Independent polled mutations leading to complex gene expression differences in cattle

The molecular regulation of horn growth in ruminants is still poorly understood. To investigate this process, we collected 1019 hornless (polled) animals from different cattle breeds. High-density SNP genotyping confirmed the presence of two different polled associated haplotypes in Simmental and Holstein cattle co-localized on BTA 1. We refined the critical region of the Simmental polled mutation to 212 kb and identified an overlapping region of 932 kb containing the Holstein polled mutation. Subsequently, whole genome sequencing of polled Simmental and Holstein cows was used to determine polled associated genomic variants. By genotyping larger cohorts of animals with known horn status we found a single perfectly associated insertion/deletion variant in Simmental and other beef cattle confirming the recently published possible Celtic polled mutation. We identified a total of 182 sequence variants as candidate mutations for polledness in Holstein cattle, including an 80 kb genomic duplication and three SNPs reported before. For the first time we showed that hornless cattle with scurs are obligate heterozygous for one of the polled mutations. This is in contrast to published complex inheritance models for the bovine scurs phenotype. Studying differential expression of the annotated genes and loci within the mapped region on BTA 1 revealed a locus (LOC100848215), known in cow and buffalo only, which is higher expressed in fetal tissue of wildtype horn buds compared to tissue of polled fetuses. This implicates that the presence of this long noncoding RNA is a prerequisite for horn bud formation. In addition, both transcripts associated with polledness in goat and sheep (FOXL2 and RXFP2), show an overexpression in horn buds confirming their importance during horn development in cattle.

Thyroid antibody status, subclinical hypothyroidism, and the risk of coronary heart disease: an individual participant data analysis.

CONTEXT Subclinical hypothyroidism has been associated with increased risk of coronary heart disease (CHD), particularly with thyrotropin levels of 10.0 mIU/L or greater. The measurement of thyroid antibodies helps predict the progression to overt hypothyroidism, but it is unclear whether thyroid autoimmunity independently affects CHD risk. OBJECTIVE The objective of the study was to compare the CHD risk of subclinical hypothyroidism with and without thyroid peroxidase antibodies (TPOAbs). DATA SOURCES AND STUDY SELECTION A MEDLINE and EMBASE search from 1950 to 2011 was conducted for prospective cohorts, reporting baseline thyroid function, antibodies, and CHD outcomes. DATA EXTRACTION Individual data of 38 274 participants from six cohorts for CHD mortality followed up for 460 333 person-years and 33 394 participants from four cohorts for CHD events. DATA SYNTHESIS Among 38 274 adults (median age 55 y, 63% women), 1691 (4.4%) had subclinical hypothyroidism, of whom 775 (45.8%) had positive TPOAbs. During follow-up, 1436 participants died of CHD and 3285 had CHD events. Compared with euthyroid individuals, age- and gender-adjusted risks of CHD mortality in subclinical hypothyroidism were similar among individuals with and without TPOAbs [hazard ratio (HR) 1.15, 95% confidence interval (CI) 0.87-1.53 vs HR 1.26, CI 1.01-1.58, P for interaction = .62], as were risks of CHD events (HR 1.16, CI 0.87-1.56 vs HR 1.26, CI 1.02-1.56, P for interaction = .65). Risks of CHD mortality and events increased with higher thyrotropin, but within each stratum, risks did not differ by TPOAb status. CONCLUSIONS CHD risk associated with subclinical hypothyroidism did not differ by TPOAb status, suggesting that biomarkers of thyroid autoimmunity do not add independent prognostic information for CHD outcomes.

Subclinical thyroid dysfunction and the risk for fractures: a systematic review and meta-analysis.

