Overexpression of HDAC6 suppresses tumor cell proliferation and metastasis by inhibition of the canonical Wnt/β-catenin signaling pathway in hepatocellular carcinoma

SIX3 function in cancer: progression and comprehensive analysis

The homeobox gene family encodes transcription factors that are essential for cell growth, proliferation, and differentiation, and its dysfunction is linked to tumor initiation and progression. Sine oculis homeobox (SIX) belongs to the homeobox gene family, with SIX3 being a core member. Recent studies indicate that SXI3 functions as a cancer suppressor or promoter, which is mainly dependent on SIX3's influence on the signal pathways that promote or inhibit cancer in cells. The low expression of SIX3 in most malignant tumors was confirmed by detailed studies, which could promote the cell cycle, proliferation, migration, and angiogenesis. The recovery or upregulation of SIX3 expression to suppress cancer is closely related to the direct or indirect inhibition of the Wnt pathway. However, in some malignancies, such as esophageal cancer and gastric cancer, SIX3 is a tumor-promoting factor, and repressing SIX3 improves patients' prognosis. This review introduces the research progress of SIX3 in tumors and gives a comprehensive analysis, intending to explain why SIX3 plays different roles in different cancers and provide new cancer therapy strategies.

Establishment of DNA Methylation Profile Associated with TCM Syndrome in Endometriosis

Objectives

To screen the potential epigenetic biomarkers associated with endometriosis (EMS) and traditional Chinese medicine (TCM) syndrome EMS types.

Methods

A cohort of 99 participants comprising 42 EMS patients with cold coagulation blood stasis (CCBS) syndrome, 35 EMS patients with Qi stagnation blood stasis (QSBS) syndrome, and 22 women of childbearing age without EMS were recruited. Reduced representation bisulfite sequencing (RRBS) was used to establish the differential DNA methylation profiles in human peripheral blood samples obtained from four non-EMS and four EMS patients with CCBS or QSBS syndrome, respectively. Differentially expressed genes (DEGs) were verified in 18 non-EMS, 38 CCBS-EMS, and 31 QSBS-EMS using pyrosequencing.

Results

Methylation sites of 123942, 127229, and 115961 were found in peripheral blood DNA of non-EMS, CCBS-EMS, and QSBS-EMS patients, respectively. GO and KEGG analyses showed that the pathological process of EMS may be closely related to the nervous system development, cell junctions, GABA-gated chloride ion channel activity, nicotine addiction, Hippo signaling pathway, mRNA surveillance pathway, and Wnt signaling pathway. The methylation level at CpG site within HDAC6 gene in QSBS-EMS patients was significantly different from that in control women.

Conclusions

The changes in DNA methylation in peripheral blood samples may be associated with EMS and TCM syndrome EMS types. The methylation level of HDAC6 gene may be used to distinguish QSBS-EMS patients from women without EMS.

Wnt/β-Catenin Signaling as a Driver of Hepatocellular Carcinoma Progression: An Emphasis on Molecular Pathways

Liver cancers cause a high rate of death worldwide and hepatocellular carcinoma (HCC) is considered as the most common primary liver cancer. HCC remains a challenging disease to treat. Wnt/β-catenin signaling pathway is considered a tumor-promoting factor in various cancers; hence, the present review focused on the role of Wnt signaling in HCC, and its association with progression and therapy response based on pre-clinical and clinical evidence. The nuclear translocation of β-catenin enhances expression level of genes such as c-Myc and MMPs in increasing cancer progression. The mutation of CTNNB1 gene encoding β-catenin and its overexpression can lead to HCC progression. β-catenin signaling enhances cancer stem cell features of HCC and promotes their growth rate. Furthermore, β-catenin prevents apoptosis in HCC cells and increases their migration via triggering EMT and upregulating MMP levels. It is suggested that β-catenin signaling participates in mediating drug resistance and immuno-resistance in HCC. Upstream mediators including ncRNAs can regulate β-catenin signaling in HCC. Anti-cancer agents inhibit β-catenin signaling and mediate its proteasomal degradation in HCC therapy. Furthermore, clinical studies have revealed the role of β-catenin and its gene mutation (CTNBB1) in HCC progression. Based on these subjects, future experiments can focus on developing novel therapeutics targeting Wnt/β-catenin signaling in HCC therapy.

