BackgroundMicroRNAs are endogenous small noncoding RNAs that are functionally involved in numerous critical cellular processes including tumorigenesis. Data mining using a microRNA array database suggested that let-7d microRNA may be associated with renal cell carcinoma (RCC) malignant progression. Here, we performed further analyses to determine whether let-7d is functionally linked to RCC malignancy.MethodsQuantitative real-time PCR was used to determine the level of mature let-7d in RCC clinical specimens and its correlation with clinicopathological data. Immunohistochemical staining was conducted to characterize the stroma of RCC. Let-7d overexpressing RCC cell lines combined with mouse models bearing cell-derived xenografts and patient-derived xenografts were used to assess the functional role of let-7d in vitro and in vivo.ResultsDownregulation of let-7d in clinical RCC samples was associated with advanced tumor grade and T stage and increased vascular invasion. An inverse relationship between let-7d expression and macrophage infiltration was found in clinical RCC samples. Functional studies indicated that ectopic expression of let-7d significantly inhibited RCC cell proliferation, migration, and peripheral blood monocyte (PBMC) recruitment in vitro, as well as tumor growth, metastasis, and tumor macrophage infiltration in vivo. In silico analysis and subsequent experimental validation confirmed collagen, type III, alpha 1 (COL3A1) and C-C subfamily chemokine member CCL7 as direct let-7d target genes. The addition of COL3A1 and CCL7 counteracted the inhibitory effects of let-7d on RCC cell proliferation, migration, and PBMC recruitment. The inhibition of let-7d increased cell proliferation, migration, and PBMC recruitment by the enhanced expression of COL3A1 and CCL7 genes in vitro. The mRNA levels of COL3A1 and CCL7 were inversely correlated with let-7d level in RCC clinical specimens.ConclusionsThese results suggest that let-7d may suppress RCC growth, metastasis, and tumor macrophage infiltration at least partially through targeting COL3A1 and CCL7.Electronic supplementary materialThe online version of this article (doi:10.1186/1476-4598-13-206) contains supplementary material, which is available to authorized users.

BackgroundCompared with open oesophagectomy (OE), minimally invasive oesophagectomy (MIO) proves to have benefits in reducing the risk of pulmonary complications for patients with resectable oesophageal cancer. However, it is unknown whether MIO has superiority in reducing the occurrence of in-hospital mortality (IHM).ObjectiveThe objective of this meta-analysis was to explore the effect of MIO vs. OE on the occurrence of in-hospital mortality (IHM).Data SourcesSources such as Medline (through December 31, 2014), Embase (through December 31, 2014), Wiley Online Library (through December 31, 2014), and the Cochrane Library (through December 31, 2014) were searched.Study SelectionData of randomized and non-randomized clinical trials related to MIO versus OE were included.InterventionsEligible studies were those that reported patients who underwent MIO procedure. The control group included patients undergoing conventional OE.Study Appraisal and Synthesis MethodsFixed or random -effects models were used to calculate summary odds ratios (ORs) or relative risks (RRs) for quantification of associations. Heterogeneity among studies was evaluated by using Cochran’s Q and I2 statistics.ResultsA total of 48 studies involving 14,311 cases of resectable oesophageal cancer were included in the meta-analysis. Compared to patients undergoing OE, patients undergoing MIO had statistically reduced occurrence of IHM (OR=0.69, 95%CI =0.55 -0.86). Patients undergoing MIO also had significantly reduced incidence of pulmonary complications (PCs) (RR=0.73, 95%CI = 0.63-0.86), pulmonary embolism (PE) (OR=0.71, 95%CI= 0.51-0.99) and arrhythmia (OR=0.79, 95%CI = 0.68-0.92). Non-significant reductions were observed among the included studies in the occurrence of anastomotic leak (AL) (OR=0.93, 95%CI =0.78-1.11), or Gastric Tip Necrosis (GTN) (OR=0.89, 95%CI =0.54-1.49).LimitationMost of the included studies were non-randomized case-control studies, with a diversity of study designs, demographics of participants and surgical intervention.ConclusionsMinimally invasive oesophagectomy (MIO) has superiority over open oesophagectomy (OE) in terms of the occurrence of in-hospital mortality (IHM) and should be the first-choice surgical procedure in esophageal surgery.

The influence of high-status peers on a target individual's physical and manipulative social aggression in peer groups was examined in a diverse sample of seventh-grade students. A total of 245 individual members belonging to 65 groups were included in analyses. Aggression was assessed by peer and victim nominations in the fall and spring semesters of seventh grade. High-status peers rather than low-status peers in a group had a strong influence on individual members' physical and social aggression. High-status peers were particularly influential on low-status individual members' social aggression. A similar pattern was found for physical aggression in boys' groups.These findings imply that high-status members' aggression rather than the average of all members' may better represent the group norm. Special attention needs to be given to high-status aggressive adolescents in future intervention and prevention of aggression in schools.

Tumour ingrowth occurred more frequently in the uncovered SEMS group, while late migration was more common in the covered SEMS group.