Risk Factors for Immune Checkpoint Inhibitor-Induced Liver Injury and the Significance of Liver Biopsy.

Immune checkpoint inhibitor (ICI)-induced liver injury (LI) is a common adverse event, but the clinical characteristics based on the classification of hepatocellular injury and cholestatic types are not fully evaluated. This study aims to analyze risk factors and histological findings in relation to the classification of ICI-induced LI. In total, 254 ICI-induced LI patients among 1086 treated with ICIs between September 2014 and March 2022 were classified according to the diagnostic criteria for drug-induced LI (DILI), and their risk factors and outcomes were evaluated. Kaplan-Meier analyses showed that overall survival in patients with hepatocellular-injury-type LI was significantly longer than others (p < 0.05). Regarding pre-treatment factors, the lymphocyte count was significantly higher in patients with ICI-induced LI, especially in hepatocellular-injury-type LI. Gamma glutamyl transferase (γGTP) and alkaline phosphatase (ALP) were also significantly lower in patients with ICI-induced LI (p < 0.05). Multivariate analyses revealed that malignant melanoma, high lymphocyte count, and low ALP levels were extracted as factors contributing to hepatocellular-injury-type LI. The histological findings among 37 patients diagnosed as ICI-induced LI via liver biopsy also revealed that the spotty/focal necrosis was significantly frequent in hepatocellular-injury-type LI, whereas ductular reactions were frequently observed in cholestatic-type LI. It is suggested that the histological inflammation pattern in patients with LI is closely correlated with the type of DILI.

Factors associated with the response to atezolizumab/bevacizumab combination therapy for hepatocellular carcinoma.

Background and Aim: The purpose of this study was to analyze factors associated with the overall survival (OS) of atezolizumab/bevacizumab combination therapy for advanced hepatocellular carcinoma (aHCC). We also assessed the OS of patients with ineffective therapy and those who discontinued treatment owing to adverse events (AEs). Methods: This retrospective multicenter study involved 139 patients with aHCC who received atezolizumab/bevacizumab combination therapy between November 2020 and September 2022. Results: The median duration of treatment was 136.5 days, and the median observation period was 316 days. The overall response rate was 40%, and the disease control rate was 78% according to mRECIST criteria. Grade ≥2 AEs occurred in 63 patients (43%) and led to treatment discontinuation in 16 patients. Multivariate analysis revealed that treatment response and occurrence of grade ≥2 AEs after therapy, as well as low level of albumin-bilirubin (ALBI) grade and low level of des-gamma carboxy prothrombin (DCP) before therapy, were extracted as factors that contributed to OS. Log-rank tests with the Kaplan-Meier method showed significant differences in OS among these factors. The OS of patients who discontinued owing to AEs was significantly shorter than that of other patients. Conclusion: Not only factors before therapy but also treatment response and the appearance of AEs are involved in OS for atezolizumab/bevacizumab combination therapy. Although the development of AEs also contributed to OS, appropriate management of AEs is important to avoid discontinuing treatment with this combination.

Significance of post-progression therapy after tyrosine kinase inhibitors for advanced hepatocellular carcinoma.

Background and Aim: Molecular-targeted therapies such as sorafenib and lenvatinib have long been used as first-line treatment for advanced hepatocellular carcinoma (aHCC). However, adverse events or limited therapeutic effects may necessitate the change to another therapeutic option, known as post-progression therapy. To investigate the significance of post-progression therapy, we analyzed the outcomes of aHCC patients following first-line molecular-targeted therapy in a real-world study. Methods: This retrospective, multicenter study involved patients with aHCC who received sorafenib or lenvatinib as first-line therapy between January 2011 and September 2021. Results: In total, 513 patients were analyzed: 309 treated with sorafenib and 204 with lenvatinib. The overall response and disease control rates were 15 and 50%, respectively, in the sorafenib group and 30 and 75%, respectively, in the lenvatinib group (P < 0.001). Kaplan-Meier analysis revealed no significant differences in progression-free survival and overall survival (OS) between the two treatments. Multivariate analysis revealed that fibrosis-4 index, disease control rate, post-progression therapy, and use of an immune checkpoint inhibitor (ICI) were significantly associated with OS. OS was significantly longer in patients who received post-progression therapy than in those who did not (log-rank P < 0.001). Most patients who received an ICI as post-progression therapy had previously received lenvatinib. Among lenvatinib-treated patients, OS was significantly longer in patients who received an ICI than in patients received another or no post-progression therapy (P = 0.004). Conclusion: The introduction of newer drugs for post-progression therapy is expected to prolong survival. ICI-based regimens appear to be effective after lenvatinib.

