MIcroRNA expression profiling of chemotherapy resistant esophageal adeno- and squamous cell carcinoma cell lines
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ABSTRACT: Chemotherapy resistance adversely impacts the treatment of some individuals with esophageal cancer. Identifying chemotherapy resistance might help tailor clinical treatments. In this study the impact of microRNAs on chemotherapy resistance in esophageal cancer was investigated. We used microarrays to detail the global programme of microRNA expression underlying chemotherapy resistance and identified distinct classes of up-regulated microRNAs in generated chemotherapy resistant cell lines. An in-vitro model of acquired chemotherapy resistance in esophageal adeno- (EAC) and squamous cell carcinoma (SCC) cells was used, and microRNA expression profiles for cisplatin or 5-fluorouracil (FU) resistant variants vs. chemotherapy sensitive controls were compared using microarray. These results were further validated using qRT-PCR techniques (not shown in this submission).
Project description:This dataset was generated by RNA sequencing of whole tibiae of C57Bl/6 mice. For young mice; tibiae from 6-weeks-old mice were used and for aged mice tibiae from 70-weeks-old mice were used. The control, radiation, and chemotherapy samples were generated using 14-weeks-old mice. For radiation treatment; mice were exposed to sublethal irradiation while for chemotherapy samples mice were treated with carboplatin and tibiae were collected
Project description:Oesophageal cancer is the ninth most common cancer in the UK and accounts for 5% of all cancer deaths. The incidence of the disease in men has risen 50% in the last 25 years with the commonest pathological subtype in the West being adenocarcinoma, while in East Asia oesophageal squamous cell carcinoma predominates. Despite efforts to screen for Barrett’s oesophagus, and pre-operatively select OAC patients who are likely to benefit from potentially curative surgery, survival remains poor. The five year survival rate is less than 17% and even in early stage locoregional confined disease this figure lies between 25-35%. A significant improvement in overall survival has been demonstrated with neo-adjuvant or peri-operative chemotherapy but the optimal approach for individual patients remains unclear. A consistent finding has been that complete histopathological response to neo-adjuvant chemotherapy is a prognostic biomarker for increased survival benefit. Therefore, there is a pressing need to identify biomarkers capable of predicting response, enabling clinicians to select patients for whom neo-adjuvant therapies would be beneficial. This experiment represents gene expression profiling of 60 pre-treatment formalin-fixed paraffin embedded (FFPE) oesophageal adenocarcinoma biopsies. All patients were treated with neo-adjuvant cisplatin-based chemotherapy prior to surgical resection at the Northern Ireland Cancer Centre from 2004-2012. The aim of the experiment was to carry out functional enrichment of pathological responders and non-responders to neo-adjuvant chemotherapy in order to identify novel mechanism of drug resistance or chemo-sensitivity.
Project description:Background: Eosinophilic esophagitis (EoE) is a chronic non-IgE-mediated allergic disease of the esophagus. An unbiased proteomics approach was performed to investigate pathophysiological changes in esophageal epithelium. Additionally, an RNAseq-based transcriptomic analysis in paired samples was also carried out. Methods: Total proteins were purified from esophageal endoscopic biopsies in a cohort of adult EoE patients (n = 25) and healthy esophagus controls (n = 10). Differentially accumulated (DA) proteins in EoE patients compared to control tissues were characterized to identify altered biological processes and signaling pathways. Results were also compared with a quantitative proteome dataset of the human esophageal mucosa. Next, results were contrasted with those obtained after RNAseq analysis in paired samples. Finally, we matched up protein expression with two EoE-specific mRNA panels (EDP and Eso-EoE panel). Results: A total of 1667 proteins were identified, of which 363 were DA in EoE. RNA sequencing in paired samples identified 1993 differentially expressed (DE) genes. Total RNA and protein levels positively correlated, especially in DE mRNA-proteins pairs. Pathway analysis of these proteins in EoE showed alterations in immune and inflammatory responses for the upregulated proteins, and in epithelial differentiation, cornification and keratinization in those downregulated. Interestingly, a set of DA proteins, including eosinophil-related and secreted proteins, were not detected at the mRNA level. Protein expression positively correlated with EDP and Eso-EoE, and corresponded with the most abundant proteins of the human esophageal proteome. Conclusions: We unraveled for the first time key proteomic features involved in EoE pathogenesis. An integrative analysis of transcriptomic and proteomic datasets provides a deeper insight than transcriptomic alone into understanding complex disease mechanisms.
Project description:There is large variability among lung squamous cell carcinoma (SCC) patients in response to treatment with cisplatin based chemotherapy. LncRNAs is potentional a new type of predictive marker that can identify subgroups of patients who benefit from chemotherapy and it will have great value for treatment guidance. Differentially expressed LncRNAs were identified using microarray profiling of tumors with partial response (PR) vs. with progressive disease (PD) from advanced lung SCC patients treated with cisplatin based chemotherapy and validated by quantitative real-time PCR (qPCR). Results: Compared with the PD samples, 953 lncRNAs were consistently overregulated and 749 lncRNAs
Project description:Some neuroblastoma patients relapse after chemotherapy. Here, a Th-MYCNCPM32 mouse model usually have spontaneously tumours which are sensitive to chemotherapy. By treating mice with consecutive cycles of sublethal cyclophosphamide (CPM) using a personal dose escalation protocol (PDE), resistant tumours may develop. This experiment aims to compare the expression profiles (RNA-Seq) of sensitive and resistant MYCN driven tumours in order to understand the mechanisms behind resistance. Samples also presented cross-resistance to vincristine and doxorubicin.
