Mingbing Xiao

The expressions and clinical significances of tissue and serum galectin-3 in pancreatic carcinoma.

PurposeGalectin-3, a member of the beta-galactoside-binding protein family, is involved in many biological processes, including cell proliferation, regulating cell cycle, angiogenesis, tumorigenesis, metastasis, etc. The aim of this study is to elucidate the relationship between galectin-3 and clinicopathological variables and to evaluate the clinical significance of serum galectin-3 in the diagnosis of pancreas carcinoma.MethodsGalectin-3 expression in 78 pairs of pancreatic carcinoma tissues and the adjacent nontumorous tissues was tested by immunohistochemistry. The relationship between galectin-3 expression and clinical variables was analyzed. A sensitive method of time-resolved fluorescence immunological assay (TRFIA) for the detection of galectin-3 was established, and serum galectin-3 in cases with different pancreatic diseases was measured by TRFIA and ELISA. Further we compared the sensitivity and specificity of determining galectin-3, carcinoembryonic antigen (CEA) and carbohydrate antigen199 (CA199) for diagnosis of pancreatic carcinoma and assessed the complementary diagnostic value of galectin-3, CEA and CA199 for pancreatic carcinoma.ResultsImmunohistochemistry showed that galectin-3 expression was significantly higher in the human pancreatic carcinoma tissues than in the adjacent nontumorous tissues. The expression levels were correlated with the differentiation degree with the higher expression in poor differentiation tissues. Serum galectin-3 detected by both TRFIA and ELISA was much higher in patients with pancreatic carcinoma than in other groups. Serum galectin-3 was not correlated with CEA and CA199. Combined determination of these three markers has the complementary diagnostic value for human pancreatic carcinoma and may increase the diagnostic sensitivity to 97.5%.ConclusionsGalectin-3 is overexpressed in pancreatic carcinoma tissues, and it is correlated with the tumor differentiation. Serum galectin-3 is higher in cases with pancreatic carcinoma than in benign pancreatic diseases and healthy persons. Combined determination of serum galectin-3, CEA and CA199 may improve the diagnostic power for pancreatic carcinoma.

S100 family signaling network and related proteins in pancreatic cancer (Review)

The occurrence and development of pancreatic cancer is a complex process convoluted by multi-pathogenies, multi-stages and multi-factors. S100 proteins are members of the S100 family that regulate multiple cellular pathways related to pancreatic cancer progression and metastasis. S100 proteins have a broad range of intracellular and extracellular functions, including the regulation of protein phosphorylation and enzyme activity, calcium homeostasis and the regulation of cytoskeletal components and transcriptional factors. S100 proteins interact with receptor for advanced glycation end-products (RAGE), p53 and p21, which play a role in the degradation of the extracellular matrix (ECM) and metastasis, and also interact with cytoskeletal proteins and the plasma membrane in pancreatic cancer progression and metastasis. S100A11 and S100P are significant tumor markers for pancreatic cancer and unfavorable predictors for the prognosis of patients who have undergone surgical resection. Recently, S100A2 has been suggested to be a negative prognostic biomarker in pancreatic cancer, and the expression of S100A6 may be an independent prognostic impact factor. The expression of S100A4 and S100P is associated with drug resistance, differentiation, metastasis and clinical outcome. This review summarizes the role and significance of the S100 family signaling network and related proteins in pancreatic cancer.

Long non-coding RNA SNHG20 predicts a poor prognosis for HCC and promotes cell invasion by regulating the epithelial-to-mesenchymal transition

