Identification of CD14 as a potential biomarker of hepatocellular carcinoma using iTRAQ quantitative proteomics.

Hepatocellular carcinoma (HCC) is one of the most common malignant tumors without effective diagnostic biomarkers. This study intended to dynamically analyze serum proteomics in different pathological stages of liver diseases, and discover potential diagnostic biomarkers for early HCC. Patients with hepatitis B virus (HBV) infection, liver cirrhosis (LC), or HCC together with healthy controls (HC) were enrolled. Proteins differentially expressed between groups were screened using isobaric tagging for relative and absolute quantitation (iTRAQ), and promising HCC biomarker candidates were subjected to bioinformatics analysis, including K-means clustering, gene ontology (GO) and string network analysis. Potential biomarkers were validated by Western blotting and enzyme-linked immunosorbent assay (ELISA), and their diagnostic performance was evaluated using receiver operating characteristic (ROC) curve analysis. Finally, 93 differentially expressed proteins were identified, of which 43 differed between HBV and HC, 70 between LC and HC, and 51 between HCC and HC. Expression levels of gelsolin (GELS) and sulfhydryl oxidase 1 (QSOX1) varied with disease state as follows: HC < HBV < LC < HCC. The reverse trend was observed with CD14. These iTRAQ results were confirmed by Western blotting and ELISA. Logistic regression and ROC curve analysis identified the optimal cut-off for alpha-fetoprotein (AFP), CD14 and AFP/CD14 was 191.4 ng/mL (AUC 0.646, 95%CI 0.467-0.825, sensitivity 31.6%, specificity 94.4%), 3.16 ng/mL (AUC 0.760, 95%CI 0.604-0.917, sensitivity 94.7%, specificity 50%) and 0.197 ng/mL (AUC 0.889, 95%CI 0.785-0.993, sensitivity 84.2%, specificity 83.3%) respectively. In conclusion, Assaying CD14 levels may complement AFP measurement for early detection of HCC.

Glycosylation patterns and PHA-E-associated glycoprotein profiling associated with early hepatic encephalopathy in Chinese hepatocellular carcinoma patients.

Hepatic encephalopathy (HE) as a severe neuropsychiatric complication is commonly present in the end stage of Hepatocellular Carcinoma (HCC). However, widely accepted biomarkers for diagnosing early HE are still absent. Here, we screened glycosylation patterns of serum proteins from Chinese HCC patients with or without early HE by lectin microarray. Then, phaseolus vulgaris erythroagglutinin (PHA-E) as a lectin binding with bisecting GlcNAc structure which was significantly decreased in sera from Chinese HCC patients with early HE, was chosen to perform lectin affinity chromatography, following by in-gel digestion, Mass Spectrometry (MS) analysis and bioinformatics analysis. Here we found, 13 lectins showed statistically significant reduction suggesting GalNAc, terminal α-1,3 Man, bisecting GlcNAc, (GlcNAc)n, O-GlcNAc, Neu5Ac, tetra-antennary complex-type N-glycan and GalNAc α/ß1-3/6 Gal were decreased in serum glycoproteins from Chinese HCC patients with early HE. Furthermore, a total of 141 PHA-E-associated glycoproteins were identified in MS, of which 12 serum glycoproteins only in Chinese HCC patients without early HE and 26 serum glycoproteins only in Chinese HCC patients with early HE. In addition, bioinformatics analysis revealed the PHA-E-associated serum glycoproteins only in Chinese HCC patients with early HE might be related to early HE occurrence through p38 MAPK signaling pathway and MAPK/ERK signaling pathway. Collectively, this was the first glycomics study of serum proteins in HCC patients with early HE and it could provide a database for discovering and developing serum biomarkers to identify and predict early HE in HCC patients.

Genome-wide screen of ovary-specific DNA methylation in polycystic ovary syndrome.

