1.The Function And Potential Mechanism Of ZNF471 In Esophageal Squamous Cell Carcinoma 2.Prognostic Significance Of Interferon Regulating Factor 4 In Esophageal Squamous Cell Carcinoma

PART ? THE FUNCTION AND POTENTIAL MECHANISM OF ZNF471 IN ESOPHAGEAL SQUAMOUS CELL CARCINOMAObjective: One study reported ZNF471(Zinc finger protein 471)as a KRAB-ZFP epigenetically inactivated in gastric carcinoma due to frequent promoter CpG methylation.However,its role of ZNF471 in esophageal squamous cell carcinoma(ESCC)is still elusive.Thus,we studied the biological functions and mechanism of ZNF471 in ESCC.Methods: Semi-quantitative reverse transcription polymerase chain reaction(RT-PCR)was carried out to detect ZNF471 expression in human normal tissues and ESCC cell lines.Real-time quantitative PCR(qPCR)were used to characterize its expression in ESCC and paired adjacent non-cancer tissues.Furthermore,its methylation status in ESCC cell lines and ESCC tissue samples was detected by methylation-specific PCR(MSP).CCK-8,colony formation,transwell assay,wound healing,flow cytometry and in vivo assays were performed in ZNF471-transfected and vector-transfected ESCC cell lines(KYSE150 and KYSE410)to study itsdifferent functional effects.Meanwhile,CCK-8,transwell assay and flow cytometry were performed using si-ZNF471 transfected and si-NC transfected KYSE270 to study its functional effects.RNA-Seq in KYSE410 cell was performed to identify differentially expressed genes regulated by ZNF471 in ESCC.Q-PCR,western blot,bioinformatics analysis,dual-luciferase reporter assay and ChIP assay were further analyzed to explore the effect on MAPK10/caspase8 signaling by ZNF471 in ESCC.Results: ZNF471 expression was silenced in ESCC cell lines due to aberrant promoter methylation.In addition,the majority of ESCC tissues had a lower level of ZNF471,while the adjacent non-tumor tissues showed a higher ZNF471 level.Moreover,ZNF471 methylation was detected in62.6% ESCC tissue samples but only 24.7% paired non-tumor adjacent tissue samples.Restoration of ZNF471 expression in silenced ESCC cells suppressed cell proliferation,arrested cell cycle,induced tumor cell apoptosis and suppressed cell migration and invasion.Knock down of ZNF471 expression in KYSE270 promoted cell proliferation,migration and invasion.Importantly,ZNF471 activated MAPK10/caspase8 signaling and the downstream target genes expression likely through directly binding to MAPK10 promoter.Conclusion: To sum up,our findings suggested that ZNF471 was downregulated in ESCC,and could act as a tumor suppressor gene inhibiting ESCC pathogenesis through activating MAPK10/caspase8 signaling pathway.PART ? PROGNOSTIC SIGNIFICANCE OF INTERFERON REGULATING FACTOR 4 IN ESOPHAGEAL SQUAMOUS CELL CARCINOMAObjective: Aberrant expression of interferon regulatory factor 4(IRF4)has been reported in several hematologic malignancies.However,the prognostic significance of IRF4 expression in esophageal squamous cell carcinoma(ESCC)remains unknown.Methods: IRF4 protein expression in ESCC tumor specimens was determined by immunohistochemistry.The correlation of IRF4 expression with clinico-pathological features was assessed from a cohort of 100 patients with primary ESCC.Kaplan-Meier and Cox proportional regression analyses were used to evaluate the association between IRF4 expression and patient survival.Results: A Kaplan-Meier analysis indicated that patients with high IRF4 expression had a significantly longer overall survival rate than those with low IRF4 expression(p=0.0006).Furthermore,multi-variate analyses revealed that IRF4 protein expression is an independent prognostic indicator for ESCC patients.Conclusion: Our results suggest that increased IRF4 protein expression correlates with improved outcome in ESCC.IRF4 may therefore represent a promising prognostic biomarker and potential immuno-therapeutic target for patients with ESCC.