In contrast with in vivo results on development of metastases (Table S1) and with data indicating that NRAS mutant clones yield only small colonies in soft agar [20], we found that overexpression of Sema6A in NRASQ61R melanoma clones conferred a strong invasive activity in vitro (P≤0.0001) (Fig. 5A), and capability to generate large colonies in soft agar (P≤0.02) (Fig. 5B). This evidence concerns the gene NRAS and melanoma.