RRC ID 43135
Author Akahira J, Suzuki F, Suzuki T, Miura I, Kamogawa N, Miki Y, Ito K, Yaegashi N, Sasano H.
Title Decreased expression of RIZ1 and its clinicopathological significance in epithelial ovarian carcinoma: correlation with epigenetic inactivation by aberrant DNA methylation.
Journal Pathol Int
Abstract The retinoblastoma protein-interacting zinc finger gene (RIZ1) is considered a tumor suppressor gene. The purpose of the present study was to examine the expression of RIZ1 and evaluate its clinicopathological significance in ovarian carcinoma. Immunohistochemistry and quantitative reverse transcription-polymerase chain reaction (RT-PCR) was performed for RIZ1 and its clinicopathological significance was examined. DNA methylation status of RIZ1 was also studied. All (6/6) of the normal, 5/9 of benign, and 4/9 of borderline tissues were positive for RIZ1 protein. In ovarian cancer tissues 32.9% (54/164) were positive for RIZ1. Decreased expression of RIZ1 was significantly correlated with histological subtypes (P < 0.0001), high tumor grade (P = 0.0153) and advanced clinical stage (P = 0.0345), and high Ki67 index (P = 0.0117) but was not associated with the overall prognoses of the patients (P = 0.519). The presence of methylated band was detected in 2/9 cell lines, and 5/69 ovarian cancer tissues. Median values of relative RIZ1 expression in cell lines with methylation were significantly lower than those without methylation (P = 0.0404), and treatment of 5-aza-2'deoxycitidine resulted in demethylation and re-expression of RIZ1. Reduced expression of RIZ1 may play an important role in the pathogenesis and/or development of epithelial ovarian carcinoma, and is considered to be caused in part by aberrant DNA methylation.
Volume 57(11)
Pages 725-33
Published 2007-11-1
DOI 10.1111/j.1440-1827.2007.02169.x
PMID 17922684
MeSH Carcinoma / genetics* Carcinoma / metabolism* Carcinoma / pathology Cell Line, Tumor DNA Methylation DNA-Binding Proteins / genetics* DNA-Binding Proteins / metabolism* Epigenesis, Genetic Female Histone-Lysine N-Methyltransferase Humans Immunohistochemistry Middle Aged Neoplasm Staging Nuclear Proteins / genetics* Nuclear Proteins / metabolism* Ovarian Neoplasms / genetics* Ovarian Neoplasms / metabolism* Ovarian Neoplasms / pathology Promoter Regions, Genetic / genetics Reverse Transcriptase Polymerase Chain Reaction Transcription Factors / genetics* Transcription Factors / metabolism*
IF 2.11
Times Cited 11
Human and Animal Cells