE1 and RWPE2). Notably, Myb is significantly upregulated, both at transcript (>60-fold) and protein (>15-fold) levels, in castration-resistant (C4-2) cells as compared with androgen-dependent (LNCaP) prostate cancer cells of the same genotypic lineage. Using loss and gain of function approaches, we demonstrate that Myb promotes and sustains cell cycle progression and survival under androgen-supplemented and -deprived conditions, respectively, through induction of cyclins (A1, D1 and E1), Bcl-xL and Bcl2 and downregulation of p27 and Bax. Interestingly, Myb overexpression is also associated with enhanced prostate-specific antigen expression. Furthermore, our data show a role of Myb in enhanced motility and invasion and decreased homotypic interactions of prostate cancer cells. Myb overexpression is also associated with actin reorganization leading to the formation of filopodia-like cellular protrusions. Immunoblot analyses demonstrate gain of mesenchymal and loss of epithelial markers and vice versa, in Myb-overexpressing LNCaP and -silenced C4-2 cells, respectively, indicating a role of Myb in epithelial to mesenchymal transition. Altogether, our studies provide first experimental evidence for a functional role of Myb in growth and malignant behavior of prostate cancer cells and suggest a novel mechanism for castration resistance.


Asunto(s)
Andrógenos/metabolismo , Proteínas Oncogénicas v-myb/biosíntesis , Neoplasias de la Próstata/metabolismo , Neoplasias de la Próstata/patología , Andrógenos/deficiencia , Apoptosis , Puntos de Control del Ciclo Celular/genética , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Ciclina A1/metabolismo , Ciclina D1/metabolismo , Ciclina E/metabolismo , Transición Epitelial-Mesenquimal , Humanos , Masculino , Invasividad Neoplásica , Proteínas Oncogénicas/metabolismo , Proteínas Oncogénicas v-myb/genética , Orquiectomía , Antígeno Nuclear de Célula en Proliferación/biosíntesis , Próstata/metabolismo , Próstata/patología , Antígeno Prostático Específico/biosíntesis , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/cirugía , Seudópodos , Interferencia de ARN , ARN Interferente Pequeño , Transcripción Genética , Regulación hacia Arriba , Proteína X Asociada a bcl-2/biosíntesis , Proteína Letal Asociada a bcl/metabolismo , Proteína bcl-X/metabolismo
17.
Carcinogenesis ; 32(12): 1832-9, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21983127

RESUMEN

Pancreatic cancer (PC) has the worst prognosis among all cancers due to its late diagnosis and lack of effective therapies. Therefore, identification of novel gene targets, which are differentially expressed in PC and functionally involved in malignant phenotypes, is critical to achieve early diagnosis and development of effective therapeutic strategies. We have shown previously that MUC4, an aberrantly overexpressed transmembrane mucin, promotes growth, invasion and metastasis of PC cells, thus underscoring its potential as a clinical target. Here, we report a novel microRNA (miRNA)-mediated mechanism underlying aberrant expression of MUC4 in PC. We demonstrate that the 3' untranslated region of MUC4 contains a highly conserved miRNA-150 (miR-150) binding motif and its direct interaction with miR-150 downregulates endogenous MUC4 protein levels. We also show that miR-150-mediated MUC4 downregulation is associated with a concomitant decrease in human epidermal growth factor receptor 2 and its phosphorylated form, leading to reduced activation of downstream signaling. Furthermore, our findings demonstrate that miR-150 overexpression inhibits growth, clonogenicity, migration and invasion and enhances intercellular adhesion in PC cells. Finally, our data reveal a downregulated expression of miR-150 in malignant pancreatic tissues, which is inversely associated with MUC4 protein levels. Altogether, these findings establish miR-150 as a novel regulator of MUC4 and a tumor suppressor miRNA in PC.


Asunto(s)
División Celular/fisiología , MicroARNs/fisiología , Mucina 4/metabolismo , Neoplasias Pancreáticas/patología , Regiones no Traducidas 3' , Animales , Secuencia de Bases , Western Blotting , Línea Celular Tumoral , Humanos , MicroARNs/genética , MicroARNs/metabolismo , Neoplasias Pancreáticas/metabolismo , Procesamiento Postranscripcional del ARN , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Transducción de Señal
18.
J Commun Dis ; 43(3): 177-81, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23781630

RESUMEN

Since introduction of the pertussis vaccine in 1940's the morbidity and mortality due to the infection has been markedly reduced all over the world. However the adverse effects of the inactivated whole cell pertussis vaccine like pain, swelling at the site of injection, fever, vomiting anorexia, persistent crying & drowsiness have been the cause of great concern, till date. Also the safety concerns over the use of thiomersal as an inactivating agent as well preservative have been raised in the recent past. Studies in many countries have been initiated to reduce or replace thiomersal & using other inactivating agents in the vaccines. Limited studies have been conducted in India. The present study has been undertaken as an attempt to reduce the quantity of thiomersal and modification in the procedure of production of the pertussis vaccine to reduce the toxicity, to produce better quality of whole cell pertussis vaccine. To achieve this, at the time of production of the whole cell pertussis vaccine, at Kasauli, as per the standard procedure recommended by WHO, three parallel batches of the pertussis culture were inactivated in fermenter before harvesting and thiomersal was used only one time for suspending the bacterial mass after harvesting. The resultant modified vaccine so prepared when tested showed that it was of better quality as compared to the one produced by standard procedure, when tested in mice.


