Serine protease inhibitor Kazal type 1 (SPINK1) downregulates E-cadherin and induces EMT of hepatoma cells to promote hepatocellular carcinoma metastasis via the MEK/ERK signaling pathway

Putative epithelial-mesenchymal transitions during salamander limb regeneration: Current perspectives and future investigations

Previous studies have implicated epithelial-mesenchymal transition (EMT) in salamander limb regeneration. In this review, we describe putative roles for EMT during each stage of limb regeneration in axolotls and other salamanders. We hypothesize that EMT and EMT-like gene expression programs may regulate three main cellular processes during limb regeneration: (1) keratinocyte migration during wound closure; (2) transient invasion of the stump by epithelial cells undergoing EMT; and (3) use of EMT-like programs by non-epithelial blastemal progenitor cells to escape the confines of their niches. Finally, we propose nontraditional roles for EMT during limb regeneration that warrant further investigation, including alternative EMT regulators, stem cell activation, and fibrosis induced by aberrant EMT.

High expression of serine protease inhibitor kazal type 1 predicts poor prognosis and promotes the progression and invasion of oral tongue squamous cell carcinoma

OBJECTIVE

This study aimed to investigate the expression of serine protease inhibitor kazal type 1 (SPINK1) and its carcinogenic effect in oral tongue squamous cell carcinoma (OTSCC).

DESIGN

Initially, bioinformatics analysis was conducted using data from The Cancer Genome Atlas and Gene Expression Omnibus to compare SPINK1 mRNA expression between malignant and adjacent tissues. Subsequently, the impact of differential expression on survival and other clinical variables was examined. Additionally, histology microarray analysis was performed to assess SPINK1 protein expression in 35 cases of malignant and adjacent tissues. Finally, alterations in SPINK1 expression were evaluated to determine its biological phenotypes in OTSCC, including proliferation, apoptosis, invasion, and metastasis.

RESULTS

OTSCC tissues exhibit higher levels of SPINK1 compared to surrounding cancerous tissues. Notably, increased SPINK1 expression correlates with the pathological N stage and independently predicts overall survival among patients with OTSCC.

CONCLUSION

Suppression of SPINK1 inhibited OTSCC cell proliferation, invasion, and motility while promoting apoptosis. These findings suggest that SPINK1 may serve as a prognostic biomarker as well as a potential therapeutic target for managing OTSCC.

Serine protease inhibitor Kazal type 1 (SPINK1) promotes proliferation, migration, invasion and radiation resistance in rectal cancer patients receiving concurrent chemoradiotherapy: a potential target for precision medicine

Serine peptidase inhibitor Kazal type-1 (SPINK1), a trypsin kinase inhibitor, is known to be associated with inflammation and pathogenesis. The aim in this study was to demonstrate the clinicopathological role and progression of SPINK1 in rectal cancer (RC) patients undergoing concurrent chemoradiotherapy (CCRT). Immunohistochemical staining for SPINK1 protein expression in 111 RC cases revealed high SPINK1 expression was significantly associated with perineural invasion and poor CCRT response in pre-CCRT specimens. In addition, multivariable analyses showed that pre-CCRT SPINK1 expression was a significant prognostic marker of both overall and disease-free survival in RC patients receiving pre-operative CCRT; furthermore, in vitro studies demonstrated SPINK1 interacted with EGFR to promote the abilities of proliferation, migration and invasion attenuated by SPINK1 si-RNA via ERK, p38, and JNK pathways. SPINK1 was also found to regulate radio-resistance in CRC cell lines. In conclusion, SPINK1 expression is an independent prognostic marker in patients receiving pre-operative CCRT, and SPINK1 regulates proliferation, migration and invasion via EGFR-downstream ERK, p38 and JNK pathways. The phenotypes of radiosensitivity that could be reversed with attenuation of SPINK1 levels suggest that targeting SPINK1 might offer a strategy for optimal precision medicine.

A novel diagnostic four-gene signature for hepatocellular carcinoma based on artificial neural network: Development, validation, and drug screening

Background: Hepatocellular carcinoma (HCC) is one of the most common cancers with high mortality in the world. HCC screening and diagnostic models are becoming effective strategies to reduce mortality and improve the overall survival (OS) of patients. Here, we expected to establish an effective novel diagnostic model based on new genes and explore potential drugs for HCC therapy.

