Abstract 5198
Background
Taxanes are the most active chemotherapeutic agents in metastatic castration-resistant prostate cancer (mCRPC), with demonstrated survival benefit. However, patients eventually develop resistance and no predictive molecular biomarkers are clinically available. This study analysed molecular changes associated with cell plasticity in CRPC-cell models resistant to docetaxel (D) and cabazitaxel (CZ), as well as in circulating tumour cells (CTCs) and tumour biopsies from patients with mCRPC treated with taxanes.
Methods
cDNA microarrays were performed in D and CZ-resistant (DR and CZR) DU-145 and PC-3 cell lines. Differential gene expression of a gene subset was validated by qRT-PCR and Western Blot analyses. Gene expression was evaluated in CTCs enriched samples and tumour samples from 22 and 118 patients, respectively.
Results
Microarrays analysis revealed a pronounced and intermediate epithelial-mesenchymal transition phenotype in DR and CZR cells, respectively. The penetrance of stem-cell-like and neuroendocrine phenotypes generated by D and CZ-resistance differed in the DR and CZR models. Gene expression changes also occurred in CTCs after taxane treatment. Low expression of ESRP1 in tumour samples predicted lower PSA-progression-free survival (PFS) in D-treated (HR 0.4, 95%CI 0.2-0.7, P < 0.001) than in CZ-treated patients (HR 2.3, 95%CI 1.1-4.8, P = 0.034). Moreover, tumour EMT phenotype (defined by ESRP1 downregulation and ZEB1 and AXL overexpression) was also associated with a lower PSA-PFS to D (HR 2.2, 95%CI 1.3-3.8, P = 0.005), contrary to CZ (HR 0.3, 0.1-0.7, P = 0.006). NE-markers EZH2 and SYP correlated with lower OS in D (HR 1.6, 95%CI 1.1-2.5, P = 0.023) and CZ (HR 3.6, 95%CI 1.6-8.1, P = 0.002), respectively.
Conclusions
Molecular changes associated with cell plasticity are different in D or CZ resistance. The EMT profile expression in primary tumour was differentially associated to D or CZ benefit. ESRP1 expression in tumour may be a potential predictive biomarker of different sensitivity to D and CZ.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
Hospital Clínic de Barcelona.
Funding
Instituto de Salud Carlos III-Subdirección General de Evaluación y Fomento de la Investigación; European Regional Development Fund (ERDF); CERCA Programme/Generalitat de Catalunya; Astellas Pharma S.A; Sanofi.
Disclosure
N. Jimenez: Travel / Accommodation / Expenses: Sanofi. O. Reig: Speaker Bureau / Expert testimony, Travel / Accommodation / Expenses: Ipsen; Speaker Bureau / Expert testimony: Pfizer; Speaker Bureau / Expert testimony: Sanofi; Speaker Bureau / Expert testimony: Bristol-Myers Squibb; Speaker Bureau / Expert testimony: Janssen-Cilag; Speaker Bureau / Expert testimony: Bayer. A. Font: Advisory / Consultancy, Travel / Accommodation / Expenses: Roche; Advisory / Consultancy: Sanofi; Advisory / Consultancy: Janssen; Research grant / Funding (institution), Travel / Accommodation / Expenses: Astra-Zeneca; Research grant / Funding (institution), Travel / Accommodation / Expenses: Astellas; Research grant / Funding (institution): Pierre Fabre. A. Rodriguez-Vida: Advisory / Consultancy, Speaker Bureau / Expert testimony, Research grant / Funding (institution): MSD; Advisory / Consultancy, Speaker Bureau / Expert testimony, Research grant / Funding (institution): Pfizer ; Research grant / Funding (institution): Takeda; Advisory / Consultancy, Speaker Bureau / Expert testimony: Astellas; Speaker Bureau / Expert testimony: Astra-Zeneca; Advisory / Consultancy, Speaker Bureau / Expert testimony: Bayer; Advisory / Consultancy, Speaker Bureau / Expert testimony: Bristol-Myers Squibb; Advisory / Consultancy, Speaker Bureau / Expert testimony: Janssen; Advisory / Consultancy, Speaker Bureau / Expert testimony: Roche; Advisory / Consultancy, Speaker Bureau / Expert testimony: Ipsen; Speaker Bureau / Expert testimony: Sanofi-Aventis; Advisory / Consultancy: Clovis. J. Carles: Advisory / Consultancy, Speaker Bureau / Expert testimony: Bayer; Advisory / Consultancy, Speaker Bureau / Expert testimony: Johnson&Johnson; Advisory / Consultancy: Bristol-Myers Squibb; Advisory / Consultancy, Speaker Bureau / Expert testimony: Astellas; Advisory / Consultancy: Pfizer; Advisory / Consultancy: Sanofi; Advisory / Consultancy: MSD ; Advisory / Consultancy: Roche; Advisory / Consultancy: Astra-Zeneca; Speaker Bureau / Expert testimony: Asofarma. C. Suárez: Advisory / Consultancy, Speaker Bureau / Expert testimony, Travel / Accommodation / Expenses: Bristol-Myers Squibb; Advisory / Consultancy, Speaker Bureau / Expert testimony: Ipsen; Advisory / Consultancy: Sanofi; Advisory / Consultancy, Speaker Bureau / Expert testimony: Pfizer; Advisory / Consultancy: EUSA Pharma; Advisory / Consultancy: Astellas ; Advisory / Consultancy: Novartis; Speaker Bureau / Expert testimony: Roche/Genentech; Speaker Bureau / Expert testimony: Astra-Zeneca; Travel / Accommodation / Expenses: Roche. M. Domenech: Advisory / Consultancy, Speaker Bureau / Expert testimony, Travel / Accommodation / Expenses: Roche; Advisory / Consultancy, Speaker Bureau / Expert testimony: Bristol-Myers; Advisory / Consultancy, Speaker Bureau / Expert testimony: MSD; Advisory / Consultancy, Speaker Bureau / Expert testimony: Sanofi; Advisory / Consultancy, Speaker Bureau / Expert testimony: Pfizer; Travel / Accommodation / Expenses: Astellas; Travel / Accommodation / Expenses: Janssen. N. Sala-González: Advisory / Consultancy, Travel / Accommodation / Expenses: Pfizer; Advisory / Consultancy, Travel / Accommodation / Expenses: Astellas; Advisory / Consultancy, Travel / Accommodation / Expenses: Bristol-Myers Squibb; Advisory / Consultancy, Travel / Accommodation / Expenses: Ipsen. A. Prat: Advisory / Consultancy, Speaker Bureau / Expert testimony: Roche; Advisory / Consultancy, Speaker Bureau / Expert testimony: Pfizer; Advisory / Consultancy, Speaker Bureau / Expert testimony: Novartis; Advisory / Consultancy, Speaker Bureau / Expert testimony: Daiichi Sankyo; Advisory / Consultancy, Speaker Bureau / Expert testimony: Nanostring; Advisory / Consultancy, Speaker Bureau / Expert testimony: MSD; Advisory / Consultancy, Speaker Bureau / Expert testimony: Lilly. M. Marín-Aguilera: Travel / Accommodation / Expenses: Bristol-Myers Squibb. B. Mellado: Advisory / Consultancy, Research grant / Funding (institution): Roche; Advisory / Consultancy: Sanofi; Advisory / Consultancy, Travel / Accommodation / Expenses: Janssen; Advisory / Consultancy: Astellas; Advisory / Consultancy, Travel / Accommodation / Expenses: Pfizer; Advisory / Consultancy: Novartis; Advisory / Consultancy: Bristol-Myers Squibb; Advisory / Consultancy: Ipsen; Research grant / Funding (institution): Bayer. All other 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