A case of steatohepatitis that developed after pancreaticoduodenectomy and progressed rapidly to liver cirrhosis and hepatocellular carcinoma.

Steatohepatitis has been reported to occur after pancreaticoduodenectomy (PD). We report a case of steatohepatitis that arose after PD and led to decompensated liver cirrhosis and hepatocellular carcinoma (HCC). A 65-year-old man underwent PD for suspected intraductal papillary mucinous neoplasm. Eight years after PD, he was diagnosed with liver cirrhosis by laboratory tests and computed tomography. Histological examination of liver biopsy revealed hepatic steatosis, inflammation with ballooning of hepatocytes, and fibrosis, indicating nonalcoholic steatohepatitis as the cause of liver cirrhosis. Ten years after PD, he developed HCC and radiotherapy was performed because of impaired liver function. Intrahepatic metastasis appeared subsequently, but no further treatment could be performed due to decompensated liver cirrhosis. Survival time after PD is being prolonged by improvements in imaging studies and therapeutic strategies. Accordingly, we consider that progression to liver cirrhosis and HCC will occur increasingly in cases such as the present patient, which will become a severe problem in long-term post-PD survival. Therefore, it is necessary to clarify the precise mechanism of steatohepatitis after PD and establish appropriate therapeutic strategies.

Hepatocellular Carcinoma Pseudoprogression Involving the Main Portal Vein, Right Ventricular Invasion, and Exacerbation of Lung Metastases in a Patient on Atezolizumab Plus Bevacizumab.

A 70-year-old man was diagnosed with hepatocellular carcinoma (HCC) with portal vein invasion and lung metastases, for which atezolizumab plus bevacizumab (ATZ/BEV) was initiated. After two months, computed tomography revealed tumor growth accompanied by ascites, right ventricular invasion, exacerbation of the lung metastases, and main portal vein invasion. However, continuation of ATZ/BEV caused remarkable size reductions in all lesions, finally resulting in the disappearance of the vascular invasion and lung metastases after nine cycles of treatment. The tumor growth was considered to reflect pseudoprogression, which is difficult to distinguish from hyperprogression. We herein report a remarkable HCC case of pseudoprogression on ATZ/BEV.

Expression Pattern of Plexin Domain Containing 2 in Human Hepatocellular Carcinoma.

Plexin domain containing 2 (PLXDC2) is expressed in endothelial cells of tumor stroma, neural progenitor cells, and pluripotent stem cells, but their respective tissue expression pattern is not fully understood. In this study, we investigated the expression pattern of PLXDC2 in human hepatocellular carcinoma (HCC) tissues using a highly specific anti-PLXDC2 rabbit monoclonal antibody, which was recently developed. PLXDC2 was expressed in human HCC tissues including HCC cells, tumor vascular endothelial cells, and some infiltrating cells. The developed anti-PLXDC2 antibody allowed for highly specific and low background staining. Based on these current findings of PLXDC2 expression in human HCC tissues, the window may now be open to explore the role of PLXDC2 in human HCC.

A substitution in the pre-S1 promoter region is associated with the viral regulation of hepatitis B virus.

BACKGROUND: Much evidence has demonstrated the influence of Hepatitis B virus (HBV) mutations on the clinical course of HBV infection. As large (L) protein plays a crucial role for viral entry, we hypothesized that mutations in the pre-S1 promoter region might affect the expression of L protein and subsequently change the biological characters of virus. METHODS: Patients infected with genotype C HBV were enrolled for analysis. HBV DNA sequences were inserted into a TA cloning vector and analyzed. To evaluate the effects of mutations in the pre-S1 promoter region, promoter activity and the expression of mRNA and L protein were analyzed using HepG2 cells. RESULTS: In total, 35 patients were enrolled and 13 patients (37.1%) had a single base substitution in the pre-S1 promoter region; the most frequent substitution was a G-to-A substitution at the 2765th base (G2765A) in the Sp1 region. The HBV viral load showed a negative correlation with the substitution ratio of the Sp1 region or G2765A (r = - 0.493 and - 0.473, respectively). Among those with a viral load ≤5.0 log IU/ml, patients with the G2765A substitution showed a significantly lower HBV viral load than those with the wild-type sequence. HepG2 cells transfected with the G2765A substitution vector showed reduced luciferase activity of the pre-S1 promoter, as well as reduced expression of pre-S1 mRNA and L protein. Furthermore, the G2765A substitution greatly reduced the L protein expression level of vector-produced virus particles. CONCLUSION: G2765A substitution in the pre-S1 promoter reduced the expression of L protein and resulted in a low viral load and less severe disease in chronic HBV infections.

