Proteomic analysis of EZH2 downstream target proteins in hepatocellular carcinoma

MicroRNA-98 as a novel diagnostic marker and therapeutic target in cancer patients

The progress of cancer treatment methods in the last decade has significantly reduced mortality rate among these patients. Nevertheless, cancer is still recognized as one of the main causes of human deaths. One of the main reasons for the high death rate in cancer patients is the late diagnosis in the advanced tumor stages. Therefore, it is necessary to investigate the molecular biology of tumor progressions in order to introduce early diagnostic markers. MicroRNAs (miRNAs) have an important role in regulating cellular processes associated with tumor progression. Due to the high stability of miRNAs in body fluids, they are widely used as non-invasive markers in the early tumor diagnosis. Since, deregulation of miR-98 has been reported in a wide range of cancers, we investigated the molecular mechanisms of miR-98 during tumor progression. It has been reported that miR-98 mainly inhibits the tumor growth by the modulation of transcription factors and signaling pathways. Therefore, miR-98 can be introduced as a tumor marker and therapeutic target among cancer patients.

Analysis of differentially expressed proteins in lymph fluids related to lymphatic metastasis in a breast cancer rabbit model guided by contrast‑enhanced ultrasound

The aim of the present study was to identify differentially expressed proteins in the lymph fluid of rabbits with breast cancer lymphatic metastasis compared with healthy rabbits and to analyze and verify these proteins using proteomics technologies. In the process of breast cancer metastasis, the composition of the lymph fluid will also change. Rabbits with breast cancer lymph node metastasis and normal rabbits were selected for analysis. Lymph fluid was extracted under the guidance of percutaneous contrast-enhanced ultrasound. Label-free quantitative proteomics was used to detect and compare differences between the rabbit cancer model and healthy rabbits and differential protein expression results were obtained. Bioinformatics analysis was performed using Kyoto Encyclopedia of Genes and Genomes and Gene Ontology analysis software, selecting the most significantly differentially expressed proteins. Finally, parallel reaction monitoring technology was applied for validation. A total of 547 significantly differentially expressed proteins were found in the present study, which included 371 upregulated proteins and 176 downregulated proteins. The aforementioned genes were mainly involved in various cellular and metabolic pathways, including upregulated proteins, such as biliverdin reductase A and isocitrate dehydrogenase 2 and downregulated proteins, such as pyridoxal kinase. The upregulated proteins protein disulfide-isomerase 3, protein kinase cAMP-dependent type I regulatory subunit α and ATP-binding cassette sub-family C member 4 participated in immune regulation, endocrine regulation and anti-tumor drug resistance regulation, respectively. Compared with healthy rabbits, rabbits with breast cancer metastasis differentially expressed of a number of different proteins in their lymph, which participate in the pathophysiological process of tumor occurrence and metastasis. Through further research, these differential proteins can be used as predictive indicators of breast cancer metastasis and new therapeutic targets.

Acetylation stabilizes stathmin1 and promotes its activity contributing to gallbladder cancer metastasis

Gallbladder cancer is the most common biliary tract malignant tumor with highly metastatic characters and poor prognosis. However, the underlying mechanism remains unclear. Stathmin1 is ubiquitous phosphoprotein, regulating microtubule stabilization. We identified the acetylation of stahtmin1 at lysine 9 (K9) in gallbladder cancer. K9 acetylation of stathmin1 was reversely regulated by the acetyltransferase PCAF and the deacetylases sirt2. K9 acetylation of stathmin1 inhibited the combining of stathmin1 to E3 ubiquitin ligase RLIM, thereby inhibiting its ubiquitination degradation. Moreover, K9 acetylation also promoted the activity of stahtmin1 interacting and destabilizing microtubule through the inhibition of stathmin1 phosphorylation. K9 acetylated stathmin1 significantly promoted gallbladder cancer cell migration and invasion viability in vitro and lung metastasis in vivo, and indicated poor prognosis of nude mice. IHC assay suggested the positive correlation of high levels of K9 acetylation and stathmin1 expression in gallbladder cancer. Our study revealed that K9 acetylation up-regulated stathmin1 protein stability and microtubule-destabilizing activity to promoted gallbladder cancer metastasis, which provides a potential target for gallbladder cancer therapy.

Insights into the role of ERp57 in cancer

Endoplasmic reticulum resident protein 57 (ERp57) has a molecular weight of 57 kDa, belongs to the protein disulfide-isomerase (PDI) family, and is primarily located in the endoplasmic reticulum (ER). ERp57 functions in the quality control of nascent synthesized glycoproteins, participates in major histocompatibility complex (MHC) class I molecule assembly, regulates immune responses, maintains immunogenic cell death (ICD), regulates the unfolded protein response (UPR), functions as a 1,25-dihydroxy vitamin D3 (1,25(OH)2D3) receptor, regulates the NF-κB and STAT3 pathways, and participates in DNA repair processes and cytoskeletal remodeling. Recent studies have reported ERp57 overexpression in various human cancers, and altered expression and aberrant functionality of ERp57 are associated with cancer growth and progression and changes in the chemosensitivity of cancers. ERp57 may become a potential biomarker and therapeutic target to combat cancer development and chemoresistance. Here, we summarize the available knowledge of the role of ERp57 in cancer and the underlying mechanisms.

Cellular molecular and proteomic profiling deciphers the SIRT1 controlled cell death pathways in esophageal adenocarcinoma cells

Worldwide prevalence of esophageal adenocarcinomas with high rates of mortality coupled with increased mutations in esophageal cells warrants investigation to understand deregulation of cell signaling pathways leading to cancer. To this end, the current study was undertaken to unravel the cell death signatures using the model human esophageal adenocarcinoma cell line-OE33. The strategy involved targeting the key epigenetic modulator SIRT1, a histone deacetylase by a small molecule inhibitor - sirtinol. Sirtinol induced a dose-dependent inhibition of cell viability under both normoxic and hypoxic conditions with long term impact on proliferation as shown by clonogenic assays. Signature apoptotic signaling pathways including caspase activation and decreased Bcl-2 were observed. Proteomic analysis highlighted an array of entities affected including molecules involved in replication, transcription, protein synthesis, cell division control, stress-related proteins, spliceosome components, protein processing and cell detoxification/degradation systems. Importantly, the stoichiometry of the fold changes of the affected proteins per se could govern the cell death phenotype by sirtinol. Sirtinol could also potentially curb resistant and recurrent tumors that reside in hypoxic environments. Overall, in addition to unraveling the cellular, molecular and proteomics basis of SIRT1 inhibition, the findings open up avenues for designing novel strategies against esophageal adenocarcinoma.