BACKGROUND Data on the association between subclinical thyroid dysfunction and fractures conflict. PURPOSE To assess the risk for hip and nonspine fractures associated with subclinical thyroid dysfunction among prospective cohorts. DATA SOURCES Search of MEDLINE and EMBASE (1946 to 16 March 2014) and reference lists of retrieved articles without language restriction. STUDY SELECTION Two physicians screened and identified prospective cohorts that measured thyroid function and followed participants to assess fracture outcomes. DATA EXTRACTION One reviewer extracted data using a standardized protocol, and another verified data. Both reviewers independently assessed methodological quality of the studies. DATA SYNTHESIS The 7 population-based cohorts of heterogeneous quality included 50,245 participants with 1966 hip and 3281 nonspine fractures. In random-effects models that included the 5 higher-quality studies, the pooled adjusted hazard ratios (HRs) of participants with subclinical hyperthyroidism versus euthyrodism were 1.38 (95% CI, 0.92 to 2.07) for hip fractures and 1.20 (CI, 0.83 to 1.72) for nonspine fractures without statistical heterogeneity (P = 0.82 and 0.52, respectively; I2= 0%). Pooled estimates for the 7 cohorts were 1.26 (CI, 0.96 to 1.65) for hip fractures and 1.16 (CI, 0.95 to 1.42) for nonspine fractures. When thyroxine recipients were excluded, the HRs for participants with subclinical hyperthyroidism were 2.16 (CI, 0.87 to 5.37) for hip fractures and 1.43 (CI, 0.73 to 2.78) for nonspine fractures. For participants with subclinical hypothyroidism, HRs from higher-quality studies were 1.12 (CI, 0.83 to 1.51) for hip fractures and 1.04 (CI, 0.76 to 1.42) for nonspine fractures (P for heterogeneity = 0.69 and 0.88, respectively; I2 = 0%). LIMITATIONS Selective reporting cannot be excluded. Adjustment for potential common confounders varied and was not adequately done across all studies. CONCLUSION Subclinical hyperthyroidism might be associated with an increased risk for hip and nonspine fractures, but additional large, high-quality studies are needed. PRIMARY FUNDING SOURCE Swiss National Science Foundation.

NOTCH ligands JAG1 and JAG2 as critical pro-survival factors in childhood medulloblastoma.

Medulloblastoma (MB), the most common pediatric malignant brain cancer, typically arises as pathological result of deregulated developmental pathways, including the NOTCH signaling cascade. Unlike the evidence supporting a role for NOTCH receptors in MB development, the pathological functions of NOTCH ligands remain largely unexplored. By examining the expression in large cohorts of MB primary tumors, and in established in vitro MB models, this research study demonstrates that MB cells bear abnormal levels of distinct NOTCH ligands. We explored the potential association between NOTCH ligands and the clinical outcome of MB patients, and investigated the rational of inhibiting NOTCH signaling by targeting specific ligands to ultimately provide therapeutic benefits in MB. The research revealed a significant over-expression of ligand JAG1 in the vast majority of MBs, and proved that JAG1 mediates pro-proliferative signals via activation of NOTCH2 receptor and induction of HES1 expression, thus representing an attractive therapeutic target. Furthermore, we could identify a clinically relevant association between ligand JAG2 and the oncogene MYC, specific for MYC-driven Group 3 MB cases. We describe for the first time a mechanistic link between the oncogene MYC and NOTCH pathway in MB, by identifying JAG2 as MYC target, and by showing that MB cells acquire induced expression of JAG2 through MYC-induced transcriptional activation. Finally, the positive correlation of MYC and JAG2 also with aggressive anaplastic tumors and highly metastatic MB stages suggested that high JAG2 expression may be useful as additional marker to identify aggressive MBs.

Vocational identity trajectories: Differences in personality and development of well-being

This person-centred study investigated the longitudinal patterns of vocational identity development in relation to personality, the development of well-being, gender, nationality and the attended school track among two cohorts of Swiss adolescents in 8th or 9th grade (N = 269) and in 11th or 12th grade (N = 230). The results confirmed the existence of four identity statuses, namely, achievement, foreclosure, moratorium and diffusion. Forty-two per cent of students showed progressive patterns of identity development, while 37% remained in their identity status over time. Students with different statuses and status change patterns differed significantly in their personality traits. Higher neuroticism related to the emergence of identity exploration over time, while conscientiousness related to maintaining or achieving a sense of identity commitment in terms of achievement or foreclosure. Controlling for the effects of socio-demographics and personality traits, students who reached or maintained a state characterized by identity clarity and commitment showed a relative increase in life satisfaction, while those entering a state of identity crisis or exploration showed a decrease in life satisfaction. Copyright © 2011 John Wiley & Sons, Ltd.

Investigation of IL-23 (p19, p40) and IL-23R identifies nuclear expression of IL-23 p19 as a favorable prognostic factor in colorectal cancer: a retrospective multicenter study of 675 patients.