Changing clinical and molecular characteristics of hepatitis E virus infection in Mie Prefecture, Japan: Disappearance of indigenous subtype 3e strains.

AIM: To evaluate the clinical and molecular characteristics of hepatitis E virus (HEV) infection in Mie Prefecture, Japan, from 2004 through 2018. METHODS: The clinical information of hepatitis E cases was collected from 21 medical institutions in Mie Prefecture. The nucleotide sequences of infecting HEV strains were determined for cases with available serum samples. The origins or transmission routes were inferred from phylogenetic analyses of the nucleotide sequences. RESULTS: Fifty-three patients were diagnosed with HEV infection. The number of cases increased each year through 2012 and then decreased. Analyses of the clinical characteristics of the cases indicated that even mild cases were detected in the latter 10 years of the study. Nucleotide sequence analyses were undertaken on 38 of the 53 cases. The HEV subtype 3e (HEV-3e) strains identified for 13 cases were closely related to a swine HEV-3e strain that was isolated from the liver of a pig bred in Mie Prefecture. The number of cases infected with the indigenous Mie HEV-3e strains increased until 2012 but have not been reported since 2014. In the latter half of the study, cases involving various HEV strains of different genotypes and subtypes emerged. CONCLUSIONS: The disappearance of indigenous Mie HEV-3e strains appeared to be the primary cause for the decrease in hepatitis E cases in Mie Prefecture. The disappearance might have been associated with improved hygienic conditions on pig farms or the closure of contaminated farms. The results suggest that indigenous HEV strains can be eradicated by appropriate management.

Ratio between estimated glomerular filtration rates of creatinine and cystatin C predicts overall survival in patients with hepatocellular carcinoma.

AIM: Hepatocellular carcinoma (HCC) patients with sarcopenia have a poor survival, but there are no predictive markers for survival relating to muscle mass and liver function. Therefore, we investigated whether the ratio between estimated glomerular filtration rates of serum creatinine (Scre) and serum cystatin C (Scys) (eGFRcre/eGFRcys) can be used as a predictive marker of survival in HCC patients. METHODS: First, the correlation between Scre/Scys ratio and muscle mass was examined in 50 patients with chronic liver disease. Second, a change in Scre/Scys ratio relating to liver function was investigated in cirrhotic rats. Finally, the relationship between the eGFRcre/eGFRcys ratio and survival was assessed in 86 HCC patients. RESULTS: The Scre/Scys ratio was correlated with skeletal muscle mass index (r = 0.331, P = 0.019) and psoas muscle area index (r = 0.397, P = 0.004) in chronic liver disease patients. In cirrhotic rats, Scre and Scre/Scys ratio were decreased corresponding with liver function. Thirty-five of 86 HCC patients died within the average follow-up period of 35 months. The patients with an eGFRcre/eGFRcys ratio <1.26 had significantly longer rates of survival compared to patients with an eGFRcre/eGFRcys ratio ≥1.26 (28.8 vs. 18.5 months, P = 0.001). Using multivariate Cox regression analyses, the patient-related eGFRcre/eGFRcys ratio (hazard ratio [HR], 4.178; P = 0.007), as well as the tumor-related factors α-fetoprotein (HR, 1.000; P < 0.001) and Barcelona Clinic Liver Cancer stage (HR, 2.589; P < 0.001), were independent predictors of survival. CONCLUSION: The Scre/Scys ratio is associated with muscle mass and liver function. Furthermore, the eGFRcre/eGFRcys ratio could serve as a useful predictive marker for survival of HCC.

