There is no clear treatment guideline or individualized treatment plan for triple-negative breast cancer (TNBC). The aim of this study was to investigate more effective targets for TNBC-targeted therapy. MDA-MB-231 and BT549 cell lines were used to explore the function of LINC00649 on the proliferation, invasion, and migration of TNBC cells. A mice subcutaneous tumor model and a pulmonary metastasis model was established to identify the role of LINC00649 on the growth and metastasis of TNBC in vivo. LINC00649 was found to be a key molecule involved in the occurrence and development of TNBC by screening of public databases and detection of TNBC clinical samples. LINC00649 increased hypoxia-inducible factor 1α (HIF-1α) mRNA stability and protein expression by interacting with the nuclear factor 90 (NF90)/NF45 complex. In vitro, interference with LINC00649 inhibits MDA-MB-231 and BT549 cell proliferation, migration, and invasion, and the addition of HIF-1α revised this effect. In vivo experiments showed that LINC00649 promoted the growth and metastasis of TNBC. We demonstrated that LINC00649 interacts with the NF90/NF45 complex to increase the mRNA stability of HIF-1α and up-regulate HIF-1α expression, thereby inducing the proliferation, invasion, and migration of TNBC cells as well as tumor growth and metastasis.
Keywords: HIF-1α; NF90/NF45; Triple-negative breast cancer; lncRNA LINC00649.