IL-23 is a heterodimeric cytokine involved in inflammatory diseases; its role in cancer progression is controversial. Here we analyse the expression of IL-23 subunits (p40 and p19) and IL-23R in colorectal cancer with regard to disease progression, clinical-pathological and molecular aspects. Immunohistochemistry for IL-23p19, IL-23p40, IL-23R and CD8 was performed on a multi-punch tissue microarray of 195 colorectal cancers (cohort 1), matched normal tissue, adenoma and lymph node metastases. Results were compared with clinical-pathological features and CD8+ T-cell counts, then validated on two patient cohorts (cohort 2: n=341, cohort 3: n=139). Cytoplasmic/membranous expression of IL-23 (p19 and p40 subunits) and IL-23R, respectively were over-expressed in carcinomas versus adenomas and normal tissues (p<0.0001) but were reduced in lymph node metastases (p<0.0001). Nuclear IL-23p19 expression was observed in 23.1% and was associated with early TNM stage (p=0.0186), absence of venous (p=0.0124) and lymphatic invasion (p=0.01493), favorable survival (p=0.014) and absence of distant metastasis (p=0.0146; specificity: 100%). This unexpected cellular localization was confirmed by cell fractionation. The beneficial effect of nuclear IL-23p19 was restricted to tumours with CD8+ high counts. Results were validated on Cohorts 2/3. This multicenter study underlines the possible CD8(+)--dependency and beneficial effect of nuclear IL-23p19 on overall patient survival.

Circulating microRNA profiling in patients with advanced non-squamous NSCLC receiving bevacizumab/erlotinib followed by platinum-based chemotherapy at progression (SAKK 19/05).

OBJECTIVES Molecular subclassification of non small-cell lung cancer (NSCLC) is essential to improve clinical outcome. This study assessed the prognostic and predictive value of circulating micro-RNA (miRNA) in patients with non-squamous NSCLC enrolled in the phase II SAKK (Swiss Group for Clinical Cancer Research) trial 19/05, receiving uniform treatment with first-line bevacizumab and erlotinib followed by platinum-based chemotherapy at progression. MATERIALS AND METHODS Fifty patients with baseline and 24 h blood samples were included from SAKK 19/05. The primary study endpoint was to identify prognostic (overall survival, OS) miRNA's. Patient samples were analyzed with Agilent human miRNA 8x60K microarrays, each glass slide formatted with eight high-definition 60K arrays. Each array contained 40 probes targeting each of the 1347 miRNA. Data preprocessing included quantile normalization using robust multi-array average (RMA) algorithm. Prognostic and predictive miRNA expression profiles were identified by Spearman's rank correlation test (percentage tumor shrinkage) or log-rank testing (for time-to-event endpoints). RESULTS Data preprocessing kept 49 patients and 424 miRNA for further analysis. Ten miRNA's were significantly associated with OS, with hsa-miR-29a being the strongest prognostic marker (HR=6.44, 95%-CI 2.39-17.33). Patients with high has-miR-29a expression had a significantly lower survival at 10 months compared to patients with a low expression (54% versus 83%). Six out of the 10 miRNA's (hsa-miRN-29a, hsa-miR-542-5p, hsa-miR-502-3p, hsa-miR-376a, hsa-miR-500a, hsa-miR-424) were insensitive to perturbations according to jackknife cross-validation on their HR for OS. The respective principal component analysis (PCA) defined a meta-miRNA signature including the same 6 miRNA's, resulting in a HR of 0.66 (95%-CI 0.53-0.82). CONCLUSION Cell-free circulating miRNA-profiling successfully identified a highly prognostic 6-gene signature in patients with advanced non-squamous NSCLC. Circulating miRNA profiling should further be validated in external cohorts for the selection and monitoring of systemic treatment in patients with advanced NSCLC.

Role of plerixafor in autologous stem cell mobilization with vinorelbine chemotherapy and granulocyte-colony stimulating factor in patients with myeloma: a phase II study (PAV-trial)

Current practice in Switzerland for the mobilization of autologous stem cells in patients with myeloma is combining vinorelbine chemotherapy and granulocyte-colony stimulating factor (G-CSF) cytokine stimulation. We prospectively investigated adding intravenous plerixafor to the vinorelbine/G-CSF combination (VGP), and compared it with vinorelbine/plerixafor (VP) and G-CSF/plerixafor (GP) combinations. In a final cohort (VP-late), plerixafor was given on the first day of CD34 + cells increasing to > 15 000/mL peripheral blood. Four consecutive cohorts of 10 patients with myeloma were studied. We observed that intravenously administered plerixafor can be safely combined with vinorelbine/G-CSF. VGP was superior in mobilizing peripheral stem and progenitor cells compared to the three double combinations (VP, GP and VP-late), and GP mobilized better than VP. Our data indicate that the triple combination of VGP is an efficient strategy to collect autologous CD34 + cells, with G-CSF contributing predominantly in this concept. Plerixafor can be safely added to G-CSF and/or vinorelbine chemotherapy.

