Year: 2012
Type: conference-abstract
Abstract: AXL is a receptor tyrosine kinase (RTK) whose overexpression in vitro and in vivo facilitates tumor growth, invasion, and metastasis. Blockade of the AXL/gas6 pathway inhibits tumor growth in animal models. To date, the role of AXL in early-stage non–small cell lung cancer (NSCLC) is not known. During the period 2006–2009, we collected 127 resected NSCLC specimens from patients with Ia to IIIb tumor, 54 women and 73 men with a median age of 66.2 years (range, 43.2-81.7 years). Tissue microarrays with 1-mm cores from 3 separate areas of each tumor were prepared and stained with anti-AXL monoclonal antibody (R&D Systems) according to the manufacturer’s protocol. Immunohistochemical scoring was performed by an experienced pathologist on a 0 to 2 staining scale [negative, 0; intermediate, 1+; strong, 2+]. Endothelial cells were considered internal positive controls with intensity 2+. Of the tumors, 19 were AXL-negative (0), 52 were intermediate (1+), and 56 showed strong expression (2+). Independent of stage and tumor diameter, the 3-year relapse-free survival was 100% for the AXL-negative group, whereas it was 70.1% and 68.2% for the intermediate and strong expressing groups, respectively. Most relapses were systemic. We found no significant correlation between AXL expression and age, histology, or smoking history. To our knowledge, we are the first group to investigate the role of AXL expression in a large cohort of surgically resected NSCLCs coupled with clinical data. Absence of AXL expression seems to override the effect of tumor size and stage, with the risk of relapse increasing with AXL positivity. Since most relapses were systemic, AXL expression might be useful for identifying patients for adjuvant systemic therapy.
Institutions: Stanford Medicine, Stanford University
Language: English
Topic: Lung Cancer Research Studies
Subfield: Oncology
Field: Medicine
Domain: Health Sciences
Open Access status: bronze
OpenAlex ID: W2565080907