LINC00982 Inhibits the Proliferation, Migration, and Invasion of Breast Cancer Cells Through the miR-765/DPF3 Axis

Breast cancer (BC) is one of the most frequently occurring malignant tumors in female adults. The long intergenic nonprotein coding RNA 00982 (LINC00982) has been regarded as a cancer suppressor in several human cancers. However, the function and the underlying mechanisms of LINC00982 have not been studied in BC. The present study found that LINC00982 was significantly downregulated in BC tumor tissues, and the low LINC00982 level predicts a poor prognosis of BC. Through the overexpression and suppression of LINC00982 in two BC cell lines, we found that LINC00982 could inhibit cell proliferation, migration, and invasion by suppressing the activity of the signal transducer and activator of transcription 3 (STAT3)/nuclear factor kappa B (NF-κB) signal pathway. Furthermore, luciferase reporter assay has been used to verify that LINC00982 functions as a molecular sponge for miR-765, which could target DPF3. The relative expression of miR-765 decreased with LINC00982 overexpressing, and DPF3 increased at the same time. In addition, the suppression of cell malignant phenotype caused by overexpression of LINC00982 can be reversed by inhibition of DPF3. To verify the function of LINC00982 in vivo, the BC cells were implanted in nude mice and the results suggested the tumor growth and malignant phenotype were suppressed by LINC00982. In this study, we prove that LINC00982 regulates the growth and development of BC through STAT3/NF-κB signal pathway, mediated by the miR-765/DPF3 axis. LINC00982 may function as a target molecule to take part in the prognosis and therapy of BC.