Methods: The gene expression data of HCC and normal samples (GSE14811, GSE60502, GSE84402, GSE101685, GSE102079, GSE113996, and GSE45436) were downloaded from the Gene Expression Omnibus (GEO) dataset. Bioinformatics analysis was performed to distinguish two differentially expressed genes (DEGs), diagnostic candidate genes, and functional enrichment pathways. QRT-PCR was used to validate the expression of diagnostic candidate genes. A diagnostic model based on candidate genes was established by an artificial neural network (ANN). Drug sensitivity analysis was used to explore potential drugs for HCC. CCK-8 assay was used to detect the viability of HepG2 under various presentative chemotherapy drugs.

Results: There were 82 DEGs in cancer tissues compared to normal tissue. Protein–protein interaction (PPI), Gene Ontology (GO), and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses and infiltrating immune cell analysis were administered and analyzed. Diagnostic-related genes of MT1M, SPINK1, AKR1B10, and SLCO1B3 were selected from DEGs and used to construct a diagnostic model. The receiver operating characteristic (ROC) curves were 0.910 and 0.953 in the training and testing cohorts, respectively. Potential drugs, including vemurafenib, LOXO-101, dabrafenib, selumetinib, Arry-162, and NMS-E628, were found as well. Vemurafenib, dabrafenib, and selumetinib were observed to significantly affect HepG2 cell viability.

Conclusion: The diagnostic model based on the four diagnostic-related genes by the ANN could provide predictive significance for diagnosis of HCC patients, which would be worthy of clinical application. Also, potential chemotherapy drugs might be effective for HCC therapy.

Critical Investigation of the Usability of Hepatoma Cell Lines HepG2 and Huh7 as Models for the Metabolic Representation of Resectable Hepatocellular Carcinoma

Metabolic alterations in hepatocellular carcinoma (HCC) are fundamental for the development of diagnostic screening and therapeutic intervention since energy metabolism plays a central role in differentiated hepatocytes. In HCC research, hepatoma cell lines (HCLs) like HepG2 and Huh7 cells are still the gold standard. In this study, we characterized the metabolic profiles of primary human hepatoma cells (PHCs), HCLs and primary human hepatocytes (PHHs) to determine their differentiation states. PHCs and PHHs (HCC-PHHs) were isolated from surgical specimens of HCC patients and their energy metabolism was compared to PHHs from non-HCC patients and the HepG2 and Huh7 cells at different levels (transcript, protein, function). Our analyses showed successful isolation of PHCs with a purity of 50–73% (CK18+). The transcript data revealed that changes in mRNA expression levels had already occurred in HCC-PHHs. While many genes were overexpressed in PHCs and HCC-PHHs, the changes were mostly not translated to the protein level. Downregulated metabolic key players of PHCs revealed a correlation with malign transformation and were predominantly pronounced in multilocular HCC. Therefore, HCLs failed to reflect these expression patterns of PHCs at the transcript and protein levels. The metabolic characteristics of PHCs are closer to those of HCC-PHHs than to HCLs. This should be taken into account for future optimized tumor metabolism research.

Bombyx batryticatus Cocoonase Inhibitor Separation, Purification, and Inhibitory Effect on the Proliferation of SMCC-7721 HeLa-Derived Cells

The present study was to isolate and purify Bombyx batryticatus cocoonase inhibitor (BBCI) and to evaluate its inhibitory effect on the proliferation of SMCC-7721 cells. BBCI was purified from the crude proteins of Bombyx batryticatus using affinity chromatography with cocoonase as the ligand, its N-terminal amino acid sequence was determined using the Edman degradation method, and its inhibiting activity on SMCC-7721 cell proliferation was detected in vitro using the MTT method and in vivo in tumor-bearing nude mice. The purified BBCI presented as a single band in SDS-PAGE, the molecular weight determined by time-of-flight mass spectrometry was 13,973.63 Da, and its N-terminal amino acid sequence was VRNKRQSNDD. BBCI was a noncompetitive cocoonase inhibitor with an average Michaelis constant of 76.50, and it inhibited cocoonase activity with an inhibition ratio of 1 : 1 (molar). BBCI could inhibit the proliferation of SMCC-7721 cells in vitro with the IC₅₀ being about 260.52 μg/ml within 36 h of treatment and inhibit the SMCC-7721 tumor growth in nude mice by subcutaneous injection of BBCI around the tumor, where the tumor inhibitory effect was dose dependent. BBCI did not significantly influence the spleen coefficient of the mice. In conclusion, to the best of our knowledge, the present study is the first to report that BBCI, which was purified from Bombyx batryticatus, was a serine proteinase inhibitor with antitumor activity.

