Tubular cell transcriptional intermediary factor 1γ deficiency exacerbates kidney injury-induced tubular cell polyploidy and fibrosis.

Tubulointerstitial fibrosis is considered the final convergent pathway of progressive chronic kidney diseases (CKD) regardless of etiology. However, mechanisms underlying kidney injury-induced fibrosis largely remain unknown. Recent studies have indicated that transcriptional intermediary factor 1γ (TIF1γ) inhibits the progression of fibrosis in other organs. Here, we found that TIF1γ was highly expressed in the cytoplasm and nucleus of the kidney proximal tubule. Interestingly, we found tubular TIF1γ expression was decreased in patients with CKD, including those with diabetes, hypertension, and IgA nephropathy, and in mouse models with experimental kidney fibrosis (unilateral ureteral obstruction [UUO], folic acid nephropathy [FAN], and aristolochic acid-induced nephrotoxicity). Tubule-specific knock out of TIF1γ in mice exacerbated UUO- and FAN-induced tubular cell polyploidy and subsequent fibrosis, whereas overexpression of kidney TIF1γ protected mice against kidney fibrosis. Mechanistically, in tubular epithelial cells, TIF1γ exerted an antifibrotic role via transforming growth factor-ß (TGF-ß)-dependent and -independent signaling. TIF1γ hindered TGF-ß signaling directly by inhibiting the formation and activity of the transcription factor Smad complex in tubular cells, and we discovered that TIF1γ suppressed epidermal growth factor receptor (EGFR) signaling upstream of TGF-ß signaling in tubular cells by ubiquitylating EGFR at its lysine 851/905 sites thereby promoting EGFR internalization and lysosomal degradation. Pharmacological inhibition of EGFR signaling attenuated exacerbated polyploidization and the fibrotic phenotype in mice with tubule deletion of TIF1γ. Thus, tubular TIF1γ plays an important role in kidney fibrosis by suppressing profibrotic EGFR and TGF-ß signaling. Hence, our findings suggest that maintaining homeostasis of tubular TIF1γ may be a new therapeutic option for treating tubulointerstitial fibrosis and subsequent CKD.

LINC01608 activated by YY1 facilitate hepatocellular carcinoma progression by modulating the EGFR/ERK axis.

BACKGROUND: Long non-coding RNAs (LncRNAs) have been demonstrated to associate with a variety of cancers. However, the mechanisms of LncRNAs in hepatocellular carcinoma (HCC) progression are still not fully clarified. METHODS: LINC01608 expression level in HCC and adjacent normal tissues was detected by real-time-quantitively PCR (RT-qPCR) in clinical samples and in situ hybridization (ISH) in tissue microarray. Several functional assays were performed to determine the biological effects of LINC01608 in HCC cells in vitro, while subcutaneous xenograft models and lung metastasis models in nude mice and immunohistochemistry (IHC) results showed the role of LINC01608 in HCC progression in vivo. The combination of LINC01608 with miR-875-5p and target genes was elucidated by dual-luciferase report assays, RNA immunoprecipitation (RIP) assays and fluorescence in situ hybridization (FISH) assays. Finally, bioinformatics analysis and chromatin immunoprecipitation (CHIP) were performed to investigate the mechanism of Yin Yang-1 (YY1) regulating LINC01608 transcription. RESULTS: LINC01608 was overexpressed in HCC tissues, and high LINC01608 expression predicted poor overall survival (OS) and disease-free survival (DFS) in HCC patients. LINC01608 could promote HCC cell proliferation, migration, invasion and epithelial-mesenchymal transition (EMT) in vitro and in vivo. Furthermore, we demonstrated that LINC01608 could sponge to miR-875-5p and activate the EGFR/ERK pathway. Moreover, we identified transcriptional factor YY1 could bind to the promoter of LINC01608 and induce its transcription. CONCLUSION: LINC01608 could serve as a promising prognostic biomarker of HCC. YY1-activated LINC01608 could promote HCC progression by associating with miR-875-5p to induce the EGFR/ERK signalling pathway. This discovery might provide therapeutic strategies for HCC.

TRIM proteins in hepatocellular carcinoma.

