[[TP53]] [[point mutation]]s are found in 50% of all [[cancer]]s and seem to play an important role in [[cancer pathogenesis]]. Thus, [[human induced pluripotent stem cell]]s (hiPSCs) overexpressing mutant TP53 are a valuable tool for the generation of [[in vitro]] [[model]]s of [[cancer stem cell]]s or for [[in vivo]] [[xenograft]] models. Uhlmann et al. from the [[University Hospital of Düsseldorf]], described a [[protocol]] for the alteration of [[gene expression]] in hiPSCs via [[overexpression]] of a mutant form of the [[TP53]] ([[R249S]]) gene using [[lentiviral transduction]]. A high amount of TP53 protein is detected 1 week after transduction and antibiotic selection. Differentiation of transduced hiPSCs gives insight into a better understanding of cancer formation in different tissues and may be a useful tool for genetic or pharmacologic screening assays. Basic Protocol 1: Production and concentration of third-generation lentivirus Support Protocol 1: Cloning of gene of interest into modulation vector Support Protocol 2: Preparation of DMEM GlutaMAX™ with 10% fetal bovine serum and 1% penicillin-streptomycin Basic Protocol 2: Transduction of human-induced pluripotent stem cells and selection of positively transfected cells Support Protocol 3: Preparation of Matrigel® -coated plates Support Protocol 4: Preparation of mTeSR™1 medium ((Uhlmann C, Kuhn LM, Tigges J, Fritsche E, Kahlert UD. Efficient Modulation of TP53 Expression in Human Induced Pluripotent Stem Cells. Curr Protoc Stem Cell Biol. 2020 Mar;52(1):e102. doi: 10.1002/cpsc.102. PubMed PMID: 31883435. )).