FOS and neoplasm: For example, some in vitro studies have indicated that UC-MSCs increase the expression of proliferating cell nuclear antigen (PCNA) [96], induce the proliferation promoting genes like EPGN/MZT2A, downregulate transcription factors associated with the suppression of tumor development such as TAL1/FOS/EGR1/KLF10, which stimulates different tumor populations [97].