Author of

• 11543

  +

  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

  • 11561

    +

    P2.06-018 - Correlation of TS mRNA expression level and TS protein level detected by immunostaining for use in post-operative primary lung cancer therapy (ID 1697)

    09:30 - 09:30  |  Author(s): H. Dejima
    • Abstract

    Background
    There has been a focus on the use of thymidylate synthase (TS) as a biomarker for the long term administration of metabolic antagonists for lung cancer. TS mRNA levels have been measured by real time RT-PCR in tumors collected using a micro-dissection method; however, this method has not been applicable for general use and its clinical use has been problematic. Therefore, this study investigated the correlation of TS mRNA expression level and a commonly used semiquantitative immunohistochemical method.

    Methods
    Resected lung specimens were collected from 47 patients with Stage IA (T1b) and IIB primary non-small-cell lung cancer who had undergone lobectomy between 2006 and 2012 at our Hospital. Levels of mRNA expression were measured using the Danenberg Tumor Profile method while TS immunostaining with anti-TS mouse IgG MoAB was graded into 4 levels.

    Results
    Of 47 patients, 24 patients were male and 23 patients were female. Thirty six people had adenocarcinoma while 11 patients exhibited squamous cell carcinoma. The number of patients at each IA, IB, IIA and IIB stage were 20, 20, 5, and 2, respectively. TS mRNA expression levels of these patients were between 0.69 and 12.68 (a median value of 2.47). Immunostaining indicated that Grade 0, 1, 2, and 3 were observed in 3, 17, 15 and 12, respectively. A moderate positive correlation was observed at a correlation coefficient of r=0.4880 between mRNA expression levels and immunostain levels (A). Moreover, a significant correlation between mRNA expression levels and immunostain levels was observed when mRNA expression levels were divided into two groups, one with higher than median values and the other with lower than median values, where Grade 0 and 1 were assigned as negatively stained and Grade 2 and 3 were assigned as positively stained (B).Figure 1

    Conclusion
    Immunostaining is a useful method for measuring TS level when TS is being considered as an appropriate biomarker for postoperative adjuvant chemotherapy with 5-FU delivertives.