David Velázquez-Fernández

The role of microRNA deregulation in the pathogenesis of adrenocortical carcinoma

Adrenocortical carcinoma (ACC) is an aggressive tumor showing frequent metastatic spread and poor survival. Although recent genome-wide studies of ACC have contributed to our understanding of the disease, major challenges remain for both diagnostic and prognostic assessments. The aim of this study was to identify specific microRNAs (miRNAs) associated with malignancy and survival of ACC patients. miRNA expression profiles were determined in a series of ACC, adenoma, and normal cortices using microarray. A subset of miRNAs showed distinct expression patterns in the ACC compared with adrenal cortices and adenomas. Among others, miR-483-3p, miR-483-5p, miR-210, and miR-21 were found overexpressed, while miR-195, miR-497, and miR-1974 were underexpressed in ACC. Inhibition of miR-483-3p or miR-483-5p and overexpression of miR-195 or miR-497 reduced cell proliferation in human NCI-H295R ACC cells. In addition, downregulation of miR-483-3p, but not miR-483-5p, and increased expression of miR-195 or miR-497 led to significant induction of cell death. Protein expression of p53 upregulated modulator of apoptosis (PUMA), a potential target of miR-483-3p, was significantly decreased in ACC, and inversely correlated with miR-483-3p expression. In addition, high expression of miR-503, miR-1202, and miR-1275 were found significantly associated with shorter overall survival among patients with ACC (P values: 0.006, 0.005, and 0.042 respectively). In summary, we identified additional miRNAs associated with ACC, elucidated the functional role of four miRNAs in the pathogenesis of ACC cells, demonstrated the potential involvement of the pro-apoptotic factor PUMA (a miR-483-3p target) in adrenocortical tumors, and found novel miRNAs associated with survival in ACC.

Potential additional effect of omentectomy on metabolic syndrome, acute-phase reactants, and inflammatory mediators in grade III obese patients undergoing laparoscopic Roux-en-Y gastric bypass: a randomized trial.

OBJECTIVE To assess the additional effect of sudden visceral fat reduction by omentectomy on metabolic syndrome, acute-phase reactants, and inflammatory mediators in patients with grade III obesity (G-III O) undergoing laparoscopic Roux-en-Y gastric bypass (LRYGB). RESEARCH DESIGN AND METHODS Twenty-two patients were randomized into two groups, LRYGB alone or with omentectomy. Levels of interleukin-6, C-reactive protein, tumor necrosis factor-α, leptin, adiponectin, glucose, total cholesterol, HDL cholesterol, LDL cholesterol, and triglycerides, as well as clinical characteristics, were evaluated before surgery and at 1, 3, 6, and 12 months after surgery. Results were compared between groups. RESULTS Baseline characteristics were comparable in both groups. Mean operative time was significantly higher in the group of patients who underwent omentectomy (P < 0.001). Median weight of the omentum was 795 ± 341 g. In one patient, a duodenal perforation occurred at the time of omentectomy. BMI, blood pressure, glucose, total cholesterol, LDL, and triglycerides significantly improved in both groups at 1, 3, 6, and 12 months of follow-up when compared with basal values. However, there were no consistent statistically significant differences among the groups in terms of metabolic syndrome components, acute-phase reactants, and inflammatory mediators. CONCLUSIONS Omentectomy does not have an ancillary short-term significant impact on the components of metabolic syndrome and does not induce important changes in the inflammatory mediators in patients undergoing LRYGB. Operative time is more prolonged when omentectomy is performed.