Changes in liver function and body composition by direct-acting antiviral therapy for hepatitis C virus infection.

AIM: Management of low skeletal muscle mass (LSM) is a very important topic as LSM affects patient mortality in liver diseases. Changes in body composition are unexplored in chronic hepatitis C virus (HCV) patients, including those with liver cirrhosis, who receive direct-acting antiviral (DAA) therapy. Body composition measurements and liver function tests were carried out before and after DAA therapy. METHODS: Blood examination, visceral fat area (VFA) and extremity skeletal muscle mass were measured using the multifrequency bioelectrical impedance analysis method: (i) at 24 weeks before DAA therapy; (ii) at the start of DAA therapy; (iii) at the end of DAA therapy; (iv) at 24 weeks after DAA therapy; and (v) at 48 weeks after DAA therapy. RESULTS: Serum albumin (Alb) levels were significantly increased at 48 weeks post DAA therapy, especially in patients with LSM. Skeletal muscle mass index (SMI) was significantly increased after DAA therapy (at 24 weeks and 48 weeks post DAA therapy) in patients with LSM (P < 0.05). An increase in SMI was associated with an increase in body weight or a decrease in VFA. CONCLUSIONS: We continuously measured body composition in HCV-infected patients who received DAA therapy and found that skeletal muscle mass was significantly increased, associated with an elevation of serum Alb levels and/or body weight or reduction in VFA, but only in patients who presented with LSM before DAA therapy.

Epigenetic regulation of proliferation and invasion in hepatocellular carcinoma cells by CBP/p300 histone acetyltransferase activity.

Altered epigenetic control of gene expression plays a substantial role in tumor development and progression. Accumulating studies suggest that somatic mutations of CREB binding proteins (CBP)/p300 occur in some cancer cells. CBP/p300 possess histone acetyltransferase (HAT) activity, and are involved in many cellular processes. In this study, we investigated the expression and functional role of CBP/p300 in hepatocellular carcinoma (HCC) using the specific inhibitor C646 of CBP/p300 HAT activity. We examined its effect on several apoptosis-related proteins and invasion-related genes. The results showed that CBP/p300 were highly expressed in HCC tissues and that expression of p300, but not of CBP, was strongly correlated with the malignant character of HCC. C646 inhibited proliferation of HCC cell lines in a dose dependent manner. C646 significantly augmented TRAIL-induced apoptotic sensitivity, which was accompanied by reduced levels of survivin, in HepG2, HLE and SK-HEP1 cells. C646 significantly inhibited invasion of Huh7, HLE and SK-HEP1 cells. The level of matrix metallopeptidase 15 (MMP15) mRNA expression was significantly reduced, whereas the level of laminin alpha 3 (LAMA3) and secreted phosphoprotein 1 (SPP1) mRNA expression was significantly increased in Huh7 cells following exposure to C646. In conclusion, our results suggest that CBP/p300 HAT activity has an important role in malignant transformation, proliferation, apoptotic sensitivity and invasion in HCC. CBP/p300 could be a promising therapeutic target in HCC.

Corrigendum: Human ß-defensin-3 inhibits migration of colon cancer cells via downregulation of metastasis-associated 1 family, member 2 expression.

In this article, Fig. 2 is incorrect. The corrected Fig. 2 is shown using data from the tissue array samples. The new figure demonstrates the same findings as the original figure. Accordingly, in the paragraph of Materials and methods, the sentence '...surgically resected colon cancer tissues' and 'This study was...research committee' and in the paragraph of Results, the sentence 'Similar results were...tissue array samples' should be deleted. The above changes do not alter the original conclusions of this study. [the original article was published in the International Journal of Oncology 45: 1059-1064, 2014 DOI: 10.3892/ijo.2014.2507].

