Abstract 3324
Background
To facilitate cancer precision medicine, breast cancer organoids have recently emerged as a useful pre-clinical model for retaining sufficient fidelity regarding histology, the transcriptome and genome. However, their potential to predict clinical treatment responses remains unclear.
Methods
We generated breast cancer organoids from breast cancer tissues and performed drug sensitivity test on these organoids based on genomic analysis data.
Results
A total of 25 fresh breast cancer tissues and biopsies from 22 patients were processed between November 2017 and February 2019. Breast cancer organoids were grown successfully from 10 out of 25 patients (40%). We performed histopathological analysis of H&E stained tissues and organoid sections and confirmed that the phenotypes of organoids matched the original histological breast cancer types. We also performed whole genome DNA sequencing (WGS) and RNA sequencing (RNA-seq) on breast cancer organoids and paired breast cancer tissues. One of these breast cancer organoids had HER2 mutations (previously shown to be an activating mutation) and retained expression of estrogen receptor (ER) and progesterone receptor (PR) (Luminal A subtype). In our previous work, we identified activating HER2 mutations (S310F D769Y V777L 778insGSP) in ER positive/HER2-amplification negative breast cancer, who had developed resistance to multi-line endocrine therapy. Two patients achieved a durable partial response (approximately 1 years) to trastuzumab combined with everolimus. We also showed that HER2 mutations were constitutively active, and T47D and MCF7 overexpressing HER2 mutations were sensitive to HER2 targeted therapies combined with everolimus. Hence, we tested the effects of trastuzumab and everolimus on this HER2-mutant breast cancer organoid in vitro and in vivo. HER2-targeted therapies combined with everolimus produced regression of the HER2-mutated organoid.
Conclusions
The breast cancer organoids may serve as a high-fidelity platform and recapitulate clinical treatment responses in personalized medicine. These data provide a strong preclinical rationale for combining HER2-targeted therapies with everolimus in HER2-mutant/ HER2-amplification negative breast cancer.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
The authors.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.
Resources from the same session
4596 - A Phase 2, Open-Label, Randomized, Multicenter Trial of Encorafenib + Binimetinib Evaluating a Standard-dose and a High-dose Regimen in Patients With BRAFV600-Mutant Melanoma Brain Metastasis (MBM) (POLARIS)
Presenter: Michael Davies
Session: Poster Display session 3
Resources:
Abstract
1891 - Continuation of annual screening mammograms and breast-cancer mortality in women over 70
Presenter: Xabier Garcia De Albeniz
Session: Poster Display session 3
Resources:
Abstract
5587 - Introducing standardized medical procedure and dynamic decision support program in precision oncology for the community of practice
Presenter: Istvan Petak
Session: Poster Display session 3
Resources:
Abstract
4757 - Effectively using primary care givers in oncology care through capacity building, task sharing and techno-mentoring.
Presenter: Dinesh Pendharkar
Session: Poster Display session 3
Resources:
Abstract
4497 - A single institution review of capecitabine related acute admissions and cost analysis
Presenter: Gemma Dart
Session: Poster Display session 3
Resources:
Abstract
2187 - Health status of middle-aged and older cancer survivors in China: results from the China Health and Retirement Longitudinal Study (CHARLS)
Presenter: Jiarui Li
Session: Poster Display session 3
Resources:
Abstract
5101 - Crossed looks on lung cancer perception and knowledge from general public and physicians in France: results of a two-fold survey
Presenter: Céline Mascaux
Session: Poster Display session 3
Resources:
Abstract
4354 - Knowledge and perception of clinical trials (CTs) and attitude towards participation among Polish oncological patients - A pilot survey
Presenter: Artur Kotowski
Session: Poster Display session 3
Resources:
Abstract
3499 - Achieving best possible cancer treatment outcomes in care pathways through benchmarking; ABC-Benchmarking
Presenter: Anke Wind
Session: Poster Display session 3
Resources:
Abstract
2270 - Impact of 10-day Fulbright Specialist Program (FSP) and Project Pink Blue (PPB) Education Sessions on Medical Oncology knowledge among Doctors that treat cancer in Nigeria
Presenter: Mike Martin
Session: Poster Display session 3
Resources:
Abstract