ß-hydroxybutyrate restrains colitis-associated tumorigenesis by inhibiting HIF-1α-mediated angiogenesis.

Decreased levels of ß-hydroxybutyrate (BHB), a lipid metabolic intermediate known to slow the progression of colorectal cancer (CRC), have been observed in the colon mucosa of patients with inflammatory bowel diseases (IBD). In particular, patients with recurrent IBD present an increased risk of developing colitis-associated colorectal cancer (CAC). The role and molecular mechanism of BHB in the inflammatory and carcinogenic process of CAC remains unclear. Here, the anti-tumor effect of BHB was investigated in the Azoxymethane (AOM)/Dextran Sulfate Sodium (DSS)-induced CAC model and tumor organoids derivatives. The underlying mechanisms were studied using transcriptome and non-target metabolomic assay and further validated in colon tumor cell lineage CT26 in vitro. The tumor tissues and the nearby non-malignant tissues from colon cancer patients were collected to measure the expression levels of ketogenic enzymes. The exogenous BHB supplement lightened tumor burden and angiogenesis in the CAC model. Notably, transcriptome analysis revealed that BHB effectively decreased the expression of VEGFA in the CAC tumor mucosa. In vitro, BHB directly reduced VEGFA expression in hypoxic-treated CT26 cells by targeting transcriptional factor HIF-1α. Conversely, the deletion of HIF-1α largely reversed the inhibitory effect of BHB on CAC tumorigenesis. Additionally, decreased expression of ketogenesis-related enzymes in tumor tissues were associated with poor survival outcomes in patients with colon cancer. In summary, BHB carries out anti-angiogenic activity in CAC by regulating HIF-1α/VEGFA signaling. These findings emphasize the role of BHB in CAC and may provide novel perspectives for the prevention and treatment of colonic tumors.

Wogonin mitigates acetaminophen-induced liver injury in mice through inhibition of the PI3K/AKT signaling pathway.

ETHNOPHARMACOLOGICAL RELEVANCE: Scutellaria baicalensis Georgi (SBG), a widely used traditional Chinese medicine, exhibits anti-inflammatory and antioxidant properties. Wogonin is one of the primary bioactive components of SBG. Acetaminophen (APAP)-induced liver injury (AILI) represents a prevalent form of drug-induced liver damage and is primarily driven by inflammatory responses and oxidative stress. AIM OF STUDY: To investigate the therapeutic effects of Wogonin on AILI and the underlying mechanisms. MATERIALS AND METHODS: C57BL/6 J mice were pre-treated with Wogonin (1, 2.5, and 5 mg/kg bodyweight) for 3 days, followed by treatment with APAP (300 mg/kg bodyweight). The serum and liver tissue samples were collected at 24 h post-APAP treatment. Bone marrow-derived macrophages and RAW264.7 cells were cultured and pre-treated with Wogonin (5, 10, and 20 µM) for 30 min, followed by stimulation with lipopolysaccharide (LPS; 100 ng/mL) for 3 h. To examine the role of the PI3K/AKT signaling pathway in the therapeutic effect of Wogonin on AILI, mice and cells were treated with LY294002 (a PI3K inhibitor) and MK2206 (an AKT inhibitor). RESULTS: Wogonin pre-treatment dose-dependently alleviated AILI in mice. Additionally, Wogonin suppressed oxidative stress and inflammatory responses. Liver transcriptome analysis indicated that Wogonin primarily regulates immune function and cytokines in AILI. Wogonin suppressed inflammatory responses of macrophages by inhibiting the PI3K/AKT signaling pathway. Consistently, Wogonin exerted therapeutic effects on AILI in mice through the PI3K/AKT signaling pathway. CONCLUSIONS: Wogonin alleviated AILI and APAP-induced hepatotoxicity in mice through the PI3K/AKT signaling pathway.

Dual-Path Graph Neural Network with Adaptive Auxiliary Module for Link Prediction.

Link prediction, which has important applications in many fields, predicts the possibility of the link between two nodes in a graph. Link prediction based on Graph Neural Network (GNN) obtains node representation and graph structure through GNN, which has attracted a growing amount of attention recently. However, the existing GNN-based link prediction approaches possess some shortcomings. On the one hand, because a graph contains different types of nodes, it leads to a great challenge for aggregating information and learning node representation from its neighbor nodes. On the other hand, the attention mechanism has been an effect instrument for enhancing the link prediction performance. However, the traditional attention mechanism is always monotonic for query nodes, which limits its influence on link prediction. To address these two problems, a Dual-Path Graph Neural Network (DPGNN) for link prediction is proposed in this study. First, we propose a novel Local Random Features Augmentation for Graph Convolution Network as a baseline of one path. Meanwhile, Graph Attention Network version 2 based on dynamic attention mechanism is adopted as a baseline of the other path. And then, we capture more meaningful node representation and more accurate link features by concatenating the information of these two paths. In addition, we propose an adaptive auxiliary module for better balancing the weight of auxiliary tasks, which brings more benefit to link prediction. Finally, extensive experiments verify the effectiveness and superiority of our proposed DPGNN for link prediction.