Clotrimazole Inhibits HCC Migration and Invasion by Modulating the ERK-p65 Signaling Pathway

Purpose

Hepatocellular carcinoma (HCC), has a very high mortality rate and is the most common type of liver cancer. Clotrimazole, a traditional antifungal drug, has garnered considerable attention as a therapeutic strategy for HCC. However, its effects against the migration and invasion of HCC cells as well as the associated underlying mechanisms remain unclear. Therefore, in this study, we investigated its effects on HCC and attempted to elucidate the underlying molecular mechanisms.

Methods

CCK-8 was used to investigate the inhibitory effect of clotrimazole on the proliferation of different types of HCC cells, and wound healing and transwell assays were performed to investigate its inhibitory effect on the invasion and migration of the HCC cells. Further, western blotting was employed to detect changes in the expression levels of epithelial mesenchymal transition (EMT)-related proteins, extracellular-regulated protein kinases (ERK), p-ERK, p65, and p-p65. We also used ERK activators in combination with clotrimazole to treat the HCC cell lines.

Results

Clotrimazole inhibited the invasion and migration of HCC cells, and mechanistically, it exerted these anti-tumor effects via EMT by repressing ERK phosphorylation.

Conclusion

These findings suggest that clotrimazole inhibits HCC metastasis by repressing EMT in an ERK dephosphorylation-dependent manner.

SPINKs in Tumors: Potential Therapeutic Targets

The serine protease inhibitor Kazal type (SPINK) family includes SPINK1-14 and is the largest branch in the serine protease inhibitor family. SPINKs play an important role in pancreatic physiology and disease, sperm maturation and capacitation, Nager syndrome, inflammation and the skin barrier. Evidence shows that the unregulated expression of SPINK1, 2, 4, 5, 6, 7, and 13 is closely related to human tumors. Different SPINKs exhibit various regulatory modes in different tumors and can be used as tumor prognostic markers. This article reviews the role of SPINK1, 2, 4, 5, 6, 7, and 13 in different human cancer processes and helps to identify new cancer treatment targets.

Integrative Analysis of Epigenome and Transcriptome Data Reveals Aberrantly Methylated Promoters and Enhancers in Hepatocellular Carcinoma

DNA methylation is a key transcription regulator, whose aberration was ubiquitous and important in most cancers including hepatocellular carcinoma (HCC). Whole-genome bisulfite sequencing (WGBS) was conducted for comparison of DNA methylation in tumor and adjacent tissues from 33 HCC patients, accompanying RNA-seq to determine differentially methylated region-associated, differentially expressed genes (DMR-DEGs), which were independently replicated in the TCGA-LIHC cohort and experimentally validated via 5-aza-2-deoxycytidine (5-azadC) demethylation. A total of 9,867,700 CpG sites showed significantly differential methylation in HCC. Integrations of mRNA-seq, histone ChIP-seq, and WGBS data identified 611 high-confidence DMR-DEGs. Enrichment analysis demonstrated activation of multiple molecular pathways related to cell cycle and DNA repair, accompanying repression of several critical metabolism pathways such as tyrosine and monocarboxylic acid metabolism. In TCGA-LIHC, we replicated about 53% of identified DMR-DEGs and highlighted the prognostic significance of combinations of methylation and expression of nine DMR-DEGs, which were more efficient prognostic biomarkers than considering either type of data alone. Finally, we validated 22/23 (95.7%) DMR-DEGs in 5-azadC-treated LO2 and/or HepG2 cells. In conclusion, integration of epigenome and transcriptome data depicted activation of multiple pivotal cell cycle-related pathways and repression of several metabolic pathways triggered by aberrant DNA methylation of promoters and enhancers in HCC.

