Comparison of hypoxia transcriptome in vitro with in vivo gene expression in human bladder cancer

Hypoxia-inducible genes have been linked to the aggressive phenotype of cancer. However, nearly all work on hypoxia-regulated genes has been conducted in vitro on cell lines. We investigated the hypoxia transcriptome in primary human bladder cancer using cDNA microarrays to compare genes induced by hypoxia in vitro in bladder cancer cell line EJ28 with genes upregulated in 39 bladder tumour specimens (27 superficial and 12 invasive). We correlated array mRNA fold changes with carbonic anhydrase 9 (CA IX) staining of tumours as a surrogate marker of hypoxia. Of 6000 genes, 32 were hypoxia inducible in vitro more than two-fold, five of which were novel, including lactate transporter SLC16A3 and RNAse 4. Eight of 32 hypoxia-inducible genes in vitro were also upregulated on the vivo array. Vascular endothelial growth factor mRNA was upregulated two-fold by hypoxia and 2–18-fold in 31 out of 39 tumours. Glucose transporter 1 was also upregulated on both arrays mRNA, and fold changes on the in vivo array significantly correlated with CA IX staining of tumours (P=0.008). However, insulin-like growth factor binding protein 3 mRNA was the most strongly differentially expressed gene in both arrays and this confirmed its upregulation in urine of bladder cancer patients (n=157, P<0.01). This study defines genes suitable for an in vivo hypoxia ‘profile', shows the heterogeneity of the hypoxia response and describes new hypoxia-regulated genes

Spotlight on Differentially Expressed Genes in Urinary Bladder Cancer

INTRODUCTION: We previously identified common differentially expressed (DE) genes in bladder cancer (BC). In the present study we analyzed in depth, the expression of several groups of these DE genes. MATERIALS AND METHODS: Samples from 30 human BCs and their adjacent normal tissues were analyzed by whole genome cDNA microarrays, qRT-PCR and Western blotting. Our attention was focused on cell-cycle control and DNA damage repair genes, genes related to apoptosis, signal transduction, angiogenesis, as well as cellular proliferation, invasion and metastasis. Four publicly available GEO Datasets were further analyzed, and the expression data of the genes of interest (GOIs) were compared to those of the present study. The relationship among the GOI was also investigated. GO and KEGG molecular pathway analysis was performed to identify possible enrichment of genes with specific biological themes. RESULTS: Unsupervised cluster analysis of DNA microarray data revealed a clear distinction in BC vs. control samples and low vs. high grade tumors. Genes with at least 2-fold differential expression in BC vs. controls, as well as in non-muscle invasive vs. muscle invasive tumors and in low vs. high grade tumors, were identified and ranked. Specific attention was paid to the changes in osteopontin (OPN, SPP1) expression, due to its multiple biological functions. Similarly, genes exhibiting equal or low expression in BC vs. the controls were scored. Significant pair-wise correlations in gene expression were scored. GO analysis revealed the multi-facet character of the GOIs, since they participate in a variety of mechanisms, including cell proliferation, cell death, metabolism, cell shape, and cytoskeletal re-organization. KEGG analysis revealed that the most significant pathway was that of Bladder Cancer (p = 1.5×10(-31)). CONCLUSIONS: The present work adds to the current knowledge on molecular signature identification of BC. Such works should progress in order to gain more insight into disease molecular mechanisms

Artificial urinary sphincters for male stress urinary incontinence: current perspectives

Billy H Cordon,1 Nirmish Singla,1 Ajay K Singla2 1Department of Urology, University of Texas Southwestern Medical Center, Dallas, TX, 2Department of Urology, University of Toledo College of Medicine, Toledo, OH, USA Abstract: The artificial urinary sphincter (AUS), which has evolved over many years, has become a safe and reliable treatment for stress urinary incontinence and is currently the gold standard. After 4 decades of existence, there is substantial experience with the AUS. Today AUS is most commonly placed for postprostatectomy stress urinary incontinence. Only a small proportion of urologists routinely place AUS. In a survey in 2005, only 4% of urologists were considered high-volume AUS implanters, performing &gt;20 per year. Globally, ~11,500 AUSs are placed annually. Over 400 articles have been published regarding the outcomes of AUS, with a wide variance in success rates ranging from 61% to 100%. Generally speaking, the AUS has good long-term outcomes, with social continence rates of ~79% and high patient satisfaction usually between 80% and 90%. Despite good outcomes, a substantial proportion of patients, generally ~25%, will require revision surgery, with the rate of revision increasing with time. Complications requiring revision include infection, urethral atrophy, erosion, and mechanical failure. Most infections are gram-positive skin flora. Urethral atrophy and erosion lie on a spectrum resulting from the same problem, constant urethral compression. However, these two complications are managed differently. Mechanical failure is usually a late complication occurring on average later than infection, atrophy, or erosions. Various techniques may be used during revisions, including cuff relocation, downsizing, transcorporal cuff placement, or tandem cuff placement. Patient satisfaction does not appear to be affected by the need for revision as long as continence is restored. Additionally, AUS following prior sling surgery has comparable outcomes to primary AUS placement. Several new inventions are on the horizon, although none have been approved for use in the US at this point. Keywords: artificial urinary sphincter, stress urinary incontinence, post prostatectomy incontinence, prostheses and implants, revie