TRANSCRIPTIONAL PROFILING ENABLES MOLECULAR CLASSIFICATION OF ADRENOCORTICAL TUMOURS

OBJECTIVE Tumours in the adrenocortex are common human tumours. Malignancy is however, rare, the yearly incidence being 0.5-2 per million inhabitants, but associated with a very aggressive behaviour. Adrenocortical tumours are often associated with altered hormone production with a variety of clinical symptoms. The aggressiveness of carcinomas together with the high frequency of adenomas calls for a deeper understanding of the underlying biological mechanisms and an improvement of the diagnostic possibilities. METHODS Microarray gene expression analysis was performed in tumours of adrenocortex with emphasis on malignancy as well as hormonal activity. The sample set consisted of 17 adenomas, 11 carcinomas and 4 histological normal adrenocortexes. RNA from these was hybridised according to a reference design on microarrays harbouring 29 760 human cDNA clones. Confirmation was performed with quantitative real time-PCR and western blot analysis. RESULTS Unsupervised clustering to reveal relationships between samples based on the entire gene expression profile resulted in two subclusters; carcinomas and non-cancer specimens. A large number of genes were accordingly found to be differentially expressed comparing carcinomas to adenomas. Among these were IGF2, FGFR1 and FGFR4 in growth factor signalling the most predominant and also the USP4, UBE2C and UFD1L in the ubiquitin-proteasome pathway. Moreover, two subgroups of carcinomas were identified with different survival outcome, suggesting that survival prediction can be made on the basis of gene expression profiles. Regarding adenomas with aldosterone overproduction, OSBP and VEGFB were among the most up-regulated genes compared with the other samples. CONCLUSIONS Adrenocortical carcinomas are associated with a distinct molecular signature apparent in their gene expression profiles. Differentially expressed genes were identified associated with malignancy, survival as well as hormonal activity providing a resource of candidate genes for an exploration of possible drug targets and diagnostic and prognostic markers.

Maximal weight loss after banded and unbanded laparoscopic Roux-en-Y gastric bypass: a randomized controlled trial

BACKGROUND Laparoscopic Roux-en-Y gastric bypass (LRYGB) leads to significant weight loss and correction of co-morbidities in most patients. Banded LRYGB was designed to enhance weight loss and avoid weight regain. METHODS A randomized controlled pilot trial was designed to comparatively analyze the results and complications of banded (6.5 cm) and unbanded LRYGB. The present study was an interim analysis focused on morbidity, mortality, and maximal weight loss. RESULTS The 60 patients were divided into 2 groups. Group 1 underwent unbanded LRYGB (n = 30) and group 2 underwent banded LRYGB (n = 30). No differences were found between the 2 groups in terms of age, gender, body mass index, or operative time. No significant differences were found in the percentage of excess weight loss and body mass index at 6, 12, and 24 months between the 2 groups. The frequency of complications was similar in both groups; 1 patient required band removal because of stenosis at the level of the mesh. CONCLUSION The weight loss pattern in both groups was similar at 1 and 2 years postoperatively. Proper assessment of weight maintenance and late weight regain will require longer follow-up.

Differential RNA expression profile by cDNA microarray in sporadic primary hyperparathyroidism (pHPT): primary parathyroid hyperplasia versus adenoma.

BackgroundDifferential diagnosis between adenoma and hyperplasia in primary hyperparathyroidism (pHPT) remains a dilemma. The aim of this study was to assess differences in transcriptional genomic expression profiles between sporadic (nonfamilial) parathyroid hyperplasia (SPH), adenoma, and normal tissue.MethodsParathyroid tissue from 12 patients with parathyroid adenoma, 3 with SPH, and 2 with normal glands was selected for analysis. Histopathology was reviewed in all cases, and all patients with adenomas presented normocalcemia for a minimum of 6 months after one gland resection. Hybridizations were performed in a microarray containing 19,968 human cDNA clones including contiguous replicates. Direct comparisons were performed with reverse labeling for every different pooled sample entity. Expression levels were analyzed using the SAM, SMA, LIMMA, Cluster, and PAM packages in the R environment for statistical computing.ResultsThere were significant statistical differences between SPH and adenomas. In the direct comparison, a total of 200 genes showed differential expression (P < 0.03): 61 genes were upregulated (> 1.65-fold increase) and 139 were downregulated (> 1.58-fold decrease) with a B value > 4.68 (99.08% probability of real differential expression). When SPH was compared to normal parathyroid tissue, 50 genes were differentially expressed: 42 were upregulated (> 1.89) and 8 were downregulated (> 1.7) with a B > 4.26 (98.6% probability of real differential expression). At least 17 genes were differentially expressed and able to discriminate SPH from adenoma or normal tissue. Upregulated genes were related to apoptosis inhibition, cell proliferation, transcriptional activity and cell adhesion, among other activities. Downregulated genes were mainly related to ion channel activity, lipopolysaccharides, prostaglandin-d synthase, and integral membrane proteins.ConclusionsOur data suggest that SPH and adenoma have a singular molecular signature that, theoretically, could be used for the differential diagnosis of these entities and normal parathyroid tissue.

