Susanne Neiss

High Specificity of Quantitative Excision Repair Cross- Complementing 1 Messenger RNA Expression for Prediction of Minor Histopathological Response to Neoadjuvant Radiochemotherapy in Esophageal Cancer

Purpose: The excision repair cross-complementing 1 (ERCC1) gene is coding for a nucleotide excision repair protein involved in the repair of radiation- and chemotherapy-induced DNA damage. We examined the potential of quantitative ERCC1 mRNA expression to predict minor or major histopathological response to neoadjuvant radiochemotherapy (cisplatin, 5-fluorouracil, and 36 Gy of radiation) followed by transthoracic en bloc esophagectomy in patients with locally advanced esophageal cancer (cT2–4, Nx, M0). Experimental Design: Tissue samples were collected by endoscopic biopsy before treatment. RNA was isolated from biopsies, and quantitative real-time reverse transcriptase PCR assays were performed to determine ERCC1 mRNA expression. Relative mRNA levels (tumor/normal ratios) were calculated as (ERCC1/β-actin in tumor)/(ERCC1/β-actin in paired normal tissue). ERCC1 expression levels were correlated with the objective histopathological response in resected specimens. Histomorphological regression was defined as major response when resected specimens contained <10% of residual vital tumor cells or in case a pathologically complete response was achieved. Results: Twelve of 36 tumors showed a major histopathological response, and 24 of 36 showed a minor histopathological response. Relative expression levels of ERCC1 of >1.09 were not associated with a major histopathological response (sensitivity, 62.5%; specificity, 100%) and 15 of 24 patients with minor histopathological response to the delivered neoadjuvant radiochemotherapy could be unequivocally identified. This association of dichotomized relative ERCC1 mRNA expression and histopathological response was statistically significant (P < 0.001). Conclusions: Relative expression levels of ERCC1 mRNA determined by quantitative real-time reverse transcriptase-PCR appear highly specific to predict minor response to our neoadjuvant radiochemotherapy protocol in patients with locally advanced esophageal cancer and could be applied to prevent expensive, noneffective, and potentially harmful therapies in a substantial number (42%) of patients.

High Cyclooxygenase-2 Expression Following Neoadjuvant Radiochemotherapy Is Associated with Minor Histopathologic Response and Poor Prognosis in Esophageal Cancer

Purpose: High expression of cyclooxygenase-2 (COX-2) was shown to inhibit chemotherapy- and radiotherapy-induced apoptosis. We analyzed the association of COX-2 mRNA and protein expression with histomorphologic response to neoadjuvant radiochemotherapy in esophageal cancer. Experimental Design: Fifty-two patients with resectable esophageal cancers (cT2-4, Nx, and M0) received neoadjuvant radiochemotherapy (cisplatin, 5-5-fluorouracil, 36 Gy) followed by transthoracic en bloc esophagectomy. Histomorphologic regression was defined as major response when resected specimens contained less than 10% of residual vital tumor cells. RNA was isolated from endoscopic biopsies (paired tumor and normal tissue) before neoadjuvant treatment and quantitative real-time reverse transcriptase-PCR (Taqman) assays were done to determine COX-2 mRNA expression levels standardized for β-actin. COX-2 protein expression in pretreatment biopsies and post-therapeutic resection specimens was analyzed by immunostaining of tumor cells. Results: Median COX-2 mRNA expression levels were significantly (P < 0.0001) different between paired tumor (median, 2.2) and normal tissues (median, 0.159). Comparison of pre-therapeutic and posttherapeutic specimens showed a significant difference (P < 0.006) in COX-2 protein expression. Twelve of 52 tumors showed down-regulation and 3 of 52 showed up-regulation of COX-2 protein expression during neoadjuvant radiochemotherapy. High COX-2 protein expression in post-therapeutic resection specimens was significantly associated with minor histopathologic response (P < 0.04) and poor prognosis (5-year survival probabilities: 26.3 ± 8.2% for minor and 58.6% ± 12.9% for major histopathologic response; P < 0.01). Conclusion: High COX-2 protein expression following neoadjuvant radiochemotherapy in resection specimens is significantly associated with minor histopathologic response to neoadjuvant therapy and very poor prognosis.

COX-2 mRNA Expression is Significantly Increased in Acid-exposed Compared to Nonexposed Squamous Epithelium in Gastroesophageal Reflux Disease

BackgroundLittle is known about the role of cyclooxygenase (COX)-2 in gastroesophageal reflux disease (GERD) and the development of Barrett’s metaplasia. The objectives of this study were to further analyze COX-2 mRNA expression in patients with GERD compared to Barrett’s esophagus (BE) and Barrett’s cancer (BC).MethodsTissue samples from 110 patients with GERD (n = 43), BE (n = 20), and BC (n = 47) were obtained in routine upper GI endoscopy. Expression levels of COX-2 were measured by quantitative real-time reverse trancriptase polymerase chain reaction (RT-PCR). Also, 24-h pH monitoring was performed in all patients of the GERD study group and the DeMeester composite score was used to match COX-2 mRNA expression with the severity of acid exposure in the lower esophagus.ResultsCOX-2 mRNA is progressively upregulated within the metaplasia–dysplasia–adenocarcinoma (MDA) sequence (p = 0.001). COX-2 levels of the squamous epithelium in the distal esophagus from patients with GERD and a pathologic mean DeMeester score (>14.72) were significantly higher than in patients with normal DeMeester scores (p = 0.01).ConclusionIn summary our findings suggest that alterations in COX-2 mRNA expression occur independently of endoscopic or histologic signs of GERD in the acid-exposed squamous epithelium of the distal esophagus. However, this early COX-2 increase in GERD is further upregulated within the MDA sequence for yet unknown reasons.

