Oncology Abstracts

This study evaluates the efficacy of two newly developed selective CDK9 inhibitors (CDK9i) across a panel of TNBC cell lines. MDA-MB-453, MFM-223, MDA-MB-468 and MDA-MB-231 TNBC cells were treated with increasing concentrations of two novel and highly selective CDK9 inhibitors and the effect on proliferation, apoptosis and expression of CDK9 targets determined. MDA-MB-453 and -468 cells showed significant growth inhibition with as little as 150 nM of CDK9i, evident 3 days afte...

Steroid hormone receptors (SHR) play a major role in the normal breast development and breast cancer progression. Estrogen receptor (ER) is expressed in approximately 75% of breast cancers, and the majority of these tumours also express the androgen receptor (AR). While ER-directed therapies have been effective in the majority of patients, a significant subset develops resistance and requires alternative treatment approaches. In the endocrine-resistant setting, emerging insigh...

Introduction: 75% of breast cancers (BCa) are driven by the estrogen receptor α (ER+). Tumours lacking ER (ER-) are more aggressive and have the poorest prognosis. The androgen receptor (AR) is also widely expressed in BCa (90% of primary tumours). FOXA1 is a pioneer factor required for oncogenic AR signalling in PCa but its role in AR signaling in ER-BCa is not clear. We previously showed that cell growth is increased when FOXA1 is overexpressed in AR-driven PCa and BCa ...

Mammographic density (MD) is an independent risk factor for breast cancer, however what molecule or pathway within MD tissue contributes to this risk? High MD is characterized by an abundance of connective tissue stroma which is rich in heparan sulfate proteoglycans (HSPGs). Of these, SDC1 and SDC4 are upregulated in breast cancer, and we have observed a significantly higher abundance of these proteins in high vs low MD pair-wise comparisons from breast tissue from 8 individua...

MicroRNAs (miRNAs) are small, non-coding RNAs that regulate gene expression programs and have a critical role in both normal biology and disease. We previously identified microRNA-194 (miR-194) as an important driver of prostate cancer metastasis, although the molecular mechanisms by which it mediates these effects are not well understood. This study aimed to identify target genes and pathways that are responsible for miR-194’s pro-metastatic activity. By integrating tran...

Recent pre-clinical studies indicate that activated progesterone receptor (PR) (particularly the PR-B isoform) binds to oestrogen receptor-α (ER) and reprograms transcription toward better breast cancer outcomes. We investigated whether ER and PR interactions were present in breast and endometrial tumours and associated with clinical parameters including response to endocrine treatments. We developed a proximity ligation assay to detect ER and PR interactions in formalin-...

Introduction: Resistance to endocrine therapy is a major clinical problem in estrogen receptor positive (ER+) breast cancer. The androgen receptor (AR) is expressed in ~90% of all primary ER+ breast cancers and high expression of AR is associated with a better patient outcome in this tumours. However, uncertainty surrounding the role of AR in endocrine resistance is reflected in current clinical trials in which both AR agonists and antagonists are being investigated. Here, we ...

Overexpression of ErbB-2, a member of ErbB family of receptor tyrosine kinases, occurs in 15–20% of breast cancers (BC) and is considered a major oncogenic driver. Despite clinical efficiency of ErbB-2-targeted therapies (e.g. trastuzumab), resistance to said drugs is a major issue. While ErbB-2 is mainly a cell membrane-bound receptor, it can migrate to the nucleus (NErbB-2) where it acts as a transcription factor or coactivator. We revealed that NErbB-2 is a major proli...