Project description:Recently we had discovered a solid cord like structure at the limbus of human eyes, termed as the Limbal Epithelial Crypt (LEC). It arises from the undersurface of the interpalisade rete ridges and extends towards the conjunctiva over the conjunctival stroma. Anatomical and immunohistochemical studies have shown it to be potentially a Stem Cell Niche. To confirm this hypothesis we conducted comparative gene expression profile of LEC with pathway and Geneontology studies in comparison with other ocular surface epithelial regions such as cornea, limbus, LEC stroma and conjunctiva. Frozen tissue blocks of corneoscleral buttons dissected from cadaver eyes were cryosectioned. These tissue sections from different ocular surface regions were laser microdissected. Extracted RNA was amplified & hybridized to 30,000k Human spotted cDNA microarray chips. Raw data obtained with Genepix Pro6 software was filtered, normalized & analysed on BASE & Jexpresspro software. Unpaired T-Test, Significance Analysis of Microarrays were performed on the data. Database for Annotation, Visualisation, and Integrated Discovery (DAVID) (http://www.DAVID.niaid.nih.gov) and Ingenuity Pathway Analysis (IPA) was used to determine the enriched GO terms and pathways in the differentially expressed genes. Quantitative gene expression analysis (qPCR) and immunohistochemistry was performed on the genes of interest. Statistical analysis for real time PCR was performed on SPSS16 to determine the normalised expression of gene of interest on ocular surface regions. Samples were prepared from five human ocular surface epithelial regions such as Cornea, Limbus, LEC, LEC Stroma, Conjunctiva. There were four replicates in each groups except Cornea and Conjunctiva with 3 each. The Standard Probe (SP) was prepared from mixing equal amount of Corneal and conjunctival epithelial RNA followed by ethanol precipitation. Samples were labelled with Cy5 dye and Standard Probe with Cy3 Dye. These were mixed in equal amount to prepare hybrid probes which were then hybridised to microarray slide.

Project description:Background The dramatic increase in incidence of ductal carcinoma in situ (DCIS) associated with mammographic screening for breast cancer has given emphasis to the challenges of managing this important clinical entity. Unlike invasive breast cancer, there is no established histopathologic grading system for DCIS, nor are there biological markers of prognosis to guide clinical management. The aim of this study is to use molecular profiling to identify robust and clinically applicable indicators of DCIS malignant potential. Methods Areas of intraduct carcinoma, atypical ductal hyperplasia and benign epithelium were isolated from 46 well-characterised invasive breast cancers by laser capture microdissection. Microarray based gene expression profiling was used to identify genes differentially expressed between DCIS associated with grade 1 and grade 3 invasive carcinoma (‘grade associated genes’). The expression profile of these genes was then determined in all samples and used to define ‘molecular grade’ categories. The genomic basis of gene expression derived categories was examined by array-based comparative genomic hybridisation (CGH). Results DCIS samples could be divided into two subgroups, designated low and high molecular grade (MG) on the basis of expression at 173 grade associated oligonucleotide probes. The low MG subgroup included 21 DCIS samples of low (n=10) and intermediate (n=11) nuclear grade as well as all samples of ADH (n=4) and benign epithelium (n=7). The high MG subgroup included 27 DCIS samples of intermediate (n=7) and high (n=19) nuclear grade. Array CGH revealed distinct differences in the character and degree of genomic aberration associated with MG and the clinical significance of MG was verified by a strong correlation with survival in two independent invasive breast cancer gene expression datasets (n=295 and n=186). MG categories were strongly associated with histopathologic and biomarker features of DCIS. Using a classification tree model, DCIS MG could be accurately predicted in 44/46 (95.7%) of samples using a combination of nuclear grade and Ki67 score. Conclusions Molecular profiling indicates a binary grading scheme for DCIS that is both biologically relevant and clinically informative. The low and high MG DCIS classification could be recapitulated by a novel combination of routinely accessible features. This practical approach has potential to immediately improve clinical evaluation and management of DCIS. Keywords: Paired gene expression and CGH Paired CGH and Gene Expression on DCIS of the breast