BACKGROUND Recently, Accumulating evidence indicates that long noncoding RNAs (lncRNAs) have been shown to have critical regulatory roles in human tumor biology and development. However, the expression pattern and biological function of lncRNA small nucleolar RNA host gene 20 (SNHG20) in hepatocellular carcinoma (HCC) remains largely unknown. METHODS The expression of SNHG20 in 96 paired HCC tissues and cell lines were detected by quantitative real-time PCR (qRT-PCR) analysis. Kaplan-Meier survival analysis and log-rank test was used to reveal the association between SNHG20 expression and the overall survival time in HCC patients. CCK8 cell proliferation and transwell invasion assays were performed to analyze the cell proliferation and cell invasion ability. QRT-PCR and western-blotting analysis were performed to demonstrate the mRNA levels and protein expression of ZEB1, ZEB2 and relative epithelial-to-mesenchymal transition (EMT) markers (E-cadherin, N-cadherin and Vimentin). RESULTS We showed that the expression level of SNHG20 was significantly up-regulated in 96 pairs of HCC tissues and adjacent normal tissues. Higher SNHG20 expression was positively correlated with larger tumor size and advanced TNM stage, and negatively correlated with the over survival (OS) time for HCC patients. In vitro, loss-function assays revealed that knockdown of SNHG20 inhibited cell proliferation and invasion, whereas, gain-of-function promoted cell proliferation and invasion. Furthermore, knockdown of SNHG20 inhibited ZEB1, ZEB2, N-cadherin and Vimentin expression and up-regulated the E-cadherin expression in HCC cells. Mechanistic investigation revealed that SNHG20 could bind to enhancer of zeste homolog 2 (EZH2) and regulated E-cadherin expression. CONCLUSION Our results showed that the SNHG20/EZH2/E-cadhein regulator pathway might contribute to the development of novel therapeutic strategies for HCC patients.

Overexpressed nuclear BAG‐1 in human hepatocellular carcinoma is associated with poor prognosis and resistance to doxorubicin

Bcl‐2‐associated athanogene‐1 (BAG‐1) is a multifunctional anti‐apoptotic protein which regulates an array of cellular processes, including apoptosis, signaling, proliferation, transcription, and cell motility and has been reported to be over‐expressed in a number of human malignancies. To investigate the possible involvement of BAG‐1 in tumorigenesis of hepatocellular carcinoma (HCC), we performed Western blot analysis in eight paired samples of HCC and adjacent peritumoral tissues and immunohistochemistry in 65 paraffin sections of HCC, which both showed an enhanced expression of nuclear BAG‐1 isoform in HCC tissues. Statistical analysis confirmed that overexpression of nuclear BAG‐1 in HCC tissues was significantly associated with histological grading (P < 0.001), poor prognosis (P = 0.004), and was found to be an independent prognostic indicator for HCC (P = 0.023). We also noted that BAG‐1 was overexpressed in four HCC cell lines compared with a normal hepatocyte cell line, and BAG‐1 overexpression increased resistance of HCC cells to doxorubicin, a common chemotherapeutic agent for HCC. Furthermore, we observed that knock down of BAG‐1 with siRNA in HepG2 cells increased the chemosensitivity of cells, a process mediated through inhibition of doxorubicin‐triggered NF‐κB activation; and knock down of BAG‐1 suppressed proliferation and cell cycle transition of HepG2 cells. In consequence, our results for the first time indicated that BAG‐1 was dysregulated in HCC and suppression of BAG‐1 expression which resulted in inhibiting of NF‐κB signaling might be developed into a new strategy in HCC therapy. J. Cell. Biochem. 114: 2120–2130, 2013.

Combined analysis of serum γ-glutamyl transferase isoenzyme II, α-L-fucosidase and α-fetoprotein detected using a commercial kit in the diagnosis of hepatocellular carcinoma.

γ-glutamyl transferase isoenzyme II (GGT-II) is a sensitive biomarker of hepatocellular carcinoma (HCC). However, numerous disadvantages of the traditional manual method affected its application. The commercial kit provided a convenient and fast method for the determination of GGT-II levels. The purposes of the present study were to compare the reproducibility and sensitivity between the manual and commercial kit methods and to evaluate the diagnostic efficiency for HCC with the combined analysis of GGT-II, α-L-fucosidase (AFU) and α-fetoprotein (AFP). In patients with various liver diseases (HCC, liver cirrhosis and chronic hepatitis) and normal subjects, GGT-II was detected by manual and commercial polyacrylamide gel electrophoresis (PAGE). The levels of AFU and AFP were assayed by colorimetry and a chemiluminescence immunoassay, respectively. The commercial PAGE had equal diagnostic efficiency with traditional manual PAGE and no significant differences were observed in intra- and average-gel reproducibility and GGT-II sensitivities between the manual and commercial PAGE (P>0.05). The incidence of GGT-II detected by commercial PAGE in HCC patients was 84.1% and <8% in benign liver disease. The levels of AFU and AFP in the benign liver diseases and normal subjects were lower than those in HCC. According to the cut-off value obtained by receiver operating characteristic curves, a total of 56.6 and 59.3% of HCC patients (64 out of 113 and 67 out of 113) had AFU >636.5 μmol/l h and AFP >44.0 μg/l, respectively. There were no significant correlations between GGT-II and AFU or AFP. Combined detection of GGT-II with AFU or AFP increased the diagnostic sensitivity to 92.9 and 93.8%, respectively. These results suggest that commercial PAGE provides a simple and reproducible method for GGT-II detection. Combined determination of GGT-II with AFU or AFP exhibited superior sensitivity and specificity for the diagnosis of HCC.

