To assess the role of c-myc gene copy number alterations in bladder cancer, 87 bladder tumors were examined for c-myc aberrations by fluorescence in situ hybridization.
The data indicate that elevated mRNA expression as a consequence of increases in c-myc gene copy number often underlies Myc protein over-expression in bladder cancer.
We genotyped rs9642880 G>T on 8q24 and rs710521 A>G on 3q28 in a two-stage case-control study of bladder cancer to evaluate the association and further examined the expression of MYC.
Recently, a genome-wide single nucleotide polymorphism association study has identified a sequence variant 30 kb upstream of the c-Myc gene (allele T of rs9642880) that confers susceptibility to bladder cancer.
The reported risk alleles of rs798766 on TACC3 at 4p16 and rs9624880 on MYC at 8q24 were significantly associated with increased bladder cancer risk with P-values of 0.003 and 0.03, respectively.
Three previously established bladder cancer risk-associated SNPs (rs798766 in TACC3, rs9642880 in MYC, and rs2294008 in PSCA) were genotyped in 1,210 bladder cancer patients and 1,008 control subjects in Shanghai, China.
Inhibition of BRD4 decreased bladder cancer cell proliferation concomitantly with the accumulation of cell apoptosis in vitro and suppressed tumor growth in vivo We further found that suppression of BRD4 decreased the mRNA and protein levels of EZH2, which was reversed by ectopic expression of C-MYC In particular, individual silencing of BRD4 using shRNA or the BET inhibitor JQ1 strikingly diminished the recruitment of C-MYC to EZH2 promoter in bladder cancer.
Here we show that HDAC6 loss or inhibition reduces FGFR3 accumulation in cells made tumorigenic by ectopic expression of a mutant activated version of FGFR3 together with the MYC oncoprotein and in a bladder cancer cell line whose tumorigenicity is dependent on expression of a translocated version of FGFR3.
We discovered a positive feedback loop, in which the activation of p38 and AKT downstream from the altered FGFR3 upregulates <i>MYC</i> mRNA levels and stabilizes MYC protein, respectively, leading to the accumulation of MYC, which directly upregulates <i>FGFR3</i> expression by binding to active enhancers upstream from <i>FGFR3</i> Disruption of this FGFR3/MYC loop in bladder cancer cell lines by treatment with FGFR3, p38, AKT, or BET bromodomain inhibitors (JQ1) preventing <i>MYC</i> transcription decreased cell viability <i>in vitro</i> and tumor growth <i>in vivo</i> A relevance of this loop to human bladder tumors was supported by the positive correlation between <i>FGFR3</i> and <i>MYC</i> levels in tumors bearing <i>FGFR3</i> mutations, and the decrease in FGFR3 and MYC levels following anti-FGFR treatment in a PDX model bearing an <i>FGFR3</i> mutation.
Here, using shRNA-mediated gene silencing, immunoblotting, quantitative RT-PCR, anchorage-independent growth assay, and invasive assay, we found that XIAP's RING domain, but not its BIR domain, is crucial for XIAP-mediated up-regulation of c-Myc protein expression in human bladder cancer (BC) cells.
This study further explored the mechanism of the ERH gene in the metastasis of the T24 human bladder cancer cell line and found that ERH may regulate MYC gene expression.
Our findings suggest that circCDYL functions as a tumor suppressor in bladder cancer by down-regulating the expression of C-MYC, and this circular RNA might be used as a new target for bladder cancer therapy.
Then, the Cox proportional hazard regression model were employed to identify three key prognostic ARGs (JUN, MYC, and ITGA3), which were related with overall survival (OS) significantly in BC.
CONCLUSIONS FoxR2 knockdown decreases chemoresistance to cisplatin via the MYC pathway in bladder cancer cells, and this may be a target for overcoming chemoresistance in bladder cancer.