Purpose: Deletions of 8p and gains of 8q belong to the most frequent cytogenetic alterations in prostate cancer. The target genes of these alterations and their biological significance are unknown.Experimental Design: To determine the relationship between chromosome 8 changes, and prostate cancer phenotype and prognosis, a set of 1.954 fully annotated prostate cancers were analyzed in a tissue microarray format by fluorescence in situ hybridization.Results: Both 8p deletions and 8q gains increased in number during different stages of prostate cancer progression. 8p deletions/8q gains were found in 26.1%/4.8% of 1,239 pT 2 cancers, 38.5%/9.8% of 379 pT 3a cancers, 43.5%/8.9% of 237 pT 3b cancers, 40.7%/14.8% of 27 pT 4 cancers, 39.1%/34.8% of 23 nodal metastases, 51.9%/33.3% of 27 bone metastases, and 45.5%/59.9% of 22 hormone refractory cancers (P < 0.0001 each). Both 8p deletions and 8q gains were also significantly associated with high Gleason grade and with each other (P < 0.0001 each). In primary tumors, 8p deletions were seen in only 27.3% of 1,882 cancers without 8q gain but in 57.4% of 122 tumors with 8q gain (P < 0.0001). Among cancers treated with radical prostatectomy, 8p deletions (P = 0.003) and 8q gains (P = 0.02) were associated with biochemical tumor recurrence. However, multivariate analysis (including prostate-specific antigen, pT/pN stage, Gleason score, and surgical margin status) did not reveal any statistically independent effect of 8p or 8q alterations on biochemical tumor recurrence.Conclusions: 8p deletions and 8q gains are relatively rare in early stage prostate cancer but often develop during tumor progression. The prognostic effect does not seem to be strong enough to warrant clinical application. Clin Cancer Res; 16(1); 56-64. ©2010 AACR.Prostate cancer is the most frequently diagnosed malignancy and the second most frequent cause of cancerrelated death among western males (1).Currently, clinical prediction tools rely solely on clinical (clinical stage), serologic (prostate-specific antigen), and histologic variables (Gleason grading; ref. 2).Because the development and progression of cancer is driven by molecular alterations, the analysis of molecular features may eventually allow better prediction of the behavior of individual cancers.Alterations on the DNA level would be especially suitable as prognostic markers. DNA alterations have the advantage of being less vulnerable to perioperative and postoperative ischemia or fixation procedures than RNA or proteins (3, 4). Deletions of 8p and gains of 8q are among the most frequent genomic alterations in prostate cancer. Several studies have proposed a relationship between 8p−/8q+ with adverse histopathologic findings (5-11). Studies suggesting associations with prostatespecific antigen progression, however, were limited to <100 cancers (12)(13)(14). Whereas considerable evidence points toward a role of chromosome 8 changes in prostate cancer biology, it is also evident that much larger patient cohorts are now needed to further cl...

BackgroundHuman pancreatic ductal adenocarcinoma (PDAC) is one of the most aggressive and lethal malignancies in the world and despite great efforts in research types of treatment remain limited. A frequently detected alteration in PDACs is a truncated O-linked N-acetylgalactosamine (GalNAc) glycosylation with expression of the Tn antigen. Changes in O-glycosylation affect posttranslationally modified O-GalNAc proteins resulting in profound cellular alterations. Tn antigen is a tumor associated glycan detected in 75-90 % of PDACs and up to 67 % in its precursor lesions. Since the role of Tn antigen expression in PDAC is insufficiently understood we analyzed the impact of COSMC mediated Tn antigen expression in two human PDAC cell lines on cellular oncogenic properties.MethodsForced expression of Tn antigen on O-glycosylated proteins in pancreatic cancer cells was induced by lentiviral-mediated knockdown of the COSMC chaperone, which prevented O-glycan elongation beyond the initial GalNAcα1- residue on O-linked glycoproteins. Altered O-GalNAc glycosylation was analyzed in human pancreatic cancer cell lines Panc-1 and L3.6pl using Western and Far-Western blot as well as immunocytochemical techniques. To assess the biological implications of COSMC function on oncogenic properties, cell viability assays, scratch assays combined with live cell imaging, migration and apoptosis assays were performed. Lectin based glycoprotein enrichment with subsequent mass spectrometric analysis identified new cancer O-GalNAc modified proteins. Expression of Tn antigen bearing Nucleolin in patient derived PDAC tumor specimens was evaluated and correlated with clinicopathological data.ResultsTn antigen expression was induced on various O-GalNAc glycoproteins in COSMC deficient cell lines compared to the control. Proliferation was reduced (p < 0.001) in COSMC knockdown cells, whereas migration was increased (p < 0.001) and apoptosis was decreased (p = 0.03), highlighting the importance of Tn antigen expression on metastatic and anti-apoptotic behavior of PDAC derived cells. Nucleolin was identified as O-GalNAc modified protein in COSMC deficient PDAC cell lines. Interestingly, immunohistochemical staining and co-localization studies of patient derived PDACs revealed poor survival for patients with strong co-localization of Tn antigen and Nucleolin (p = 0.037).ConclusionThis study substantiates the influence of altered O-glycan (Tn/STn) expression on oncogenic properties in pancreatic cancer and identifies O-GalNAc modified Nucleolin as novel prognostic marker.Electronic supplementary materialThe online version of this article (doi:10.1186/s12943-015-0386-1) contains supplementary material, which is available to authorized users.