The presence of IGHG1 in human pancreatic carcinomas is associated with immune evasion mechanisms.

Objectives: To investigate the expression of Ig&ggr;-1 chain C region (IGHG1) in human pancreatic carcinomas and determine the biological function of IGHG1 expression in immune evasion mechanisms. Methods: Comparative proteomic analysis was used to detect the differential expression of IGHG1 in human pancreatic cancer tissues versus adjacent noncancerous tissues, followed by confirmatory tests including quantitative real-time reverse transcription-polymerase chain reaction, Western blot analysis, immunohistochemistry, and immunofluorescence. A murine pancreatic tumor model was established by transplantation of IGHG1-overexpressing Panc02 cells. The cytotoxic responses of natural killer (NK) cells were assessed with a lactate dehydrogenase release assay. Results: Ig&ggr;-1 chain C region was found to be present in human pancreatic cancer tissues but nearly absent or expressed lower in adjacent noncancerous tissues. In the murine pancreatic tumor model, the tumor growth was significantly accelerated from day 12 to 20 after tumor injection, and the survival time of animals was decreased. Blockage of IGHG1 led to retarded tumor growth and improved survival. The cytotoxicity assay revealed that IGHG1 downregulated the cytotoxic activity of NK cells through inhibition of antibody-dependent cellular cytotoxicity function. Conclusions: The presence of IGHG1 in pancreatic cancer cells might constitute an important element responsible for tumor cell proliferation and immune evasion mechanisms.Abbreviations: IGHG1 - Ig&ggr;-1 chain C region, ADCC - antibody-dependent cellular cytotoxicity, NK cells - natural killer cells, PCR - polymerase chain reaction, LDH - lactate dehydrogenase, CH - constant region of heavy chain

Decreased Expression and Prognostic Role of Mitogen-Activated Protein Kinase Phosphatase 4 in Hepatocellular Carcinoma

PurposeThis study aimed to investigate the potential role and prognostic significance of mitogen-activated protein kinase phosphatase 4 (MKP-4) in the pathology of hepatocellular carcinoma (HCC).MethodsWestern blot analysis and quantitative real-time polymerase chain reaction were performed to detect MKP-4 expression in HCC tissues, pericarcinomatous liver (PCL) tissues, and proliferating HCC cells. The detailed role of MKP-4 was further explored by MKP-4 downregulation in HepG2 cells using small interfering RNA (siRNA). Specimens of 134 HCC patients who had undergone hepatic resection were immunohistochemically evaluated for MKP-4 expression.ResultsMKP-4 protein and mRNA levels were significantly lower in HCC tissues than in PCL tissues. In vitro, its expression was gradually reduced following release of HepG2 cells from serum starvation. The cell counting kit-8 assay and Annexin-V-Fluos staining indicated that MKP-4 knockdown by siRNA in HCC cells enhanced cell survival and inhibited apoptosis. Univariate and multivariate analyses revealed that MKP-4 was a significant predictor for overall survival (OS) and time to recurrence (TTR). High MKP-4 expression was well correlated with prognosis independent of Edmondson grade and microvascular invasion (P < 0.001).ConclusionsMKP-4 expression was downregulated in HCC tissues and proliferating HCC cells and correlated with OS and TTR, which suggested that MKP-4 is a candidate prognostic marker for HCC.