SPINK1 as a plasma marker for tumor hypoxia and a therapeutic target for radiosensitization

Hypoxia is associated with tumor radioresistance; therefore, a predictive marker for tumor hypoxia and a rational target to overcome it have been sought to realize personalized radiotherapy. Here, we show that serine protease inhibitor Kazal type I (SPINK1) meets these 2 criteria. SPINK1 expression was induced upon hypoxia (O2 < 0.1%) at the transcription initiation level in a HIF-dependent manner, causing an increase in secreted SPINK1 levels. SPINK1 proteins were detected both within and around hypoxic regions of xenografted and clinical tumor tissues, and their plasma levels increased in response to decreased oxygen supply to xenografts. Secreted SPINK1 proteins enhanced radioresistance of cancer cells even under normoxic conditions in EGFR-dependent and nuclear factor erythroid 2-related factor 2-dependent (Nrf2-dependent) manners and accelerated tumor growth after radiotherapy. An anti-SPINK1 neutralizing antibody exhibited a radiosensitizing effect. These results suggest that SPINK1 secreted from hypoxic cells protects the surrounding and relatively oxygenated cancer cells from radiation in a paracrine manner, justifying the use of SPINK1 as a target for radiosensitization and a plasma marker for predicting tumor hypoxia.

circRPS16 Promotes Proliferation and Invasion of Hepatocellular Carcinoma by Sponging miR-876-5p to Upregulate SPINK1

The roles of serine protease inhibitor Kazal type 1 (SPINK1) in multiple types of cancers have been significantly documented. However, its specific roles in hepatocellular carcinoma (HCC) remain to be investigated. This study found that SPINK1 is upregulated in HCC and its upregulation correlates with poor prognosis. Besides, functional assays revealed that SPINK1 promotes cell proliferation, cell cycle, and invasion in vitro. Through bioinformatics analysis, we speculate that circRPS16 regulates SPINK1 expression by sponging miR-876-5p. This was further verified by the dual-luciferase reporter and fluorescent in situ hybridization (FISH) assays. Subsequently, rescue assays verified that circRPS16 promotes cell proliferation, cell cycle, and invasion through miR-876-5p. Importantly, silencing circRPS16 inhibited tumor growth by downregulating SPINK1 expression in vivo. Collectively, our results confirm that SPINK1 is a downstream target of circRPS16. Besides, circRPS16 and SPINK1 are oncogenic factors in HCC progression; they provide novel diagnostic and therapeutic targets for HCC patients.

Functional Roles of SPINK1 in Cancers

Serine Peptidase Inhibitor Kazal Type 1 (SPINK1) is a secreted protein known as a protease inhibitor of trypsin in the pancreas. However, emerging evidence shows its function in promoting cancer progression in various types of cancer. SPINK1 modulated tumor malignancies and induced the activation of the downstream signaling of epidermal growth factor receptor (EGFR) in cancer cells, due to the structural similarity with epidermal growth factor (EGF). The discoverable SPINK1 somatic mutations, expressional signatures, and prognostic significances in various types of cancer have attracted attention as a cancer biomarker in clinical applications. Emerging findings further clarify the direct and indirect biological effects of SPINK1 in regulating cancer proliferation, metastasis, drug resistance, transdifferentiation, and cancer stemness, warranting the exploration of the SPINK1-mediated molecular mechanism to identify a therapeutic strategy. In this review article, we first integrate the transcriptomic data of different types of cancer with clinical information and recent findings of SPINK1-mediated malignant phenotypes. In addition, a comprehensive summary of SPINK1 expression in a pan-cancer panel and individual cell types of specific organs at the single-cell level is presented to indicate the potential sites of tumorigenesis, which has not yet been reported. This review aims to shed light on the roles of SPINK1 in cancer and provide guidance and potential directions for scientists in this field.

High SPINK1 Expression Predicts Poor Prognosis and Promotes Cell Proliferation and Metastasis of Hepatocellular Carcinoma

BACKGROUND

Serine protease inhibitor Kazal type I (SPINK1) is highly expressed and promotes tumor progress in different cancers. This study aimed to evaluate SPINK1's prognostic value and its role in hepatocellular carcinoma (HCC) progress.

METHODS

We use tissue micro-arrays containing 273 tumor and paired para-tumor tissues to evaluate SPINK1's prognostic value in HCC. CCK8 cell proliferation assay, wound healing assays, transwell migration and invasion assays were performed to explore the effect of SPINIK1 on HCC cells. The Cancer Genome Atlas (TCGA) database and Gene set enrichment analysis (GSEA) were used to verify the prognosis value of SPINK1 in HCC and explore the underlying mechanisms.