Overexpression of tripartite motif-containing 47 (TRIM47) confers sensitivity to PARP inhibition via ubiquitylation of BRCA1 in triple negative breast cancer cells.

Triple-negative breast cancers (TNBC) frequently harbor defects in DNA double-strand break repair through homologous recombination (HR), such as BRCA1 dysfunction. However, less than 15% of TNBC patients were found to carry BRCA1 mutation, indicating that there are other mechanisms regulating BRCA1-deficient in TNBC. In the current study, we shown that overexpression of TRIM47 correlates with progression and poor prognosis in triple-negative breast cancer. Moreover, we demonstrated that TRIM47 directly interacts with BRCA1 and induces ubiquitin-ligase-mediated proteasome turnover of BRCA1, subsequently leads to a decrease of BRCA1 protein levels in TNBC. Moreover, the downstream gene expression of BRCA1, such as p53, p27, p21 was significantly reduced in the overexpression of TRIM47 cell lines but increased in TRIM47-deleted cells. Functionally, we found that overexpression of TRIM47 in TNBC cells confers an exquisite sensitivity to olaparib, an inhibitor of poly-(ADP-ribose)-polymerase (PARP), but TRIM47 inhibition significantly confers TNBC cells resistance to olaparib both in vitro and in vivo. Furthermore, we showed that overexpression of BRCA1 significant increase the olaparib resistance in TRIM47-overexpression-induced PARP inhibitions sensitivity. Taken together, our results uncover a novel mechanism for BRCA1-deficient in TNBC and targeting TRIM47/BRCA1 axis may be a promising prognostic factor and a valuable therapeutic target for TNBC.

circRNA_103615 contributes to tumor progression and cisplatin resistance in NSCLC by regulating ABCB1.

Lung cancer is one of the main causes of tumor lethality worldwide. Circular RNAs (circRNAs) have essential roles in tumor progression. However, in non-small cell lung carcinoma (NSCLC), the role of circRNAs remains unknown. In the present study, the expression, function and molecular mechanisms of a new circRNA, circRNA_103615, were investigated in NSCLC. Reverse transcription-quantitative PCR (RT-qPCR) was used to detect circRNA_103615 expression levels in NSCLC and normal tissues, as well as in NSCLC cell lines. MTT assay, flow cytometric assay, colony formation assay, and cell migration and invasion assays were used to examine the function of circRNA_103615 in NSCLC cells. MTT assay, colony formation assay, RT-qPCR, and western blotting were used to detect the effect of circRNA_103615 on cisplatin resistance. The results demonstrated that NSCLC cell lines and tissues had increased levels of circRNA_103615 compared with normal cells and normal tissues, respectively. Functionally, silencing of circRNA_103615 by small interfering RNA resulted in suppression of cell growth, migration, and invasion, but promotion of cell apoptosis. In addition, the cisplatin resistance of NSCLC was reversed by the silencing of circRNA_103615. Notably, ATP binding cassette subfamily Bmember 1 (ABCB1) expression was significantly decreased following circRNA_103615 knockdown, and ABCB1 overexpression reversed the effects of circRNA_103615 silencing on NSCLC cisplatin resistance. Thus, the present study indicated that circRNA_103615 may serve as a critical oncogene and potential novel biomarker in NSCLC, as well as a potential cisplatin resistance promoter, by regulating ABCB1 expression.

ARRB2 promotes colorectal cancer growth through triggering WTAP.

