Translational Implications of Dysregulated Pathways and microRNA Regulation in Quadruple-Negative Breast Cancer

Area of Science:

• Oncology
• Molecular Biology
• Genetics

Background:

• Triple-negative breast cancer (TNBC) presents significant therapeutic challenges due to its aggressive nature and poor prognosis.
• Androgen receptor (AR) expression influences breast cancer progression, making AR-negative TNBC a focus for novel classifications.
• Quadruple-negative breast cancer (QNBC) is emerging as a distinct subtype characterized by the absence of HER2, ER, PR, and AR.

Purpose of the Study:

• To define the QNBC tumor subtype and elucidate its unique molecular and clinical characteristics.
• To explore the role of microRNA (miRNA) dysregulation in QNBC pathogenesis and its impact on AR-related pathways.
• To identify knowledge gaps and discuss the clinical and translational implications of QNBC.

Main Methods:

• Review of current literature on breast cancer subtypes, focusing on TNBC and AR expression.
• Analysis of molecular signaling pathways and gene expression profiles associated with QNBC.
• Investigation of microRNA regulatory networks implicated in QNBC development and progression.

Main Results:

• QNBC exhibits distinct molecular, signaling, and expression regulation profiles compared to other breast cancer subtypes.
• MicroRNA networks are significantly dysregulated in QNBC, affecting AR-related targets.
• Dysregulated miRNAs impact key pathways including immune checkpoint inhibitors (ICIs), SKP2, EN1, ACSL4, and EGFR.

Conclusions:

• QNBC represents a unique breast cancer subtype with specific molecular vulnerabilities.
• MicroRNA dysregulation plays a critical role in the pathogenesis of QNBC.
• Further research into QNBC's molecular landscape is crucial for developing targeted therapies and improving patient outcomes.