Abstract 3264
Background
A subgroup of MEK1 mutations in human tumors were recently described as RAF- and phosphorylation independent and as insensitive to currently clinically used allosteric MEK inhibitors. We established a novel cell line that carries a MEK1 mutation of this class (pGlu102_Lys104delinsGln) and tested a novel ATP competitive MEK inhibitor (MAP855) in this model. According to our knowledge this is the first patient derived cell line with this type of MEK mutation and the first spitzoid melanoma cell model.
Methods
PF130 cell line was established from the pleural effusion sample of a 37-year-old male patient with spitzoid melanoma. NGS was used for mutational analysis. Cells were treated either with allosteric MEK inhibitor selumetinib or with newly developed ATP competitive MEK inhibitor MAP855. We analyzed changes in cell number, cell cycle distribution and ERK activation after treatment in vitro. Furthermore, the in vivo tumorigenicity was tested by injecting the cells subcutaneously, intrapleurally or intravenously into female SCID mice.
Results
We found that ATP competitive MEK inhibitor MAP855 strongly decreased the viability of PF130 cells, while allosteric inhibitor selumetinib did not. Cell cycle analysis showed that MAP588 treatment could induce cell death in PF130 cells in a concentration dependent manner and slightly reduced the amount of cells in the S and the G2M phases. Furthermore, MAP855 was able to reduce ERK protein activation in PF130 cells effectively while selumetinib treatment had no effect. In vivo, intrapleurally injected cells established macroscopic tumors in the chest cavity after two months while intravenously and subcutaneously delivered cells showed limited growth.
Conclusions
We established a new cellular model of tumors with RAF- and phosphorylation independent MEK mutation. We found that recently developed ATP-competitive MEK inhibitor MAP855 is a potent inhibitor of these cells in vitro. The in vivo efficacy is currently under investigation. Furthermore, we describe here to the best of our knowledge the first patient derived spitzoid melanoma cell model to test both in vitro and in vivo novel therapeutic modalities.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
Balazs Hegedus.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.
Resources from the same session
3186 - The landscape of immuno-oncology clinical trials in China
Presenter: Dawei Wu
Session: Poster Display session 3
Resources:
Abstract
3468 - Clinical Significance of Immune-related Creatine Phosphokinase Increase Associated with Anti PD1/PD-L1 immunotherapies.
Presenter: Samia Hajem
Session: Poster Display session 3
Resources:
Abstract
3836 - Thyroid toxicity and anti-thyroid antibodies as predictive markers for patients treated with anti-PD1 checkpoint therapy
Presenter: Wim Meer
Session: Poster Display session 3
Resources:
Abstract
1343 - Treatment-related adverse events and tolerability in patients with advanced renal cell carcinoma treated with first-line combination therapy with checkpoint inhibitors
Presenter: Thura Win Htut
Session: Poster Display session 3
Resources:
Abstract
5783 - Immune-related adverse events (irAEs) with single-agent PD-1 vs PD-L1 inhibitors: a meta-analysis of 8,730 patients from clinical trials
Presenter: Guru Sonpavde
Session: Poster Display session 3
Resources:
Abstract
5422 - EULAR recommendations for the diagnosis and the management of rheumatic immune-related adverse events due to cancer immunotherapy
Presenter: Marie Kostine
Session: Poster Display session 3
Resources:
Abstract
1202 - Radiographic characteristics and poor prognostic factors of interstitial lung disease (ILD) in nivolumab-treated patients with non-small cell lung cancer (NSCLC)
Presenter: Shinichi Sasaki
Session: Poster Display session 3
Resources:
Abstract
2749 - Use of Checkpoint Inhibitors (CPI) in Allogeneic Stem Cell Transplant Recipients: An Institutional Experience and A Systemic Review of the Literature
Presenter: Chantal Saberian
Session: Poster Display session 3
Resources:
Abstract
3256 - Deep Learning Radiomics distinguishes intrapulmonary Disease from Metastases in Immunotherapy-treated Melanoma Patients
Presenter: Thi Dan Linh Nguyen-Kim
Session: Poster Display session 3
Resources:
Abstract
5031 - Sarcoidosis-Like Reaction Mimics Progression in patients treated with immune checkpoint inhibitors
Presenter: Sophie Hans
Session: Poster Display session 3
Resources:
Abstract