Interferon-γ induces autophagy with growth inhibition and cell death in human hepatocellular carcinoma (HCC) cells through interferon-regulatory factor-1 (IRF-1)

Oncolytic vaccinia virus harboring aphrocallistes vastus lectin exerts anti-tumor effects by directly oncolysis and inducing immune response through enhancing ROS in human ovarian cancer

Aphrocallistes vastus lectin (AVL) is a Ca2+ dependent C-type lectin produced by sponges. Previous studies have demonstrated that oncolytic vaccinia virus harboring AVL (oncoVV-AVL) effectively triggers cell death in various tumors. However, the effects of oncoVV-AVL on human ovarian cancer (OV) remain unknown. This study aims to investigate the mechanism-of-action of oncoVV-AVL in human OV cell lines and in tumor-bearing nude mice. We found that oncoVV-AVL could directly induce apoptosis and autophagy in ovarian cancer cells. Additionally, our results showed that oncoVV-AVL increased the serum levels of mouse IFN-γ (mIFN-γ), leading to the activation of M1-polarized macrophages. Conversely, NADPH, a reducing agent by providing reducing equivalents, reduced the production of mIFN-γ, and suppressed M1-polarization of macrophage. Based on these findings, we propose that oncoVV-AVL not only contributes to direct cytolysis, but also enhances host immune response by promoting ROS levels.

Key role of interferon regulatory factor 1 (IRF-1) in regulating liver disease: progress and outlook

Interferon regulatory factor 1 (IRF-1) is a member of the IRF family. It is the first transcription factor to be identified that could bind to the interferon-stimulated response element (ISRE) on the target gene and displays crucial roles in the interferon-induced signals and pathways. IRF-1, as an important medium, has all of the advantages of full cell cycle regulation, cell death signaling transduction, and reinforcing immune surveillance, which are well documented. Current studies indicate that IRF-1 is of vital importance to the occurrence and evolution of multifarious liver diseases, including but not limited to inhibiting the replication of the hepatitis virus (A/B/C/E), alleviating the progression of liver fibrosis, and aggravating hepatic ischemia-reperfusion injury (HIRI). The tumor suppression of IRF-1 is related to the clinical characteristics of liver cancer patients, which makes it a potential indicator for predicting the prognosis and recurrence of liver cancer; additionally, the latest studies have revealed other effects of IRF-1 such as protection against alcoholic/non-alcoholic fatty liver disease (AFLD/NAFLD), cholangiocarcinoma suppression, and uncommon traits in other liver diseases that had previously received little attention. Intriguingly, several compounds and drugs have featured a protective function in specific liver disease models in which there is significant involvement of the IRF-1 signal. In this paper, we hope to propose a prospective research basis upon which to help decipher translational medicine applications of IRF-1 in liver disease treatment.

Immune checkpoint inhibitors in colorectal cancer: limitation and challenges

Colorectal cancer exhibits a notable prevalence and propensity for metastasis, but the current therapeutic interventions for metastatic colorectal cancer have yielded suboptimal results. ICIs can decrease tumor development by preventing the tumor's immune evasion, presenting cancer patients with a new treatment alternative. The increased use of immune checkpoint inhibitors (ICIs) in CRC has brought several issues. In particular, ICIs have demonstrated significant clinical effectiveness in patients with MSI-H CRC, whereas their efficacy is limited in MSS. Acquired resistance can still occur in patients with a positive response to ICIs. This paper describes the efficacy of ICIs currently in the clinical treatment of CRC, discusses the mechanisms by which acquired resistance occurs, primarily related to loss and impaired presentation of tumor antigens, reduced response of IFN-λ and cytokine or metabolic dysregulation, and summarizes the incidence of adverse effects. We posit that the future of ICIs hinges upon the advancement of precise prediction biomarkers and the implementation of combination therapies. This study aims to elucidate the constraints associated with ICIs in CRC and foster targeted problem-solving approaches, thereby enhancing the potential benefits for more patients.

A novel approach to design chimeric multi epitope vaccine against Leishmania exploiting infected host cell proteome

Leishmaniasis is a major infectious disease having high mortality which could be attributed to lack of a suitable vaccine candidate. We propose a novel approach to design multiepitope vaccine to leishmaniasis exploiting specific membrane proteome from infected macrophage from host. The MHC-I, MHC-II and BC epitopes predicted for unique proteins from the infected macrophages and Leishmania and a MEV designed in various combinations (1a-1m). The epitope arrangements 1a, 1k, 1l, and 1 m showed a strong antigenicity profile and immune response. The molecular dynamics simulation indicate the 1k, 1l, and 1 m constructs have strong affinity toward TLR-2, TLR-3, and TLR-4. Overall the structural and immunogenicity profile suggests 1k is top candidate. Further, a computational model system with TLR-2, TLR-3, TLR-4, BCR, MHC-I and MHC-II was generated for 1k construct to understand the MEV interactions with immune components. Dihedral distribution and distance was enumerated to understand the movement of immune components towards 1k. The results indicate 1k has strong affinity for the immune response molecules especially TLR-3, BCR and MHC-II are coming in close contact with the MEV through the simulation. The study suggests that designed multi-epitope vaccine 1k has potential to induce proper immune response but warrants further studies.

Immune Regulatory Networks and Therapy of γδ T Cells in Liver Cancer: Recent Trends and Advancements

The roles of γδ T cells in liver cancer, especially in the potential function of immunotherapy due to their direct cytotoxic effects on tumor cells and secretion of important cytokines and chemokines, have aroused research interest. This review briefly describes the basic characteristics of γδ T cells, focusing on their diverse effects on liver cancer. In particular, different subtypes of γδ T cells have diverse or even opposite effects on liver cancer. We provide a detailed description of the immune regulatory network of γδ T cells in liver cancer from two aspects: immune components and nonimmune components. The interactions between various components in this immune regulatory network are dynamic and pluralistic, ultimately determining the biological effects of γδ T cells in liver cancer. We also integrate the current knowledge of γδ T-cell immunotherapy for liver cancer treatment, emphasizing the potential of these cells in liver cancer immunotherapy.

Cooperative STAT3-NFkB signaling modulates mitochondrial dysfunction and metabolic profiling in hepatocellular carcinoma

BACKGROUND

Hepatocellular carcinoma (HCC) continues to pose a significant health challenge and is often diagnosed at advanced stages. Metabolic reprogramming is a hallmark of many cancer types, including HCC and it involves alterations in various metabolic or nutrient-sensing pathways within liver cells to facilitate the rapid growth and progression of tumours. However, the role of STAT3-NFκB in metabolic reprogramming is still not clear.

APPROACH AND RESULTS

Diethylnitrosamine (DEN) administered animals showed decreased body weight and elevated level of serum enzymes. Also, Transmission electron microscopy (TEM) analysis revealed ultrastructural alterations. Increased phosphorylated signal transducer and activator of transcription-3 (p-STAT3), phosphorylated nuclear factor kappa B (p-NFκβ), dynamin related protein 1 (Drp-1) and alpha-fetoprotein (AFP) expression enhance the carcinogenicity as revealed in immunohistochemistry (IHC). The enzyme-linked immunosorbent assay (ELISA) concentration of IL-6 was found to be elevated in time dependent manner both in blood serum and liver tissue. Moreover, immunoblot analysis showed increased level of p-STAT3, p-NFκβ and IL-6 stimulated the upregulation of mitophagy proteins such as Drp-1, Phosphatase and tensin homolog (PTEN)-induced putative kinase 1 (PINK-1). Meanwhile, downregulation of Poly [ADP-ribose] polymerase 1 (PARP-1) and cleaved caspase 3 suppresses apoptosis and enhanced expression of AFP supports tumorigenesis. The mRNA level of STAT3 and Drp-1 was also found to be significantly increased. Furthermore, we performed high-field 800 MHz Nuclear Magnetic Resonance (NMR) based tissue and serum metabolomics analysis to identify metabolic signatures associated with the progression of liver cancer. The metabolomics findings revealed aberrant metabolic alterations in liver tissue and serum of 75th and 105th days of intervention groups in comparison to control, 15th and 45th days of intervention groups. Tissue metabolomics analysis revealed the accumulation of succinate in the liver tissue samples, whereas, serum metabolomics analysis revealed significantly decreased circulatory levels of ketone bodies (such as 3-hydroxybutyrate, acetate, acetone, etc.) and membrane metabolites suggesting activated ketolysis in advanced stages of liver cancer.

CONCLUSION

STAT3-NFκβ signaling axis has a significant role in mitochondrial dysfunction and metabolic alterations in the development of HCC.

