HNRNPD and hepatocellular carcinoma: For functional validation of butyrate-induced upregulation of AUF-1, we studied hepatic expression of a known classic target of AUF-1 sphingosine kinase1 (spkh1) (Sobue et al., 2008), responsible for cellular proliferation (Sobue et al., 2008) and a prognostic marker for hepatocellular carcinoma (HCC) (Cai et al., 2017).