Chondroitin sulfate proteoglycan CSPG4 as a novel hypoxia-sensitive marker in pancreatic tumors.

CSPG4 marks pericytes, undifferentiated precursors and tumor cells. We assessed whether the shed ectodomain of CSPG4 (sCSPG4) might circulate and reflect potential changes in CSPG4 tissue expression (pCSPG4) due to desmoplastic and malignant aberrations occurring in pancreatic tumors. Serum sCSPG4 was measured using ELISA in test (n = 83) and validation (n = 221) cohorts comprising donors (n = 11+26) and patients with chronic pancreatitis (n = 11+20) or neoplasms: benign (serous cystadenoma SCA, n = 13+20), premalignant (intraductal dysplastic IPMNs, n = 9+55), and malignant (IPMN-associated invasive carcinomas, n = 4+14; ductal adenocarcinomas, n = 35+86). Pancreatic pCSPG4 expression was evaluated using qRT-PCR (n = 139), western blot analysis and immunohistochemistry. sCSPG4 was found in circulation, but its level was significantly lower in pancreatic patients than in donors. Selective maintenance was observed in advanced IPMNs and PDACs and showed a nodal association while lacking prognostic relevance. Pancreatic pCSPG4 expression was preserved or elevated, whereby neoplastic cells lacked pCSPG4 or tended to overexpress without shedding. Extreme pancreatic overexpression, membranous exposure and tissue(high)/sera(low)-discordance highlighted stroma-poor benign cystic neoplasm. SCA is known to display hypoxic markers and coincide with von-Hippel-Lindau and Peutz-Jeghers syndromes, in which pVHL and LBK1 mutations affect hypoxic signaling pathways. In vitro testing confined pCSPG4 overexpression to normal mesenchymal but not epithelial cells, and a third of tested carcinoma cell lines; however, only the latter showed pCSPG4-responsiveness to chronic hypoxia. siRNA-based knockdowns failed to reduce the malignant potential of either normoxic or hypoxic cells. Thus, overexpression of the newly established conditional hypoxic indicator, CSPG4, is apparently non-pathogenic in pancreatic malignancies but might mark distinct epithelial lineage and contribute to cell polarity disorders. Surficial retention on tumor cells renders CSPG4 an attractive therapeutic target. Systemic 'drop and restoration' alterations accompanying IPMN and PDAC progression indicate that the interference of pancreatic diseases with local and remote shedding/release of sCSPG4 into circulation deserves broad diagnostic exploration.

CYP3A5*3 and POR*28 genetic variants influence the required dose of tacrolimus in heart transplant recipients

BACKGROUND After heart transplantation (HTx), the interindividual pharmacokinetic variability of immunosuppressive drugs represents a major therapeutic challenge due to the narrow therapeutic window between over-immunosuppression causing toxicity and under-immunosuppression leading to graft rejection. Although genetic polymorphisms have been shown to influence pharmacokinetics of immunosuppressants, data in the context of HTx are scarce. We thus assessed the role of genetic variation in CYP3A4, CYP3A5, POR, NR1I2, and ABCB1 acting jointly in immunosuppressive drug pathways in tacrolimus (TAC) and ciclosporin (CSA) dose requirement in HTx recipients. METHODS Associations between 7 functional genetic variants and blood dose-adjusted trough (C0) concentrations of TAC and CSA at 1, 3, 6, and 12 months after HTx were evaluated in cohorts of 52 and 45 patients, respectively. RESULTS Compared with CYP3A5 nonexpressors (*3/*3 genotype), CYP3A5 expressors (*1/*3 or *1/*1 genotype) required around 2.2- to 2.6-fold higher daily TAC doses to reach the targeted C0 concentration at all studied time points (P ≤ 0.003). Additionally, the POR*28 variant carriers showed higher dose-adjusted TAC-C0 concentrations at all time points resulting in significant differences at 3 (P = 0.025) and 6 months (P = 0.047) after HTx. No significant associations were observed between the genetic variants and the CSA dose requirement. CONCLUSIONS The CYP3A5*3 variant has a major influence on the required TAC dose in HTx recipients, whereas the POR*28 may additionally contribute to the observed variability. These results support the importance of genetic markers in TAC dose optimization after HTx.

