Fig. 2: Chaetocin exhibits anti-tumor effects on NB cells both in vitro and in vivo.

A CCK-8 analysis identified the IC50 values of SK-N-SH and SK-N-BE (2) after chaetocin treatment for 48 h. The cell viability rate was calculated as (ODtest − ODblank)/(ODcontrol − ODblank)*100. The Graphpad software was used to fit the growth curve and calculate the IC50 value. B Colony formation analysis of NB cells after chaetocin treatment with different concentrations for 48 h, and the colonies of SK-N-SH (after 14 days) and SK-N-BE (2) (after 12 days) were collected and stained with crystal violet. C, D Wound healing and transwell assay illustrated the migration abilities of NB cells after treatment with chaetocin for 24 h. E Apoptosis analysis by flow cytometry in NB cells after treated with chaetocin for 48 h. F Cell cycle distribution changes caused by chaetocin treatment for 12 h. G IF staining of H3K9me3 in NB cells located in nucleus with or without chaetocin treatment for 48 h. H WB analysis illustrated levels of the H3K9me3 protein after chaetocin treatment for 48 h. I Pictures of harvested tumors in NOD SCID mice in the control (n = 5) or chaetocin (n = 5) treatment group. J Tumor volumes of NB xenograft models with control (n = 5) or chaetocin treatment (n = 5). K Tumor weight of tumors from the control (n = 5) or the chaetocin group (n = 5). L Body weights of NB-bearing mice after chaetocin treatment (n = 5) or not (n = 5). M H&E and IHC analysis of H3K9me3 in tumors from the control or the chaetocin group. Shown is one representative picture of indicated groups (n = 5 for each group). B–E, G, J The one-way ANOVA with multiple comparisons to the control was performed for statistical analysis. F, H The two-way ANOVA was performed for statistical analysis. K The t-test was performed for statistical analysis. The experiments were repeated three times with similar results. Data were shown as the mean ± SEM, ns: non significance, *p < 0.05, **p < 0.01, ***p < 0.001, ****p < 0.0001.