NTRK1 and melanoma: These melanoma cell lines were tested for their cell states by measuring the protein expression of melanocytic marker MelanA, alongside the dedifferentiation marker AXL, a receptor tyrosine kinase (RTK) associated with the mesenchymal-like and drug-resistant melanoma cell state (Figure 1B) (Müller et al., 2014; Rambow et al., 2019).