The tripartite motif (TRIM) protein family is a highly conserved group of E3 ligases with 77 members known in the human, most of which consist of a RING-finger domain, one or two B-box domains, and a coiled-coil domain. Generally, TRIM proteins function as E3 ligases to facilitate specific proteasomal degradation of target proteins. In addition, E3 ligase independent functions of TRIM protein were also reported. In hepatocellular carcinoma, expressions of TRIM proteins are both regulated by genetic and epigenetic mechanisms. TRIM proteins regulate multiple biological activities and signaling cascades. And TRIM proteins influence hallmarks of HCC. This review systematically demonstrates the versatile roles of TRIM proteins in HCC and helps us better understand the molecular mechanism of the development and progression of HCC.

RNA-seq-based transcriptomic analysis of AHL-induced biofilm and pyocyanin inhibition in Pseudomonas aeruginosa by Lactobacillus brevis.

Quorum sensing (QS) regulates hundreds of genes in Pseudomonas aeruginosa, and many of which encode extracellular virulence factors. Lactobacillus as a probiotic has been verified to inhibit pathogenesis in P. aeruginosa via quenching QS. The objective of this study was to investigate mechanism of the QS quenching function of Lactobacillus via analyzing the gene expression by transcriptome. We previously isolated a Lactobacillus brevis strain 3M004 from an aquafeed and identified the strain has the function of degrading QS molecular AHL (OC12-HSL). The result showed that 3M004 cells/lysate inhibited biofilm and pyocyanin production of P. aeruginosa PA002. The biofilm inhibition rates were 16.92% and 33.0% after treatment by 1 and 2 mg/mL 3M004 lysate, respectively, and the rates for pyocyanin inhibition were 25.16% and 30.75%, respectively. Transcriptomic analysis showed that down-regulation of genes of LasA and LasB in PA002 was essential in regulating the QS system. The biofilm decrease of PA002 seems not only resulted from gene biosynthesizing of polysaccharides but also from other genes regulating components biosynthesis. Pyocyanin biosynthesis appears to be inhibited by down-regulating the key gene of PhzAB on the nonreversing action from chorismite to pyocyanin.

Long-term outcomes of ultrasound-guided percutaneous microwave ablation versus resection for colorectal cancer liver metastases: a propensity-score matched study.

BACKGROUND AND AIMS: Many previous studies comparing liver resection versus thermal ablation for colorectal cancer liver metastases (CRCLM) are subject to severe selection bias. This study aimed to compare the long-term clinical efficacy of ultrasonography-guided percutaneous microwave ablation (PMWA) with resection for CRCLM using propensity score analysis to reduce confounding by indication. METHODS: This retrospective study included 184 patients with CRCLM from January 2012 to June 2017. Treatment effect was estimated after propensity score matching, Descriptive, regression and survival statistics were applied. RESULTS: A lower American Society of Anesthesiologists classification score and higher performance status were found positively associated with resection (p < 0.05). After propensity score matching, the 1-, 2-, and 3-year local tumor progression free survival rates were found to be 60.3%, 19.1%, and 17.6% in the PMWA group, and 72.1%, 35.3%, 26.5% in the resection group, respectively (p = 0.049). The 1-, 3-, 5-, and 7-year overall survival rates in two groups were similar (p = 0.943). In the PMWA group and resection group, the median hospital stay was 1 (0-12) days and 7 (1-27) days (p = 0.005), respectively; major complications occurred in two patients (2%) and 11 patients (12.9%) (p = 0.009), respectively. CONCLUSIONS: After adjusting for factors known to affect treatment choice, no significant difference in overall survival rates was shown after ultrasound-guided PMWA versus resection for CRCLM. The LTPFS rate of the resection group were better than those of the ultrasound-guided PMWA group. However, the ultrasound-guided PMWA group had fewer complications and shorter hospital stay.

Genome-wide screening diagnostic biomarkers and the construction of prognostic model of hepatocellular carcinoma.

