Journal: Nature
Article Title: Failure of human rhombic lip differentiation underlies medulloblastoma formation
doi: 10.1038/s41586-022-05215-w
Figure Lengend Snippet: a, PRDM6 expression in CBFA2T2 mutant (red) and CBFA2T2 WT (grey) G3 and G4 MB samples demonstrates that enhancer hijacking mediated PRDM6 expression is largely limited to CBFA2T2 WT cases. b, Density of regions of chromosomal gain and loss along human chromosome 16q in G3 and G4 MB cases, demonstrating that deletions are biased towards the telomeric end of 16q, the location of known drivers, particularly CBFA2T3. c, CBFA2T3 expression differences between samples with and without CBFA2T3 deletions, split by subgroup. Statistical significance was assessed using Kruskal-Wallis rank-sum test (FDR < 0.05), *** p < 0.0005, G3, p = 2.88e−05; G4, p = 2.60e-09. G3, n = 112; G4, n = 206. CBFA2T3 is a copy-number responsive tumor suppressor gene in G4 MB. d, IGV analysis showing focal deleted region in two G4 MB samples MB-0364 and MB-0559. MB-0364, which is the minimal common deleted region (MCDR) on 16q in G3 and G4 MB, though does not quite achieve statistical significance in the GISTIC analysis. MB-0559 is the MCDR achieving statistical significance in GISTIC analysis. CBFA2T3 is identified with a red box. e, Cartoon illustrating the MCDR concept. f, Expression differences between copy neutral or hemizygously deleted G3 and G4 MB samples for genes within the MB-0364 MCDR on chr16q24.3. Statistical significance was assessed using two-sided Mann-Whitney U tests with FDR adjustment, * p < 0.05, *** p < 0.0005. Deletion, n = 86; Neutral, n = 232. e, Expression differences between copy neutral or hemizygously deleted G3 and G4 MB samples for genes within the MB-0559 MCDR on chr16q24.3. Statistical significance was assessed using two-sided Mann-Whitney U tests with FDR adjustment, * p < 0.05, *** p < 0.0005. Deletion, n = 86; Neutral, n = 232. A full list of p values for genes presented in (f) and (g) can be found in Supplementary Data Table 1. h, CBFA2T2 (left) and CBFA2T3 (right) expression in SHH, G3, and G4 MB by bulk RNAseq. Statistical significance was assessed by Kruskal-Wallis rank-sum test (FDR < 0.05), * p < 0.05, *** p < 0.0005. For CBFA2T2: SHH-G3, p = 2.29e−47; SHH-G4, p = 4.42e−73; G3-G4, p = 0.035. For CBFA2T3: SHH-G3, p = 7.10e−42; SHH-G4, p = 1.13e−46; G3-G4, p = 0.61. G3, n = 219; G4, n = 326; SHH, n = 250. While CBFA2T2 and CBFA2T3 are recurrently targeted and have low expression in G3 and G4 MB, high expression of both genes and an absence of alterations are observed in SHH MB. CBFA2T2 and CBFA2T3 likely have different roles in SHH MB compared to G3 and G4 MB. For c, f, g, and h box plots show the median and interquartile range, and whiskers show the data range. Points outside this range are outliers and are plotted individually.
Article Snippet: Increased CBFA2T2 expression was confirmed by qPCR and immunoblotting (CBFA2T2, A303–593A-M, Bethyl Laboratories at 1:500, with β-actin, Sigma-Aldrich, A2228, mouse, at 1/1000 used as a loading control).
Techniques: Expressing, Mutagenesis, MANN-WHITNEY