Signiifcance Expression Of TMPRSS2-ERG Fusion Gene,ERG Protein And Engrailed-2Protein In Prostate Cancer

【Objective】To evaluate the expression of TMPRSS2-ERG (T-E) fusion gene by fluorescencein situ hybridization (FISH) and level of ERG protein and Engrailed-2(EN2) proteinby immunohistochemistry (IHC).To investigate their diagnosis effect in prostatebiopsy specimens and the correlation with prognosis in prostate cancer.【Methods】1.The expression of T-E fusion gene was detected by FISH in145prostate cancerbiopsy specimens.50biopsy specimens from normal prostate were selected as controlat random.2.The lever of ERG protein and EN2protein were detected by EliVision? plusimmunohistochemical in the same specimens as part1.【Results】1.Of145prostate cancer specimen,37(25.5%) showed ERG rearrangement of T-Efusion gene by FISH. There was no signiifcant association between T-E fusion geneand age, preoperative serum PSA levels, Gleason sum, metastasis or survival time(P>0.05).2.Over-expression ratio of ERG protein was24.8%(36/145)，and had signiifcancecorrelation with preoperative serum PSA levels(P<0.05),while not with age, Gleasonsum, metastasis or survival time.86.1%(31/36) of ERG protein over-expression wasobserved the fusion of T-E gene. Relatively high consistency results were detectedbetween ERG protein IHC3+(20/145)and FISH (100.0%).EN2proteinoverexpression ratio of prostate cancer and were87.6%(127/145) and71.0%(103/145). The disparation between prostate cancer and peripheral normal prostategland has statistics signiifcant,while EN2protein expression of cancer IHC2+ (32.4%vsl9.3%) and IHC3+(29.7%vsl.4%) were both higher than that of peripheralnormal prostate gland (X2=54.093，P=0.000).The lever of EN2protein has nosigniifcant association with age, preoperative serum PSA levels, Gleason sum,metastasis or survival time (P>0.05). The specimen proned to exist higher expressionextent of EN2protein when with the occurrence of T-E fusion gene (P>0.05)，but hadno association with the expression of ERG protein.[Conclusions]T-E fusion gene and ERG protein could be used as a speciifcity marker inprostate cancer,while their abnormal expression occurred in prostate cancer,but not innormal prostate gland. There was higher concordance between ERG protein detectedby IHC and T-E fusion gene detected by FISH.ERG protein may provide asimple，exact and cheap way to evaluate the occurrence of T-E fusion gene.EN2protein existed higher expression in prostate cancer than peripheral normal prostategland was considered as a potential marker in diagnosis of prostate cancer. Theintensity of EN2protein expression was correlated with T-E fusion gene，but not withERG protein.