33 research outputs found

    miR-25 targets TNF-related apoptosis inducing ligand (TRAIL) death receptor-4 and promotes apoptosis resistance in cholangiocarcinoma.

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    It has been established that microRNA expression and function contribute to phenotypic features of malignant cells, including resistance to apoptosis. Although targets and functional roles for a number of microRNAs have been described in cholangiocarcinoma, many additional microRNAs dysregulated in this tumor have not been assigned functional roles. In this study, we identify elevated miR-25 expression in malignant cholangiocarcinoma cell lines as well as patient samples. In cultured cells, treatment with the Smoothened inhibitor, cyclopamine, reduced miR-25 expression, suggesting Hedgehog signaling stimulates miR-25 production. Functionally, miR-25 was shown to protect cells against TNF-related apoptosis-inducing ligand (TRAIL)-induced apoptosis. Correspondingly, antagonism of miR-25 in culture sensitized cells to apoptotic death. Computational analysis identified the TRAIL Death Receptor-4 (DR4) as a potential novel miR-25 target, and this prediction was confirmed by immunoblot, cell staining, and reporter assays. CONCLUSION: These data implicate elevated miR-25 levels in the control of tumor cell apoptosis in cholangiocarcinoma. The identification of the novel miR-25 target DR4 provides a mechanism by which miR-25 contributes to evasion of TRAIL-induced cholangiocarcinoma apoptosis

    A smac mimetic reduces TNF related apoptosis inducing ligand (TRAIL)-induced invasion and metastasis of cholangiocarcinoma cells.

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    UNLABELLED: Cholangiocarcinoma (CCA) cells paradoxically express tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), a death ligand that, failing to kill CCA cells, instead promotes their tumorigenicity and especially the metastatic behaviors of cell migration and invasion. Second mitochondria-derived activator of caspase (smac) mimetics are promising cancer therapeutic agents that enhance proapoptotic death receptor signaling by causing cellular degradation of inhibitor of apoptosis (IAP) proteins. Our aim was to examine the in vitro and in vivo effects of the smac mimetic JP1584 in CCA. Despite JP1584-mediated loss of cellular inhibitor of apoptosis-1 (cIAP-1) and cIAP-2, TRAIL failed to induce apoptosis in KMCH-1, TFK-1, and BDEneu CCA cells; a finding consistent with a downstream block in death signaling. Because cIAP-1 and cIAP-2 also promote nuclear factor kappa B (NF-kappaB) activation by the canonical pathway, the effect of JP1584 on this signaling pathway was examined. Treatment with JP1584 inhibited TRAIL-induced NF-kappaB activation as well as TRAIL-mediated up-regulation of the NF-kappaB target gene, matrix metalloproteinase 7 (MMP7). JP1584 also reduced TRAIL-mediated CCA cell migration and invasion in vitro. Finally, in a syngeneic rat orthotopic CCA model, JP1584 administration reduced MMP7 messenger RNA levels and extrahepatic metastases. CONCLUSION: : Although the smac mimetic JP1584 does not sensitize cells to apoptosis, it reduces TRAIL-induced CCA cell metastatic behavior. These data support the emerging concept that IAPs are prometastatic and represent targets for antimetastatic therapies

    Perception versus reality: A National Cohort Analysis of the surgery-first approach for resectable pancreatic cancer

