The clinical significance of ERBB2 amplification/overexpression in gastric cancer remains unclear. In this study, we evaluated the ERBB2 status in 463 gastric carcinomas using immunohistochemistry (IHC) and fluorescence in situ hybridisation (FISH), and compared the findings with histopathological characteristics and with disease-specific survival. ERBB2 overexpression (2 þ and 3 þ ) and amplification (ratio ERBB2/CEP17X2) were found in 43 (9.3%) and 38 (8.2%) gastric carcinomas, respectively. Perfect IHC/FISH correlation was found for the 19 cases scored as 0 (all negative by FISH), and also for the 25 cases scored as 3 þ (all positive by FISH). One out of six carcinomas scored as 1 þ and 12 out of 18 carcinomas scored as 2 þ were positive by FISH. ERBB2 amplification was associated with gastric carcinomas of intestinal type (P ¼ 0.007) and with an expansive growth pattern (P ¼ 0.021). ERBB2 amplification was detected in both histological components of two mixed carcinomas, indicating a common clonal origin. A statistically significant association was found between ERBB2 amplification and worse survival in patients with expansive gastric carcinomas (P ¼ 0.011). We conclude that ERBB2 status may have clinical significance in subsets of gastric cancer patients, and that further studies are warranted to evaluate whether patients whose gastric carcinomas present ERBB2 amplification/overexpression may benefit from therapy targeting this surface receptor. Despite the trend for decreasing incidence, gastric adenocarcinoma is still the second cause of cancer death worldwide (Parkin et al, 2005). The overall 5-year survival rate of patients with resectable gastric cancer ranges from 10 to 30% (Harrison et al, 1998;Msika et al, 2000;Green et al, 2002). Apart from surgical resection, evaluation of available therapies, both neo-adjuvant and adjuvant, provides conflicting results regarding the clinical outcome. Several meta-analyses have been published in an attempt to address the discrepancies reported in the literature, but recommendation for adjuvant chemotherapy in Western centres is still not consensual (Hermans et al, 1993;Earle and Maroun, 1999;Mari et al, 2000;Gianni et al, 2001;Janunger et al, 2001Janunger et al, , 2002Hu et al, 2002). The most important prognostic factor established for gastric cancer is the TNM stage, which is determined by the depth of invasion, involvement of lymph nodes, and distant metastasis. However, clinical outcome varies among patients in the same stage (Park et al, 2006). Therefore prognostic factors other than the TNM stage, as well as new therapies, would be of great value for gastric cancer patients.The ERBB2 gene maps to 17q12 -q21 and encodes a 185-kDa transmembrane tyrosine kinase receptor (p185), which is a member of the epidermal growth factor receptor family (Xu et al, 1984;Akiyama et al, 1986;Popescu et al, 1989). In breast carcinomas, ERBB2 functions as an oncogene, as amplification of the gene induces protein overexpression in the cell membrane (Slamon et al, 1989). Besides ...

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Invasive bladder tumours express the cell-surface Sialyl-Tn (STn) antigen, which stems from a premature stop in protein O-glycosylation. The STn antigen favours invasion, immune escape, and possibly chemotherapy resistance, making it attractive for target therapeutics. However, the events leading to such deregulation in protein glycosylation are mostly unknown. Since hypoxia is a salient feature of advanced stage tumours, we searched into how it influences bladder cancer cells glycophenotype, with emphasis on STn expression. Therefore, three bladder cancer cell lines with distinct genetic and molecular backgrounds (T24, 5637 and HT1376) were submitted to hypoxia. To disclose HIF-1α-mediated events, experiments were also conducted in the presence of Deferoxamine Mesilate (Dfx), an inhibitor of HIF-1α proteasomal degradation. In both conditions all cell lines overexpressed HIF-1α and its transcriptionally-regulated protein CA-IX. This was accompanied by increased lactate biosynthesis, denoting a shift toward anaerobic metabolism. Concomitantly, T24 and 5637 cells acquired a more motile phenotype, consistent with their more mesenchymal characteristics. Moreover, hypoxia promoted STn antigen overexpression in all cell lines and enhanced the migration and invasion of those presenting more mesenchymal characteristics, in an HIF-1α-dependent manner. These effects were reversed by reoxygenation, demonstrating that oxygen affects O-glycan extension. Glycoproteomics studies highlighted that STn was mainly present in integrins and cadherins, suggesting a possible role for this glycan in adhesion, cell motility and invasion. The association between HIF-1α and STn overexpressions and tumour invasion was further confirmed in bladder cancer patient samples. In conclusion, STn overexpression may, in part, result from a HIF-1α mediated cell-survival strategy to adapt to the hypoxic challenge, favouring cell invasion. In addition, targeting STn-expressing glycoproteins may offer potential to treat tumour hypoxic niches harbouring more malignant cells.