Aggresome-Autophagy Associated Gene HDAC6 Is a Potential Biomarker in Pan-Cancer, Especially in Colon Adenocarcinoma

BACKGROUND

Histone deacetylase 6 (HDAC6) regulates cytoplasmic signaling networks through the deacetylation of various cytoplasmic substrates. Recent studies have identified the role of HDAC6 in tumor development and immune metabolism, but its specific function remains unclear.

METHODS

The current study determined the role of HDAC6 in tumor metabolism and tumor immunity through a multi-database pan-cancer analysis. The Cancer Genome Atlas (TCGA), Genotype-Tissue Expression (GTEx), and Cancer Cell Line Encyclopedia (CCLE) datasets were used to determine the expression levels, prognosis, tumor progression, immune checkpoints, and immune metabolism of HDAC6 in 33 tumors. Pathways, immune checkpoints, immune neoantigens, immune microenvironment, tumor mutational burden (TMB), microsatellite instability (MSI), DNA mismatch repair (MMR), and the value of methyltransferases. The R package was used for quantitative analysis and panoramic description.

RESULTS

In the present study, we determined that HDAC6 is differentially expressed in pan carcinomas, and by survival, we found that HDAC6 was generally associated with the prognosis of pancreatic adenocarcinoma, Thymoma, and uveal melanoma, where low expression of HDAC6 had a significantly worse prognosis. Secondly, through this experiment, we confirmed that HDAC6 expression level was associated with tumor immune infiltration and tumor microenvironment, especially in PAAD. Finally, HDAC6 was associated with immune neoantigen and immune checkpoint gene expression profiles in all cancers in addition to TMB and MSI in pan-cancers.

CONCLUSION

HDAC6 is differentially expressed in pan-cancers and plays an essential role in tumor metabolism and immunity. HDAC6 holds promise as a tumor potential prognostic marker, especially in colon cancer.

Alcohol-induced Hsp90 acetylation is a novel driver of liver sinusoidal endothelial dysfunction and alcohol-related liver disease

BACKGROUND & AIMS

Liver sinusoidal endothelial cell (LSEC) dysfunction has been reported in alcohol-related liver disease, yet it is not known whether LSECs metabolize alcohol. Thus, we investigated this, as well as the mechanisms of alcohol-induced LSEC dysfunction and a potential therapeutic approach for alcohol-induced liver injury.

METHODS

Primary human, rat and mouse LSECs were used. Histone deacetylase 6 (HDAC6) was overexpressed specifically in liver ECs via adeno-associated virus (AAV)-mediated gene delivery to decrease heat shock protein 90 (Hsp90) acetylation in ethanol-fed mice.

RESULTS

LSECs expressed CYP2E1 and alcohol dehydrogenase 1 (ADH1) and metabolized alcohol. Ethanol induced CYP2E1 in LSECs, but not ADH1. Alcohol metabolism by CYP2E1 increased Hsp90 acetylation and decreased its interaction with endothelial nitric oxide synthase (eNOS) leading to a decrease in nitric oxide (NO) production. A non-acetylation mutant of Hsp90 increased its interaction with eNOS and NO production, whereas a hyperacetylation mutant decreased NO production. These results indicate that Hsp90 acetylation is responsible for decreases in its interaction with eNOS and eNOS-derived NO production. AAV8-driven HDAC6 overexpression specifically in liver ECs deacetylated Hsp90, restored Hsp90's interaction with eNOS and ameliorated alcohol-induced liver injury in mice.

CONCLUSION

Restoring LSEC function is important for ameliorating alcohol-induced liver injury. To this end, blocking acetylation of Hsp90 specifically in LSECs via AAV-mediated gene delivery has the potential to be a new therapeutic strategy.

LAY SUMMARY

Alcohol metabolism in liver sinusoidal endothelial cells (LSECs) and the mechanism of alcohol-induced LSEC dysfunction are largely unknown. Herein, we demonstrate that LSECs can metabolize alcohol. We also uncover a mechanism by which alcohol induces LSEC dysfunction and liver injury, and we identify a potential therapeutic strategy to prevent this.

