Genome-wide methylation profiling and the PI3K-AKT pathway analysis associated with smoking in urothelial cell carcinoma

摘要: Urothelial cell carcinoma (UCC) is the second most common genitourinary malignant disease in USA, and tobacco smoking major known risk factor for UCC development. Exposure to carcinogens, such as those contained smoke, directly or indirectly damage DNA, causing mutations, chromosomal deletion events epigenetic alterations UCC. Molecular studies have shown that chromosome 9 P53, RAS, RB PTEN mutations are among frequent Recent suggested continuous carcinogen exposure drives enhances selection of epigenetically altered cells UCC, predominantly invasive form disease. However, sequence molecular leads after smoke not well understood. To elucidate lead oncogenesis progression exposure, we developed an vitro cellular model smoking-induced SV-40 immortalized normal HUC1 human bladder epithelial were continuously exposed 0.1% cigarette extract (CSE) until transformation occurred. Morphological increased proliferation non-malignant urothelial observed 4 months (mo) treatment with CSE. Anchorage-independent growth assessed by soft agar assay increase migratory potential was 6 mo CSE treatment. By performing a PCR mRNA expression array specific PI3K-AKT pathway, found 26 genes upregulated 22 downregulated cells. Among genes, PTEN, FOXO1, MAPK1 PDK1 transformed cells, while AKT1, AKT2, HRAS, RAC1 upregulated. Validation RT-PCR western blot analysis then performed. Furthermore, genome-wide methylation revealed MCAM, DCC HIC1 hypermethylated CSE-treated when compared non-CSE The status these validated using quantitative methylation-specific (QMSP), confirming untreated controls. Therefore, our findings suggest signature could emerge from distinctive patterns genetic can be identified development cancer.