Outcomes after endovascular or open repair for degenerative descending thoracic aortic aneurysm using linked hospital data.

BACKGROUND The population-based effectiveness of thoracic endovascular aortic repair (TEVAR) versus open surgery for descending thoracic aortic aneurysm remains in doubt. METHODS Patients aged over 50 years, without a history of aortic dissection, undergoing repair of a thoracic aortic aneurysm between 2006 and 2011 were assessed using mortality-linked individual patient data from Hospital Episode Statistics (England). The principal outcomes were 30-day operative mortality, long-term survival (5 years) and aortic-related reinterventions. TEVAR and open repair were compared using crude and multivariable models that adjusted for age and sex. RESULTS Overall, 759 patients underwent thoracic aortic aneurysm repair, mainly for intact aneurysms (618, 81·4 per cent). Median ages of TEVAR and open cohorts were 73 and 71 years respectively (P < 0·001), with more men undergoing TEVAR (P = 0·004). For intact aneurysms, the operative mortality rate was similar for TEVAR and open repair (6·5 versus 7·6 per cent; odds ratio 0·79, 95 per cent confidence interval (c.i.) 0·41 to 1·49), but the 5-year survival rate was significantly worse after TEVAR (54·2 versus 65·6 per cent; adjusted hazard ratio 1·45, 95 per cent c.i. 1·08 to 1·94). After 5 years, aortic-related mortality was similar in the two groups, but cardiopulmonary mortality was higher after TEVAR. TEVAR was associated with more aortic-related reinterventions (23·1 versus 14·3 per cent; adjusted HR 1·70, 95 per cent c.i. 1·11 to 2·60). There were 141 procedures for ruptured thoracic aneurysm (97 TEVAR, 44 open), with TEVAR showing no significant advantage in terms of operative mortality. CONCLUSION In England, operative mortality for degenerative descending thoracic aneurysm was similar after either TEVAR or open repair. Patients who had TEVAR appeared to have a higher reintervention rate and worse long-term survival, possibly owing to cardiopulmonary morbidity and other selection bias.

Bcl-2 predicts response to neoadjuvant chemotherapy and is overexpressed in lymph node metastases of urothelial cancer of the bladder

PURPOSE To assess whether Bcl-2, an inhibitor of the apoptotic cascade, can predict response to neoadjuvant chemotherapy in patients with urothelial cancer of the bladder (UCB). METHODS Bcl-2 expression was analyzed in 2 different tissue microarrays (TMAs). One TMA was constructed of primary tumors and their corresponding lymph node (LN) metastases from 152 patients with chemotherapy-naive UCB treated by cystectomy and pelvic lymphadenectomy (chemotherapy-naive TMA cohort). The other TMA was constructed of tumor samples obtained from 55 patients with UCB before neoadjuvant chemotherapy (transurethral resection of the bladder cancer) and after cystectomy with pelvic lymphadenectomy (residual primary tumor [ypT+], n = 38); residual LN metastases [ypN+], n = 24) (prechemotherapy/postchemotherapy TMA cohort). Bcl-2 overexpression was defined as 10% or more cancer cells showing cytoplasmic immunoreactivity. RESULTS In both TMA cohorts, Bcl-2 overexpression was significantly (P<0.05) more frequent in LN metastases than in primary tumors (chemotherapy-naive TMA group: 18/148 [12%] in primary tumors vs. 39/143 [27%] in metastases; postchemotherapy TMA: ypT+7/35 [20%] vs. ypN+11/19 [58%]). In the neoadjuvant setting, patients with Bcl-2 overexpression in transurethral resection of the bladder cancer specimens showed significantly (P = 0.04) higher ypT stages and less regression in their cystectomy specimens than did the control group, and only one-eighth (13%) had complete tumor regression (ypT0 ypN0). In survival analyses, only histopathological parameters added significant prognostic information. CONCLUSIONS Bcl-2 overexpression in chemotherapy-naive primary bladder cancer is related to poor chemotherapy response and might help to select likely nonresponders.

