👤 Sei Kakinuma

The mechanism of hepatocarcinogenesis after sustained virological response (SVR) in hepatitis C virus (HCV) patients is unclear. We compared gene profiles of hepatocellular carcinoma (HCC) between HCV-SVR, steatotic liver disease (SLD), and HCV-non-SVR patients. This study analyzed 126 resected HCCs from patients with HCV and SLD, classifying them as HCV-SVR (n = 22), HCV-non-SVR (n = 56), and SLD (n = 48). Deep sequencing of 2910 hotspots in 55 cancer-related genes was conducted to examine mutations and copy number variations in both cancerous and background liver tissues. The HCV-SVR group comprised more patients who consumed alcohol (45.5% vs. 15.7%, p = 0.008), were obese (54.5% vs. 17.9%, p = 0.002), and had dyslipidemia (18.2% vs. 3.6%, p = 0.029) and hyperuricemia (18.2% vs. 3.6%, p = 0.029) than the HCV-non-SVR group. Mutational profiling of the HCV-SVR HCC showed significantly lower alteration rates of AXIN1 (13.6% vs. 42.9%, p = 0.016), ARID2 (9.1% vs. 39.3%, p = 0.013), and TP53 (9.1% vs. 32.1%, p = 0.030) than HCV-non-SVR patients. Compared with HCV-non-SVR-HCC, SLD-HCCs showed significantly lower rates of TERT promoter mutations (62.5% vs. 85.7%, p = 0.004), ARID2 alterations (12.5% vs. 39.3%, p = 0.003), and AXIN1 alterations (12.5% vs. 42.9%, p = 0.002). HCV-SVR/MASH/MASLD/ALD-HCC had significantly lower alteration rates of the Wnt/β-catenin (41.4% vs. 60.7%, p = 0.048) and chromatin remodeling pathways (27.1% vs. 48.2%, p = 0.026) than HCV-non-SVR-HCC. HCV-SVR HCC is linked to alcohol use and metabolic diseases, showing a mutational profile similar to SLD-HCC. Show less

Genetic alterations in specific genes are critical events in carcinogenesis and hepatocellular carcinoma (HCC) progression. However, the genetic alterations responsible for HCC development, progression, and survival are unclear. We investigated the essential difference in genetic alterations between HCC and adjacent non-HCC tissues using next-generation sequencing technology. We found recurrent mutations in several genes such as telomerase reverse transcriptase (TERT; 65% of the total 104 HCCs), TP53 (38%), CTNNB1 (30%), AXIN1 (2%), PTEN (2%), and CDKN2A (2%). TERT promoter mutations were associated with older age (p = 0.005), presence of hepatitis C virus (HCV) infection (p = 0.003), and absence of hepatitis B virus (HBV) infection (p < 0.0001). In hepatitis B surface antigen (HBs Ag)-positive HCC without TERT promoter mutations, HBV integration into TERT locus was found in 47% patients and was mutually exclusive to TERT promoter mutations. Most (89%) HBV integrants were in the HBx region. TP53 mutations were associated with HBV infection (p = 0.0001) and absence of HCV infection (p = 0.002). CTNNB1 mutations were associated with absence of HBV infection (p = 0.010). Moreover, TERT promoter mutation was significantly associated with shorter disease-free survival (p = 0.005) and poor overall survival (p = 0.024). Gene alterations in TERT promoter, TP53, CTNNB1, and HBV integration were closely associated with HCC development, and mutations in TERT promoter are related to poor prognosis. These results are useful for understanding the underlying mechanism of hepatocarcinogenesis, diagnosis, and predicting outcomes of patients with HCC. Show less

The molecular basis by which proteins are transported along cytoskeletal tracts from the trans-Golgi network (TGN) to the cell periphery remains poorly understood. Previously, using human autoimmune sera, we identified and characterized a TGN protein, p230/Golgin-245, an extensively coiled-coil protein with flexible amino- and carboxyl-terminal ends, that is anchored to TGN membranes and TGN-derived vesicles by its carboxyl-terminal GRIP domain. To identify molecules that interact with the flexible amino-terminal end of p230, we used this domain as bait to screen a human brain cDNA library in a yeast two-hybrid assay. We found that this domain interacts with the carboxyl-terminal domain of MACF1, a protein that cross-links microtubules to the actin cytoskeleton. The interaction was confirmed by co-immunoprecipitation, an in vitro binding assay, double immunofluorescence images demonstrating overlapped localization in HeLa cells, and co-localization of FLAG-tagged constructs containing the interacting domains of these two proteins with their endogenous partners. Expression in HeLa cells of FLAG-tagged constructs containing the interacting domains of p230 and MACF1 disrupted transport of the glycosyl phosphatidyl inositol-anchored marker protein conjugated with yellow fluorescent protein (YFP-SP-GPI), while trafficking of the transmembrane marker protein, vesicular stomatitis virus glycoprotein conjugated with YFP (VSVG3-GL-YFP), was unaffected. Our results suggest that p230, through its interaction with MACF1, provides the molecular link for transport of GPI-anchored proteins along the microtubule and actin cytoskeleton from the TGN to the cell periphery. Show less