Fig. 1
p53β is the most highly expressed p53 isoform in melanoma. A. p53 functional domains, C- and N-terminal isoforms assessed by antibodies in orange. Numbers indicate amino acid position from the start codon. TAD– transactivation domain; PRD– proline-rich domain; DBD– DNA binding domain; NLS– nuclear localisation signal; OD– oligomerisation domain. B. Nuclear and C. cytoplasmic expression of p53 and its isoforms in melanomas stained (brown) with DO-1 (TAp53), KJC40 (Δ40p53), KJC133 (Δ133p53), and KJC8 (p53β). Representative images of low, median, and high expression in 123 melanomas. Associated H-scores displayed next to images. D. Staining of a primary melanoma with DO-1 (TAp53), KJC8 (p53β), KJC40 (Δ40p53), and KJC133 (Δ133p53). The same sample was used in Fig. 1A and B to illustrate low TAp53 and low Δ40p53 staining in the nucleus and cytoplasm. H-scores for each antibody are shown above images. Yellow circles (n = 7) indicate areas used to quantify expression and generate H-scores. Other areas of interest are indicated by blue arrows (normal skin, glands, and infiltrating immune cells). Zoomed in pictures of normal skin, and glands are shown. Scale bars as indicated. Additional samples showing area selection, staining of all antibodies in the same sample, and other structures of interest can be found in Additional file 5. E–G. TAp53 (DO-1), p53β (KJC8), Δ40p53 (KJC40), and Δ133p53 (KJC133) H-Scores measured in nucleus and cytoplasm of E. all melanomas (primary and metastasis combined, n = 123) and F, G primary (n = 71) and metastatic (n = 52) melanomas separately. H. Correlations between nuclear and cytoplasmic p53 isoforms in melanoma with R2 values and p-values of the linear regression displayed. Significance determined through Friedman test (matched E) or Kruskal–Wallis test (unmatched F & G), corrected for multiple comparisons with Dunn’s multiple comparisons test. For E only some p-values are displayed, with all p-values shown in the adjacent table. *p < 0.05, **p < 0.01; ***p < 0.001; ****p < 0.0001