Although methods in diagnosis and therapy of hepatocellular carcinoma (HCC) have made significant progress in decades, the overall survival (OS) of HCC remains dissatisfactory, so it is particularly important to find better diagnostic and prognostic biomarkers. In this study, we found a more reliable potential diagnostic biomarkers and constructed a more accurate prognostic evaluation model based on integrated transcriptome sequencing analysis of multiple independent data sets. First, we performed quality evaluation and differential analysis on seven Gene Expression Omnibus (GEO) data sets, and then comprehensively analyzed the differentially expressed genes with a robust rank aggregation algorithm. Next, Least absolute shrinkage and selection operator (LASSO) regression was used to establish an 8-gene prognostic risk score (RS) model. Finally, the prognostic model was further validated in the GEO data set. Also, RS has independence on other clinicopathological characteristics but has similarities in prognostic assessment compared with the T stage. Moreover, the combination of T stage and prognostic RS model based on the 8-gene had a better prognostic evaluation effect. In brief, our research suggest that the prognostic risk model of 8 genes has important clinical significance in HCC patients, and can further enrich the prognostic guidance value of the traditional T stage.

Quorum Quenching Enzyme APTM01, an Acylhomoserine-Lactone Acylase from Marine Bacterium of Pseudoalteromonas tetraodonis Strain MQS005.

Quorum sensing is a system of stimuli and response correlated to population density and involves in pathogen infection, colonization, and pathogenesis. Quorum quenching enzymes as quorum sensing inhibitors have been identified in a number of bacteria and been used to control by triggering the pathogenic phenotype. The marine bacteria of Pseudoalteromonas had wide activity of degrading AHLs as a type of signal molecule associated with quorum sensing. We screened many Pseudoalteromonas strains in large scale to explore genes of quorum quenching enzymes from the China seas by whole-genome sequencing rather than genomic library construction. Nine target strains were obtained and an acylases gene APTM01 from the strain MQS005 belonging to PvdQ type on sub-branch in phylogenetic tree. And the heterogenous host containing the vector with target gene could degrade C10-HSL, C12-HSL and OC12-HSL. The obtained AHL acylase gene would be a candidate quorum quenching gene to apply in some fields. We identified that the strains of Pseudoalteromonas have wide AHL-degrading ability depending on quorum quenching. The strains would be a resource to explore new quorum quenching enzymes.

Isolation of Viable but Non-culturable Bacteria from Printing and Dyeing Wastewater Bioreactor Based on Resuscitation Promoting Factor.

Printing and dyeing wastewater with high content of organic matters, high colority, and poor biochemical performance is hard to be degraded. In this study, we isolated viable but non-culturable (VBNC) bacteria from printing and dyeing wastewater with the culture media contained resuscitation promoting factor (Rpf) protein secreted by Micrococcus luteus, counted the culturable cells number with the most probable number, sequenced 16S rRNA genes, and performed polymerase chain reaction-denaturing gradient gel electrophoresis. It is obviously that the addition of Rpf in the enrichment culture could promote growth and resuscitation of bacteria in VBNC state to obtain more fastidious bacteria significantly. The identified bacteria were assigned to nine genera in the treatment group, while the two strains of Ochrobactrum anthropi and Microbacterium sp. could not be isolated from the control group. The function of isolated strains was explored and these strains could degrade the dye of Congo red. This study provides a new sight into the further study including the present state, composition, formation mechanism, and recovery mechanism about VBNC bacteria in printing and dyeing wastewater, which would promote to understand bacterial community in printing and dyeing wastewater, and to obtain VBNC bacteria from ecological environment.

[Effects of plant fermentation extract (PFE) on biofilms of Pseudomonas aeruginosa].

Objective: We studied the effects of a plant fermentation extract on destroying biofilms of P. aeruginosa, to provide basic information for treatment of P. aeruginosa related infection diseases. Methods: Strains of P. aeruginosa in clinical specimens were isolated by streaking plate method and identified by PCR and sequencing. Virulence factors were examined using reporter strains, and biofilms were measured by test tube method and a confocal laser scanning microscopy. Results: A total of 16 strains of P. aeruginosa were isolated from clinical specimens from a local hospital, among them PA007 strain showed a maximum response when treated with plant fermentation extract. It shows that 1% plant fermentation extract significantly reduced the production of biofilm, pyocyanine and 3-oxo-C12-HSL (P<0.05). Besides, 1% plant fermentation extract also deceased the bioactivity of LasA protease and survival rate of persisters (P<0.05). The qRT-PCR result indicated that the expressions of lasI and pqsA genes were also markedly inhibited at the presence of 1% plant fermentation extract (P<0.05). Conclusion: The studied plant fermentation extract has anti-infection effect against some P. aeruginosa strains, suggesting a great potential to work as natural antibiotics.

