Research Paper Volume 14, Issue 7 pp 3105—3128

Figure 2. Biological functions of circ_6014 in breast cancer cells. (A, B) Expression levels of circ_6014 in both MDA-MB-231 and MCF-7 cells after transfection with the second small interfering RNA and circ_6014 plasmids. (C, D) MTT assays of both cell lines showed that the proliferation was inhibited (C) or promoted (D) with decreased or overexpressed levels of circ_6014. (E, F) Colony formation assays showed that the down- or upregulated level of circ_6014 suppressed (E) or enhanced (F) the cellular colony-forming capacity. (G, H) Transwell assays showed that migration and invasion were suppressed (G) by downregulating circ_6014 expression and promoted (H) by upregulating circ_6014 expression. (I, J) The percentage of cell cycle distribution of the G0/G1, S, and G2/M phases with down- or upregulation of circ_6014 expression in both breast cancer cells; circ_6014 could affect the progression of G0/G1 phase. (K) Protein levels of CDK2, CCNE1, CDK4, CDK6, CCND1, and PCNA in MDA-MB-231 and MCF-7 cells decreased after decreasing the expression of circ_6014. (L) Columns were used to quantify the cell cycle protein expression levels in (K) relative to β-actin. (M) Protein levels of CDK2, CCNE1, CDK4, CDK6, CCND1, and PCNA in MDA-MB-231 and MCF-7 cells increased after increasing the expression of circ_6014. (N) Columns were used to quantify the cell cycle protein expression levels in (M) relative to β-actin. ^*p < 0.05, ^**p < 0.01, ^***p < 0.001.