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Adipocyte differentiation involves a series of highly synergistic processes, including clone amplification, proliferation arrest, and terminal differentiation. However, the mechanisms that control these different steps remain unclear. Emerging studies support that miRNAs play an important role in regulating adipogenesis. In this study, we found that the expression of miR-345-5p decreased during adipogenic differentiation, and overexpression of miR-345-5p reduced lipid accumulation in adipocytes and the expression of adipocyte related genes essential to lipogenic transcription, fatty acid synthesis and fatty acid transport. In addition, miR-345-5p directly targeted the 3'UTR of vascular endothelial growth factor B, and miR-345-5p mimic inhibited the expression of vascular endothelial growth factor B at both mRNA and protein levels. In conclusion, our results demonstrate that miR-345-5p inhibits adipocyte differentiation via targeting vascular endothelial growth factor B.

Hepatocellular carcinoma (HCC) is one of the most common cancers and the second leading cause of cancer related death worldwide. ZNF545 is located in the chromosome 19q13.13, which is frequent loss of heterozygosity in human astrocytoma. Methylation of ZNF545 was found frequently in a few kinds of cancers. While the function of ZNF545 in human HCC remains unclear. The purpose of this study is to explore the function and mechanism of ZNF545 in human HCC. Restoration of ZNF545 expression suppressed cell proliferation, migration and invasion, induced G1/S arrest and apoptosis in SNU449 and Huh7 cells. Further study suggested that ZNF545 suppressed HCC cell growth by inhibiting NF-kB signaling. These results were further validated by siRNA knocking down technique in ZNF545 highly expressed HXBF344 cells. In vivo, ZNF545 suppressed tumor growth in SNU449 cell xenograft mice. In conclusion, ZNF545 suppresses human HCC growth by inhibiting NF-kB signaling.

Long noncoding RNAs (lncRNAs), which are noncoding RNAs (ncRNAs) with length more than 200 nucleotides (nt), have been demonstrated to be involved in various types of cancer. Consequently, it has been frequently discussed that lncRNAs with aberrant expression in cancer serve as potential diagnostic biomarkers and therapeutic targets. However, one major challenge of developing cancer biomarkers is tumor heterogeneity which means that tumor cells show different cellular morphology, metastatic potential as well as gene expression. In this study, a custom designed microarray platform covering both mRNAs and lncRNAs was applied to tumor tissues of gastric, colon, liver and lung. 316 and 157 differentially expressed (DE-) protein coding genes and lncRNAs common to these four types of cancer were identified respectively. Besides, the functional roles of common DE-lncRNAs were inferred based on their expression and genomic position correlation with mRNAs. Moreover, mRNAs and lncRNAs with tissue specificity were also identified, suggesting their particular roles with regard to specific biogenesis and functions of different organs. Based on the large-scale survey of mRNAs and lncRNAs in four types of cancer, this study may offer new biomarkers common or specific for various types of cancer.

// Yan Dong 1, 2 , Baoping Cao 1, 3 , Meiying Zhang 1, 3 , Weidong Han 2 , James G. Herman 4 , Francois Fuks 5 , Yali Zhao 6 , Mingzhou Guo 1 1 Department of Gastroenterology & Hepatology, Chinese PLA General Hospital, Beijing 100853, China 2 Department of Molecular Biology, Institute of Basic Medicine, School of Life Sciences, Chinese PLA General Hospital, Beijing 100853, China 3 Medical College of NanKai University, Tianjin 300071, China 4 The Hillman Cancer Center, University of Pittsburgh Cancer Institute, Pittsburgh, PA 15213, U.S.A 5 Laboratory of Cancer Epigenetics, Free University of Brussels (U.L.B.), 808 route de Lennik, Brussels 1070, Belgium 6 Central Laboratory, The Affiliated Hainan Hospital of Chinese PLA General Hospital, Hai Tang Wan, Sanya 572013, China Correspondence to: Mingzhou Guo, e-mail: mzguo1@gmail.com Yali Zhao, e-mail: zhaoyl301@163.com Keywords: NKD2, DNA methylation, Wnt signaling, epigenetics, breast cancer Received: February 27, 2015 Accepted: June 08, 2015 Published: June 19, 2015 ABSTRACT Naked cuticle homolog 2 (NKD2) has been reported to antagonize Wnt signaling in zebrafish, mouse and mammals. The aim of this study is to investigate the epigenetic changes and mechanisms of NKD2 in human breast cancer development. Six breast cancer cell lines (MCF-7, ZR75–1, MDA-MB-468, MDA-MB-231, T47D and BT474) and 68 cases of primary human breast cancer were studied using methylation specific PCR, immunohistochemistry, western blot, flow cytometry techniques and a xenograft mouse model. The expression of NKD1 and NKD2 was regulated by promoter region methylation in breast cancer cells. No NKD1 methylation was found in primary human breast cancer. NKD2 was methylated in 51.4% (35/68) of human primary breast cancer samples. NKD2 methylation was significantly associated with reduction of NKD2 expression, and tumor stage ( p < 0.05). NKD2 suppressed breast cancer cell proliferation both in vitro and in vivo . NKD2 induced G1/S arrest and inhibited Wnt signaling in breast cancer cells. In conclusion, NKD2 is frequently methylated in human breast cancer, and the expression of NKD2 is regulated by promoter region methylation. NKD2 suppresses breast cancer proliferation by inhibiting Wnt signaling.

Hepatocellular carcinoma (HCC) is one of the most common malignances and the second leading cause of cancer related death worldwide. RASSF10 is located on chromosome 11p15.2, a region that shows frequent loss of heterozygosity (LOH) in several cancer types. Our previous study found that RASSF10 suppresses colorectal cancer growth by activating P53 signaling. To explore the epigenetic changes and the mechanism of RASSF10 in human HCC, 69 cases of primary HCC, twenty cases of normal liver tissue samples and 17 HCC cell lines were involved in this study. We found that RASSF10 was methylated in 82.6% (57/69) of human primary HCC and methylation of RASSF10 was significantly associated with tumor size (P < 0.05) and TNM stage (P < 0.05). The expression of RASSF10 was regulated by promoter region methylation. Restoration of RASSF10 expression suppressed cell proliferation, induced apoptosis and G2/M phase arrest, as well as sensitized cells to docetaxel and activated P53 signaling in HepG2 and QGY7703 cells. In conclusion, we demonstrated that RASSF10 is frequently methylated in human HCC and its methylation is a potential docetaxel resistant marker. Our data also indicate that RASSF10 suppresses human HCC growth by activating P53 signaling.