Comparative BAC-based physical mapping of Oryza sativa ssp. indica var. 93-11 and evaluation of the two rice reference sequence assemblies.

Reference sequences are sequences that are used for public consultation, and therefore must be of high quality. Using the whole-genome shotgun/next-generation sequencing approach, many genome sequences of complex higher plants have been generated in recent years, and are generally considered reference sequences. However, none of these sequences has been experimentally evaluated at the whole-genome sequence assembly level. Rice has a relatively simple plant genome, and the genome sequences for its two sub-species obtained using different sequencing approaches were published approximately 10 years ago. This provides a unique system for a case study to evaluate the qualities and utilities of published plant genome sequences. We constructed a robust BAC physical map embedding a large number of BAC end sequences forrice variety 93-11. Through BAC end sequence alignments and tri-assembly comparisons of the 93-11 physical map and the two reference sequences, we found that the Nipponbare reference sequence generated using the clone-by-clone approach has a high quality but still contains small artifact inversions and missing sequences. In contrast, the 93-11 reference sequence generated using the whole-genome shotgun approach contains many large and varied assembly errors, such as inversions, duplications and translocations, as well as missing sequences. The 93-11 physical map provides an invaluable resource for evaluation and improvements toward completion of both Nipponbare and 93-11 reference sequences.

Revisiting the chaperonin T-complex protein-1 ring complex in human health and disease: A proteostasis modulator and beyond.

BACKGROUND: Disrupted protein homeostasis (proteostasis) has been demonstrated to facilitate the progression of various diseases. The cytosolic T-complex protein-1 ring complex (TRiC/CCT) was discovered to be a critical player in orchestrating proteostasis by folding eukaryotic proteins, guiding intracellular localisation and suppressing protein aggregation. Intensive investigations of TRiC/CCT in different fields have improved the understanding of its role and molecular mechanism in multiple physiological and pathological processes. MAIN BODY: In this review, we embark on a journey through the dynamic protein folding cycle of TRiC/CCT, unraveling the intricate mechanisms of its substrate selection, recognition, and intriguing folding and assembly processes. In addition to discussing the critical role of TRiC/CCT in maintaining proteostasis, we detail its involvement in cell cycle regulation, apoptosis, autophagy, metabolic control, adaptive immunity and signal transduction processes. Furthermore, we meticulously catalogue a compendium of TRiC-associated diseases, such as neuropathies, cardiovascular diseases and various malignancies. Specifically, we report the roles and molecular mechanisms of TRiC/CCT in regulating cancer formation and progression. Finally, we discuss unresolved issues in TRiC/CCT research, highlighting the efforts required for translation to clinical applications, such as diagnosis and treatment. CONCLUSION: This review aims to provide a comprehensive view of TRiC/CCT for researchers to inspire further investigations and explorations of potential translational possibilities.

M7G-related tumor immunity: novel insights of RNA modification and potential therapeutic targets.

RNA modifications play a pivotal role in regulating cellular biology by exerting influence over distribution features and molecular functions at the post-transcriptional level. Among these modifications, N7-methylguanosine (m7G) stands out as one of the most prevalent. Over recent years, significant attention has been directed towards understanding the implications of m7G modification. This modification is present in diverse RNA molecules, including transfer RNAs, messenger RNAs, ribosomal RNAs, and other noncoding RNAs. Its regulation occurs through a series of specific methyltransferases and m7G-binding proteins. Notably, m7G modification has been implicated in various diseases, prominently across multiple cancer types. Earlier studies have elucidated the significance of m7G modification in the context of immune biology regulation within the tumor microenvironment. This comprehensive review culminates in a synthesis of findings related to the modulation of immune cells infiltration, encompassing T cells, B cells, and various innate immune cells, all orchestrated by m7G modification. Furthermore, the interplay between m7G modification and its regulatory proteins can profoundly affect the efficacy of diverse adjuvant therapeutics, thereby potentially serving as a pivotal biomarker and therapeutic target for combinatory interventions in diverse cancer types.