Structural changes and anti-hepatocellular carcinoma activity of interferon-γ after interaction with sinensetin

Exploring the interaction of small molecules with therapeutic proteins can provide useful information about development of ligand-protein complexes as synergistically therapeutic platforms. In this study, the interaction of sinensetin with human interferon gamma (IFNγ) was evaluated experimentally and theoretically. Also, the synergistic effects of IFNγ- sinensetin complex on the inhibition of hepatocellular carcinoma HepG2 cell proliferation were assessed by cell viability and quantitative real time PCR assays. It was realized that sinensetin interacts with IFNγ through a static quenching mechanism and hydrophobic forces mediated by presence of Lys55 and Lys58 amino acid residues in the binding site were the main contributing forces in the spontaneous formation of IFNγ-sinensetin complex. Also, the interaction of sinensetin with IFNγ did not induce a significant change in the secondary and tertiary structure of the protein. Cellular assays revealed a synergistic effect of sinensetin on IFNγ -triggered anticancer action in HepG2 cells through overexpression of caspase-3 mRNA and protein. In conclusion, this study may hold great promise for the development of potential ligand- protein complexes for therapeutic purposes.

Normalization of the ATP1A1 Signalosome Rescinds Epigenetic Modifications and Induces Cell Autophagy in Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is the third leading cause of cancer-related death worldwide. In metabolic dysfunction-associated steatohepatitis (MASH)-related HCC, cellular redox imbalance from metabolic disturbances leads to dysregulation of the α1-subunit of the Na/K-ATPase (ATP1A1) signalosome. We have recently reported that the normalization of this pathway exhibited tumor suppressor activity in MASH-HCC. We hypothesized that dysregulated signaling from the ATP1A1, mediated by cellular metabolic stress, promotes aberrant epigenetic modifications including abnormal post-translational histone modifications and dysfunctional autophagic activity, leading to HCC development and progression. Increased H3K9 acetylation (H3K9ac) and H3K9 tri-methylation (H3K9me3) were observed in human HCC cell lines, HCC-xenograft and MASH-HCC mouse models, and epigenetic changes were associated with decreased cell autophagy in HCC cell lines. Inhibition of the pro-autophagic transcription factor FoxO1 was associated with elevated protein carbonylation and decreased levels of reduced glutathione (GSH). In contrast, normalization of the ATP1A1 signaling significantly decreased H3K9ac and H3K9me3, in vitro and in vivo, with concomitant nuclear localization of FoxO1, heightening cell autophagy and cancer-cell apoptotic activities in treated HCC cell lines. Our results showed the critical role of the ATP1A1 signalosome in HCC development and progression through epigenetic modifications and impaired cell autophagy activity, highlighting the importance of the ATP1A1 pathway as a potential therapeutic target for HCC.

Fluid shear stress enhances natural killer cell's cytotoxicity toward circulating tumor cells through NKG2D-mediated mechanosensing

Tumor cells metastasize to distant organs mainly via hematogenous dissemination, in which circulating tumor cells (CTCs) are relatively vulnerable, and eliminating these cells has great potential to prevent metastasis. In vasculature, natural killer (NK) cells are the major effector lymphocytes for efficient killing of CTCs under fluid shear stress (FSS), which is an important mechanical cue in tumor metastasis. However, the influence of FSS on the cytotoxicity of NK cells against CTCs remains elusive. We report that the death rate of CTCs under both NK cells and FSS is much higher than the combined death induced by either NK cells or FSS, suggesting that FSS may enhance NK cell's cytotoxicity. This death increment is elicited by shear-induced NK activation and granzyme B entry into target cells rather than the death ligand TRAIL or secreted cytokines TNF-α and IFN-γ. When NK cells form conjugates with CTCs or adhere to MICA-coated substrates, NK cell activating receptor NKG2D can directly sense FSS to induce NK activation and degranulation. These findings reveal the promotive effect of FSS on NK cell's cytotoxicity toward CTCs, thus providing new insight into immune surveillance of CTCs within circulation.

The role of interferon-gamma and its receptors in gastrointestinal cancers

Gastrointestinal malignancies are the most prevalent type of cancer around the world. Even though numerous studies have evaluated gastrointestinal malignancies, the actual underlying mechanism is still unknown. These tumors have a poor prognosis and are frequently discovered at an advanced stage. Globally, there is an increase in the incidence and mortality of gastrointestinal malignancies, including those of the stomach, esophagus, colon, liver, and pancreas. Growth factors and cytokines are signaling molecules that are part of the tumor microenvironment and play a significant role in the development and spread of malignancies. IFN-γ induce its effects by activation of intracellular molecular networks. The main pathway involved in IFN-γ signaling is the JAK/STAT pathway, which regulates the transcription of hundreds of genes and mediates various biological responses. IFN-γ receptor is composed of two IFN-γR1 chains and two IFN-γR2 chains. Binding to IFN-γ, causes the intracellular domains of IFN-γR2 to oligomerize and transphosphorylate with IFN-γR1 which activates downstream signaling components: JAK1 and JAK2. These activated JAKs phosphorylate the receptor, creating binding sites for STAT1. STAT1 is then phosphorylated by JAK, resulting in the formation of STAT1 homodimers (gamma activated factors or GAFs) that translocate to the nucleus and regulate gene expression. The balance between positive and negative regulation of this pathway is crucial for immune responses and tumorigenesis. In this paper, we evaluate the dynamic roles of IFN- γ and its receptors in gastrointestinal cancers and present evidence that inhibiting IFN- γ signaling may be an effective treatment strategy.

Gender Differences in the Pathogenesis and Risk Factors of Hepatocellular Carcinoma

Several chronic liver diseases are characterized by a clear gender disparity. Among them, hepatocellular carcinoma (HCC) shows significantly higher incidence rates in men than in women. The different epidemiological distribution of risk factors for liver disease and HCC only partially accounts for these gender differences. In fact, the liver is an organ with recognized sexual dysmorphism and is extremely sensitive to the action of androgens and estrogens. Sex hormones act by modulating the risk of developing HCC and influencing its aggressiveness, response to treatments, and prognosis. Furthermore, androgens and estrogens are able to modulate the action of other factors and cofactors of liver damage (e.g., chronic HBV infection, obesity), significantly influencing their carcinogenic power. The purpose of this review is to examine the factors related to the different gender distribution in the incidence of HCC as well as the pathophysiological mechanisms involved, with particular reference to the central role played by sex hormones.

TRIM13 inhibits cell proliferation and induces autophagy in lung adenocarcinoma by regulating KEAP1/NRF2 pathway

Lung adenocarcinoma (LUAD) is the most common type of lung cancer. Tripartite motif 13 (TRIM13) is a member of TRIM protein family and is downregulated in multiple cancers, especially non-small cell lung cancers (NSCLC). In this study, we investigated anti-tumor mechanism of TRIM13 in non-small cell lung cancer tissues and cell lines. First, the mRNA and protein levels of TRIM13 in LUAD tissue and cells were measured. TRIM13 was overexpressed on LUAD cells to investigate the effects on cell proliferation, apoptosis, oxidative stress, p62 ubiquitination, and autophagy activation. Finally, mechanistic role of TRIM13 in regulating the Keap1/Nrf2 pathway was investigated. Results indicated that low level of TRIM13 mRNA and protein expression was found in LUAD tissue and cells. Overexpression of TRIM13 in LUAD cancer cells suppressed their proliferation, increased apoptosis, and oxidative stress, ubiquitinated p62, and activated autophagy via the RING finger domain of TRIM13. Furthermore, TRIM13 showed interaction with p62 and mediated its ubiquitination and degradation in LUAD cells. Mechanistically, TRIM13 exerted the tumor suppressor functions in LUAD cells by negatively regulating Nrf2 signaling and downstream antioxidants, which was further confirmed by in vivo data from xenografts. In conclusion, TRIM13 behaves like a tumor suppressor and triggers autophagy in LUAD cells by mediating p62 ubiquitination via KEAP1/Nrf2 pathway. Our findings provide a novel insight into targeted therapy plans for LUAD.

Inhibition of Checkpoint Kinase 1 (CHK1) Upregulates Interferon Regulatory Factor 1 (IRF1) to Promote Apoptosis and Activate Anti-Tumor Immunity via MICA in Hepatocellular Carcinoma (HCC)

BACKGROUND

CHK1 is considered a key cell cycle checkpoint kinase in DNA damage response (DDR) pathway to communicate with several signaling pathways involved in the tumor microenvironment (TME) in numerous cancers. However, the mechanism of CHK1 signaling regulating TME in hepatocellular carcinoma (HCC) remains unclear.

METHODS

CHK1 expression in HCC tissue was determined by IHC staining assay. DNA damage and apoptosis in HCC cells induced by cisplatin or CHK1 inhibition were detected by WB and flow cytometry. The interaction of CHK1 and IRF1 was analyzed by single-cell RNA-sequence, WB, and immunoprecipitation assay. The mechanism of IRF1 regulating MICA was investigated by ChIP-qPCR.