Asunto(s)
Vacuna contra la Tos Ferina/efectos adversos , Humanos , Timerosal/efectos adversos
19.
Int J Food Microbiol ; 128(3): 513-5, 2009 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-19004514

RESUMEN

The genus Enterococcus like other LAB has also been featured in food and probiotic industry for decades due to its specific biochemical traits and beneficial health claims. At the same time, some enterococcal strains present an emerging pool of opportunistic pathogens for humans and are frequently armed with potential virulence factors. Thus, there is a need to assure the safety of enterococci before their use in food and probiotic preparations. Opsonophagocytic assay is an important test for the safety assessment of enterococci. In the present study comparative safety assessment of the different enterococcal strains isolated from dairy products, faeces, clinical samples and a commercial probiotic preparation was carried out by in vitro opsonophagocytic assay. Eleven strains of Enterococcus spp. were tested for their susceptibility to killing by opsonophagocytic assay. Among them, six isolates (Enterococcus faecium strain) were from our previous study (isolated from dairy products and faecal sample), four were from clinical samples and one from a probiotic preparation. Five out of six previous isolates and the isolate from probiotic preparation showed higher susceptibility to killing in contrast to the clinical isolates. The difference in the susceptibility to opsonic killing among the clinical and non-clinical Enterococcus isolates may be attributed to the presence of a capsule in the former, which protect them against the opsonophagocytic killing. Thus, these susceptible E. faecium strains may be designated as safe. However, certain other virulence traits must be evaluated prior to their exploitation in food and probiotic preparations.


Asunto(s)
Productos Lácteos/microbiología , Enterococcus/crecimiento & desarrollo , Enterococcus/inmunología , Proteínas Opsoninas/inmunología , Probióticos , Seguridad de Productos para el Consumidor , Enterococcus faecalis/crecimiento & desarrollo , Enterococcus faecalis/inmunología , Microbiología de Alimentos , Humanos , Fagocitosis , Probióticos/normas
20.
J Gastrointest Oncol ; 10(4): 695-702, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31392050

RESUMEN

BACKGROUND: Exosomes are important mediators of intercellular communications and play pivotal roles in cancer progression, metastasis and chemoresistance. CD63 and CD9 are widely accepted exosomal markers. In patients with pancreatic ductal adenocarcinoma (PDAC), positive correlation between CD9 expression and overall survival (OS) was reported. CD63 expression was conserved in all patients with no reported prognostic significance. This study explored the prognostic significance of CD63 and CD9 expression using immunohistochemistry (IHC) in patients with PDAC of mixed racial background. METHODS: Between 2012 and 2016, 49 patients with PDAC had available tissues for CD63 and CD9 staining using IHC. Two pathologists independently scored the CD63 and CD9 expression. Staining intensity was graded from 1-3 and staining percentage was estimated in 10% increments. Mean Quick-score (Q-score) (Intensity X Percentage of staining) was calculated. RESULTS: The mean Q-score for CD63 and CD9 are higher in primary tumor from the pancreas compared to pancreatic tumor from metastatic sites (185 vs. 102, P=0.0002) and (48 vs. 20, P=0.0418) respectively. We fitted Cox proportion hazard regression models to investigate the impact of the covariates CD63 and CD9 on progression free survival (PFS) and OS. CD63 has significant impact on PFS (P=0.0135) and OS (P=0.003). The higher the CD63 Q-score, the longer the PFS and OS. CD9 doesn't have significant impact on PFS (P=0.5734) or OS (P=0.2682). The mean CD63 and CD9 Q-scores are slightly higher in African American (AA) compared to Caucasians (157 vs. 149, P=0.76) and (45 vs. 29, P=0.43) respectively. CONCLUSIONS: CD63 and CD9 expression is higher in primary tumor from the pancreas compared to pancreatic tumor from metastatic sites. There is correlation between CD63 expression (but not CD9 in this cohort) and PFS and OS. To our knowledge, this is the first study to show prognostic significance of CD63 expression in patients with PDAC using IHC. A trend of higher expression of CD63 and CD9 among AA compared to Caucasians was also noticed.

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