Acid-treated high-amylose corn starch suppresses high-fat diet-induced steatosis.

Resistant starch (RS) has been reported to improve steatosis as well as obesity. Type 4 resistant starch (RS4), a chemically modified starch, is particularly hard to digest and suggesting higher efficacy. However, because the effects of RS4 on steatosis are not yet fully understood, the effects of RS4 on steatosis were examined using a murine high-fat diet model. Seven-week-old male mice were divided into three groups and fed a normal diet, a high-fat diet (HFD), or a high-fat diet with added RS (HFD + RS). Amylofiber SH® produced from acid-treated corn starch was used as the dietary RS. At 22 weeks old, hepatic steatosis and short chain fatty acid (SCFA) content and gut microbiota in cecum stool samples were analyzed. The ratio of body weight to 7 weeks was significantly suppressed in the HFD + RS group compared to the HFD group (132.2 ± 1.4% vs. 167.2 ± 3.9%, p = 0.0076). Macroscopic and microscopic steatosis was also suppressed in the HFD + RS group. Analysis of cecum stool samples revealed elevated SCFA levels in the HFD + RS group compared with the HFD group. Metagenome analysis revealed that Bifidobacterium (17.9 ± 1.9% vs. 3.6 ± 0.7%, p = 0.0019) and Lactobacillus (14.8 ± 3.4% vs. 0.72 ± 0.23%, p = 0.0045), which degrade RS to SCFA, were more prevalent in the HFD + RS group than the HFD group. In conclusion, RS4 suppressed steatosis, and increased Bifidobacterium and Lactobacillus, and SCFAs. RS4 may prevent steatosis by modulating the intestinal environment.

Jejunal variceal rupture in a patient with myelofibrosis: a case report.

An 80-year old man with myelofibrosis and chronic renal disease was admitted to our hospital because of severe anemia and gastrointestinal bleeding. Although no bleeding was observed by upper or lower endoscopy, contrast-enhanced computed tomography revealed an enhanced area in the small intestinal wall that was suspected of being the bleeding site, and was confirmed by double-balloon endoscopy. Based on endoscopic findings, it was difficult to differentiate between variceal rupture and collapse of a submucosal tumor. We performed segmental resection of the small intestine to make a definitive diagnosis and achieve reliable hemostasis. The gross findings confirmed a variceal rupture from the small intestine. His gastrointestinal bleeding stopped and his anemia improved following surgery. Although some cases of portal hypertension in association with myelofibrosis have been reported, we are aware of no prior reports of variceal rupture in the small intestine. To our knowledge, this is the first reported case of ectopic jejunal varices in a patient with myelofibrosis.

Beta-catenin-activated hepatocellular adenoma in a male.

Beta-catenin-activated hepatocellular adenoma is potentially malignant and warrants careful follow-up and surgical resection. Here, we report a 48-year-old man in whom a 55 mm single liver tumor was incidentally detected in the S1 segment. Contrast-enhanced computed tomography scans showed no enhancement in the early phase and a slight defection in the late phase. The tumor was enhanced hyperintensity in the hepatobiliary phase on Gd-ethoxybenzyl-diethylenetriaminepentaacetic acid-enhanced magnetic resonance imaging. The histologic features of ultrasound-guided fine-needle aspiration biopsy indicated hepatocellular adenoma, and the tumor was immunohistochemically positive for glutamine synthetase and ß-catenin. Considering the risk of malignant transformation, he underwent laparoscopic-assisted partial liver resection. The resected tumor did not contain any malignant lesions. This case indicates that aspiration needle biopsy and immunohistochemistry were useful for histological diagnosis and treatment decisions based on the molecular definition of hepatocellular adenoma.

Liver abscess caused by Cutibacterium namnetense after transarterial chemoembolization for hepatocellular carcinoma.

A 72-year-old man underwent transarterial chemoembolization (TACE) for solitary hepatocellular carcinoma (HCC) located on the S6 segment. He had a history of anti-viral therapy for hepatitis C virus and was being treated for diabetes mellitus with inadequate control. On day 28 after TACE, he visited our hospital again, with complaints of fever and abdominal pain in the right upper quadrant. Blood examination showed elevated levels of white blood cells and C-reactive protein. Computed tomography showed a poorly marginated, low-density lesion measuring 9.5 × 8.0 × 4.0 cm, forming multiple small gas bubbles, located superiorly, and in contact with HCC treated by TACE. Ultrasound-guided puncture revealed whiffy and muddy pus. Gram staining of the pus showed the presence of numerous gram-positive rods, which were identified as Cutibacterium namnetense. He underwent percutaneous trans-hepatic abscess drainage and received antibiotics treatment. The abscess was successfully treated, and he was discharged on day 19. The incidence of liver abscess after TACE is rare, and intestinal microbiota have been reported to be the common pathogens. To the best of our knowledge, this is the first case of liver abscess caused by Cutibacterium namnetense.