Enhancer of Zeste Homologue 2 Inhibition Attenuates TGF-β Dependent Hepatic Stellate Cell Activation and Liver Fibrosis

BACKGROUND & AIMS

Transdifferentiation of hepatic stellate cells (HSCs) into myofibroblasts is a key event in the pathogenesis of liver fibrosis. Transforming growth factor β (TGF-β) and platelet-derived growth factor (PDGF) are canonical HSC activators after liver injury. The aim of this study was to analyze the epigenetic modulators that differentially control TGF-β and PDGF signaling pathways.

METHODS

We performed a transcriptomic comparison of HSCs treated with TGF-β or PDGF-BB using RNA sequencing. Among the targets that distinguish these 2 pathways, we focused on the histone methyltransferase class of epigenetic modulators.

RESULTS

Enhancer of zeste homolog 2 (EZH2) was expressed differentially, showing significant up-regulation in HSCs activated with TGF-β but not with PDGF-BB. Indeed, EZH2 inhibition using either a pharmacologic (GSK-503) or a genetic (small interfering RNA) approach caused a significant attenuation of TGF-β-induced fibronectin, collagen 1α1, and α-smooth muscle actin, both at messenger RNA and protein levels. Conversely, adenoviral overexpression of EZH2 in HSCs resulted in a significant stimulation of fibronectin protein and messenger RNA levels in TGF-β-treated cells. Finally, we conducted in vivo experiments with mice chronically treated with carbon tetrachloride or bile duct ligation. Administration of GSK-503 to mice receiving either carbon tetrachloride or bile duct ligation led to attenuated fibrosis as assessed by Trichrome and Sirius red stains, hydroxyproline, and α-smooth muscle actin/collagen protein assays.

CONCLUSIONS

TGF-β and PDGF share redundant and distinct transcriptomic targets, with the former predominating in HSC activation. The EZH2 histone methyltransferase is preferentially involved in the TGF-β as opposed to the PDGF signaling pathway. Inhibition of EZH2 attenuates fibrogenic gene transcription in TGF-β-treated HSCs and reduces liver fibrosis in vivo. The data discussed in this publication have been deposited in NCBI's Gene Expression Omnibus and are accessible through GEO Series accession number GSE119606 (https://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE119606).

Identification of an Anti-Inflammation Protein, Annexin A1, in Tendon Derived Stem Cells (TDSCs) of Cystic Fibrosis Mice: A Comparative Proteomic Analysis

PURPOSE

A previous study reported an elevated inflammation during tendon injury in mice with cystic fibrosis (CF), indicating the inadequate management of inflammation due to dysfunction of the cystic fibrosis transmembrane conductance regulator (CFTR). The objective of this study is to identify the targets of CFTR that contribute to the abnormal inflammation during tendon injury.

EXPERIMENTAL DESIGN

A 2D gel electrophoresis and mass-spectrometry-based comparative proteomics is performed to find the molecular targets of CFTR. And the targeted protein is further confirmed at both mRNA and protein levels.

RESULTS

It is identified that 14 proteins are differentially expressed, with annexin A1 being one of the most significantly downregulated protein. Further confirmation shows that annexin A1 is significantly decreased in TDSCs isolated from DF508 mice. As an essential anti-inflammation mediator, it is also downregulated in the injured tendon tissue of DF508 mice when compared with WT mice.

CONCLUSIONS AND CLINICAL RELEVANCE

Decreased annexin A1 expression can contribute to the elevated inflammation in DF508 mice during tendon injury. Therefore, annexin A1 can be considered as a new potential biomarker or drug target for a possible therapeutic approach in clinical practice.

Lentivirus-mediated overexpression of miR-124 suppresses growth and invasion by targeting JAG1 and EZH2 in gastric cancer

MicroRNA-124 (miR-124) expression is downregulated and has a tumor suppressor role in various types of cancer. The present study revealed that genes encoding miR-124 were frequently methylated and the expression of miR-124 was downregulated in gastric cancer tissues. Stable expression of miR-124 using a lentiviral vector inhibited gastric cancer cell growth, migration and invasion in vitro. In addition, overexpression of miR-124 suppressed gastric cancer cell xenograft growth in nude mice. The expression of the Notch ligand Jagged1 (JAG1) and enhancer of zeste homolog 2 (EZH2) was downregulated upon miR-124 overexpression, and silencing of JAG1 or EZH2 by RNA interference also suppressed gastric cancer cell growth, migration and invasion. Furthermore, expression of fibronectin and vimentin, not able elements of the epithelial-mesenchymal transition, were suppressed by overexpression of miR-124 or inhibition of JAG1 or EZH2 expressions in GC. Together, these results indicated that miR-124 suppressed gastric cancer progression, partly through inhibiting JAG1 and EZH2. Thus, lentivirus-mediated overexpression of miR-124 may be a potential therapeutic strategy against gastric cancer.

Oblongifolin M, an active compound isolated from a Chinese medical herb Garcinia oblongifolia, potently inhibits enterovirus 71 reproduction through downregulation of ERp57

There is no effective drug to treat EV71 infection yet. Traditional Chinese herbs are great resources for novel antiviral compounds. Here we showed that Oblongifolin M (OM), an active compound isolated from Garcinia oblongifolia, potently inhibited EV71 infection in a dose dependent manner. To identify its potential effectors in the host cells, we successfully identified 18 proteins from 52 differentially expressed spots by comparative proteomics studies. Further studies showed that knockdown of ERp57 inhibited viral replication through downregulating viral IRES (internal ribosome entry site) activities, whereas ectopic expression of ERp57 increased IRES activity and partly rescued the inhibitory effects of OM on viral replication. We demonstrated that OM is an effective antiviral agent; and that ERp57 is one of its cellular effectors against EV71 infection.

Targeting EZH2 in cancer

Recent genomic studies have resulted in an emerging understanding of the role of chromatin regulators in the development of cancer. EZH2, a histone methyl transferase subunit of a Polycomb repressor complex, is recurrently mutated in several forms of cancer and is highly expressed in numerous others. Notably, both gain-of-function and loss-of-function mutations occur in cancers but are associated with distinct cancer types. Here we review the spectrum of EZH2-associated mutations, discuss the mechanisms underlying EZH2 function, and synthesize a unifying perspective that the promotion of cancer arises from disruption of the role of EZH2 as a master regulator of transcription. We further discuss EZH2 inhibitors that are now showing early signs of promise in clinical trials and also additional strategies to combat roles of EZH2 in cancer.