Early development of human lymphomas in a prostate cancer xenograft program using triple knock-out immunocompromised mice

BACKGROUND There is an urgent need for preclinical models of prostate cancer; however, clinically relevant patient-derived prostate cancer xenografts (PDXs) are demanding to establish. METHODS Sixty-seven patients who were undergoing palliative transurethral surgery or radical prostatectomy for histologically confirmed, clinically relevant prostate cancer were included in the study. Fresh prostate cancer tissue was identified by frozen analysis in 48 patients. The cancer tissue was transplanted subcutaneously and under the renal capsule of NSG and NOG mice supplemented with human testosterone. All growing PDXs were evaluated by histology and immunohistochemistry. RESULTS Early assessment of the animals at least three months after transplantation included 27/48 (56.3%) eligible PDX cohorts. PDX growth was detected in 10/27 (37%) mouse cohorts. Eight of the ten PDXs were identified as human donor derived lymphomas, including seven Epstein Barr virus (EBV)-positive diffuse large B-cell lymphomas and one EBV-negative peripheral T-cell lymphoma. One sample consisted of benign prostatic tissue, and one sample comprised a benign epithelial cyst. Prostate cancer was not detected in any of the samples. CONCLUSIONS Tumors that arise within the first three months after prostate cancer xenografting may represent patient-derived EBV-positive lymphomas in up to 80% of the early growing PDXs when using triple knockout NSG immunocompromised mice. Therefore, lymphoma should be excluded in prostate cancer xenografts that do not resemble typical prostatic adenocarcinoma. Prostate 9999: XX-XX, 2014. © 2015 Wiley Periodicals, Inc.

Combination of expression levels of miR-21 and miR-126 is associated with cancer-specific survival in clear-cell renal cell carcinoma

BACKGROUND Renal cell carcinoma (RCC) is marked by high mortality rate. To date, no robust risk stratification by clinical or molecular prognosticators of cancer-specific survival (CSS) has been established for early stages. Transcriptional profiling of small non-coding RNA gene products (miRNAs) seems promising for prognostic stratification. The expression of miR-21 and miR-126 was analysed in a large cohort of RCC patients; a combined risk score (CRS)-model was constructed based on expression levels of both miRNAs. METHODS Expression of miR-21 and miR-126 was evaluated by qRT-PCR in tumour and adjacent non-neoplastic tissue in n = 139 clear cell RCC patients. Relation of miR-21 and miR-126 expression with various clinical parameters was assessed. Parameters were analysed by uni- and multivariate COX regression. A factor derived from the z-score resulting from the COX model was determined for both miRs separately and a combined risk score (CRS) was calculated multiplying the relative expression of miR-21 and miR-126 by this factor. The best fitting COX model was selected by relative goodness-of-fit with the Akaike information criterion (AIC). RESULTS RCC with and without miR-21 up- and miR-126 downregulation differed significantly in synchronous metastatic status and CSS. Upregulation of miR-21 and downregulation of miR-126 were independently prognostic. A combined risk score (CRS) based on the expression of both miRs showed high sensitivity and specificity in predicting CSS and prediction was independent from any other clinico-pathological parameter. Association of CRS with CSS was successfully validated in a testing cohort containing patients with high and low risk for progressive disease. CONCLUSIONS A combined expression level of miR-21 and miR-126 accurately predicted CSS in two independent RCC cohorts and seems feasible for clinical application in assessing prognosis.

Epidermal growth factor receptor (EGFR) is an independent adverse prognostic factor in esophageal adenocarcinoma patients treated with cisplatin-based neoadjuvant chemotherapy.

Neoadjuvant platin-based therapy is accepted as a standard therapy for advanced esophageal adenocarcinoma (EAC). Patients who respond have a better survival prognosis, but still a significant number of responder patients die from tumor recurrence. Molecular markers for prognosis in neoadjuvantly treated EAC patients have not been identified yet. We investigated the epidermal growth factor receptor (EGFR) in prognosis and chemotherapy resistance in these patients. Two EAC patient cohorts, either treated by neoadjuvant cisplatin-based chemotherapy followed by surgery (n=86) or by surgical resection (n=46) were analyzed for EGFR protein expression and gene copy number. Data were correlated with clinical and histopathological response, disease-free and overall survival. In case of EGFR overexpression, the prognosis for neoadjuvant chemotherapy responders was poor as in non-responders. Responders had a significantly better disease-free survival than non-responders only if EGFR expression level (p=0.0152) or copy number (p=0.0050) was low. Comparing neoadjuvantly treated patients and primary resection patients, tumors of non-responder patients more frequently exhibited EGFR overexpression, providing evidence that EGFR is a factor for indicating chemotherapy resistance. EGFR overexpression and gene copy number are independent adverse prognostic factors for neoadjuvant chemotherapy-treated EAC patients, particularly for responders. Furthermore, EGFR overexpression is involved in resistance to cisplatin-based neoadjuvant chemotherapy.