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    INTRODUCTION: Although surgical resection is necessary, it is not sufficient for long-term survival in pancreatic ductal adenocarcinoma (PDAC). We sought to evaluate survival after up-front surgery (UFS) in anatomically resectable PDAC in the context of three critical factors: (A) margin status; (B) CA19-9; and (C) receipt of adjuvant chemotherapy. METHODS: The National Cancer Data Base (2010-2015) was reviewed for clinically resectable (stage 0/I/II) PDAC patients. Surgical margins, pre-operative CA19-9, and receipt of adjuvant chemotherapy were evaluated. Patient overall survival was stratified based on these factors and their respective combinations. Outcomes after UFS were compared to equivalently staged patients after neoadjuvant chemotherapy on an intention-to-treat (ITT) basis. RESULTS: Twelve thousand and eighty-nine patients were included (n = 9197 UFS, n = 2892 ITT neoadjuvant). In the UFS cohort, only 20.4% had all three factors (median OS = 31.2 months). Nearly 1/3rd (32.7%) of UFS patients had none or only one factor with concomitant worst survival (median OS = 14.7 months). Survival after UFS decreased with each failing factor (two factors: 23 months, one factor: 15.5 months, no factors: 7.9 months) and this persisted after adjustment. Overall survival was superior in the ITT-neoadjuvant cohort (27.9 vs. 22 months) to UFS. CONCLUSION: Despite the perceived benefit of UFS, only 1-in-5 UFS patients actually realize maximal survival when known factors highly associated with outcomes are assessed. Patients are proportionally more likely to do worst, rather than best after UFS treatment. Similarly staged patients undergoing ITT-neoadjuvant therapy achieve survival superior to the majority of UFS patients. Patients and providers should be aware of the false perception of \u27optimal\u27 survival benefit with UFS in anatomically resectable PDAC

    An Innovative Option for Venous Reconstruction After Pancreaticoduodenectomy: the Left Renal Vein

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    INTRODUCTION: Pancreatic ductal adenocarcinoma has a high mortality rate with limited treatment options. One option is pancreaticoduodenectomy, although complete resection may require venous resection. Pancreaticoduodenectomy with venous resection and reconstruction is becoming a more common practice with many choices for venous reconstruction. We describe the technique of using the left renal vein as a conduit for venous reconstruction during pancreaticoduodenectomy. METHODS: The technique for use of the left renal vein as an interposition graft for venous reconstruction during pancreaticoduodenectomy is described as well as outcomes for nine patients that have undergone the procedure. RESULTS: Nine patients, seven men, with a mean age of 57 years, have undergone the operation. There were eight interposition grafts and one patch graft. Mean operating time was 7.8 hours, and mean tumor size was 3.4 cm. Eight patients had node-positive disease, and six had involvement of the vein. Mean hospital stay was 14 days and perioperative morbidity included a superficial wound infection, delayed gastric emptying, ascites, and gastrointestinal bleeding in one patient each. Creatinine ranged from 0.8–1.1 mg/dl preoperatively and from 0.7–1.3 mg/dl at discharge. Mean follow-up was 6.8 months with normal creatinine values noted through the follow-up period. Two patients had died during follow-up from recurrent disease at 8.3 and 18.2 months after the operation. CONCLUSIONS: The left renal vein provides an additional choice for an autologous graft during pancreaticoduodenectomy with venous resection. The ease of harvesting the graft and maintenance of renal function distinguish its use

    An APRI+ALBI Based Multivariable Model as Preoperative Predictor for Posthepatectomy Liver Failure.

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    OBJECTIVE AND BACKGROUND Clinically significant posthepatectomy liver failure (PHLF B+C) remains the main cause of mortality after major hepatic resection. This study aimed to establish an APRI+ALBI, aspartate aminotransferase to platelet ratio (APRI) combined with albumin-bilirubin grade (ALBI), based multivariable model (MVM) to predict PHLF and compare its performance to indocyanine green clearance (ICG-R15 or ICG-PDR) and albumin-ICG evaluation (ALICE). METHODS 12,056 patients from the National Surgical Quality Improvement Program (NSQIP) database were used to generate a MVM to predict PHLF B+C. The model was determined using stepwise backwards elimination. Performance of the model was tested using receiver operating characteristic curve analysis and validated in an international cohort of 2,525 patients. In 620 patients, the APRI+ALBI MVM, trained in the NSQIP cohort, was compared with MVM's based on other liver function tests (ICG clearance, ALICE) by comparing the areas under the curve (AUC). RESULTS A MVM including APRI+ALBI, age, sex, tumor type and extent of resection was found to predict PHLF B+C with an AUC of 0.77, with comparable performance in the validation cohort (AUC 0.74). In direct comparison with other MVM's based on more expensive and time-consuming liver function tests (ICG clearance, ALICE), the APRI+ALBI MVM demonstrated equal predictive potential for PHLF B+C. A smartphone application for calculation of the APRI+ALBI MVM was designed. CONCLUSION Risk assessment via the APRI+ALBI MVM for PHLF B+C increases preoperative predictive accuracy and represents an universally available and cost-effective risk assessment prior to hepatectomy, facilitated by a freely available smartphone app