OBJECTIVE: To compare genome-wide DNA methylation profiles in ovary tissue from women with polycystic ovary syndrome (PCOS) and healthy controls. DESIGN: Case-control study matched for age and body mass index. SETTING: University-affiliated hospital. PATIENT(S): Ten women with PCOS who underwent ovarian drilling to induce ovulation and 10 healthy women who were undergoing laparoscopic sterilization, hysterectomy for benign conditions, diagnostic laparoscopy for pelvic pain, or oophorectomy for nonovarian indications. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Genome-wide DNA methylation patterns determined by immunoprecipitation and microarray (MeDIP-chip) analysis. RESULT(S): The methylation levels were statistically significantly higher in CpG island shores (CGI shores), which lie outside of core promoter regions, and lower within gene bodies in women with PCOS relative to the controls. In addition, high CpG content promoters were the most frequently hypermethylated promoters in PCOS ovaries but were more often hypomethylated in controls. Second, 872 CGIs, specifically methylated in PCOS, represented 342 genes that could be associated with various molecular functions, including protein binding, hormone activity, and transcription regulator activity. Finally, methylation differences were validated in seven genes by methylation-specific polymerase chain reaction. These genes correlated to several functional families related to the pathogenesis of PCOS and may be potential biomarkers for this disease. CONCLUSION(S): Our results demonstrated that epigenetic modification differs between PCOS and normal ovaries, which may help to further understand the pathophysiology of this disease.

The high expressed serum soluble neural cell adhesion molecule, a high risk factor indicating hepatic encephalopathy in hepatocelular carcinoma patients.

OBJECTIVE: To investigate whether the expression of serum soluble neural cell adhesion molecule (sNCAM) is associated with hepatic encephalopathy (HE) in hepatocelular carcinoma (HCC) patients. MATERIALS AND METHODS: The Oncomine Cancer Microarray database was used to determine the clinical relevance of NCAM expression in different kinds of human cancers. Sera from 75 HCC cases enrolled in this study were assessed for expression of sNCAM by enzyme linked immunosorbent assay (ELISA). RESULTS: Dependent on the Oncomine Cancer Microarray database analysis, NCAM was down regulated in 10 different kinds of cancer, like bladder cancer, brain and central nervous system cancer, while up-regulated in lung cancer, uterine corpus leiomyoma and sarcoma, compared to normal groups. Puzzlingly, NCAM expression demonstrated no significant difference between normal and HCC groups. However, we found by quantitative ELISA that the level of sNCAM in sera from HCC patients with HE (347.4±151.9 ng/ml) was significantly more up-regulated than that in HCC patients without HE (260.3±104.2 ng/ml), the p-value being 0.008. sNCAM may be an important risk factor of HE in HCC patients, the correlation coefficients was 0.278 (P< 0.05) on rank correlation analysis. CONCLUSIONS: This study highlights that up-regulated level of serum sNCAM is associated with HE in HCC patients and suggests that the high expression can be used as an indicator.

Dynamic expression patterns of differential proteins during early invasion of hepatocellular carcinoma.

BACKGROUND: Tumor cell invasion into the surrounding matrix has been well documented as an early event of metastasis occurrence. However, the dynamic expression patterns of proteins during early invasion of hepatocellular carcinoma (HCC) are largely unknown. Using a three-dimensional HCC invasion culture model established previously, we investigated the dynamic expression patterns of identified proteins during early invasion of HCC. MATERIALS AND METHODS: Highly metastatic MHCC97H cells and a liver tissue fragment were long-term co-cultured in a rotating wall vessel (RWV) bioreactor to simulate different pathological states of HCC invasion. The established spherical co-cultures were collected on days 0, 5, 10, and 15 for dynamic expression pattern analysis. Significantly different proteins among spheroids at different time points were screened and identified using quantitative proteomics of iTRAQ labeling coupled with LC-MS/MS. Dynamic expression patterns of differential proteins were further categorized by K-means clustering. The expression modes of several differentially expressed proteins were confirmed by Western blot and qRT-PCR. RESULTS: Time course analysis of invasion/metastasis gene expressions (MMP2, MMP7, MMP9, CD44, SPP1, CXCR4, CXCL12, and CDH1) showed remarkable, dynamic alterations during the invasion process of HCC. A total of 1,028 proteins were identified in spherical co-cultures collected at different time points by quantitative proteomics. Among these proteins, 529 common differential proteins related to HCC invasion were clustered into 25 types of expression patterns. Some proteins displayed significant dynamic alterations during the early invasion process of HCC, such as upregulation at the early invasion stage and downregulation at the late invasion stage (e.g., MAPRE1, PHB2, cathepsin D, etc.) or continuous upregulation during the entire invasion process (e.g., vitronectin, Met, clusterin, ICAM1, GSN, etc.). CONCLUSIONS: Dynamic expression patterns of candidate proteins during the early invasion process of HCC facilitate the discovery of new molecular targets for early intervention to prevent HCC invasion and metastasis.

