Prognostic and clinicopathological features of E-cadherin, α-catenin,β-catenin, γ-catenin and cyclin D1 expression in human esophageal squamous cell carcinoma

AIM: To investigate the expression of E-cadherin, α-catenin,β-catenin, γ-catenin and cyclin D1 in patients with esophageal squamous cell carcinoma (ESCC), and analyze their interrelationship with clinicopathological variables and their effects on prognosis. METHODS: Expression of E-cadherin, α-catenin, β-catenin, γ-catenin and cyclin D1 was determined by EnVision or SABC immunohistochemical technique in patients with ESCC consecutively, their correlation with clinical characteristics was evaluated and analyzed by univariate analysis. RESULTS：The reduced expression rate of E-cadherin, α-catenin, β-catenin and γ-catenin was 88.7%, 69.4%, 35.5% and 53.2%, respectively. Cyclin D1 positive expression ratewas 56.5%. Expression of γ-catenin was inversely correlated with the degree of tumor differentiation and lymph node metastasis (x^2=4.183 and x^2=5.035, respectively, P<0.05), whereas the expression of E-cadherin was correlated only with the degree of differentiation (x^2=5.769, P<0.05). Reduced expression of E-cadherin and γ-catenin was associated with poor differentiation of tumor, reduced expression of γ-catenin was also associated with lymph node metastasis. There obviously existed an inverse correlation between level of E-cadherin and γ-catenin protein and survival. The 3-year survival rates were 100% and 56% in E-cadherin preserved expression group and inreduced expression one and were 78% and 48% in γ-catenin preserved expression group and in reduced expression one, respectively. The differences were both statistically significant. Correlation analysis showed the expression level of α-catenin correlated with that of E-cadherin and β-catenin (P<0.05). CONCLUSION: The reduced expression of E-cadherin and γ-catenin, but not α-catenin, β-catenin and cyclin D1, implies more aggressive malignant behaviors of esophageal carcinoma cells and predicts the poor prognosis of patients.     

Expression of e-cadherin and β-catenin in human esophageal squamous cell carcinoma: relationships with prognosis

AIM: To elucidate the expression of E-cadherin and β-catenincorrelating with its clinical outcome in patients withesophageal squamous cell carcinoma (ESCC), by analyzingtheir interrelationship with clinicopathological variables andtheir effects on progress and prognosis.METHODS: Expression of E-cadherin and β-catenin wasdetermined by SP immunohistochemical technique inpatients with ESCC consecutively, their correlation withclinical characteristics was evaluated and analyzed bymultivariate analysis.RESULTS: The rate of expression of E-cadherin decreasedto 66.03 % (70/106) in ESCC and the protein level wasnegative correlated with histologic grade, tumor size, clinicalstaging, lymph node metastasis and venous invasion.Whereas the expression rate of β-catenin was reduced to69.8 % (74/106) and the level of protein expressioncorrelated only with histologic grade. There obviously existedinverse correlation between level of E-cadherin protein andsurvival, especially in .stage I, IIa, IIb (P=0.0033), Patientswith low-expressing tumors for β-catenin and non-expressingtumors for E-cadherin/β-catenin had lower survival periodthan those with normal-expressing ones (P=0.0501 andP=0.0080, respectively). Patients with diminished expressionof E-cadherin as grade Ⅱ or Ⅲ had shorter survival periodthan those with normally expressing and grade Ⅰ, nosignificance existed between grade I and grade Ⅱ or Ⅲwith respect to different status of E-cadherin expression.Furthermore, Correlation analysis showed level of E-cadherincorrelated with that of β-catenin (P=0.005). Cox proportionalhazards model analysis suggested downregulation of E-cadherin was an important factor indicating poor prognosis.CONCLUSION: As a probable independent prognosticfactor, it correlates with overall and disease free survivalperiod, expression of E-cadherin but not β-catenin maypredict prognosis in patients with ESCC.     

