Background:
Breast cancer is one of the most prevalent
cancers that often occur in females.
Long noncoding RNA differentiation antagonizing nonprotein coding
RNA (DANCR) has been involved in the pathogenesis of various
tumors, including
breast cancer. This study aimed to investigate the role and underlying mechanism of DANCR in
breast cancer. Materials and Methods: The level of DANCR was detected in
breast cancer tissues and cells by quantitative real-time polymerase chain reaction (qRT-PCR). Cell viability was evaluated by the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium
bromide assay. Cell apoptosis was assessed using flow cytometry. Cell migration and invasion were estimated by the Transwell assay. The relationship between DANCR, miR-4319, and
vesicle-associated membrane protein-associated
protein B (VAPB) was confirmed by bioinformatic analysis and dual-
luciferase reporter assay. The level of microRNA-4319 (miR-4319) was tested by qRT-PCR. The expression of VAPB was measured by qRT-PCR or Western blot assay. Results: DANCR and VAPB were upregulated, while miR-4319 was downregulated in
breast cancer tissues and cells. Knockdown of DANCR hindered proliferation, migration, and invasion and promoted apoptosis of
breast cancer cells. DANCR knockdown inhibited
breast cancer development through regulating miR-4319. Inhibition of miR-4319 restrained
breast cancer cell progression by targeting VAPB. Moreover, DANCR regulated VAPB expression by sponging miR-4319 in
breast cancer cells. Conclusion: DANCR facilitated
breast cancer cell progression through regulating the miR-4319/VAPB axis, indicating that DANCR might be a potential
biomarker and therapeutic target for
breast cancer treatment.