ABSTRACT: Background:Liver -cell proliferation occurs in hepatocellular carcinoma (HCC) and liver regeneration (LR). The development and progression of HCC and LR have many similar molecular pathways with very different results. In simple terms, LR is a controllable process of organ recovery and function reconstruction, whereas liver cancer is uncontrollable. Do they share common key pathways and genes? Methods:In this study, the dynamic transcriptome profile at ten time points (0, 2, 6, 12, 24, 30, 36, 72, 120, and 168 hours) during LR in rats after two-thirds hepatectomy and eight stages (normal, cirrhosis without HCC, cirrhosis, low-grade dysplastic, high-grade dysplastic, and very early, early advanced, and very advanced HCC) representing a stepwise carcinogenic process from preneoplastic lesions to end-stage HCC were analyzed in detail. A variety of bioinformatic methods, including MaSigPro, weighted gene-coexpression network analysis, and spatial analysis of functional enrichment, were used to analyze, elucidate, and compare similarities and differences between LR and HCC formation. Results:Key biological processes and genes were identified. From the comparison, we found that cell proliferation and angiogenesis were the most significantly dysregulated processes shared by LR and HCC. The pattern of cell-proliferation-related gene expression in progression stage during LR is similar to the transition process from dysplasia to early-stage HCC. LR and HCC showed different expression patterns as a whole. Some key genes, including FYN, XPO1, FOXM1, EZH2, and NRF1, were identified as playing critical roles in both LR and HCC. Conclusion:These findings could contribute to revealing the molecular mechanism of development and regulation mechanism of normal and abnormal proliferation, which could provide new ideas and treatment methods for regenerative medicine, oncological drug development, and oncological treatment.