Significant association between upstream transcription factor 1 rs2516839 polymorphism and hepatocellular carcinoma risk: a case–control study

USF1 modulates transcription and cellular functions by regulating multiple transcription factors in Huh7 cells

Liver cancer, including hepatocellular carcinoma (HCC), is a malignant tumor that has high rates of metastasis and mortality worldwide. Upstream transcription factor 1 (USF1) is a canonical transcription factor (TF) and is associated with the pathogenesis of several cancers, but its biological functions and molecular targets in HCC remain unclear. Huh7 cells that overexpress USF1 were used with whole transcriptome profiling through RNA sequencing and chromatin immunoprecipitation (ChIP) sequencing methods to investigate the downstream targets of USF1. Reverse transcription-quantitative PCR was then used to validate the downstream targets. The results showed that USF1 significantly regulates 350 differentially expressed genes (DEGs). The upregulated DEGs were primarily protein-coding genes enriched in immune and inflammation response pathways, while the downregulated DEGs were mainly coding long non-coding (lnc)RNAs, indicating the regulatory function of USF1. It was also demonstrated that USF1 directly binds to the promoter region of 2,492 genes, which may be involved in the viral progression and cell proliferation pathways. By integrating these two datasets, 16 overlapped genes were detected, including downregulated lncRNA-NEAT1 and upregulated TF-ETV5. The downregulated lncRNA-NEAT1 showed reverse expression pattern and prognosis result compared with that of USF1 in patients with liver cancer, while upregulated TF-ETV5 showed consistent results with USF1. Promoter region motif analysis indicated that ETV5 has more binding motifs and genes than USF1 itself for USF1-regulated DEGs, indicating that USF1 may indirectly modulate gene expression by regulating ETV5 expression in Huh7 cells. The study also validated the direct interaction between USF1 and the promoter of ETV5 using ChIP-qPCR. In summary, the results demonstrated that USF1 binds to the promoter region of thousands of genes and affects a large part of DEGs indirectly. Downstream genes, including lncRNA-NEAT1 and TF-ETV5, may also have potential functions in the regulated network by USF1 and have potential functions in the progression of HCC. The present findings suggested that USF1 and its downstream targets could be potential targets for HCC therapy in the future.

Silencing RPL8 inhibits the progression of hepatocellular carcinoma by down-regulating the mTORC1 signalling pathway

This study aimed to explore the role of ribosomal protein L8 (RPL8) in controlling hepatocellular carcinoma (LIHC) development. We measured RPL8 expression, apoptosis, cell viability, proliferation, migration, invasion, glucose uptake, lactate production, and the ATP/ADP ratio of LIHC cells to investigate the effect of RPL8 on LIHC. Bioinformatic analysis was employed to analyse RPL8 expression and its potential mechanism in LIHC. RPL8 was upregulated in LIHC tissues and cells. RPL8 silencing accelerated apoptosis and suppressed viability, growth, and movement of LIHC cells. Additionally, RPL8 silencing inhibited glycolysis in LIHC cells. Bioinformatic analysis revealed that RPL8 is regulated by the upstream transcription factor upstream stimulating factor 1 (USF1) and activates the mTORC1 signalling pathway. USF1 overexpression eliminated the inhibitory effect of RPL8 silencing in LIHC cells. RPL8 overexpression increased cell growth, movement, and glycolysis in LIHC. However, inhibition of the mTORC1 signalling pathway eliminated the effect of RPL8 overexpression on LIHC cells. In conclusion, RPL8 may affect LIHC progression by regulating the mTORC1 signalling pathway.

USF1 defect drives p53 degradation during Helicobacter pylori infection and accelerates gastric carcinogenesis

OBJECTIVE

Helicobacter pylori (Hp) is a major risk factor for gastric cancer (GC). Hp promotes DNA damage and proteasomal degradation of p53, the guardian of genome stability. Hp reduces the expression of the transcription factor USF1 shown to stabilise p53 in response to genotoxic stress. We investigated whether Hp-mediated USF1 deregulation impacts p53-response and consequently genetic instability. We also explored in vivo the role of USF1 in gastric carcinogenesis.

DESIGN

Human gastric epithelial cell lines were infected with Hp7.13, exposed or not to a DNA-damaging agent camptothecin (CPT), to mimic a genetic instability context. We quantified the expression of USF1, p53 and their target genes, we determined their subcellular localisation by immunofluorescence and examined USF1/p53 interaction. Usf1^-/- and INS-GAS mice were used to strengthen the findings in vivo and patient data examined for clinical relevance.

RESULTS

In vivo we revealed the dominant role of USF1 in protecting gastric cells against Hp-induced carcinogenesis and its impact on p53 levels. In vitro, Hp delocalises USF1 into foci close to cell membranes. Hp prevents USF1/p53 nuclear built up and relocates these complexes in the cytoplasm, thereby impairing their transcriptional function. Hp also inhibits CPT-induced USF1/p53 nuclear complexes, exacerbating CPT-dependent DNA damaging effects.

