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Background: Tumor-associated macrophages (TAM) are immunosuppressive cells that contribute to impaired anti-cancer immunity. Iron plays a critical role in regulating macrophage function. However, it is still elusive whether it can drive the functional polarization of macrophages in the context of cancer and how tumor cells affect the iron-handing properties of TAM. In this study, using hepatocellular carcinoma (HCC) as a study model, we aimed to explore the effect and mechanism of reduced ferrous iron in TAM.Methods: TAM from HCC patients and mouse HCC tissues were collected to analyze the level of ferrous iron. Quantitative real-time PCR was used to assess M1 or M2 signature genes of macrophages treated with iron chelators. A co-culture system was established to explore the iron competition between macrophages and HCC cells. Flow cytometry analysis was performed to determine the holo-transferrin uptake of macrophages. HCC samples from The Cancer Genome Atlas (TCGA) were enrolled to evaluate the prognostic value of transferrin receptor (TFRC) and its relevance to tumor-infiltrating M2 macrophages.Results: We revealed that ferrous iron in M2-like TAM is lower than that in M1-like TAM. In vitro analysis showed that loss of iron-induced immunosuppressive M2 polarization of mouse macrophages. Further experiments showed that TFRC, the primary receptor for transferrin-mediated iron uptake, was overexpressed on HCC cells but not TAM. Mechanistically, HCC cells competed with macrophages for iron to upregulate the expression of M2-related genes via induction of HIF-1α, thus contributing to M2-like TAM polarization. We further clarified the oncogenic role of TFRC in HCC patients by TCGA. TFRC is significantly increased in varieties of malignancies, including HCC, and HCC patients with high TFRC levels have considerably shortened overall survival. Also, TFRC is shown to be positively related to tumor-infiltrating M2 macrophages.Conclusions: Collectively, we identified iron starvation through TFRC-mediated iron competition drives functional immunosuppressive polarization of TAM, providing new insight into the interconnection between iron metabolism and tumor immunity. [ABSTRACT FROM AUTHOR]

microRNAs (miRNAs) and miRNA-mediated regulatory networks are promising candidates in the prevention and treatment of cancer, but the role of specific miRNAs involved in hepatocellular carcinoma (HCC) remains to be elusive. Herein, we found that miR-106b-5p is upregulated in both HCC patients' tumor tissues and HCC cell lines. The miR-106b-5p expression level was positively correlated with α-fetoprotein (AFP), hepatitis B surface antigen (HBsAg), and tumor size. Overexpression of miR-106b-5p promoted cell proliferation, migration, cell cycle G1/S transition, and tumor growth, while decreased miR-106b-5p expression had opposite effects. Mechanistic studies showed that B-cell translocation gene 3 (BTG3), a known antiproliferative protein, was a direct target of miR-106b-5p, whose expression level is inversely correlated with miR-106b-5p expression. Moreover, miR-106b-5p positively regulates cell proliferation in a BTG3-dependent manner, resulting in upregulation of Bcl-xL, cyclin E1, and CDK2, as well as downregulation of p27. More importantly, we also demonstrated that miR-106b-5p enhances the resistance to sorafenib treatment in a BTG3-dependent manner. The in vivo findings showed that mice treated with a miR-106b-5p sponge presented a smaller tumor burden than controls, while the mice injected cells treated with miR-106b-5p had more considerable tumor burden than controls. Altogether, these data suggest that miR-106b-5p promotes cell proliferation and cell cycle and increases HCC cells' resistance to sorafenib through the BTG3/Bcl-xL/p27 signaling pathway. [ABSTRACT FROM AUTHOR]

Background: Interferon regulatory factor 2 (IRF-2) acts as an anti-oncogene in gastric cancer (GC); however, the underlying mechanism remains unknown.Methods: This study determined the expression of IRF-2 in GC tissues and adjacent non-tumor tissues using immunohistochemistry (IHC) and explored the predictive value of IRF-2 for the prognoses of GC patients. Cell function and xenograft tumor growth experiments in nude mice were performed to test tumor proliferation ability, both in vitro and in vivo. Chromatin immunoprecipitation sequencing (ChIP-Seq) assay was used to verify the direct target of IRF-2.Results: We found that IRF-2 expression was downregulated in GC tissues and was negatively correlated with the prognoses of GC patients. IRF-2 negatively affected GC cell proliferation both in vitro and in vivo. ChIP-Seq assay showed that IRF-2 could directly activate AMER-1 transcription and regulate the Wnt/β-catenin signaling pathway, which was validated using IHC, in both tissue microarray and xenografted tumor tissues, western blot analysis, and cell function experiments.Conclusions: Increased expression of IRF-2 can inhibit tumor growth and affect the prognoses of patients by directly regulating AMER-1 transcription in GC and inhibiting the Wnt/β-catenin signaling pathway. [ABSTRACT FROM AUTHOR]

