25P - Autophagy in early stage NSCLC – prognostic significance of the autophagy markers p62 and LC3B

Date 15 April 2016
Event European Lung Cancer Conference 2016 (ELCC) 2016
Session Poster lunch
Topics Non-small-cell lung cancer
Translational Research
Basic Principles in the Management and Treatment (of cancer)
Presenter Sabina Berezowska
Citation Journal of Thoracic Oncology (2016) 11 (supplement 4): S57-S166. S1556-0864(16)X0004-4
Authors S. Berezowska1, A.M. Schläfli1, O. Adams1, J.A. Galván1, L. Bubendorf2, S. Savic Prince2, R.A. Schmid3, M. Gugger4, M.P. Tschan1, R. Langer1
  • 1Experimental And Clinical Pathology, Institute Of Pathology, University of Bern, 3010 - Bern/CH
  • 2Institute Of Pathology, Institute of Pathology-University Hospital Basel, 4031 - Basel/CH
  • 3Division Of General Thoracic Surgery, Inselspital Bern, Bern/CH
  • 4Pathology, promed, Laboratoire médicale, 1723 - Bern/CH

Abstract

Background

In cancer, autophagy may promote tumor cell survival or cell death. Protein light chain 3B (LC3B) and p62 are proteins associated with autophagosomal membranes that engulf cytoplasmic content during autophagy, which is subsequently degraded. We studied the expression of these two markers in stage I/II non-small cell lung cancer (NSCLC).

Methods

Immunohistochemistry for LC3B and p62 was performed on a tissue microarray with 466 NSCLC: 202 Adenocarcinomas (AC), 220 squamous cell carcinomas (SCC), 35 large cell carcinomas. Dot-like cytoplasmic expression of LC3B and dot-like, cytoplasmic and nuclear staining for p62 was determined. Results were compared with clinical and pathological parameters.

Results

LC3B expression correlated with all p62 staining patterns, as those correlated among each other (x2

Conclusions

The autophagy markers LC3B and p62 are differentially expressed in NSCLC, pointing towards a biologically significant role in these tumors. High LC3B levels seem to be linked to lower tumor aggressiveness, while high general p62 expression was significantly associated with aggressive tumor behavior. Interestingly, p62 cytoplasmic/nuclear expression – which may not be linked to autophagy such as the dot-like pattern – had the highest prognostic value. Our results warrant further investigations concerning the link between expression data and functional autophagy states and a non-autophagy related role of p62 in NSCLC.

Clinical trial identification

Legal entity responsible for the study

Kantonale Ethikkomission Bern

Funding

Bernische Krebsliga

Disclosure

All authors have declared no conflicts of interest.