Gut microbial signatures in clinically stable ulcerative colitis according to the mucosal state and associated symptoms.

BACKGROUND AND AIM: The gut microbiome of patients with clinically stable ulcerative colitis (UC) differs from that of healthy individuals depending on the state of the colonic mucosa, especially with or without advanced scarring; however, the underlying mechanism is unclear. Therefore, this study examined the gut microbiome compositional signatures in patients with significant mucosal scarring and UC-related symptoms. METHODS: Stool samples for gut microbiome analysis were prospectively collected from 57 patients with clinically stable UC between January 1 and December 31, 2022. Data from 57 individuals without inflammatory bowel disease (non-IBD) paired by age and sex were selected from our previous study as the control group. The fecal samples were subjected to 16S rRNA gene sequencing. Associations between gut microbiome profiles and clinical or colonoscopic assessments were examined using diversity and differential abundance analyses. RESULTS: Gut microbiome compositions between the patients with clinically stable UC and non-IBD controls differed significantly. Furthermore, gut microbiome compositions varied between the preserved and altered mucosa groups identified based on mucosal changes in the UC group. Differential abundance test of patients with UC for symptomatic remission based on stool frequency from the two-item patient-reported outcome identified several overlapping taxa specified as gut microbiome signatures, including the Enterobacteriaceae unknown genera (Enterobacteriaceae_g), Klebsiella, and several Lachnospiraceae spp. both in mucosal and symptom change analyses. CONCLUSIONS: The gut microbiome can change with mucosal changes, even in clinically stable UC, and some gut microbial signatures may explain the symptom manifestations in patients with UC showing significant mucosal changes.

SLUG is a key regulator of epithelial-mesenchymal transition in pleomorphic adenoma.

The histogenesis of pleomorphic adenoma (PA) of the salivary glands remains controversial. PAs are characterized by the transition of epithelial cells to spindled mesenchymal cells, known as epithelial-mesenchymal transition (EMT). The present study aimed to identify a major EMT-inducing transcription factor (EMT-TF) in PAs. Real-time PCR analysis of SNAIL, SLUG, ZEB1, and TWIST1 demonstrated that only SLUG was significantly upregulated in normal salivary glands and PAs. Combined in situ hybridization for SLUG and multiplex immunohistochemistry for CK19 and P63 revealed that SLUG was specifically expressed in the myoepithelial cells of normal salivary glands. In PAs, SLUG was expressed in neoplastic myoepithelial cells and stromal cells but not in the luminal cells lining the inner layers of tumor glands. SLUG expression showed no correlation with PLAG1 expression, and in vitro experiments demonstrated that PLAG1 suppression in primary cultured PA cells or PLAG1 overexpression in HEK 293 T cells did not affect SLUG levels, indicating that PLAG1 was not involved in the upregulation of SLUG in PAs. The suppression of SLUG expression in cultured PA cells resulted in a morphology change to a less elongated shape and attenuated tumor growth. In addition, SLUG downregulation led to increased E-cadherin and decreased N-cadherin and vimentin expression levels along with decreased migratory activity in cultured PA cells. These findings suggest that SLUG is a major TF that can induce EMT in PAs. In summary, SLUG is specifically and highly expressed in the myoepithelial cells and stromal cells of PAs and is a key regulator of EMT in PAs.

Metformin Protects the Intestinal Barrier by Activating Goblet Cell Maturation and Epithelial Proliferation in Radiation-Induced Enteropathy.

Radiotherapy or accidental exposure to high-dose radiation can cause severe damage to healthy organs. The gastrointestinal (GI) tract is a radiation-sensitive organ of the body. The intestinal barrier is the first line of defense in the GI tract, and consists of mucus secreted by goblet cells and a monolayer of epithelium. Intestinal stem cells (ISCs) help in barrier maintenance and intestinal function after injury by regulating efficient regeneration of the epithelium. The Wnt/ß-catenin pathway plays a critical role in maintaining the intestinal epithelium and regulates ISC self-renewal. Metformin is the most widely used antidiabetic drug in clinical practice, and its anti-inflammatory, antioxidative, and antiapoptotic effects have also been widely studied. In this study, we investigated whether metformin alleviated radiation-induced enteropathy by focusing on its role in protecting the epithelial barrier. We found that metformin alleviated radiation-induced enteropathy, with increased villi length and crypt numbers, and restored the intestinal barrier function in the irradiated intestine. In a radiation-induced enteropathy mouse model, metformin treatment increased tight-junction expression in the epithelium and inhibited bacterial translocation to mesenteric lymph nodes. Metformin increased the number of ISCs from radiation toxicity and enhanced epithelial repair by activating Wnt/ß-catenin signaling. These data suggested that metformin may be a potential therapeutic agent for radiation-induced enteropathy.