CREB3 suppresses hepatocellular carcinoma progression by depressing AKT signaling through competitively binding with insulin receptor and transcriptionally activating RNA-binding motif protein 38.

cAMP responsive element binding protein 3 (CREB3), belonging to bZIP family, was reported to play multiple roles in various cancers, but its role in hepatocellular carcinoma (HCC) is still unclear. cAMP responsive element binding protein 3 like 3 (CREB3L3), another member of bZIP family, was thought to be transcription factor (TF) to regulate hepatic metabolism. Nevertheless, except for being TFs, other function of bZIP family were poorly understood. In this study, we found CREB3 inhibited growth and metastasis of HCC in vitro and in vivo. RNA sequencing indicated CREB3 regulated AKT signaling to influence HCC progression. Mass spectrometry analysis revealed CREB3 interacted with insulin receptor (INSR). Mechanistically, CREB3 suppressed AKT phosphorylation by inhibiting the interaction of INSR with insulin receptor substrate 1 (IRS1). In our study, CREB3 was firstly proved to affect activation of substrates by interacting with tyrosine kinase receptor. Besides, CREB3 could act as a TF to transactivate RNA-binding motif protein 38 (RBM38) expression, leading to suppressed AKT phosphorylation. Rescue experiments further confirmed the independence between the two functional manners. In conclusion, CREB3 acted as a tumor suppressor in HCC, which inhibited AKT phosphorylation through independently interfering interaction of INSR with IRS1, and transcriptionally activating RBM38.

Gut microbiome biomarkers in adolescent obesity: a regional study.

Purpose: This study aimed to characterize the gut microbiota in obese adolescents from Shenzhen (China), and evaluate influence of gender on BMI-related differences in the gut microbiome. Methods: Evaluation of physical examination, blood pressure measurement, serological assay and body composition were conducted in 205 adolescent subjects at Shenzhen. Fecal microbiome composition was profiled via high-throughput sequencing of the V3-V4 regions of the 16S rRNA gene. A Random Forest (RF) classifier model was built to distinguish the BMI categories based on the gut bacterial composition. Results: Fifty-six taxa consisting mainly of Firmicutes were identified that having significant associations with BMI; 2 OTUs belonging to Ruminococcaceae and 1 belonging to Lachnospiraceae had relatively strong positive correlations with body fate rate, waistline and most of serum biochemical properties. Based on the 56 BMI-associated OTUs, the RF model showed a robust classification accuracy (AUC 0.96) for predicting the obese phenotype. Gender-specific differences in the gut microbiome composition was obtained, and a lower relative abundance of Odoribacter genus was particularly found in obese boys. Functional analysis revealed a deficiency in bacterial gene contents related to peroxisome and PPAR signaling pathway in the obese subjects for both genders. Conclusions: This study reveals unique features of gut microbiome in terms of microbial composition and metabolic functions in obese adolescents, and provides a baseline for reference and comparison studies. Supplementary Information: The online version contains supplementary material available at 10.1007/s13755-023-00236-9.

Collagen I-DDR1 signaling promotes hepatocellular carcinoma cell stemness via Hippo signaling repression.

Cancer stem cells (CSCs) are a minority population of cancer cells with stemness and multiple differentiation potentials, leading to cancer progression and therapeutic resistance. However, the concrete mechanism of CSCs in hepatocellular carcinoma (HCC) remains obscure. We found that in advanced HCC tissues, collagen I was upregulated, which is consistent with the expression of its receptor DDR1. Accordingly, high collagen I levels accompanied by high DDR1 expression are associated with poor prognoses in patients with HCC. Collagen I-induced DDR1 activation enhanced HCC cell stemness in vitro and in vivo. Mechanistically, DDR1 interacts with CD44, which acts as a co-receptor that amplifies collagen I-induced DDR1 signaling, and collagen I-DDR1 signaling antagonized Hippo signaling by facilitating the recruitment of PP2AA to MST1, leading to exaggerated YAP activation. The combined inhibition of DDR1 and YAP synergistically abrogated HCC cell stemness in vitro and tumorigenesis in vivo. A radiomic model based on T2 weighted images can noninvasively predict collagen I expression. These findings reveal the molecular basis of collagen I-DDR1 signaling inhibiting Hippo signaling and highlight the role of CD44/DDR1/YAP axis in promoting cancer cell stemness, suggesting that DDR1 and YAP may serve as novel prognostic biomarkers and therapeutic targets in HCC.

