RESUMO
BACKGROUND/AIMS: Epigenetic regulations play a role in the development and progression of cancer. Therefore, discovering novel epigenetically regulated genes could provide useful information in understanding cancer. Lamin A/C is an intermediate filament protein whose expression is reported to be suppressed in tissues of gastro-intestinal malignancies. We examined expression of lamin A/C in gastric and colorectal cancer cell lines and its association with DNA methylation. METHODOLOGY: The methylation status of CpG island in 19 gastric, 5 colorectal cancer cells and 1 normal colon cell line were examined with methylation-specific PCR using paired methylated and unmethylated primers. The level of mRNA expression of lamin A/C was detected using RT-PCR. RESULTS: Eighteen gastric cancer cell lines showed 95% unmethylation of lamin A/C and 1 cell line showed partial methylation. In colorectal cancer, only 1 out of 5 cancer cell lines (20%) was partially methylated and the remaining cell lines, including 1 normal colon cell line was unmethylated. With RT-PCR, all cell lines demonstrated mRNA expression of lamin A/C regardless of methylation status. CONCLUSIONS: We observed that the expression of lamin A/C was not suppressed in gastrointestinal cancer cell lines different from hematologic malignant cells and it is not regulated through DNA methylation.