Clinical features of immune-mediated hepatotoxicity induced by immune checkpoint inhibitors in patients with cancers.

PURPOSE: The risk factors and clinical characteristics of ICI-induced immune-mediated hepatotoxicity (IMH) are not fully understood. Thus, the present study sought to clarify the clinical features of IMH. METHODS: All patients treated with ICIs between September 2014 and April 2019 at our institution were included. Clinical data were retrospectively collected from medical records. The frequency of grade ≥ 2 liver damage, clinical characteristics, and risk factors for developing IMH were examined. RESULTS: Overall, 250 patients (median age 71 years; range 30-87 years; 202 males and 48 females) were included in the analyses. Forty-five patients had elevated transaminase levels (> threefold the upper limit of normal). Of these, 21 were considered to have IMH. The remaining 24 patients had other causes of elevated transaminase levels. Steroids were administered to 13/21 patients with IMH. Although all patients exhibited improvement, IMH was not associated with the anticancer efficacy of the ICIs or OS. A multivariable analysis revealed that IMH was significantly associated with malignant melanoma (odds ratio [OR] 11.6; 95% confidence interval [CI] 3.5-38.0; P = 0.0002) and ipilimumab-nivolumab combination therapy (OR 61.2; 95% CI 7.9-1275.3; P < 0.0001). CONCLUSION: Immune-mediated hepatotoxicity occurred in 9.5% of patients treated with ICIs. Appropriate therapeutic interventions are important to avoid affecting the patient's prognosis, and accurate diagnosis of IMH is essential for this purpose. The frequency of IMH varied according to the type of cancer and the drug used, and was significantly higher in patients with malignant melanoma and in patients given ipilimumab-nivolumab combination therapy.

IgG4-related hypophysitis in patients with autoimmune pancreatitis.

PURPOSE: IgG4-related disease involves various organs including the pituitary and pancreas. The prevalence of IgG4-related hypophysitis is relatively rare compared with IgG4-related pancreatitis (autoimmune pancreatitis). Although several cases demonstrating both autoimmune pancreatitis and hypophysitis have been reported, the prevalence of IgG4-related hypophysitis in patients with autoimmune pancreatitis remains unknown. This study aimed at screening for IgG4-related hypophysitis to accurately determine its prevalence in patients with autoimmune pancreatitis. METHODS: In this cohort study, we screened IgG4-related hypophysitis via pituitary magnetic resonance imaging (MRI) and endocrinological examination in 27 patients who were undergoing follow-up for autoimmune pancreatitis at Kobe University Hospital between 2014 and 2018. RESULTS: Among 27 patients with autoimmune pancreatitis, 5 patients exhibited morphological abnormalities in the pituitary (18.5%). Among them, one patient (3.7%) met the criteria for hypophysitis with an enlarged pituitary and stalk concomitant with hypopituitarism. After glucocorticoid treatment, the enlarged pituitary shrank and became empty sella during the clinical course. Four patients (14.8%) revealed empty sella without obvious pituitary dysfunction. Four of 5 patients with morphological pituitary abnormalities showed multiple organ involvement in addition to pancreatic and pituitary involvement. Accordingly, multiple organ involvement was more prevalent in patients with morphological pituitary abnormalities (80%) compared to those without (48%). CONCLUSIONS: Although a large-scale study is necessary to validate these results, these data suggest that the prevalence of hypophysitis in patients with autoimmune pancreatitis may be underestimated. Based on our findings, we recommend screening for hypophysitis, especially in patients with multiple organ involvement.

Effectiveness of endoscopic self-expandable metal stent placement for afferent loop obstruction caused by pancreatic cancer recurrence after pancreaticoduodenectomy.

Afferent loop obstruction caused by cancer recurrence after pancreaticoduodenectomy (PD) can be managed by either surgical or nonsurgical treatment. The general condition of patients with recurrent pancreaticobiliary cancer is often not good enough for them to undergo surgery, so less invasive nonsurgical treatment is desirable. We report a case of a 66-year-old male who had undergone PD for pancreatic head adenocarcinoma 10 months previously and who presented at our hospital with fever and jaundice due to afferent loop obstruction caused by pancreatic cancer recurrence. An endoscopic self-expandable metal stent (SEMS) was placed for afferent loop obstruction without any complications. He quickly recovered after SEMS placement. He retained a good quality of life by receiving chemotherapy until his death due to cancer progression. Our case indicates that this method could be an easy, effective, safe, and less invasive treatment, which may confer a better quality of life for patients with afferent loop obstruction due to cancer recurrence after PD.

