Epithelial Mesenchymal and Endothelial Mesenchymal Transitions in Hepatocellular Carcinoma: A Review

Mechanisms of Pharmacoresistance in Hepatocellular Carcinoma: New Drugs but Old Problems

Hepatocellular carcinoma (HCC) is a malignancy with poor prognosis when diagnosed at advanced stages in which curative treatments are no longer applicable. A small group of these patients may still benefit from transarterial chemoembolization. The only therapeutic option for most patients with advanced HCC is systemic pharmacological treatments based on tyrosine kinase inhibitors (TKIs) and immunotherapy. Available drugs only slightly increase survival, as tumor cells possess additive and synergistic mechanisms of pharmacoresistance (MPRs) prior to or enhanced during treatment. Understanding the molecular basis of MPRs is crucial to elucidate the genetic signature underlying HCC resistome. This will permit the selection of biomarkers to predict drug treatment response and identify tumor weaknesses in a personalized and dynamic way. In this article, we have reviewed the role of MPRs in current first-line drugs and the combinations of immunotherapeutic agents with novel TKIs being tested in the treatment of advanced HCC.

Microenvironment of Cancer Stem Cells

Microenvironment of cancer stem cells (CSCs) consists of a variety of cells and inter-cellular matrix and communications of the components. The microenvironment of CSCs maintains the stemness feature of the CSCs. Several cell types which communicate each other via signaling molecules surrounding CSCs are main factors of the CSC microenvironment. A key question is "What kind of information the cells exchange in the CSC microenvironment?" to reveal the microenvironment and CSC features. Components and molecular markers of CSC microenvironment, signaling cross-talks in CSC microenvironment, and targeting CSC microenvironment are focused in this review.

Identification and clinical validation of EMT-associated prognostic features based on hepatocellular carcinoma

BACKGROUND

The aim of this study was to construct a model based on the prognostic features associated with epithelial-mesenchymal transition (EMT) to explore the various mechanisms and therapeutic strategies available for the treatment of metastasis and invasion by hepatocellular carcinoma (HCC) cells.

METHODS

EMT-associated genes were identified, and their molecular subtypes were determined by consistent clustering analysis. The differentially expressed genes (DEGs) among the molecular subtypes were ascertained using the limma package and they were subjected to functional enrichment analysis. The immune cell scores of the molecular subtypes were evaluated using ESTIMATE, MCPcounter, and GSCA packages of R. A multi-gene prognostic model was constructed using lasso regression, and the immunotherapeutic effects of the model were analyzed using the Imvigor210 cohort. In addition, immunohistochemical analysis was performed on a cohort of HCC tissue to validate gene expression.

RESULTS

Based on the 59 EMT-associated genes identified, the 365-liver hepatocellular carcinoma (LIHC) samples were divided into two subtypes, C1 and C2. The C1 subtype mostly showed poor prognosis, had higher immune scores compared to the C2 subtype, and showed greater correlation with pathways of tumor progression. A four-gene signature construct was fabricated based on the 1130 DEGs among the subtypes. The construct was highly robust and showed stable predictive efficacy when validated using datasets from different platforms (HCCDB18 and GSE14520). Additionally, compared to currently existing models, our model demonstrated better performance. The results of the immunotherapy cohort showed that patients in the low-risk group have a better immune response, leading to a better patient's prognosis. Immunohistochemical analysis revealed that the expression levels of the FTCD, PON1, and TMEM45A were significantly over-expressed in 41 normal samples compared to HCC samples, while that of the G6PD was significantly over-expressed in cancerous tissues.

CONCLUSIONS

The four-gene signature construct fabricated based on the EMT-associated genes provides valuable information to further study the pathogenesis and clinical management of HCC.

UBE2T promotes β-catenin nuclear translocation in hepatocellular carcinoma through MAPK/ERK-dependent activation

Ubiquitin‐conjugating enzyme E2T (UBE2T) has been implicated in many types of cancer including hepatocellular carcinoma (HCC). Epithelial–mesenchymal transition (EMT) process plays a fundamental role during tumor metastasis and progression. However, the molecular mechanisms underlying EMT in HCC in accordance with UBE2T still remain unknown. In this study, we showed that UBE2T overexpression augmented the oncogenic properties and specifically EMT in HCC cell lines, while its silencing attenuated them. UBE2T affected the activation of EMT‐associated signaling pathways: MAPK/ERK, AKT/mTOR, and Wnt/β‐catenin. In addition, we revealed that the epithelial protein complex of E‐cadherin/β‐catenin, a vital regulator of signal transduction in tumor initiation and progression, was totally disrupted at the cell membrane. In particular, we observed that UBE2T overexpression led to E‐cadherin loss accompanied by a simultaneous elevation of both cytoplasmic and nuclear β‐catenin, while its silencing resulted in a strong E‐cadherin turnover at the cell membrane. Interestingly, chemical inhibition of the MAPK/ERK, AKT/mTOR, and Wnt/β‐catenin signaling pathways demonstrated that the nuclear translocation of β‐catenin and subsequent EMT was enhanced mainly by MAPK/ERK. Collectively, our findings demonstrate the UBE2T/MAPK‐ERK/β‐catenin axis as a critical regulator of cell state transition and EMT in HCC.