RESULTS

CHK1 expression is upregulated in human HCC tumors compared to the background liver. High CHK1 mRNA level predicts advanced tumor stage and worse prognosis. Cisplatin and CHK1 inhibition augment cellular DNA damage and apoptosis. Overexpressed CHK1 suppresses IRF1 expression through proteolysis. Furthermore, single-cell RNA-sequence analyses confirmed that MICA expression positively correlated with IRF1 in HCC cells. Immunoprecipitation assay showed the binding between CHK1 and IRF1. Cisplatin and CHK1 inhibition upregulate MICA expression through IRF1-mediated transcriptional effects. A novel specific cis-acting IRF response element was identified at -1756 bp in the MICA promoter region that bound IRF1 to induce MICA gene transcription. MICA may increase NK cell and CD8+T cell infiltration in HCC.

CONCLUSIONS

DNA damage regulates the interaction of CHK1 and IRF1 to activate anti-tumor immunity via the IRF1-MICA pathway in HCC.

Growth Arrest of Alveolar Cells in Response to Cytokines from Spike S1-Activated Macrophages: Role of IFN-γ

Acute respiratory distress syndrome (ARDS) is characterized by severe hypoxemia and high-permeability pulmonary edema. A hallmark of the disease is the presence of lung inflammation with features of diffuse alveolar damage. The molecular pathogenetic mechanisms of COVID-19-associated ARDS (CARDS), secondary to SARS-CoV-2 infection, are still not fully understood. Here, we investigate the effects of a cytokine-enriched conditioned medium from Spike S1-activated macrophage on alveolar epithelial A549 cells in terms of cell proliferation, induction of autophagy, and expression of genes related to protein degradation. The protective effect of baricitinib, employed as an inhibitor of JAK-STAT, has been also tested. The results obtained indicate that A549 exhibits profound changes in cell morphology associated to a proliferative arrest in the G0/G1 phase. Other alterations occur, such as a blockade of protein synthesis and the activation of autophagy, along with an increase of the intracellular amino acids content, which is likely ascribable to the activation of protein degradation. These changes correlate to the induction of IFN-regulatory factor 1 (IRF-1) due to an increased secretion of IFN-γ in the conditioned medium from S1-activated macrophages. The addition of baricitinib prevents the observed effects. In conclusion, our findings suggest that the IFN-γ-IRF-1 signaling pathway may play a role in the alveolar epithelial damage observed in COVID-19-related ARDS.

Tumor cell-derived asymmetric dimethylarginine regulates macrophage functions and polarization

BACKGROUND

Asymmetric dimethylarginine (ADMA), which is significantly elevated in the plasma of cancer patients, is formed via intracellular recycling of methylated proteins and serves as a precursor for resynthesis of arginine. However, the cause of ADMA elevation in cancers and its impact on the regulation of tumor immunity is not known.

METHODS

Three mouse breast cell lines (normal breast epithelial HC11, breast cancer EMT6 and triple negative breast cancer 4T1) and their equivalent 3D stem cell culture were used to analyze the secretion of ADMA using ELISA and their responses to ADMA. Bone marrow-derived macrophages and/or RAW264.7 cells were used to determine the impact of increased extracellular ADMA on macrophage-tumor interactions. Gene/protein expression was analyzed through RNAseq, qPCR and flow cytometry. Protein functional analyses were conducted via fluorescent imaging (arginine uptake, tumor phagocytosis) and enzymatic assay (arginase activity). Cell viability was measured via MTS assay and/or direct cell counting using Countess III FL system.

RESULTS

For macrophages, ADMA impaired proliferation and phagocytosis of tumor cells, and even caused death in cultures incubated without arginine. ADMA also led to an unusual macrophage phenotype, with increased expression of arginase, cd163 and cd206 but decreased expression of il10 and dectin-1. In contrast to the severely negative impacts on macrophages, ADMA had relatively minor effects on proliferation and survival of mouse normal epithelial HC11 cells, mouse breast cancer EMT6 and 4T1 cells, but there was increased expression of the mesenchymal markers, vimentin and snail2, and decreased expression of the epithelial marker, mucin-1 in EMT6 cells. When tumor cells were co-cultured ex vivo with tumor antigen in vivo-primed splenocytes, the tumor cells secreted more ADMA and there were alterations in the tumor cell arginine metabolic landscape, including increased expression of genes involved in arginine uptake, metabolism and methylation, and decreased expression of a gene that is responsible for arginine demethylation. Additionally, interferon-gamma, a cytokine involved in immune challenge, increased secretion of ADMA in tumor cells, a process attenuated by an autophagy inhibitor.

CONCLUSION

Our results suggest initial immune attack promotes autophagy in tumor cells, which then secrete ADMA to manipulate macrophage polarization favoring tumor tolerance.

HDAC8 Promotes Liver Metastasis of Colorectal Cancer via Inhibition of IRF1 and Upregulation of SUCNR1

Histone deacetylases (HDACs) are well-characterized for their involvement in tumor progression. Herein, the current study set out to unravel the association of HDAC8 with colorectal cancer (CRC). Bioinformatics analyses were carried out to retrieve the expression patterns of HDAC8 in CRC and the underlying mechanism. Following expression determination, the specific roles of HDAC8, IRF1, and SUCNR1 in CRC cell functions were analyzed following different interventions. Additionally, tumor formation and liver metastasis in nude mice were operated to verify the fore experiment. Bioinformatics analyses predicted the involvement of the HDAC8/IRF1/SUCNR1 axis in CRC. In vitro cell experiments showed that HDAC8 induced the CRC cell growth by reducing IRF1 expression. Meanwhile, IRF1 limited SUCNR1 expression by binding to its promoter. SUCNR1 triggered the growth and metastasis of CRC by inhibiting cell autophagy. HDAC8 blocked IRF1-mediated SUCNR1 inhibition and thereby inhibited autophagy, accelerating CRC cell growth. Lastly, HDAC8 facilitated the development of CRC and liver metastasis by regulating the IRF1/SUCNR1 axis in vivo. Taken together, our findings highlighted the critical role for the HDAC8/IRF1/SUCNR1 axis in the regulation of autophagy and the resultant liver metastasis in CRC.

Exploring immunotherapy in colorectal cancer

Chemotherapy combined with or without targeted therapy is the fundamental treatment for metastatic colorectal cancer (mCRC). Due to the adverse effects of chemotherapeutic drugs and the biological characteristics of the tumor cells, it is difficult to make breakthroughs in traditional strategies. The immune checkpoint blockades (ICB) therapy has made significant progress in the treatment of advanced malignant tumors, and patients who benefit from this therapy may obtain a long-lasting response. Unfortunately, immunotherapy is only effective in a limited number of patients with microsatellite instability-high (MSI-H), and segment initial responders can subsequently develop acquired resistance. From September 4, 2014, the first anti-PD-1/PD-L1 drug Pembrolizumab was approved by the FDA for the second-line treatment of advanced malignant melanoma. Subsequently, it was approved for mCRC second-line treatment in 2017. Immunotherapy has rapidly developed in the past 7 years. The in-depth research of the ICB treatment indicated that the mechanism of colorectal cancer immune-resistance has become gradually clear, and new predictive biomarkers are constantly emerging. Clinical trials examining the effect of immune checkpoints are actively carried out, in order to produce long-lasting effects for mCRC patients. This review summarizes the treatment strategies for mCRC patients, discusses the mechanism and application of ICB in mCRC treatment, outlines the potential markers of the ICB efficacy, lists the key results of the clinical trials, and collects the recent basic research results, in order to provide a theoretical basis and practical direction for immunotherapy strategies.

Macrophages disseminate pathogen associated molecular patterns through the direct extracellular release of the soluble content of their phagolysosomes

Recognition of pathogen-or-damage-associated molecular patterns is critical to inflammation. However, most pathogen-or-damage-associated molecular patterns exist within intact microbes/cells and are typically part of non-diffusible, stable macromolecules that are not optimally immunostimulatory or available for immune detection. Partial digestion of microbes/cells following phagocytosis potentially generates new diffusible pathogen-or-damage-associated molecular patterns, however, our current understanding of phagosomal biology would have these molecules sequestered and destroyed within phagolysosomes. Here, we show the controlled release of partially-digested, soluble material from phagolysosomes of macrophages through transient, iterative fusion-fission events between mature phagolysosomes and the plasma membrane, a process we term eructophagy. Eructophagy is most active in proinflammatory macrophages and further induced by toll like receptor engagement. Eructophagy is mediated by genes encoding proteins required for autophagy and can activate vicinal cells by release of phagolysosomally-processed, partially-digested pathogen associated molecular patterns. We propose that eructophagy allows macrophages to amplify local inflammation through the processing and dissemination of pathogen-or-damage-associated molecular patterns.

The detection of conserved motifs by pattern recognition receptors is a crucial component of the innate detection of pathogens and danger signals via conserved pattern recognition receptors. Here the authors define a pathway that transfers partially digested material from the phagolysosomal pathway of macrophages to release at the plasma membrane which is associated with enhanced inflammatory potential, by a process they introduce as eructophagy.