A specific cholesterol metabolic pathway is established in a subset of HCCs for tumor growth.

The liver plays a central role in cholesterol homeostasis. It exclusively receives and metabolizes oxysterols, which are important metabolites of cholesterol and are more cytotoxic than free cholesterol, from all extrahepatic tissues. Hepatocellular carcinomas (HCCs) impair certain liver functions and cause pathological alterations in many processes including cholesterol metabolism. However, the link between an altered cholesterol metabolism and HCC development is unclear. Human ACAT2 is abundantly expressed in intestine and fetal liver. Our previous studies have shown that ACAT2 is induced in certain HCC tissues. Here, by investigating tissue samples from HCC patients and HCC cell lines, we report that a specific cholesterol metabolic pathway, involving induction of ACAT2 and esterification of excess oxysterols for secretion to avoid cytotoxicity, is established in a subset of HCCs for tumor growth. Inhibiting ACAT2 leads to the intracellular accumulation of unesterified oxysterols and suppresses the growth of both HCC cell lines and their xenograft tumors. Further mechanistic studies reveal that HCC-linked promoter hypomethylation is essential for the induction of ACAT2 gene expression. We postulate that specifically blocking this HCC-established cholesterol metabolic pathway may have potential therapeutic applications for HCC patients.

Promoter methylation of CYP19A1 gene in Chinese polycystic ovary syndrome patients.

AIMS: This study aimed to examine the methylation status of the CYP19A1 promoter region in Chinese polycystic ovary syndrome (PCOS) patients. METHODS: A case-control study was designed that involved 10 PCOS patients and 10 controls. Ovary tissues obtained from 10 women with PCOS and 10 healthy controls were matched for body mass index and age. Methylation of CYP19A1 promoter was detected by methylation-specific PCR. CYP19A1 expression was measured by real-time PCR and Western blotting. RESULTS: The methylation level of CYP19A1 promoter in PCOS samples was significantly higher than in controls (0.698 ± 0.192 vs. 0.210 ± 0.064, p < 0.01). A significant downregulation of CYP19A1 mRNA and protein expression levels was observed in PCOS ovary tissues. Furthermore, the scatter plot revealed that promoter methylation was inversely correlated with CYP19A1 mRNA level (Pearson's correlation -0.820, p < 0.01). CONCLUSION: CYP19A1 expression is frequently repressed in PCOS ovaries due to the promoter hypermethylation. CYP19A1 promoter hypermethylation may play a key role in the pathogenesis of PCOS. © 2013 S. Karger AG, Basel.

SUOX is a promising diagnostic and prognostic biomarker for hepatocellular carcinoma.

