Down-regulation of HCP5 inhibits cell proliferation, migration, and invasion through regulating EPHA7 by competitively binding miR-101 in osteosarcoma

Patients with osteosarcoma (OS) usually have poor overall survival because of frequent metastasis. Long non-coding RNAs (lncRNAs) have been reported to be associated with tumorigenesis and metastasis. In this study, we investigated the expression and roles of lncRNA human histocompatibility leukocyte antigen (HLA) complex P5 (HCP5) in OS, aiming to provide a novel molecular mechanism for OS. HCP5 was up-regulated both in OS tissues and cell lines and high expression of HCP5 was associated to low survival in OS patients. Down-regulation of HCP5 inhibited cell proliferation, migration, and invasion, suggesting its carcinogenic role in OS. miR-101 was targeted by HCP5 and its expression was decreased in OS. The inhibitor of miR-101 reversed the impact of HCP5 down-regulation on cell proliferation, apoptosis, and metastasis in OS. Ephrin receptor 7 (EPHA7) was proved to be a target of miR-101 and had ability to recover the effects of miR-101 inhibitor in OS. In conclusion, lncRNA HCP5 knockdown suppressed cell proliferation, migration, and invasion, and induced apoptosis through depleting the expression of EPHA7 by binding to miR-101, providing a potential therapeutic strategy of HCP5 in OS.

Expression of ephA7 in small cell lung cancer and its clinical significance / 肿瘤

Objective: To explore the expression of Ephrin receptor A7 (EphA7) in the patients with small cell lung cancer (SCLC) and its clinical significance. Methods: The expression of EphA7 mRNA in SCLC cell lines and tissues was analyzed by the Cancer Cell Line Encyclopedia (CCLE) and Oncomine databases, respectively. Seventy-three paraffin-embedded lung cancer specimens and six adjacent normal lung tissue samples from SCLC patients who underwent lobectomy or pneumonectomy resection in Tianjin Medical University Affiliated Cancer Hospital and Institution from January 2011 to December 2014 were collected. The expression of EphA7 protein was assessed by immunohistochemistry. The relationship between the expression of EphA7 protein and other clinicopathological factors was analyzed by x2 test. Kaplan-Meier survival curve and COX proportional hazard model were used to analyze the relationship between these clinicopathological parameters (including EphA7 expression) and the prognosis of SCLC patients. Results: The expression of EphA7 mRNA in SCLC cell lines was the highest among the 1 457 cell lines included in CCLE database. Three datasets of EphA7 mRNA expression in SCLC tissues were obtained from the Oncomine database. Compared with the normal lung tissues and non-small cell lung cancer, the expression level of EphA7 mRNA was relatively higher in SCLC tissues. The positive expression rate of EphA7 protein reached 72.6% (53/73) in the 73 patients with SCLC. The expression of EphA7 protein was significantly associated with lymph node metastasis and TNM stage (both P < 0.05). After adjusting other factors, it was found that the positive expression of EphA7 protein was an independent prognostic factor for the overall survival (OS) of SCLC patients [hazard ratio (HR) = 2.369, 95% confidence interval (CI): 1.075-5.219, P < 0.05], while TNM stage was an independent prognostic factor for both OS (HR = 2.273, 95% CI: 1.252-4.124, P < 0.05) and progression-free survival (PFS) (HR = 1.898, 95% CI: 1.088-3.312, P < 0.05) of SCLC patients, respectively. Conclusion: EphA7 mRNA and protein are highly expressed in SCLC tissues. The expression of EphA7 protein and TNM stage may be independent factors for the prognosis of SCLC patients.

The progression on tyrosine kinase receptor EphA7 in tumor / 实用肿瘤学杂志

EphA7 is one of the most important members of the Eph family .It is a key regulatory factor of cell adhesion and repulsion ,it also contributes to establish men ,maintain ance and tissue remodeling in cell mor-phology .In recent years ,its function in tumors has been revealed gradually .It plays a variety of roles in different tumors.The overexpression of EphA7 can be detected in acute leukemia ,glioblastomamultiforme,lung cancer and hepatic carcinoma ,which suggests EphA 7 may be involved in the development of these tumors .While in colon cancer,prostate cancer,follicular lymphoma and gastric cancer ,a significant reduction of EphA7 expression with promoter hypermethylation is discovered ,which suggests EphA 7 play a tumor suppressor role in these tumors .E-ven though the function of EphA 7 is still under exploration , EphA7 and tumor development are inextricably linked,it may have roles in the pathogenesis and development of these carcinomas .