Combined Administration of Pravastatin and Metformin Attenuates Acute Radiation-Induced Intestinal Injury in Mouse and Minipig Models.

Radiation-induced gastrointestinal (GI) damage is one of the critical factors that serve as basis for the lethality of nuclear accidents or terrorism. Further, there are no Food and Drug Administration-approved agents available to mitigate radiation-induced intestinal injury. Although pravastatin (PS) has been shown to exhibit anti-inflammatory and epithelial reconstructive effects following radiation exposure using mouse and minipig models, the treatment failed to improve the survival rate of high-dose irradiated intestinal injury. Moreover, we previously found that metformin (MF), a common drug used for treating type 2 diabetes mellitus, has a mitigating effect on radiation-induced enteropathy by promoting stem cell properties. In this study, we investigated whether the combined administration of PS and MF could achieve therapeutic effects on acute radiation-induced intestinal injury in mouse and minipig models. We found that the combined treatment markedly increased the survival rate and attenuated histological damage in a radiation-induced intestinal injury mouse model, in addition to epithelial barrier recovery, anti-inflammatory effects, and improved epithelial proliferation with stem cell properties. Furthermore, in minipig models, combined treatment with PS and MF ameliorates gross pathological damage in abdominal organs and attenuated radiation-induced intestinal histological damage. Therefore, the combination of PS and MF effectively alleviated radiation-induced intestinal injury in the mouse and minipig models. We believe that the combined use of PS and MF is a promising therapeutic approach for treating radiation-induced intestinal injury.

Zileuton Alleviates Radiation-Induced Cutaneous Ulcers via Inhibition of Senescence-Associated Secretory Phenotype in Rodents.

Radiation-induced cutaneous ulcers are a challenging medical problem for patients receiving radiation therapy. The inhibition of cell senescence has been suggested as a prospective strategy to prevent radiation ulcers. However, there is no effective treatment for senescent cells in radiation ulcers. In this study, we investigated whether zileuton alleviated radiation-induced cutaneous ulcer by focusing on cell senescence. We demonstrate increased cell senescence and senescence-associated secretory phenotype (SASP) in irradiated dermal fibroblasts and skin tissue. The SASP secreted from senescent cells induces senescence in adjacent cells. In addition, 5-lipoxygenase (5-LO) expression increased in irradiated dermal fibroblasts and skin tissue, and SASP and cell senescence were regulated by 5-LO through p38 phosphorylation. Finally, the inhibition of 5-LO following treatment with zileuton inhibited SASP and mitigated radiation ulcers in animal models. Our results demonstrate that inhibition of SASP from senescent cells by zileuton can effectively mitigate radiation-induced cutaneous ulcers, indicating that inhibition of 5-LO might be a viable strategy for patients with this condition.

Clinical usefulness of noninvasive fibrosis indices for predicting hepatocellular carcinoma in treatment-naïve patients with chronic hepatitis B following entecavir therapy.