Structures and biological functions of zinc finger proteins and their roles in hepatocellular carcinoma.

Zinc finger proteins are transcription factors with the finger domain, which plays a significant role in gene regulation. As the largest family of transcription factors in the human genome, zinc finger (ZNF) proteins are characterized by their different DNA binding motifs, such as C2H2 and Gag knuckle. Different kinds of zinc finger motifs exhibit a wide variety of biological functions. Zinc finger proteins have been reported in various diseases, especially in several cancers. Hepatocellular carcinoma (HCC) is the third leading cause of cancer-associated death worldwide, especially in China. Most of HCC patients have suffered from hepatitis B virus (HBV) and hepatitis C virus (HCV) injection for a long time. Although the surgical operation of HCC has been extremely developed, the prognosis of HCC is still very poor, and the underlying mechanisms in HCC tumorigenesis are still not completely understood. Here, we summarize multiple functions and recent research of zinc finger proteins in HCC tumorigenesis and progression. We also discuss the significance of zinc finger proteins in HCC diagnosis and prognostic evaluation.

DDR1 promotes hepatocellular carcinoma metastasis through recruiting PSD4 to ARF6.

Discoidin domain receptor 1 (DDR1) is a member of the receptor tyrosine kinase family, and its ligand is collagen. Previous studies demonstrated that DDR1 is highly expressed in many tumors. However, its role in hepatocellular carcinoma (HCC) remains obscure. In this study, we found that DDR1 was upregulated in HCC tissues, and the expression of DDR1 in TNM stage II-IV was higher than that in TNM stage I in HCC tissues, and high DDR1 expression was associated with poor prognosis. Gene expression analysis showed that DDR1 target genes were functionally involved in HCC metastasis. DDR1 positively regulated the migration and invasion of HCC cells and promoted lung metastasis. Human Phospho-Kinase Array showed that DDR1 activated ERK/MAPK signaling pathway. Mechanically, DDR1 interacted with ARF6 and activated ARF6 through recruiting PSD4. The kinase activity of DDR1 was required for ARF6 activation and its role in metastasis. High expression of PSD4 was associated with poor prognosis in HCC. In summary, our findings indicate that DDR1 promotes HCC metastasis through collagen induced DDR1 signaling mediated PSD4/ARF6 signaling, suggesting that DDR1 and ARF6 may serve as novel prognostic biomarkers and therapeutic targets for metastatic HCC.

Discoidin domain receptor 1 promotes hepatocellular carcinoma progression through modulation of SLC1A5 and the mTORC1 signaling pathway.

PURPOSE: Hepatocellular carcinoma (HCC) is one of the most common cancers in the world with a high mortality rate. Receptor tyrosine kinases play important roles in the occurrence and development of various cancers. Discoid protein domain receptor 1 (DDR1) is a special type of transmembrane receptor tyrosine kinase. Here, we show that the expression of DDR1 is significantly increased in HCC and is related to a poor clinical prognosis. METHODS: The expression of DDR1 in HCC cell lines and primary HCC specimens was evaluated using Western blotting and immunohistochemistry. A correlation between DDR1 and SLC1A5 expression was also investigated in primary HCC specimens. Cell proliferation was evaluated using in vitro CCK8 and colony formation assays. Gene knock-down and overexpression assays, CHX, NH4CL and Mg132 interference tests and immunoprecipitation, as well as nude mouse xenograft models were used to assess the mechanism by which DDR1 promotes tumorigenesis in vitro and in vivo. RESULTS: We found that DDR1 promotes the proliferation of HCC cells and accelerates the growth of HCC tumor xenografts, while DDR1 downregulation had the opposite effect. We also found that loss or gain of DDR1 expression affected HCC cell cycle progression. Mechanistically, we found that DDR1 interacts with SLC1A5, which belongs to the solute carrier (SLC) family of transporters, and regulates its stability, thereby affecting the mTORC1 signaling pathway. In addition, we found that SLC1A5 regulation by DDR1 can be restored by lysosome inhibitors. We also found that DDR1 is highly expressed in HCC tissues and that increased DDR1 expression predicts a shorter overall survival (OS) time. We additionally found that the expression of SLC1A5 was positively correlated with that of DDR1. Together, our data indicate that DDR1 acts as a tumor-promoting factor that can control HCC cell proliferation and cell cycle progression by stabilizing SLC1A5 in a lysosome-dependent way. CONCLUSIONS: Our study reveals a new mechanism by which DDR1 plays a liver cancer-promoting role. We also found that DDR1 expression serves as an independent prognostic marker, and that DDR1 and SLC1A5 expression levels are positively correlated in clinical samples. Our findings provide a new perspective for understanding HCC development and offers new targets for the treatment and management of HCC.

