Myeloid-derived suppressor cells (MDSCs) could have important roles in immune regulation, and MDSCs can be induced in patients with various malignant tumors. The immune-suppressive functions of MDSCs in hepatocellular carcinoma (HCC) patients have not been clarified. Therefore, we tried to analyze the biological significance of MDSCs in HCC patients. We quantified PD-L1+MDSCs of HCC patients in various conditions by using multi-color flow cytometry analysis. PBMCs from HCC patients contained significantly higher percentages of PD-L1+MDSCs in comparison to those from healthy subjects (p < 0.001). The percentages of PD-L1+MDSCs were reduced by curative treatment for HCC (p < 0.05), and the percentages of PD-L1+MDSCs before treatment were inversely correlated with disease-free survival time. After we cocultivated PBMCs and several liver cancer cell lines in a transwell coculture system, the percentages of PD-L1+MDSCs were significantly increased compared with control (p < 0.05). The expression of M-CSF and VEGFA was higher in the cell lines that strongly induced PD-L1+MDSCs. Peripheral blood from HCC patients had significantly higher percentages of PD-L1+MDSCs in comparison to those of healthy subjects, and the percentages of PD-L1+MDSCs were reduced by HCC treatment, suggesting that we might use PD-L1+MDSCs as a new biomarker of HCC.

Abstract. Accumulating evidence demonstrated that Hox antisense intergenic RNA (HOTAIR) serves essential roles in the development and metastasis of several types of cancer. In hepatocellular carcinoma (HCC), high expression of HOTAIR is associated with poor prognosis, and HOTAIR regulates cell migration and proliferation. However, the downstream molecular targets of HOTAIR depend on the cancer cell types, and little is known about the precise molecular mechanisms of HOTAIR involved in cancer development. The present study investigated the role of HOTAIR in HCC cell lines. Notably, the overexpression of HOTAIR in HCC cell lines did not affect cell migration and proliferation capability. In the microarray analysis, C-C motif chemokine ligand (CCL)2 was identified to be differentially expressed in HOTAIR-overexpressing cells, and it was confirmed that HOTAIR promotes the secretion of CCL2. Furthermore, it was revealed that the proportion of macrophages and myeloid-derived suppressor cells (MDSCs) were increased when peripheral blood mononuclear cells were co-cultured with HOTAIR-overexpressing cells. Collectively, these data suggest that HOTAIR regulates CCL2 expression, which may be involved in the recruitment of macrophages and MDSCs to the tumor microenvironment. IntroductionHox antisense intergenic RNA (HOTAIR), a lncRNA that acts as an oncogenic molecule in various types of cancer, is localized to the HOXC gene cluster. HOTAIR interacts with PRC2 (polycomb repressive complex 2) to enhance H3K27 trimethylation, and thereby decreases the expression of a large number of genes. Several groups, including our laboratory, have reported that high HOTAIR expression is correlated with a poor prognosis in several types of cancer, including breast (1), colorectal (2), non-small lung cell (3), and gastric cancer (4). Interestingly, recent report suggested that effects of HOTAIR are strongly tissue-dependent and can even differ within the same type of cancer (5). Thus, the underlying mechanism by which HOTAIR is involved in malignant progression remains uncertain.Hepatocellular carcinoma (HCC) is the fifth leading cause of cancer and second leading cause of cancer-related mortality worldwide. More than 600,000 deaths are associated with HCC every year worldwide (6). Previous report suggested that the expression of HOTAIR is associated with tumor recurrence and poor prognosis in hepatocellular carcinoma (7,8). Several in vitro analyses were reported using HCC cell line, HepG2; HOTAIR is a FOXC1-activated driver of malignancy, which acts in part through the repression of miR-1 in HepG2 cells (9). HOTAIR silence activates P16 Ink4a and P14 ARF signaling by enhancing miR-218 expression and suppressing Bmi-1 expression, resulting in the suppression of tumorigenesis in HepG2 cells (10). Introduction of human HOTAIR into HepG2 cells revealed that HOTAIR promoted more rapid proliferation (7). Although different intracellular signaling are expected among multiple HCC cell lines, the research of HOTAIR using HCC cell lines except for...

Hepatitis B virus (HBV) reactivation from resolved infection is a serious problem which can frequently lead to severe hepatitis. Generally, it occurs several months after the start of immunosuppressive therapy; however, it sometimes occurs a few years later, even after cessation of therapy. Here we report a patient with de novo HBV infection who had received corticosteroid therapy for pemphigus vulgaris for 6 years. Full-genome HBV sequence analysis using serial serum samples revealed that the patient was infected with HBV subgenotype C2, which had the G1896R mixed mutation in the precore region. Interestingly, it had the immune escape mutations P120A and G145R in the S gene. Because both hepatitis B surface antigen and antibodies to hepatitis B surface antigen (HBsAb) were positive at the onset of the de novo infection, it was considered that HBV with these mutations escaped from neutralization by the pre-existing HBsAbs. This case indicates that HBV reactivation with an immune escape mutant can occur long after immunosuppressive therapy.

In addition to stellate cells and immune cells, inflamed hepatocytes and hepatoma cells express various kinds of chemokines that attract various kinds of immune cells. Previously, we reported that hepatitis B virus (HBV

It has been reported that acute hepatitis B (AHB) patients with genotype A HBV (HBV/A) have been increasing since the 1990s in metropolitan areas in Japan. However, little is known about the trends of HBV genotypes in AHB patients in northeast Japan where genotype B HBV (HBV/B) prevails more than in other areas. In this study, we aimed to clarify the changes in the HBV genotypes and clinical characteristics of AHB patients in this area. HBV genotypes were determined by direct sequencing (n = 125) or enzyme immunoassay (n = 9) using serum samples from AHB patients including fulminant hepatitis in 1987-2014. Among 134 patients, 26 (19%), 33 (25%), and 75 (56%) patients were infected with HBV of genotypes A, B, and C, respectively. HBV/A emerged from 2001 and the percentage was increased gradually up to 48% in 2010-2014, whereas HBV/B was reduced from 40% in 1987-1994 to 10% in 2010-2014. Phylogenetic analysis showed that three major subgenotype A2 strains had come into this area serially. The levels of HBV DNA and prothrombin time were higher in HBV/A patients than other genotypes. This study could not show significant difference in the HBsAg-positive period among genotypes nor the effect of nucleoside analogues to shorten the HBsAg-positive period. A higher level of initial HBV DNA was associated with late disappearance of HBsAg. In conclusion, the percentage of HBV/A in AHB patients has been increasing in northeast Japan since 2001, which is later than metropolitan areas, whereas that of HBV/B is decreasing.