Project description:Understanding the mechanism of resistance in platinum-based regimens for the treatment of high-grade serous ovarian cancer (HGSOC) is important for identifying new therapeutic targets to improve the clinical outcome of ovarian cancer patients. Mass spectrometry-based proteomic strategy was applied to spheroidal cisplatin sensitive and resistant HGSOC generated cell lines in the absence and presence of cisplatin drug. A complete expressed HGSOC proteome and phosphoproteome was characterized in cisplatin sensitive and resistant HGSOC cell lines providing insight into the mechanism of resistance development. PCA analysis showed that phosphorylation of a few proteins provides better classification than the whole proteome of the cellular subtypes. Specifically, a distinctive phosphoproteomic signature between cisplatin sensitive and resistant cell lines in the absence of drug was observed. This same phosphoproteomic signature was observed in our cisplatin sensitive cell line in the absence and presence of drug, indicating a vital role for phosphorylation of proteins in resistance development to cisplatin. The most phosphorylated protein was sequestosome (p62/SQSTM1). Differential expressions of apoptosis by the prognostic factor ratio of Bcl-2/Bax and autophagy, known to be regulated by p62/SQSTM1, was validated in the proteome data and by western blot analysis. A significant increase in apoptosis in the presence of cisplatin was observed in only the sensitive cell line while autophagy revealed increased expression in the resistant relative to sensitive cell line. Furthermore, site specific phosphorylation on 20 modified residues of sequestosome was characterized. Elevated expression of phosphorylation of sequestosome in resistant HGSOC cell lines was validated with western blot analysis. Here, we propose phosphorylation of sequestosome to be a marker and key in cisplatin resistance development in HGOSC ovarian cancers by shuttling ubiquitinated proteins to the autophagy pathway and influencing down-regulation of apoptosis.
Project description:In patients with advanced colorectal cancer, leucovorin, fluorouracil, and irinotecan (FOLFIRI) is considered as one of the reference first-line treatments. However, only about half of treated patients respond to this regimen, and there is no clinically useful marker that predicts response. A major clinical challenge is to identify the subset of patients who could benefit from this chemotherapy. We aimed to identify a gene expression profile in primary colon cancer tissue that could predict chemotherapy response. Patients and Methods:- Tumor colon samples from 21 patients with advanced colorectal cancer were analyzed for gene expression profiling using Human Genome GeneChip arrays U133. At the end of the first-line treatment, the best observed response, according to WHO criteria, was used to define the responders and nonresponders. Discriminatory genes were first selected by the significance analysis of microarrays algorithm and the area under the receiver operating characteristic curve. A predictor classifier was then constructed using support vector machines. Finally, leave-one-out cross validation was used to estimate the performance and the accuracy of the output class prediction rule. Results:- We determined a set of 14 predictor genes of response to FOLFIRI. Nine of nine responders (100% specificity) and 11 of 12 nonresponders (92% sensitivity) were classified correctly, for an overall accuracy of 95%. Conclusion:- After validation in an independent cohort of patients, our gene signature could be used as a decision tool to assist oncologists in selecting colorectal cancer patients who could benefit from FOLFIRI chemotherapy, both in the adjuvant and the first-line metastatic setting. All tissue samples were maintained at −180°C (liquid nitrogen) until RNA extraction and were weighed before homogenization. Tissue samples were then disrupted directly into a lysis buffer using Mixer Mill MM 300 (Qiagen, Valencia, CA). Total RNA was isolated from tissue lysates using the RNeasy Mini Kit (Qiagen), and additional DNAse digestion was performed on all samples during the extraction process (RNase-Free DNase Set Protocol for DNase treatment on RNeasy Mini Spin Columns; Qiagen). After each extraction, a small fraction of the total RNA preparation was taken to determine the quality of the sample and the yield of total RNA. Controls analyses were performed by UV spectroscopy and analysis of total RNA profile using the Agilent RNA 6000 Nano LabChip Kit with the Agilent 2100 Bioanalyser (Agilent Technologies, Palo Alto, CA) to determine RNA purity, quantity, and integrity.
Project description:Preoperative chemoradiotherapy (CRT) followed by surgery has been proved to improve esophageal squamous cell carcinoma (ESCC) patientsM-bM-^@M-^Y survival in comparison with surgery alone. However, the outcomes of CRT are heterogeneous, and no clinical or pathological method could predict CRT response. We aim to identify mRNA markers for ESCC CRT-response prediction through gene expression analyses. Gene expression analyses were performed on pretreatment cancer biopsies from 28 ESCCs who received neoadjuvant CRT and surgery and 10 normal esophageal epithelia using Affymetrix U133 Plus 2.0 arrays.
Project description:Non Small Cell Lung Cancer (NSCLC) causes the premature death of over 1 million people worldwide each year, but remains inadequately understood at the molecular level. To provide new insights for NSCLC treatment we performed a molecular characterisation of wild type and platinum drugs resistance in A549 cells. Transcriptome profiling revealed contrasting patterns of gene expression in sensitive and resistant cells and identified genes whose expression was highly correlated with the platinum drugs. Our results revealed a gene set of 15 transcripts whose expression was highly correlated with platinum-resistance in NSCLC A549 cell lines.
Project description:Chemotherapy resistance adversely impacts the treatment of some individuals with esophageal cancer. Identifying chemotherapy resistance might help tailor clinical treatments. In this study the impact of microRNAs on chemotherapy resistance in esophageal cancer was investigated. We used microarrays to detail the global programme of microRNA expression underlying chemotherapy resistance and identified distinct classes of up-regulated microRNAs in generated chemotherapy resistant cell lines.