Metabolomic analysis to discover candidate therapeutic agents against acute pancreatitis.

Novel and effective drugs against acute pancreatitis are required. Therefore, we examined the changes in the metabolite levels in the serum and pancreatic tissue of mice with cerulein- and arginine-induced pancreatitis using gas-chromatography/mass-spectrometry (GC/MS) and investigated whether these alterations affected the severity of acute pancreatitis. In the cerulein-induced pancreatitis model, 93 and 129 metabolites were detected in the serum and pancreatic tissue, respectively. In the L-arginine-induced acute pancreatitis model, 120 and 133 metabolites were detected in the serum and pancreatic tissue, respectively. Among the metabolites, the concentrations of tricarboxylic acid (TCA) cycle intermediates and amino acids were altered in pancreatitis, and in pancreatic tissue, the levels of the intermediates involved in the initial part of the TCA cycle were increased and those of the intermediates involved in the latter part of the TCA cycle were decreased. Some metabolites exhibited similar changes in both pancreatitis mouse models, e.g., the levels of glutamic acid and O-phosphoethanolamine were significantly decreased in the pancreatic tissue. Supplementation with glutamic acid and O-phosphoethanolamine attenuated the severity of cerulein-induced acute pancreatitis. Our results suggest that GC/MS-based metabolomics is capable of accurately representing the status of acute pancreatitis, leading to the discovery of therapeutic agents for pancreatitis.

Serum fatty acid profiling of colorectal cancer by gas chromatography/mass spectrometry.

AIMS: Several screening methods have been applied for the early diagnosis of colorectal cancer, but most colorectal cancer patients are not diagnosed at a localized stage. In order to find novel biomarkers for the diagnosis of colorectal cancer, profiling of the serum levels of fatty acids, which are the main components of fats and are important factors for human metabolism, was performed using the sera of colorectal cancer patients. MATERIALS & METHODS: A total of 42 colorectal cancer patients and eight healthy volunteers participated in this study. The serum levels of fatty acids, including free fatty acids and esterified fatty acids, were evaluated by gas chromatography/mass spectrometry. Then, partial least squares discriminant analysis was performed on the basis of the serum fatty acids detected by gas chromatography/mass spectrometry. RESULTS: The serum levels of the nine fatty acids exhibited distinct differences between the colorectal cancer patients and healthy volunteers: the levels of four fatty acids were higher in the colorectal cancer patients than the healthy volunteers, and those of the other five fatty acids were lower. These changes were also observed at a very early clinical stage. Furthermore, the levels of very-long-chain fatty acids had a tendency to be increased in the sera of the colorectal cancer patients. CONCLUSIONS: The pathogenesis of colorectal cancer leads to changes in the composition of serum fatty acids including free fatty acids and esterified fatty acids. These results suggest that serum fatty acid profiling may be used as a novel diagnostic tool for early-stage colorectal cancer.

GC/MS-based profiling of amino acids and TCA cycle-related molecules in ulcerative colitis.

OBJECTIVE: The roles that amino acids play in immunity and inflammation are well defined, and the relationship between inflammatory bowel disease (IBD) and certain amino acids has recently attracted attention. In this study, the levels of amino acids and trichloroacetic acid (TCA) cycle-related molecules in the colonic tissues and sera of patients with ulcerative colitis (UC) were profiled by gas chromatography/mass spectrometry (GC/MS), with the aim of evaluating whether the clinical state induced by UC leads to variations in the amino acid profile. MATERIALS AND METHODS: Colonic biopsy samples from 22 UC patients were used, as well as serum samples from UC patients (n = 13), Crohn's disease (CD) patients (n = 21), and healthy volunteers (n = 17). RESULTS: In the GC/MS-based profiling of amino acids and TCA cycle-related molecules, lower levels of 16 amino acids and 5 TCA cycle-related molecules were observed in the colonic lesion tissues of the UC patients, and the serum profiles of amino acids and TCA cycle-related molecules of the UC patients were different from those of the CD patients and healthy volunteers. CONCLUSIONS: Our study raises the possibility that GC/MS-based profiling of amino acids and TCA cycle-related molecules is a useful early diagnostic tool for UC.

A role of the aryl hydrocarbon receptor in attenuation of colitis.