BACKGROUND & AIMS: To investigate diagnostic and prognostic values of sulfite oxidase (SUOX) in patients with hepatocellular carcinoma (HCC) who underwent curative resection. METHODS: We investigated immunohistochemically the expression dynamics of SUOX, aldo-ketoreductase family 1 member B10 (AKR1B10) and CD34 at different stages of HCC. The differential diagnostic performance of three markers or their combinations in high-grade dysplastic nodules (HGDNs) and well-differentiated small HCC (WD-sHCC) were investigated by logistic regression models and validated in an independent testing set. Overall survival (OS) and time to recurrence (TTR) were evaluated in 300 patients with HCC as the testing cohort, and validated in 198 patients with HCC. RESULTS: SUOX was decreased and AKR1B10 and CD34 were increased with the stepwise progression of hepatocarcinogenesis. For differential diagnosis of WD-sHCC from HGDNs, the sensitivity and specificity of the SUOX+AKR1B10+CD34 combination for WD-sHCC detection were 93.8% and 95.2%, respectively, and overall accuracy was much higher than any of the three individual markers and two marker combinations. In addition, SUOX, but not AKR1B10 and CD34, was an independent prognostic factor for OS and TTR, and showed better correlation with OS and TTR if combined with serum α-fetoprotein (AFP) for both the testing and validation cohorts. CONCLUSIONS: SUOX+AKR1B10+CD34 combination could make a substantial contribution to hepatic immunopathological diagnosis to distinguish WD-sHCC from HGDNs. Meanwhile, SUOX combined with serum AFP may predict postoperative outcome and tumor recurrence risk.

NANOG promotes liver cancer cell invasion by inducing epithelial-mesenchymal transition through NODAL/SMAD3 signaling pathway.

NANOG is a major transcription factor essential to the stem cell self-renewal and is associated with tumor malignancy, but the NANOG signaling in cancer metastasis is still elusive. In this study, we determined the expression of NANOG in hepatocellular carcinoma (HCC) and investigated its underlying mechanism in the metastasis of HCC. The expression levels of NANOG were examined in tumor tissues by immunohistochemistry. Functional effect of NANOG was investigated both in vivo and in vitro. Our data shows that high level of NANOG expression correlates with metastasis and low survival rate in HCC. HCC cells overexpressing NANOG are characterized by active epithelial-mesenchymal transition (EMT), and exhibit increased ability of invasion, soft agar colonization, sphere formation and drug resistance, whereas SB-431542, an antagonist of activin receptor-like kinase (ALK) receptors, attenuates EMT and invasion of HCC cells. NANOG activates NODAL and CRIPTO-1 to promote SMAD3 phosphorylation and SNAIL expression. The transcriptional activity of NODAL gene is dependent on two NANOG binding motifs in its promoter region. This study shows a significant correlation between the NANOG expression and the expression of NODAL, P-SMAD3 or SNAIL, and the combination of NANOG and P-SMAD3 is a potential predictor of poor prognosis of HCC. Additionally, cells in the tumor edge area displays higher NANOG expression than cells in the tumor center. These results present novel mechanistic insight into an important role of NANOG in HCC metastasis, and suggest a potential application of NANOG in HCC prognosis and treatment.

A novel panel of biomarkers in distinction of small well-differentiated HCC from dysplastic nodules and outcome values.

BACKGROUND: Differential diagnosis of high-grade dysplastic nodules (HGDN) and well-differentiated hepatocellular carcinoma (WDHCC) represents a challenge to experienced hepatic clinicians, radiologists and hepatopathologists. METHODS: The expression profiles of aminoacylase-1 (ACY1), sequestosome-1 (SQSTM1) and glypican-3 (GPC3) in low-grade dysplastic nodules (LGDN), HGDN and WDHCC were assessed by immunohistochemistry. The differential diagnostic performances of these three markers alone and in combination for HGDN and WDHCC were investigated by logistic regression models (HGDN = 21; WDHCC = 32) and validated in an independent test set (HGDN, n = 21; WDHCC n = 24). Postoperative overall survival and time to recurrence were evaluated by univariate and multivariate analyses in an independent set of 500 patients. RESULTS: ACY1, SQSTM1 and GPC3 were differentially expressed in each group. For the differential diagnosis of WDHCC from HGDN, the sensitivity and specificity of the combination of ACY1 + SQSTM1 + GPC3 for detecting WDHCC were 93.8% and 95.2% respectively in the training set, which were higher than any of the three two-marker combinations. The validities of the four diagnostic models were further confirmed in an independent test set, and corresponding good sensitivity and specificity were observed. Interestingly, GPC3 expression in HCC tissues combined with serum α-fetoprotein (AFP) was found to be an independent predictor for overall survival and time to recurrence. CONCLUSIONS: ACY1 + SQSTM1 + GPC3 combination represents a potentially valuable biomarker for distinguishing between WDHCC and HGDN using immunohistochemistry. Meanwhile, low GPC3 staining combined with positive serum AFP may play a practical role in predicting poor postoperative outcome and high tumor recurrence risk.

