Mir nc or anti nc

Normal colon FHC cells and four CRC cell lines (SW480, HCT116, SW620, LoVo) were purchased from COBIOER (Nanjing, China) and cultured in Dulbecco’s modified eagle medium (DMEM; Invitrogen, Carlsbad, CA, USA) supplemented with 10% fetal bovine serum (FBS, Gibco, Carlsbad, CA, USA), 100 U/mL penicillin and 100 μg/mL streptomycin at 37°C under a humidified atmosphere containing 5% CO₂.
Short hairpin RNA (shRNA) targeting circ_0000512 (sh-circ#1, sh-circ#2 and sh-circ#3) and corresponding negative control (sh-NC), RUNX1 overexpression vector (RUNX1) and empty vector (vector) were purchased from Genechem (Shanghai, China). MiR-296-5p mimic or inhibitor (miR-296-5p or anti-miR-296-5p) and their negative controls (miR-NC or anti-NC) were synthesized by GenePharma (Shanghai, China). HCT116 and SW620 cells were transfected with these oligonucleotides (50 nM) or vectors (2 μg) by Lipofectamine 3000 reagent (Invitrogen).

Human NK cell line NK-92, mouse NK cell line LNK, human LA cell line A549, and 293T cells were obtained from American Tissue Culture Collection (ATCC, Manassas, VA, USA). In this study, all cells were grown in RPMI-1640 (Gibco, Carlsbad, CA, USA) containing 10% fetal bovine serum (Gibco), 1% penicillin, and streptomycin (Invitrogen, Carlsbad, CA, USA) at 37℃ in an incubator with 5% CO₂.
To activate NK-92 or LNK cells, 20 ng/mL interleukin-2 (IL-2, Gibco) was introduced into cells for 24 h. SHMT1 overexpression vectors (SHMT1) cloned into pcDNA, miR-218-5p mimics (miR-218-5p), miR-218-5p inhibitor (anti-miR-218-5p), and negative control (miR-NC or anti-NC) were obtained from GenePharma (Shanghai, China). Transfection was performed in NK-92 or LNK cells using Lipofectamine 2000 (Invitrogen) according to the manufacturer's protocol.

The normal breast epithelial cell line MCF-10A and BC cell lines MCF-7, MDA-MB-231, BT20, T47D, and SKBR3 were obtained from American Tissue Culture Collection (ATCC, Manassas, VA, USA). All cells were cultured in Dulbecco's Modified Eagle Medium (Gibco, Carlsbad, CA, USA) containing 10% fetal bovine serum (Gibco), 1% penicillin, and streptomycin (Invitrogen, Carlsbad, CA, USA) at 37℃ in 5% CO₂ during the study.
PTEN overexpression vectors (PTEN) were cloned into pcDNA by GenePharma (Shanghai, China). MiR-182-5p mimics (miR-182-5p), miR-182-5p inhibitor (anti-miR-182-5p), and negative control (miR-NC or anti-NC) were obtained from GenePharma. To investigate the effect of miR-182-5p and PTEN on cell proliferation and invasion, transfection was performed in MCF-7 and MDA-MB-231 cells using Lipofectamine 2000 (Invitrogen) according to the manufacturer's protocol.