MiR-4443 promotes migration and invasion of breast cancer cells by inhibiting PEBP1 expression / 南方医科大学学报

OBJECTIVE@#To investigate the effect of miR-4443 expression on migration and invasion of breast cancer.@*METHODS@#We examined the expression of miR-4443 in breast carcinoma in situ and paired adjacent tissues from 3 breast cancer patients with high-throughput sequencing and verified the results using TCGA database. We also detected miR-4443 expressions using real-time quantitative PCR (RT-qPCR) in low invasive and highly invasive breast cancer cells (MCF-7 and MDA-MB-231 cells, respectively). The changes in apoptosis, migration and invasion of MCF-7 and MDA-MB-231 cells after transfection with miR-4443 mimics, mimics-NC, miR-4443 inhibitor or inhibitor-NC were analyzed using flow cytometry, wound healing assay and Transwell invasion assay. The target gene of miR-4443 was predicted by bioinformatics software and validated by a dual luciferase reporter gene system. RT-qPCR and Western blotting were performed to detect the expression of recombinant human phosphatidyl ethanolamine binding protein 1 (PEBP1) in the transfected cells.@*RESULTS@#The expression of miR-4443 was significantly higher in the breast cancer tissues than in the adjacent tissues (@*CONCLUSIONS@#MiR-4443 promotes the migration and invasion of breast cancer cells by inhibiting the expression of PEBP1, suggesting the possibility of suppressing miR-4443 expression as a potential therapeutic strategy for breast cancer.

Analysis of brain PEBP and ERK in morphine-induced CPP model in rats / 中国药理学通报

Aim To analyze the expression of phosphatidylethanolamine-binding protein(PEBP) and ERK in critical brain regions of psychological dependence rats.Methods Morphine-induced rats conditioned place preference(CPP) model was established to mimic different stages of morphine psychological dependence, during which PEBP expression and ERK activity were assayed in different brain regions.Results PEBP expression in hippocampus, prefrontal cortex, striatum and nucleus accumbens showed no change at three stages of psychological dependence.However, ERK activity increased notably in prefrontal cortex on CPP formation, and decreased remarkably in hippocampus on CPP reinstatement.Conclusions The formation and retrieval of associated memory between morphine effects and environment involve different neural circuits, in which ERK activity is critical, and PEBP might not be involved in such a memory-related ERK regulation.

Mechanism of Raf kinase inhibitor protein down-regulation in cancer / 国际肿瘤学杂志

Raf kinase inhibiting protein (RKIP)plays a vital role in various physiological processes and participates in multiple signaling pathways,with a close releationgship with tumor.The mechanism of RKIP down-regulation in neoplasms includes transcriptional regulation,methylation,acetylation,histone modifica-tion,microRNA regulation and NF-κB/Snail/RKIP loop regulation.

Anvances in research on Raf kinase inhibitory protein in common digestive system malignant tumors / 肿瘤

RKIP (Raf kinase inhibitor protein) is a member of PEBP (phosphatidylethanolamine-binding protein) family, which plays a pivotal modulatory role in MAPK (mitogen-activated protein kinase), CPCR (G-protein-coupled receptor) and NF-KB (nuclear factor-kappa B) signaling transduction pathways. In recent years, many studies reported that RKIP expression is weakened or lost in a series of malignant tumors such as prostate cancer, breast cancer and melanoma. RKIP may also play an important role in inhibition of tumor metastasis via inhibition of cell invasion and tumor angiogenesis. Recently, many experiments revealed that RKIP which is a metastasis-suppressor gene participates in the suppression of metastasis in a variety of digestive system malignant tumors and it will become a new target for prevention and control of digestive system cancer. In this article, the advances of research on RKIP in common digestive system malignant tumors were reviewed. Copyright © 2013 by TUMOR.

Relationship between raf kinase inhibitor protein and metastasis of ovarian cardnoma / 中华妇产科杂志

Objective To investigate the relationship between raf kinase inhibitor protein (SKIP), a novel metastasis suppressor gene, and metastasis of ovarian carcinoma. Methods Immunohistochemistry, RT-PCR, and western blot analysis were performed to examine the expression of SKIP in clinical samples of ovarian tumors and five human ovarian carcinoma cell lines. Stable cell lines over-expressed or deleted of SKIP were cloned to investigate the function of SKIP in ovarian cancer cells. The recombinant plasmids expressing sense (ss) or antisense (as) SKIP cDNA or empty vector was transfected into ovarian cancer cell line SKOV3 by lipofectamine. The expression level of mitogen-activated protein kinase/extracellular signal-regulated kinase kinase (MEK) and extracellular signal-regulated kinase (ERK) in ovarian cancer cells were detected by western blot analysis. Assays of cell proliferation, soft-agar colony formation, cell adhesion, and cell invasion in vitro were used to examine the malignant phenotypes of the transfected cells. Flow cytometric analysis was performed to observe the effect of SKIP on cell cycle distribution before and after transfection. Results (1 ) The expression levels of SKIP protein in ovarian carcinoma tissues from patients were found to be reduced than those in ovarian benign tumor and borderline tumor. SKOV3 clones stably expressing full-length recombinant ssRKIP, asRKIP, and their respective empty vector were obtained. (2)RKIP was able to block basal levels of MEK and ERK in ovarian cancer cells. The expression level of phosphorylation MEK in ssRKIP#1 and ssRKIP#4 cells were 0. 35, 0. 34; while the expression level of phosphorylation ERK in ssRKIP#1 and ssRKIP#4 cells were 0.48 and 0.46. (3) Abilities of cell proliferation in the ssRKIP vector-transfected cells were decreased compared with that in the non-transfected cells (P ＜0. 01 ). (4)Anchorage-independent growth in the ssRKIP#1 and ssRKIP#4 cells (83.7 ± 5.7, 106. 0±9. 2) were decreased compared with that in the empty vector-transfected cells (158.3 ± 14. 6, P＜ 0. 01). (5)Cell adhesion in the ssRKIP#1 and ssRKIP#4 cells [(68.3±0. 8)%, (64. 1±0. 9)%] were decreased compared with that in the non-transfected cells [(100. 0 ± 1.1 )%, P ＜ 0. 01]. (6) Cell invasion in the ssRKIP#1 and ssRKIP#4 cells (24 ± 5, 25±4) were decreased compared with that in the non-transfected cells (68 ± 5, P ＜ 0. 01 ). (7) ssRKIP cells had a significant increase in the G1 phase and decrease in the G2 + S phase. Conclusion RKIP could inhibits the metastasis, but also the growth of ovarian cancer cells.

Progress of the phosphatidylethanolamine binding protein / 中国药理学通报

Proteins of the phosphatidylethanolamine binding protein(PEBP) family are highly conserved throughout nature and have multiple biological functions.These small,cytosolic proteins have a typical large central sheet and a putative ligand-binding site which shares an affinity for a variety of ligands such as phospholipids,opioids,nucleotides,hydrophobic odorant molecules.PEBP plays a pivotal modulatory role in Raf-1/MEK/ERK、I?B/NF-?B、GPCR signaling cascades.As the precursor of the hippocampal cholinergic neurostimulating peptide(HCNP),PEBP may play an important role in the septal cholinergic development of the hippocampal.In addition,PEBP has the potential to contribute to neural protection,biogenesis and refinement of the membrane,Alzheimers disease(AD),opioid dependence,diabetic nephropathy,cancer and other physiological or pathophysiological processes.