CONCLUSION

Our data reveal that the depletion of USF1 and its de-localisation in the vicinity of cell membranes are essential events associated to the genotoxic activity of Hp infection, thus promoting gastric carcinogenesis. These findings are also of clinical relevance, supporting USF1 expression as a potential marker of GC susceptibility.

Roles of chitinase 3-like 1 in the development of cancer, neurodegenerative diseases, and inflammatory diseases

Chitinase 3-like 1 (CHI3L1) is a secreted glycoprotein that mediates inflammation, macrophage polarization, apoptosis, and carcinogenesis. The expression of CHI3L1 is strongly increased by various inflammatory and immunological conditions, including rheumatoid arthritis, multiple sclerosis, Alzheimer's disease, and several cancers. However, its physiological and pathophysiological roles in the development of cancer and neurodegenerative and inflammatory diseases remain unclear. Several studies have reported that CHI3L1 promotes cancer proliferation, inflammatory cytokine production, and microglial activation, and that multiple receptors, such as advanced glycation end product, syndecan-1/αVβ3, and IL-13Rα2, are involved. In addition, the pro-inflammatory action of CHI3L1 may be mediated via the protein kinase B and phosphoinositide-3 signaling pathways and responses to various pro-inflammatory cytokines, including tumor necrosis factor-α, interleukin-1β, interleukin-6, and interferon-γ. Therefore, CHI3L1 could contribute to a vast array of inflammatory diseases. In this article, we review recent findings regarding the roles of CHI3L1 and suggest therapeutic approaches targeting CHI3L1 in the development of cancers, neurodegenerative diseases, and inflammatory diseases.

Decreased Lung Tumor Development in SwAPP Mice through the Downregulation of CHI3L1 and STAT 3 Activity via the Upregulation of miRNA342-3p

We previously found that lung tumor development was reduced in a presenilin (PS) Alzheimer’s disease (AD) mouse model. Here, we investigated whether this reducing effect could occur in a different AD mouse model. We investigated urethane-induced (1 mg/g) lung tumor development and melanoma growth in Swedish amyloid precursor protein (SwAPP) transgenic mice. The expression of chitinase-3-like-1 (Chi3L1) increased during lung tumor development and melanoma growth, which was accompanied by an increase in the activity of signal transducer and activator of transcription 3 (STAT3) and the downregulation of miRNA342-3p in wild-type mice. Like tumor development, the expression of Chi3L1 and STAT3 activity was reduced in the SwAPP mice, whereas the expression of miRNA342-3p was upregulated. In addition, Chi3L1 knockdown in the lung cancer and melanoma tissues reduced cancer cell growth and STAT3 activity but enhanced miRNA342-3p expression. However, the miRNA342-3p mimic decreased Chi3L1 expression, cancer cell growth, and STAT3 activity. Moreover, a STAT3 inhibitor reduced Chi3L1 expression and cancer cell growth but enhanced miRNA342-3p expression. These data showed that lung tumor development was reduced through the decrease of Chi3L1 expression via the STAT3-dependent upregulation of miRNA342-3p. This study indicates that lung tumor development could be reduced in SwAPP AD mice.

Suppression of metastasis through inhibition of chitinase 3-like 1 expression by miR-125a-3p-mediated up-regulation of USF1

Rationale: Chitinase 3-like 1 (Chi3L1) protein is up-regulated in various diseases including solid cancers. According to Genome-Wide Association Study (GWAS)/Online Mendelian Inheritance in Man (OMIM)/Differentially Expressed Gene (DEG) analyses, Chi3L1 is associated with 38 cancers, and more highly associated with cancer compared to other oncogenes such as EGFR, TNFα, etc. However, the mechanisms and pathways by which Chi3L1 is associated with cancer are not clear. In current study, we investigated the role of Chi3L1 in lung metastasis. Methods: We performed the differentially expressed gene analysis to explore the genes which are associated with Chi3L1 using the web-based platform from Biomart. We investigated the metastases in lung tissues of C57BL/6 mice injected with B16F10 melanoma following treatment with Ad-shChi3L1. We also investigated the expression of USF1 and Chi3L1 in Chi3L1 KD mice lung tissues by Western blotting and IHC. We also analyzed lung cancer cells metastases induced by Chi3L1 using migration and cell proliferation assay in human lung cancer cell lines. The involvement of miR-125a-3p in Chi3L1 regulation was determined by miRNA qPCR and luciferase reporter assay. Results: We showed that melanoma metastasis in lung tissues was significantly reduced in Chi3L1 knock-down mice, accompanied by down-regulation of MMP-9, MMP-13, VEGF, and PCNA in Chi3L1 knock-down mice lung tissue, as well as in human lung cancer cell lines. We also found that USF1 was conversely expressed against Chi3L1. USF1 was increased by knock-down of Chi3L1 in mice lung tissues, as well as in human lung cancer cell lines. In addition, knock-down of USF1 increased Chi3L1 levels in addition to augmenting metastasis cell migration and proliferation in mice model, as well as in human cancer cell lines. Moreover, in human lung tumor tissues, the expression of Chi3L1 was increased but USF1 was decreased in a stage-dependent manner. Finally, Chi3L1 expression was strongly regulated by the indirect translational suppressing activity of USF1 through induction of miR-125a-3p, a target of Chi3L1. Conclusion: Metastases in mice lung tissues and human lung cancer cell lines were decreased by KD of Chi3L1. USF1 bound to the Chi3L1 promoter, however, Chi3L1 expression was decreased by USF1, despite USF1 enhancing the transcriptional activity of Chi3L1. We found that USF1 induced miR-125a-3p levels which suppressed Chi3L1 expression. Ultimately, our results suggest that lung metastasis is suppressed by knock-down of Chi3L1 through miR-125a-3p-mediated up-regulation of USF1.