BACKGROUND AND AIMS: The aryl hydrocarbon receptor (AhR), which is a member of the basic helix-loop-helix/Per-Arnt-Sim homology superfamily, plays an important role in multiple biological functions, and AhR knockout (AhR KO) animals suffer from a variety of organ disorders including a decline in the efficacy of their immune system. In addition, AhR activation is known to aid the maintenance of homeostasis in vivo. In this study, we investigated whether AhR is functionally associated with intestinal immunity. METHODS AND RESULTS: In in vivo experiments, it was found that dextran sodium sulfate (DSS)-evoked colitis was more severe in AhR KO mice than in C57BL/6J wild type mice. It was also revealed that the administration of DSS increased the expression levels of AhR and CYP1A1 mRNA in the colon epithelium. In addition, oral administration of ß-naphthoflavone (ßNF), a non-toxic agonist of AhR, suppressed the pathogenesis of DSS-induced colitis. ßNF also attenuated DSS-induced colitis. In cell culture experiments, downregulation of AhR in human colon carcinoma SW480 cells enhanced the inflammatory responses evoked by lipopolysaccharide (LPS), and furthermore, AhR activation attenuated LPS-induced inflammatory responses, suggesting that AhR expressing intestinal epithelial cells are involved in the prevention of colitis. CONCLUSIONS: Our findings about the potential role of AhR activators in epithelial immune regulation aid our understanding of mucosal homeostasis and inflammatory bowl disease (IBD) and suggest that AhR activation has therapeutic value for the treatment of IBD.

GCMS-based metabolomic study in mice with colitis induced by dextran sulfate sodium.

BACKGROUND: Metabolomics provides data about all the metabolic processes of a cell or organism. So far, the changes that occur in the levels of metabolites during the development of colitis have not been fully elucidated. Here we examined the changes of metabolite levels in the serum and colon tissue of colitis mice using gas chromatography mass spectrometry (GC/MS) with the aim of achieving a detailed understanding of the pathogenesis of inflammatory bowel disease (IBD). METHODS: To induce colitis, C57BL/6J mice were administered 3.0% dextran sulfate sodium (DSS) in their drinking water for 5 days and were subsequently given drinking water alone. RESULTS: A total of 77 and 92 metabolites were detected in serum and colon tissue, respectively, and among the metabolites the compositions of TCA cycle intermediates and amino acids changed depending on the degree of colitis. Then, partial least square discriminant analysis (PLS-DA), a multiple classification analysis, showed distinct clustering and clear separation of the groups according to the degree of colitis. Furthermore, PLS-DA loadings plots revealed that succinic acid, indole-3-acetic acid, glutamic acid, and glutamine were the main contributors to the separation of each stage of colitis. In addition, it was revealed that supplementation with glutamine, the level of which was significantly decreased in the acute phase of colonic inflammation, attenuated colitis induced by DSS. CONCLUSIONS: Our results suggest that metabolomics is capable of representing the various degrees of colitis, and our findings will aid in the discovery of therapeutic agents for IBD and other inflammatory disorders by metabolomic approaches.

Gamma interferon produced by antigen-specific CD4+ T cells regulates the mucosal immune responses to Citrobacter rodentium infection.

Citrobacter rodentium, a murine model pathogen for enteropathogenic Escherichia coli, colonizes the surface of intestinal epithelial cells and causes mucosal inflammation. This bacterium is an ideal model for investigating pathogen-host immune interactions in the gut. It is well known that gene transcripts for Th1 cytokines are highly induced in colonic tissue from mice infected with C. rodentium. However, it remains to be seen whether the Th1 or Th2 cytokines produced by antigen-specific CD4(+) T cells provide effective regulation of the host immune defense against C. rodentium infection. To investigate the antigen-specific immune responses, C. rodentium expressing ovalbumin (OVA-C. rodentium), a model antigen, was generated and used to define antigen-specific responses under gamma interferon (IFN-gamma)-deficient or interleukin-4 (IL-4)-deficient conditions in vivo. The activation of antigen-specific CD4(+) T cells and macrophage phagocytosis were evaluated in the presence of IFN-gamma or IL-4 in vitro. IFN-gamma-deficient mice exhibited a loss of body weight and a higher bacterial concentration in feces during OVA-C. rodentium infection than C57BL/6 (wild type) or IL-4-deficient mice. This occurred through the decreased efficiency of macrophage phagocytosis and the activation of antigen-specific CD4(+) T cells. Furthermore, a deficiency in antigen-specific CD4(+) T-cell-expressed IFN-gamma led to a higher susceptibility to mucosal and gut-derived systemic OVA-C. rodentium infection. These results show that the IFN-gamma produced by antigen-specific CD4(+) T cells plays an important role in the defense against C. rodentium.