RESULTS

SPINK1 expression was significantly higher in tumor tissues than paired para-tumor tissues (P < 0.001). Higher SPINK1 expression in tumor was significantly associated with portal vein tumor thrombus formation (P = 0.019) and shorter overall survival (P = 0.029). SPINK1 expression in tumor tissue was an independent predictor for overall survival. SPINK1 increased proliferation (P < 0.001), enhanced migration and invasion ability of HCC cell lines (P < 0.001). GSEA revealed that glycine, serine, threonine and bile acid metabolism may be the underlying mechanism of SPINK1 in HCC.

CONCLUSIONS

In conclusion, high SPINK1 expression is associated with poor prognosis of HCC. SPINK1 promotes proliferation, migration and invasion ability of HCC cells.

RAC1B: A Guardian of the Epithelial Phenotype and Protector Against Epithelial-Mesenchymal Transition

The small GTPase Ras-related C3 botulinum toxin substrate 1B (RAC1B) has been shown to potently inhibit transforming growth factor (TGF)-β1-induced cell migration and epithelial-mesenchymal transition (EMT) in pancreatic and breast epithelial cells, but the underlying mechanism has remained obscure. Using a panel of pancreatic ductal adenocarcinoma (PDAC)-derived cell lines of different differentiation stages, we show that RAC1B is more abundantly expressed in well differentiated as opposed to poorly differentiated cells. Interestingly, RNA interference-mediated knockdown of RAC1B decreased expression of the epithelial marker protein E-cadherin, encoded by CDH1, and enhanced its TGF-β1-induced downregulation, whereas ectopic overexpression of RAC1B upregulated CDH1 expression and largely prevented its TGF-β1-induced silencing of CDH1. Conversely, knockdown of RAC1B, or deletion of the RAC1B-specific exon 3b by CRISPR/Cas-mediated genomic editing, enhanced basal and TGF-β1-induced upregulation of mesenchymal markers like Vimentin, and EMT-associated transcription factors such as SNAIL and SLUG. Moreover, we demonstrate that knockout of RAC1B enhanced the cells’ migratory activity and derepressed TGF-β1-induced activation of the mitogen-activated protein kinase ERK2. Pharmacological inhibition of ERK1/2 activation in RAC1B-depleted cells rescued cells from the RAC1B knockdown-induced enhancement of cell migration, TGF-β1-induced downregulation of CDH1, and upregulation of SNAI1. We conclude that RAC1B promotes epithelial gene expression and suppresses mesenchymal gene expression by interfering with TGF-β1-induced MEK-ERK signaling, thereby protecting cells from undergoing EMT and EMT-associated responses like acquisition of cell motility.

SPINK1 is a prognosis predicting factor of non-small cell lung cancer and regulates redox homeostasis

Serine protease inhibitor Kazal-type 1 (SPINK1) is a trypsin kinase inhibitor, which is involved in the development of inflammation, cell proliferation and cancer development and progression. However, the prognostic value of SPINK1 in non-small cell lung cancer (NSCLC) and its ability to regulate intrinsic redox homeostasis have, to the best of our knowledge, not been previously investigated. In the present study, it was revealed that SPINK1 is highly expressed in NSCLC tissue samples compared with normal tissue samples, and may be a potential prognostic marker of NSCLC. Functional analyses demonstrated that SPINK1 promoted tumor cell growth and inhibited apoptosis through maintaining redox homeostasis by regulating the nuclear factor erythroid 2-related factor 2 pathways. It has been proposed that SPINK1 could be a prognostic marker of NSCLC and a novel antioxidant promoter under oxidative stress conditions in NSCLC.

LncRNA HOXA-AS3 Sponges miR-29c to Facilitate Cell Proliferation, Metastasis, and EMT Process and Activate the MEK/ERK Signaling Pathway in Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is a prevalent malignant tumor with high morbidity and mortality across the world. Recent findings have suggested that long noncoding (lnc)RNA HOXA-AS3 plays an important role in tumorigenesis and metastasis in a variety of cancers. However, the role of lncRNA HOXA-AS3 in the initiation and progression of HCC remains largely unclear. In the present study, HOXA-AS3 was highly expressed in HCC tumor tissues and cell lines. High HOXA-AS3 expression was correlated with low survival of HCC patients. Loss-of-function experiments showed that knockdown of HOXA-AS3 inhibited cell proliferation, migration, invasion, the epithelial-mesenchymal transition (EMT) process, and the mitogen-activated protein kinase/extracellular regulated protein kinase (MEK/ERK) signaling pathway in HCC. Molecular mechanism exploration uncovered that HOXA-AS3 could directly interact with and negatively regulate miR-29c. BMP1 is a downstream target gene of miR-29c, and HOXA-AS3 could regulate BMP1 expression by targeting miR-29c. miR-29c negatively regulated and BMP1 promoted the progression of HCC. Rescue experiments revealed that miR-29c inhibitor could partially counteract the impact induced by HOXA-AS3 knockdown in HCC. Taken together, our study is the first to show the interaction of HOXA-AS3 with miR-29c in facilitating cell proliferation, metastasis, EMT process, and MEK/ERK signaling pathway in HCC.