Hotair mediates hepatocarcinogenesis through suppressing miRNA-218 expression and activating P14 and P16 signaling

BACKGROUND & AIMS

Long non-coding RNA Hotair has been considered as a pro-oncogene in multiple cancers. Although there is emerging evidence that reveals its biological function and the association with clinical prognosis, the precise mechanism remains largely elusive.

METHODS

We investigated the function and mechanism of Hotair in hepatocellular carcinoma (HCC) cell models and a xenograft mouse model. The regulatory network between miR-218 and Hotair was elucidated by RNA immunoprecipitation and luciferase reporter assays. Finally, the correlation between Hotair, miR-218 and the target gene Bmi-1 were evaluated in 52 paired HCC specimens.

RESULTS

In this study, we reported that Hotair negatively regulated miR-218 expression in HCC, which might be mediated through an EZH2-targeting-miR-218-2 promoter regulatory axis. Further investigation revealed that Hotair knockdown dramatically inhibited cell viability and induced G1-phase arrest in vitro and suppressed tumorigenicity in vivo by promoting miR-218 expression. Oncogene Bmi-1 was shown to be a functional target of miR-218, and the main downstream targets signaling, P16(Ink4a) and P14(ARF), were activated in Hotair-suppressed tumorigenesis. In primary human HCC specimens, Hotair and Bmi-1 were concordantly upregulated whereas miR-218 was downregulated in these tissues. Furthermore, Hotair was inversely associated with miR-218 expression and positively correlated with Bmi-1 expression in these clinical tissues.

CONCLUSION

Hotair silence activates P16(Ink4a) and P14(ARF) signaling by enhancing miR-218 expression and suppressing Bmi-1 expression, resulting in the suppression of tumorigenesis in HCC.

EZH2 promotes angiogenesis through inhibition of miR-1/Endothelin-1 axis in nasopharyngeal carcinoma

Emerging evidence clearly indicates that EZH2 plays a crucial role in tumor angiogenesis. However, the role of EZH2 in angiogenesis is still unknown in nasopharyngeal carcinoma (NPC). We here showed that the elevated EZH2 level was closely associated with an aggressive and poor prognostic phenotype, and was positively correlated with microvessel density (MVD) in NPC tissues. Functional studies showed that EZH2 upregulation promoted cell proliferation, migration and tubule formation of endothelial cells, and knockdown of EZH2 suppressed tumor growth, metastasis and angiogenesis in vivo. Mechanistic investigations revealed that EZH2 inhibited miR-1 transcription via promoter binding activity, leading to enhanced expression of Endothelin-1 (ET-1) which is suppressed by miR-1 targeting of ET-1 3'UTR. Furthermore, knockdown of EZH2 or overexpression of miR-1 exerted anti-angiogenic effect on NPC cells. More importantly, the neutralizing antibody against ET-1 significantly abrogated the pro-angiogenic effect of EZH2, and forced expression of ET-1 rescued the anti-angiogenic effect induced by EZH2 knockdown. In clinical specimens, ET-1 was widely overexpressed and associated with clinical stage and MVD. Taken together, our results identify a novel signaling pathway involved in NPC angiogenesis, and also suggest that EZH2-miR-1-ET-1 axis represents multiple potential therapeutic targets for NPC.

Hepatitis B virus X protein promotes hepatocellular carcinoma transformation through interleukin-6 activation of microRNA-21 expression

Hepatocellular carcinoma (HCC) is one of the most common cancers worldwide, and chronic hepatitis B virus (HBV) infection is the major risk factor of HCC. The virus encodes HBV X (HBx) protein that plays a critical role in the development of HCC. Studies have revealed numerous HBx-altered genes and signalling pathways that heavily contribute to tumourigenesis of non-tumour hepatocytes. However, the role of HBx in regulating other critical gene regulators such as microRNAs is poorly understood, which impedes the exploration of a complete HBx-associated carcinogenic network. Besides, critical microRNAs that drive the transformation of non-tumour hepatocytes are yet to be identified. Here, we overexpressed C-terminal truncated HBx protein in a non-tumour hepatocyte cell line MIHA, and measured a panel of cancer-associated miRNAs. We observed that oncogenic miR-21 was upregulated upon ectopic expression of this viral protein variant. HBx-miR-21 pathway was prevalent in HCC cells as inhibition of HBx in Hep3B and PLC/PRF/5 cells significantly suppressed miR-21 expression. Subsequently, we showed that the upregulation of miR-21 was mediated by HBx-induced interleukin-6 pathway followed by activation of STAT3 transcriptional factor. The high dependency of miR-21 expression to HBx protein suggested a unique viral oncogenic pathway that could aberrantly affect a network of gene expression. Importantly, miR-21 was essential in the HBx-induced transformation of non-tumour hepatocytes. Inhibition of miR-21 effectively attenuated anchorage-independent colony formation and subcutaneous tumour growth of MIHA cells. Our study suggested that overexpression of miR-21 was critical to promote early carcinogenesis of hepatocytes upon HBV infection.

Mass spectrometry-based serum peptide profiling in hepatocellular carcinoma with bone metastasis

AIM: To investigate the potential of serum peptides as a diagnostic tool for hepatocellular carcinoma (HCC) with bone metastasis.

METHODS: Matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF-MS) was used to characterize the serum peptide profile of HCC patients with bone metastasis. Serum samples from 138 HCC patients (66 cases with and 72 cases without bone metastasis) were randomly assigned into a training set (n = 76) and a test set (n = 62). Differential serum peptides were examined using ClinProt magnetic bead-based purification followed by MALDI-TOF-MS. The sequences of differentially expressed serum peptides were identified using liquid chromatography-mass spectrometry. A diagnostic model was established using a learning algorithm of radial basis function neural network verified by a single blind trial. Receiver operating characteristic (ROC) analysis was performed to evaluate the diagnostic power of the established model.

RESULTS: Ten peptide peaks were significantly different between HCC patients with or without bone metastasis (P < 0.001). Sequences of seven peptides with mass to charge ratios (m/z) of 1780.7, 1866.5, 2131.6, 2880.4, 1532.4, 2489.8, and 2234.3 were successfully identified. These seven peptides were derived from alpha-fetoprotein, prothrombin, serglycin, isoform 2 of inter-alpha-trypsin inhibitor heavy chain H4, isoform 1 of autophagy-related protein 16-2, and transthyretin and fibrinogen beta chains, respectively. The recognition rate and predictive power of a diagnostic model established on the basis of six significant peptides (m/z for these six peptides were 1535.4, 1780.7, 1866.5, 2131.6, 2880.4, and 2901.9) were 89.47% and 82.89%, respectively. The sensitivity and specificity of this model based upon a single blind trial were 85.29% and 85.71%, respectively. ROC analysis found that the AUC (area under the ROC curve) value was 0.911.