Changes in immune profile affect disease progression in hepatocellular carcinoma

Objective: Hepatocellular carcinoma (HCC) as a chronic liver condition is largely associated with immune responses. Previous studies have revealed that different subsets of lymphocytes play fundamental roles in controlling or improving the development and outcome of solid tumors like HCC. Hence, this study aimed to investigate whether immune system changes were related to disease development in HCC patients. Methods: Peripheral blood mononuclear cells were isolated from 30 HCC patients and 30 healthy volunteers using Ficoll density centrifugation. The isolated cells were stained with different primary antibodies and percentages of different immune cells were determined by flow cytometry. Results: HCC patients indicated significant reductions in the numbers of CD4⁺ cells, Tbet+IFNγ+cells, and GATA+IL-4+cells in peripheral blood in comparison with healthy individuals (p < 0.05). There was no significant change in IL-17+RORγt+cells between patient and healthy groups. In contrast, Foxp3+CD127^lowcell frequency was significantly higher in patients than healthy subjects (p < 0.0001). The numbers of Th1, Th2, and Th17 cells were significantly lower in HCC patients than healthy control (p < 0.0001), although the reduction in Th2 cell numbers was not statistically significant. On the contrary, Treg percentage showed a significant increase in patients compared to healthy subjects (p < 0.0001). Other data revealed that Th1, Th2, and Th17 cell frequencies were significantly higher in healthy individuals than patients with different TNM stages of HCC, with the exception of Th2 in patients with stage II HCC (p < 0.01-0.05). Treg percentage was significantly increased in patients with different TNM stages (p < 0.0001). Among all CD4⁺ T cells, the frequency of Th2 cell was significantly associated with TNM stages of HCC (p < 0.05). Conclusion: Our data provide further evidence to show that immune changes may participate in determining HCC progression and disease outcome. However, it should be mentioned that more investigations are needed to clarify our results and explain possible impacts of other immune cells on the pathogenesis of HCC.

Crosstalk between autophagy and microbiota in cancer progression

Autophagy is a highly conserved catabolic process seen in eukaryotes and is essentially a lysosome-dependent protein degradation pathway. The dysregulation of autophagy is often associated with the pathogenesis of numerous types of cancers, and can not only promote the survival of cancer but also trigger the tumor cell death. During cancer development, the microbial community might predispose cells to tumorigenesis by promoting mucosal inflammation, causing systemic disorders, and may also regulate the immune response to cancer. The complex relationship between autophagy and microorganisms can protect the body by activating the immune system. In addition, autophagy and microorganisms can crosstalk with each other in multifaceted ways to influence various physiological and pathological responses involved in cancer progression. Various molecular mechanisms, correlating the microbiota disorders and autophagy activation, control the outcomes of protumor or antitumor responses, which depend on the cancer type, tumor microenvironment and disease stage. In this review, we mainly emphasize the leading role of autophagy during the interaction between pathogenic microorganisms and human cancers and investigate the various molecular mechanisms by which autophagy modulates such complicated biological processes. Moreover, we also highlight the possibility of curing cancers with multiple molecular agents targeting the microbiota/autophagy axis. Finally, we summarize the emerging clinical trials investigating the therapeutic potential of targeting either autophagy or microbiota as anticancer strategies, although the crosstalk between them has not been explored thoroughly.

Autophagic activation of IRF-1 aggravates hepatic ischemia-reperfusion injury via JNK signaling

Increasing evidence has accrued indicating that autophagy is associated with hepatic ischemia-reperfusion injury (IRI). This report demonstrates that interferon regulatory factor-1 (IRF-1) was upregulated in response to hepatic IRI and was associated with autophagic activation. As a result of these processes, there is an aggravation of liver damage, effects that can be offset by IRF-1 depletion. In addition, these effects of IRF-1 are associated with JNK pathway activation followed by increases in Beclin1 protein levels. This JNK-induced autophagic cell death then leads to cell failure, and plays an important role in liver function damage. We conclude that IRF-1 activates autophagy through JNK-mediated autophagy. Accordingly, these findings indicating that the IRF-1/JNK pathway activates autophagy to exacerbate liver IRI in this mouse model may provide new insights into novel protective therapies for hepatic IRI.

Selective Induction of Cell Death in Human M1 Macrophages by Smac Mimetics Is Mediated by cIAP-2 and RIPK-1/3 through the Activation of mTORC

Inflammatory macrophages have been implicated in many diseases, including rheumatoid arthritis and inflammatory bowel disease. Therefore, targeting macrophage function and activation may represent a potential strategy to treat macrophage-associated diseases. We have previously shown that IFN-γ-induced differentiation of human M0 macrophages toward proinflammatory M1 state rendered them highly susceptible to the cytocidal effects of second mitochondria-derived activator of caspases mimetics (SMs), antagonist of the inhibitors of apoptosis proteins (IAPs), whereas M0 and anti-inflammatory M2c macrophages were resistant. In this study, we investigated the mechanism governing SM-induced cell death during differentiation into M1 macrophages and in polarized M1 macrophages. IFN-γ stimulation conferred on M0 macrophages the sensitivity to SM-induced cell death through the Jak/STAT, IFN regulatory factor-1, and mammalian target of rapamycin complex-1 (mTORC-1)/ribosomal protein S6 kinase pathways. Interestingly, mTORC-1 regulated SM-induced cell death independent of M1 differentiation. In contrast, SM-induced cell death in polarized M1 macrophages is regulated by the mTORC-2 pathway. Moreover, SM-induced cell death is regulated by cellular IAP (cIAP)-2, receptor-interacting protein kinase (RIPK)-1, and RIPK-3 degradation through mTORC activation during differentiation into M1 macrophages and in polarized M1 macrophages. In contrast to cancer cell lines, SM-induced cell death in M1 macrophages is independent of endogenously produced TNF-α, as well as the NF-κB pathway. Collectively, selective induction of cell death in human M1 macrophages by SMs may be mediated by cIAP-2, RIPK-1, and RIPK-3 degradation through mTORC activation. Moreover, blocking cIAP-1/2, mTORC, or IFN regulatory factor-1 may represent a promising therapeutic strategy to control M1-associated diseases.

Autophagy plays a double-edged sword role in liver diseases

As a highly evolutionarily conserved process, autophagy can be found in all types of eukaryotic cells. Such a constitutive process maintains cellular homeostasis in a wide variety of cell types through the encapsulation of damaged proteins or organelles into double-membrane vesicles. Autophagy not only simply eliminates materials but also serves as a dynamic recycling system that produces new building blocks and energy for cellular renovation and homeostasis. Previous studies have primarily recognized the role of autophagy in the degradation of dysfunctional proteins and unwanted organelles. However, there are findings of autophagy in physiological and pathological processes. In hepatocytes, autophagy is not only essential for homeostatic functions but also implicated in some diseases, such as viral hepatitis, alcoholic hepatitis, and hepatic failure. In the present review, we summarized the molecular mechanisms of autophagy and its role in several liver diseases and put forward several new strategies for the treatment of liver disease.

Coronaviruses construct an interconnection way with ERAD and autophagy

Coronaviruses quickly became a pandemic or epidemic, affecting large numbers of humans, due to their structural features and also because of their impacts on intracellular communications. The knowledge of the intracellular mechanism of virus distribution could help understand the coronavirus's proper effects on different pathways that lead to the infections. They protect themselves from recognition and damage the infected cell by using an enclosed membrane through hijacking the autophagy and endoplasmic reticulum-associated protein degradation pathways. The present study is a comprehensive review of the coronavirus strategy in upregulating the communication network of autophagy and endoplasmic reticulum-associated protein degradation.

IFNγ-mediated repression of system xc- drives vulnerability to induced ferroptosis in hepatocellular carcinoma cells

IFNγ released from CD8⁺ T cells or natural killer cells plays a crucial role in antitumor host immunity. Several studies have found that IFNγ is involved in regulating tumor cell proliferation and apoptosis. However, few studies have examined its role in cell ferroptosis. Here, we found that IFNγ treatment enhanced glutathione depletion, promoted cell cycle arrested in G0/G1 phase, increased lipid peroxidation, and sensitized cells to ferroptosis activators. Additionally, IFNγ down-regulated the mRNA and protein levels of SLC3A2 and SLC7A11, two subunits of the glutamate-cystine antiporter system xc^- via activating the JAK/STAT pathway in hepatocellular carcinoma (HCC) cell lines. Furthermore, IFNγ increased reactive oxygen species levels and decreased mitochondiral membrane potential in Bel7402 and HepG2 cells. These changes were accompanied by decreased system xc^- activity. Cancer cells exposed to TGFβ1 for 48 h showed sensitization to IFNγ + erastin-induced ferroptosis, with decreased system xc^- expression. In conclusion, IFNγ repressed system xc^- activation via activating JAK/STAT signaling. Additionally, enhanced lipid peroxidation was associated with altered mitochondrial function in HCC cells. Our findings identified a role for IFNγ in sensitizing HCC cells to ferroptosis, which provided new insights for applying IFNγ as a cancer treatment.