Pulmonary tuberculoma in a patient with chronic hepatitis C: a clinical pitfall in the treatment strategy.

We herein report a clinical pitfall regarding the treatment of a case of pulmonary tuberculoma in a patient with chronic hepatitis C. The patient presented with both chronic hepatitis C and pulmonary tuberculoma, and we initiated treatment of the chronic hepatitis C first due to the potential for liver injury; however, the patient's condition worsened in terms of the pulmonary tuberculosis. This case highlights the need to select the initial treatment for pulmonary tuberculoma, not chronic hepatitis C. In addition, we report that, although the administration of anti-tuberculosis chemotherapy regimens containing pyrazinamide (PZA) substantially increases the incidence of drug-induced hepatitis in patients with chronic hepatitis, we were fortunately able to use PZA without observing drug-induced hepatitis in this case because we closely monitored the patient's liver function.

Human ß-defensin-3 inhibits migration of colon cancer cells via downregulation of metastasis-associated 1 family, member 2 expression.

The innate immune system plays an important role as the first line of defense against many types of microbes. Accumulating reports suggest that human ß-defensins (hBDs) are expressed by and have certain roles in some cancer cells. In this study, we investigated the roles of hBD-3 in colon cancer cells. The expression of hBD-3 was examined by reverse transcriptase-polymerase chain reaction analysis of colon cancer cell lines and immunohistochemical staining of colon cancer tissues. The effect of hBD-3 on proliferation of colon cancer was assessed using the MTT assay and a real-time cell analyzer, and the effect of hBD-3 on the migration of colon cancer cells was also examined. The results showed that hBD-3 is not expressed in colon cancer cells but is produced by tumor-infiltrating monocytes. Migration of colon cancer cells was significantly inhibited by hBD-3 in a dose-dependent manner, although proliferation of colon cancer cells was not affected by administration of hBD-3. Moreover, reduced expression of metastasis-associated 1 family, member 2 (MTA2) mRNA in colon cancer cells was associated with exposure to hBD-3. In conclusion, progression of colon cancer was inhibited by hBD-3 in a paracrine fashion. Therefore, hBD-3 may be a potent new agent for treating colon cancer.

Resveratrol sensitizes HepG2 cells to TRAIL-induced apoptosis.

Resveratrol is a natural polyphenol found in a wide variety of plants, including grapes, berries, and peanuts. Resveratrol can modulate a wide spectrum of molecular targets, including those involved in cancer signaling pathways. Here, we evaluated the role of resveratrol in tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) and examined the molecular mechanisms in the human hepatocellular carcinoma cell line HepG2. We used the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay to assess cell viability, flow cytometry to analyze cell cycle and apoptosis, and immunoblotting to detect protein expression. Resveratrol decreased cell viability at a concentration of 100 µmol/l or higher. At a concentration of 50 µmol/l, resveratrol induced S phase arrest of the cell cycle without apoptosis. In addition, phospho-AMPK increased significantly in a dose-dependent manner. Resveratrol was found to synergistically augment TRAIL-induced apoptosis. The rates of early apoptosis were 3.4, 9.6, and 49.6% on treatment with 50 µmol/l resveratrol, 10 ng/ml TRAIL, and both reagents, respectively. Resveratrol significantly downregulated the expression of survivin in a dose-dependent manner. In conclusion, we found that that resveratrol could augment TRAIL sensitivity by downregulating survivin. These results suggest that combination resveratrol with TRAIL may be an effective new strategy for the treatment of hepatocellular carcinoma.

The long-term effects of splenectomy and subsequent interferon therapy in patients with HCV-related liver cirrhosis.