CONCLUSION: Our study suggested that serum peptides may serve as a diagnosis tool for HCC bone metastasis.

Intratumoral decorin gene delivery by AAV vector inhibits brain glioblastomas and prolongs survival of animals by inducing cell differentiation

Glioblastoma multiforme (GBM) is the most malignant cancer in the central nervous system with poor clinical prognosis. In this study, we investigated the therapeutic effect of an anti-cancer protein, decorin, by delivering it into a xenograft U87MG glioma tumor in the brain of nude mice through an adeno-associated viral (AAV2) gene delivery system. Decorin expression from the AAV vector in vitro inhibited cultured U87MG cell growth by induction of cell differentiation. Intracranial injection of AAV-decorin vector to the glioma-bearing nude mice in vivo significantly suppressed brain tumor growth and prolonged survival when compared to control non-treated mice bearing the same U87MG tumors. Proteomics analysis on protein expression profiles in the U87MG glioma cells after AAV-mediated decorin gene transfer revealed up- and down-regulation of important proteins. Differentially expressed proteins between control and AAV-decorin-transduced cells were identified through MALDI-TOF MS and database mining. We found that a number of important proteins that are involved in apoptosis, transcription, chemotherapy resistance, mitosis, and fatty acid metabolism have been altered as a result of decorin overexpression. These findings offer valuable insight into the mechanisms of the anti-glioblastoma effects of decorin. In addition, AAV-mediated decorin gene delivery warrants further investigation as a potential therapeutic approach for brain tumors.

Effects of EZH2 gene on the growth and migration of hepatocellular carcinoma HepG2 cells

OBJECTIVE

To investigate the effects of EZH2 gene on the growth and migration of hepatocellular carcinoma HepG2 cell in vitro and in vivo.

METHODS

EZH2 shRNA plasmid vectors were constructed and transfected into HepG2 cells. A model of EZH2 gene-silencing HepG2 cell lines was constructed, and the experimental cells were classified into 3 groups: HepG2 blank control group, HepG2-V vector control group and HepG2-EZH2 (-) group. The mRNA and protein expressions of EZH2 in these three cells were detected by real-time fluorogenic quantitative PCR and Western blotting, respectively. Cell proliferation was analyzed by MTT assay. Cells were inoculated subcutaneously in nude mice, and the growth of tumor cells in vivo was observed. Transwell chamber assay was performed to observe any change in the migration ability of cells.

RESULTS

The mRNA expression of HepG2 and HepG2-V was 100% and (95.27±10.87)%, respectively. Compared with the control group, the mRNA level of HepG2-EZH2 (-) were significantly decreased to (20.55±13.21)% (P<0.001). Similarly, the EZH2 protein expression were inhibited in HepG2-EZH2 (-) cells. The inhibition rate of tumor growth was 36.3% in vitro and 52.5% in vivo. The migration rate of the HepG2-EZH2 (-) group [(7.15±1.13)%] was significantly lower than those in the HepG2 group [(14.57±4.32)%] and the HepG2-V group [(15.21±5.22)%], with significant differences (both P<0.05).

CONCLUSIONS

EZH2 silencing can effectively inhibit the proliferation and growth of HepG2 cells in vitro and in vivo and inhibit cell migration. Therefore, the EZH2 gene may be a novel target for the treatment of liver cancer.

Role of microRNA-95 in the anticancer activity of Brucein D in hepatocellular carcinoma

Brucea javanica fruit has been used to treat amebic dysentery, malaria and various parasites and it has been applied as an anti-cancer agent in Traditional Chinese Medicine. Brucein D (BD) is a naturally occurring compound extracted from Brucea javanica fruit which shows anti-cancer activity against pancreatic cancer. Here, we further demonstrated that BD inhibited hepatocellular carcinoma (HCC) cell growth in vitro and tumor growth in vivo that were attributed to the induction of cell apoptosis. BD did not exert growth inhibition on non-tumorigenic human hepatocytes. MTT assay was used to measure cell viability. Annexin V and TUNEL assay were applied to identify apoptotic cells in cell suspension and in tissue section respectively. Downstream micro-RNA (miRNA) targets of BD were screened out by miRNA array. miRNAs and their target proteins were identified by bioinformatics analysis and luciferase reporter assay. 39 miRNAs regulated by BD in HCC were identified. miR-95 was found to be a potential drug target of BD. We further identified CUG triplet repeat RNA-binding protein 2 (CUGBP2) as the downstream target of miR-95. Our data suggested that BD exerted its anti-cancer activity against HCC through modulation of miR-95 expression.

A potential antitumor ellagitannin, davidiin, inhibited hepatocellular tumor growth by targeting EZH2

Hepatocellular carcinoma (HCC) is the fifth most common cancer worldwide and is the third most common cause of cancer-related deaths. Currently available treatment options for HCC patients are scarce resulting in an urgent need to develop a novel effective cure. Polygonum capitatum is a medicinal herb which has been used to treat inflammatory diseases in Miao nationality of China. We recently isolated a pure compound davidiin from P. capitatum extract. Four HCC cell lines were treated with davidiin. Cell viability was recorded by MTT assay. siRNAs targeting enhancer of zeste homolog 2 (EZH2) were applied to modulate the expression of EZH2. Established xenograft mice models of HCC were applied to evaluate the in vivo anticancer activity of davidiin. We investigated the anticancer activity and the underlying mechanism of davidiin. The compound inhibited HCC cell growth and also suppressed tumor growth in xenografted HCC mouse. Such inhibition was facilitated by specifically downregulation on EZH2. The compound possesses anticancer activity both in vitro and in vivo which warrants further clinical investigation as a potential anti-HCC agent.

Differential protein analysis of lymphocytes between children with acute lymphoblastic leukemia and healthy children

We identified differential proteins in lymphocytes between patients with childhood acute lymphoblastic leukemia (c-ALL) and healthy children. Samples of bone marrow lymphocytes from children with c-ALL and peripheral blood lymphocytes from healthy children were collected, and total proteins were extracted and separated from these samples followed by two-dimensional gel electrophoresis for comparative analysis. The differential protein spots in c-ALL cells were digested in situ, and then analyzed with matrix-assisted laser desorption ionization/time of flight mass spectrometry (MALDI-TOF-MS) followed by identification using the relevant database. Fifteen differential expression proteins were obtained by comparative proteomics analysis. Of the 15 differential proteins, eight were identified. Of the eight proteins, two had high expression and six low expression in c-ALL cells. The eight differential proteins are expected to become new diagnostic markers and drug targets for c-ALL.

