Article

Generation of a non-small cell lung cancer transcriptome microarray.

Almac Diagnostics Ltd, 19 Seagoe Industrial Estate, Craigavon, BT63 5QD, UK.
BMC Medical Genomics (Impact Factor: 3.47). 02/2008; 1:20. DOI:10.1186/1755-8794-1-20
Source: PubMed

ABSTRACT Non-small cell lung cancer (NSCLC) is the leading cause of cancer mortality worldwide. At present no reliable biomarkers are available to guide the management of this condition. Microarray technology may allow appropriate biomarkers to be identified but present platforms are lacking disease focus and are thus likely to miss potentially vital information contained in patient tissue samples.
A combination of large-scale in-house sequencing, gene expression profiling and public sequence and gene expression data mining were used to characterise the transcriptome of NSCLC and the data used to generate a disease-focused microarray - the Lung Cancer DSA research tool.
Built on the Affymetrix GeneChip platform, the Lung Cancer DSA research tool allows for interrogation of ~60,000 transcripts relevant to Lung Cancer, tens of thousands of which are unavailable on leading commercial microarrays.
We have developed the first high-density disease specific transcriptome microarray. We present the array design process and the results of experiments carried out to demonstrate the array's utility. This approach serves as a template for the development of other disease transcriptome microarrays, including non-neoplastic diseases.

0 0
 · 
0 Bookmarks
 · 
82 Views
  • [show abstract] [hide abstract]
    ABSTRACT: Distant metastasis is one of the leading causes of lung cancer death. Detecting the early-stage molecular alternations in primary tumors, such as gene expression differences, provides a "prognostic" value to the precaution of tumor metastasis. The aim of this article is to screen and identify the metastasis-related genes in human squamous cell lung carcinoma. Primary tumor tissues of nine patients with subsequent metastasis and eight patients without metastasis were selected to perform the gene microarray experiment. GO and pathway analyses were used to determine the differentially expressed genes. Two identified genes were further validated by real-time quantitative reverse transcription polymerase chain reaction (PCR) (real-time qRT-PCR). Two hundred and thirty-eight differentially expressed genes were detected in gene chip experiment, including 51 up-regulated genes and 187 down-regulated genes. These genes were involved in several cellular processes, including cell adhesion, cell cycle regulation, and apoptosis. GO analysis showed that the differentially expressed genes participated in a wide ranging of metastasis-related processes, including extracellular region and regulation of liquid surface tension. In addition, pathway analysis demonstrated that the differentially expressed genes were enriched in pathways related to cell cycle and Wnt signaling. Real-time qRT-PCR validation experiment of LCN2 and PDZK1IP1 showed a consistent up-regulation in the metastasis group. The metastasis of human squamous cell lung carcinoma is a complex process that is regulated by multiple gene alternations on the expression levels. The 238 differentially expressed genes identified in this study presumably contain a core set of genes involved in tumor metastasis. The real-time qRT-PCR results of PDZK1IP1 and LCN2 validated the reliability of this gene microarray experiment.
    The Anatomical Record Advances in Integrative Anatomy and Evolutionary Biology 03/2012; 295(5):748-57. · 1.34 Impact Factor
  • Source
    [show abstract] [hide abstract]
    ABSTRACT: Gene expression profiling could assist in revealing biomarkers of lung cancer prognosis and progression. The handling of biological samples may strongly influence global gene expression, a fact that has not been addressed in many studies. We sought to investigate the changes in gene expression that may occur as a result of sample processing time and conditions. Using Illumina Human WG-6 arrays, we quantified gene expression in lung carcinoma samples from six patients obtained at chest opening before and immediately after lung resection with storage in RNAlater [T1a((CO)) and T1b((LR))], after receipt of the sample for histopathology, placed in RNAlater [T2a((HP))]; snap frozen [T2b((HP.SF))]; or snap frozen and stored for 1 week [T2c((HP.SFA))], as well as formalin-fixed, paraffin-embedded (FFPE) block samples. Sampling immediately after resection closely represented the tissue obtained in situ, with only 1% of genes differing more than twofold [T1a((CO)) versus T1b((LR))]. Delaying tissue harvest for an average of 30 minutes from the operating theater had a significant impact on gene expression, with approximately 25% of genes differing between T1a((CO)) and T2a((HP)). Many genes previously identified as lung cancer biomarkers were altered during this period. Examination of FFPE specimens showed minimal correlation with fresh samples. This study shows that tissue collection immediately after lung resection with conservation in RNAlater is an optimal strategy for gene expression profiling.
    The Journal of molecular diagnostics: JMD 03/2012; 14(2):140-8. · 3.48 Impact Factor
  • Source
    [show abstract] [hide abstract]
    ABSTRACT: There is no method routinely used to predict response to anthracycline and cyclophosphamide-based chemotherapy in the clinic; therefore patients often receive treatment for breast cancer with no benefit. Loss of the Fanconi anemia/BRCA (FA/BRCA) DNA damage response (DDR) pathway occurs in approximately 25% of breast cancer patients through several mechanisms and results in sensitization to DNA-damaging agents. The aim of this study was to develop an assay to detect DDR-deficient tumors associated with loss of the FA/BRCA pathway, for the purpose of treatment selection. DNA microarray data from 21 FA patients and 11 control subjects were analyzed to identify genetic processes associated with a deficiency in DDR. Unsupervised hierarchical clustering was then performed using 60 BRCA1/2 mutant and 47 sporadic tumor samples, and a molecular subgroup was identified that was defined by the molecular processes represented within FA patients. A 44-gene microarray-based assay (the DDR deficiency assay) was developed to prospectively identify this subgroup from formalin-fixed, paraffin-embedded samples. All statistical tests were two-sided. In a publicly available independent cohort of 203 patients, the assay predicted complete pathologic response vs residual disease after neoadjuvant DNA-damaging chemotherapy (5-fluorouracil, anthracycline, and cyclophosphamide) with an odds ratio of 3.96 (95% confidence interval [Cl] =1.67 to 9.41; P = .002). In a new independent cohort of 191 breast cancer patients treated with adjuvant 5-fluorouracil, epirubicin, and cyclophosphamide, a positive assay result predicted 5-year relapse-free survival with a hazard ratio of 0.37 (95% Cl = 0.15 to 0.88; P = .03) compared with the assay negative population. A formalin-fixed, paraffin-embedded tissue-based assay has been developed and independently validated as a predictor of response and prognosis after anthracycline/cyclophosphamide-based chemotherapy in the neoadjuvant and adjuvant settings. These findings warrant further validation in a prospective clinical study.
    CancerSpectrum Knowledge Environment 01/2014; 106(1):djt335. · 14.07 Impact Factor

Full-text (2 Sources)

View
16 Downloads
Available from
Nov 5, 2012