Abstract. accumulating evidence has shown that micrornas (mirnas) are involved in multiple processes in cancer development and progression. upregulation of miRNA-494 (miR-494) has been identified as an oncogenic mirna and is associated with poor prognosis in several types of human cancer. However, the specific function of miR-494 in colorectal cancer remains unclear. in this study we found that the expression of mir-494 in colorectal cancer tissues and cell lines was much higher than in normal control tissues and cells, respectively. in addition, upregulation of mir-494 more frequently occurred in tissue specimens with adverse clinical stage and the presence of distant metastasis. Moreover, multivariate survival analyses demonstrated that overexpression of mir-494 is an independent prognostic factor for both progression-free and overall survival. in addition mir-494 promoted invasion and migration in colorectal cancer cells, and mir-494 directly inhibited the phosphatase and tensin homolog deleted on chromosome 10 (Pten) expression by targeting its 3'-untranslated region (3'-utr). Moreover, Pten is down regulated and inversely correlated with mir-494 expression in tissues. Thus, for the first time, we provided convincing evidence that upregulation of mir-494 was associated with tumor aggressiveness and tumor metastasis and promoted cell migration and invasion by targeting PTEN gene in colorectal cancer, and mir-494 is an independent prognostic marker for colorectal cancer patients. Introductioncolorectal carcinoma (crc) is the third most frequently diagnosed malignancy and the third leading cause of death among cancer patients in the united States (1). Despite current therapeutic strategies combining adjuvant chemotherapy, surgery and sometimes radiotherapy, the prognosis of crc remains poor, since most crc patients have distant metastases at diagnosis or develop recurrent metastatic crc following surgical treatment. although recent developments in molecular biology have provided insight into the molecular mechanisms of crc, the fundamental molecular mechanisms underlying metastasis in crc have not been fully elucidated. therefore, it is essential to identify metastasis-associated molecules as effective drug targets and to enhance the understanding of the mechanisms underlying the metastasis of crc.Micrornas (mirnas) are small non-coding rnas (~22 nucleotides in length), transcribed from non-protein-coding genes or introns, which regulate gene expression through repressing translation and cleaving their mrnas by binding to complementary sites in their 3'-untranslated region (3'-utr) (2). mirnas regulated the expression of a wide variety of target genes, and aberrant expression mirnas cause them to function as tumor suppressors or oncogenes according to the role of their target genes (3,4). Particularly, mirnas can regulate various biological processes of tumor cells, including cell proliferation, differentiation, progres sion, apoptosis, proliferation, migration and invasion (5-7). furthermore, increasing number...

Vascular endothelial cells (ECs) have a finite lifespan when cultured in vitro and eventually enter an irreversible growth arrest state called "cellular senescence." It has been shown that sphingolipids may be involved in senescence; however, the molecular links involved are poorly understood. In this study, we investigated the signaling and functions of sphingosine 1-phosphate (S1P), a serum-borne bioactive sphingolipid, in ECs of different in vitro ages. We observed that S1P-regulated responses are significantly inhibited and the S1P 1-3 receptor subtypes are markedly increased in senescent ECs. Increased expression of S1P 1 and S1P 2 was also observed in the lesion regions of atherosclerotic endothelium, where senescent ECs have been identified in vivo. S1P-induced Akt and ERK1/2 activation were comparable between ECs of different in vitro ages; however, PTEN (phosphatase and tensin homolog deleted on chromosome 10) activity was significantly elevated and Rac activation was inhibited in senescent ECs. Rac activation and senescent-associated impairments were restored in senescent ECs by the expression of dominant-negative PTEN and by knocking down S1P 2 receptors. Furthermore, the senescent-associated impairments were induced in young ECs by the expression of S1P 2 to a level similar to that of in vitro senescence. These results indicate that the impairment of function in senescent ECs in culture is mediated by an increase in S1P signaling through S1P 2 -mediated activation of the lipid phosphatase PTEN.Spingosine 1-phosphate (S1P), 2 a serum-borne bioactive lipid mediator, regulates an array of biological activities in various cell types (1-4). Most, if not all, of S1P-regulated functions are mediated by the S1P family of G-protein-coupled receptors (GPCRs) (5-7). There are five identified members of the S1P receptor family: S1P 1 , S1P 2 , S1P 3 , S1P 4 , and S1P 5 (old nomenclature: EDG-1, -5, -3, -6, and -8, respectively) (8). It was demonstrated that S1P receptor subtypes couple to different G ␣ polypeptides to regulate distinct signaling pathways (9 -11). The S1P receptor subtypes were expressed in distinct combinations in different cell types to produce an appropriate biological effect. For example, S1P 1 and S1P 3 are expressed in endothelial cells (ECs) (12). The signaling pathways regulated by the S1P 1 and S1P 3 receptors are required for the chemotaxis of endothelial cells, adherens junction assembly, endothelial morphogenesis, and angiogenic response in vitro and in vivo (7,(12)(13). However, the functional outcomes resulting from the concerted effects of the signaling pathways mediated by the distinct S1P receptor subtypes are currently unknown in a physiological environment.In contrast to S1P 1 -stimulating chemotaxis, S1P 2 -mediated signaling was shown to inhibit cell migration (14 -16). For example, embryonic fibroblasts isolated from S1P 2 null mice exhibited an enhanced chemotaxis toward S1P, serum, and platelet-derived growth factor; this enhancement was reversed by the reintroduction of S...

