Si e2f3

MCF-7 and MDA-MB-231 (human breast cancer cell lines) were obtained from the Institute of Biochemistry and Cell Biology of the Chinese Academy of Sciences (Shanghai, China). All cells were maintained in Dulbecco's modified Eagle medium (DMEM, Thermo Fisher) supplemented with 10% fetal bovine serum (Gibco, New Zealand) and 1% penicillin/streptomycin (Invitrogen) and cultured at 37°C in a humidified incubator containing 5% CO₂.
The interfering RNA (siRNA) sequences targeting Brachyury: (si-Brachyury#1)-5′-GCUGAACUCCUUGCAUAAG-3′; (si-Brachyury#2)-5′-GCUUAUCAGAACGAGGAGA-3′; the siRNA sequences targeting E2F3: (si-E2F3#1)-5′-GCGGUAUGAUACGUCUCUU-3′; (si-E2F3#2)-5′-GCAUCCACCUCAUUAAGAA-3′; the positive control siRNA: (si-GAPDH)-5′-UGACCUCAACUACAUGGUU-3′ and the negative control siRNA (si-NC)-5′-UUCUCCGAACGUGUCACGU-3′ were purchased from GenePharma (Shanghai, China). Brachyury, E2F3, and the negative control siRNAs were transfected into MCF-7 and MDA-MB-231 cells with Lipofectamine 2000 (Invitrogen, USA) according to the manufacturer's instructions. Sh-Brachyury and empty vector (GenePharma) were stably transfected into MDA-MB-231 cells. Cells were harvested for analysis at 48 h post-transfection.

miR-770-5p mimic (miR-770-5p), miR-770-5p inhibitor (anti-miR-770-5p), siRNA
against E2F3 (si-E2F3), and negative controls (miR-NC, anti-miR-NC, si-NC) were
obtained from GenePharma (China). For overexpression of E2F3, the cDNA sequence
of E2F3 was inserted into pcDNA3.1 empty vector (Invitrogen), termed as
pcDNA3.1-E2F3 (E2F3). All oligonucleotides and plasmids were transfected into
podocytes (2×10⁵ cells/well) with Lipofectamine 2000 reagents
(Invitrogen), according to the operation manual.