Significance of tumour cell HLA-G5/-G6 isoform expression in discrimination for adenocarcinoma from squamous cell carcinoma in lung cancer patients.

Abstract

Human leucocyte antigen (HLA)-G has seven isoforms, of which HLA-G1-G4 are membrane-bound and HLA-G5-G7 are soluble. Previous studies reinforced HLA-G expression was strongly related to poor prognosis in different types of cancers. Among these studies, the monoclonal antibody (mAb) 4H84 was used which detects all HLA-G isoform heavy chain; unfortunately, leaves the specific types of isoforms expressed in lesions undistinguished and its clinical significance needs to be clarified. To explore clinical significance of lesion soluble HLA-G (sHLA-G) in non-small-cell lung cancer (NSCLC), mAb 5A6G7 recognizing HLA-G5/-G6 molecules was used. Tumour cell sHLA-G expression in 131 primary NSCLC lesions (66 squamous cell carcinoma, 55 adenocarcinoma and 10 adenosquamous carcinoma) were analysed with immunohistochemistry. Data showed that sHLA-G expression was observed in 34.0% (45/131) of the NSCLC lesions, which was unrelated to patient age, sex, lymph nodal status, tumour-node-metastasis stage and patient survival. However, tumour cell sHLA-G expression in lesions was predominately observed in adenocarcinoma lesions (73.0%, 40/55) which was significantly higher than that in squamous cell carcinoma (6.0%, 4/66) and adenosquamous carcinoma lesions (10.0%, 1/10, P < 0.001). The area under the receiver operating characteristic curve for lesion sHLA-G was 0.833 (95% CI: 0.754-0.912, P < 0.001) for adenocarcinoma versus squamous cell carcinoma. Our findings for the first time showed that tumour cell sHLA-G was predominately expressed in lung adenocarcinoma, which could be a useful biomarker to discriminate adenocarcinoma from squamous cell carcinoma in NSCLC patients.

• Authors: Wei-Hua Yan, Di Liu, Hai-Yan Lu, Ying-Ying Li, Xia Zhang, Aifen Lin
• Journal: Journal of cellular and molecular medicine (J Cell Mol Med) Vol. 19 Issue 4 Pg. 778-85 (Apr 2015) ISSN: 1582-4934 [Electronic] England
• PMID: 25689063 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: © 2015 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.

Chemical References

• Biomarkers, Tumor
• HLA-G Antigens
• Protein Isoforms

Topics

• Adenocarcinoma (diagnosis, metabolism)
• Biomarkers, Tumor (biosynthesis)
• Blotting, Western
• Carcinoma, Adenosquamous (diagnosis, metabolism)
• Carcinoma, Squamous Cell (diagnosis, metabolism)
• Diagnosis, Differential
• Female
• Flow Cytometry
• HLA-G Antigens (biosynthesis)
• Humans
• Immunohistochemistry (methods)
• Kaplan-Meier Estimate
• Lung Neoplasms (diagnosis, metabolism)
• Male
• Middle Aged
• Multivariate Analysis
• Prognosis
• Protein Isoforms (biosynthesis)
• ROC Curve