Partial splenic embolization (PSE) or splenectomy is widely performed to increase platelet counts for interferon (IFN) therapy. The aim of the present study was to evaluate the long-term effects of splenectomy and subsequent IFN therapy in patients with hepatitis C virus (HCV)-related liver cirrhosis (LC). The present study included 19 patients with HCV-related LC who underwent splenectomy for thrombo-cytopenia caused by hypersplenism. IFN therapy was performed in all 19 patients. The effects of splenectomy and subsequent IFN therapy on peripheral blood counts, liver function, carcinogenesis and survival rates were evaluated. Splenectomy was safely performed in all patients without major complications with the exception of portal thrombosis, which, however, it did not affect liver function when treated appropriately. Thrombocytopenia improved and IFN therapy could be performed in all the patients. A sustained virological response (SVR) was not observed in patients with genotype 1 although it was observed in 75% of patients with genotype 2. Due to severe side effects, five patients did not undergo scheduled IFN therapy. Over 5 years, the mean platelet number increased from 5.2 x 10(4) to 16.8 x 10(4)/mm3 (P<0.01) and liver function improved following splenectomy (albumin, Alb: 3.5­3.8 g/dl; total bilirubin, T-Bil: 1.0­0.7 mg/dl; prothrombin time, PT: 74.1­97.7%; total cholesterol; T-cho: 140­168 mg/dl; P<0.05). Hepatocellular carcinoma (HCC) occurred in only one patient during long­term observation and follow­up of the patients not presenting with HCC at entry. The results of the present study demonstrate that splenectomy followed by interferon therapy could be beneficial in patients with HCV-related LC.

Magnetic resonance laparoscopy: A new non-invasive technique for the assessment of chronic viral liver disease.

AIM: Laparoscopy-guided liver biopsy is the most accurate method for assessing liver fibrosis but have several limitations. We designed a non-invasive method, called magnetic resonance laparoscopy (MRL), based on gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid-enhanced magnetic resonance imaging, to assess liver fibrosis in patients with chronic hepatitis B and C virus. METHODS: We prospectively analyzed 49 patients with normal liver and 353 patients with chronic viral hepatitis, laparoscopic liver biopsy was performed on 109 patients and 244 patients were diagnosed as having liver cirrhosis clinically. The MRL findings of the liver surface were classified into three categories: (i) smooth (essentially smooth surface of the entire liver or with limited areas of depression); (ii) partially irregular (several interconnected depressions on the surface mainly in the left lobe of the liver); and (iii) diffusely irregular (nodules present on the liver surface). Patients with diffusely irregular liver surface was diagnosed as liver cirrhosis. RESULTS: The liver surface changed with the progression of liver fibrosis from smooth, partially irregular to diffusely irregular, irrespective of viral type. The sensitivity, specificity, positive and negative predictive values for the diagnosis of cirrhosis according to the surface findings on MRL were 96%, 100%, 95% and 95%, respectively. The cirrhotic liver showed: (i) disappearance of impression of the right ribs; (ii) enlargement of the lateral segment; and (iii) atrophy of the right lobe according to Child-Pugh classification. CONCLUSION: Our data indicated that MRL is a potentially useful non-invasive examination for evaluation of liver fibrosis associated with viral hepatitis.

The expression and function of Toll-like receptors 3 and 9 in human colon carcinoma.

Toll-like receptors (TLRs) are pattern-recognition receptors that are important in immune signaling. TLR recognition of various viral components including double-stranded RNA (TLR3) and unmethylated CpG-DNA (TLR9) plays a crucial role in cell survival. However, TLR expression and function in colon carcinoma cells are not well clarified. We investigated the expression of TLR3 and TLR9 in colon carcinoma cells using immunohistochemical methods. The function of TLR3 and TLR9 signaling in carcinoma cell lines was studied by direct cell stimulation with, or by cell transfection of, polyinosinic-polycytidylic acid (Poly I:C), a synthetic form of dsRNA, and by cell stimulation with CpG-oligodeoxynucleotides (ODNs), respectively. Positive TLR3 and TLR9 immunohistochemical staining was observed in 91 and 86% of human hepatocellular carcinoma (HCC) tissues, respectively. Cell surface stimulation of TLR3 with Poly I:C did not affect cell viability but it did activate NF-κB activity. By contrast, stimulation of intracellular TLRs with transfected Poly I:C significantly induced apoptosis. Cell surface stimulation of TLR9 with CpG-ODNs promoted cell proliferation, and, furthermore, these CpG-ODN TLR9 agonists reduced the cytotoxicity of the anticancer drug adriamycin. Cell surface expression of TLR3 and TLR9 in colon carcinoma cells plays an important role in cell survival. In addition, the proapoptotic activity of intracellularly expressed TLR3 may provide the possibility of using TLR3 agonists as novel clinical cytotoxic agents against colon carcinoma cells.

