Background: Breast cancer is a malignancy with no clearly identified prognostic factors for diagnosis. Studies have preliminarily found that lncRNAs are related to breast cancer metastasis, however, the clinical predictive significance of lncRNAs is still elusive.In this study, we evaluated the diagnostic value of long non-coding RNA (lncRNA UCA1,CCAT2, ANCR) on postoperative metastasis of breast cancer as well as the possible mechanism involving the EMT.
Methods: We investigated lncRNA ANCR, UCA1,CCAT2 that associated with breast cancer metastasis risk in a population-based nested case-control study. Metastasis cases were identified by clinical diagnostic criteria in approximately 103 cases in the Cancer Institute of Southwest Medical University during 2013-2020. At the same time, the control group (metastasis-free) was selected according to the 1:1 pairing principle in this cohort (n=103, the matching condition was age±3 years, the operation time within the same month, and the treatment plan both are modifed radical mastectomy) The mRNA of lncRNA( UCA1,CCAT2, ANCR) expression was determined by Real-time PCR. The expression of E-cadherin, N-cadherin, and vimentin proteins was detected by Western blot. The migration and invasion of transfected cells were determined by the Transwell assay.
Results: lncRNA ANCR, UCA1, CCAT2 was significantly up-regulated in breast cancer cells and postoperative metastasis of breast cancer.CCAT2 (OR=1.024, 95% CI: 1.010, 1.039), UCA1(OR=1.025, 95% CI: 1.011, 1.039),ANCR(OR=1.055, 95% CI:1.001, 1.111)was the risk factor for postoperative metastasis of breast cancer. Furthermore , we used the ROC curve to detect the optimal critical values of CCAT2, UCA1, ANCR , the risk of metastasis in the CCAT2 high expression group was 2.297 times that of the low expression group (OR=2.297, 95% CI:1.427 ~ 3.695, P< 0.05). The risk of metastasis in the UCA1 high expression group was 2.032 times that of the low expression group (OR=2.032, 95% CI 1.282 ~ 3.218, P<0.05). We further observed that lncRNA UCA1, CCAT2, ANCR was down-regulated in MDA-231 cells by 48 h of siRNA transfection. LncRNAs UCA1, CCAT2, ANCR silencing significantly decreased the percentage of migration and invasion cells, down-regulated N-cadherin, and up-regulated E-cadherin and vimentin in MDA-231 cells.
Conclusions: Our data suggested that lncRNA CCAT2 , UCA1,ANCR was a novel molecule involved in postoperative metastasis of breast cancer, which has predictive value in patients with breast cancer metastasis.