RNA interference targeting EphA7 inhibits growth of SMMC-7721 cell xenograft in nude mice / 中华肝胆外科杂志

Objective To investigate the effects of RNA interference targeting EphA7 gene on the growth of SMMC-7721 cell xenograft in nude mice.Methods Recombinant plasmid of EphA7 gene-targeting siRNA was transfected into hepatic cancer SMMC-7721 cells by LipofectamineTM2000,comparing with the empty vector transfected group,untransfected group and control group.The nude mice tumor model was established by subcutaneous injection of hepatic cancer cells in the left upper limb of the mice.Control group was injected with PBS as blank.Real-time PCR,immunohistochemistry and Western blot were employed to detect the mRNA and protein expressions of EphA7 in tumor tissues.The tumor formation time,tumor mass and weight of tumor were also considered in the analysis.Results About 9 ～ 12 days after the injection of tumor cells,the xenograft tumor formation can be observed around the injection site except the control group.35 days after tumor formation,there were obvious decreases in the tumor growth rate,tumor mass,as well as tumor weight in transfected group,comparing with empty vector transfected group and untransfected group (P ＜0.05).Transfection of RNA interference can inhibit the growth of xenograft tumor by 55％.Immunohistochemistry tests showed that there were less cells with positive staining of EPHA7 protein in transfected group,and the staining was lighter as pale yellow,in contrast with the untransfected group and the empty vector transfected group.Real-time PCR and Western blot revealed that the expression of EphA7 mRNA and EPHA7 protein of transfected group were significantly lower than those of untransfected group and empty vector trausfected group with statistically significance (P ＜ 0.05).Conclusion Silencing EphA7 gene with RNA interference can effectively inhibit the growth of SMMC-7721 cell in nude mice,which is expected to become a new target for gene therapy of hepatic cancer.

The expression and significance of EphA7 in pancreatic carcinoma / 中华胰腺病杂志

Objective To investigate the relationship between EphA7 protein and carcinogenesis and development of pancreatic cancer by detecting the expression of EphA7 protein in pancreatic cancer tissues. Methods The expression of EphA7 in 10 cases of normal pancreatic tissue, 51 cases of pancreatic cancer and its adjacent tissues were detected with immunohistechemieal methods and the relationship between EphA7 and pathologic features of pancreatic cancer were analyzed. Results The rate of expression of EphA7 protein in normal pancreatic tissue was 10% (1/10), 47.1% (24/51) in adjacent pancreatic cancer tissues, 94.1% (48/51) in pancreatic cancer tissues. There were significant difference among the three groups (P <0.05). There was no significant correlation between the expression of EphA7 protein and the age, sex, tumor location, tumor size in patients with pancreatic cancer (P > 0.05). However there was significant correlation between the expression of EphA7 protein and the degree of differentiation, clinical staging, lymph node metastasis, or distant metastasis (P < 0.05). Conclusions The abnormally high expression of EphA7 may be relevant with the occurrence and development of the pancreatic cancer.

Down-regulation of EphA7 by aberrant methylation in colorectal cancer / 医学研究生学报

Objective:Ephs have been found to be over-expressed in numerous human tumors,and relate to the development and prognosis of cancers.The expression of EphA7 in colon cancer cell lines and primary colorectal cancers was detected.The role of EphA7 in the development of colorectal cancer was investigated. Methods:Quantitative reverse transcription-polymerase chain reaction was used to detect the expression of EphA7.Methylation specific PCR and bisulfite sequencing were used to examine the methylation status of EphA7.pEGFP-EphA7 plasmid was constructed and was transfected into HCT116 which lost the expression of EphA7.Gene chip was analyzed for the expression of genes between transfectant and mock cell. Results:Down-regulation of EphA7 was observed in cell lines of primary colorectal cancers,and the evidence of aberrant methylation was found in CpG island of EphA7 promoter.The methylation status of EphA7 gene was related to sex,differentiation and location of colorectal cancers.Some genes were up or down regulated in pEGFP-EphA7 transfectant. Conclusion: EphA7 gene may be involved in the carcinogenesis of colorectal cancer.The hypermethylation of CpG island is an important mechanism leading to the down regulation of EphA7 in colorectal cancer.

Expression of receptor tyrosine kinase EphA7 in gastric carcinoma and its clinical significances / 医学研究生学报

Objective:Eph is the largest member of the family of receptor tyrosine kinases (RTK). Hypermethylation of CpG island is an important mechanism leading to down-regulation of EphA7 in gastric cancer. The objective of this study is to investigate the expression level of EphA7 in gastric carcinoma and its roles in the development,progression and prognosis of gastric carcinoma. Methods:The expression level of EphA7 transcript in gastric carcinoma specimens and normal mucosa tissues was detected using real-time RT-PCR. Results:The expression level of EphA7 in gastric carcinoma was divided into three groups according to the expression rate in gastric cancer tissue and matched normal mucosa. Statistics analysis showed that the expression of EphA7 is significantly related to age and stage. Overexpression of EphA7 has a tendency to relate to metastasis. Conclusion:EphA7 is differentially expressed in gastric carcinoma specimens. Overexpression of EphA7 may play a role in the development and progress of gastric carcinoma.

Expression of EphA7 protein in gastric carcinoma and its clinicopathological significance / 医学研究生学报

Objective: To investigate EphA7 protein expression of gastric carcinoma cells and its clinicopathological parameters.Methods: The expression level of EphA7 protein in gastric carcinoma and normal mucosa was detected using immunohistochemical staining.Results: The overexpression of EphA7 protein in gastric carcinoma was significantly related to age(P=0.016) and stage(P =0.033).Conclusion: EphA7 was differentially expressed in gastric carcinoma cells.