ABSTRACT: Solid-pseudopapillary neoplasm of pancreas (SPN), ductal adenocarcinoma (PCA), neuroendocrine tumor (NET) and non-neoplastic pancreas. comparison with gene expression of tumors and non-tumors To investigate the specific microRNA expression of SPN compared to other types of pancreatic tumor, we analyzed large-scale microRNA expressioin analysis to identify the molecular signature that may affect SPN tumorigenesis with mRNA expression profiles. Differentially expressed microRNAs were analyzed on SPNs, PCAs, NETs and Non-neoplastic tissues.
Project description:Solid-pseudopapillary neoplasm of pancreas(SPN), ductal adenocarcinoma(PCA), neuroendocrine tumor(NET) and non-neoplastic pancreas. To investigate the specific gene expression of SPN compared to other types of pancreatic tumor, we analyzed large-scale gene expressioin analysis to identify the molecular signature that may affect SPN tumorigenesis. Differentially expressed genes were analyzed on SPNs, PCAs, NETs and Non-neoplastic tissues. Solid-pseudopapillary neoplasm (SPN) is an uncommon pancreatic tumor with distinct clinicopathologic features. SPNs are characterized by mutations in exon 3 of CTNNB1. However, little is known about the gene and microRNA expression profiles of SPNs. Thus, we sought to characterize SPN-specific gene expression and identify the signaling pathways activated in these tumors. The mRNA expression profile of 14 SPNs, 6 pancreatic adenocarcinomas (PCAs), 6 pancreatic neuroendocrine tumors (NETs), and five non-neoplastic pancreatic tissues were analyzed.
Project description:Solid-pseudopapillary neoplasm of pancreas(SPN), ductal adenocarcinoma(PCA), neuroendocrine tumor(NET) and non-neoplastic pancreas. To investigate the specific gene expression of SPN compared to other types of pancreatic tumor, we analyzed large-scale gene expressioin analysis to identify the molecular signature that may affect SPN tumorigenesis. Differentially expressed genes were analyzed on SPNs, PCAs, NETs and Non-neoplastic tissues.
Project description:Solid-pseudopapillary neoplasm of pancreas (SPN), ductal adenocarcinoma (PCA), neuroendocrine tumor (NET) and non-neoplastic pancreas. comparison with gene expression of tumors and non-tumors
Project description:MicroRNAs are a family of 19- to 25-nucleotides noncoding small RNAs that primarily function as gene regulators. Aberrant microRNA expression has been described for several human malignancies, and this new class of small regulatory RNAs has both oncogenic and tumor suppressor functions. Despite this knowledge, there is little information regarding microRNAs in blood especially because microRNAs in blood, if exist, were thought to be digested by RNase. Recent studies, however, have revealed that microRNAs exist and escape digestion in serum and plasma. Thus, we performed microRNA microaray to obtain insight into microRNA deregulation in the plasma of a leukemia patient. Here, we have revealed that microRNA-638 (miR-638) is stably present in human plasmas, and miR-92a dramatically decreased in the plasmas of acute leukemia patients. Our data indicate that the ratio of miR-92a/miR-638 in plasma has strong potential for clinical application as a novel biomarker for detection of leukemia. Seven normal samples and two acute leukemia samples ware profiled and compared.
Project description:We attempt to catalog the microRNA (miRNA) expression profile according to the response of combination therapy in order to predict the outcome of drug-response before administration and clarify the relationship between aberrant expression of miRNAs and chronic liver disease. We quantified expression profile of 474 mature miRNAs by microarray in the liver biopsy specimen from 99 CH patients without history of anti-viral therapy.
Project description:Cutaneous melanoma is an increasingly common form of skin cancer. The molecular mechanisms regulating melanoma progression are not completely understood. We speculated that specific miRNAs may be involved in melanoma development. We compared the miRNA expression profiles of benign nevi and metastatic melanomas. Unsupervised hierarchical clustering demonstrated a distinct miRNA expression pattern in metastatic melanomas compared to nevi. We identified miRNAs that were differentially expressed in melanoma. Notably, miR-193b was significantly down-regulated in the melanoma tissue examined. Using functional studies we demonstrated that over-expression of miR-193b significantly reduced melanoma cell proliferation, and arrested cell at G1 phase. Further gene expression analysis revealed that miR-193b regulated targets involved in cell cycle. Cyclin D1 was down-regulated by miR-193b at both the mRNA and protein level. This is the first study to show that the miR-193b may reduce cell proliferation by directly repressing cyclin D1. Overall, our study suggests that miRNAs are dysregulated in metastatic melanoma, and that miR-193b may play an important role in melanoma. 8 benign nevi and 8 metastatic melanoma tissue samples were profiled by Agilent MicroRNA Microarray (V1.5).
