Methylation-associated silencing of the tissue inhibitor of metalloproteinase-3 gene suggest a suppressor role in kidney, brain, and other human cancers.
Tissue inhibitor of metalloproteinase-3 (TIMP-3) antagonizes matrix metalloproteinase activity and can suppress tumor growth, angiogenesis, invasion, and metastasis. Loss of TIMP-3 has been related to the acquisition of tumorigenesis. Herein, we show that TIMP-3 is silenced in association with aberrant promoter-region methylation in cell lines derived from human cancers. TIMP-3 expression was restored after 5-aza-2'deoxycytidine-mediated demethylation of the TIMP-3 proximal promoter region. Genomic bisulfite sequencing revealed that TIMP-3 silencing was related to the overall density of methylation and that discrete regions within the TIMP-3 CpG island may be important for the silencing of this gene. Aberrant methylation of TIMP-3 occurred in primary cancers of the kidney, brain, colon, breast, and lung, but not in any of 41 normal tissue samples. The most frequent TIMP-3 methylation was found in renal cancers, which originate in the tissue that normally expresses the highest TIMP-3 levels. This methylation correlated with a lack of detectable TIMP-3 protein in these tumors. Together, these data show that methylation-associated inactivation of TIMP-3 is frequent in many human tumors.
The Johns Hopkins Oncology Center, The Graduate Program in Cellular and Molecular Medicine, The Johns Hopkins University School of Medicine, Baltimore, Maryland 21231, USA.
K E
KE
Bachman
J G
JG
Herman
P G
PG
Corn
A
A
Merlo
J F
JF
Costello
W K
WK
Cavenee
S B
SB
Baylin
J R
JR
Graff
D001374:Azacitidine / Q000031:analogs & derivatives / Q000494:pharmacology; D001932:Brain Neoplasms / Q000235:genetics*; D018899:CpG Islands; D019175:DNA Methylation; D000077209:Decitabine; D006801:Humans; D007680:Kidney Neoplasms / Q000235:genetics*; D019717:Tissue Inhibitor of Metalloproteinase-3 / Q000235:genetics*
D019717:Tissue Inhibitor of Metalloproteinase-3; D000077209:Decitabine; D001374:Azacitidine