Genetic variants in STAT4 and HLA-DQ genes confer risk of hepatitis B virus-related hepatocellular carcinoma.

To identify genetic susceptibility loci for hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC) in the Chinese population, we carried out a genome-wide association study (GWAS) in 2,514 chronic HBV carriers (1,161 HCC cases and 1,353 controls) followed by a 2-stage validation among 6 independent populations of chronic HBV carriers (4,319 cases and 4,966 controls). The joint analyses showed that HCC risk was significantly associated with two independent loci: rs7574865 at STAT4, P(meta) = 2.48 × 10(-10), odds ratio (OR) = 1.21; and rs9275319 at HLA-DQ, P(meta) = 2.72 × 10(-17), OR = 1.49. The risk allele G at rs7574865 was significantly associated with lower mRNA levels of STAT4 in both the HCC tissues and nontumor tissues of 155 individuals with HBV-related HCC (P(trend) = 0.0008 and 0.0002, respectively). We also found significantly lower mRNA expression of STAT4 in HCC tumor tissues compared with paired adjacent nontumor tissues (P = 2.33 × 10(-14)).

[Applicability of the multiplex quantitative antibody array system for early diagnosis of hepatocellular carcinoma].

OBJECTIVE: To develop an early and accurate detection method for hepatocellular carcinoma (HCC) based on detection of tumor-associated serum markers using a multiplex quantitative antibody array. METHODS: The double-antibody sandwich principle was used to establish an antibody array composed of eight cancer-related serum markers, including alpha-fetoprotein (AFP), hepatocyte growth factor (HGF), insulin-like growth factor (IGF), interleukin-6 (IL-6), interleukin-8 (IL-8), interleukin-10 (IL-10), transforming growth factor-beta 1 (TGF-b1), and vascular endothelial growth factor (VEGF). Serum samples from 160 cases of clinically diagnosed HCC and from 58 cases of liver cirrhosis (LC; controls) were obtained to test the array. Sixty percent of the samples were randomly selected for use as the training set (HCC, n = 96; LC, n = 36), and the remaining 40% was used as the test set (HCC, n = 64; LC, n = 22). The SPSS statistical software was used to perform logistic regression analysis and to create a diagnostic model. RESULTS: When used with the training set, the model had sensitivity of 93.3%, specificity of 83.3%, and accuracy of 90.9%. When used with the test set, the model had sensitivity of 89.0%, specificity of 77.3%, and accuracy of 86.0%. The traditional serum AFP value (cut-off value of 20 ng/mL) showed 70.0% diagnostic sensitivity, 59.0% specificity, and 64.0% accuracy. CONCLUSION: The newly developed multiplex quantitative antibody detection system has high sensitivity and specificity. The diagnostic model with AFP and seven other cancer-related factors was superior to the traditional AFP only approach for early diagnosis of liver cancer, indicating its potential clinical value.

[The effects of stathmin on cell proliferation and tumor-related genes expressions in HCCLM3 cells].

To explore the biological function and possible underlying mechanism of stathmin gene during hepatocarcinogenesis. Three pairs of chemically synthesized small interfering RNA (siRNA) targeting on stathmin were transfected into HCCLM3 by LipofectamineTM 2000. After confirming the interfering effects of stathmin siRNAs through reverse transcription PCR and Western blotting, the HCCLM3 cells proliferation and apoptosis were detected by cell count kit-8 (CCK-8) and flow cytometry analysis, and the expressions of tumor-related genes (c-myc, c-fos, p53, etc) were observed by real-time PCR. Stathmin expression was effectively inhibited up to 90% by stathmin silencing in HCCLM3 cells (P is less than to 0.05) . By using CCK8 assay, it was shown that HCCLM3 cells proliferation were obviously depressed by 13.04%+/-0.10%, 28.10%+/-0.41% and 37.36%+/-2.15% at the time point of 24 h, 48 h and 72 h with the comparison to Mock group (F = 4.21, P is less than to 0.05). The results of flow cytometry demonstrated that the percentage of apoptotic cells was increased to 25.11%+/-1.62% in RNAi group, compared with 9.20 %+/-0.64 % in Mock group (F = 44.67, P is less than to 0.01). The results of real-time PCR showed that oncogenes c-myc and c-fos expressions were repressed, proliferation-associated gene ki-67 was down-regulated, and apoptosis-promoting gene caspase-3, bax and p53 were induced (P is less than to 0.05). Stathmin may promote cell proliferation, inhibit cell apoptosis and induce malignant transformation of hepatocytes by regulating some tumor-related genes expressions.