Project description:Solid pseudopapillary neoplasm (SPN) of pancreas is a rare pancreatic neoplasm with a low metastatic potential. Up to 10% of patients with localized disease at presentation will develop systemic metastases, usually in the peritoneum or the liver. Due to the rarity of SPNs and the overall excellent prognosis, reliable prognostic factors to predict malignant biological behavior remain undetermined. Therefore, we aimed to define clinical, histological, and microRNA patterns that are associated with metastatic disease. We conducted a retrospective single center study on all patients operated for SPN of pancreas between 1995 and 2018. Clinical and pathological data were collected, and expression patterns of 2578 human microRNAs were analyzed using microRNA array (Affimetrix 4.1) in normal pancreases (NPs), localized tumors (LTs), and metastatic tumors (MTs). The diagnosis of SPN was confirmed in 35 patients who included 28 females and 3 males, with a mean age of 33.8 ± 13.9 years. The only clinical factor associated with metastases was tumor size (mean tumor size 5.20 ± 3.78 in LT versus 8.13± 1.03 in MT, p < 0.012). Microscopic features of malignancy were not associated with metastases, nor were immunohistochemical stains, including the proliferative index KI67. Higher expressions of miR-184, miR-10a, and miR-887, and lower expressions of miR-375, miR-217, and miR-200c were observed in metastatic tissues on microarray, and validated by real-time polymerase chain reaction. Hierarchal clustering demonstrated that the microRNA expression pattern of MTs was significantly different from that of LTs. The only clinical factor associated with metastases of SPN of pancreas was tumor size. Histological features and immunohistological staining were not predictive of metastases. A panel of six microRNAs was differentially expressed in MTs, and these findings could potentially be used to predict tumor behavior. Validation of these results is needed in larger series.
Project description:MicroRNAs (miRNAs) are small non-coding RNAs that repress gene expression at the post transcriptional level via an antisense RNA-RNA interaction. Generally, miRNAs derived from snap frozen or fresh samples are used for array based profiling. Since tissues in most pathology departments are available only in formalin fixed and paraffin embedded state, we sought to evaluate the miRNA derived from formalin fixed and paraffin embedded (FFPE) samples for microarray analysis. In this study, miRNAs extracted from matched snap frozen and FFPE samples were profiled using the Agilent miRNA array platform. Each miRNA sample was hybridized to arrays containing probes interrogating 470 human miRNAs. A total of seven cases were compared in either duplicate or triplicate. Intrachip and interchip analyses demonstrated that the processes of miRNA extraction, labeling and hybridization from both frozen and FFPE samples are highly reproducible and add little variation to the results, as technical replicates showed high correlations (Kendall tau=0.722-0.853, Spearman rank correlation coefficient=0.891-0.954). Our results showed consistent high correlation between matched frozen and FFPE samples (Kendall tau=0.669-0.815, Spearman rank correlation coefficient=0.847-0.948), supporting the use of FFPE-derived miRNAs for profiling. Keywords: formalin-fixed and paraffin-embedded (FFPE) miRNA profiling 7 matched frozen and FFPE lymphoid hyperplasia tissues were profiled and compared. Triplicate arrays were performed for two pairs of hyperplasia samples and duplicate arrays for three pairs of hyperplasia samples.
Project description:MicroRNAs (miRNAs) have important roles in gene regulation. Dysregulation of miRNAs has been associated with tumorigenesis. Recent studies suggest miR-193b is a tumor suppressor gene. In a previous study, we reported that miR-193b represses cell proliferation and regulates cyclin D1 (CCND1) in melanoma. Now we demonstrate that miR-193b regulates myeloid cell leukemia sequence 1 (Mcl-1) in melanoma cells. miRNA microarray profiling revealed the miR-193b level in malignant melanomas was significantly downregulated compared to benign nevi, while a tissue microarray demonstrated overexpression of Mcl-1 in malignant melanoma. The Mcl-1 expressions were inversely correlated with the miR-193b levels in melanoma tissue samples, suggesting a potential regulatory role of miR-193b. Overexpression of miR-193b repressed Mcl-1 in melanoma cell lines. It is well known that Mcl-1 knockdown confers cell sensitivity to ABT-737, a small molecular inhibitor of Bcl-2, Bcl-XL and Bcl-w. We found miR-193b, through repressing Mcl-1 expression, could also sensitize melanoma cells that were refractory to ABT-737. Furthermore, miR-193b directly regulates Mcl-1 by targeting the 3â untranslated region (3âUTR) of Mcl-1 mRNA. Interestingly, miR-193b may recognize sequences on the 3âUTR that do not base pair with its seed region. In conclusion, our study suggests the downregulation of miR-193b could be an early event during melanoma progression, and demonstrates miR-193b directly regulates Mcl-1 by targeting both seed and seedless sequences of the 3â UTR. 15 primary melanoma samples, 8 metastatic melanomas and 8 benign nevi samples were profiled on Agilent miRNA array platform