SF3B4 as an early-stage diagnostic marker and driver of hepatocellular carcinoma

( Qingyu Shen ),( Suk Woo Nam ) 생화학분자생물학회(구 한국생화학분자생물학회) 2018 BMB Reports Vol.51 No.2

An accurate diagnostic marker for detecting early-stage hepatocellular carcinoma (eHCC) is clinically important, since early detection of HCC remarkably improves patient survival. From the integrative analysis of the transcriptome and clinicopathologic data of human multi-stage HCC tissues, we were able to identify barrier-to-autointegration factor 1 (BANF1), procollagen-lysine, 2-oxoglutarate 5-dioxygenase 3 (PLOD3) and splicing factor 3b subunit 4 (SF3B4) as early HCC biomarkers which could be detected in precancerous lesions of HCC, with superior capabilities to diagnose eHCC compared to the currently popular HCC diagnostic biomarkers: GPC3, GS, and HSP70. We then showed that SF3B4 knockdown caused G1/S cell cycle arrest by recovering p27^kip1 and simultaneously suppressing cyclins, and CDKs in liver cancer cells. Notably, we demonstrated that aberrant SF3B4 overexpression altered the progress of splicing progress of the tumor suppressor gene, kruppel like factor 4 (KLF4), and resulted in non-functional skipped exon transcripts. This contributes to liver tumorigenesis via transcriptional inactivation of p27^Kip1 and simultaneous activation of Slug genes. Our results suggest that SF3B4 indicates early-stage HCC in precancerous lesions, and also functions as an early-stage driver in the development of liver cancer. [BMB Reports: Perspective 2018; 51(2): 57-58]

Histone Deacetylases and Their Regulatory MicroRNAs in Hepatocarcinogenesis

김형석,Qingyu Shen,남석우 대한의학회 2015 Journal of Korean medical science Vol.30 No.10

A growing body of evidence suggests that epigenetic modifications are promising potential mechanisms in cancer research. Among the molecules that mediate epigenetic mechanisms, histone deacetylases (HDACs) are critical regulators of gene expression that promote formation of heterochromatin by deacetylating histone and non-histone proteins. Aberrant regulation of HDACs contributes to malignant transformation and progression in a wide variety of human cancers, including hepatocellular carcinoma (HCC), gastric cancer, lung cancer, and other cancers. Thus, the roles of HDACs have been extensively studied because of their potential as therapeutic targets. However, the underlying mechanism leading to deregulation of individual HDACs remains largely unknown. Some reports have suggested that functional microRNAs (miRNAs) modulate epigenetic effector molecules including HDACs. Here, we describe the oncogenic or tumor suppressive functions of HDAC families and their regulatory miRNAs governing HDAC expression in hepatocarcinogenesis.

Histone Deacetylases and Their Regulatory MicroRNAs in Hepatocarcinogenesis

Kim, Hyung Seok,Shen, Qingyu,Nam, Suk Woo The Korean Academy of Medical Sciences 2015 JOURNAL OF KOREAN MEDICAL SCIENCE Vol.30 No.10

T-cell immune regulator 1 enhances metastasis in hepatocellular carcinoma

양희두,은정우,이경분,Qingyu Shen,김형석,김상연,서동완,박원상,이정용,남석우 생화학분자생물학회 2018 Experimental and molecular medicine Vol.50 No.-

Recurrence and metastasis are major challenges in the management of hepatocellular carcinoma (HCC) patients after resection. To identify a metastasis-associated gene signature, we performed comparative gene expression analysis with recurrent HCC tissues from HCC patients who underwent partial or total hepatectomy and from non-metastatic primary HCC tissues. From this, we were able to identify genes associated with HCC recurrence. TCIRG1 (T-Cell Immune Regulator 1) was one of the aberrantly overexpressed genes in patients with recurrent HCC who had undergone total hepatectomy. The significant overexpression of TCIRG1 was confirmed using the Liver Hepatocellular Carcinoma dataset from The Cancer Genome Atlas. High expression of TCIRG1 was significantly associated with poor 5-year disease-free and recurrence-free survival of HCC patients. TCIRG1 knockdown suppressed tumor cell growth and proliferation in HCC cell lines; caused a significant increase in the proportion of cells in the G1/S phase of cell cycle; induced cell death; suppressed the metastatic potential of HCC cells by selectively regulating the epithelial–mesenchymal transition (EMT) regulatory proteins E-cadherin, N-cadherin, Fibronectin, Snail and Slug; and significantly attenuated the metastatic potential of ras-transformed NIH-3T3 cells in vitro and in vivo. These findings suggest that TCIRG1 functions as a metastatic enhancer by modulating growth, death and EMT in HCC cells. TCIRG1 could be a therapeutic target for the treatment of liver malignancy and metastasis.