AIMS: This study aimed to evaluate the clinical usefulness of the aminotransferase to platelet ratio index (APRI), fibrosis-4 (FIB-4), and modified FIB-4 (mFIB-4) indices in predicting hepatocellular carcinoma (HCC) in patients receiving entecavir (ETV) treatment. METHODS: Among 1955 patients treated with ETV, a total of 857 treatment-naive chronic hepatitis B patients (424 with liver cirrhosis [LC], 433 without cirrhosis) treated with ETV for more than 1 year were analyzed. RESULTS: Of the 857 patients, 85 (9.9%) patients (77 in the LC group and 8 in the non-LC group) developed HCC during the follow-up period. The median observation period was 6.9 years. Multivariate regression analysis of HCC incidence revealed that the initial mFIB-4 index (hazard ratio [HR] 1.058; 95% confidence interval [CI], 1.007-1.112; p = 0.027) and improvement in the FIB-4 index after 1 year of ETV treatment (HR 0.531; 95% CI, 0.339-0.831; p = 0.006) were independent prognostic factors in the entire cohort. In the LC group, the improvement of the FIB-4 index following ETV treatment (HR 0.491; 95% CI, 0.280-0.861; p = 0.013) was negatively correlated with incidence of HCC. However, the area under the receiver operating characteristic curve of specific cut-off values of the FIB-4 index at baseline and 1 year after ETV treatment were 0.572 (95% CI, 0.504-0.640) and 0.615 (95% CI, 0.546-0.684), respectively. In the non-LC group, none of the invasive fibrosis indices could predict HCC incidence. CONCLUSIONS: The specific cut-off value of the FIB-4 index was not suitable for predicting HCC. However, the improvement in the FIB-4 index after 1 year of ETV therapy could be a predictor of HCC development in cirrhotic patients.

Comparable Incidence of Hepatocellular Carcinoma in Chronic Hepatitis B Patients Treated with Entecavir or Tenofovir.

BACKGROUND/AIMS: Adherence to medication and maintained virologic response (MVR) are related to the risk of adverse clinical outcomes. This study aimed to compare the efficacy of entecavir (ETV) and tenofovir disoproxil fumarate (TDF) in relation to the adverse clinical outcomes among chronic hepatitis B (CHB) patients stratified according to adherence to medication and MVR. METHODS: A total of 1794 treatment-naive CHB patients treated with ETV (n = 894) or TDF (n = 900) for > 1 year were identified. RESULTS: Adherence rates were significantly higher in the TDF than in the ETV (93.4% vs. 89.1%, respectively; P < 0.001). The MVR of ETV and TDF were 64.5% and 71.7%, respectively (P = 0.001). The MVR of ETV and TDF in the good adherence group were 72.1% and 76.4%, respectively (P = 0.083); in the poor adherence group, the MVR of ETV and TDF were 63.0% and 54.0%, respectively (P = 0.384) Multivariate analysis showed that the risk of HCC and death or transplantation was similar between groups (HR 0.826, 95% CI 0.522-1.306; P = 0.413 and HR 0.636, 95% CI 0.258-1.569; P = 0.325, respectively) after adjusting for adherence to medication and MVR. In the 589 propensity-matched pairs of patients, risk of HCC and death or transplantation was similar between treatment groups after stratification according to adherence rates and MVR. CONCLUSIONS: After adjustment for adherence and MVR, ETV, and TDF did not differ in terms of the risk of HCC and death or transplantation in all patients and propensity score-matched cohorts.

Specific fate decisions in adult hepatic progenitor cells driven by MET and EGFR signaling.

The relative contribution of hepatocyte growth factor (HGF)/MET and epidermal growth factor (EGF)/EGF receptor (EGFR), two key signal transduction systems in the normal and diseased liver, to fate decisions of adult hepatic progenitor cells (HPCs) has not been resolved. Here, we developed a robust culture system that permitted expansion and genetic manipulation of cells capable of multilineage differentiation in vitro and in vivo to examine the individual roles of HGF/MET and EGF/EGFR in HPC self-renewal and binary cell fate decision. By employing loss-of-function and rescue experiments in vitro, we showed that both receptors collaborate to increase the self-renewal of HPCs through activation of the extracellular signal-regulated kinase (ERK) pathway. MET was a strong inducer of hepatocyte differentiation by activating AKT and signal transducer and activator of transcription (STAT3). Conversely, EGFR selectively induced NOTCH1 to promote cholangiocyte specification and branching morphogenesis while concomitantly suppressing hepatocyte commitment. Furthermore, unlike the deleterious effects of MET deletion, the liver-specific conditional loss of Egfr facilitated rather than suppressed progenitor-mediated liver regeneration by switching progenitor cell differentiation toward hepatocyte lineage. These data provide new insight into the mechanisms regulating the stemness properties of adult HPCs and reveal a previously unrecognized link between EGFR and NOTCH1 in directing cholangiocyte differentiation.