iTRAQ-2DLC-ESI-MS/MS based identification of a new set of immunohistochemical biomarkers for classification of dysplastic nodules and small hepatocellular carcinoma.

The study aims to develop novel clinical immunohistochemical biomarkers for distinguishing small hepatocellular carcinoma (sHCC) from dysplastic nodules (DN). iTRAQ-2DLC-ESI-MS/MS technique was used to screen immunohistochemical biomarkers between precancerous lesions (liver cirrhosis and DN) and sHCC. A total of 1951 proteins were quantified, including 52 proteins upregulated in sHCC and 95 proteins downregulated in sHCC by at least 1.25- or 0.8-fold at p < 0.05. The selected biomarker candidates were further verified using Western blotting and immunohistochemistry. Furthermore, receiver operation characteristics (ROC) curves and logistic regression model were carried out to evaluate the diagnostic values of the biomarkers. Finally, aminoacylase-1 (ACY1) and sequestosome-1 (SQSTM1) were chosen as novel candidate biomarkers for distinction of sHCC from DN. A constructed logistic regression model included ACY1, SQSTM1, and CD34. The sensitivity and specificity of this model for distinguishing sHCC from DN was 96.1% and 96.7%. In conclusion, ACY1 and SQSTM1 were identified as novel immunohistochemical biomarkers distinguishing sHCC from DN. In conclusion, expression levels of CD34, ACY1, and SQSTM1 can be used to establish an accurate diagnostic model for distinction of sHCC from DN.

Induced pluripotent cancer cells: progress and application.

Induced pluripotent stem (iPS) cells are a group of pluripotent stem cells artificially derived from non-pluripotent cells typically by a forced expression of specific transcription factors. Generation of cancer-specific iPS cells, also called induced pluripotent cancer (iPC) cells, provides valuable experimental platform to model oncogenesis and holds great potential in the fields of drug screening. However, iPC cells are harder to achieve than normal iPS cells probably because of the special genetic and epigenetic states of cancer cells. To help overcome this hurdle of iPC research and to prospect this promising field, this review emphasizes the experimental issues of reprogramming cancer into iPC cells, and discusses the potential of iPC cells in cancer research.

[Relationship between CD44 expression or glycosylation and hepatocellular carcinoma metastasis].

OBJECTIVE: To explore the relationship of CD44 expression or glycosylation and hepatocellular carcinoma (HCC) metastasis. METHODS: IHC, Quantum dots detection, RT-PCR, Western blot, Cellular immune fluorescence and MS-PCR were used to identify CD44 expression in HCC samples and a series of human HCC cell lines with different metastatic potentials. Lectin array was used to reveal the relationship of CD44v6 glycosylation and human HCC metastasis. RESULTS: Immunohistochemistry analysis showed that CD44v6 was mainly distributed on the cell membrane, while CD44S immunoreactivity was prominently in the cytoplasm, CD44v3 and CD44v4/5 were in cytoplasm on membrane. Among CD44S and those CD44 variants, only the expression of CD44v6 was higher in metastasis HCC samples as compared to that in non-metastasis group (x²=8.828, P less than 0.05). This result was also re-confirmed by the result of Quantum dots (t = 2.392, P < 0.05) and serum detection (t = 2.56, P < 0.05). We found completely methylation of CD44v6 gene in Hep3B and incomplete methylation in MHCC97H and MHCC97L cell lines with metastatic potentials. The lectin affinity assay indicated that lectin MAL, SNA and WGA showed more affinity to MHCC97H and MHCC97Lcell lines than that of the non-metastatic Hep3B cell lines. CONCLUSIONS: CD44v6 over-expression presents a positive correlation with HCC metastatic potential, which may be associated with DNA methylation level in promoter sequence. The increasing sialic acid modified glycan of CD44v6 might be related to HCC metastatic ability.

