Target prediction and verification of miR-27a in pancreatic cancer / 中华病理学杂志

<p><b>OBJECTIVE</b>To predict and verify the target gene of miR-27a in pancreatic cancer by combining the result of comparative proteome analysis.</p><p><b>METHODS</b>The bioinformatics softwares of TargetScan,PicTar and miRanda were used to predict the possible target genes of miR-27a. Based on the results of comparative proteomics analysis, possible candidates of the target genes were selected. Expression vector of target gene 3'UTR was constructed, and then target gene was verified by dual-luciferase reporter assay system. The PANC-1 and BxPC-3 pancreatic cancer cells were treated with miR-27a mimics or negative control for 48 h. Western blot analysis was used to verify alterations of protein expression of the genes.</p><p><b>RESULTS</b>PSMA1 was selected as the candidate target gene of miR-27a by bioinformatics prediction and comparative proteome analysis. Dual-luciferase reporter assay showed that miR-27a decreased luciferase activity in cells co-transfected with pmirGLO-PSMA1-WT, compared to the negative control, although significant difference of luciferase activity was not observed in cells co-transfected with pmirGLO-PSMA1-MUT between the two groups. The protein level of PSMA1 was down-regulated in pancreatic cancer cells transfected with miR-27a mimics in comparison with pancreatic cancer cells transfected with negative control.</p><p><b>CONCLUSION</b>PSMA1 is the direct target gene of miR-27a in pancreatic cancer.</p>

Construction of a miR-23a-27a cluster expression plasmid: a preliminary study of its function / 中华病理学杂志

<p><b>OBJECTIVE</b>To construct a miR-23a-27a cluster expression plasmid and to explore the target genes and function of the cluster.</p><p><b>METHODS</b>The pre-miR-23a-27a-pcDNA3.1, pre-miR-23a and pre-miR-27a plasmids were cloned by molecular biology method, and their expression efficiency was tested by dual luciferase reporter gene assay and real-time PCR. Several possible target genes of miR-23a and miR-27a were chosen using softwares and further tested by dual luciferase reporter gene assay. Finally, the function of miR-27a was analyzed in MCF-7 cell by Western blot and real-time PCR.</p><p><b>RESULTS</b>miR-23a and miR-27a were transcribed from pre-miR-23a-27a-pcDNA3.1, pre-miR-23a and pre-miR-27a plasmids in HEK293T cells, and both influenced the MRE of Sprouty2 gene in pRL-TK vector, and only miR-27a influenced the 3'-untranslated regions (UTR) full length of Sprouty2 gene while miR-27a did not influence the 3'-UTR of Sprouty2 gene with the sited-mutation in the MRE. The protein expression level of Sprouty2 gene was altered after transfection of pre-miR-27a-pcDNA3.1 plasmid while the RNA level remained unchanged.</p><p><b>CONCLUSION</b>Sprouty2 may be the functional target gene of miR-27a, and the construction of plasmids in the study may provide a fundamental basis for the further functional investigation of miR-23a and miR-27a.</p>

Effects of ezrin silencing on pancreatic cancer cell line Panc-1 / 中华病理学杂志

<p><b>OBJECTIVE</b>To explore the effects of ezrin silencing on pancreatic cancer cell line Panc-1.</p><p><b>METHODS</b>Pancreatic cancer cell line Panc-1 was transfected with ezrin silencing plasmid. The proliferation and the cell cycle status were determined by CCK-8 assay and flow cytometry analysis, respectively. Cellular membrane protrusions/microvilli formation were visualized by scanning election microscopy. Colony formation assay was used to determine the cell anchor-independent growth ability in vitro. Trans-filter migration and invasion assays were performed with 8 µm pore inserts in a 24-well BioCoat chamber with/without Matrigel.</p><p><b>RESULTS</b>Ezrin silencing decreased cellular protrusions/microvilli formation, anchorage-independent growth, cell migration and invasion, but had no effects on cell proliferation in vitro and cell cycle, in pancreatic cancer cell line Panc-1.</p><p><b>CONCLUSION</b>Ezrin expression affects the cellular protrusions/microvilli formation, anchorage-independent growth, cell migration and invasion in pancreatic cancer cell line Panc-1.</p>

Research advances in microRNA in pancreatic ductal adenocarcinoma / 中国医学科学院学报

MicroRNA (miRNA), small non-coding RNA consisted of 19-24 nucleotides, are able to regulate gene expression at the post-transcriptional level. The aberrant expressions of miRNA have been found in various cancers and contribute to carcinogenesis by promoting the expression of proto-oncogenes or by inhibiting the expression of tumor suppressor genes. miRNA are related closely with the oncogenesis, progression, and prognosis of tumors. The discovery of the aberrant expression of miRNA in pancreatic ductal adenocarcinoma (PDA) and its target genes are helpful for the understanding of the pathogenesis of PDA and for the early diagnosis and prediction of this disease. In this paper, we summarize the recent research advances in miRNA expression in PDA and its target genes and discuss the potential role of miRNA in the diagnosis, and treatment of PDA.

Significance of chemokine receptor CXCR3 expression in breast cancer / 中华病理学杂志

<p><b>OBJECTIVE</b>To investigate the expression of CXCR3 and its association with clinicopathologic features in breast carcinoma.</p><p><b>METHODS</b>The expression level of CXCR3 in 18 samples of breast cancer and corresponding normal tissues was investigated using reverse transcriptase-polymerase chain reaction (RT-PCR) and real-time RT-PCR analysis. Immunohistochemistry was carried out to examine the expression of CXCR3 in 80 breast cancers, 20 fibroadenomas and 15 normal breast tissues.</p><p><b>RESULTS</b>(1) RT-PCR and real-time RT-PCR analysis showed a higher level of CXCR3 in breast cancer tissues than that in the corresponding normal breast tissues (P < 0.05). (2) Immunohistochemistry analysis showed that the positive rate of CXCR3 in breast cancer tissues was significantly higher than that in fibroadenomas and the normal breast tissues (P < 0.05). The expression level of CXCR3 in the lymph node-positive group was higher than that in the lymph node-negative group (P < 0.05). The expression of CXCR3 was positively correlated with the number of lymph nodes involved by metastasis, tumor size and pTNM tumor stage (P < 0.05).</p><p><b>CONCLUSIONS</b>Chemokine receptor CXCR3 was up-regulated in breast cancer, and was associated with the progression of breast cancer. CXCR3 might be a novel molecular marker to predict lymph node metastasis and prognosis of breast cancer.</p>