Colorectal cancer (CRC) is one of the most lethal cancers worldwide. The expression of ß-arrestin2 (ß-Arr2, ARRB2) in CRC has been well investigated; however, its exact mechanism causing the cancer progression remains unclear. In this study, we discovered that the expression level of ARRB2 was significantly upregulated in CRC as compared to the normal tissues by employing the Cancer Genome Atlas (TCGA) data, western blot analysis, and immunohistochemistry. Furthermore, the level of ARRB2 was correlated with the patients' overall survival by Kaplan-Meier analysis. The higher expression of ARRB2 promoted CRC cell growth, enhanced the cell motility, and blocked cell apoptosis, which is crucial for tumor growth. Lastly, the suppression of ARRB2 expression was enough to attenuate the progression of CRC induced by azoxymethane/dextran sodium sulfate. Interestingly, we also found that the knockdown of ARRB2 decreased several cancer pathways mediated by the expression of Wilms tumor 1 associated protein (WTAP), which led to the inhibition of cell proliferation and migration. Altogether, our results demonstrated that ARRB2 promoted the growth and migration of CRC cells by regulating the WTAP expression.

Intrahepatic cholangiocarcinoma induced M2-polarized tumor-associated macrophages facilitate tumor growth and invasiveness.

BACKGROUND: M2-polarized tumor-associated macrophages (M2-TAMs) have been shown to correlate with the progression of various cancers, including intrahepatic cholangiocarcinoma (ICC). However, the interactions and mechanism between M2 macrophages and ICC are not completely clear. We aimed to clarify whether M2 macrophages promote the malignancy of ICC and its mechanism. METHODS: Two progressive murine models of ICC were used to evaluate the alterations in different macrophage populations and phenotypes. Furthermore, we assessed M2 macrophage infiltration in 48 human ICC and 15 normal liver samples. The protumor functions and the underlying molecular mechanisms of M2 macrophages in ICC were investigated in an in vitro coculture system. RESULTS: We found that the number of M2 macrophages was significantly higher in ICC tissues than in normal bile ducts in the two murine models. M2 macrophage infiltration was highly increased in peritumoral compared with intratumoral regions and normal liver (p < 0.01). ICC cells induced macrophages to differentiate into the M2-TAM phenotype, and coculture with these M2 macrophages promoted ICC cell proliferation, invasion and epithelial-mesenchymal transition (EMT) in vitro. Mechanistically, M2-TAM-derived IL-10 promoted the malignant properties of ICC cells through STAT3 signaling. Furthermore, blockade of IL-10/STAT3 signaling partly rescued the effects of M2 macrophages on ICC. CONCLUSION: Our results indicated that M2-polarized macrophages induced by ICC promote tumor growth and invasiveness through IL-10/STAT3-induced EMT and might be a potential therapeutic target for ICC.

Pyruvate Kinase M2 Tetramerization Protects against Hepatic Stellate Cell Activation and Liver Fibrosis.

Liver fibrosis is an increasing health problem worldwide, for which no effective antifibrosis drugs are available. Although the involvement of aerobic glycolysis in hepatic stellate cell (HSC) activation has been reported, the role of pyruvate kinase M2 (PKM2) in liver fibrogenesis still remains unknown. We examined PKM2 expression and location in liver tissues and primary hepatic cells. The in vitro and in vivo effects of a PKM2 antagonist (shikonin) and its allosteric agent (TEPP-46) on liver fibrosis were investigated in HSCs and liver fibrosis mouse model. Chromatin immunoprecipitation sequencing and immunoprecipitation were performed to identify the relevant molecular mechanisms. PKM2 expression was significantly up-regulated in both mouse and human fibrotic livers compared with normal livers, and mainly detected in activated, rather than quiescent, HSCs. PKM2 knockdown markedly inhibited the activation and proliferation of HSCs in vitro. Interestingly, the PKM2 dimer, rather than the tetramer, induced HSC activation. PKM2 tetramerization induced by TEPP-46 effectively inhibited HSC activation, reduced aerobic glycolysis, and decreased MYC and CCND1 expression via regulating histone H3K9 acetylation in activated HSCs. TEPP-46 and shikonin dramatically attenuated liver fibrosis in vivo. Our findings demonstrate a nonmetabolic role of PKM2 in liver fibrosis. PKM2 tetramerization or suppression could prevent HSC activation and protects against liver fibrosis.

Timeless-Stimulated miR-5188-FOXO1/ß-Catenin-c-Jun Feedback Loop Promotes Stemness via Ubiquitination of ß-Catenin in Breast Cancer.

