The significance of programmed cell death ligand 1 expression in resected lung adenocarcinoma.
BACKGROUND
Lung adenocarcinoma (AD) is a common variant of non-small cell lung cancer (NSCLC). Programmed cell death protein 1/programmed cell death ligand 1 (PD1/PD-L1) are promising immunotherapy targets and its expression may be an important biomarker of predicting clinical response. In this study, we evaluated PD-L1 expression in conjunction with clinicopathological characteristics and outcomes in resected lung adenocarcinoma.


RESULTS
This study included 133 cases of lung adenocarcinoma. PD-L1 expression rate in lung adenocarcinoma was 16.5% at the mRNA level and 13.5% at the protein level, and the kappa coefficient of the two examination methods was 0.824 (P = 0.219, highly correlated). PD-L1 was highly expressed in male patients and smokers with lung adenocarcinoma (P = 0.019 and 0.002, respectively), while no associations were identified between PD-L1 expression and age, tumor size, clinical stage, positive pleural invasion, lymph node metastasis, or therapy methods. Overexpression of PD-L1 was a significant indicator of shorter recurrence free survival time and overall survival (P = 0.000 and 0.000, respectively). Multivariate analysis revealed that PD-L1 expression was an independent risk factor for poor recurrence free survival and overall survival (P = 0.009 and 0.016, respectively).


METHODS
Expression of PD-L1 was examined with immunohistochemistry, using the VENTANA PD-L1 (SP263) rabbit monoclonal antibody. mRNA levels of PD-L1 were evaluated using in situ hybridization.


CONCLUSIONS
PD-L1 overexpression is more frequently observed in male patients and smokers in lung adenocarcinoma. PD-L1 expression is an indicator of worse prognosis in surgically resected lung adenocarcinoma patients.
Department of Pathology, Peking Union Medical College Hospital, Beijing, China.
Shafei
S
Wu
Department of Pathology, Peking Union Medical College Hospital, Beijing, China.
Xiaohua
X
Shi
Department of Pathology, Peking Union Medical College Hospital, Beijing, China.
Jian
J
Sun
Department of Pathology, Peking Union Medical College Hospital, Beijing, China.
Yuanyuan
Y
Liu
Department of Pathology, Peking Union Medical College Hospital, Beijing, China.
Yufeng
Y
Luo
Department of Pathology, Peking Union Medical College Hospital, Beijing, China.
Zhiyong
Z
Liang
Department of Medical Oncology, Beijing Tuberculosis and Thoracic Tumor Research Institute, Beijing Chest Hospital, Capital Medical University, Beijing, China.
Jinghui
J
Wang
Department of Pathology, Peking Union Medical College Hospital, Beijing, China.
Xuan
X
Zeng
D000230:Adenocarcinoma / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D000077192:Adenocarcinoma of Lung; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D060890:B7-H1 Antigen / Q000096:biosynthesis* / Q000235:genetics; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D008175:Lung Neoplasms / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D011379:Prognosis
D060890:B7-H1 Antigen; C423236:CD274 protein, human
immunohistochemistry; in situ hybridization; lung adenocarcinoma; programmed cell death ligand 1