Abstract 1922
Background
The aim of this study was to research whether there was expression of PD-L1 in plasma exosome of NSCLC patients and whether its expression can partly represent PD-L1 expression of corresponding lung tumor tissues.
Methods
Plasma was collected before and after surgery of NSCLC patients with stage II to stage III. Plasma of NSCLC patients with stage IV was also collected before and after anti-PD-1/PD-L1 therapy. Digital PCR was used to detect PD-L1 and β-actin mRNA expression of plasma exosomes. Expression of PD-L1 in tumor tissues was determined by immunohistochemical staining (22C3). Pearson correlation analysis and wilcoxon rank sum test was performed by SPSS 22.0.
Results
A total of 126 patients (54 patients with surgery and 72 patients with non-surgery therapy) were participated in this study. Exosomal PD-L1 expression can be detected in all plasma samples. Exosomal expression of PD-L1 calculated by both absolute quantification method and relative quantification method showed a positive correlation with PD-L1 expression of tumor tissues (absolute quantification method: r2=0.289, P = 0.001; relative quantification method: r2=0.547, P = 0.000). However, expression of exosomal PD-L1 calculated by relative quantification calculation showed higher correlation. Exosomal PD-L1 expression significantly decreased after surgery (P < 0.001) and three patients who showed good response (PR) to anti-PD-1/PD-L1 therapy also showed significantly decreasing exosomal PD-L1 expression after anti-PD-1/PD-L1 therapy (P < 0.001).
Conclusions
Plasma exosomes of NSCLC patients contains substantial expression of PD-L1. Plasma exosomal PD-L1 expression showed high correlation with PD-L1 expression of tumor tissues. Exosomal PD-L1 expression could represent PD-L1 expression of tumor tissues and might be a potential predictive marker for anti-PD-1/PD-L1 therapy.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
Jifeng Feng.
Funding
The National Natural Science Foundation of China.
Disclosure
All authors have declared no conflicts of interest.
Resources from the same session
2477 - Antecedent of cancer and mortality after the first ST segment elevation acute myocardial infarction treated with primary coronary angioplasty. A prospective cohort study
Presenter: Irene Sillero
Session: Poster Display session 3
Resources:
Abstract
1894 - Genomic characterisation of locally advanced pancreatic adenocarcinoma
Presenter: Sarah Picardo
Session: Poster Display session 3
Resources:
Abstract
3280 - Comparison of freshly prepared and frozen cells from colorectal cancer surgical samples for phenotyping experiments- a pilot study
Presenter: Sandra Mersakova
Session: Poster Display session 3
Resources:
Abstract
3419 - Hyaluronan (HA) Accumulation in the Tumor Microenvironment (TME) is Increased in Colorectal Cancer (CRC) and Associated with Consensus Molecular Subtypes (CMS) 4 Molecular Subtype
Presenter: Barbara Blouw
Session: Poster Display session 3
Resources:
Abstract
1833 - Evaluation of CT-based radiomics in patients with renal cell carcinoma
Presenter: An Zhao
Session: Poster Display session 3
Resources:
Abstract
5883 - Detection of Double Protein Expression in Diffuse Large B Cell Lymphoma
Presenter: Mohamed Gouda
Session: Poster Display session 3
Resources:
Abstract
5415 - Encyclopedic Tumor Analysis for organ agnostic treatment with Axitinib in combination regimens for advanced cancers
Presenter: Tim Crook
Session: Poster Display session 3
Resources:
Abstract
3297 - Computational model to predict response rate of clinical trials
Presenter: Orsolya Lorincz
Session: Poster Display session 3
Resources:
Abstract
4355 - Analysis of BRCA genes and homologous recombination deficiency (HRD) scores in tumours from patients (pts) with metastatic breast cancer (mBC) in the OlympiAD trial
Presenter: Mark Robson
Session: Poster Display session 3
Resources:
Abstract
2316 - A 3D co-culture platform of breast cancer and patient derived immune cells to analyse the response to chemotherapy and immunotherapies
Presenter: Diana Saraiva
Session: Poster Display session 3
Resources:
Abstract