Genome-Wide SNP Markers for Genotypic and Phenotypic Differentiation of Melon (Cucumis melo L.) Varieties Using Genotyping-by-Sequencing.

Melon (Cucumis melo L.) is an economically important horticultural crop with abundant morphological and genetic variability. Complex genetic variations exist even among melon varieties and remain unclear to date. Therefore, unraveling the genetic variability among the three different melon varieties, muskmelon (C. melo subsp. melo), makuwa (C. melo L. var. makuwa), and cantaloupes (C. melo subsp. melo var. cantalupensis), could provide a basis for evolutionary research. In this study, we attempted a systematic approach with genotyping-by-sequencing (GBS)-derived single nucleotide polymorphisms (SNPs) to reveal the genetic structure and diversity, haplotype differences, and marker-based varieties differentiation. A total of 6406 GBS-derived SNPs were selected for the diversity analysis, in which the muskmelon varieties showed higher heterozygote SNPs. Linkage disequilibrium (LD) decay varied significantly among the three melon varieties, in which more rapid LD decay was observed in muskmelon (r2 = 0.25) varieties. The Bayesian phylogenetic tree provided the intraspecific relationships among the three melon varieties that formed, as expected, individual clusters exhibiting the greatest genetic distance based on the posterior probability. The haplotype analysis also supported the phylogeny result by generating three major networks for 48 haplotypes. Further investigation for varieties discrimination allowed us to detect a total of 52 SNP markers that discriminated muskmelon from makuwa varieties, of which two SNPs were converted into cleaved amplified polymorphic sequence markers for practical use. In addition to these markers, the genome-wide association study identified two SNPs located in the genes on chromosome 6, which were significantly associated with the phenotypic traits of melon seed. This study demonstrated that a systematic approach using GBS-derived SNPs could serve to efficiently classify and manage the melon varieties in the genebank.

Evaluation of the radiation response and regenerative effects of mesenchymal stem cell-conditioned medium in an intestinal organoid system.

Intestinal organoids have recently emerged as an in vitro model relevant to the gut system owing to their recapitulation of the native intestinal epithelium with crypt-villus architecture. However, it is unclear whether intestinal organoids reflect the physiology of the in vivo stress response. Here, we systemically investigated the radiation response in organoids and animal models using mesenchymal stem cell-conditioned medium (MSC-CM), which contains secreted paracrine factors. Irradiated organoids exhibited sequential induction of viability loss and regrowth after irradiation (within 12 days), similar to the response of the native intestinal epithelium. Notably, treatment with MSC-CM facilitated the reproliferation of intestinal stem cells (ISCs) and restoration of damaged crypt-villus structures in both models. Furthermore, Wnt/Notch signaling pathways were commonly upregulated by MSC-CM, but not radiation, and pharmacologically selective inhibition of Wnt or Notch signaling attenuated the enhanced recovery of irradiated organoids, with increases in ISCs, following MSC-CM treatment. Interestingly, the expression of Wnt4, Wnt7a, and active ß-catenin was increased, but not notch family members, in MSC-CM-treated organoid after irradiation. Treatment of recombinant mouse Wnt4 and Wnt7a after irradiation improved to some extent intestinal epithelial regeneration both in vitro and in vivo. Overall, these results suggested that intestinal organoids recapitulated the physiological stress response of the intestinal epithelium in vivo. Thus, our findings provided important insights into the physiology of intestinal organoids and may contribute to the development of strategies to enhance the functional maturation of engineered organoids.

Non-steroidal anti-inflammatory drug-induced enteropathy as a major risk factor for small bowel bleeding: a retrospective study.

