Gentian violet

A total of 500 cells were seeded at single-cell density in 6-well plates with fresh medium with or without cisplatin and allowed to grow for at least a week. Colonies with more than 50 cells were then stained with gentian violet (Solarbio) and counted.

Five hundred cells were seeded in six-well plates at a single-cell density. A blank group and DOX groups treated with or without 1 μg/ml of DOX were prepared for each cell type. Fresh medium was added every 3 days to allow cell growth. Colonies were stained with gentian violet (Solarbio) at 2-3 weeks and colonies with more than 50 cells were counted in each well. The assays were repeated three times.

UNC0638 was purchased from MedchemExpress LLC (Princeton, NJ, USA) and dissolved in dimethyl sulfoxide (DMSO). Dulbecco's modified Eagle's medium (DMEM) and fetal bovine serum (FBS) were purchased from Thermo Fisher Scientific, Inc. (Waltham, MA, USA). 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and low melt point soft agar were purchased from Sigma-Aldrich (Merck KGaA, Darmstadt, Germany). Invasion chambers and matrigel were purchased from BD Biosciences (Franklin Lakes, NJ, USA). Gentian violet was purchased from Beijing Solarbio Science & Technology Co., Ltd. (Beijing, China). The Annexin V-fluorescein isothiocyanate/propidium iodide apoptosis detection kits (cat. no. 556570) were purchased from BD Biosciences. Cell lysis buffer (cat. No. P0013), a BCA protein assay kit (cat. no. P0011) and Primary Antibody Dilution Buffer (cat. no. P0023A) were purchased from Beyotime Institute of Biotechnology (Shanghai, China). Polyvinylidene fluoride (PVDF) membrane and chemiluminescent reagents were obtained from EMD Millipore (Billerica, MA, USA). Antibodies to E-cadherin (20874–1-AP), vimentin (10366–1-AP), Slug (12129–1-AP), Snail (13099–1-AP) and β-actin (60008–1-Ig) were purchased from Proteintech Group, Inc. (Chicago, IL, USA) and diluted at 1:1,000 with Primary Antibody Dilution Buffer (Beyotime, Beijing, China).