IFN-γ-induced ER stress impairs autophagy and triggers apoptosis in lung cancer cells

Interferon-gamma (IFN-γ) is a major effector molecule of immunity and a common feature of tumors responding to immunotherapy. Active IFN-γ signaling can directly trigger apoptosis and cell cycle arrest in human cancer cells. However, the mechanisms underlying these actions remain unclear. Here, we report that IFN-γ rapidly increases protein synthesis and causes the unfolded protein response (UPR), as evidenced by the increased expression of glucose-regulated protein 78, activating transcription factor-4, and c/EBP homologous protein (CHOP) in cells treated with IFN-γ. The JAK1/2-STAT1 and AKT-mTOR signaling pathways are required for IFN-γ-induced UPR. Endoplasmic reticulum (ER) stress promotes autophagy and restores homeostasis. Surprisingly, in IFN-γ-treated cells, autophagy was impaired at the step of autophagosome-lysosomal fusion and caused by a significant decline in the expression of lysosomal membrane protein-1 and −2 (LAMP-1/LAMP-2). The ER stress inhibitor 4-PBA restored LAMP expression in IFN-γ-treated cells. IFN-γ stimulation activated the protein kinase-like ER kinase (PERK)-eukaryotic initiation factor 2a subunit (eIF2α) axis and caused a reduction in global protein synthesis. The PERK inhibitor, GSK2606414, partially restored global protein synthesis and LAMP expression in cells treated with IFN-γ. We further investigated the functional consequences of IFN-γ-induced ER stress. We show that inhibition of ER stress significantly prevents IFN-γ-triggered apoptosis. CHOP knockdown abrogated IFN-γ-mediated apoptosis. Inhibition of ER stress also restored cyclin D1 expression in IFN-γ-treated cells. Thus, ER stress and the UPR caused by IFN-γ represent novel mechanisms underlying IFN-γ-mediated anticancer effects. This study expands our understanding of IFN-γ-mediated signaling and its cellular actions in tumor cells.

IRF1 Inhibits Autophagy-Mediated Proliferation of Colorectal Cancer via Targeting ATG13

IRF1 is a nuclear transcription factor that mediates interferon effects and appears to have anti-tumor activity. To determine the roles of IRF1 in colorectal cancer (CRC), we investigated the effects of IRF1 in CRC cells. We found that IRF1 inhibit cell proliferation and tumor growth. Under starvation conditions, IRF1 enhanced apoptosis and reduced autophagic flux. ATG13, an important factor of autophagy complex, was confirmed as a target of IRF1. These findings indicated that IRF1 function as a tumor suppressor in CRC and inhibit autophagy through ATG13, targeting this pathway may provide new insights into the molecular mechanisms of CRC progression.

Identification of new potential antigen recognized by γδT cells in hepatocellular carcinoma

In recent years, the application of chimeric antigen receptor T-cell (CAR-T) therapy based on gamma delta T (γδT) cells in hepatocellular carcinoma (HCC) immunotherapy has attracted more and more attention. However, specific antigens recognized by γδT cells are rarely identified, which has become the main restriction on such therapeutic application of γδT cells. In this report, we identified a new peptide and protein antigen recognized by γδT cells in HCC using our previous established strategy. First, we investigated the diversity of the γ9/δ2 T-cell immunorepertoire by sequence analyses of the expressed complementarity-determining region 3 (CDR3) in HCC patients. Then, we constructed γ9/δ2 T-cell receptor (TCR)-transfected cell lines expressing significant HCC CDR3 sequence and identified a series of peptides capable of binding to γδT cells specifically. Next, we identified, further tested and verified the biological functions of these peptides and their matched protein by bioinformatics analysis. We identified that the new protein hepatocyte growth factor-like protein, also called as macrophage-stimulating protein (MSP), and peptide HP1, not only bound to HCC-predominant γδTCR but also effectively activated γδT cells isolated from HCC patients. Moreover, they could stimulate γδT cells in peripheral blood from HCC patients to produce cytokines, which contributed to inhibiting HCC and played an important role in mediating cytotoxicity to HCC cell lines. In conclusion, we identified MSP and HP1, which showed potential as candidates for antigens recognized by γδT cells in HCC.

Systems Biomedicine of Primary and Metastatic Colorectal Cancer Reveals Potential Therapeutic Targets

Colorectal cancer (CRC) is one of the major causes of cancer deaths across the world. Patients' survival at time of diagnosis depends mainly on stage of the tumor. Therefore, understanding the molecular mechanisms from low-grade to high-grade stages of cancer that lead to cellular migration from one tissue/organ to another tissue/organ is essential for implementing therapeutic approaches. To this end, we performed a unique meta-analysis flowchart by identifying differentially expressed genes (DEGs) between normal, primary (primary sites), and metastatic samples (Colorectal metastatic lesions in liver and lung) in some Test datasets. DEGs were employed to construct a protein-protein interaction (PPI) network. A smaller network containing 39 DEGs was then extracted from the PPI network whose nodes expression induction or suppression alone or in combination with each other would inhibit tumor progression or metastasis. These DEGs were then verified by gene expression profiling, survival analysis, and multiple Validation datasets. We suggested for the first time that downregulation of mitochondrial genes, including ETHE1, SQOR, TST, and GPX3, would help colorectal cancer cells to produce more energy under hypoxic conditions through mechanisms that are different from "Warburg Effect". Augmentation of given antioxidants and repression of P4HA1 and COL1A2 genes could be a choice of CRC treatment. Moreover, promoting active GSK-3β together with expression control of EIF2B would prevent EMT. We also proposed that OAS1 expression enhancement can induce the anti-cancer effects of interferon-gamma, while suppression of CTSH hinders formation of focal adhesions. ATF5 expression suppression sensitizes cancer cells to anchorage-dependent death signals, while LGALS4 induction recovers cell-cell junctions. These inhibitions and inductions would be another combinatory mechanism that inhibits EMT and cell migration. Furthermore, expression inhibition of TMPO, TOP2A, RFC3, GINS1, and CKS2 genes could prevent tumor growth. Besides, TRIB3 suppression would be a promising target for anti-angiogenic therapy. SORD is a poorly studied enzyme in cancer, found to be upregulated in CRC. Finally, TMEM131 and DARS genes were identified in this study whose roles have never been interrogated in any kind of cancer, neither as a biomarker nor curative target. All the mentioned mechanisms must be further validated by experimental wet-lab techniques.

The role of non-apoptotic cell death in the treatment and drug-resistance of digestive tumors

Tumor cell apoptosis evasion is one of the main reasons for easy metastasis occurrence, chemotherapy resistance, and the low five-year survival rate of digestive system tumors. Current research has shown that non-apoptotic cell death plays an important role in tumors of the digestive system. Therefore, increasing the proportion of non-apoptotic tumor cells is one of the effective methods of improving therapeutic efficacies for digestive system tumors. Non-apoptotic cell death modes mainly include autophagic cell death, pyroptosis, ferroptosis, in addition to other cell death modes. This review covers a systematic review relating to the research progress made into autophagic cell death, pyroptosis, ferroptosis, and other cell death modes in the treatment of digestive system tumors. It also highlights how treatment is a reasonable prospect based on clinical experience and provides reliable guidance for the further development of digestive system tumor treatments.

Interferon regulatory factor 1 (IRF-1) downregulates Checkpoint kinase 1 (CHK1) through miR-195 to upregulate apoptosis and PD-L1 expression in Hepatocellular carcinoma (HCC) cells

BACKGROUND

CHK1 is considered an oncogene with overexpression in numerous cancers. However, CHK1 signalling regulation in hepatocellular carcinoma (HCC) remains unclear.

METHODS

CHEK1 mRNA, protein, pri-miR-195 and miR-195 expression in HCC tissue was determined by qPCR, WB and IF staining assay. Survival analyses in HCC with high- and low-CHEK1 mRNA expression was performed using TCGA database. Relative luciferase activity was investigated in HCC cells transfected with p-CHEK1 3'UTR. Apoptosis was detected by TUNEL assay. NK and CD8+ T cells were analysed by flow cytometry.

RESULTS

CHK1 is increased in human HCC tumours compared with non-cancerous liver. High CHK1 predicts worse prognosis. IFN-γ suppresses CHK1 via IRF-1 in HCC cells. The molecular mechanism of IRF-1 suppressing CHK1 is post-transcriptional by promoting miR-195 binding to CHEK1 mRNA 3'UTR, which exerts a translational blockade. Upregulated IRF-1 inhibits CHK1, which induces apoptosis of HCC cells. Likewise, CHK1 inhibition augments cellular apoptosis in HCC tumours. This effect may be a result of increased tumour NK cell infiltration. However, IRF-1 expression or CHK1 inhibition also upregulates PD-L1 expression via increased STAT3 phosphorylation.

