Abstract 4776
Background
Breast cancer is the second most diagnosed cancer globally accounting for over 2 million new worldwide cases of the disease in 2017. Chemotherapy (including cyclophosphamide and anthracyclines) is the mainstay for triple-negative breast cancer (TNBC) treatment. Despite high rates of responses to neoadjuvant chemotherapy, TNBC patients experience high rates of distant recurrence and less than 30% of patients with metastatic disease treated with chemotherapy will survive 5 years. These poor cancer patient outcomes highlight the need for novel companion diagnostics and therapies to identify the patients who will derive benefit and improve the response to therapy. Herein, we have identified ‘cell division cycle associated protein 3’ (CDCA3) as a novel protein that may prove useful to enhance chemotherapy response in TNBC.
Methods
Bioinformatics, Western blot, immunohistochemistry, siRNA depletion of CDCA3, CRISPR-Cas9 knockout, dose response, cell viability.
Results
CDCA3 transcripts are elevated across increasing grades of breast cancer, TNBC versus non-TNBC and in basal-like (BLIA and BLIS) versus luminal-AR and mesenchymal TNBC subtypes (METABRIC datasets). Elevated CDCA3 levels were strongly prognostic for patient outcome in high grade breast cancer and TNBC. Tissue microarray (TMA) immunohistochemistry analysis of over 300 breast cancers indicated heterogeneous CDCA3 staining is strongly prognostic in Ki67+ and TNBC cases of disease. CDCA3 staining correlated with markers of poor prognosis (nuclear grade, mitotic score, nuclear pleomorphism) and was associated with a poor prognosis. In vitro, we identified that, consistent with clinical data, CDCA3 levels were elevated in TNBC versus non-TNBC cell lines. In 10 TNBC cell lines, endogenous CDCA3 expression correlated with sensitivity to both cisplatin and doxorubicin, with CDCA3high levels having higher IC50 values and thereby being associated with a poor prognosis. Consistently, depleting these cells of CDCA3 markedly enhanced sensitivity to both cisplatin and doxorubicin.
Conclusions
Our data highlight CDCA3 as a novel prognostic factor in TNBC that modulates sensitivity to chemotherapy. These findings point to the therapeutic potential of targeting CDCA3 in TNBC.
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
3006 - Nal-iri/lv5-fu versus paclitaxel as second-line therapy in patients with metastatic esophageal squamous cell carcinoma (OESIRI-PRODIGE 62): A FFCD multicenter, randomized, phase II study.
Presenter: Violaine Randrian
Session: Poster Display session 2
Resources:
Abstract
3697 - The expression of Versican and its role in pancreatic neuroendocrine tumor
Presenter: Zhao Sun
Session: Poster Display session 2
Resources:
Abstract
6073 - Characteristics of patients with thyroid carcinoma in the united states
Presenter: Dina El-Habashy
Session: Poster Display session 2
Resources:
Abstract
2124 - The discrimination of pituitary adenomas and craniopharyngioma on MRI: from image features to texture features
Presenter: Hanyue Xu
Session: Poster Display session 2
Resources:
Abstract
3786 - Proportion of Peripheral Lymphocyte Subsets Correlates with the Progression-free Survival and Metastatic Status of Pancreatic Neuroendocrine Tumor Patients
Presenter: Yitao Gong
Session: Poster Display session 2
Resources:
Abstract
2263 - Immunohistochemical expression of ER-α and PR in papillary thyroid carcinoma
Presenter: Enas Elkhouly
Session: Poster Display session 2
Resources:
Abstract
4386 - SILVELUL Project: Immunohistochemical panel analyses as potential predictive and prognostic factors in Pancreatic Neuroendocrine Tumors (PanNET) Treated with CAPTEM or Everolimus
Presenter: Ana De Jesus-Acosta
Session: Poster Display session 2
Resources:
Abstract
2302 - Carcinoid heart disease (CHD): the CRUSOE-NETs, a prospective cohort study from the French Group of Endocrine Tumors (GTE)
Presenter: Kathleen Dekeister Geoffroy
Session: Poster Display session 2
Resources:
Abstract
5749 - Safety of high doses of somatostatin analogs in well differentiated NENs in elderly
Presenter: Massimiliano Cani
Session: Poster Display session 2
Resources:
Abstract
3931 - Differences in multikinase inhibitors (MKI) toxicity profile according to gender. A pooled analysis of three phase II trials with lenvatinib, pazopanib and sorafenib in patients (pts) with advanced gastroenteropancreatic (GEP) neuroendocrine tumors (NETs).
Presenter: Jorge Hernando Cubero
Session: Poster Display session 2
Resources:
Abstract