Expression of e-cadherin and β-catenin in human esophageal squamous cell carcinoma： relationships with prognosis

AIM: To elucidate the expression of E-cadherin and β-catenin correlating with its clinical outcome in patients with esophageal squamous cell carcinoma (ESCC), by analyzing their interrelationship with clinicopathological variables and their effects on progress and prognosis.METHODS: Expression of E-cadherin and β-catenin was determined by SP immunohistochemical technique in patients with ESCC consecutively, their correlation with clinical characteristics was evaluated and analyzed by multivariate analysis.RESULTS: The rate of expression of E-cadherin decreased to 66.03% (70/106) in ESCC and the protein level was negative correlated with histologic grade, tumor size, clinical staging, lymph node metastasis and venous invasion.Whereas the expression rate of β-catenin was reduced to 69.8% (74/106) and the level of protein expression correlated only with histologic grade. There obviously existed inverse correlation between level of E-cadherin protein and survival, especially in stage I, IIa, IIb (P=0.0033), Patients with low-expressing tumors for β-catenin and non-expressing tumors for E-cadherin/β-catenin had lower survival period than those with normal-expressing ones (P=0.0501 and P=0.0080, respectively). Patients with diminished expression of E-cadherin as grade II or III had shorter survival period than those with normally expressing and grade I, no significance existed between grade I and grade II or III with respect to different status of E-cadherin expression.Furthermore, Correlation analysis showed level of E-cadherin correlated with that of β-catenin (P=0.005). Cox proportionalhazards model analysis suggested downregulation of E-cadherin was an important factor indicating poor prognosis.CONCLUSION: As a probable independent prognosticfactor, it correlates with overall and disease free survival period, expression of E-cadherin but not β-catenin may predict prognosis in patients with ESCC.     

Role of the Na~+/K~+/2Cl~- cotransporter NKCC1 in cell cycle progression in human esophageal squamous cell carcinoma

AIM:To investigate the role of Na+/K+/2Cl-cotransporter 1(NKCC1)in the regulation of genes involved in cell cycle progression and the clinicopathological significance of its expression in esophageal squamous cell carcinoma(ESCC).METHODS:An immunohistochemical analysis was performed on 68 primary tumor samples obtained from ESCC patients that underwent esophagectomy.NKCC1expression in human ESCC cell lines was analyzed by Western blotting.Knockdown experiments were conducted using NKCC1 small interfering RNA,and the effects on cell cycle progression were analyzed.The gene expression profiles of cells were analyzed by microarray analysis.RESULTS:Immunohistochemical staining showed that NKCC1 was primarily found in the cytoplasm of carcinoma cells and that its expression was related to the histological degree of differentiation of SCC.NKCC1 was highly expressed in KYSE170 cells.Depletion of NKCC1in these cells inhibited cell proliferation via G2/M phase arrest.Microarray analysis identified 2527 genes with altered expression levels in NKCC1depleted KYSE170.Pathway analysis showed that the top-ranked canonical pathway was the G2/M DNA damage checkpoint regulation pathway,which involves MAD2L1,DTL,BLM,CDC20,BRCA1,and E2F5.CONCLUSION:These results suggest that the expression of NKCC1 in ESCC may affect the G2/M checkpoint and may be related to the degree of histological differentiation of SCCs.We have provided a deeper understanding of the role of NKCC1 as a mediator and/or a biomarker in ESCC.     

Effect of thioredoxin-interacting protein on Wnt/β-catenin signaling pathway and diabetic myocardial infarction

Objective:To explore the regulatory role of thioredoxin-interacting protein(TXNIP) in Wnt/β-catenin signaling pathway and therefore to elucidate its function in diabetic myocardial infarction.Methods:Diabetic myocardial infarction models were generated in mice.The expression levels of TXNIP and β-catenin and level of reactive oxygen species(ROS) were determined and compared with those in control group.Human umbilical vein endothelial cells were treated with high-eoncentration glucose and/or silencing TXNIP and/or H_2O_2.After 24 h,expression levels of TXNIP、β-catenin and its downstream protein Cyclin D1,and C-myc gene were determined by real-time PCR,Western blot and immunofluorescence method.The cell proliferation and ROS production capability in different groups were determined by methyl thiazolyl tetrazolium assay.Results:Compared with control group,hyperglycemia significantly up-regulated TXNIP expression and ROS level in the myocardium and endothelial cells of myocardial infarction area,whereas the β-catenin expression was down-regulated,and the difference was statistically significant(P0.05).In comparison with Human umbilical vein endothelial cells in the control group,high glucose level increased the levels of TXNIP expression and ROS level in cells,but reduced cell proliferation as well as migration capability and expression levels of β-catenin,Cyclin D1 and C-myc;the difference was statistically significant(P0.05).However,this trend can be partially reversed by silencing TXNIP.Conclusions:Diabetic myocardial ischemia could up-regulate levels of TXNIP expression and ROS production in endothelial cells of myocardial infarction area.The regulation effect of TXNIP on β-catenin was partially achieved by changing ROS levels.     

