Roles of MSX transcription factors in cancer and the known mechanism. Regulation of the expression of MSX transcription factors including downstream transcription factors of signaling pathways, individual transcription factors, gene mutation, DNA methylation, histone acetylation and deacetylation, ubiquitination and degradation, single nucleotide polymorphism or microRNA regulation may up- or down-regulate the expression of MSX transcription factors. Regulation of transcriptional activity: depending on the environment, MSX transcription factors function as transcriptional activators or repressors: (I) they may recruit co-regulators including Miz1, Dlx5, SHARP, MINT, RBM15, TBP, PAX3, YB1/p32, H1b, H1C to form transcriptional complexes and (II) post-translational modifications such as SUMOylation may affect transcription, resulting in different endings. By targeting different genes, MSX transcription factors are involved in: (I) cell proliferation (cyclin D1, cyclin D3, cyclin E, cyclin-dependent kinase 4, c-jun, Rb, NKX3-1); (II) cell apoptosis (Cip1, ERK, BIRC5, caspase 3, BCL2, survivin, N-cadherin, MIR17HG); (III) cell invasion (E-cadherin, vimentin, N-cadherin, β-catenin, Twist1, KIFs); (IV) cell metastasis (BSP, ZEB1); (V) cell differentiation (NEUROD1); (VI) tumor stemness (MyoD, Myf5, SOX2); (VII) drug resistance (ABCG2, SOX2); (VIII) angiogenesis (VEGF).