A 300J IGBT PULSED LASER POWER SUPPLY USING ZERO-CURRENT SWITCHING HALF-BRIDGE DC-DC INVERTER

Shi Jiying,Jia Guixi,Shen Yuzhen,Xin Qirong,Wang Qingyue 전력전자학회 1995 ICPE(ISPE)논문집 Vol.1995 No.10

A 300J IGBT pulsed laser power supply designed for 4X65F high voltage pulsed xenon lamp is described. The power supply delivers an output-voltage range from 0V to 1400V to the pulsed load with maximum peak energy of 300J and maximum peak current of 600A. The efficiency range of the power supply is measured from 85.2% to 92.2%. Detailed analysis and design of the power supply, along with the experimental results are presented.

MicroRNA‐495‐3p functions as a tumor suppressor by regulating multiple epigenetic modifiers in gastric carcinogenesis

Eun, Jung Woo,Kim, Hyung Seok,Shen, Qingyu,Yang, Hee Doo,Kim, Sang Yean,Yoon, Jung Hwan,Park, Won Sang,Lee, Jung Young,Nam, Suk Woo John Wiley Sons, Ltd 2018 The Journal of pathology Vol.244 No.1

<P><B>Abstract</B></P><P>MicroRNAs (miRNAs) engage in complex interactions with the machinery that controls the transcriptome and concurrently target multiple mRNAs. Here, we demonstrate that microRNA‐495‐3p (miR‐495‐3p) functions as a potent tumor suppressor by governing ten oncogenic epigenetic modifiers (EMs) in gastric carcinogenesis. From the large cohort transcriptome datasets of gastric cancer (GC) patients available from The Cancer Genome Atlas (TCGA) and the National Center for Biotechnology Information (NCBI) Gene Expression Omnibus (GEO), we were able to recapitulate 15 EMs as significantly overexpressed in GC among the 51 EMs that were previously reported to be involved in cancer progression. Computational target prediction yielded miR‐495‐3p, which targets as many as ten of the 15 candidate oncogenic EMs. Ectopic expression of miRNA mimics in GC cells caused miR‐495‐3p to suppress ten EMs, and inhibited tumor cell growth and proliferation via caspase‐dependent and caspase‐independent cell death processing. In addition, <I>in vitro</I> metastasis assays showed that miR‐495‐3p plays a role in the metastatic behavior of GC cells by regulating SLUG, vimentin, and N‐cadherin. Furthermore, treatment of GC cells with 5‐aza‐2'‐deoxcytidine restored miR‐495‐3p expression; sequence analysis revealed hypermethylation of the miR‐495‐3p promoter region in GC cells. A negative regulatory loop is proposed, whereby DNMT1, among ten oncogenic EMs, regulates miR‐495‐3p expression via hypermethylation of the miR‐495‐3p promoter. Our findings suggest that the functional loss or suppression of miR‐495‐3p triggers overexpression of multiple oncogenic EMs, and thereby contributes to malignant transformation and growth of gastric epithelial cells. Copyright © 2017 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.</P>

Identification of aberrant overexpression of long non-coding RNA MALAT1 and role as a regulatory microRNA in liver cancer

Woo Chan Shin,Jung Woo Eun,Qingyu Shen,Hyung-Seok Kim,Hee Doo Yang,Sang Yean Kim,Young Min Ahn,박원상,이정용,Suk Woo Nam 대한독성 유전단백체 학회 2017 Molecular & cellular toxicology Vol.13 No.4

MALAT1 is deregulated in various cancers. The underlying mechanisms of MALAT1-mediated tumorigenesis are unclear. We found that MALAT1 was highly overexpressed and its overexpression was significantly associated with poor prognosis of liver cancer patients analyzed from the TCGA Liver Hepatocellular Carcinoma and Gene Expression Omnibus databases of the National Center for Biotechnology Information. Microarray analysis to identify the miRNAs deregulated by silencing MALAT1 in two liver cancer cell lines, HepG2 and Hep3B, revealed the common deregulation of 16 miRNAs including miR-574 and miR-20b in both cell lines. The predicted targets of miR-574 and miR-20b were cancer-related pathways including the RAS, MAPK and Wnt/β-catenin pathways. Aberrant expression of MALAT1 might contribute to liver cancer tumorigenesis by deregulation of cancer-associated miRNAs.

