Author of

• 11543

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  P2.06 - Poster Session 2 - Prognostic and Predictive Biomarkers (ID 165)

  • Event: WCLC 2013
  • Type: Poster Session
  • Track: Biology
  • Presentations: 1
  • Moderators:
  • Coordinates: 10/29/2013, 09:30 - 16:30, Exhibit Hall, Ground Level

  • 11560

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    P2.06-017 - Long non coding RNAs (lncRNAs) are dysregulated in malignant pleural mesothelioma (MPM) (ID 1524)

    09:30 - 09:30  |  Author(s): K. Schelch
    • Abstract

    Background
    Malignant Pleural Mesothelioma (MPM) is an aggressive disease, often diagnosed at an advanced stage. It is characterized by a long latency period and prior asbestos exposure. Currently accurate diagnosis of MPM is difficult due to the lack of sensitive biomarkers, and despite minor improvements in treatment, median survival rates rarely exceed 12 months. Accumulating evidence suggests that aberrant expression of long non-coding RNAs (lncRNAs) plays an important functional role in cancer biology. LncRNAs are a class of recently discovered non-protein coding RNAs >200 nucleotides in length with a role in regulating transcription. The aims of this study were to characterize the expression and function of these lncRNAs in MPM.

    Methods
    To identify novel lncRNAs involved in MPM, microarray profiling was performed on five cell lines - the immortalized normal mesothelial cell line (MeT-5A) and four MPM lines (two epithelioid H28 and H226 and two biphasic MM05 and MSTO) using Invitrogen’s NCode lncRNA microarrays. These allow simultaneous assessment of mRNA and lncRNA content. High priority candidate lncRNAs were selected on the basis of statistical (P<0.05) and biological (>3-fold difference) significance. Expression of high priority candidates were technically validated using RT-qPCR, and biologically validated in three independent test sets. Pathway analyses were performed to interrogate the relationship between lncRNA and mRNA expression. Cell proliferation and colony formation assays were used to investigate lncRNA function.

    Results
    Microarray profiling and real-time qPCR validation identified 9 lncRNA candidates with significant differential expression in MPM compared with normal mesothelial cells Validation in three independent test sets by RT-qPCR analysis demonstrated consistent up-regulation of four of these lncRNAs. Receiver Operating Curve analysis showed that two of these candidates were able to separate benign pleura and MPM with high sensitivity and specificity. In addition, high expression of AK054908 was associated with nodal metastases with lower levels of AK130275 and AF268386 observed in patients receiving induction chemotherapy. Cases with higher EF177379 levels also demonstrated a trend to improved survival. The majority of mRNAs co-expressed with candidate lncRNAs were associated with cellular and metabolic processes including cell cycle, cell death and apoptosis. In functional studies, siRNA knockdown of AK130275 showed suppression of cell growth and colony formation in MPM cells with moderate changes observed following knockdown of EF177379.

    Conclusion
    To our knowledge this is the first systematic study of lncRNA expression profiles in MPM. We have found that lncRNA expression profiles can distinguish malignant mesothelium from normal pleural tissue, and that some lncRNAs are associated with nodal metastasis and long term survival. We also demonstrate that lncRNAs have potential prognostic and diagnostic utility with functional roles in regulating cell growth. Further work is required to evaluate whether these lncRNAs are capable of differentiating mesothelioma from lung cancer and benign asbestos-related diseases, and to reveal their specific functions in MPM pathogenesis.