Methylation Profiling of Urothelial Carcinoma in Bladder Biopsy and Urine

Multiplexed Methylation Profiles of Tumor Suppressor Genes in Bladder Cancer

“…The most frequent methylated genes previously reported in urinary specimens of patients with bladder cancer were BRCA1, 38 RARB, 39 and CDH13 38 ; these genes also occurred in bladder cancer cell lines and tumors. The detection of distinct methylation profiles between noninvasive and invasive bladder tumors is in concordance with genes previously reported as methylated in bladder cancer by standard MS-PCR, [32][33][34][35][36][37][38][39] despite the fact that different CpG dinucleotides could be targeted by the MS-MLPA and MS-PCR methods. The MS-MLPA method allowed identification of several new and possibly interesting epigenetic alterations (eg, MSH6, WT1, and THBS1 genes), serving to gain more insight into the development of bladder carcinomas.…”

“…Having information of epigenetic alterations reported for several genes included in the MS-MLPA under analyses in bladder tumors, and even in urinary specimens by an independent method, [32][33][34][35][36][37][38][39] served to support our findings in urinary specimens. A correlation of epigenetic aberrations with bladder cancer histopathological variables was reported in numerous studies 8 -12,32-39 using techniques other than MS-MLPA.…”

“…15 The advantages of the MS-MLPA technique as an alter- native for MS-PCR include allowing screening of more than 25 predefined promoter methylation candidates in one single step using a low amount of DNA (100 to 200 ng), 16 which is feasible using DNA extracted from tissue (even in formalin-fixed material) 18 ; providing semiquantitative data; and requiring only standard laboratory equipment. Furthermore, the (potentially) troublesome bisulfite conversion of unmethylated cytosines required for MS-PCR [31][32][33][34][35][36][37][38][39] can be omitted in MS-MLPA using methylationsensitive digestion. The present study showed that these generally acknowledged advantages can also be translated to investigate methylation in body fluids in a multiplexed manner.…”

Hypermethylation in bladder cancer: biological pathways and translational applications

“…Interestingly, not only the CDKN2A is altered by hypermethylation but also RB is inactivated through mutation or deletion in bladder cancer. P16 [46,[58][59][60][65][66][67][68][69][70][71][72][73][74][75][76][77][78][79], p14 [71,81,83], and Cyclin D2 (CCND2) [59,74,[84][85][86][87][88][89] are among the most studied and frequently methylated genes Yes [110] Yes [110] Yes [110] [ 46, 110] Yes [127] Yes [47] [ 47] PMF1 77.6-88.1%…”

“…It remains to be evaluated whether bladder tumor subtypes with a silenced MGMT gene might more often contain a mutation in the TP53 tumor suppressor gene or others, indicating that loss of MGMT might cause the ensuing mutations. Other genes known to play a role in DNA repair that have been shown to be frequently hypermethylated in bladder cancer include glutation transferase 1 gene (GSTP1) [46,58,59,67,68,72,73,84,91,93], the mutL homolog 1, colon cancer, nonpolyposis type 2 gene (MLH1) [46,68,72,87,95], the adenomatous poliposis coli gene (APC) [57,60,71,83,84,86,93], the ataxia telangiectasia mutated gene (ATM) [58,59,87], the Mut S homolog 6 gene (MSH6) [58,59], the cytochrome c oxidase subunit gene (COX2) [95], the breast cancer 1 and 2, early onset genes (BRCA1 and BRCA2) [58,59], or the tumor suppressor gene TP53 [58][59][60].…”