Abstract 5781
Background
Exosomes are small membranous vesicles (around 40-130 nm), that have been detected in different biological samples, that play a key role in NSCLC and being relevant in stem cell differentiation as well. The main objective of this study was to analyze the exosomes cargo from NSCLC cell cultures growth in monolayer (2D) and suspension conditions (3D, lung tumorespheres).
Methods
Cultures were established from NSCLC resected patients and cell lines. Exosomes isolation was performed by ultracentrifugation. Characterization was carried out by NTA, electron microscopy, immunoblot and flow cytometry. Mutational status of EGFR and RAS genes was analyzed by BEAMing dPCR. Transcriptomic analysis has been carried out from exosomal RNA with microarrays, (p ≤ 0.01). Consequently, XAGE1B (significantly expressed gene in exosomes) was analyzed by RTqPCR in 189 paired fresh-frozen tumor and normal tissue samples of resected NSCLC. Prognostic value was assessed by Kaplan‐Meier curves (log rank‐test), considering significant p < 0.05.
Results
Exosomal characterization through NTA and electron microscopy showed an exosomes size from 108-125 nm. Specific markers were detected by IB and FC. Mutational analysis of EGFR and RAS genes in exosomes shown the same pattern displayed by the origin cells. Transcriptomic analysis showed that the expression of mRNAs, miRNAs and precursors were significantly different between 3D and 2D-derived exosomes. A pathway enrichment was carried out to know in which processes (cancer-related) are involved. Significant differential expression was also found between ADC vs SCC–derived exosomes. Concretely, XAGE1B is overexpressed in ADC-derived exosomes (p = 0.00003). This overexpression in ADC was validated in NSCLC cohort (p = 0.002). Furthermore, it has revealed a significant association with patient prognosis for overall survival in the ADC group (n = 74)(OS 49.8 vs. NR months, p = 0.043).
Conclusions
Differences in exosomal cargo have been observed between: i) 3D vs. 2D cultures and ii) ADC vs. SCC. In addition, the same mutational pattern was detected in exosomes as compared with parental cells. Therefore, exosomes can be a useful source of biomarkers in NSCLC analysis. Supported by grant GV/2018/026, PI18/00266, & AECC Valencia.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
Fundación de Investigación del Hospital General Universitario de Valencia.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.
Resources from the same session
1885 - Factors associated with disease progression in patients treated with trametinib in combination with dabrafenib for unresectable advanced BRAFV600-mutant melanoma: an open label, non randomized study
Presenter: Philippe Saiag
Session: Poster Display session 3
Resources:
Abstract
5259 - Integrative RNAseq and Target panel sequencing reveals common and distinct innate and adaptive resistance mechanisms to BRAF inhibitors
Presenter: Phil Cheng
Session: Poster Display session 3
Resources:
Abstract
5619 - Effective treatment with T-VEC monotherapy in Stage IIIB/C-IVM1a Melanoma of the Head & Neck Region
Presenter: Viola Franke
Session: Poster Display session 3
Resources:
Abstract
5666 - Re-introduction of T-VEC Monotherapy in Recurrent Stage IIIB/C-IVM1a melanoma is effective
Presenter: Viola Franke
Session: Poster Display session 3
Resources:
Abstract
4117 - Efficacy of talimogene laherparepvec (T-VEC) in melanoma patients (pts) with locoregional (LR) recurrence, including in-transit metastases (ITM): subgroup analysis of the phase 3 OPTiM study
Presenter: Mark Middleton
Session: Poster Display session 3
Resources:
Abstract
5303 - Real Life Use of Talimogene Laherparepvec in Melanoma in Centers in Austria and Switzeland
Presenter: Christoph Hoeller
Session: Poster Display session 3
Resources:
Abstract
4130 - Outcomes of advanced melanoma patients who discontinued pembrolizumab (pembro) after complete response (CR) in the French early access program (EAP)
Presenter: Philippe Saiag
Session: Poster Display session 3
Resources:
Abstract
2050 - Outcome of patients with elevated LDH treated with first-line targeted therapy (TT) or PD-1 based immune checkpoint inhibitors (ICI)
Presenter: Sarah Knispel
Session: Poster Display session 3
Resources:
Abstract
1618 - Comparative-Effectiveness of Pembrolizumab vs. Nivolumab for Patients with Metastatic Melanoma
Presenter: Justin Moser
Session: Poster Display session 3
Resources:
Abstract
3556 - Long-term efficacy of combination nivolumab and ipilimumab for first-line treatment of advanced melanoma: a network meta-analysis
Presenter: Peter Mohr
Session: Poster Display session 3
Resources:
Abstract