BACKGROUND: Small bowel (SB) bleeding accounts for 5% of all gastrointestinal (GI) bleeding cases and 80% of obscure GI bleeding cases. Although angioectasia is the common etiology of SB bleeding, nonsteroidal anti-inflammatory drug (NSAID)-induced SB lesions are also reported as a major cause in studies from Eastern countries. Herein, we assessed the frequency of occurrence of NSAID-induced SB lesions in Korean patients with obscure GI bleeding. METHODS: We retrospectively analyzed medical records of all consecutive patients aged ≥18 years who underwent capsule endoscopy from March 2018 to February 2019 at Ulsan University Hospital and Kosin University Gospel Hospital. RESULTS: Of the 83 subjects (all Korean; mean age ± standard deviation: 59 ± 18 years; age range: 18-84 years; men: n = 52; women: n = 31), 55 (66.2%) had stool with clear blood and 28 (33.8%) had normal stool with iron deficiency anemia. The detection rate of SB bleeding and lesions using capsule endoscopy was 72.3% (60 of 83 patients). A significantly higher frequency (40 of 51) of ulcerative/erosive lesions than other causes was observed in patients with inactive bleeding but visible SB lesions. As a result, NSAID-induced enteropathy accounted for 30.1% of 83 patients with obscure GI bleeding (25 of the all 60 SB bleeding cases). CONCLUSIONS: Contrary to what is reported for patients in Western countries, this study in Korean patients showed an improved diagnostic yield of capsule endoscopy for obscure GI bleeding and that NSAID-induced enteropathy was the most common etiology of SB bleeding. Aggressive small intestine examination is required for patients with unexplained GI bleeding.

Hyaluronic acid synthase 2 promotes malignant phenotypes of colorectal cancer cells through transforming growth factor beta signaling.

Hyaluronic acid synthase 2 (HAS2) is suggested to play a critical role in malignancy and is abnormally expressed in many carcinomas. However, its role in colorectal cancer (CRC) malignancy and specific signaling mechanisms remain obscure. Here, we report that HAS2 was markedly increased in both CRC tissue and malignant CRC cell lines. Depletion of HAS2 in HCT116 and DLD1 cells, which express high levels of HAS2, critically increased sensitivity of radiation/oxaliplatin-mediated apoptotic cell death. Moreover, downregulation of HAS2 suppressed migration, invasion and metastasis in nude mice. Conversely, ectopic overexpression of HAS2 in SW480 cells, which express low levels of HAS2, showed the opposite effect. Notably, HAS2 loss- and gain-of-function experiments revealed that it regulates CRC malignancy through TGF-ß expression and SMAD2/Snail downstream components. Collectively, our findings suggest that HAS2 contributes to malignant phenotypes of CRC, at least partly, through activation of the TGF-ß signaling pathway, and shed light on the novel mechanisms behind the constitutive activation of HAS2 signaling in CRC, thereby highlighting its potential as a therapeutic target.

Effects of metformin and phenformin on apoptosis and epithelial-mesenchymal transition in chemoresistant rectal cancer.

Recurrence and chemoresistance in colorectal cancer remain important issues for patients treated with conventional therapeutics. Metformin and phenformin, previously used in the treatment of diabetes, have been shown to have anticancer effects in various cancers, including breast, lung and prostate cancers. However, their molecular mechanisms are still unclear. In this study, we examined the effects of these drugs in chemoresistant rectal cancer cell lines. We found that SW837 and SW1463 rectal cancer cells were more resistant to ionizing radiation and 5-fluorouracil than HCT116 and LS513 colon cancer cells. In addition, metformin and phenformin increased the sensitivity of these cell lines by inhibiting cell proliferation, suppressing clonogenic ability and increasing apoptotic cell death in rectal cancer cells. Signal transducer and activator of transcription 3 and transforming growth factor-ß/Smad signaling pathways were more activated in rectal cancer cells, and inhibition of signal transducer and activator of transcription 3 expression using an inhibitor or siRNA sensitized rectal cancer cells to chemoresistant by inhibition of the expression of antiapoptotic proteins, such as X-linked inhibitor of apoptosis, survivin and cellular inhibitor of apoptosis protein 1. Moreover, metformin and phenformin inhibited cell migration and invasion by suppression of transforming growth factor ß receptor 2-mediated Snail and Twist expression in rectal cancer cells. Therefore, metformin and phenformin may represent a novel strategy for the treatment of chemoresistant rectal cancer by targeting signal transducer and activator of transcription 3 and transforming growth factor-ß/Smad signaling.

Small molecule-mediated reprogramming of human hepatocytes into bipotent progenitor cells.

