An Invasive Gene Expression Signature in Pancreas Cancer

Gene expression profiling has demonstrated clinical utility as a predictive tool in clinical oncology. We have identified genes associated with invasion of pancreatic cancer, and with potential for identifying early recurrence. We used Affymetrix Human U133 Plus 2.0 microarrays to identifiy specific predictive profiles in pancreatic cancer, and the evolution of gene expression. We identified distinct classes of up-regulated genes during this process. Primary and metastatic pancreatic cancer cell lines (BxPC-3 and AsPC-1), were stimulated with with phorbol-12-myristate 13-acetate (PMA), a known inducer of invasion. Affymetrix gene expression microarray analysis was performed, comparing PMA stimulated BxPC-3 and AsPC-1 gene expression to unstimulated controls, and also PMA stimulated BxPC-3 verses stimulated AsPC-1 cell lines. Differential gene expression was identified using ArrayAssist bioinformatics software. Gene expression changes were confirmed using quantitative reverse transcription polymerase chain reaction (qRT-PCR) (Assays-on-demand, Taqman, ABI systems). Pathway Assist and GOstat were used to identify pathway and gene ontology changes.

基因表达谱分析在临床肿瘤学领域已被证实可作为预测工具，具备临床实用价值。本研究已鉴定出与胰腺癌侵袭相关、且具备早期复发识别潜力的基因。我们采用Affymetrix Human U133 Plus 2.0基因芯片，旨在鉴定胰腺癌的特异性预测特征以及基因表达的动态演化过程，并在此过程中识别出不同类别的上调基因。我们将原代胰腺癌细胞系与转移性胰腺癌细胞系（BxPC-3及AsPC-1）用佛波醇-12-肉豆蔻酸酯-13-乙酸酯（PMA，一种公认的侵袭诱导剂）进行刺激，随后开展Affymetrix基因表达芯片分析：将PMA刺激后的BxPC-3与AsPC-1细胞的基因表达水平与未刺激对照组进行对比，同时比较PMA刺激后的BxPC-3与AsPC-1细胞系的基因表达差异。研究人员借助ArrayAssist生物信息学软件鉴定出差异表达基因，并通过定量反转录聚合酶链式反应（qRT-PCR，涵盖Assays-on-demand检测试剂盒、Taqman技术及ABI系统相关配套方案）验证了基因表达的变化。此外，本研究采用Pathway Assist与GOstat工具，分别对信号通路及基因本体（Gene Ontology, GO）的变化进行分析鉴定。