Conditioned medium (secretome) derived from an enriched stem cell culture stimulates chemotaxis of human fibroblasts. These cells are classified as multipotent murine mesenchymal stromal cells (mMSC) by immunochemical analysis of marker proteins. Proteomic analysis of mMSC secretome identifies nineteen secreted proteins, including extracellular matrix structural proteins, collagen processing enzymes, pigment epithelium-derived factor (PEDF) and cystatin C. Immunodepletion and reconstitution experiments show that PEDF is the predominant fibroblast chemoattractant in the conditioned medium, and immunofluorescence microscopy shows strong staining for PEDF in the cytoplasm, at the cell surface, and in intercellular space between mMSCs. This stimulatory effect of PEDF on fibroblast chemotaxis is in contrast to the PEDF-mediated inhibition of endothelial cell migration, reported previously. These differential functional effects of PEDF toward fibroblasts and endothelial cells may serve to program an ordered temporal sequence of scaffold building followed by angiogenesis during wound healing.

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AimsCancer development and progression is not only associated with the tumor cell proliferation but also depends on the interaction between tumor cells and the stromal microenvironment. A new understanding of the role of the tumor microenvironment suggests that the loss of stromal caveolin-1 (Cav-1) as a key regulator may become a potential therapy target. This study aims to elucidate whether stromal Cav-1 expression in pancreatic cancer can be a strong prognosis biomarker.MethodsTissue samples from 45 pancreatic cancer patients were studied. Parenchyma and stroma were separated and purified using laser capture microdissection. Stromal Cav-1 expression was measured from pancreatic cancer, paraneoplastic, and normal tissue using immunohistochemistry. We analyzed the correlation of stromal Cav-1 expression with clinicopathologic features and prognostic indicators, such as tumor marker HER-2/neu gene.ResultsSpecimens from six patients (13.3%) showed high levels of stromal Cav-1 staining, those from eight patients (17.8%) showed a lower, intermediate level of staining, whereas those from 31 patients (68.9%) showed an absence of staining. Cav-1 expression in cancer-associated fibroblasts was lower than that in paracancer-associated and in normal fibroblasts. Stromal Cav-1 loss was associated with TNM stage (P = 0.018), lymph node metastasis (P = 0.014), distant metastasis (P = 0.027), and HER-2/neu amplification (P = 0.007). The relationships of age, sex, histological grade, and tumor size with stromal Cav-1 expression were not significant (P>0.05). A negative correlation was found between circulating tumor cells and stromal Cav-1 expression (P<0.05).ConclusionThe loss of stromal Cav-1 in pancreatic cancer was an independent prognostic indicator, thus suggesting that stromal Cav-1 may be an effective therapeutic target for patients with pancreatic cancer.

Prenatal diagnosis of fetal congenital heart disease (CHD) has been shown to have a significant effect on prenatal and postnatal management and outcomes. However, the factors influencing the diagnostic accuracy and which pregnant trimester is the most adaptive for fetal heart disease remain uncertain despite of extensive researches. The aim of the present study was to evaluate the accuracy of echocardiography for detecting CHD and potential influence factors.We searched Chinese Biomedical Database (CBM), Medline, ISI Web of Knowledge, the Cochrane Library, and China National Knowledge Infrastructure (CNKI) to identify relevant studies from January 1, 1990 to August 13, 2015.Overall, the pooled sensitivity, specificity, diagnostic odds ratio, positive likelihood ratio, and negative likelihood ratio were 68.5% (95% confidence interval [CI], 66.8%–70.2%), 99.8% (95% CI, 99.7%–99.8%), 3026.9 (95% CI, 1417.9–6461.8), 659.41 (95% CI, 346.38–1255.3), and 0.246 (95% CI, 0.187–0.324) respectively (AUC = 0.9924). The pooled sensitivity of basic cardiac echocardiographic examination (BCEE), extended cardiac echocardiographic examination (ECEE), BCEE plus outflow tract view (BCEE + OTV), BCEE + OTV + 3VTV (BCEE plus outflow tract view plus three vessel and trachea view) for the prenatal diagnosis of CHD were 49.0%, 75.5%, 66.1%, and 83.7% respectively. The pooled sensitivity of the prenatal echocardiographic diagnosis of CHD during the first trimester, second trimester, the second to third trimester were 60.3%, 60.9%, and 77.4%, respectively. The pooled sensitivity of BCEE and ECEE for the prenatal diagnosis of CHD during the second to third trimester was significantly higher than that during the second trimester. The pooled sensitivity of the prenatal echocardiographic diagnosis of CHD for pregnancies with low risk, high risk, low and high risk, and unselected risk were 45.4%, 85.1%, 89.1%, and 66.2%, respectively. The sensitivity analysis was robust and risk level was significant source of heterogeneity. Deek test indicated no potential significant publication bias.Prenatal ultrasound is a powerful tool for the diagnosis of CHD; however, echocardiography has individual sensitivity for different gestation period, different levels of risk, and different echo-views.

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