BACKGROUND & AIMS: Currently, much effort is directed towards the development of new cell sources for clinical therapy using cell fate conversion by small molecules. Direct lineage reprogramming to a progenitor state has been reported in terminally differentiated rodent hepatocytes, yet remains a challenge in human hepatocytes. METHODS: Human hepatocytes were isolated from healthy and diseased donor livers and reprogrammed into progenitor cells by 2 small molecules, A83-01 and CHIR99021 (AC), in the presence of EGF and HGF. The stemness properties of human chemically derived hepatic progenitors (hCdHs) were tested by standard in vitro and in vivo assays and transcriptome profiling. RESULTS: We developed a robust culture system for generating hCdHs with therapeutic potential. The use of HGF proved to be an essential determinant of the fate conversion process. Based on functional evidence, activation of the HGF/MET signal transduction system collaborated with A83-01 and CHIR99021 to allow a rapid expansion of progenitor cells through the activation of the ERK pathway. hCdHs expressed hepatic progenitor markers and could self-renew for at least 10 passages while retaining a normal karyotype and potential to differentiate into functional hepatocytes and biliary epithelial cells in vitro. Gene expression profiling using RNAseq confirmed the transcriptional reprogramming of hCdHs towards a progenitor state and the suppression of mature hepatocyte transcripts. Upon intrasplenic transplantation in several models of therapeutic liver repopulation, hCdHs effectively repopulated the damaged parenchyma. CONCLUSION: Our study is the first report of successful reprogramming of human hepatocytes to a population of proliferating bipotent cells with regenerative potential. hCdHs may provide a novel tool that permits expansion and genetic manipulation of patient-specific progenitors to study regeneration and the repair of diseased livers. LAY SUMMARY: Human primary hepatocytes were reprogrammed towards hepatic progenitor cells by a combined treatment with 2 small molecules, A83-01 and CHIR99021, and HGF. Chemically derived hepatic progenitors exhibited a high proliferation potential and the ability to differentiate into hepatocytes and biliary epithelial cells both in vitro and in vivo. This approach enables the generation of patient-specific hepatic progenitors and provides a platform for personal and stem cell-based regenerative medicine.

Association between non-alcoholic fatty liver disease and subclinical coronary atherosclerosis: An observational cohort study.

BACKGROUND & AIMS: There are limited data on the association between non-alcoholic fatty liver disease (NAFLD) and subclinical coronary atherosclerosis. This study investigated the influence of NAFLD on subclinical coronary atherosclerosis as detected by coronary computed tomography angiography (CCTA) in an asymptomatic population. METHODS: A total of 5,121 consecutive asymptomatic individuals with no prior history of coronary artery disease or significant alcohol intake voluntarily underwent abdominal ultrasonography and CCTA as part of a general health examination. Fatty liver was assessed by ultrasonography examination. The fatty liver index and NAFLD fibrosis score were also calculated. Coronary atherosclerotic plaques on CCTA were evaluated. The association between NAFLD and subclinical coronary atherosclerosis was determined by logistic regression analysis. RESULTS: Of the study participants, 1,979 (38.6%) had ultrasonography-diagnosed NAFLD. After adjustment for cardiovascular risk factors, there were no statistically significant differences in the adjusted odds ratios of NAFLD for calcified plaque (1.03; 95% CI 0.89-1.20; p = 0.673) and mixed plaque (1.15; 95% CI 0.93-1.42; p = 0.214). However, adjusted odds ratios for any atherosclerotic plaque (1.18; 95% CI 1.03-1.35; p = 0.016) and non-calcified plaque (1.27; 95% CI 1.08-1.48; p = 0.003) were significantly higher in NAFLD. In addition, there was a significant association of fatty liver index ≥30 with non-calcified plaque (1.37; 95% CI 1.14-1.65; p = 0.001) and NAFLD fibrosis score ≥-1.455 with non-calcified plaque (1.20; 95% CI 1.08-1.42; p = 0.030). CONCLUSIONS: In this large cross-sectional study of asymptomatic individuals undergoing CCTA, NAFLD was consistently associated with non-calcified plaque, suggesting an increased cardiovascular risk. LAY SUMMARY: In asymptomatic individuals, non-alcoholic fatty liver disease (NAFLD) was an independent risk factor for non-calcified plaque, which has been known as a vulnerable plaque associated with sudden and unexpected cardiac events. Therefore, appropriate medical therapy for NAFLD was required to reduce future cardiac events.