Inhibitory effect of caffeic acid phenethyl ester on the growth of SW480 colorectal tumor cells involvesβ-catenin associated signaling pathway down-regulation

AIM: To study the anti-tumor effect of caffeic acid phenethyl ester (CAPE) and the influence of CAPE onβ-catenin associated signaling pathway in SW480 colorectal cancer (CRC) cells. METHODS: SW480 cells were treated with CAPE at serial concentrations. The proliferative status of cells was measured by methabenzthiazuron (MTT) assay. Cell cycle and cell apoptosis were analyzed using flow cytometry (FCM). Western blotting assay was used to evaluate the protein level ofβ-catenin, c-myc and cyclinDl. p-catenin localization was determined by indirect immunofluorescence. RESULTS: CAPE displayed a strong inhibitory effect in a significant dose- and time-dependent manner on SW480 cell growth. FCM analysis showed that the ratio of G0 /G1 phase cells increased, S phase ratio decreased and apoptosis rate increased after SW480 cells were exposed to CAPE for 24 h. Pretreatment of SW480 cells with CAPE significantly suppressed p-catenin, c-myc and cyclinD1 protein expression. CAPE treatment was associated with decreased accumulation ofβ-catenin protein in nucleus and cytoplasm, and concurrently increased its accumulation on the surface of cell membrane. CONCLUSION: CAPE can inhibit SW480 cell proliferation by inducing cell cycle arrest and apoptosis. Decreased p-catenin and the associated signaling pathway target gene expression may mediate the anti-tumor effects of CAPE.     

Tumor suppressor function of ezrin-radixin-moesin-binding phosphoprotein-50 through β-catenin/E-cadher in pathway in human hepatocellular cancer

AIM:To determine the effect and molecular mechanism of ezrin-radixin-moesin-binding phosphoprotein-50(EBP50) in hepatocellular carcinoma(HCC).METHODS:Three human HCC cell lines,i.e.,SMMC7721,HepG2 and Hep3B,were used.We transfected the Pbk-CMV-HA-EBP50 plasmid into SMMC7721 cells with Lipofectamine 2000 to overexpress EBP50.Western blotting were performed to determine the effects of the plasmid on EBP50 expression and to detect the expression of β-catenin and E-cadherin before and after the transfection of the plasmid into SMMC7721 cells.In vitro cell proliferation was assessed with a Cell Counting Kit-8(CCK-8) assay.Cell cycle distribution was assessed with flow cytometry.Invasion and migration ability of before and after the transfection were determined with a transwell assay.Cell apoptosis was demonstrated with Annexin V-FITC.The effect of EBP50 overexpressing on tumor growth in vivo was performed with a xenograft tumor model in nude mice.RESULTS:The transfection efficiency was confirmed with Western blotting(1.36 ± 0.07 vs 0.81 ± 0.09,P < 0.01).The CCK8 assay demonstrated that the growth of cells overexpressing EBP50 was significantly lower than control cells(P < 0.01).Cell cycle distribution showed there was a G0/G1 cell cycle arrest in cells overexpressing EBP50(61.3% ± 3.1% vs 54.0% ± 2.4%,P < 0.05).The transwell assay showed that cell invasion and migration were significantly inhibited in cells overexpressing EBP50 compared with control cells(5.8 ± 0.8 vs 21.6 ± 1.3,P < 0.01).Annexin V-FITC revealed that apoptosis was significantly increased in cells overexpressing EBP50 compared with control cells(14.8% ± 2.7% vs 3.4% ± 1.3%,P < 0.05).The expression of β-catenin was downregulated and E-cadherin was upregulated in cells overexpressing EBP50 compared with control cells(0.28 ± 0.07 vs 0.56 ± 0.12,P < 0.05;0.55 ± 0.08 vs 0.39 ± 0.07,P < 0.05).In vivo tumor growth assay confirmed that up-regulation of EBP50 could obviously slow the growth of HCC derived from SMMC7721 cells(     