CONCLUSIONS

IRF-1 induces miR-195 to suppress CHK1 protein expression. Both increased IRF-1 and decreased CHK1 upregulate cellular apoptosis and PD-L1 expression in HCC.

Interferon regulatory factor 1(IRF-1) activates anti-tumor immunity via CXCL10/CXCR3 axis in hepatocellular carcinoma (HCC)

Interferon regulatory factor 1 (IRF-1) is a tumor suppressor gene in cancer biology with anti-proliferative and pro-apoptotic effect on cancer cells, however mechanisms of IRF-1 regulating tumor microenvironment (TME) in hepatocellular carcinoma (HCC) remain only partially characterized. Here, we investigated that IRF-1 regulates C-X-C motif chemokine 10 (CXCL10) and chemokine receptor 3 (CXCR3) to activate anti-tumor immunity in HCC. We found that IRF-1 mRNA expression was positively correlated with CXCL10 and CXCR3 through qRT-PCR assay in HCC tumors and in analysis of the TCGA database. IRF-1 response elements were identified in the CXCL10 promoter region, and ChIP-qPCR confirmed IRF-1 binding to promote CXCL10 transcription. IRF-2 is a competitive antagonist for IRF-1 mediated transcriptional effects, and overexpression of IRF-2 decreased basal and IFN-γ induced CXCL10 expression. Although IRF-1 upregulated CXCR3 expression in HCC cells, it inhibited proliferation and exerted pro-apoptotic effects, which overcome proliferation partly mediated by activating the CXCL10/CXCR3 autocrine axis. In vitro and in vivo studies showed that IRF-1 increased CD8⁺ T cells, NK and NKT cells migration, and activated IFN-γ secretion in NK and NKT cells to induce tumor apoptosis through the CXCL10/CXCR3 paracrine axis. Conversely, this effect was markedly abrogated in HCC tumor bearing mice deficient in CXCR3. Therefore, the IRF-1/CXCL10/CXCR3 axis contributes to the anti-tumor microenvironment in HCC.

Gene networks and transcriptional regulators associated with liver cancer development and progression

BACKGROUND

Treatment options for hepatocellular carcinoma (HCC) are limited, and overall survival is poor. Despite the high frequency of this malignoma, its basic disease mechanisms are poorly understood. Therefore, the aim of this study was to use different methodological approaches and combine the results to improve our knowledge on the development and progression of HCC.

METHODS

Twenty-three HCC samples were characterized by histological, morphometric and cytogenetic analyses, as well as comparative genomic hybridization (aCGH) and genome-wide gene expression followed by a bioinformatic search for potential transcriptional regulators and master regulatory molecules of gene networks.

RESULTS

Histological evaluation revealed low, intermediate and high-grade HCCs, and gene expression analysis split them into two main sets: GE1-HCC and GE2-HCC, with a low and high proliferation gene expression signature, respectively. Array-based comparative genomic hybridization demonstrated a high level of chromosomal instability, with recurrent chromosomal gains of 1q, 6p, 7q, 8q, 11q, 17q, 19p/q and 20q in both HCC groups and losses of 1p, 4q, 6q, 13q and 18q characteristic for GE2-HCC. Gene expression and bioinformatics analyses revealed that different genes and gene regulatory networks underlie the distinct biological features observed in GE1-HCC and GE2-HCC. Besides previously reported dysregulated genes, the current study identified new candidate genes with a putative role in liver cancer, e.g. C1orf35, PAFAH1B3, ZNF219 and others.

CONCLUSION

Analysis of our findings, in accordance with the available published data, argues in favour of the notion that the activated E2F1 signalling pathway, which can be responsible for both inappropriate cell proliferation and initial chromosomal instability, plays a pivotal role in HCC development and progression. A dedifferentiation switch that manifests in exaggerated gene expression changes might be due to turning on transcriptional co-regulators with broad impact on gene expression, e.g. POU2F1 (OCT1) and NFY, as a response to accumulating cell stress during malignant development. Our findings point towards the necessity of different approaches for the treatment of HCC forms with low and high proliferation signatures and provide new candidates for developing appropriate HCC therapies.

The role of cytokines in the evolution of cancer: IFN-γ paradigm

The evolution of malignant cells implies an increase in oncogenic fitness of cells which arises in active and reciprocal interaction with the tumor microenvironment. The mechanisms facilitating the adaptive evolution of cancer cells involve clonal selection of cancer cells, in a direction of increased adaptive potential under the selective pressure of host defensive strategies. Once reached, this potential could go the other way, changing the same evolutionary force in the tumor microenvironment which influenced its emergence and favoring cancer progression. The immunological system as a part of host defensive mechanisms could be an effective modulator of cancer evolution/progression since it is also a major source of cellular intermediators, such as cytokines. The exemplar of IFN-γ actions during cancer evolution could help the revealing of these mutual interactions and enable better insight into the complex nature of cancer disease, leading to a new approach to treatment strategies.

Probiotic Bacillus subtilis 29,784 improved weight gain and enhanced gut health status of broilers under necrotic enteritis condition

The study investigated the benefit of a Bacillus subtilis probiotic (Bs 29,784) in necrotic enteritis (NE)-challenged broilers. Four treatments were performed with 312 male day-old Ross 308 reared in floor pens from day 0 to day 35: 2 groups fed control diet without or with NE challenge (CtrlNC and CtrlNE); 2 groups fed probiotic and antibiotic supplements in the control diet with NE challenge (ProNE and AntNE). Necrotic enteritis challenge procedures commenced with inoculation of Eimeria spp 1 mL/bird per os at day 9 and Clostridium perfringens EHE-NE18 (approximately 10⁸ cfu/mL) 1 mL/bird per os at day 14 and day 15. Performance parameters were measured on day 16 and day 35. Lesion, cecal microbiota, and jejunal gene expression were analyzed on day 16. Necrotic enteritis challenge significantly suppressed the performance parameters compared with CtrlNC: 27% weight gain reduction, 11 points feed conversion ratio (FCR) increase at day 16, and 12% weight gain reduction, 5-point FCR increase at day 35. By day 35, ProNE and AntNE treatments enabled significantly higher weight gain (4 and 9%, respectively) than CtrlNE. Compared with CtlrNE and contrary to AntNE, ProNE treatment exhibited upregulation of genes coding for tight junctions proteins (CLDN1, JAM2, TJP1), cytokines (IL12, interferon gamma, TGFβ), and Toll-like receptors (TLR5, TLR21) suggesting enhanced immunity and intestinal integrity. 16S NGS analysis of cecal microbiota at day 16 showed a decreased alpha diversity in challenged groups. Principal component analysis of operational taxonomic unit (OTU) abundance revealed that ProNE and AntNE grouped closely while both distantly from CtrlNC and CtrlNE, which were separately grouped, indicating the similar effects of ProNE and AntNE on the OTU diversity that were however different from both CtrlNC and CtrlNE. Microbiota analysis revealed an increase of genera Faecalibacterium, Oscillospira, and Butyricicoccus; and a decrease of genera Ruminococcus, Lactobacillus, and Bacteroides; and an increase of the Firmicutes-to-Bacteroidetes ratio in ProNE and AntNE groups compared with the CtlrNE group. It is concluded that Bs 29,784 may enable improved health of broiler chickens under NE conditions thus performance implications.

Development of a Novel Autophagy-Related Prognostic Signature and Nomogram for Hepatocellular Carcinoma

BACKGROUND

Hepatocellular carcinoma (HCC) is the seventh most common malignancy and the second most common cause of cancer-related deaths. Autophagy plays a crucial role in the development and progression of HCC.

METHODS

Univariate and Lasso Cox regression analyses were performed to determine a gene model that was optimal for overall survival (OS) prediction. Patients in the GSE14520 and GSE54236 datasets of the Cancer Genome Atlas (TCGA) were divided into the high-risk and low-risk groups according to established ATG models. Univariate and multivariate Cox regression analyses were used to identify risk factors for OS for the purpose of constructing nomograms. Calibration and receiver operating characteristic (ROC) curves were used to evaluate model performance. Real-time PCR was used to validate the effects of the presence or absence of an autophagy inhibitor on gene expression in HepG2 and Huh7 cell lines.

RESULTS

OS in the high-risk group was significantly shorter than that in the low-risk group. Gene set enrichment analysis (GSEA) indicated that the association between the low-risk group and autophagy- as well as immune-related pathways was significant. ULK2, PPP3CC, and NAFTC1 may play vital roles in preventing HCC progression. Furthermore, tumor environment analysis via ESTIMATION indicated that the low-risk group was associated with high immune and stromal scores. Based on EPIC prediction, CD8+ T and B cell fractions in the TCGA and GSE54236 datasets were significantly higher in the low-risk group than those in the high-risk group. Finally, based on the results of univariate and multivariate analyses three variables were selected for nomogram development. The calibration plots showed good agreement between nomogram prediction and actual observations. Inhibition of autophagy resulted in the overexpression of genes constituting the gene model in HepG2 and Huh7 cells.