Background: Since interferon regulatory factor (IRF) family functions in immune response to viral infection, its role in colorectal cancer (CRC) has not been inspected before. This study tries to investigate members of IRF family using bioinformatics approaches in aspect of differential expressions, biological function, tumor immune infiltration and clinical prognostic value for patients with CRC.Methods: Transcriptome profiles data, somatic mutations and clinical information of CRC were obtained from COAD/READ dataset of The Cancer Genome Atlas (TCGA) as a training set. Gene expression data (GSE17536 and GSE39582) were downloaded from the Gene Expression Omnibus as a validating set. A random forest algorithm was used to score the risk for every case. Analyzing gene and function enrichment, constructing protein-protein interaction and noncoding RNA network, identifying hub-gene, characterizing tumor immune infiltration, evaluating differences in tumor mutational burden (TMB) and sensitivity to chemotherapeutics or immunotherapy were performed by a series of online tools and R packages. Immunohistochemical (IHC) examinations were carried out validation in tissue samples.Results: Principal-component analysis (PCA) suggested that the transcript expression levels of nine members of IRF family differed between normal colorectum and CRC. The risk score constructed by IRF family not only acted as an independent factor for predicting survival in CRC patients with different biological processes, signaling pathways and TMB, but also indicated different immunotherapy response with diverse immune and stromal cells infiltration. IRF3 and IRF7 were upregulated in CRC and suggested a shorter survival time in patients with CRC. Differentially expressed members of IRF family exhibited varying degrees of immune cell infiltration. IHC analysis showed a positive association between IRF3 and IRF7 expression and tumor-infiltrating immune cells, including CD4+ T cell and CD68+ macrophages.Conclusions: On account of differential expression, IRF family members can help to predict both response to immunotherapy and clinical prognosis of patients with CRC. Our bioinformatic investigation not only gives a preliminary picture of the genetic features as well as tumor microenvironment, but it may provide a clue for further experimental exploration and verification on IRF family members in CRC. [ABSTRACT FROM AUTHOR]

Background and aims: Treatment of non‐alcoholic steatohepatitis (NASH) is challenging, because suppressing fibrotic progression has not been achieved consistently by drug candidates currently in clinical trials. The aim of this study was to investigate the molecular interplays underlying NASH‐associated fibrosis in a mouse NASH model and human specimens. Methods: Mice were divided into 4 groups: Controls; NASH (high fat/Calorie diet plus high fructose and glucose in drinking water, HFCD‐HF/G) for 16 weeks; HFCD‐HF/G plus docosahexaenoic acid (DHA) for 16 or 8 weeks. Results: Along with NASH progression, fibrotic deposition was documented in HFCD‐HF/G‐fed mice. Liver succinate content was significantly increased along with decreased expression of succinate dehydrogenase‐A (SDH‐A) in these mice; whereas, GPR‐91 receptor expression was much enhanced in histology compared to control mice, and co‐localized histologically with hepatic stellate cells (HSCs). Succinate content was increased in fatty acid‐overloaded primary hepatocytes with significant oxidant stress and lipotoxicity. Exposure to succinate led to up‐regulation of GPR‐91 receptor in primary and immortalized HSCs. In contrast, suppression of GPR‐91 receptor expression abolished succinate stimulatory role in GPR‐91 expression and extracellular matrix production in HSCs. All these changes were minimized or abrogated by DHA supplementation in vivo or in vitro. Moreover, GPR‐91 receptor expression correlates with severity of fibrosis in human NASH biopsy specimens. Conclusion: Succinate accumulation in steatotoic hepatocytes may result in HSC activation through GPR‐91 receptor signalling in NASH progression, and the cross‐talk between hepatocytes and HSC through GPR‐91 signalling is most likely to be the molecular basis of fibrogenesis in NASH. [ABSTRACT FROM AUTHOR]