Enhancer of zeste homolog 2 silences microRNA-218 in human pancreatic ductal adenocarcinoma cells by inducing formation of heterochromatin

BACKGROUND & AIMS

Enhancer of zeste homolog 2 (EZH2) is a histone methyltransferase that is overexpressed by pancreatic ductal adenocarcinoma (PDAC) cells and increases their aggressiveness. We identified microRNAs (miRs) that are regulated by EZH2 and studied their functions in PDAC cells.

METHODS

We performed miR profile analysis of PDAC cells incubated with EZH2 inhibitor 3-deazaneplanocin A, and pancreatic ductal epithelial cells that overexpressed EZH2. Expression levels of miRs and the targets of miRs were analyzed by quantitative reverse transcription polymerase chain reaction and immunohistochemistry. We expressed different forms of EZH2 to analyze functional domains and used small interfering RNAs to reduce its level in PDAC cells.

RESULTS

Expression of miR-218 was repressed by EZH2 in PDAC cells. Levels of miR-218 were significantly reduced in primary PDAC tumor samples compared with paired, adjacent nontumor tissue. Overexpression of miR-218 in SW1990 cells reduced their proliferation and tumor formation and metastasis in nude mice. Loss of miR-218 from SW1990 cells increased levels of UDP-glycosyltransferase 8 and miR-218 was found to bind to its 3'-UTR. Levels of UDP-glycosyltransferase protein and messenger RNA were associated with the metastatic potential of PDAC cell lines and progression of tumors in patients. EZH2 was found to silence miR-218 by binding to its promoter, promoting heterochromatin formation, and recruiting the DNAs methyltransferase 1, 3A, and 3B.

CONCLUSIONS

EZH2 is up-regulated in PDAC samples from patients and silences miR-218. MicroRNA-218 prevents proliferation of PDAC cells in culture, and tumor growth and metastasis in nude mice. MicroRNA-218 reduces levels of UDP-glycosyltransferase, which is associated with the metastatic potential of PDAC tumors in mice and progression of human PDAC.

Sorafenib suppresses growth and survival of hepatoma cells by accelerating degradation of enhancer of zeste homolog 2

Enhancer of zeste homolog 2 (EZH2) is a mammalian histone methyltransferase that contributes to the epigenetic silencing of target genes that regulate cancer cell growth and survival. It is overexpressed in hepatocellular carcinoma (HCC) with a clinical significance that remains obscure. Sorafenib, a multikinase inhibitor, has been used as a first-line therapeutic drug and shown clinical efficiency for advanced-stage HCC patients. In the present study, we found that sorafenib lowered the protein level of EZH2 through accelerating proteasome-mediated EZH2 degradation in hepatoma cells. Overexpression of EZH2 reversed sorafenib-induced cell growth arrest, cell cycle arrest, and cell apoptosis dependent on histone methyltransferase activity in hepatoma cells. More importantly, shRNA-mediated EZH2 knockdown or EZH2 inhibition with 3-deazaneplanocin A treatment promoted sorafenib-induced hepatoma cell growth arrest and apoptosis. Sorafenib altered the hepatoma epigenome by reducing EZH2 and H3K27 trimethylation. These results revealed a novel therapeutic mechanism underlying sorafenib treatment in suppressing hepatoma growth and survival by accelerating EZH2 degradation. Genetic deletion or pharmacological ablation of EZH2 made hepatoma cells more sensitive to sorafenib, which helps provide a strong framework for exploring innovative combined therapies for advanced-stage HCC patients.

Separation technique for the determination of highly polar metabolites in biological samples

Metabolomics is a new approach that is based on the systematic study of the full complement of metabolites in a biological sample. Metabolomics has the potential to fundamentally change clinical chemistry and, by extension, the fields of nutrition, toxicology, and medicine. However, it can be difficult to separate highly polar compounds. Mass spectrometry (MS), in combination with capillary electrophoresis (CE), gas chromatography (GC), or high performance liquid chromatography (HPLC) is the key analytical technique on which emerging "omics" technologies, namely, proteomics, metabolomics, and lipidomics, are based. In this review, we introduce various methods for the separation of highly polar metabolites.

MicroRNA-98 and microRNA-214 post-transcriptionally regulate enhancer of zeste homolog 2 and inhibit migration and invasion in human esophageal squamous cell carcinoma

Background

The enhancer of zeste homolog 2 (EZH2) was found to be overexpressed and associated with tumor metastasis in esophageal squamous cell carcinoma (ESCC). On the other hand, it was reported that miR-26a, miR-98, miR-101, miR-124, miR-138 and miR-214 could inhibit the expression of EZH2 in some tumors. However, the role of miRNAs in the regulation of EZH2 expression in human ESCC has not been documented. The aim of this study was to determine the role of these miRNAs in the regulation of tumor metastasis via EZH2 overexpression in human ESCC.

Methods and results

The expression of these miRNAs and EZH2 mRNA were examined by qPCR and the expression of EZH2 protein was detected by western blot. The role of these miRNAs in migration and invasion was studied in ESCC cell line (Eca109) transfected with miRNA mimics or cotransfected with miRNA mimics and pcDNA-EZH2 plasmid (without the 3’-UTR of EZH2). Through clinical investigation, we found that miR-98 and miR-214 expression was significantly lower in ESCC tissues than in matched normal tissues, and the expression level of miR-98 and miR-214 was inversely correlated to EZH2 protein expression and the clinical features such as pathological grade, tumor stage and lymph node metastasis in ESCC. In Eca109 cells, overexpression of miR-98 and miR-214 significantly inhibited the migration and invasion of ESCC cells, which was reversed by transfection of EZH2.

Conclusions

These findings suggest that decreased expression of miR-98 and miR-214 might promote metastasis of human ESCC by inducing accumulation of EZH2 protein.

Progress in understanding the role of EZH2 in the pathogenesis of hepatocellular carcinoma

Primary hepatocellular carcinoma (HCC) is one of the most common malignancies, with a multifaceted molecular pathogenesis. The activation of proto-oncogenes and the inactivation of tumor suppressor genes induced by genetic and epigenetic alterations are major mechanisms of hepatocarcinogenesis. The Polycomb-group gene EZH2 is a newly identified oncogene with gene silencing function, which is mediated by intrinsic histone methyltransferase activity for trimethylation of histone h3 lysine 27 (H3K27me3) and involved in regulation of X-inactivation, cell differentiation and embryonic development. In recent years, EZH2 has been reported to be highly expressed in HCC and is closely related to hepatocarcinogenesis by aberrant regulation of tumor-associated gene expression. In this paper we give an overview of the role of EZH2 in the development of HCC.