Characteristic molecular signatures of early exposure to volatile organic compounds in rat liver

Kim, Jeong Kyu,Eun, Jung Woo,Bae, Hyun Jin,Shen, Qingyu,Park, Se Jin,Kim, Hyung Seok,Park, Soha,Ahn, Young Min,Park, Won Sang,Lee, Jung Young,Nam, Suk Woo Informa UK Ltd. 2013 Biomarkers Vol.18 No.8

<P><I>Objective</I>: Investigation on whether the characteristic molecular signatures can discriminate individual volatile organic compounds (VOCs) and provide predictive markers for the detection of VOC exposure.</P><P><I>Methods</I>: Transcriptomic analysis of liver tissues was performed 48 h after the single oral administration of three VOCs doses at LD<SUB>25</SUB> or LD<SUB>5</SUB> values, to Sprague-Dawley.</P><P><I>Results</I>: Combination analysis of different multi-classifications suggested that 145 genes predicted VOC exposure. Additionally, Gene Set Enrichment Analysis of genes deregulated by VOCs revealed that T cell prolymphatic leukemia signaling was inactivated in all VOCs.</P><P><I>Conclusions</I>: These molecular markers could be widely implemented to assess and predict environmental exposure to VOCs.</P>

Targeted inactivation of HDAC2 restores p16INK4a activity and exerts antitumor effects on human gastric cancer.

Kim, Jeong Kyu,Noh, Ji Heon,Eun, Jung Woo,Jung, Kwang Hwa,Bae, Hyun Jin,Shen, Qingyu,Kim, Min Gyu,Chang, Young Gyoon,Kim, Seung-Jin,Park, Won Sang,Lee, Jung Young,Borlak, J?rgen,Nam, Suk Woo American Association for Cancer Research 2013 Molecular cancer research Vol.11 No.1

<P>Aberrant regulation of histone deacetylase 2 (HDAC2) was reported for gastric cancers. However, responsive cancer genes in disease onset and progression are less understood. HDAC2 expression was studied by quantitative RT-PCR and Western blotting. The functional consequences of HDAC2 knockdown on cell-cycle regulation, programmed cell death, and gene target identification was investigated by flow cytometry, Western blotting, electron microscopy, anchorage-independent colony formation, and cell migration assay and by whole-genome microarray. Therapeutic efficacy of HDAC2 knockdown was determined in nude mice with small hairpin expressing human gastric cancer cells. Epigenetic regulation of p16(INK4a) was studied by methylation-specific PCR and chromatin-IP to evidence HDAC2 or acetylated-histone-H4 binding at gene specific promoter sequences. HDAC2 gene and protein expression was significantly upregulated in different histopathologic grades of human gastric cancers and cancer cell lines. HDAC2 inactivation significantly reduced cell motility, cell invasion, clonal expansion, and tumor growth. HDAC2 knockdown-induced G(1)-S cell cycle arrest and restored activity of p16(INK4a) and the proapoptotic factors. This treatment caused PARP cleavage and hypophosphorylation of the Rb-protein, repressed cyclinD1, CDK4, and Bcl-2 expression and induced autophagic phenotype, that is, LC3B-II conversion. Some gastric tumors and cancer cells displayed p16(INK4a) promoter hypermethylation but treatment with 5-aza-deoxycitidine restored activity. With others the methylation status was unchanged. Here, chromatin-IP evidenced HDAC2 binding. Nonetheless, expression of p16(INK4a) was restored by HDAC2 knockdown with notable histone-H4-acetylation, as determined by chromatin-IP. Thus, p16(INK4a) is regulated by HDAC2. HDAC2 is a bona fide target for novel molecular therapies in gastric cancers. Mol Cancer Res; 11(1); 62-73. (c) 2012 AACR.</P>

Identification of a Novel Human Zinc Finger Gene, ZNF438, with Transcription Inhibition Activity

Zhong, Zhaomin,Wan, Bo,Qiu, Yun,Ni, Jun,Tang, Wenwen,Chen, Xinya,Yang, Yun,Shen, Suqin,Wang, Ying,Bai, Meirong,Lang, Qingyu,Yu, Long Korean Society for Biochemistry and Molecular Biol 2007 Journal of biochemistry and molecular biology Vol.40 No.4

There were many different families of zinc finger proteins that contained multiple cysteine and/or histidine residues and used zinc to stabilize their folds. The classical C2H2 zinc finger proteins were the founding members of this superfamily and were among the most abundant proteins in eukaryotic genomes. C2H2 proteins typically contained several C2H2 fingers that made tandem contacts along the DNA. Here we reported a novel C2H2 type zinc finger gene, ZNF438, which encoded 828 amino acids that formed five zinc finger domains. Bioinformatics analysis revealed that the ZNF438 was mapped to human chromosome 10p11.2 and shared 62% identity with rat and mouse homologues. RT-PCR analysis indicated that it was ubiquitously expressed in 18 human adult tissues. With immunofluorescence assay, it was shown that the exogenous Flag-tagged ZNF438 was located in nucleus of COS-7 cells. To further explore the function of ZNF438, we examined the transcriptional activity of ZNF438 protein by transfecting recombinant pM-ZNF438 into mammalian cells. The subsequent analysis based on the duel luciferase assay system showed that ZNF438 was a transcriptional repressor.