CONCLUSIONS

The current study determined the role played by autophagy-related genes (ATGs) in the progression of HCC and constructed a novel nomogram that predicts OS in HCC patients, through a combined analysis of TCGA and gene expression omnibus (GEO) databases.

The dichotomous role of TGF-β in controlling liver cancer cell survival and proliferation

Hepatocellular carcinoma (HCC) is the major form of primary liver cancer and one of the most prevalent and life-threatening malignancies globally. One of the hallmarks in HCC is the sustained cell survival and proliferative signals, which are determined by the balance between oncogenes and tumor suppressors. Transforming growth factor beta (TGF-β) is an effective growth inhibitor of epithelial cells including hepatocytes, through induction of cell cycle arrest, apoptosis, cellular senescence, or autophagy. The antitumorigenic effects of TGF-β are bypassed during liver tumorigenesis via multiple mechanisms. Furthermore, along with malignant progression, TGF-β switches to promote cancer cell survival and proliferation. This dichotomous nature of TGF-β is one of the barriers to therapeutic targeting in liver cancer. Thereafter, understanding the underlying molecular mechanisms is a prerequisite for discovering novel antitumor drugs that may specifically disable the growth-promoting branch of TGF-β signaling or restore its tumor-suppressive arm. This review summarizes how TGF-β inhibits or promotes liver cancer cell survival and proliferation, highlighting the functional switch mechanisms during the process.

Interferon Regulatory Factor-1 (IRF1) activates autophagy to promote liver ischemia/reperfusion injury by inhibiting β-catenin in mice

Autophagy is an important factor in liver ischemia-reperfusion injury. In the current study we investigate the function of interferon regulatory factor-1 (IRF1) in regulating autophagy to promote hepatic ischemia reperfusion injury (IR). The high expression of IRF1 during hepatic IR exhibited increased liver damage and was associated with activation of autophagy shown by Western blot markers, as well as immunofluorescent staining for autophagosomes. These effects were diminished by IRF1 deficiency in IRF1 knock out (KO) mice. Moreover, the autophagy inhibitor 3-MA decreased IR-induced liver necrosis and markedly abrogated the rise in liver injury tests (AST/ALT). β-catenin expression decreased during liver IR and was increased in the IRF1 KO mice. Immunoprecipitation assay showed the binding between IRF1 and β-catenin. Overexpression of IRF1 induced autophagy and also inhibited the expression of β-catenin. β-catenin inhibitor increased autophagy while β-catenin agonist suppressed autophagy in primary mouse hepatocytes. These results indicate that IRF1 induced autophagy aggravates hepatic IR injury in part by inhibiting β-catenin and suggests that targeting IRF1 may be an effective strategy in reducing hepatic IR injury.

Apolipoprotein L1 is transcriptionally regulated by SP1, IRF1 and IRF2 in hepatoma cells

Apolipoprotein L1 (APOL1) participates in lipid metabolism. Here, we investigate the mechanisms regulating APOL1 gene expression in hepatoma cells. We demonstrate that the -80-nt to +31-nt region of the APOL1 promoter, which contains one SP transcription factor binding GT box and an interferon regulatory factor (IRF) binding ISRE element, maintains the maximum activity. Mutation of the GT box and ISRE element dramatically reduces APOL1 promoter activity. EMSA and chromatin immunoprecipitation assay reveal that the transcription factors Sp1, IRF1 and IRF2 could interact with their cognate binding sites on the APOL1 promoter. Overexpression of Sp1, IRF1 and IRF2 increases promoter activity, leading to increased APOL1 mRNA and protein levels, while knockdown of Sp1, IRF1 and IRF2 has the opposite effects. These results demonstrate that the APOL1 gene could be regulated by Sp1, IRF1 and IRF2 in hepatoma cells.

Interferon regulatory factor 1 (IRF-1) and IRF-2 regulate PD-L1 expression in hepatocellular carcinoma (HCC) cells

The objective response rate of immune checkpoint blockade (ICB) in hepatocellular carcinoma (HCC) with anti PD-L1/PD-1 therapy is low. Discovering the signaling pathways regulating PD-L1 might help to improve ICB response rates. Here, we investigate transcription factors IRF-1 and IRF-2 signaling pathways regulating PD-L1 in HCC cells. In vivo studies show that IRF-1 and PD-L1 mRNA expression in human HCC tumors are significantly repressed compared with noncancerous background liver. IRF-1, IRF-2, and PD-L1 mRNA expression correlated positively in HCC tumors. Increased IRF-1 mRNA expression was observed in patients with well-differentiated or early stage HCC tumors. In vitro studies show that IFN-γ induces PD-L1 mRNA and protein expression through upregulation of IRF-1 in mouse and human HCC cells. IRF-1, IRF-2, and PD-L1 mRNA expression is upregulated in murine HCC by co-culture with effector T cells from spleen cells incubated with anti-CD3/CD28 antibodies. IRF-2 over-expression down-regulates IFN-γ induced PD-L1 promoter activity and protein levels in a dose-dependent manner. We identify two IRF-1 response elements (IRE1/IRE2) in the upstream 5'-flanking region of the CD274 (PD-L1) gene promoter. Site-directed mutagenesis shows both IRE1 and IRE2 are functional in transfection promoter assays. IRF-1 traditionally functions as tumor suppressor gene. However, these novel findings show a complex role for IRF-1 which upregulates PD-L1 in the inflammatory tumor microenvironment. IRF-1 antagonizes IRF-2 for binding to the IRE promoter element in PD-L1 which gives new insight to the regulation of PD-L1/PD-1 pathways in HCC ICB therapy.

Pristine C60 Fullerene Nanoparticles Ameliorate Hyperglycemia-Induced Disturbances via Modulation of Apoptosis and Autophagy Flux

Diabetes mellitus is a prevalent metabolic disorder associated with multiple complications including neuropathy, memory loss and cognitive decline. Despite a long history of studies on diabetic complications, there are no effective therapeutic strategies for neuroprotection in diabetes. Hyperglycemia-induced imbalance in programmed cell death could initiate a decline in neural tissue cells viability. Various nanomaterials can induce either cell death or cell survival dependent on the type and surface features. Pristine C₆₀ fullerene is a nontoxic nanomaterial, which exhibits antioxidant and cytoprotective properties. However, the precise molecular mechanism with which the C₆₀ nanoparticle exerts cytoprotective effect in diabetic subjects has not yet been fully addressed. Thus, this study aimed to determine whether C₆₀ fullerene prevents oxidative stress impairment and to explore the effects of C₆₀ fullerene on apoptosis and autophagy in diabetes mellitus to clarify its potential mechanisms. These effects have been examined for olive oil extracted C₆₀ fullerene on the hippocampus of STZ diabetic rats. Up-regulation of Caspase-3, Beclin-1 and oxidative stress indexes and down-regulation of Bcl-2 were observed in the brain of STZ-diabetic rats. The exposure to C₆₀ fullerene for a period of 12 weeks ameliorate redox imbalance, hyperglycemia-induced disturbances in apoptosis and autophagy flux via modulation of Caspase-3, Bcl-2, Beclin-1 and LC3I/II contents. Furthermore, C₆₀ fullerene ameliorated the LC3I/II ratio and prevented extremely increased autophagy flux. Contrarily, pristine C₆₀ fullerene had no modulatory effect on all studied apoptotic and autophagy markers in non-diabetic groups. Therefore, oil extracted C₆₀ fullerene exhibits cytoprotective effect in hyperglycemia-stressed hippocampal cells. The presented results confirm that pristine C₆₀ fullerene nanoparticles can protect hippocampal cells against hyperglycemic stress via anti-oxidant, anti-apoptotic effects and amelioration of autophagy flux. Moreover, C₆₀ fullerene regulates a balance of autophagy via BCL-2/Beclin-1 reciprocal expression that could prevent functional disturbances in hippocampus.

