Abstract 3633
Background
Aurora Kinases (AURK) regulate mitosis and are often upregulated in cancer. SCLC is characterized by TP53 and RB1 loss and frequent MYC amplification. Our group, and others, have proved that MYC-driven SCLC are vulnerable to AURKA-inhibitors (AURKAi), but their use is limited by toxicity due to high AURKA expression. AURKB levels are variable in SCLC, making AURKB an attractive targeted therapeutic approach. A novel AURKBi, AZD2811NP (nanoparticle), is now being investigated in relapsed SCLC patients (NCT02579226). We hypothesize that molecularly defined subsets may be sensitive to AZD2811.
Methods
We tested 50 human-derived SCLC cell lines with AZD2811 in 96 hour proliferation assays. To identify translatable biomarkers of response, we correlated IC50 values with genomic (WES), transcriptomic (RNASeq), and proteomic profiling (RPPA).
Results
AZD2811 is active in a subset of SCLC cells: 13/30 (26%) have high sensitivity (IC50<30 nM, Cmax) and 7/30 (14%) intermediate (IC50=30-100nM). Comparing protein expression, we found that cMYC (Fold change, FC:2.5; P = 0.015) and Vimentin (FC:1.66; P = 0.022) were top biomarkers of sensitivity, while high E-cadherin (FC:1.94; P = 0.046) and BCL-2 (FC:1.86; P = 0.032) associated with resistance. Interestingly, among the 13 highly sensitive cells, only 5 overexpress cMYC, highlighting that activity of AURKBi is not limited to MYC-driven SCLC. Indeed, among recently-described transcription factor defined subsets of SCLC, a majority of the NEUROD1-defined subset (cMYC enriched) were sensitive to AZD2811, as 25% of ASCL1- and 67% of POU2F-3-defined ones. These data suggest that the ASCL1 subset includes heterogeneous sub-groups that require further analysis to dissect their molecular features. Mutations in EP300, a Histone acetyltransferase that controls chromatin modification and transcription, also predict sensitivity.
Conclusions
Our results show encouraging single agent in vitro activity of AZD2811 in SCLC cells, and suggest a novel biomarker-driven approach for combinations. Candidate biomarkers will be tested in samples from the ongoing clinical trial. The high BCL2 levels observed in resistant cells provide a rationale for exploring AURKB/BCL2-i combinations.
Clinical trial identification
NCT02579226.
Editorial acknowledgement
Legal entity responsible for the study
The authors.
Funding
AstraZeneca.
Disclosure
C.A. Adelman: Full / Part-time employment: AstraZeneca. J. Travers: Full / Part-time employment: AstraZeneca. J. Heymach: Advisory / Consultancy, Research grant / Funding (self): AstraZeneca; Advisory / Consultancy, Licensing / Royalties: BioTree; Advisory / Consultancy: Boehringer Ingelheim; Advisory / Consultancy: Exelixis; Advisory / Consultancy: Genentech; Advisory / Consultancy: GSK; Advisory / Consultancy: Guardant Health; Advisory / Consultancy: Hengrui; Advisory / Consultancy: Lilly; Advisory / Consultancy: Novartis; Advisory / Consultancy, Research grant / Funding (self), Licensing / Royalties: Spectrum; Advisory / Consultancy: EMD Serono; Advisory / Consultancy: Synta; Research grant / Funding (self): Bayer; Research grant / Funding (self): GlaxoSmithKline. L.A. Byers: Advisory / Consultancy, Research grant / Funding (self): AstraZeneca; Advisory / Consultancy, Research grant / Funding (self): AbbVie; Advisory / Consultancy, Research grant / Funding (self): GenMab; Advisory / Consultancy: BergenBio; Advisory / Consultancy: Pharma Mar; Advisory / Consultancy: SA; Advisory / Consultancy, Research grant / Funding (self): Sierra Oncology; Research grant / Funding (self): Tolero Pharmaceuticals. All other authors have declared no conflicts of interest.
Resources from the same session
2935 - Correlation of progression free survival-2 and overall survival in solid tumors
Presenter: Paul Mainwaring
Session: Poster Display session 1
Resources:
Abstract
2273 - High performance of serial tumor biopsies in first in human (FIH) phase I trials.
Presenter: Jun Sato
Session: Poster Display session 1
Resources:
Abstract
5933 - Response rates and lesion-level progression patterns of solid tumor patients in an academic phase 1 program: implications for tumor heterogeneity
Presenter: Christopher Chen
Session: Poster Display session 1
Resources:
Abstract
3569 - Clinical Benefit and Response Rate in Early Phase Clinical Trials: First Report from a Single-Institution Study
Presenter: Antonio Marra
Session: Poster Display session 1
Resources:
Abstract
4139 - Patient (pt) selection for immunotherapeutic early-phase clinical trials (ieCTs): a single Phase I Unit experience
Presenter: Matteo Simonelli
Session: Poster Display session 1
Resources:
Abstract
4451 - Improving patient selection for immuno-oncology phase 1 trials: an external validation of five prognostic scores at Claudius Regaud Institute of Toulouse, Oncopôle (IUCT-O).
Presenter: Ghassan Al Darazi
Session: Poster Display session 1
Resources:
Abstract
1696 - Demonstrating the Changing Trends in Phase 1 Clinical Trials
Presenter: Christina Guo
Session: Poster Display session 1
Resources:
Abstract
3202 - Participation of Women in phase 1 oncology clinical trials
Presenter: Laura Vidal
Session: Poster Display session 1
Resources:
Abstract
4518 - Predictors for early trial discontinuation of patients with cancer participating in phase I clinical trials
Presenter: Joeri Douma
Session: Poster Display session 1
Resources:
Abstract
4368 - Safety of Tumor Treating Fields delivery to the torso: Meta analysis from TTFields clinical trials
Presenter: Federica Grosso
Session: Poster Display session 1
Resources:
Abstract