Microinjection manipulation resulted in the increased apoptosis of spermatocytes in testes from intracytoplasmic sperm injection (ICSI) derived mice

The invention of intracytoplasmic sperm injection (ICSI) has possibly been the most important development in reproductive medicine, one that has given hope to thousands of infertile couples worldwide. However, concerns remain regarding the safety of this method since it is a more invasive procedure than in vitro fertilization (IVF), since a spermatozoon is injected into the oocyte cytoplasm. Using mice derived from IVF technology as a control, we assessed the influence of invasive microinjection in the process of transferring sperm into oocyte cytoplasm in ICSI procedure on the development and physiologic function of resultant offspring. Our results demonstrated that mice produced from ICSI and IVF had no significant difference in phenotypic indices including body weight, forelimb physiology, and learning and memory ability. However, increased spermatocyte apoptosis was observed in the testis of adult ICSI mice, when compared with IVF mice. And, decreased testis weight and marked damage of spermatogenic epithelia were found in aged ICSI mice. Furthermore, proteomic analysis verified that most of the differentiated proteins in testes between adult ICSI and IVF mice were those involved in regulation of apoptosis pathways. Our results demonstrated that the microinjection manipulation used in the ICSI procedure might pose potential risks to the fertility of male offspring. The changed expression of a series of proteins relating to apoptosis or proliferation might contribute to it. Further studies are necessary to better understand all the risks of ICSI.

Lentivirus-mediated RNA interference targeting Bax inhibitor-1 suppresses ex vivo cell proliferation and in vivo tumor growth of nasopharyngeal carcinoma

Bax inhibitor-1 (Bi-1), an anti-apoptotic protein that belongs to the Bcl-2 family, plays an important role in the mitochondrial apoptosis pathway to suppress Bax-induced apoptosis. In several human cancers, including nasopharyngeal carcinoma, its expression was found to be increased; however, up-regulated expression of this protein has been linked to increased cell proliferations. In this study, we down-regulated the gene expression of Bi-1 in nasopharyngeal carcinoma cells by using a lentivirus transfection system packed with short hairpin RNA targeting Bi-1 and used an in vivo model to assess its efficacy as a target in human gene therapy. The data indicated that human malignant nasopharyngeal carcinoma cells, CNE-1 and SUNE-1, transfected with lentiviral short hairpin RNA targeting Bi-1 grew more slowly and showed a higher degree of apoptosis. Moreover, the tumorigenicity of CNE-1 was significantly suppressed when inoculated mice were intratumorically injected with the same vector. Taken together, these data lead us to conclude that Bi-1 plays a crucial role in CNE-1 tumorigenesis and that Bi-1 may be a novel therapeutic target for nasopharyngeal carcinoma.

EZH2-mediated concordant repression of Wnt antagonists promotes β-catenin-dependent hepatocarcinogenesis

Enhancer of zeste homolog 2 (EZH2) is the catalytic subunit of the Polycomb-repressive complex 2 (PRC2) that represses gene transcription through histone H3 lysine 27 trimethylation (H3K27me3). Although EZH2 is abundantly present in various cancers, the molecular consequences leading to oncogenesis remain unclear. Here, we show that EZH2 concordantly silences the Wnt pathway antagonists operating at several subcellular compartments, which in turn activate Wnt/β-catenin signaling in hepatocellular carcinomas (HCC). Chromatin immunoprecipitation promoter array and gene expression analyses in HCCs revealed EZH2 occupancy and reduced expression of Wnt antagonists, including the growth-suppressive AXIN2, NKD1, PPP2R2B, PRICKLE1, and SFRP5. Knockdown of EZH2 reduced the promoter occupancy of PRC2, histone deacetylase 1 (HDAC1), and H3K27me3, whereas the activating histone marks were increased, leading to the transcriptional upregulation of the Wnt antagonists. Combinatorial EZH2 and HDAC inhibition dramatically reduced the levels of nuclear β-catenin, T-cell factor-dependent transcriptional activity, and downstream pro-proliferative targets CCND1 and EGFR. Functional analysis revealed that downregulation of EZH2 reduced HCC cell growth, partially through the inhibition of β-catenin signaling. Conversely, ectopic overexpression of EZH2 in immortalized hepatocytes activated Wnt/β-catenin signaling to promote cellular proliferation. In human HCCs, concomitant overexpression of EZH2 and β-catenin was observed in one-third (61/179) of cases and significantly correlated with tumor progression. Our data indicate that EZH2-mediated epigenetic silencing contributes to constitutive activation of Wnt/β-catenin signaling and consequential proliferation of HCC cells, thus representing a novel therapeutic target for this highly malignant tumor.

Overexpression of Bax inhibitor-1 (BI-1) induces cell transformation in NIH3T3 cells

BI-1 (Bax inhibitor-1), an apoptosis-inhibiting gene belonging to the Bcl-2 protein family, plays an important role in mitochondrial apoptosis pathway to suppress Bax-induced apoptosis. To investigate the potential role of BI-1 in promoting cell growth and tumorigenesis, in the present study we overexpressed the BI-1 gene in NIH3T3 cells using the lentivirus-mediated gene expression system. Our in vitro studies showed that NIH3T3 cells overexpressing BI-1 displayed a significantly higher growth rate and formed more and larger colonies than the control cells. In addition, our in vivo studies indicated that the lenti-BI-1-infected cells formed obvious tumours, while no tumours were formed by the control cells after subcutaneously injected into nude mice. These results strongly suggested that the BI-1 gene might play a crucial role in neoplastic genesis and development.

MiR-26a inhibits cell growth and tumorigenesis of nasopharyngeal carcinoma through repression of EZH2

Several microRNAs (miRNA) have been implicated in nasopharyngeal carcinoma (NPC), a highly invasive and metastatic cancer that is widely prevalent in southern China. In this study, we report that microRNA miR-26a is commonly downregulated in NPC specimens and NPC cell lines with important functional consequences. Ectopic expression of miR-26a dramatically suppressed cell proliferation and colony formation by inducing G(1)-phase cell-cycle arrest. We found that miR-26a strongly reduced the expression of EZH2 oncogene in NPC cells. Similar to the restoring miR-26 expression, EZH2 downregulation inhibited cell growth and cell-cycle progression, whereas EZH2 overexpression rescued the suppressive effect of miR-26a. Mechanistic investigations revealed that miR-26a suppressed the expression of c-myc, the cyclin D3 and E2, and the cyclin-dependent kinase CDK4 and CDK6 while enhancing the expression of CDK inhibitors p14(ARF) and p21(CIP1) in an EZH2-dependent manner. Interestingly, cyclin D2 was regulated by miR-26a but not by EZH2, revealing cyclin D2 as another direct yet mechanistically distinct target of miR-26a. In clinical specimens, EZH2 was widely overexpressed and its mRNA levels were inversely correlated with miR-26a expression. Taken together, our results indicate that miR-26a functions as a growth-suppressive miRNA in NPC, and that its suppressive effects are mediated chiefly by repressing EZH2 expression.