Medication Nonadherence Increases Hepatocellular Carcinoma, Cirrhotic Complications, and Mortality in Chronic Hepatitis B Patients Treated With Entecavir.

OBJECTIVES: Optimal adherence to nucleoside analogue treatment is necessary to achieve undetectable levels of hepatitis B virus (HBV) DNA in patients with chronic hepatitis B (CHB), and to prevent cirrhotic complications. However, any large long-term follow-up study has not been investigated the effect of adherence to entecavir (ETV) treatment on specific liver-related events (LREs), namely, hepatocellular carcinoma (HCC), cirrhotic complications, and mortality. METHODS: This was a 10-year longitudinal observational study of treatment-naïve patients with CHB who received ETV treatment. The primary outcome was the cumulative probability of LREs. The cumulative level of adherence to medication was categorized as good (≥90%) or poor (<90%). RESULTS: Data from 894 treatment-naïve CHB patients who received ETV were analyzed. Overall mean adherence rates were 89.1%. Patients with poor adherence had a higher risk of virologic breakthrough (VBT) (HR, 22.42; 95% CI, 19.57-52.52; P < 0.001) than those with good adherence. Multivariate analyses showed a higher risk of liver-related (HR, 14.29; 95% CI, 3.49-58.47; P < 0.001) or all-cause (HR, 4.96; 95% CI, 2.19-11.27; P < 0.001) mortality, HCC (HR, 2.86; 95% CI, 1.76-4.64; P < 0.001), and cirrhotic complications (HR, 2.86; 95% CI, 1.93-4.25; P < 0.001) with poor adherence. Medication adherence was further stratified into three groups according to adherence rates of <70%, ≥70 to <90%, and ≥90%. The dose-response analyses of adherence rates showed that the risk of LREs increased progressively as medication adherence declined. In particular, the unfavorable effects of nonadherence were more pronounced in patients with cirrhosis. CONCLUSIONS: Poor adherence to medication was associated with a higher mortality and greater risk of HCC and cirrhotic complications, particularly among patients with liver cirrhosis.

Mapping of a major quantitative trait locus for bakanae disease resistance in rice by genome resequencing.

Bakanae disease (BD) has emerged as a serious threat in almost all rice cultivation regions worldwide. Nampyeong is a Korean japonica rice variety known to be resistant to BD. In this study, quantitative trait locus (QTL) mapping was performed with F2 and F3 plants derived from a cross between the Nampyeong variety and a susceptible Korean japonica line, DongjinAD. First, resequencing of Nampyeong and DongjinAD was performed, which identified 171,035 single nucleotide polymorphisms (SNPs) between the two parental varieties. Using these SNPs, 161 cleaved amplified polymorphic sequence (CAPS) markers and six derived CAPS markers were developed; then, a genetic map was constructed from the genotypes of 180 plants from the DongjinAD/Nampyeong F2 plants. The total length of the constructed genetic map was 1386 cM, with an average interval of 8.9 cM between markers. The BD mortality rates of each F3 family were measured by testing 40 F3 progenies using in vitro seedling screening method. QTL analysis based on the genetic map and mortality rate data revealed a major QTL, qFfR1, on rice chromosome 1. qFfR1 was located at 89.8 cM with a logarithm of the odds (LOD) score of 22.7. Further, there were three markers at this point: JNS01033, JNS01037, and JNS01041. A total of 15 genes were identified with annotations related to defense against plant diseases among the 179 genes in the qFfR1 interval at 95% probability, thereby providing potential candidate genes for qFfR1. qFfR1 and its closely linked markers will be useful in breeding rice varieties resistant to BD.

Mortality, liver transplantation and hepatic complications in patients with treatment-naïve chronic hepatitis B treated with entecavir vs tenofovir.

