Fig. 4

Differences in onset and progression of melanoma tumor between optimistic and pessimistic zebrafish.Differences in onset and progression of melanoma tumor between judgment bias-related phenotypes exposed to the effects of chronic stress (n = 7–11 per experimental group: optimists control, pessimists control, optimists stress, and pessimists stress). A Representative image of juvenile transgenic zebrafish harboring melanoma tumor and its corresponding histological section; B Performance of juvenile melanoma zebrafish and their WT siblings in the judgment bias paradigm (n = 32 each group). Different letters indicate significant differences between the experimental groups (transgenic fish and WT) for each Treatment (P, N, A) following planned comparisons tests. Data are expressed as mean ± s.e.m.; C JBS of juvenile melanoma zebrafish and their WT siblings. Different letters indicate significant differences between experimental groups (transgenic fish and WT); D Melanoma occurrence over time in juvenile transgenic fish (OC optimists control; PC pessimists control; OS optimists stress; PC pessimists stress). Asterisks indicate statistically significant differences between the experimental groups at each sampling point: *p < 0.05, **p < 0.01, ***p < 0.001; E Tumor fraction (%) in the different experimental groups of juvenile melanoma fish. Different letters indicate significant differences between the experimental groups following planned comparisons tests. F PCNA-positive tumor cells (%) in the different experimental groups of juvenile melanoma fish. Different letters indicate significant differences between the experimental groups following planned comparisons tests.