Inhibition of Sonic Hedgehog Signaling Suppresses Glioma Stem-Like Cells Likely Through Inducing Autophagic Cell Death

Glioblastoma (GBM) often recurs after radio- and chemotherapies leading to poor prognosis. Glioma stem-like cells (GSCs) contribute to drug resistance and recurrence. Thus, understanding cellular mechanism underlying the growth of GSCs is critical for the treatment of GBM. Here GSCs were isolated from human U87 GBM cells with magnetic-activated cell sorting (MACS) using CD133 as a marker. The CD133⁺ cells highly expressed sonic hedgehog (Shh) and were capable of forming tumor spheroids in vitro and tumor in vivo. Athymic mice received intracranial injection of luciferase transduced parental and CD133⁺ GBM cells was utilized as orthotopic GBM model. Inhibited Shh by LDE225 delayed GBM growth in vivo, and downregulated Ptch1 and Gli1. CD133⁺ cell proliferation was more sensitive to inhibition by LDE225 than that of CD133⁻ cells. Treatment with LDE225 significantly reduced CD133⁺-derived tumor spheroid formation. Large membranous vacuoles appeared in the LDE225-treated cells concomitant with the conversion of LC3-I to LC3-II. In addition, LDE225-induced cell death was mitigated in the presence of autophagy inhibitor 3-methyladenine (3-MA). Tumor growth was much slower in Shh shRNA-knockdown mice than in control RNA-transfected mice. Conversely, tumor growth was faster in Shh overexpressed mice. Furthermore, combination of LDE225 and rapamycin treatment resulted in additive effect on LC3-I to LC3-II conversion and reduction in cell viability. However, LDE225 did not affect the phosphorylated level of mTOR. Similarly, amiodarone, an mTOR-independent autophagy enhancer, reduced CD133⁺ cell viability and tumor spheroid formation in vitro and exhibited anti-tumor activity in vivo. These results suggest that Shh inhibitor induces autophagy of CD133⁺ cells likely through mTOR independent pathway. Targeting Shh signal pathway may overcome chemoresistance and provide a therapeutic strategy for patients with malignant gliomas.

Modulating the Crosstalk between the Tumor and Its Microenvironment Using RNA Interference: A Treatment Strategy for Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is the most common primary liver malignancy with one of the highest mortality rates among solid cancers. It develops almost exclusively in the background of chronic liver inflammation, which can be caused by viral hepatitis, chronic alcohol consumption or an unhealthy diet. Chronic inflammation deregulates the innate and adaptive immune responses that contribute to the proliferation, survival and migration of tumor cells. The continuous communication between the tumor and its microenvironment components serves as the overriding force of the tumor against the body's defenses. The importance of this crosstalk between the tumor microenvironment and immune cells in the process of hepatocarcinogenesis has been shown, and therapeutic strategies modulating this communication have improved the outcomes of patients with liver cancer. To target this communication, an RNA interference (RNAi)-based approach can be used, an innovative and promising strategy that can disrupt the crosstalk at the transcriptomic level. Moreover, RNAi offers the advantage of specificity in comparison to the treatments currently used for HCC in clinics. In this review, we will provide the recent data pertaining to the modulation of a tumor and its microenvironment by using RNAi and its potential for therapeutic intervention in HCC.

MicroRNA-301a (miR-301a) is induced in hepatocellular carcinoma (HCC) and down- regulates the expression of interferon regulatory factor-1

Hepatocellular carcinoma (HCC) tumors evade death in part by downregulating expression of the tumor suppressor gene Interferon regulatory factor-1 (IRF-1). However, the molecular mechanisms accounting for IRF-1 suppression in HCC have not been well described. In this study, we identified a novel microRNA-301a (miR-301a) binding site in the 3'-untranslated region (3'- UTR) of the human IRF-1 gene and hypothesized a functional role for miR-301a in regulating HCC growth. We show that miR-301a is markedly upregulated in primary HCC tumors and HCC cell lines, while IRF-1 is down-regulated in a post-transcriptional manner. MiR-301a regulates basal and inducible IRF-1 expression in HCC cells with an inverse relationship between miR-301a and IRF-1 expression in HCC cells. Chronic hypoxia induces miR-301a in HCC in vitro and decreases IRF-1 expression. Finally, miR-301a inhibition increases apoptosis and decreases HCC cell proliferation. These findings suggest that targeting of IRF-1 by miR-301a contributes to the molecular basis for IRF-1 downregulation in HCC and provides new insight into the regulation of HCC by miRNAs.

Autophagy: A Potential Therapeutic Target of Polyphenols in Hepatocellular Carcinoma

Autophagy is a conserved biological phenomenon that maintains cellular homeostasis through the clearing of damaged cellular components under cellular stress and offers the cell building blocks for cellular survival. Aberrations in autophagy subsidize to various human pathologies, such as dementia, cardiovascular diseases, leishmaniosis, influenza, hepatic diseases, and cancer, including hepatocellular carcinoma (HCC). HCC is the fifth common mortal type of liver cancer globally, with an inhomogeneous topographical distribution and highest incidence tripled in men than women. Existing treatment procedures with liver cancer patients result in variable success rates and poor prognosis due to their drug resistance and toxicity. One of the pathophysiological mechanisms that are targeted during the development of anti-liver cancer drugs is autophagy. Generally, overactivated autophagy may lead to a non-apoptotic form of programmed cell death (PCD) or autophagic cell death or type II PCD. Emerging evidence suggests that manipulation of autophagy could induce type II PCD in cancer cells, acting as a potential tumor suppressor. Hence, altering autophagic signaling offers new hope for the development of novel drugs for the therapy of resistant cancer cells. Natural polyphenolic compounds, including flavonoids and non-flavonoids, execute their anticarcinogenic mechanism through upregulating tumor suppressors and autophagy by modulating canonical (Beclin-1-dependent) and non-canonical (Beclin-1-independent) signaling pathways. Additionally, there is evidence signifying that plant polyphenols target angiogenesis and metastasis in HCC via interference with multiple intracellular signals and decrease the risk against HCC. The current review offers a comprehensive understanding of how natural polyphenolic compounds exhibit their anti-HCC effects through regulation of autophagy, the non-apoptotic mode of cell death.

Autophagy and autophagy-related proteins in cancer

Autophagy, as a type II programmed cell death, plays crucial roles with autophagy-related (ATG) proteins in cancer. Up to now, the dual role of autophagy both in cancer progression and inhibition remains controversial, in which the numerous ATG proteins and their core complexes including ULK1/2 kinase core complex, autophagy-specific class III PI3K complex, ATG9A trafficking system, ATG12 and LC3 ubiquitin-like conjugation systems, give multiple activities of autophagy pathway and are involved in autophagy initiation, nucleation, elongation, maturation, fusion and degradation. Autophagy plays a dynamic tumor-suppressive or tumor-promoting role in different contexts and stages of cancer development. In the early tumorigenesis, autophagy, as a survival pathway and quality-control mechanism, prevents tumor initiation and suppresses cancer progression. Once the tumors progress to late stage and are established and subjected to the environmental stresses, autophagy, as a dynamic degradation and recycling system, contributes to the survival and growth of the established tumors and promotes aggressiveness of the cancers by facilitating metastasis. This indicates that regulation of autophagy can be used as effective interventional strategies for cancer therapy.

NK cell-produced IFN-γ regulates cell growth and apoptosis of colorectal cancer by regulating IL-15

Globally, colorectal cancer (CC) is the third leading cause of mortality associated with cancer. Natural killer (NK) cells are a major class of cells that are responsible for eliminating tumor cells and cytokine production. NK cell-mediated production of interferon gamma (IFN-γ) has antiviral, immunoregulatory and anti-tumor properties. IL-15 is important in linking inflammation with cancer. For instance, IL-15 promotes humoral and cell-mediated immune responses to inhibit tumor growth. IL-15 inhibits colitis-associated colon carcinogenesis by inducing antitumor immunity. However, the effect of NK cell-mediated IFN-γ on IL-15 expression in CC progression remains unknown. mRNA and protein level were detected using reverse transcription-quantitative PCR and western blotting, respectively. IFN-γ concentrations were detected using ELISAs. The cytotoxicity of NK-92 cells on SW480 cells was detected using cytoTox 96^® non-radioactive cytotoxicity assays. Cell apoptosis and cell proliferation was detected using flow cytometry and CCK-8 assays, respectively. IL-2 was used for NK-92 stimulation, IL-15 antibodies were used to neutralize IL-15 bioactivity. For the present study, 21 patients with CC and 21 healthy volunteers were enrolled at the First Affiliated Hospital of Xi'an Jiaotong University. IL-15 mRNA and protein expression were significantly lower in NK cells isolated from the CC group compared with healthy volunteer group. IL-2 enhanced the production/secretion of IFN-γ in addition to enhancing NK-92 cell-mediated killing of SW480 cells. Compared with the control group, NK-92 cells treated with IL-2 alone significantly increased cell apoptosis, BAX expression levels as well as phosphorylated (p)-Janus kinase 2 and p-STAT1 protein levels, whilst reducing cell viability and Bcl-2 protein levels in SW480 cells. These observations were not made when treated with IL-2 and polyclonal antibody (pAb) targeting IL-15. Taken together, NK cell-mediated IFN-γ served a pivotal role in CC by regulating IL-15. The effects of IL-2 induced IFN-γ were abolished by pAb IL-15 treatment. The mechanisms of action behind how IFN-γ regulates IL-2 is unclear, and is a promising area for future research.