AKR1C1 and hepatocellular carcinoma: Mounting evidence reveals that AKR1C1 is volved in a variety of cancers, including hepatocellular carcinoma, lung cancer, gastric cancer, and cervical cancer, and the over-expression of AKR1C1 has been found to be associated with carcinogenesis (Hsu et al., 2001; Ji et al., 2004; Fukumoto et al., 2005; Woenckhaus et al., 2006; Seo et al., 2007; Chang et al., 2009; Chien et al., 2009; Rizner, 2012; Matsunaga et al., 2014).