SPINK1 promotes cell growth and metastasis of lung adenocarcinoma and acts as a novel prognostic biomarker

Serine protease inhibitor Kazal type 1 (SPINK1) plays a role in protecting the pancreas against premature activation of trypsinogen and is involved in cancer progression. SPINK1 promoted LAC cells growth, migration, and invasion. Mechanistically, we found that SPINK1 promoted LAC cells migration and invasion via up-regulating matrix metalloproteinase 12 (MMP12). We observed that SPINK1 expression was only up-regulated in lung adenocarcinoma (LAC) tissues, and was an independent prognostic factor for poor survival. Our results indicate that SPINK1 might be a potential biomarker for LAC that promotes progression by MMP12. [BMB Reports 2018; 51(12): 648-653].

LncRNA CRNDE promotes the epithelial-mesenchymal transition of hepatocellular carcinoma cells via enhancing the Wnt/β-catenin signaling pathway

Colorectal neoplasia differentially expressed (CRNDE) is a significantly upregulated long noncoding RNA in hepatocellular carcinoma (HCC). CRNDE could promote cell proliferation, migration, and invasion, while its molecular mechanisms were still largely unclear. In this study, we investigated the expression and function of CRNDE. CRNDE was significantly upregulated in tumor tissues compared with adjacent normal tissues. In vitro, we revealed that knockdown of CRNDE inhibited cell proliferation, migration, and cell invasion capacities in HCC. Animal studies indicated that CRNDE knockdown represses both growth and metastasis of HCC tumors in vivo. Moreover, knockdown of CRNDE suppressed the cell epithelial-mesenchymal transition (EMT) process by increasing the expression of E-cadherin and ZO-1, whereas, decreasing the expression of N-cadherin, slug, twist, and vimentin in HCC cells. We also revealed that knockdown of CRNDE suppressed the Wnt/β-catenin signaling in HCC. Thus, CRNDE could modulate EMT of HCC cells and knockdown of CRNDE impaired the mesenchymal properties. CRNDE increased invasion of HCC cells might be through activating the Wnt/β-catenin signaling pathway.

Blockade of ARHGAP11A reverses malignant progress via inactivating Rac1B in hepatocellular carcinoma

Background

The molecular signaling events involving in high malignancy and poor prognosis of hepatocellular carcinoma (HCC) are extremely complicated. Blockade of currently known targets has not yet led to successful clinical outcome. More understanding about the regulatory mechanisms in HCC is necessary for developing new effective therapeutic strategies for HCC patients.

Methods

The expression of Rho GTPase-activating protein 11A (ARHGAP11A) was examined in human normal liver and HCC tissues. The correlations between ARHGAP11A expression and clinicopathological stage or prognosis in HCC patients were analyzed. ARHGAP11A was downregulated to determine its role in the proliferation, invasion, migration, epithelial-to-mesenchymal transition (EMT) development, and regulatory signaling of HCC cells in vitro and in vivo.

Results

ARHGAP11A exhibited high expression in HCC, and was significantly correlated with clinicopathological stage and prognosis in HCC patients. Moreover, ARHGAP11A facilitated Hep3B and MHCC97-H cell proliferation, invasion, migration and EMT development in vitro. ARHGAP11A knockdown significantly inhibited the in vivo growth and metastasis of HCC cells. Furthermore, ARHGAP11A directly interacted with Rac1B independent of Rho GTPase- activating activity. Rac1B blockade effectively interrupted ARHGAP11A-elicited HCC malignant phenotype. Meanwhile, upregulation of Rac1B reversed ARHGAP11A knockdown mediated mesenchymal-to-epithelial transition (MET) development in HCC cells.

