Downregulation of expression inhibits malignant progression of breast cancer by targeting the pathway and .

INTRODUCTION

Aberrant circular RNA (circRNA) expression is associated with development of breast cancer. In this study, we aimed to assess the anti-proliferative effect of knockdown on breast cancer cells.

MATERIAL AND METHODS

Tumor and adjacent normal tissues were collected from 35 patients with invasive breast cancer (mean age: 56 years; mean tumor size: 2 cm; 46% patients with TNM I and II stages). The levels of , microRNA ()-, and N-acetylgalactosaminyltransferase 6 () were determined using reverse transcription-quantitative polymerase chain reaction. Cell proliferation and invasion were assessed using cell counting kit-8 and transwell assays, respectively. Cell apoptosis was assessed using flow cytometry. Moreover, the targeting relationships of with and were determined using dual-luciferase reporter and RNA immunoprecipitation assays. Furthermore, tumor growth was observed in an animal model .

RESULTS

We found that expression levels were upregulated in breast cancer tumor specimens and cell lines. Downregulation of inhibited the invasion and proliferation, while enhancing the apoptosis of breast cancer cells. Furthermore, knockdown suppressed tumor growth . Notably, was identified as a downstream target of . Downregulation of suppressed the aggressive behavior of breast cancer cells by targeting . Moreover, was the downstream target of miR-1205. Inhibition of aggravated the malignant behavior of breast cancer cells by increasing expression.

CONCLUSIONS

Our findings suggest that the downregulation of inhibits breast cancer progression, at least in part, by targeting the pathway.