PTGFRN and hepatocellular carcinoma: Although the remained genes filtered out in the present study such as Akr1d, Apoa5, Crp, Cxcl12, Kcnk5, Ngfr, Rnf152, Tmem25, Ptgfrn, and Slc6a8 are understudied, the same expression patterns of these genes in mouse and human HCC indicate their important roles in hepatocarcinogenesis and provide a primary reference and potential targets for further investigations.