Promoter CpG methylation of caveolin-1 in sporadic colorectal cancer.
BACKGROUND
Caveolin-1 has been shown to be down-regulated in human colon cancer and involved in colon tumorigenesis. We investigated the mechanism.


METHODS
Cancerous and nearby non-cancerous tissues of 185 sporadic colorectal cancer samples were enrolled in this study. Methylation-specific PCR was performed to explore the mechanism of regulation of caveolin-1 gene expression.


RESULTS
Aberrant promoter methylation in the caveolin-1 gene was 3.8% and 5.9% for cancerous and nearby non-cancerous tissues, respectively. All the cancerous and non-cancerous tissue contained unmethylated promoters in the caveolin-1 gene. The methylation status of caveolin-1 had no clear relationship with age, cell grade, location of tumor or lymph node metastasis. However, female gender showed statistically significant difference (p=0.045). The immunohistochemistry study demonstrated that expression of caveolin-1 correlated with aberrant promoter methylation status in sporadic colorectal cancer tissues.


CONCLUSIONS
Our findings suggested that aberrant promoter methylation of the caveolin-1 gene may occur at the precancerous stage, regulated by gender-related factors and is associated with gene silencing of caveolin-1 in the development of colorectal cancer.
Department of Internal Medicine, Taipei Medical University Hospital, Taipei, Taiwan.
Shyr-Yi
SY
Lin
Kun-Tu
KT
Yeh
Willian Tzu-Liang
WT
Chen
Hung-Chang
HC
Chen
Shou-Tung
ST
Chen
Jan-Gowth
JG
Chang
D051242:Caveolin 1; D022461:Caveolins / Q000037:antagonists & inhibitors / Q000096:biosynthesis / Q000235:genetics*; D015179:Colorectal Neoplasms / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D018899:CpG Islands; D019175:DNA Methylation; D015536:Down-Regulation; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D020868:Gene Silencing; D006801:Humans; D008297:Male; D008875:Middle Aged; D016133:Polymerase Chain Reaction; D011230:Precancerous Conditions / Q000235:genetics / Q000378:metabolism; D011401:Promoter Regions, Genetic
C495540:CAV1 protein, human; D051242:Caveolin 1; D022461:Caveolins