Project description:Specific deletion of Tgfbr2 in FSP1+ fibroblasts (Tgfbr2fspKO) induced development of SCC in forestomach with 100% penetrance. Tgfbr2fspKO mice die by 7 weeks with a median survival of 38 days (Log rank p<0.001). Examination of Tgfbr2fspKO forestomach between embryonic day 16 (E16) and 5 weeks of age suggested that hyperplasia began during week 3 and was followed by dysplasia, carcinoma in situ, and invasive squamous cell carcinoma (SCC). The aim of this study was to elucidate genetic aberrations in the tumor associated stroma and SCC tumor using array comparative genomic hybridization (CGH) analysis. Laser capture micro-dissection was performed using formalin-fixed, paraffin-embedded, 5 week old Tgfbr2fspKO forestomach tissues. Genetic loss of cyclin-dependent kinase inhibitor, Cdkn2a/ p16Ink4A was found in laser captured epithelia of all three Tgfbr2fspKO forestomachs. Surprisingly, no genetic change was seen in the tumor associated stroma. Examination of human esophageal SCC showed a down-regulation of TGFβ receptor 2 (TβRII) in the stromal fibroblasts as well as increased inflammation and DNA damage. Published literature showed that loss of Cdkn2a/p16Ink4A tumor suppressor is the common event in human ESCCs. Our study suggests anti-inflammation may be a new therapeutic option in treating human SCCs with down-regulation of TβRII in the stroma. Laser capture microdissection of Tgfbr2flox/flox (n=3) and Tgfbr2fspKO (n=3) forestomach tissues was performed using an Arcturus XT (Life Technologies, CA, USA). Mouse background strain is C57Bl6. Frozen tissue sections on PEN membrane frame slides (Applied Biosystems) were H&E stained followed by dehydration using the standard protocol to improve visualization of the cells at the microscope. The epithelia and stroma were identified by morphology, captured using a low-power infrared laser pulse, and transferred onto a cap (Capsure™ Macro LCM Caps, Life Technologies). The DNA was extracted using a QIAamp DNA micro kit (Qiagen, CA, USA). Array-CGH was performed using test DNA from laser captured epithelia and stroma from Tgfbr2fspKO mice. Reference DNA was laser captured from the epithelia of normal forestomach of Tgfbr2flox/flox mice. DNA was labeled with Cy3 (test) or Cy5 (control) fluorescent dyes (Perkin Elmer, MA, USA) according to the BioPrime array CGH genomic labeling protocol (Invitrogen, Carlsbad, CA) and cleaned using Microcon YM-30 filters (Millipore, Billerica, MA). Hybridization was carried out using Mouse Genome CGH Microarray 4x180 K format from Agilent Technologies (Santa Clara, CA) according to CGH Procedures for Genomic DNA Analysis (Agilent Technologies). Slides were hybridized for 20 hours, washed, and scanned with an Agilent microarray scanner. Data was analyzed using Feature Extraction® and CGH Analytics® software packages (Agilent Technologies).

Project description:Introduction: Targeting of the tumor vasculature has evolved into an integral part of existing standard anti-cancer therapies. However, recent pre-clinical and clinical studies have shown that the efficacy of these treatments is temporary at most and frequently followed by the renewed tumor growth, indicating that these targets may not be robust. Methods: We transcriptionally profiled laser capture microdissection isolated microvessels from tumor and matching adjacent normal tissue samples obtained from breast cancer patients diagnosed with infiltrating ductal carcinoma. Gene expression profiles were generated and analyzed using Genespring and the web-based WebGestalt bioinformatics Toolkit. Several differentially expressed genes were validated by immunohistochemistry. To further mine our data set we used a novel integrative systems biology network approach to identify a gene signature that could robustly stratify breast cancer patient populations. Results: Vascular enrichment of the LCM samples was confirmed by Q-PCR of CD31. Hierarchical two-dimensional clustering of the transcriptome data identified 219 significantly upregulated transcripts in at least 4/8 patient samples (cut-off >1.3-fold, p<0.05). Several genes AGRN, FLNA and ILR4 were selected and their protein overexpression was confirmed in the tumor tissue. Additional mining of the data set using the clinical information associated with these tissues by applying an integrative bioinformatics network method generated a 15-gene M-bM-^@M-^XVascular-Derived Prognostic PredictorM-bM-^@M-^Y that is able to stratify patient populations in to high- and low- risk groups. Conclusions: The overall heterogeneity observed in the vascular gene expression patterns in the infiltrating ductal carcinoma samples poses a significant problem for these individual genes to be used as a robust vascular breast cancer specific marker or therapeutic target. Using an integrative bioinformatics network approach allowed us to identify a 15-gene M-bM-^@M-^XVascular-Derived Prognostic PredictorM-bM-^@M-^Y that can robustly identify patients with an increased risk of local recurrence. Stratifying patient populations using this gene signature may lead to better patient-tailored treatment regimes. Two-color microarrays comparing laser-captured microvessels from the tumors and matching adjacent normal tissues of 8 breast cancer patients

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