Interaction between cyclooxygenase-2,Snail,and E-cadherin in gastric cancer cells

AIM:To investigate the mechanisms of how cyclooxygenase-2(COX-2)regulates E-cadherin in gastric cancer cells.METHODS:COX-2 expression in human gastric cancer cell lines SGC-7901,BGC-823,MGC-803 and AGS were measured at the mRNA and protein level.COX-2 rich cell line SGC-7901 was chosen for subsequent experiments.siRNA mediated gene knockdown was used to investigate the impact of COX-2 on nuclear factor-κB (NF-κB),Snail,and E-cadherin in gastric cancer cells.Gene expression was determined by Western blot and real-time polymerase chain reaction.To analyze whether NF-κB inhibition could interrupt the modulatory effect of COX-2 or prostaglandin E2(PGE2)on E-cadherin,gastric cancer cells were treated with celecoxib or PGE2,in the presence of NF-κB specific siRNA.RESULTS:Highest expression level of COX-2 was found in SGC-7901 cells,both at mRNA and protein levels.siRNA mediated down-regulation of COX-2 led to a reduced expression of NF-κB and Snail,but an increased expression of E-cadherin in SGC-7901 cells.siRNA mediated down-regulation of NF-κB also led to a reduced expression of E-cadherin and Snail in SGC-7901 cells.However,COX-2 expression did not alter after cells were treated with NF-κB specific siRNA in SGC-7901 cells.Treatment of SGC-7901 cells with celecoxib led to a reduced expression of Snail but an increased expression of E-cadherin.In contrast,treatment of SGC-7901 cells with PGE2 led to an increased Snail and a decreased E-cadherin.However,siRNAmediated knockdown of NF-κB partially abolished the effect of celecoxib and PGE2 on the regulation of E-cadherin and Snail in SGC-7901 cells.CONCLUSION:COX-2 likely functions upstream of NF-κB and regulates the expression of E-cadherin via NF-κB/Snail signaling pathway in gastric cancer cells.     

N-cadherin knock-down decreases invasiveness of esophageal squamous cell carcinoma in vitro

AIM： To examine the expressions of N-cadherin and E-cadherin in specimens of 62 normal esophageal epithela, 31 adjacent atypical hyperplastic epithelia and 62 esophageal squamous cell carcinomas （ESCCs）, and to investigate the roles of N-cadherin in the invasiveness of ESCC cell line EC9706 transfected by N-cadherin shRNA.
METHODS： PV immunohistochemistry was used to detect the expression pattern of N-cadherin and E-cadherin in specimens of 62 normal esophageal epithelia, 31 adjacent atypical hyperplastic epithelia and 62 ESCCs. The invasiveness of ESCC line EC9706 was determined by transwell assay after EC9706 was transfected by N-cadherin shRNA.
RESULTS： The positive rotes of N-cadherin decreased in the carcinoma, adjacent atypical hyperplastic and normal esophageal tissues （75.8%, 61.3% and 29.0%, P 〈 0.05）, respectively, while those of E-cadherin increased （40.3%, 71.0% and 95.2%, P 〈 0.05）. The increased expression of N-cadherin and decreased expression of E-cadherin were related to invasion, differentiation, and lymph node metastasis （P 〈 0.05）. The expression level of N-cadherin decreased in the N-cadherin knocked down cells, and the invasiveness of those cells decreased significantly as well. The number of cells which crossed the basement membrane filter decreased from 123.40 ± 8.23 to 49.60 ±6.80 （P 〈 0.05）.
CONCLUSION： E-cadherin and N-cadherin expression is correlated with the invasion and aggravation of ESCC. The down-regulation of N-cadherin lowers the invasiveness of EC9706 cell line.     