Proteomic identification of microRNA-122a target proteins in hepatocellular carcinoma

MicroRNA-122a (miR-122a) is a liver-specific miRNA that is frequently downregulated in hepatocellular carcinoma (HCC). The exact functional role of miR-122a and its target in HCC remain largely unknown. We developed a lentiviral vector for the expression of pre-miR-122a (Lenti-miR-122a). Lenti-miR-122a inhibited HCC cell growth and induced apoptosis in vitro. We employed proteomic profiling to identify the target proteins of miR-122a. In total, ten proteins with differential expression in HCC cells infected with Lenti-miR-122a were identified. Amongst them, downregulation of peroxiredoxin 2 (PRDXII) by miR-122a was validated by Western blotting. Using bioinformatics analysis, predictable target sites of miR-122a were identified in the 5'-UTR of PRDXII mRNA. Luciferase reporter assay confirmed the regulation of miR-122a on 5'-UTR of PRDXII. In conclusion, PRDXII was identified to be the new target of miR-122a.

Comparative serum proteomic analysis of patients with acute-on-chronic liver failure: alpha-1-acid glycoprotein maybe a candidate marker for prognosis of hepatitis B virus infection

The acute-on-chronic liver failure (AoCLF) caused by hepatitis B virus (HBV) infection remains to be a challenge in clinics with a high mortality rate in China, and it is important to identify biomarkers to foresee the prognosis of patients with HBV. The current study analysed serum proteome changes of acute-on-chronic liver failure as a result of acute exacerbation of chronic hepatitis B infection. Serum samples were collected from normal subjects (NS, n = 8), patients with chronic hepatitis B (CHB, n = 12) and patients with AoCLF (n = 12). After removal of albumin/IgG and ultramembrane centrifugation, serum proteins were separated by two-dimensional gel electrophoresis. Differentially expressed spots were identified by matrix-associated laser desorption ionization time-of-flight tandem mass spectrometry. Through the removal of albumin/IgG and ultramembrane centrifugation, the well-resolved and reproducible two-dimensional gel electrophoresis (2-DE) profiles were obtained. A total of 23 proteins were identified on 2-DE profiles by their differential expression between the three cohorts. Mass spectrometry analysis resulted in the identification of 12 proteins unambiguously. Western blot analysis confirmed the proteomics results that the α1-acid glycoprotein (α1-AGP) levels decrease significantly in plasma of patients with AoCLF, but somewhat decreased in patients with chronic HBV. Further α1-AGP levels in bulk serum samples were measured by immune turbidimetry including normal subjects group (n = 25), acute hepatitis group (n = 36), chronic hepatitis group (n = 52) and AoCLF group (n = 48), the level of α1-AGP in AoCLF groups sharply decrease than other groups. Our study shows that α1-AGP may be a potential plasma biomarker for AoCLF diagnosis because of acute exacerbation of chronic hepatitis B infection.

RNAi targeting EZH2 inhibits tumor growth and liver metastasis of pancreatic cancer in vivo

The function of EZH2 in tumorigenesis and liver metastasis of pancreatic cancer has never been elucidated in vivo. EZH2 was overexpressed in pancreatic carcinomas and its overexpression was associated with tumor differentiation and pT status. Suppression of EZH2 caused a significant growth inhibition of pancreatic cancer cells in vitro and markedly diminished their tumorigenicity in vivo. Knock-down of EZH2 inhibited liver metastasis of pancreatic cancer in vivo. EZH2 has a crucial role in tumor growth and liver metastasis of pancreatic cancer.

Glucose-regulated protein 78 is an intracellular antiviral factor against hepatitis B virus

Hepatitis B virus (HBV) infection is a global public health problem that plays a crucial role in the pathogenesis of chronic hepatitis, cirrhosis, and hepatocellular carcinoma. However, the pathogenesis of HBV infection and the mechanisms of host-virus interactions are still elusive. In this study, two-dimensional gel electrophoresis and mass spectrometry-based comparative proteomics were applied to analyze the host response to HBV using an inducible HBV-producing cell line, HepAD38. Twenty-three proteins were identified as differentially expressed with glucose-regulated protein 78 (GRP78) as one of the most significantly up-regulated proteins induced by HBV replication. This induction was further confirmed in both HepAD38 and HepG2 cells transfected with HBV-producing plasmids by real time RT-PCR and Western blotting as well as in HBV-infected human liver biopsies by immunohistochemistry. Knockdown of GRP78 expression by RNA interference resulted in a significant increase of both intracellular and extracellular HBV virions in the transient HBV-producing HepG2 cells concomitant with enhanced levels of hepatitis B surface antigen and e antigen in the culture medium. Conversely overexpression of GRP78 in HepG2 cells led to HBV suppression concomitant with induction of the positive regulatory circuit of GRP78 and interferon-beta1 (IFN-beta1). In this connection, the IFN-beta1-mediated 2',5'-oligoadenylate synthetase and RNase L signaling pathway was noted to be activated in GRP78-overexpressing HepG2 cells. Moreover GRP78 was significantly down-regulated in the livers of chronic hepatitis B patients after effective anti-HBV treatment (p = 0.019) as compared with their counterpart pretreatment liver biopsies. In conclusion, the present study demonstrates for the first time that GRP78 functions as an endogenous anti-HBV factor via the IFN-beta1-2',5'-oligoadenylate synthetase-RNase L pathway in hepatocytes. Induction of hepatic GRP78 may provide a novel therapeutic approach in treating HBV infection.

Proteomic identification of molecular targets of gambogic acid: role of stathmin in hepatocellular carcinoma

Gamboge has been developed as an injectable drug for cancer treatment in China. In this study, the inhibition ratio and their IC(50) values of two derivatives from Gamboge in hepatocellular carcinoma (HCC) were determined. Proteomic approach was employed to reveal the target proteins of these two derivatives, gambogic acid (GA), and gambogenic acid (GEA). HCC cells were cultured under varied conditions with the addition of either GA or GEA. Twenty differentially expressed proteins were identified and the four most distinctly expressed proteins were further validated by Western blotting. GA and GEA revealed inhibitory effects on HCC cell proliferation. The expression of cyclin-dependent kinase 4 inhibitor A and guanine nucleotide-binding protein beta subunit 1 were upregulated by both xanthones, whilst the expression of 14-3-3 protein sigma and stathmin 1 (STMN1) were downregulated. Furthermore, overexpression of STMN1 in HCC cells decreased their sensitivity, whilst small interfering RNAs targeting STMN1 enhanced their sensitivity to GA and GEA. In conclusion, our study suggested for the first time that STMN1 might be a major target for GA and GEA in combating HCC. Further investigation may lead to a new generation of anticancer drugs exerting synergistic effect with conventional therapy, thus to promote treatment efficacy.

