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Objective To study the expression of osteopontin (OPN) in pancreatic cancer and to determine its prognostic significance.Methods Studies which evaluated the relationship between the expression of OPN and pancreatic cancer published up to May 2018 were found by searching the electronic databases which included the PubMed,Embase,Cochrane Library,CNKI,Wanfang and VIP.The RevMan 5.3 was used to analyze the data in this meta-analysis by determining the odds ratios (ORs) and their 95％ confidence intervals (CIs).Results Using our predetermined selection criteria,this meta-analysis included 13 studies,with 1073 cases of pancreatic cancer tissues in the case group and 346 cases of normal tissues in the control group.The results indicated OPN was over expressed in pancreatic cancers (OR =8.13,95％ CI:6.00 ～ 11.02;P ＜ 0.05).The differences in the expressions of OPN between the well differentiation group and the moderate-poor differentiation group (OR =0.37,95％ CI:O.25 ～ 0.57;P ＜ 0.05),between the clinical stage Ⅰ-Ⅱ group and the clinical stage Ⅲ-Ⅳ group (OR =0.23,95 ％ CI:0.14 ～ 0.38;P ＜0.05),and between the lymph node metastasis group and the no lymph node metastasis group (OR =3.77,95％ CI:1.99 ～ 7.13;P ＜ 0.05) were significant.The expressions of OPN did not correlate with gender,age and location of pancreatic cancer.Conclusions Current evidence indicated that OPN was significantly correlated with pancreatic cancer and its clinicopathological features.OPN could be used as an effective diagnostic and survival evaluation marker.
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Background:Vitamin D receptor( VDR)is a member of the steroid hormone receptor superfamily,which plays roles in various biological processes including cell proliferation,differentiation,apoptosis and immune responses,and is low expressed in many malignant tumors. Aims:To evaluate the expression and regulation mechanism of VDR in colorectal cancer. Methods:A total of 30 patients with colorectal cancer admitted from February 2010 to December 2012 at Ren Ji Hospital,School of Medicine,Shanghai Jiao Tong University were enrolled. Expression of VDR in cancerous tissue and para-cancer noncancerous tissue was determined by immunohistochemistry. Clinical data of 224 patients with colorectal cancer were collected from Gene Expression Omnibus( GEO)for analyzing the correlation between VDR expression in cancerous tissue and clinicopathological characteristics as well as survival time. Expression of VDR in human colon cancer cell lines HCT116 and SW620 transfected with enhancer of zeste homolog 2( EZH2 )-siRNA or treated with 5-azacytidine (5-AZA)was determined by real-time PCR,and methylation level of VDR promoter was determined by methylation-specific PCR( MSP). Results:Positivity rate of VDR was significantly lower in colorectal cancer tissue than that in para-cancer noncancerous tissue( 26. 7% vs. 70. 0%,P < 0. 001 ). Expression of VDR was negatively correlated with histological staging,distant metastasis,vascular metastasis and lymph node metastasis of colorectal cancer(P<0. 05). Survival time was significantly longer in patients with high expression of VDR than patients with low expression of VDR (P=0. 032). Compared with cells transfected with control-siRNA,expression of EZH2 mRNA and methylation level of VDR promoter in HCT116 and SW620 cells transfected with EZH2-siRNA were significantly decreased(P<0. 05),and expression of VDR mRNA was significantly increased(P<0. 05). Compared with negative control group,methylation level of VDR promoter in HCT116 and SW620 cells treated with 5-AZA was significantly decreased(P<0. 05),and expression of VDR mRNA was significantly increased(P<0. 05). Conclusions:Expression of VDR in colorectal cancer is down-regulated and positively correlated with a favourable prognosis. Transcriptional repression of VDR in colorectal cancer is co-regulated by histone methylation and DNA methylation.
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Objective To investigate whether EZH2 participates in the process of authphagy and its regulatory mechanism in CRC (colorectal cancer) .Methods ZEB1 ,EZH2 and PTEN expression were measured by Western blot and immunohistochemistry respectively .ZEB1 ,EZH2 and PTEN mRNA level were measured by real-time PCR .Electron microscopy was introduced to validate the existence of autophagy .Results Knockdown of EZH2 induced the formation of autophagosome in colorectal cancer cell lines , which was evident on electron microscopy .Furthermore ,Western Blot and real-time PCR data showed that ZEB1 and EZH2 may regulate the expression of PTEN ,which played a vital role in autophagy .Moreover ,downregulation of ZEB1 significantly reduced the expression of EZH2 .An inverse correlation between the expression of EZH2 and ZEB1 ,and the expression of PTEN was also revealed in CRC tissues ,when compared with normal tissue in patients .Conclusion The impact of EZH2 on autophagy via PTEN during CRC carcinogenesis is revealed .At the same time ,EZH2 expression may be regulated by ZEB1 in colorectal cancer .