Background:
Hepatocyte nuclear factor 1 homeobox A-
antisense RNA 1 (HNF1A-AS1) is a
long noncoding RNA and controls human
tumor development and progression. However, its expression and role in
breast cancer, the most overwhelmingly occurring
malignancy in women globally, remain poorly illuminated. Materials and Methods: Expression of HNF1A-AS1,
miRNA (miR)-20a-5p, and tripartite motif containing 32 (TRIM32) was detected using quantitative real-time polymerase chain reaction and Western blotting. Cell proliferation, apoptosis, migration, and invasion were measured by cellTiter 96 AQueous one
solution cell proliferation assay kit, flow cytometry, and transwell assays, respectively. Epithelial-mesenchymal transition (EMT) was evaluated by Western blotting, analyzing
E-cadherin,
N-cadherin, and
vimentin expression. Mice xenograft model was generated to investigate
tumor growth in vivo. The target binding among miR-20a-5p, HNF1A-AS1, and TRIM32 was confirmed by dual-
luciferase reporter assay. Results: Expression of HNF1A-AS1 and TRIM32 was upregulated and miR-20a-5p was downregulated in
breast cancer tumors and cell lines. Deletion of HNF1A-AS1 induced cell apoptosis rate, but suppressed cell proliferation, EMT, migration, and invasion in MDA-MB-231 and MCF-7 cells. Furthermore, HNF1A-AS1 downregulation impeded
tumor growth in vivo. Interestingly, miR-20a-5p overexpression elicited the similar suppressive effects in MDA-MB-231 and MCF-7 cells, which was partially reversed by TRIM32 upregulation; besides, miR-20a-5p silencing could abolish the antitumor role of HNF1A-AS1 deletion. Notably, HNF1A-AS1 positively modulated TRIM32 expression through acting as a molecular "sponge" for miR-20a-5p. Conclusions: Knockdown of HNF1A-AS1 suppressed breast
carcinogenesis presumably through targeting miR-20a-5p/TRIM32 axis, suggesting that HNF1A-AS1 might be a promising
therapy target for
breast cancer.