MicroRNA expression patterns associated with hyperfunctioning and non-hyperfunctioning phenotypes in adrenocortical adenomas

BACKGROUND The adrenocortical adenoma (ACA) entity includes aldosterone-producing adenoma (APA), cortisol-producing adenoma (CPA), and non-hyperfunctioning adenoma (NHFA) phenotypes. While gene mutations and mRNA expression profiles have been partly characterized, less is known about the alterations involving microRNA (miRNA) expression. AIM To characterize miRNA expression profile in relation to the subtypes of ACAs. SUBJECTS AND METHODS miRNA expression profiles were determined in 26 ACAs (nine APAs, ten CPAs, and seven NHFAs) and four adrenal references using microarray-based screening. Significance analysis of microarrays (SAM) was carried out to identify differentially expressed miRNAs between ACA and adrenal cortices or between tumor subtypes. Selected differentially expressed miRNAs were validated in an extended series of 43 ACAs and ten adrenal references by quantitative RT-PCR. RESULTS An hierarchical clustering revealed separate clusters for APAs and CPAs, while the NHFAs were found spread out within the APA/CPA clusters. When NHFA was excluded, the clustering analysis showed a better separation between APA and CPA. SAM analysis identified 40 over-expressed and three under-expressed miRNAs in the adenomas as compared with adrenal references. Fourteen miRNAs were common among the three ACA subtypes. Furthermore, we found specific miRNAs associated with different tumor phenotypes. CONCLUSION The results suggest that miRNA expression profiles can distinguish different subtypes of ACA, which may contribute to a deeper understanding of ACA development and potential therapeutics.

Comparative analysis between a bipolar vessel sealing and cutting device and the tie and suture technique in thyroidectomy: A randomized clinical trial

BACKGROUND Advanced bipolar and ultrasonic devices have shown significant reduction in the surgical time of thyroid operations. This randomized, controlled trial assessed if operative time and other relevant outcomes are different for thyroidectomies performed either with a second‐generation advanced bipolar device or traditional tie and suture technique. METHODS Forty‐one patients were randomized into 2 groups (advanced bipolar device and traditional tie and suture). Secondary end points included estimated blood loss, postoperative hemorrhage or hematoma requiring operative reintervention, recurrent laryngeal nerve injury, hypoparathyroidism, pain intensity, number of ligatures, analgesia usage, and loss of signal during recurrent laryngeal nerve monitoring. RESULTS Preoperative characteristics were similar between both groups. Mean operative time in the advanced bipolar device group was reduced by 32.5 minutes compared with the traditional tie and suture group (P = .006). Intraoperative blood loss was similar in both groups. Four patients presented postoperative vocal cord dysmotility, 3 in the traditional tie and suture group and 1 in the advanced bipolar device group (P = ns). Two of these 4 patients also had a >50% amplitude decrease during continuous intraoperative neuromonitoring, 1 in each group. Pain intensity, 12 hours after operation, was significantly greater in the traditional tie and suture group (P = .015), even though pain medication requirements during the initial 24 hours after operation were similar between groups (P = .97). There were no cases of postoperative hemorrhage or hematoma requiring reintervention. Postoperative, symptomatic hypocalcemia occurred in 6 patients, 4 in the traditional tie and suture, and 2 in the advanced bipolar device group. One of them developed permanent hypocalcemia. CONCLUSION The use of an advanced bipolar device in thyroid operation reduces operative time by >30 minutes, with a similar postoperative outcome profile when compared with the traditional tie and suture technique.

