Up to now, liver cancer is still hardly diagnose early and treat effectively. Hepatic resection, orthotopic liver transplantation, ablative therapies, chemoembolization and systemic therapies with cytotoxic drugs were still the main treatment strategies for liver cancer . Following the past few years, increasing studies have shown that the molecular phenotype plays more and more imperative functions in the diagnosis and therapeutic reactions of liver cancer patients .
Several datasets about patients’ genomes have been built, which makes researchers recognize the genomic changes between tumor and matched normal tissues. It becomes a crucial step to form a novel and effective identification for prognostic biomarkers on liver cancer outcomes. Meanwhile, accumulating studies have revealed that a variety of biomarkers are emerged as the indicators of prognosis by the analysis of dataset [9–11]. At this study, DEGs between tumor and normal tissues exerted according to a series of analytical processions based on the TCGA database. Especially, we obtained a five-gene signature by means of univariate and multivariate Cox regression analyses. Besides, the risk score was also calculated by this signature, which could be a possible marker to predict the prognosis of patients with liver cancer.
Cell division cycle associated 8 (CDCA8), is a member of the chromosomal passenger complex (CPC) crucial for transmission of the genome during cell division . More studies illustrated that massive expression of CDCA8 was an urgent need to the formation and development of tumor . Loss of CDCA8 could induce the proliferation of defective cell and early embryonic lethality . That reminds us that CDCA8 could be a risk factor in liver cancer because of negative regulatory in the Kaplan–Meier curve at our studies. Nuclear Receptor Subfamily 0 Group B Member 1(NR0B1), as a Protein Coding gene, encodes a protein inferring a DNA-binding domain. The encoded protein acts as a dominant-negative regulator of transcription which is mediated by the retinoic acid receptor. The mutations of NR0B1 would trigger both X-linked congenital adrenal hypoplasia and hypogonadotropic hypogonadism . Ho et al. found that NR0B1 expression is restricted to adrenal-glands, lung and pancreas . In addition, NR0B1, associated with ERα, PR and AR expression , is also a positive prognostic factor in node-negative breast-cancer. It is correlated with smaller tumor-size, earlier disease-stage and increased survival . With the negative survival correlation in this study, NR0B1 maybe a passitive prognostic factor in live cancer. Sperm Protein Associated With The Nucleus On The X Chromosome C (SPANX-C) is a member of the SPANX family, which is located in a gene cluster on chromosome X, whose overexpression has little influence about primary tumor growth in cancer cells, but may be sufficient to determine an invasive phenotypes, including the morphology of their nucleus and the diameter of vessel. Studies of Westcott et al. in vivo/vitro have shown that little SPANX-C expression reduced metastatic behavior of primary tumors and the number of potential metastatic cancer cells . GAGE2A (G Antigen 2A), a protein coding gene, belongs to the GAGE family that code for peptide, containing an open reading frame coding for a protein of 138 amino acids, which are expressed in a significant proportion of melanomas(24%), sarcomas (25%), non-small cell lung cancer(19%), head and neck tumors(19%), and bladder tumors(12%). Mamsen et al. recognized that GAGE gene products could be an important part during early stages of embryonic development . AC018641.1, the Aliases of ENSG00000226468 Gene, was poorly investigated, but along with the further investigations, it could be a prognostic possible marker for cancer detection and therapy.
Future research could investigate the biological characteristics of these five genes for their prognostic value in liver cancer. Besides, we would inform some limitations in this study as followed: the five-gene signature based on dataset analysis in liver cancer was initially useful, but it was not exhaustive. Deeply, it is necessary to have more comprehensive data sets obtained from other databases for supplementary authentication. Particularly, clinical practice would do to verify the five-gene signature mode, and experiments are needed to demonstrate our results. Consequently, this study provides us a guideline that roles of these five genes are related to the prognosis of patients in liver cancer. Although we have only limited knowledge of these five genes, these indicators would be a selecting assist on the cancer progression, monitor and treatment.