Roles of thymidylate synthase and dihydropyrimidine dehydrogenase expression in blood as predictors of response to multimodal therapy in esophageal cancer

BACKGROUND Thymidylate synthetase (TS) and dihydropyrimidine dehydrogenase (DPD) RNA expression in peripheral blood was examined as a noninvasive molecular predictor of response to neoadjuvant radiochemotherapy in patients with locally advanced cancer of the esophagus. METHODS Blood samples were drawn from 29 patients with esophageal cancer (10 squamous cell carcinomas and 19 adenocarciomas) before neoadjuvant radiochemotherapy. After extraction of cellular tumor RNA from blood samples, quantitative expression analysis of TS and DPD was performed with quantitative real-time reverse-transcription polymerase chain reaction. RESULTS Twenty of 29 (68%) of patients had a minor histopathologic response, and 9 of 29 (32%) had a major response to neadjuvant radiochemotherapy. RNA expression in the blood of patients was detectable for TS in 86%, for DPD in 97%, and in 100% for β-actin. No significant associations were detected between TS and DPD expression levels and clinical variables of the patients. A high expression level for TS was associated with a minor response to neoadjuvant treatment (P = .046), while there was no significant association between DPD and response to therapy. Combined analysis of TS and DPD expression increased the specificity for the prediction of response to 100%. No major responder to therapy had high expression levels for both genes in their peripheral blood. CONCLUSION Quantitation of TS and DPD in peripheral blood may be a highly specific analysis to identify a subset of patients who do not respond to neoadjuvant radiochemotherapy and may therefore prevent expensive, noneffective, and potentially harmful therapies in a substantial number of patients with esophageal cancer.

miRNA expression profiles in high-grade prostatic intraepithelial neoplasia.

45 Background: High-grade prostatic intraepithelial neoplasia (HGPIN) is widely believed to be a precursor of prostate cancer (PCa). However, little is known about the expression of miRNAs variations in HGPIN compared to normal tissues and PCa. Methods: The expression data of 1054 miRNAs from TCGA were applied to identify relevant miRNAs associated with tumor progression (i.e., miR-98-5p, miR-183-5p, 345-5p, miR-143 miR-210-3p and miR-378-3p). miRNA were isolated by miRNeasy FFPE kit (Qiagen, Hilden, Germany) from paraffin-embedded tissues (FFPE) of prostate specimens with PCa, HGPIN and normal tissues. Early-stage PCa was defined as PCa with pT2 tumor stage, Gleason score <=7a (3+4) and PSA level <10 ng/ml. Quantitative miRNA expression data were acquired and analyzed using a real-time TaqMan-based PCR with the ABI Prism 7900HT (Life Technologies, Darmstadt, Germany). ANOVA analysis were performed to evaluate the expression of miRNAs between HGPIN, Normal and PCa tissues. All statistical analysis was per...

Die ansteigende Cyclooxygenase-2 Expression in der Metaplasie-Dysplasie-Karzinom Sequenz beim Barrett-Karzinom ist nicht assoziiert mit der inflammatorischen Umgebungsreaktion

Background: Epidemiological data assume a reduction of risk for developing an adenocarcinoma of the esophagus for individuals taking NSAIDs. One of the inhibited enzymes, cyclooxygenase-2, is supposed to be of major influence in the pathogenesis of Barrett’s cancer. We examined a possible association between COX-2 protein expression and the progressive severity within Barrett’s metaplasia-dysplasia-carcinoma sequence and the type and extent of the corresponding inflammatory reaction. Methods: COX-2 protein expression was examined in precurser lesions (metaplasia, low-grade-and high-grade-dysplasia) as well as tumor tissue of 49 resection specimens. Thereby interindividual variability was minimized. Immunohistochemical staining was graded on a scale 0–3 based on the percentage of specific tumor cell staining. Active and chronic inflammatory reaction was scored on a scale 0–3 as defined by the Updated Sydney Classification. Results: COX-2 expression is significant lower in squamous epithelium than in Barrett’s metaplasia (p < 0.001). Within Barrett’s metaplasia-dysplasia-carcinoma sequence a significant progressive increase in protein expression was noticed (Friedman test: p < 0.0001). Individual statistical testing detected the most significant differences between squamous epithelium and Barrett’s metaplasia (Wilcoxon test: p < 0.001) as well as between low-grade and high-grade dysplasia (Wilcoxon test: p < 0.0001). No association was present between COX-2 expression and pT-categories or grading of the tumor. Active and chronic inflammation were significantly different between squamous epithelium and Barrett’s metaplasia (Wilcoxon test: p < 0.0001) but not between Barrett’s metaplasia and carcinoma. Conclusions: There is a significant association between COX-2 protein expression and progression of the Barrett’s metaplasia-dysplasia-carcinoma sequence not explicable through changes in kind or intensity of the inflammatory reaction of the environment. Therefore, selective COX-2 inhibitors might be used as chemoprevention strategy independently of the inflammatory reaction.