Long noncoding RNA AWPPH promotes hepatocellular carcinoma progression through YBX1 and serves as a prognostic biomarker

Long noncoding RNAs (lncRNAs) have been shown to play important roles in various cancers. However, the clinical significances and biological roles of lncRNAs in hepatocellular carcinoma (HCC) remain largely unknown. In this study, using online-available data sets and quantitative real-time PCR, we identified a novel lncRNA termed lncRNA-AWPPH, which is highly expressed in HCC tissues. Its upregulation is correlated with encapsulation incomplete, microvascular invasion, advanced TNM stage and BCLC stage. Cox proportional hazards regression analysis revealed that high lncRNA-AWPPH expression is an independent prognostic factor for poor recurrence-free and overall survival. Functional experiments showed that overexpression of lncRNA-AWPPH promotes HCC cell proliferation and migration in vitro, and tumor growth and metastasis in vivo. Conversely, depletion of lncRNA-AWPPH has opposite effects on HCC. Mechanistically, lncRNA-AWPPH interacts with YBX1, promotes YBX1-mediated activation of SNAIL1 translation, and upregulates SNAIL1 expression. Furthermore, lncRNA-AWPPH promotes YBX1-mediated activation of PIK3CA transcription, upregulates PIK3CA expression, and activates PI3K/AKT pathway. Depletion of YBX1 abolishes the effects of lncRNA-AWPPH on SNAIL1 and PIK3CA, and also the biological roles of lncRNA-AWPPH on HCC cells. In conclusion, this study identifies a novel lncRNA termed lncRNA-AWPPH which is highly expressed in HCC, indicates poor prognosis of HCC patients, and promotes HCC cell proliferation, migration, and in vivo tumor growth and metastasis via a novel regulatory mechanism of interacting with YBX1.

Mannose-binding lectin 2 rs11003123 polymorphism is associated with the development of hepatocellular carcinoma in patients with hepatitis B-related cirrhosis in the Chinese population

BACKGROUND

Mannose-binding lectin 2 (MBL2) plays a key role in the host immune response, but whether it is associated with hepatocellular carcinoma (HCC) is not clear. The present study aimed to identify the association between MBL2 gene polymorphisms and HCC in patients with hepatitis B virus (HBV)-related cirrhosis in the Chinese population.

METHODS

A single-nucleotide polymorphism of MBL2, rs11003123, was genotyped and analyzed in a case-control study of HBV-related cirrhotic patients with HCC (n=77) and without HCC (n=40).

RESULTS

We found that Child-Pugh profiles, model for end-stage liver disease score, and the incidence of encephalopathy were all higher in the non-HCC group (P<0.05). A significant association between allele mutants and HCC occurrence was demonstrated by allele comparison (A vs G) (OR=0.34; 95% CI: 0.15-0.76; P=0.006). Heterozygous comparison (GA vs GG) revealed that the individuals with GA mutants had a reduced risk of HCC occurrence compared with those with GG wild type (adjusted OR=0.28; 95% CI: 0.10-0.80; P=0.004). In a dominant model (GA+AA vs GG), a decreased risk of HCC occurrence was observed in individuals with variant genotypes (GA and AA) compared with those with the wild type (adjusted OR=0.30; 95% CI: 0.11-0.85; P=0.004). However, no statistically significant associations were observed between rs11003123 and prognosis of patients with HCC after liver transplantation in both recurrence-free survival and overall survival (P=0.449 and P=0.384, respectively).

CONCLUSION

MBL2 rs11003123 polymorphism may be a marker for the risk of HCC occurrence in patients with HBV-related cirrhosis in the Chinese population.