Epigenetic inactivation of VGF associated with Urothelial Cell Carcinoma and its potential as a non-invasive biomarker using urine.
BACKGROUND
To identify new epigenetic markers and further characterize Urothelial Cell Carcinoma (UCC), we tested the promoter methylation (PM) status of 19 genes previously identified as cancer specific methylated genes in other solid tumors.


METHODS
We used bisulfite sequencing, methylation specific PCR and quantitative methylation specific PCR (QMSP) to test the PM status of 19 genes in urothelial cancer cell lines.


RESULTS
Among the 19 genes tested, VGF was found to be completely methylated in several UCC cell lines. VGF QMSP analysis showed that methylation values of almost all the primary 19 UCC tissues were higher than the paired normal tissues (P=0.009). In another cohort, 12/35 (34.3%) of low grade UCC cases displayed VGF methylation. As a biomarker for non-invasive detection of UCC, VGF showed a significantly higher frequency of methylation in urine from UCC cases (8/20) compared to controls (1/20) (P=0.020). After treatment of cell lines with 5-Aza-2'-deoxycytidine, VGF was robustly re-expressed. Forced expression of VGF in bladder cancer cell lines inhibited cell growth.


CONCLUSIONS
Selection of candidates from genome-wide screening approach in other solid tumors successfully identified UCC specific methylated genes.
Department of Otolaryngology-Head and Neck Surgery, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.
Masamichi
M
Hayashi
Heike
H
Bernert
Luciane Tsukamoto
LT
Kagohara
Leonel
L
Maldonado
Mariana
M
Brait
Mark
M
Schoenberg
Trinity
T
Bivalacqua
George J
GJ
Netto
Wayne
W
Koch
David
D
Sidransky
Mohammad O
MO
Hoque
D014408:Biomarkers, Tumor / Q000235:genetics* / Q000652:urine*; D002295:Carcinoma, Transitional Cell / Q000235:genetics* / Q000652:urine; D045744:Cell Line, Tumor; D019175:DNA Methylation; D044127:Epigenesis, Genetic; D015972:Gene Expression Regulation, Neoplastic; D020868:Gene Silencing; D006801:Humans; D009414:Nerve Growth Factors / Q000235:genetics* / Q000652:urine; D011401:Promoter Regions, Genetic / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction; D020133:Reverse Transcriptase Polymerase Chain Reaction; D001749:Urinary Bladder Neoplasms / Q000235:genetics* / Q000652:urine
D014408:Biomarkers, Tumor; D009414:Nerve Growth Factors; C510637:VGF protein, human