Updated publication reference for PubMed record(s): 32461585. Amoeboid and mesenchymal migration of cancer cells both contribute to metastatic spreading of tumors. To characterize proteome changes underlying the different migratory modes, we performed mass spectrometry profiling of HT1080 fibrosarcoma cells undergoing mesenchymal-amoeboid transition induced by either doxycycline-inducible constitutively active RhoA or dasatinib treatment. Cells were kept in three-dimensional collagen gels with or without induction for 48 hours, lysed and processed for mass spectrometry analysis. In case of the inducible RhoA system, we also performed parallel two-dimensional experiments with cells on top of a dense layer of collagen (it was not feasible with dasatinib treatment).