TRIM27 acts as an oncogene and regulates cell proliferation and metastasis in non-small cell lung cancer through SIX3-β-catenin signaling

The Wnt/β-catenin pathway plays vital roles in diverse biological processes, including cell differentiation, proliferation, migration, and insulin sensitivity. A recent study reported that the DNA-binding transcriptional factor SIX3 is essential during embryonic development in vertebrates and capable of downregulating target genes of the Wnt/β-catenin pathway in lung cancer, indicating negative regulation of Wnt/β-catenin activation. However, regulation of the SIX3-Wnt/β-catenin pathway axis remains unknown. We measured the expression of TRIM27 and SIX3 as well as investigated whether there was a correlation between them in lung cancer tissue samples. Herein, we found that the E3 ubiquitin ligase, TRIM27, ubiquitinates, and degrades SIX3. TRIM27 induces non-small cell lung cancer (NSCLC) cell proliferation and metastasis, and the expression of β-catenin, S100P, TGFB3, and MMP-9 were significantly inhibited by SIX3. Furthermore, XAV939 is a selective β-catenin-mediated transcription inhibitor that inhibited TRIM27- and SIX3-mediated NSCLC cell proliferation, migration, and invasion. Clinically, lung tissue samples of cancer patients showed increased TRIM27 expression and decreased SIX3 expression. Taken together, these data demonstrate that TRIM27 acts as an oncogene regulating cell proliferation and metastasis in NSCLC through SIX3-β-catenin signaling.

HDAC6 promotes growth, migration/invasion, and self-renewal of rhabdomyosarcoma

Rhabdomyosarcoma (RMS) is a devastating pediatric sarcoma. The survival outcomes remain poor for patients with relapsed or metastatic disease. Effective targeted therapy is lacking due to our limited knowledge of the underlying cellular and molecular mechanisms leading to disease progression. In this study, we used functional assays in vitro and in vivo (zebrafish and xenograft mouse models) to demonstrate the crucial role of HDAC6, a cytoplasmic histone deacetylase, in driving RMS tumor growth, self-renewal, and migration/invasion. Treatment with HDAC6-selective inhibitors recapitulates the HDAC6 loss-of-function phenotypes. HDAC6 regulates cytoskeletal dynamics to promote tumor cell migration and invasion. RAC1, a Rho family GTPase, is an essential mediator of HDAC6 function, and is necessary and sufficient for RMS cell migration and invasion. High expression of RAC1 correlates with poor clinical prognosis in RMS patients. Targeting the HDAC6-RAC1 axis represents a promising therapeutic option for improving survival outcomes of RMS patients.

OIP5-AS1 contributes to tumorigenesis in hepatocellular carcinoma by miR-300/YY1-activated WNT pathway

Background

It has reported that long non-coding RNAs (lncRNAs) exerted regulatory functions by targeting specific genes through a competing endogenous RNA (ceRNA) pathway. LncRNA OIP5-AS1 has been identified as a tumor-enhancer in several tumor types. Nonetheless, its molecular mechanism in HCC remains to be masked.

Aim of the study

This study was aimed at exploring whether and how OIP5-AS1 exert functions in HCC.

Methods

qRT-PCR and western blot were employed for detecting gene expression. CCK-8, colony formation and EdU assays were implemented to evaluate the proliferative ability of HCC cells. Caspase-3 activity and flow cytometry analyses were implemented to determine cell apoptosis and cell cycle distribution. RNA pull down, ChIP, RIP and luciferase reporter assays explored the interplays between molecules.

Results

YY1 was upregulated in HCC cells, and silenced YY1 restrained HCC cell proliferation in vitro and hampered tumor growth in vivo. Later, we discovered that miR-300 could regulate WNT pathway via targeting YY1. Furthermore, OIP5-AS1 was identified as the sponge of miR-300 and promoted cell growth in HCC. Importantly, YY1 transcriptionally activate OIP5-AS1 in turn. Rescue experiments indicated that miR-300 inhibition or YY1 overexpression abrogated the inhibitive effect of OIP5-AS1 silencing on the malignant growth of HCC cells.

Conclusions

OIP5-AS1/miR-300/YY1 feedback loop facilitates cell growth in HCC by activating WNT pathway.

LncRNA ANCR Suppresses the Progression of Hepatocellular Carcinoma Through the Inhibition of Wnt/β-Catenin Signaling Pathway

Objective

Our study aimed to investigate the effect of anti-differentiation noncoding RNA (ANCR) on hepatocellular carcinoma (HCC) and its potential molecular mechanisms.