MiR-19a-3p regulates the Forkhead box F2-mediated Wnt/β-catenin signaling pathway and affects the biological functions of colorectal cancer cells

BACKGROUND Colorectal cancer(CRC)is one of the most common malignancies worldwide.AIM To explore the expression of microRNA miR-19a-3p and Forkhead box F2(FOXF2)in patients with CRC and the relevant mechanisms.METHODS Sixty-two CRC patients admitted to the hospital were enrolled into the study group,and sixty healthy people from the same period were assigned to the control group.Elbow venous blood was sampled from the patients and healthy individuals,and blood serum was saved for later analysis.MiR-19a-3p mimics,miR-19a-3p inhibitor,miR-negative control,small interfering-FOXF2,and short hairpin-FOXF2 were transfected into HT29 and HCT116 cells.Then quantitative polymerase chain reaction was performed to quantify the expression of miR-19a-3p and FOXF2 in HT29 and HCT116 cells,and western blot(WB)analysis was conducted to evaluate the levels of FOXF2,glycogen synthase kinase 3 beta(GSK-3β),phosphorylated GSK-3β(p-GSK-3β),β-catenin,p-β-catenin,α-catenin,Ncadherin,E-cadherin,and vimentin.The MTT,Transwell,and wound healing assays were applied to analyze cell proliferation,invasion,and migration,respectively,and the dual luciferase reporter assay was used to determine the correlation of miR-19a-3p with FOXF2.RESULTS The patients showed high serum levels of miR-19a-3p and low levels of FOXF2,and the area under the curves of miR-19a-3p and FOXF2 were larger than 0.8.MiR-19a-3p and FOXF2 were related to sex,tumor size,age,tumor-nodemetastasis staging,lymph node metastasis,and differentiation of CRC patients.Silencing of miR-19a-3p and overexpression of FOXF2 suppressed the epithelialmesenchymal transition,invasion,migration,and proliferation of cells.WB analysis revealed that silencing of miR-19a-3p and FOXF2 overexpression significantly suppressed the expression of p-GSK-3β,β-catenin,N-cadherin,and vimentin;and increased the levels of GSK-3β,p-β-catenin,α-catenin,and Ecadherin.The dual luciferase reporter assay confirmed that there was a targeted correlation of miR-19a-3p with FOXF2.In addition,a rescue experiment revealed that there were no differences in cell proliferation,invasion,and migration in HT29 and HCT116 cells co-transfected with miR-19a-3p-mimics+sh-FOXF2 and miR-19a-3p-inhibitor+si-FOXF2 compared to the miR-negative control group.CONCLUSION Inhibiting miR-19a-3p expression can upregulate the FOXF2-mediated Wnt/β-catenin signaling pathway,thereby affecting the epithelial-mesenchymal transition,proliferation,invasion,and migration of cells.Thus,miR-19a-3p is likely to be a therapeutic target in CRC.     

Inhibition effect of miR-577 on hepatocellular carcinoma cell growth via targeting β-catenin

Objective:To investigate the expression and the regulation effect of cell growth of microRNA-577 in hepatocellular carcinoma(HCC).Methods:qRT-PCR was applied to detect the relative expression of miR-577 in 70 paired HCC and matched tumor adjacent tissues collecting from resection between March 2011 and March 2014.Pearson chi-square test was used to analyze the relationship between the miR-577 expression and clinical features.The miR-577 mimics were transfected into HepG2 cells:cell cycles were detected by flow cytometry,cell proliferation was measured by MTT assay and BrdU incorporation assay,and cell apoptosis was determined by flow cytometry and Caspase 3/7 activity analysis.The expressions ofβ-catenin were measured by immunohistochemistry.Spearman correlation analysis was used to analyze the relationship between miR-577 and p-catenin.qRT-PCR and westernblot were used to detect the expression of p-catenin in transfected HepG2 cells.Results:The relative expressions of miR-577 was significantly lower in HCC tissues compared to the matched normal tumor-adjacent tissues(P0.05).Low expression of miR-577 was significantly associated with large tumor size(≥5 cm,P0.05) and advanced tumor node metastasis stage(Ⅲ+Ⅳ,P0.05).Transfection of miR-577 mimics could inhibit repress cell proliferation,enhance cell apoptosis and block the cell cycles in G_1/G_1 phase(P0.05).miR-577 in HCC group had a significant negative correlation relationship with the expression of downstream target of β-catenin(P0.05).Both the mRNA and protein expression in HepG2 cells were down-regulated after transfection(P0.05).Conclusions:Low expression of miR-577 is related to the malignant clinicopathological features in HCC tissues,and miR-577 may suppress HCC growth through down-regulating p-catenin.     