Aims/hypothesis IRS2 is an important molecular switch that mediates insulin signalling in the liver. IRS2 dysregulation is responsible for the phenomenon of selective insulin resistance that is observed in type 2 diabetes. We hypothesise that epigenetic mechanisms are involved in the regulation of IRS2 in the liver of obese and type 2 diabetic individuals. Methods DNA methylation of seven CpG sites was studied by bisulphite pyrosequencing and mRNA and microRNA (miRNA) expression was assessed by quantitative real-time PCR in liver biopsies of 50 obese non-diabetic and 31 obese type 2 diabetic participants, in a cross-sectional setting. Methylation-sensitive luciferase assays and electrophoretic mobility shift assays were performed. Furthermore, HepG2 cells were treated with insulin and high glucose concentrations to induce miRNA expression and IRS2 downregulation. Results We found a significant downregulation of IRS2 expression in the liver of obese individuals with type 2 diabetes (0.84 ± 0.08-fold change; p = 0.0833; adjusted p value [pa] = 0.0417; n = 31) in comparison with non-diabetic obese participants (n = 50). This downregulation correlated with hepatic IRS2 DNA methylation at CpG5. Additionally, CpG6, which is located in intron 1 of IRS2, was hypomethylated in type 2 diabetes; this site spans the sterol regulatory element binding transcription factor 1 (SREBF1) recognition motif, which likely acts as transcriptional repressor. The adjacent polymorphism rs4547213 (G>A) was significantly associated with DNA methylation at a specificity-protein-1 (SP1) binding site (CpG3). Moreover, DNA methylation of cg25924746, a CpG site located in the shore region of the IRS2 promoter-associated CpG island, was increased in the liver of individuals with type 2 diabetes, as compared with those without diabetes. A second epigenetic mechanism, upregulation of hepatic miRNA hsa-let-7e-5p (let-7e-5p) in obese individuals with type 2 diabetes (n = 29) vs non-diabetic obese individuals (n = 49) (1.2 ± 0.08-fold change; p = 0.0332; pa = 0.0450), is likely to act synergistically with altered IRS2 DNA methylation to decrease IRS2 expression. Mechanistic in vitro experiments demonstrated an acute upregulation of let-7e-5p expression and simultaneous IRS2 downregulation in a liver (HepG2) cell line upon hyperinsulinaemic and hyperglycaemic conditions. Conclusions/interpretation Our study highlights a new multi-layered epigenetic network that could be involved in subtle dysregulation of IRS2 in the liver of individuals with type 2 diabetes. This might lead to fine-tuning of IRS2 expression and is likely to be supplementary to the already known factors regulating IRS2 expression. Thereby, our findings could support the discovery of new diagnostic and therapeutic strategies for type 2 diabetes.

Hepatic thyroid hormone signaling has an important role in the development and progression of nonalcoholic steatohepatitis (NASH). While the systemic levels of thyroid hormone might remain stable, there is evidence that the intracellular signaling machinery consisting of transporters, deiodinases and receptors could be altered in NASH. However, clinical material from human liver biopsies of individuals with NASH has not been studied to date. In a cross-sectional study, we analyzed 85 liver biopsies from patients with different stages of NASH that underwent bariatric surgery. Using qPCR, we analyzed gene expression of thyroid hormone transporters NTCP (SLC10A1), MCT8 (SLC16A2) and OATP1C1 (SLCO1C1), thyroid hormone receptor α and β (THRA and THRB) and deiodinase type I, II and III (DIO1, DIO2, DIO3). The expression was correlated with serum TSH, triglyceride, HbA1c and NASH score and corrected for age or gender if required. While DIO2, DIO3 and SLCO1C1 were not expressed in human liver, we observed a significant negative correlation of THRB and DIO1 with age, and SLC16A2 with gender. THRB expression was also negatively associated with serum triglyceride levels and HbA1c. More importantly, its expression was inversely correlated with NASH score and further declined with age. Our data provide unique insight into the mRNA expression of thyroid hormone transporters, deiodinases and receptors in the human liver. The findings allow important conclusions on the intrahepatic mechanisms governing thyroid hormone action, indicating a possible tissue resistance to the circulating hormone in NASH, which becomes more prominent in advanced age.