Cell proliferation kit

5 × 10³ TNBC cells were planted in a 96-well plate per well at 37 °C for 48 h. Then, 5 mg/mL 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyltetrazolium bromide (MTT) solution (10 μL/well) was added and incubated at 37 °C for 4 h. 100 μL dimethyl sulfoxide was used to dissolve crystallization. Absorbance at the wavelength of 490 nm was detected by automatic enzyme marker (Multiskan GO, Thermo, USA). For EdU assay, 5 × 10⁴ TNBC cells were seeded in 24-well plate per well; cell Proliferation Kit (Beyotime Biotechnology, Nanjing, China) was applied to detect cell proliferation by fluorescence microscope (X-73; Olympus, Tokyo, Japan).

Primary myoblasts were labeled with EdU for 2 h (Cell Proliferation Kit, Cat# C0075S, Beyotime) followed by fixation and permeabilization with 0.2% Triton X‐100.

Cell viability was detected using a cell proliferation kit (Beyotime Institute of Biotechnology). Cells were seeded into 96-well plates at a density of 2000 cells/well. Following transfection with si-Linc 1#, 2#, 3# and a negative control (si-NC), 20 μl of MTT reagent was added to each well and then incubated for 4 h at 37 °C. The cell proliferation curves were measured at a wavelength of 570 nm at each indicated time point. Experiments were performed in triplicate.
For the colony formation assay, ~200 cells were cultured in 6-well plates after transfection for 48 h and maintained in 10% fetal bovine serum (FBS) at 37 °C for 12 days. After this, the colonies were fixed with 4% polyoxymethylene and stained with a hematoxylin and eosin (H&E) Staining Kit (Beyotime Institute of Biotechnology). The colony formation ratio was manually calculated.