[Identification of metastasis-related osteopontin expression and glycosylation in hepatocellular carcinoma].

OBJECTIVE: To test expression level and glycosylation level of OPN in HCC cell lines with different metastatic potential and HCC tissues, and investigate the correlation between the glycosylation change and the liver cancer transporting as well as its significance. METHODS: The level of OPN expression in liver cancer tissue(6 cases of non-metastasis and 7 cases of metastasis)as well as HCC cell lines with different metastatic potential (L02, Hep3B, MHCC97L, MHCC97H, HCCLM3, HCCLM6)was identified by immunohistochemistry and Western Blot, and then OPN was purified from HCC tissues by immunoprecipitation, followed by glycosylation detection of OPN from non-metastatic and metastatic HCC tissues by multiple lectin blot. Data were analyzed by t-test and variance analysis. RESULTS: Different levels of OPN expression were observed in HCC cell lines with different metastatic potential (F = 5.04, P = 0.008). Additionally, OPN expression level in HCC tissues with metastasis was higher than that in non-metastasis group (t = 2.447, P < 0.05). Relative optical density value was 0.69 ± 0.21 and 0.45 ± 0.14 respectively. OPN in liver cancer tissue was successfully purified using immunoprecipitation. Followed lectin blotting result showed that OPN protein in metastasis group showed lower affinity to MAL, PHAE, DSA, ConA as compared with that in non-metastasis group (P < 0.05). CONCLUSIONS: The expression of OPN was positively correlated with the enhanced metastasis potential of HCC. OPN from metastasis HCC tissues presented lower level of some specific glycan structures such as a2, 3- sialic acid, bisecting GlcNAc, biantennary, muti-antennary and high mannose type N-glycan structure. This study not only indicates the role of OPN in HCC metastasis for the first time, but also provide experimental support for the mechanism of the function of OPN in the transportation of liver cancer cells as well as offer potential target for clinical treatment.

[Effects of AKR1B10 gene silence on the growth and gene expression of HCC cell line MHCC97H].

OBJECTIVE: To explore the biological function and possible underlying mechanism of aldo-keto reductase family 1 member B10 (AKR1B10) gene during hepatocarcinogenesis. METHODS: A pair of chemically synthesized small interfering RNA (siRNA) targeting on AKR1B10 was transfected into liver cancer cell line MHCC97H by LipofectamineTM 2000. After confirming the interfering effects of AKR1B10-siRNAs through Quant SYBR Green polymerase chain reaction (Real-time PCR), Western blot and enzymatic activity assay, the capabilities of proliferation and apoptosis of the transfected cells were observed by CCK-8 assay and flow cytometry analysis, and the expressions of a group of tumor-related gene such as c-myc, c-fos, N-ras were observed through Real-time PCR. RESULTS: The expressions of AKR1B10 and the enzymatic activity were down-regulated significantly in AKR1B10-siRNA-transfected cells. Compared with mock and blank control groups, cell growth in AKR1B10-siRNA-transfected group was inhibited by 26.6%+/-3.1% at 72h after transfection. The ratio of apoptotic cells was 37.3%+/-1.0% in AKR1B10-siRNA-transfected group, which was significantly higher than that in mock and blank control groups (P < 0.01). Real-time PCR showed that the expressions of oncogene c-myc, c-fos and N-ras, and the proliferation-associated gene ki-67 were down-regulated in AKR1B10-siRNA-transfected cells, while the expressions of apoptosis-promoting gene caspas-3 and bax were up-regulated. CONCLUSIONS: AKR1B10 might promote proliferation, inhibit apoptosis and then induce malignant transformation of hepatocytes by regulating the expression level of some tumor-related genes.