Effect of caffeic acid phenethyl ester on proliferation and apoptosis of colorectal cancer cells in vitro

ABM: To study the effect of caffeic add phenethyl ester (CAPE) on proliferation, cell cycle, apoptosis and expression of β-catenin in cultured human colorectal cancer (CRC) cell line HCT116. METHODS: HCT116 cells were treated with CAPE at serial concentrations of 80,40,20,10,5,2.5 mg/L. The proliferative status of HCT116 cells was measured by using methaben-zthiazuron (MTT) assay. Cell cycle was analyzed by using flow cytometry (FCM) with propidium iodide (PI) labeling method. The rate of apoptosis was detected by using FCM with annexin V-FITC and PI double labeling method, β-catenin levels were determined by Western blotting, β-catenin localization in HCT116 was determined by indirect immunofluorescence. RESULTS: After HCT116 cells were exposed to CAPE (80, 40, 20, 10, 5, and 2.5 mg/L) for 24, 48, 72, 96 h, CAPE displayed a strong growth inhibitory effect in a dose- and time-dependent manner against HCT116 cells. FCM analysis showed that the ratio of G0/G1 phase cells increased, S phase ratio decreased and apoptosis rate increased after HCT116 cells were exposed to CAPE (10, 5, and 2.5 mg/L) for 24 h. CAPE treatment was associated with decreased cytoplasmic β-catenin, nuclear p-catenin and a concurrent increase in β-catenin protein expression at cell-cell junctions. CONCLUSION: CAPE could inhibit HCT116 cell proliferation and induce cell cycle arrest and apoptosis. Decreased β-catenin protein expression may mediate the anti-proliferative effects of CAPE.     

Expression of midkine and its clinical significance in esophageal squamous cell carcinoma

AIM: TO investigate the expression of midkine in esophageal squamous cell carcinoma (ESCC) and analyze its relationship with clinicopathological features. METHODS: RT-PCR and immunocytochemical staining were used to detect the expression of midkine mRNA and protein in EC109 cells, respectively. Then the expression of midkine in 66 cases of ESCC samples were detected by immunohistochemistry using monoclonal antibodies against human midkine. RESULTS: Midkine was expressed in EC109 cell by RT-PCR and immunocytochemistry. The immunoreactivity was detected in 56.1% (37/66) of the ESCC samples. The expression of midkine was found in cytoplasm of tumor cells. Notably, the intensity of midkine was stronger at the area abundant in vessels and the invading border of the tumors. Midkine was more intensely expressed in well differentiated tumors (76.9%) than in moderately and poorly differentiated tumors (43.1% and 41.2%, respectively) (P<0.05). There was no statistically significant correlation between midkine expression and gender, age, clinical stage, lymph node metastasis or survival in ESCC. CONCLUSION: Midkine is overexpressed in ESCC. It may play a role in tumor angiogenesis and invasion. The expression of midkine is correlated with tumor cell differentiation in ESCC. The more poorly tumor cells differentiate, the weaker midkine expresses.     