Objective: Lactulose is effective in the treatment and prevention of overt hepatic encephalopathy (OHE), but there are limited data on its use on microbiota in relations to minimal hepatic encephalopathy (MHE) recovery. The present study aimed to assess the efficacy of lactulose in recovery of MHE in aspects of cognitive function, quality of life, and impact on intestinal microbiota. Methods: This multicenter, open‐label randomized controlled trial was conducted in 11 teaching hospitals in China. Participants were randomly allocated on a 2:1 basis to receive lactulose (Gp‐L) or no therapy as control (Gp‐NL) for 60 days. The primary endpoint was the MHE reversal rate. Gut microbiota were compared between MHE patients and healthy volunteers, as well as lactulose‐responders and non‐responders. Results: A total of 98 cirrhotic patients were included in the study, with 31 patients in the Gp‐NL group and 67 patients in the Gp‐L group. At day 60, the MHE reversal rate in Gp‐L (64.18%) was significantly higher than that in Gp‐NL (22.58%) (P =.0002) with a relative risk of 0.46 (95% confidence interval 0.32‐0.67). Number needed to treat was 2.4. Further, there was significantly more improvement in physical functioning in Gp‐L (4.62 ± 6.16) than in Gp‐NL (1.50 ± 5.34) (P =.0212). Proteobacteria was significantly higher in MHE patients compared with healthy volunteers (12.27% vs 4.65%, P < .05). Significant differences were found between lactulose responders and non‐responders in Actinobacteria, Bacteroidetes, Firmicutes, and Proteobacteria. Conclusions: Treatment with lactulose significantly improves MHE recovery rate, and gut microbiota change in MHE patients can modulate the effectiveness of this therapy. Chinese Clinical Trial Register (ChiCTR) (ID: ChiCTR‐TRC‐12002342). [ABSTRACT FROM AUTHOR]

Summary: Addition of peginterferon alpha (PEG‐IFN add‐on) to entecavir (ETV) treatment after a short lead‐in phase results in more response than ETV monotherapy in HBeAg‐positive chronic hepatitis B infection (CHB). This study is the first to assess long‐term efficacy of this treatment strategy. Patients who received ETV ± 24 weeks of PEG‐IFN add‐on in a global trial (ARES study) and completed follow‐up were eligible to participate in this observational LTFU study if they had at least one combined HBeAg and HBV DNA measurement beyond week 96 of the ARES study. The primary endpoint was combined response (HBeAg loss and HBV DNA <200 IU/mL) at LTFU. In total, 48 patients treated with PEG‐IFN add‐on and 48 patients treated with ETV monotherapy were included. The median follow‐up duration was 226 (IQR 51) weeks, and 86/96 (90%) patients were initial non‐responders. At LTFU, combined response was present in 13 (27%) vs 11 (23%) patients (P = 0.81), and 1 log10 HBsAg decline in 59% vs 28% (P = 0.02) for PEG‐IFN add‐on and ETV monotherapy, respectively. In 41 initial non‐responders who continued ETV therapy, combined response at LTFU was present in 9 patients (PEG‐IFN add‐on: 5/22 [23%]; ETV monotherapy: 4/19 [21%]). Beyond week 96 of follow‐up, rates of serological response became comparable between PEG‐IFN add‐on and ETV monotherapy. Although in this LTFU study initial non‐responders were overrepresented in the add‐on arm, PEG‐IFN add‐on possibly leads rather to accelerated HBeAg loss than to increased long‐term HBeAg loss rates. [ABSTRACT FROM AUTHOR]

Background: We studied whether 48 weeks of pegylated interferon alfa-2b (peginterferon) add-on therapy increases serological response in hepatitis B virus (HBV) envelope antigen (HBeAg)-positive patients receiving nucleos(t)ide analogue (NA) therapy, compared with continued NA monotherapy.Methods: This randomized trial included HBeAg-positive patients with compensated liver disease who were treated with entecavir/tenofovir for >12 months and had an HBV DNA load of <2000 IU/mL. Patients were randomly assigned in a 1:1 ratio to 48 weeks of peginterferon add-on therapy (n = 39) or continued NA monotherapy (n = 38). Response (defined as HBeAg seroconversion with an HBV DNA load of <200 IU/mL) was assessed at week 48, with responders discontinuing NA therapy at week 72.Results: The primary end point (response at week 96) was achieved in 18% of patients who were assigned peginterferon add-on therapy versus 8% of patients assigned NA monotherapy (P = .31). Among 58 interferon-naive patients, add-on therapy led to a greater frequency of HBeAg seroconversion (30% vs 7%; P = .034) and response (26% vs 7%; P = .068) at week 96, compared with monotherapy. Among 8 responders at week 48 who discontinued NA therapy at week 72, 6 patients (75%) maintained a response until week 96 (4 of 6 [67%] in the add-on therapy group vs 2 of 2 [100%] in the monotherapy group; P = 1.00). Adverse events were mainly related to peginterferon.Conclusion: The primary end point was negative, but peginterferon add-on therapy appeared to result in a greater frequency of HBeAg seroconversion, compared with NA monotherapy, in interferon-naive patients receiving NA therapy.Clinical Trials Registration: NCT01532843. [ABSTRACT FROM AUTHOR]

The cover image is based on the Original Article Succinate-GPR-91 Receptor Signaling Is Responsible for Nonalcoholic Steatohepatitis-Associated Fibrosis: Effects of DHA Supplementation by Jian Wu, Ying Wang, Li Xie et al., https://doi.org/10.1111/liv.14370. GLO:Q18/01apr20:liv14442-toc-0001.jpg PHOTO (COLOR): . gl. [Extracted from the article]