Abstract 18P
Background
AURKA is a protein that regulates mitotic spindle formation and p53 is involved in cell cycle regulation. p53 mutations and AURKA overexpression is a frequent alteration in both TNBC and HGSOC cell lines which lead to carboplatin sensitivity. APR-246 is a new targeted agent that modulates abnormal p53 in mutated cells. The aim of our study was to assess the effect of the combination of carboplatin (carbo) plus APR-246 in TNBC and HGSOC cell lines.
Methods
We selected two TNBC (MDA-MB-231 and MDA-MB-436) and one HGSOC cell line (Kuramochi). Next-generation sequencing was performed in order to assess more relevant mutations. MTT experiments were performed to calculate the IC50 for APR-246 and carbo. For the combination (combo) increasing IC50 of either APR-246 or carbo was assessed in the presence of a constant concentration of each other. Western-blot (WB) and PCR analysis was performed in each line after exposure to APR-246, carbo or the combination to determine expression of AURKA and p53.
Results
The mutation profile of each line and the IC50 of APR-245, carbo and combo is shown in the table. Table: 18P
| P53 - BRCA | IC50 carbo | P value | IC50 carbo in Combo (APR-246 constant) | IC50 APR-246 | IC50 APR-246 in combo (carbo constant) | P value | |
| MDA-MB-231 | Mut - wt | 242.6 uM | <0.0001 | 41.77 uM | 22.37 uM | 12.19 uM | <0.0001 |
| MDA-MB-436 | Wt - mut | 38.73 uM | <0.0001 | 5.01 uM | 18.81 uM | 8.85 uM | <0.0001 |
| Kuramochi | Mut - mut | 35.86 uM | <0.0001 | 18.86 uM | 21.78 uM | 13.97 uM | <0.0001 |
Our results showed that IC50 of carbo and APR-246 decreased when administered in combination with constant doses of each other regardless of the subtype (TNBC vs HGSOC) and p53 mutations but more evident in the MDA-MB-231 BRCAwt cell line. PCR in MDA-MB-231 and MDA-MB-436 showed that AURKA was overexpressed by exposure to APR-246, Carbo and combo and p53 was upregulated after carbo (both lines) or combo (only 436). Kuramochi cells showed an underexpression of AURKA after combo and an upregulation of p53 after carbo or combo. Similar results were shown with WB in these cell lines.
Conclusions
Addition of APR246 to carboplatin increased apoptosis in both TNBC and HGSOC cell lines regardless of p53 mutations status in this in vitro study. AURKA and p53 expression was modified after exposure to carbo or combo.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
The authors.
Funding
Mutua Madrileña Grant Sociedad Española de Oncologia Medica Grant.
Disclosure
A. Lluch-Hernandez: Financial Interests, Personal, Advisory Board: Novartis; Financial Interests, Personal, Advisory Board: Pfizer; Financial Interests, Personal, Advisory Board: Roche; Financial Interests, Personal, Advisory Board: Eisai; Financial Interests, Personal, Advisory Board: Celgene; Financial Interests, Institutional, Research Grant: Roche; Financial Interests, Institutional, Research Grant: AstraZeneca; Financial Interests, Institutional, Research Grant: Merck; Financial Interests, Institutional, Research Grant: PharmaMar; Financial Interests, Institutional, Research Grant: Novartis; Financial Interests, Institutional, Research Grant: Boehringer Ingelheim; Financial Interests, Institutional, Research Grant: Pfizer; Financial Interests, Institutional, Research Grant: Eisai; Financial Interests, Institutional, Research Grant: Celgene; Financial Interests, Institutional, Research Grant: Pierre Fabre; Financial Interests, Personal, Other: Roche; Financial Interests, Personal, Other: Novartis. A. Cervantes: Financial Interests, Personal, Invited Speaker: MerckSerono; Financial Interests, Personal, Invited Speaker: Amgem; Financial Interests, Personal, Advisory Board: BeiGene; Financial Interests, Personal, Advisory Board: BMS; Financial Interests, Personal, Member: Annals of Oncology; Financial Interests, Personal, Member of the Board of Directors: Cancer Treat Reviews; Financial Interests, Institutional, Principal Investigator: Abbvie; Financial Interests, Institutional, Principal Investigator: Actuate Therap; Financial Interests, Institutional, Principal Investigator: Alkermes Inc; Financial Interests, Institutional, Principal Investigator: Amgem; Financial Interests, Institutional, Principal Investigator: BeiGene; Financial Interests, Institutional, Principal Investigator: Boehringer; Financial Interests, Institutional, Principal Investigator: Debiopharm; Financial Interests, Institutional, Principal Investigator: Roche; Financial Interests, Institutional, Principal Investigator: Fibrogen; Financial Interests, Institutional, Principal Investigator: Genmab; Financial Interests, Institutional, Principal Investigator: Janssen; Financial Interests, Institutional, Principal Investigator: MedImmune; Financial Interests, Institutional, Principal Investigator: Novartis; Financial Interests, Institutional, Principal Investigator: Puma Biotech; Financial Interests, Institutional, Principal Investigator: Symphogen; Financial Interests, Institutional, Principal Investigator: Tahio; Financial Interests, Institutional, Principal Investigator: Transgene; Financial Interests, Institutional, Principal Investigator: WNT Research; Non-Financial Interests, Institutional, Member of the Board of Directors: INCLIVA Biomedical Institute of Research. J.A. Perez Fidalgo: Financial Interests, Personal, Invited Speaker: GSK; Financial Interests, Personal, Invited Speaker: Clovis; Financial Interests, Personal, Invited Speaker: AstraZeneca; Financial Interests, Personal, Invited Speaker: PharmaMar; Financial Interests, Institutional, Funding: GSK; Financial Interests, Institutional, Research Grant: PharmaMar; Financial Interests, Personal, Advisory Board: Abilify pharma; Financial Interests, Personal, Advisory Board: GSK; Financial Interests, Personal, Advisory Board: Clovis; Financial Interests, Personal, Advisory Role: AstraZeneca; Financial Interests, Personal, Advisory Board: Roche; Financial Interests, Personal, Invited Speaker: Roche; Financial Interests, Institutional, Project Lead: Novartis; Financial Interests, Institutional, Principal Investigator: AstraZeneca; Financial Interests, Institutional, Principal Investigator: GSK; Financial Interests, Institutional, Principal Investigator: Immunogene; Financial Interests, Institutional, Project Lead: AstraZeneca; Financial Interests, Institutional, Principal Investigator: Karyopharm. All other authors have declared no conflicts of interest.