A Prospective Tumour Marker for Breast Cancer: YWHAB and Its Role in Promoting Oncogenic Phenotypes.

Background: YWHAB (14-3-3 Beta) was found in the secretome of miR-526b and miR-655 overexpressed breast cancer (BRCA) cell lines. The potential of YWHAB as a therapeutic target or biomarker for BRCA is investigated here.

Methods: After YWHAB was knocked down with siRNA, BRCA cell lines were used for in vitro assays (proliferation, migration, epithelial-to-mesenchymal transition).

Breast cancer cell secretome analysis to decipher miRNA regulating the tumor microenvironment and discover potential biomarkers.

MicroRNA (miRNA/miR) 526 b- and miR655-overexpressed tumor cell-free secretions regulate the breast cancer tumor microenvironment (TME) by promoting tumor-associated angiogenesis, oxidative stress, and hypoxic responses. Additionally, premature miRNA (pri-miR526b and pri-miR655) are established breast cancer blood biomarkers. However, the mechanisms of how these miRNAs regulate the TME has yet to be investigated.

miR526b and miR655 Induce Oxidative Stress in Breast Cancer.

In eukaryotes, overproduction of reactive oxygen species (ROS) causes oxidative stress, which contributes to chronic inflammation and cancer. MicroRNAs (miRNAs) are small, endogenously produced RNAs that play a major role in cancer progression. We established that overexpression of miR526b/miR655 promotes aggressive breast cancer phenotypes.

Mir526b and Mir655 Promote Tumour Associated Angiogenesis and Lymphangiogenesis in Breast Cancer.

MicroRNAs (miRNAs) are small endogenously produced RNAs, which regulate growth and development, and oncogenic miRNA regulate tumor growth and metastasis. Tumour-associated angiogenesis and lymphangiogenesis are processes involving the release of growth factors from tumour cells into the microenvioronemnt to communicate with endothelial cells to induce vascular propagation. Here, we examined the roles of cyclo-oxygenase (COX)-2 induced miR526b and miR655 in tumour-associated angiogenesis and lymphangiogenesis.

Prostaglandin E2 promotes embryonic vascular development and maturation in zebrafish.

Prostaglandin (PG)-E2 is essential for growth and development of vertebrates. PGE2 binds to G-coupled receptors to regulate embryonic stem cell differentiation and maintains tissue homeostasis. Overproduction of PGE2 by breast tumor cells promotes aggressive breast cancer phenotypes and tumor-associated lymphangiogenesis.