Circular RNA circUBE2J2 acts as the sponge of microRNA-370-5P to suppress hepatocellular carcinoma progression.

Accumulating evidences indicate that circular RNAs (circRNAs), a class of non-coding RNAs, play important roles in tumorigenesis. However, the function of circRNAs in hepatocellular carcinoma is largely unknown. CircRNA microarray was performed to identify abnormally expressed circRNAs in HCC tissue samples. We conducted Kaplan-Meier survival analysis to explore the significance of circUBE2J2 in clinical prognosis. Then, we examined the functions of circUBE2J2 in HCC by cell proliferation, migration, and mouse xenograft assay. We identified miR-370-5P as a circUBE2J2-related microRNA by using biotin-labeled circUBE2J2 probe to perform RNA antisense purification (RAP) assay in HCC cells. The dual luciferase reporter assay and RNA pulldown assays were employed to verify the relationships among circUBE2J2, miRNA-370-5P, and KLF7. Microarray analysis and qRT-PCR verified a circRNA termed circUBE2J2 that was downregulated in HCC. Kaplan-Meier survival analysis showed that downregulated circUBE2J2 was correlated with poorer survival. CircUBE2J2 expression in HCC cells was selectively regulated via luciferase reporter assays; circUBE2J2 and KLF7 were observed to directly bind to miR-370-5P. Furthermore, knockdown of circUBE2J2 in HCC could downregulate KLF7, the target of miR-370-5P, thus promoting the proliferation and migration of HCC cells. Then the related experiment suggested that circUBE2J2 could regulate the expression of KLF7 by sponging miR-370-5p. In summary, we infer that circUBE2J2 may act as a competing endogenous RNA (ceRNA) to regulate KLF7 expression through sponging miR-370-5P and play a regulatory functions in HCC. CircUBE2J2 may be a diagnostic biomarker and potential target for HCC therapy.

Microenvironment characterization and multi-omics signatures related to prognosis and immunotherapy response of hepatocellular carcinoma.

BACKGROUND: Immune cell infiltration in the tumor microenvironment (TME) affects tumor initiation, patients' prognosis and immunotherapy strategies. However, their roles and interactions with genomics and molecular processes in hepatocellular carcinoma (HCC) still have not been systematically evaluated. METHODS: We performed unsupervised clustering of total 1000 HCC samples including discovery and validation group from available public datasets. Immune heterogeneity of each subtype was explored by multi-dimension analysis. And a support vector machine (SVM) model based on multi-omics signatures was trained and tested. Finally, we performed immunohistochemistry to verify the immune role of signatures. RESULTS: We defined three immune subtypes in HCC, with diverse clinical, molecular, and genomic characteristics. Cluster1 had worse prognosis, better anti-tumor characteristics and highest immune scores, but also accompanied by immunosuppression and T cell dysfunction. Meanwhile, a better anti-PD1/CTLA4 immunotherapeutic response was predicted in cluster1. Cluster2 was enriched in TAM-M2 and stromal cells, indicating immunosuppression. Cluster3, with better prognosis, had lowest CD8 T cell but highest immune resting cells. Further, based on genomic signatures, we developed an SVM classifier to identify the patient's immunological status, which was divided into Type A and Type B, in which Type A had poorer prognosis, higher T cell dysfunction despite higher T cell infiltration, and had better immunotherapeutic response. At the same time, MMP9 may be a potential predictor of the immune characteristics and immunotherapeutic response in HCC. CONCLUSIONS: Our work demonstrated 3 immune clusters with different features. More importantly, multi-omics signatures, such as MMP9 was identified based on three clusters to help us recognize patients with different prognosis and responses to immunotherapy in HCC. This study could further reveal the immune status of HCC and provide potential predictors for immune checkpoint treatment response.