Infrequently methylated event at sites -181 to -9 within the 5' CpG island of E-cadherin in non-small cell lung cancer.
Epigenetic silencing of E-cadherin via aberrant methylation has been investigated in various human tumors, whereas evidence for elucidating mechanism underlying reduction of E-cadherin mRNA remains unclear in non-small cell lung cancer (NSCLC). The authors previously found that reduction of E-cadherin mRNA or protein expression has been frequently observed in NSCLC. In this study, the authors explore the contribution of E-cadherin methylation to the development and progression of NSCLC. The authors directly performed the bisulfite DNA sequencing to examine CpG methylation within the 5' CpG island of E-cadherin in 35 tumor and paired normal tissue specimens from patients with primary NSCLC. Then, the authors measured the level of E-cadherin mRNA by real-time quantitative polymerase chain reaction (PCR) analysis. Despite of reduction in E-cadherin mRNA by 65.7% (23/35) and presence of methylation by 28.6% (10/35) in tumors, the authors found no association of reduction of E-cadherin mRNA level with methylation of 19 sites from -181 to -9 bp located upstream from the translation start of E-cadherin in NSCLC. In conclusion, the authors provide no evidence for the presence of aberrant methylation sites of E-cadherin in tumors from patients with NSCLC, which can explain decrease of E-cadherin mRNA. Decrease in E-cadherin mRNA may be regulated by methylation-independent pathways in NSCLC.
Laboratory of Medical Genetics, School of Basic Medicine and Biological Sciences, Medical College of Soochow University, Suzhou, PR China.
Reng-Yun
RY
Liu
Zhe
Z
Lei
Wenwen
W
Li
Linyan
L
Xu
Zeyi
Z
Liu
Xiao-Feng
XF
Chen
Jun
J
Zhao
Hong-Tao
HT
Zhang
D000368:Aged; D001483:Base Sequence; D015820:Cadherins / Q000235:genetics*; D002289:Carcinoma, Non-Small-Cell Lung / Q000235:genetics* / Q000473:pathology; D016022:Case-Control Studies; D045744:Cell Line, Tumor; D018899:CpG Islands; D019175:DNA Methylation; D017931:DNA Primers / Q000235:genetics; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000235:genetics* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D012334:RNA, Neoplasm / Q000235:genetics / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction
D015820:Cadherins; D017931:DNA Primers; D012333:RNA, Messenger; D012334:RNA, Neoplasm