MicroRNAs (miRNAs) play an essential role in the self-renewal of breast cancer stem cells (BCCs). Our study aimed to clarify the role of proto-oncogene c-Jun-regulated miR-5188 in breast cancer progression and its association with Timeless-mediated cancer stemness. In the present study, we showed that miR-5188 exerted an oncogenic effect by inducing breast cancer stemness, proliferation, metastasis, and chemoresistance in vitro and in vivo. The mechanistic analysis demonstrated that miR-5188 directly targeted FOXO1, which interacted with ß-catenin in the cytoplasm, facilitated ß-catenin degradation, and impaired the nuclear accumulation of ß-catenin, thus stimulating the activation of known Wnt targets, epithelial-mesenchymal transition (EMT) markers, and key regulators of cancer stemness. Moreover, miR-5188 potentiated Wnt/ß-catenin/c-Jun signaling to promote breast cancer progression. Interestingly, c-Jun enhanced miR-5188 transcription to form a positive regulatory loop, and Timeless interacted with Sp1/c-Jun to induce miR-5188 expression by promoting c-Jun-mediated transcription, which further activated miR-5188-FOXO1/ß-catenin-c-Jun loop and facilitated breast cancer progression. Importantly, miR-5188 was upregulated in breast cancer and was positively correlated with poor patient prognosis. This study identifies miR-5188 as a novel oncomiR and provides a new theoretical basis for the clinical use of miR-5188 antagonists in the treatment of breast cancer.

Chemical compound cinobufotalin potently induces FOXO1-stimulated cisplatin sensitivity by antagonizing its binding partner MYH9.

In this study, we present novel molecular mechanisms by which FOXO1 functions as a tumor suppressor to prevent the pathogenesis of nasopharyngeal carcinoma (NPC). First, we observed that FOXO1 not only controlled tumor stemness and metastasis, but also sensitized NPC cells to cisplatin (DDP) in vitro and in vivo. Mechanistic studies demonstrated that FOXO1-induced miR-200b expression through the GSK3ß/ß-catenin/TCF4 network-mediated stimulation of ZEB1, which reduced tumor stemness and the epithelial-mesenchymal transition (EMT) signal. Furthermore, we observed FOXO1 interaction with MYH9 and suppression of MYH9 expression by modulating the PI3K/AKT/c-Myc/P53/miR-133a-3p pathway. Decreased MYH9 expression not only reduced its interactions with GSK3ß, but also attenuated TRAF6 expression, which then decreased the ubiquitin-mediated degradation of GSK3ß protein. Increased GSK3ß expression stimulated the ß-catenin/TCF4/ZEB1/miR-200b network, which increased the downstream tumor stemness and EMT signals. Subsequently, we observed that chemically synthesized cinobufotalin (CB) strongly increased FOXO1-induced DDP chemosensitivity by reducing MYH9 expression, and the reduction in MYH9 modulated GSK3ß/ß-catenin and its downstream tumor stemness and EMT signal in NPC. In clinical samples, the combination of low FOXO1 expression and high MYH9 expression indicated the worst overall survival rates. Our studies demonstrated that CB potently induced FOXO1-mediated DDP sensitivity by antagonizing its binding partner MYH9 to modulate tumor stemness in NPC.

Tyrosine kinase SYK is a potential therapeutic target for liver fibrosis.

Spleen tyrosine kinase (SYK) plays a critical role in immune cell signaling pathways and has been reported as a biomarker for human hepatocellular carcinoma (HCC). We sought to investigate the mechanism by which SYK promotes liver fibrosis and to evaluate SYK as a therapeutic target for liver fibrosis. We evaluated the cellular localization of SYK and the association between SYK expression and liver fibrogenesis in normal, hepatitis B virus (HBV)-infected, hepatitis C virus (HCV)-infected and non-alcoholic steatohepatitis (NASH) liver tissue (n=36, 127, 22 and 30, respectively). A polymerase chain reaction (PCR) array was used to detect the changes in transcription factor (TF) expression in hepatic stellate cells (HSCs) with SYK knockdown. The effects of SYK antagonism on liver fibrogenesis were studied in LX-2 cells, TWNT-4 cells, primary human HSCs, and three progressive fibrosis/cirrhosis animal models, including a CCL4 mouse model, and diethylnitrosamine (DEN) and bile duct ligation (BDL) rat models. We found that SYK protein in HSCs and hepatocytes correlated positively with liver fibrosis stage in human liver tissue. HBV or HCV infection significantly increased SYK and cytokine expression in hepatocytes. Increasing cytokine production further induced SYK expression and fibrosis-related gene transcription in HSCs. Up-regulated SYK in HSCs promoted HSC activation by increasing the expression of specific TFs related to activation of HSCs. SYK antagonism effectively suppressed liver fibrosis via inhibition of HSC activation, and decreased obstructive jaundice and reduced HCC development in animal models. Conclusion: SYK promotes liver fibrosis via activation of HSCs and is an attractive potential therapeutic target for liver fibrosis and prevention of HCC development. (Hepatology 2018).