USP22 and neoplasm: Importantly, increased USP22 expression is closely associated with neurodegenerative diseases, carcinogenesis, and poor patient survival in a wide range of tumor types (Glinsky et al, 2005; Liu et al, 2010; Liu et al, 2011; Yang et al, 2011; Zhang et al, 2011; Piao et al, 2012; Li et al, 2012b; Wang et al, 2013; Liang et al, 2014; Ning et al, 2014; Ji et al, 2015; Tang et al, 2015; Wang et al, 2015).