Conclusion

ARHGAP11A facilitates malignant progression in HCC patients via ARHGAP11A-Rac1B interaction. The ARHGAP11A/Rac1B signaling could be a potential therapeutic target in the clinical treatment of HCC.

Electronic supplementary material

The online version of this article (10.1186/s12964-018-0312-4) contains supplementary material, which is available to authorized users.

Large-scale analysis reveals a novel risk score to predict overall survival in hepatocellular carcinoma

Background

Hepatocellular carcinoma (HCC) is a major cause of cancer mortality and an increasing incidence worldwide; however, there are very few effective diagnostic approaches and prognostic biomarkers.

Materials and methods

One hundred forty-nine pairs of HCC samples from Gene Expression Omnibus (GEO) were obtained to screen differentially expressed genes (DEGs) between HCC and normal samples. The Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway, Gene ontology enrichment analyses, and protein–protein interaction network were used. Cox proportional hazards regression analysis was used to identify significant prognostic DEGs, with which a gene expression signature prognostic prediction model was identified in The Cancer Genome Atlas (TCGA) project discovery cohort. The robustness of this panel was assessed in the GSE14520 cohort. We verified details of the gene expression level of the key molecules through TCGA, GEO, and qPCR and used immunohistochemistry for substantiation in HCC tissues. The methylation states of these genes were also explored.

Results

Ninety-eight genes, consisting of 13 upregulated and 85 downregulated genes, were screened out in three datasets. KEGG and Gene ontology analysis for the DEGs revealed important biological features of each subtype. Protein–protein interaction network analysis was constructed, consisting of 64 nodes and 115 edges. A subset of four genes (SPINK1, TXNRD1, LCAT, and PZP) that formed a prognostic gene expression signature was established from TCGA and validated in GSE14520. Next, the expression details of the four genes were validated with TCGA, GEO, and clinical samples. The expression panels of the four genes were closely related to methylation states.

Conclusion

This study identified a novel four-gene signature biomarker for predicting the prognosis of HCC. The biomarkers may also reveal molecular mechanisms underlying development of the disease and provide new insights into interventional strategies.

Resveratrol inhibits Erk1/2-mediated adhesion of cancer cells via activating PP2A-PTEN signaling network

Resveratrol, a natural polyphenol compound, has been shown to possess anticancer activity. However, how resveratrol inhibits cancer cell adhesion has not been fully elucidated. Here, we show that resveratrol suppressed the basal or type I insulin-like growth factor (IGF)-1-stimulated adhesion of cancer cells (Rh1, Rh30, HT29, and HeLa cells) by inhibiting the extracellular signal-regulated kinase 1/2 (Erk1/2) pathway. Inhibition of Erk1/2 with U0126, knockdown of Erk1/2, or overexpression of dominant-negative mitogen-activated protein kinase kinase 1 (MKK1) strengthened resveratrol's inhibition of the basal or IGF-1-stimulated of Erk1/2 phosphorylation and cell adhesion, whereas ectopic expression of constitutively active MKK1 attenuated the inhibitory effects of resveratrol. Further research revealed that both protein phosphatase 2A (PP2A) and phosphatase and tensin homolog (PTEN)-Akt were implicated in resveratrol-inactivated Erk1/2-dependent cell adhesion. Inhibition of PP2A with okadaic acid or overexpression of dominant-negative PP2A rendered resistance to resveratrol's suppression of the basal or IGF-1-stimulated phospho-Erk1/2 and cell adhesion, whereas expression of wild-type PP2A enhanced resveratrol's inhibitory effects. Overexpression of wild-type PTEN or dominant-negative Akt or inhibition of Akt with Akt inhibitor X strengthened resveratrol's inhibition of the basal or IGF-1-stimulated Erk1/2 phosphorylation and cell adhesion. Furthermore, inhibition of mechanistic/mammalian target of rapamycin (mTOR) with rapamycin or silencing mTOR enhanced resveratrol's inhibitory effects on the basal and IGF-1-induced inhibition of PP2A-PTEN, activation of Akt-Erk1/2, and cell adhesion. The results indicate that resveratrol inhibits Erk1/2-mediated adhesion of cancer cells via activating PP2A-PTEN signaling network. Our data highlight that resveratrol has a great potential in the prevention of cancer cell adhesion.