Proteomic identification of LASP-1 down-regulation after RNAi urokinase silencing in human hepatocellular carcinoma cells

In human hepatocellular carcinoma (HCC), the high expression of urokinase-type plasminogen activator (uPA) is an unfavorable prognostic factor and a therapeutic target. To identify the downstream effects of uPA silencing by RNA interference, we studied proteome modifications of uPA-inhibited SKHep1C3 cells, an HCC-derived cell line. The study with two-dimensional difference gel electrophoresis and matrix-assisted laser desorption/ionization-time of flight-mass spectrometry showed Lim and SH3 protein 1 (LASP-1), cytokeratin 1 (CK-1), cytokeratin 10 (CK-10), and heterogeneous nuclear ribonucleoprotein H1 down-modulation after uPA inhibition. LASP-1, CK-1, and CK-10 are involved in cytoskeleton dynamics as heterogeneous nuclear ribonucleoprotein H1 takes part in the mRNA processing and stability. We first confirmed the proteomic data by Western blot and immunoflorescence and then explored the link between uPA and LASP-1. The ectopic expression of uPA and LASP-1 supported the proteomic results and showed that uPA up-regulation increased LASP-1 expression and that both were implicated in SKHep1C3 motility. siRNA LASP-1 inhibition showed that LASP-1 was involved in actin microfilaments organization of SKHep1C3 cells. The disruption of the actin microfilaments after LASP-1 depletion increased uPA secretion and SKHep1C3 motility. Our results would suggest the hypothesis that uPA and LASP-1 expression may be coordinated in HCC-derived cells. In summary, the proteomic identification of a set of uPA downstream proteins provides new insight into the function of uPA in HCC cells.

Sustained JNK1 activation is associated with altered histone H3 methylations in human liver cancer

BACKGROUND/AIMS

Aberrant c-Jun N-terminal kinase (JNK) activation has been linked to hepatocellular carcinoma (HCC) in mouse models. It remains unclear whether JNK activation plays an important role in human HCC and, if so, how JNK signaling contributes to the initiation or progression of HCC.

METHODS

The JNK activation, global gene expression, and the status of histone H3 methylations were measured in 31 primary human hepatocellular carcinoma (HCC) samples paired with the adjacent non-cancerous (ANC) tissues.

RESULTS

Enhanced JNK1 activation was noted in 17 out of 31 HCC samples (55%) relative to the corresponding ANC tissues, whereas JNK2 activation was roughly equal between HCC and ANC tissues. This enhancement in JNK1 activation is associated with an increased tumor size and a lack of encapsulation of the tumors. In addition, an association of JNK1 activation with the histone H3 lysines 4 and 9 tri-methylation was observed in the HCC tissues, which leads to an elevated expression of genes regulating cell growth and a decreased expression of the genes for cell differentiation and the p450 family members in HCC.

CONCLUSIONS

These results, thus, suggest that JNK1 plays important roles in the development of human HCC partially through the epigenetic mechanisms.

Down-regulation of stathmin is required for TGF-beta inducible early gene 1 induced growth inhibition of pancreatic cancer cells

Transforming growth factor-beta (TGF-beta) inducible early gene 1 (TIEG1) is known to induce apoptosis in TGF-beta sensitive pancreatic cancer cells, yet its effect on TGF-beta resistant cancer cells remains unclear. In this study, TIEG1 was found to induce apoptosis in TGF-beta resistant cancer cells and concurrently enhanced gemcitabine chemosensitivity. Down-regulation of stathmin was noted to associate with TIEG1 expression, whilst ectopic overexpression of stathmin prevented TIEG1 mediated growth inhibition of tumor cells. Small interfering RNAs targeting stathmin inhibited pancreatic cancer cell growth. These suggest that stathmin is a downstream target of TIEG1.

Advance in proteomic study of hepatocellular carcinoma

At present, studies of hepatocellular carcinoma focus on investigating the molecular mechanism of carcinogenesis, development, metastasis and reccurrence and seeking biological markers for early diagnosis and metastasis prediction and targets for interfering therapy. In the post-genome era, proteomics provides novel insights into the research of hepatocellular carcinoma, which is controlled by multi-genes and multi-proteins. In this paper we reviewed the recent progress in proteomic study of hepatocellular carcinoma.

Effects of neonatal resveratrol exposure on adult male and female reproductive physiology and behavior

Resveratrol (RES) is a phytoestrogen that has the ability to bind to estrogen receptors (ERs) and evoke biological effects that parallel those exerted by endogenous and synthetic estrogens. We have shown in previous studies that adult female rats acutely exposed to RES exhibit estrous cycle irregularity, ovarian hypertrophy, and alterations in sociosexual behavior. The present experiment characterizes the prolonged effects of maternal RES exposure throughout the lactational period on subsequent behavior, reproductive tissues, and brain morphology of the adult offspring. During adulthood, female offspring exposed to RES throughout nursing exhibited reduced body weight and increased ovarian weight, but exhibited normal estrous cyclicity and sociosexual behavior, without changes in the volume of the sexually dimorphic nucleus of the preoptic area or the anteroventral periventricular nucleus of the hypothalamus. During adulthood, males exposed to RES throughout nursing exhibited decreased body weight and plasma testosterone concentration, increased testicular weight, and reduced sociosexual behavior. These males also had significantly smaller sexually dimorphic nucleus of the preoptic area volumes and larger anteroventral periventricular nucleus volumes compared to male controls. These data suggest that postnatal exposure to RES may affect estrogenic activity in specific peripheral tissues (e.g., the gonads), while inducing antiestrogenic effects in the brain. Thus, the present study supports recent in vitro and in vivo findings that RES differs from most other phytoestrogens by acting as a possible mixed ER agonist/antagonist, depending on the tissue-specific availability of ER subtypes that are preferentially localized in specific brain regions and throughout the reproductive tract. More importantly these data indicate that maternal consumption of phytoestrogens during lactation can have lasting effects on the offspring that may not become apparent until they reach adulthood.