Des-γ-carboxy prothrombin ratio measured by P-11 and P-16 antibodies is a novel biomarker for hepatocellular carcinoma.

Serum tumor markers, including α-fetoprotein (AFP) and des-γ-carboxy prothrombin (DCP), are currently used in the diagnosis of hepatocellular carcinoma (HCC). There is, however, an aberrant increase in serum DCP in patients with obstructive jaundice, vitamin K deficiency or who are taking warfarin, resulting from a problem with the current methodology for measurement of this marker. This study aimed to elucidate the utility of a new biomarker, NX-PVKA, for early diagnosis of HCC. A total of 96 patients were included in the HCC group. The control group included 138 liver cirrhosis (LC) patients without HCC. Serum concentrations of conventional DCP, AFP, AFP-L3 and NX-PVKA were measured. The NX-PVKA ratio was calculated by dividing DCP by NX-PVKA. In patients not taking warfarin, the area under the curve values of DCP, NX-PVKA ratio, AFP and AFP-L3 were 0.715, 0.690, 0.737 and 0.654, respectively, confirming the clinical utility of these markers in detecting HCC. In cases with DCP > 35 mAU/mL in particular, a significant increase in the NX-PVKA ratio was observed in patients with HCC. In those cases, the cut-off value for the NX-PVKA ratio that was optimized by the receiver operating characteristic (ROC) curve was 1.15. In addition, the sensitivity and specificity for diagnosing HCC were 69.2% and 75.9%, respectively. Patients with HCC had higher NX-PVKA ratios compared to patients with LC taking warfarin (P = 0.063). These results suggest that, when used in combination with DCP, the NX-PVKA ratio is a promising novel marker for the detection of HCC.

Sorafenib and TRAIL have synergistic effect on hepatocellular carcinoma.

A multi-kinase inhibitor, sorafenib, was recently approved and is currently recommended for the treatment of advanced hepatocellular carcinoma (HCC). However, HCC treatment outcomes are still poor and necessitate improvement. Therefore, we investigated the influence of sorafenib in combination with each of cytotoxic chemotherapy agents, hypoxia or tumor necrosis factor (TNF)-related apoptosis­inducing ligand (TRAIL), on cytotoxicity to determine which is the better adjuvant. Additive cytotoxicity of sorafenib to chemotherapy agents, hypoxia and TRAIL, to HCC cells was assessed using cell viability assay. Intracellular levels of anti-apoptotic proteins were determined using western blot analysis. Activation of Wnt/ß-catenin signaling was assessed using a luciferase reporter gene assay. Sorafenib significantly and synergistically enhanced the cytotoxicity of TRAIL to HCC cells and 4',6-diamidino-2-phenylindole (DAPI) staining showed increased apoptosis among cells treated with sorafenib and TRAIL. This augmentation in cytotoxicity was derived from sorafenib-mediated downregulation of anti-apoptotic proteins. However, sorafenib did not enhance the cytotoxicity of chemotherapy agents (cisplatin, 5-FU or doxorubicin) or hypoxic treatment to HCC. Moreover, hypoxic treatment induced Wnt/ß-catenin signaling activation. Our data showed that in combination TRAIL and sorafenib had a synergistic cytokilling effect on HCC cells and that this effect derived from sorafenib-mediated downregulation of anti-apoptotic proteins.