    Patient-Derived Xenografts Can Be Reliably Generated from Patient Clinical Biopsy Specimens

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    BACKGROUND: Patient-derived xenografts (PDX) are clinically relevant human cancer models that can be used to guide individualized medicine. We aimed to generate PDX models from clinically obtained biopsy specimens (surgical or image-guided) hypothesizing that low volume biopsy specimens could provide sufficient viable tissue to successfully engraft PDX models from patients with unresectable or metastatic disease. MATERIALS AND METHODS: We maintain a prospective high volume gastrointestinal malignancy PDX program. With informed consent and institutional approval, biopsy specimens (surgical or image-guided) were obtained from patients with unresectable or metastatic tumors: pancreatic adenocarcinoma (PDAC), cholangiocarcinoma, gastric and gallbladder carcinoma. Biopsies were implanted into immunodeficient mice. Tumor growth was monitored, viable tumor was passed into subsequent generations, and histopathology was confirmed. RESULTS: In this study, biopsy specimens from 29 patients were used for PDX engraftment. Successful PDX engraftment was variable with highest engraftment rates in gastric and gallbladder carcinoma specimens (100%) compared to engraftment rates of 33% and 29% in PDAC and cholangiocarcinoma respectively. PDX models created from metastasis biopsies compared to unresectable primary tumor tissue demonstrated higher engraftment rates (69% versus 15.4%, p = 0.001). PDX models demonstrated higher engraftment rates when biopsies were obtained during surgical operations (n = 15) compared to image-guided (n = 14) (73% versus 14%, p = 0.003). Patient age, pretreatment status, or ischemic time was not different between biopsy methods. CONCLUSIONS: PDX models can be successfully created from clinical biopsy specimens in patients with metastatic or unresectable GI cancers. The use of clinical biopsy specimens for PDX engraftment can expand the repertoire of stage-specific PDX models for downstream basic/translational research

    Thromboxane A 2

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    The role of pelvic floor dysfunction and slow colonic transit in adolescents with refractory constipation

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    Although pelvic floor dysfunction (PFD) is recognized as a cause of refractory constipation in adults, this diagnosis is not frequently considered in children and adolescents with refractory constipation. The purpose of this study was to examine the symptoms and colonic transit in adolescents with constipation evaluated for a disorder in pelvic floor function. Adolescents with refractory constipation who had undergone anorectal manometry (ARM) and balloon expulsion test (BET) were identified by retrospective review of records. Initial symptoms and the clinician's assessment were used to categorize patients by pediatric Rome II criteria, that is, functional constipation (FC), constipation-predominant irritable bowel syndrome (C-IBS) or functional fecal retention (FFR). Results of scintigraphic colonic transit studies were evaluated. A chi2 test was used to assess the association between individual clinical symptoms and Rome II criteria. Sixty-seven adolescents underwent evaluation of pelvic floor function by tests for PFD: BET was abnormal in 42%. There was no underlying disease or alternative diagnosis to account for the constipation in these patients. Among the 41 patients who also underwent scintigraphic colonic transit, 30% had slow transit constipation and 12% had both slow colonic transit and abnormal BET. Patients classified as C-IBS were more likely to report weight loss (p = 0.03), bloating (p = 0.04), and incomplete rectal evacuation (p = 0.03). Abnormal pelvic floor function and delayed colonic transit are demonstrable as single or combined problems in adolescents with refractory constipatio
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