Author of

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  P2.04 - Poster Session 2 - Tumor Immunology (ID 154)

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

  • 11513

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    P2.04-002 - Differential expression of PD-L1, PD1 and CTLA4 receptor according to histology and tumour vs. surrounding non-malignant lung tissue in non-small cell lung cancer: RNA sequencing data (ID 2427)

    10:30 - 11:30  |  Author(s): K. Reynders
    • Abstract

    Background
    Immune modulatory strategies directed against CTLA4 (Cytotoxic T-Lymphocyte Antigen 4), PD1(Programmed cell Death 1) and PD-L1 (Programmed cell Death 1 Ligand 1) either in monotherapy or in combination with chemotherapy and radiotherapy offer great promise as novel treatments against lung cancer. Its outcome and therapeutic ratio may depend on the expression of the target molecules in tumours and the surrounding non-malignant lung tissue. We here report the expression of CTLA4, PD1 and PD-L1 in primary resected NSCLC and in the surrounding non-malignant lung.

    Methods
    RNA sequencing was performed on tumor tissue and normal lung tissue from resection specimens of NSCLC patients. The association between CTLA4, PD1 and PD-L1 expression levels and histology, gender, age, smoking status (current smoker vs. smoking cessation of at least one year), COPD and CRP blood levels was calculated both in the primary tumour and the normal lung. Results are expressed as mean +/- SD and range. Means were compared using Wilcoxon’s signed rank test for the distributions were non-parametrical. P-values <0.05 were considered significant.

    Results
    Fourteen patients were studied, 11 males and 3 females, with a mean age of 64.6 +/- 10.0 years (41-79). All patients had a smoking history: 6 were current smokers, 8 former smokers. COPD status: 8 no COPD, 1 GOLD class I, 3 GOLD class II, 2 GOLD class III. Pre-operative CRP (mg/dL): 15.0 +/- 2.9 (0.20-54.7). Seven patients had squamous cell cancer, 7 adenocarcinoma. PD-L1 expression in the lung was 3833 +/- 787 (372-5072), PD-L1 in the tumour 2595 +/- 1657 (788-6689), with a tumour/lung ratio of 0.67 +/- 0.37 (0.21-1.32). PD-L1 squamous vs. adenocarcinoma was 1840 +/- 1012 vs. 3350 +/- 1896, p<0.001. PD-L1 in the lung of ex-smokers vs. current smokers: 4136 +/- 811 vs. 3430 ± 591, p<0.001. These associations were not found for CTLA4 and PD1 receptor: CTLA4 tumour squamous vs. adenocarcinoma: 100.9 +/- 46.3 vs. 95.3 +/- 73.6, p=0.86; CTLA4 lung smokers vs. ex-smokers: 78.4 +/- 41.3 vs. 107.0 +/- 75.1, p=0.75. PD1 receptor tumour squamous vs. adenocarcinoma: 591 +/- 244 vs. 689 +/- 263, p=0.31 PD1 receptor in the lung of smokers vs. ex-smokers: 599 +/- 278 vs. 695 +/-216, p=0.46. No associations between CTLA4, PD1 and PD-L1 in the tumour or the lung and gender, age, COPD and CRP blood levels were found.

    Conclusion
    RNA sequencing is a useful method to dissect relevant molecules in the tumour and the lungs. Our results show more PD-L1 expression in adenocarcinoma than in squamous cell cancer, more PD-L1 expression in the non-malignant lung of ex-smokers than in current smokers and reduced PD-L1 in tumours compared to adjacent lung tissue.