Relationship between p-catenin expression and epithelial cell proliferation in gastric mucosa with intestinal metaplasia

AIM: To investigate β-catenin expression in patients with intestinal metaplasia, and to look for a possible relationship between β-catenin expression and either epithelial proliferation values or Helicobacter pylori (H pylori) infection. METHODS: Twenty patients with complete type intestinal metaplasia were studied. β-Catenin expression and epithelial cell proliferation in antral mucosa were assessed using an immunohistochemical analysis. H pylori infection was detected by histology and a rapid urease test. RESULTS: Reduced β-catenin expression on the surface of metaplastic cells was detected in 13 (65%) out of 20 patients. Moreover, in eight (40%) patients intranuclear expression of β-catenin was found. When patients were analyzed according to H pylori infection, the prevalence of both β-catenin reduction at the cell surface and its intranuclear localization did not significantly differ between infected and uninfected patients. Cell proliferation was higher in patients with intranuclear β-catenin expression as compared to the remaining patients, although the difference failed to reach the statistical significance (36±8.9 vs27.2±11.4, P=0.06). On the contrary, a similar cell proliferation value was observed between patients with reduced expression of β-catenin on cell surface and those with a normal expression (28.1±11.8 vs26.1±8.8, P= 0.7). H pylori infection significantly increased cell proliferation (33.3±10.2% vs 24.6±7.4%, respectively, P=0.04). CONCLUSION: Both cell surface reduction and intranuclear accumulation of β-catenin were detected in intestinal metaplasia. The intranuclear localization of β-catenin increases cell proliferation. H pylori infection does not seem to play a direct role in β-catenin alterations, whilst it significantly increases cell proliferation.     

β-catenin up-regulates the expression of cyclinD1, c-myc and MMP-7 in human pancreatic cancer: Relationships with carcinogenesis and metastasis

AIM: To investigate whether abnormal expression of β-catenin in conjunction with overexpression of cyclinD1, c-myc and matrix metalloproteinase-7 (MMP-7) correlated with the carcinogenesis, metastasis and prognosis of pancreatic cancer, and to analyze the relationship of β-catenin expression with cyclinDl, c-myc and MMP-7 expression. METHODS: Using immunohistochemistry,we examined the expression of β-catenin, cyclinD1,c-myc and MMP-7 in 47 pancreatic adenocarcinoma tissues, 12 pancreatic intraepithelial neoplasia (PanIN) and 10 normal pancreases, respectively. Proliferation cell nuclear antigen was also tested as the index of proliferative activity of pancreatic cancer cells. RESULTS: In 10 cases of normal pancreatic tissues, epithelial cells showed equally strong membranous expression of β-catenin protein at the cell-cell boundaries, but the expression of cyclinDl, c-myc and MMP-7 was negative. The expression of β-catenin, cyclinD1, c-myc and MMP-7 in PanIN and pancreatic adenocarcinoma tissues had no significant difference [6/12 and 32/47 (68.1%), 6/12 and 35/47 (74.5%), 5/12 and 33/47 (70.2%), 7/12 and 30/47 (63.8%), respectively]. The abnormal expression of β-catenin was significantly correlated to metastasis and one-year survival rate of pancreatic cancer, but had no relation with size, differentiation and cell proliferation. The expression of cyclinD1 was correlated with cell proliferation and extent of differentiation, but not with size, metastasis and one-year survival rate of the pancreatic cancer. The expression of c-myc was not correlated with size, extent of differentiation, metastasis and 1-year survival rate, but closely with cell proliferation of pancreatic cancer. The overexpression of MMP-7 was significantly associated with metastasis and 1-year survival rate of pancreatic cancer,but not with size, extent of differentiation and cell proliferation.There was a highly significant positive association between abnormal expression of β-catenin and overexpression of cyclinD1, c-myc and MMP-7 not only in PanIN (r= 1.000, 0.845, 0.845), but also in pancreatic cancer (r= 0.437, 0.452, 0.435). CONCLUSION: The abnormal expression of β-catenin plays a key role in the carcinogenesis and progression of human pancreatic carcinoma by up-regulating the expression of cyclinDl, c-myc and MMP-7, resulting in the degradation of extracellular matrix and uncontrolled cell proliferation and differentiation,β-catenin abnormal expression and MMP-7 overexpression may be considered as two useful markers for determining metastasis and prognosis of human pancreatic cancer.