Overexpression of DIXDC1 correlates with enhanced cell growth and poor prognosis in human pancreatic ductal adenocarcinoma

Disheveled-axin (DIX) domain containing 1 (DIXDC1), a protein containing a coiled-coil domain and a DIX domain, is involved in the progression of multiple cancers. However, the role of DIXDC1 in human pancreatic ductal adenocarcinoma (PDAC) remains unclear. In this study, we investigated the role and prognostic value of DIXDC1 in the development of human PDAC. Western blot analysis revealed that DIXDC1 was highly expressed in PDAC tissues and cell lines. Immunohistochemistry on 165 paraffin-embedded sections showed that high expression of DIXDC1 was significantly correlated with tumor size (P = .002), histological differentiation (P = .001), tumor node metastasis (TNM) stage (P = .001), and the proliferation marker Ki-67 (P = .000). Importantly, Kaplan-Meier analysis revealed that high expression of DIXDC1 was obviously correlated with worsened overall survival (P < .001). In vitro, using serum starvation-refeeding experiments, our results suggested that DIXDC1 was up-regulated in proliferating PDAC cells, together with the percentage of cells at the S phase, and was correlated with the expression of cyclin D1. In addition, depletion of DIXDC1 decreased PCNA and cyclin D1 levels. Accordingly, CCK-8, colony formation, and flow cytometry analyses revealed that knocking down DIXDC1 induced growth impairment and G1/S cell cycle arrest in PDAC cells, while overexpression of DIXDC1 led to accelerated cell proliferation and cell cycle progression. On the basis of these results, we propose that DIXDC1 could play an important role in the tumorigenesis of PDAC and serve as a potential therapeutical target to prevent PDAC progression.

S100A11 promotes human pancreatic cancer PANC‑1 cell proliferation and is involved in the PI3K/AKT signaling pathway

S100A11, a member of S100 calcium-binding protein family, is associated with the numerous processes of tumorigenesis and metastasis. In the present study, the role of S100A11, and its possible underlying mechanisms in cell proliferation, apoptosis and cell cycle distribution in human pancreatic cancer were explored. Immunohistochemical analyses of S100A11 and phosphorylated (p)-AKT serine/threonine kinase (AKT) were performed in 30 resected specimens from patients with pancreatic cancer. PANC-1 cells were transfected with pcDNA3.1-S100A11 or treated with 50 µmol/l LY294002 for 48 h. Cell proliferation was determined using a cell counting kit-8 assay, whereas apoptosis and cell cycle distribution were determined by flow cytometry analysis. The mRNA and protein levels of S100A11, and AKT were determined using semi quantitative reverse transcription-polymerase chain reaction and western blot analyses, respectively. Pearson correlation analysis revealed that the expression levels of S100A11 and p-AKT were positively correlated (r, 0.802; P<0.05). Compared with the control group, S100A11 overexpression significantly promoted PANC-1 cell proliferation and reduced the percentage of early apoptotic cells. Flow cytometric analysis indicated that the proportion of PANC-1 cells in the S phase was significantly elevated and cell percentage in the G0/G1 phase declined in response to S100A11 overexpression (all P<0.05). S100A11 overexpression also significantly increased AKT mRNA and p-AKT protein expression levels (both P<0.05). The phosphoinositide 3-kinase (PI3K) inhibitor, LY294002, significantly inhibited PANC-1 cell proliferation, promoted apoptosis and caused G1/S phase arrest in PANC-1 cells (all P<0.05). These findings together suggest that S100A11 promotes the viability and proliferation of human pancreatic cancer PANC-1 cells through the upregulation of the PI3K/AKT signaling pathway. Thus, S100A11 may be considered as a novel drug target for targeted therapy of pancreatic cancer.

Expression pattern of BCCIP in hepatocellular carcinoma is correlated with poor prognosis and enhanced cell proliferation

BCCIP was originally identified as a BRCA2- and CDKN1A- (Cip1/waf1/p21) interacting protein, also known as BCCIP. It has been reported to express in various types of cancers, including colorectal cancer (CRC), astrocytic brain tumors, and glioblastomas. However, the relationship between BCCIP expression and clinicopathological features of hepatocellular carcinoma (HCC) remains to be determined. Herein, we demonstrated that BCCIP was downregulated in clinical HCC tissues; its level was inversely correlated with multiple clinicopathological factors, such as tumor grade, tumor size, and Ki67 expression. Cox regression analysis of tumor samples revealed that BCCIP expression status was an independent prognostic factor for HCC patients’ poor survival. Our study also indicated that BCCIP shutdown reduces p21 expression and accelerates G1 to S progression of LO2 hepatocytes significantly. Moreover, there is an interaction between BCCIP and p53 in hepatic L02 cells, and the downregulation of p21 expression by BCCIP is in a p53-dependent way. These findings revealed that BCCIP may play a significant role for the determination of HCC progression through its role in regulating cell growth. Thus, our results suggest that BCCIP is of potential interest for prognostic marker and therapeutic target of HCC.