已发表论文

通过多梳组蛋白显示上皮性卵巢癌复发的肿瘤异质性

 

Authors Gui T, Bai HM, Zeng JF, Zhong ZJ, Cao DY, Cui QC, Chen J, Yang JX, Shen K

Published Date September 2014 Volume 2014:7 Pages 1705—1716

DOI http://dx.doi.org/10.2147/OTT.S67570

Received 11 May 2014, Accepted 12 July 2014, Published 25 September 2014

Purpose: To investigate tumor heterogeneity in the recurrence of epithelial ovarian cancer demonstrated by polycomb group (PcG) proteins.
Methods: Tissue microarrays containing matched primary and recurrent ovarian tumors from the same patients were constructed for detection of PcG protein expression. Survival analyses of clinicopathological parameters and expression of PcG proteins were performed on progression-free survival (PFS) and overall survival (OS) of patients. Genetic and epigenetic heterogeneity was explored in aspects of gene copy number and microRNA (miRNA) profiling.
Results: PcG proteins were heterogeneously expressed in primary versus recurrent tumors (<0.05). In univariate survival analysis of the ovarian carcinoma cohorts, a significant association of intensive expression of BMI1 and EZH2 in first-onset lymph node metastases with shortened PFS was demonstrated (=0.010, =0.019); and a significant association of intensive expression of BMI1 and EZH2 in recurrent tumors with shortened OS was demonstrated (=0.042, =0.047). Importantly, BMI1 and EZH2 expression provided significant independent prognostic parameters in multivariate analyses (<0.05). Gene amplification did not always coincide with PcG protein expression. Eight miRNAs were found to be downregulated in recurrent tumors, among which miR-298 might indirectly regulate the expression of EZH2 through transcription factor ILF3.
Conclusion: Tumor heterogeneity exists in the recurrence of epithelial ovarian cancer, manifested by PcG protein expression and underlying genetic and epigenetic alterations. Intensive expression of BMI1 and EZH2 are predictors of earlier relapse and shorter OS, independent of grade and chemotherapy sensitivity. EZH2 and miR-298 have great potential to be new targets for treatment of recurrent ovarian cancer.
Keywords: PcG protein, miRNA