Abstract:Objective: To explore the regulation and mechanism of microRNA-27a-3p (miR-27a-3p) on ferroptosis of colorectal cancer cell line HT-29 and SW480. Methods: Colorectal cancer cell lines HT-29 and SW480 were treated with 0, 25 and 5 μmol/L Erastin, respectively. Real-time fluorescence quantitative PCR (qRT-PCR) was used to detect the mRNA expression of solute carrier family 7 member 11 (SLC7A11) in each group and the optimal concentration of Erastin was screened. HT-29 and SW480 cells were divided into siControl group, siSLC7A11-1 group and siSLC7A11-2 group, and transfected with control siRNA, siSLC7A11-1 and siSLC7A11-2, respectively. The cells were co-cultured with 5 μmol/L Erastin for 0, 24, 48 and 72 h to detect the cell proliferation activity and the level of malondialdehyde in the cells at different time points. HT-29 and SW480 cells were divided into miR-NC group, miR-27a-3p group and anti-miR-27a-3p group, respectively, and transfected with miR-NC, miR-27a-3 mimics and miR-27a-3p inhibitors, respectively. The mRNA expression level of SLC7A11 was detected by qRT-PCR, and the luciferase reporter gene assay was used to detect the luciferase activity of SLC7A11 3′UTR sequence (SLC7A11-WT) and mutant sequence (SLC7A11-Mut). The cells were co-cultured with 5 μmol/L Erastin for 0, 24, 48 and 72 h, and the cell proliferation activity was detected at different time points, and the intracellular malondialdehyde level was detected. Results: The mRNA expression of SLC7A11 in colorectal cancer HT-29 and SW480 cells was significantly increased with the increase of Erastin concentration (P<0.01). In colorectal cancer HT-29 and SW480 cells, compared with the siControl group, the cell proliferation activity in siSLC7A11-1 and siSLC7A11-2 groups was significantly increased at 48 h and 72 h (P<0.05), with a significant decrease in malondialdehyde levels (P<0.05). Compared with the miR-NC group, cell proliferation activity in miR-27a-3p group was significantly enhanced (P<0.05), while malondialdehyde levels and luciferase activity of SLC7A11-WT group were significantly decreased (P<0.05 or P<0.01), and luciferase activity of SLC7A11-Mut group showed no significant changes(P>0.05); and the cell viability of anti-miR-27a-3p group was significantly decreased (P<0.01), the level of malondialdehyde and the luciferase activity of SLC7A11-WT were significantly increased (P<0.01), and the luciferase activity of SLC7A11-Mut was not significantly changed (P>0.05). Conclusion: miR-27a-3p may regulate Erastin-induced ferroptosis in colorectal cancer cells by targeting the 3′UTR of SLC7A11 mRNA.
[Key words]colorectal cancer; ferroptosis; miR-27a-3p; solute carriers 7A11