Assessment of two different diagnostic guidelines criteria (National Cholesterol Education Adult Treatment Panel III [ATP III] and International Diabetes Federation [IDF]) for the evaluation of metabolic syndrome remission in a longitudinal cohort of patients undergoing Roux-en-Y gastric bypass

BACKGROUND Bariatric surgery has proven to provide durable weight loss and control of comorbid conditions, including the metabolic syndrome (MS). Existing definitions of MS have caused substantial confusion regarding their concordance for identifying the same individuals. The aim of this study was to assess the value of 2 different diagnostic guidelines criteria (National Cholesterol Education Adult Treatment Panel III [ATP III] and International Diabetes Federation [IDF]) for the evaluation of remission of MS after Roux-en-Y gastric bypass (RYGB). PATIENTS AND METHODS A cohort of 381 patients who underwent a primary RYGB, satisfied the criteria for MS, and had at least o1 postoperative visit were selected. Weight loss and MS remission were analyzed 6 and 12 months after surgery by ATP III and IDF criteria. RESULTS Before surgery, 381 (48.9%) and 354 (45.4%) patients fulfilled the criteria for MS according to the ATP III and IDF, respectively. According to the ATP III definition, remission of MS after bariatric surgery occurred in 209 of 239 (87.4%) and 98/102 (96.1%) patients at 6 and 12 months, respectively. According to the IDF definition, this occurred in 180 of 232 (77.6%) and 54 of 64 (84.4%) at the same time periods. On the basis of different percentage of excess body weight loss cut-off values, the area under the curve in receiver operating characteristic analysis at 12 months was slightly better for ATP III (0.77) than IDF criteria (0.68) for remission of MS. CONCLUSIONS With the use of the IDF definition, the remission rate of MS was 10% more rigorous than with use of the ATP-III criteria. This feature is attributable to a greater discrimination of patients with high blood pressure, glycemia, and dyslipidemia. The IDF criteria seem more accurate to evaluate MS remission.

Abstract 4940: Microrna expression profiling in adrenocortical neoplasia: Implications on tumor size and functionality

Background: Tumors arising from the adrenal cortex (ACT) can be hormonally hyperfunctioning or silent. This functional phenotype, as well as their size, is of clinical importance. MicroRNAs are a class of small non-coding RNAs that negatively regulates gene expression. There is increasing evidence for their significant role in tumorigenesis. Their relevance on the functional phenotype and size of these tumors has not been previously documented. Aim: To characterize differential expression patterns of microRNAs regarding the increasing size and the functional phenotypes of ACT. Methods: Seventy frozen tissue samples were included: 16 aldosterone-producing adenomas (APA), 14 cortisol producing adenomas (CPA), 14 non-hyperfunctioning adenomas (NhFA), 19 adrenocortical carcinomas (ACC) and 7 normal adrenal cortices as controls. Global microRNA expression profiles were determined using the Agilent Human microRNA microarray, and the results were verified by quantitative real-time PCR. Results: We observed distinct microRNA expression patterns among different ACT phenotypes: majority of the APA was clustered separately from NhFA and CPA, and the ACC was independently clustered apart from all benign tumors. A larger number of miRNAs were differentially expressed between APA and CPA, while a smaller subset of differently expressed microRNAs was found between functional and non-hyperfunctional adenomas. Among the benign tumors, we found miR-21 expression was significantly correlated with increasing tumor size. Conclusion: Deregulation of microRNA expression is associated with the functional phenotype and size in ACT, and these microRNAs may have implication related to the development of adrenocortical tumors. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4940. doi:10.1158/1538-7445.AM2011-4940