Clinical utility of transarterial infusion chemotherapy using cisplatin-lipiodol emulsion for unresectable hepatocellular carcinoma.

BACKGROUND: We evaluated the clinical efficacy of transarterial infusion chemotherapy using a cisplatin-lipiodol emulsion for unresectable hepatocellular carcinoma (HCC). PATIENTS AND METHODS: Fifty-seven patients with advanced HCC, with no indications for surgical resection or local ablative therapy, such as percutaneous ethanol injection and radiofrequency ablation, were enrolled in this retrospective study. RESULTS: Twelve patients were treated with cisplatin-alone at a dose of 65 mg/m(2) by infusion into the artery. Forty-two patients were treated with the same dose of cisplatin suspended in 1-10 ml of lipiodol (C/LPD). Cumulative survival rates in the cisplatin-treated group were 46.2% at one year, and 18.5% at two years, whereas these in the C/LPD group were 81.6% and 44.4%, respectively, with a significant difference between the two groups (p<0.01). In the cisplatin-treated group (n=13), no (0%) patients had a complete response (CR), two (15%) a partial response (PR), three (23%) no change (NC), and eight (62%) progressive disease (PD). In the C/LPD group (n=44), four (9%) patients had CR, 16 (35%) PR, 12 (26%) NC, and 12 (26%) PD. CR and PR were seen in 15% of the cisplatin-treated group and in 44% of the C/LPD group. C/LPD was significantly more effective than cisplatin-alone (p=0.039). Some patients showed tumor response to C/LPD after intra-arterial infusion of low-dose 5-fluorouracil. CONCLUSION: C/LPD produced superior effects compared to cisplatin-alone for unresectable HCC, causing no major side-effects, and increasing the survival rate.

Sarcomatous hepatocellular carcinoma with remittent fever.

We herein report a rare case of hepatocellular carcinoma (HCC) with sarcomatous changes. A 66-year-old man was admitted to our hospital with a high fever and upper abdominal pain. Initially, he was diagnosed as having a liver abscess; however, antibiotic treatment and drainage were ineffective. Further imaging studies revealed the typical appearance of HCC: the tumor had invaded the hepatic and portal veins. Surgical resection of the tumor was performed. A pathological examination demonstrated the presence of a sarcomatous hepatocellular carcinoma. Sarcomatous hepatocellular carcinoma with remittent fever is a rare disease entity.

UV irradiation of immunized mice induces type 1 regulatory T cells that suppress tumor antigen specific cytotoxic T lymphocyte responses.

We previously showed that exposure to UV radiation after immunization suppresses Th1 and Th2 immune responses, leading to impaired Ab and allo-immune responses, but the impact of UV radiation after immunization on anti-tumor immune responses mediated by tumor-specific CD8(+) T cell responses remains less clear. Furthermore, the exact phenotypic and functional characteristics of regulatory T cell population responsible for the UV-induced immunosuppression still remain elusive. Using the MBL-2 lymphoma cell line engineered to express OVA as a surrogate tumor Ag, here we demonstrate that UV irradiation after tumor Ag-immunization suppresses the anti-tumor immune response in a manner dependent on the immunizing Ag. This suppression was mediated by interleukin (IL)-10 released from CD4(+) CD25(+) T cells, by which impaired the induction of cytotoxic T lymphocytes (CTL) able to kill Ag-expressing tumor cells. In addition, we generated a panel of T cell clones from UV-irradiated and non-irradiated mice, and all of the clones derived from UV-irradiated mice had a Tr1-type regulatory T cell phenotype with expression of IL-10 and c-Maf, but not Foxp3. These Tr1-type regulatory T cell clones suppressed tumor rejection in vivo as well as Th cell activation in vitro in an IL-10 dependent manner. Given that suppression of Ag-specific CTL responses can be induced in Ag-sensitized mice by UV irradiation, our results may imply that exposure to UV radiation during premalignant stage induces tumor-Ag specific Tr1 cells that mediate tumor-Ag specific immune suppression resulting in the promotion of tumor progression.