Most of these GFP cells (68 ± 5%) co-stained for Calretinin (Figure 7F), showing that myxoma-derived c-kitpos/CD45neg/CD31neg CSCs differentiated in the typical myxoma ‘leipidic’ cells in vivo. In striking contrast, the c-kitpos/CD45neg/CD31neg hCSCs from the normal controls were unable to form any palpable mass or any histological detectable tumour in any of the injected mice, independently of the cell number administered (Figure 7C and G). Here, CALB2 is linked to myxoma.