Methods

The expression of ANCR was detected by qRT-RCR in both HCC tissues and HCC cells. Moreover, the relationship between ANCR expression and clinical parameters in HCC patients was investigated. The proliferation, cell clones, migration, invasion and apoptosis of MHCC97H and HCCLM3 cells were measured by MTT assay, colony formation assay, transwell assay and flow cytometry, respectively. The expressions of N-cadherin, vimentin, E-cadherin, cleaved caspase-3, Bax, Bcl-2, Wnt1, β-catenin and GSK-3β in MHCC97H and HCCLM3 cells were measured by Western blot.

Results

Our results showed that ANCR was lowly expressed in both HCC tissues and HCC cells. ANCR expression was closely associated with tumor size, tumor-node-metastasis (TNM) stages and vascular invasion in HCC. ANCR could dramatically inhibit cell proliferation, migration and invasion, as well as promote apoptosis in MHCC97H and HCCLM3 cells. ANCR could significantly increase the expression of cleaved caspase-3, Bax, E-cadherin and GSK-3β but reduce the expression of Bcl-2, N-cadherin, vimentin, Wnt1 and β-catenin in MHCC97H and HCCLM3 cells. In addition, Wnt/β-catenin pathway inhibitor (IWP-2) partially reversed the effects of silencing ANCR on the proliferation, migration, invasion and apoptosis of HCCLM3 cells.

Conclusion

Our study demonstrated that ANCR can suppress cell proliferation, migration and invasion, as well as promote apoptosis of HCC cells via modulation of the Wnt/β-catenin signaling pathway.

Wnt/β-Catenin Pathway-Regulated Fibromodulin Expression Is Crucial for Breast Cancer Metastasis and Inhibited by Aspirin

Emerging evidence suggests that fibromodulin (FMOD), an extracellular matrix protein, is associated with cancer, and yet little is known about the regulation of FMOD expression and its role in cancer metastasis. Aspirin, a classic anti-inflammatory drug, has been indicated to offer anticancer benefits, but its action targets and mechanisms remain obscure. In the present study using cell lines, animal model and database analysis, we show that FMOD is crucial for breast cancer cell migration and invasion (BCCMI) via activation of ERK; expression of FMOD is regulated positively by the Wnt/β-catenin pathway, wherein the β-catenin/TCF4/LEF1 complex binds the FMOD promoter to transcribe FMOD. Aspirin inhibits BCCMI by attenuating Wnt/β-catenin signaling and suppressing FMOD expression via inhibiting deacetylation of β-catenin by histone deacetylase 6 (HDAC6) leading to β-catenin phosphorylation and cytoplasmic degradation. Moreover, expression of the transcriptional complex components β-catenin/TCF4/LEF1 is upregulated by the Wnt/β-catenin pathway, constituting positive feedback loops that amplify its signal output. Our findings identify a critical role of FMOD in cancer metastasis, reveal a mechanism regulating FMOD transcription and impacting tumor metastasis, uncover action targets and mechanism for the anticancer activity of Aspirin, and expand the understanding of the Wnt/β-catenin pathway and tumor metastasis, which are valuable for development of cancer therapeutics.

Anti-Invasion and Antimetastatic Effects of Porcine Recombinant NK-lysin on SMMC-7721 Human Hepatocellular Carcinoma Cells

The high invasion and metastasizing abilities of hepatocellular carcinoma (HCC) are the primary reasons for the high mortality rate of patients. Therefore, identification of agents to inhibit invasion and metastasis is very important for treatment of HCC. We analyzed the anti-invasion and antimetastatic effects of porcine recombinant NK-lysin, which was designed and expressed in vitro by our research group, on SMMC-7721 hepatocellular carcinoma cells via wound-healing assays, adhesion assays, invasion assays, real-time polymerase chain reaction (PCR), and Western blot analysis. MTT assay results indicated that NK-lysin inhibited the growth of SMMC-7721 cells in a dose- and time-dependent manner. NK-lysin reduced the ability of cell migration, adhesion, and invasion. Based on gene and protein expression analysis, NK-lysin decreased β-catenin and MMP-2 expression. These results suggested that NK-lysin has anti-invasion and antimetastatic effects on hepatocellular carcinoma cells in vitro by reducing the level of the β-catenin and MMP-2.