Few studies have directly compared the long-term clinical outcomes of entecavir (ETV) and tenofovir disoproxil fumarate (TDF). This study aimed to compare the risk of mortality, liver transplantation and hepatic complications including hepatocellular carcinoma (HCC) and hepatic decompensation between these drugs in treatment-naïve chronic hepatitis B (CHB). We performed a longitudinal observational analysis of data from 1325 consecutive adult CHB patients with a cumulative adherence of ≥80% to treatment with ETV (n = 721) or TDF (n = 604) at a tertiary referral hospital in Ulsan, Korea, from 1 January 2007 through 31 April 2017. Among the patients, 708 were analysed using propensity score matching with a ratio of 1:1. In the follow-up period of up to 5 years, five patients (0.4%) died, three patients (0.2%) underwent liver transplantation (LT) and 54 patients (4.1%) developed HCC. Hepatic decompensation occurred in 24 (1.8%) patients. ETV therapy did not significantly differ from TDF therapy regarding the risk of liver-related death or LT (HR 0.96; 95% CI, 0.23-4.07; log-rank P = 0.955), HCC (HR, 1.36; 95% CI, 0.72-2.56; log-rank P = 0.340) and hepatic decompensation (HR, 1.64; 95% CI, 0.67-4.00; log-rank P = 0.276). In the 708 propensity-matched pairs, ETV and TDF were also not significantly different with respect to the risk of mortality, LT and hepatic complications. In this longitudinal observational study of 1325 patients with CHB, ETV and TDF therapies were not significantly different regarding the risk of mortality, HCC, LT and hepatic decompensation.

The risk of hepatocellular carcinoma within and beyond the first 5 years of entecavir in Korean patients with chronic hepatitis B.

BACKGROUND & AIMS: The development of hepatocellular carcinoma (HCC) in patients with chronic hepatitis B (CHB) has decreased due to potent antiviral agents. However, it remains uncertain whether the risk of HCC will diminish after long-term antiviral therapy in Asia, where CHB is endemic and vertical transmission is common. This study aimed to compare the incidence of HCC within and beyond the first 5 years of entecavir (ETV) in treatment-naïve Korean patients with CHB. METHODS: We performed a retrospective observational analysis of data from 894 consecutive, adult patients with CHB undergoing ETV treatment at a tertiary referral hospital in Ulsan, Korea from January 1, 2007 through April 31, 2017. We compared the HCC incidence rates per 100 person-years within and beyond the first 5 years. Univariate and multivariate analyses for factors predictive of HCC were performed. RESULTS: The incidence rate of HCC in patients with CHB did not differ statistically when we compared within and beyond the first 5 years of ETV therapy (2.29% vs 1.66% per person-year, P = 0.217). Failure to achieve maintained virological response (MVR) was a major independent risk factor for HCC in patients at a follow-up of <5 years. In contrast, in patients with a follow-up of ≥5 years, achieving MVR was not significantly associated with HCC development. CONCLUSIONS: The incidence rate of HCC may not change significantly before and after 5 years of ETV therapy in Korean CHB patients. The risk of HCC in Asian CHB patients may remain in the long-term.

Rebamipide ameliorates radiation-induced intestinal injury in a mouse model.

Radiation-induced enteritis is a major side effect in cancer patients undergoing abdominopelvic radiotherapy. Radiation exposure produces an uncontrolled inflammatory cascade and epithelial cell loss leading to impaired epithelial barrier function. The goal of this study was to determine the effect of rebamipide on regeneration of the intestinal epithelia after radiation injury. The abdomens of C57BL/6 mice were exposed to 13Gy of irradiation (IR) and then the mice were treated with rebamipide. Upon IR, intestinal epithelia were destroyed structurally at the microscopic level and bacterial translocation was increased. The intestinal damage reached a maximum level on day 6 post-IR and intestinal regeneration occurred thereafter. We found that rebamipide significantly ameliorated radiation-induced intestinal injury. In mice treated with rebamipide after IR, intestinal barrier function recovered and expression of the tight junction components of the intestinal barrier were upregulated. Rebamipide administration reduced radiation-induced intestinal mucosal injury. The levels of proinflammatory cytokines and matrix metallopeptidase 9 (MMP9) were significantly reduced upon rebamipide administration. Intestinal cell proliferation and ß-catenin expression also increased upon rebamipide administration. These data demonstrate that rebamipide reverses impairment of the intestinal barrier by increasing intestinal cell proliferation and attenuating the inflammatory response by inhibiting MMP9 and proinflammatory cytokine expression in a murine model of radiation-induced enteritis.