Interaction between cadherins, vimentin, and V-set and immunoglobulin domain containing 1 in gastric-type hepatocellular carcinoma

In hepatocellular carcinomas (HCCs), the role of the cell surface protein V-set and immunoglobulin domain containing 1 (VSIG1), which is known as a specific marker of the gastric mucosa and testis, has not yet been determined. We examined VSIG1 immunohistochemical (IHC) expression in 105 consecutive samples provided by HCC patients, along with the IHC expression of three of the biomarkers known to be involved in the epithelial-mesenchymal transition (EMT): vimentin (VIM), and E- and N-cadherin (encoded by CDH1 and CDH2 genes). IHC subcellular localization of thyroid transcription factor 1 (TTF1), in which nuclear-to-cytoplasmic translocation is known to cause a lineage shift from lung to gastric-type adenocarcinoma, was also checked. The obtained data were validated using the miRNET program. In the examined HCC samples, VSIG1 expression was observed in the cytoplasm of normal hepatocytes and downregulated in 47 of the 105 HCCs (44.76%). In 29 cases (27.62%), VSIG1 was co-expressed with cytoplasmic TTF1. VSIG1 expression was positively correlated with both E-cadherin and N-cadherin and negatively correlated with VIM (p < 0.0001). The VSIG1+/E-cadherin+/N-cadherin-/VIM phenotype was seen in 13 cases (12.4%) and was characteristic of well-differentiated (G1/2) carcinomas diagnosed in pT1/2 stages. Like pulmonary carcinomas, simultaneous cytoplasmic positivity of HCC cells for VSIG1 and TTF1 may be a potential indicator of a lineage shift from conventional to gastric-type HCC. The E-cadherin/VSIG1 complex can help suppress tumor growth by limiting HCC dedifferentiation. The miRNET-based interaction between VSIG1/VIM/CDH1/CDH2 genes might be interconnected by miR-200b-3p, a central regulator of EMT which also targets VIM and VSIG1.

Traditional Chinese medicine for prevention and treatment of hepatocellular carcinoma: A focus on epithelial-mesenchymal transition

Hepatocellular carcinoma (HCC) is one of the most prevalent malignant cancers worldwide. Epithelial-mesenchymal transition (EMT), which endows epithelial cells with mesenchymal properties, plays an important role in the early stages of metastasis. Conventional cancer therapies have promising effects, but issues remain, such as high rates of metastasis and drug resistance. Thus, exploring and evaluating new therapies is an urgent need. Traditional Chinese medicines (TCMs) have been acknowledged for their multi-target and coordinated intervention effects against HCC. Accumulating evidence indicates that TCM can inhibit the malignancy of cells and the progression of EMT in HCC. However, studies on the effects of TCM on EMT in HCC are scarce. In this review, we summarized recent developments in anti-EMT TCMs and formulae, focusing on their underlying pharmacological mechanisms, to provide a foundation for further research on the exact mechanisms through which TCM affects EMT in HCC.

Association of phenotypic transformation of circulating tumor cells and early recurrence in patients with hepatocellular carcinoma following liver transplantation

BACKGROUND

CTCs play a critical role in the diagnosis and prognosis of liver cancer. However, there are few studies on whether different types of CTCs can predict the prognosis in patients with HCC following LT.

METHODS

Retrospective data including CTCs detected by the CanPatrolTM platform combined with RNA-ISH were collected and analyzed on 56 patients from December 2016 to December 2019 at the Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong Province, China.

RESULTS

During the study period, fifty-six patients (51 males, 5 females) were included with an mean age of 52 ± 9 years. The 1-, 2- and 3-year recurrence rates of postoperative interstitial CTC-positive and CTC-negative groups were 21.7% vs 10.8%, 37.5% vs 10.8% and 55.5% vs 10.8%, confirming a statistically significant difference between the 2 groups (p = 0.044). The 1-, 2- and 3-year recurrence rates of the increasing interstitial CTCs group were 25.2%, 36.9% and 66.9%, while 12.6%, 24.4% and 24.4% in the decreasing and unchanged group, indicating a significant difference (p = 0.038).

CONCLUSION

CanPatrolTM platform presents a superior analytical sensitivity, and may be used as a dynamic monitoring tool for CTCs. And interstitial CTCs which are more aggressive and metastatic caused by EMT can be regarded as a predictor of post-transplant tumor recurrence after LT for HCC.

Epithelial-to-Mesenchymal Transition and Neoangiogenesis in Laryngeal Squamous Cell Carcinoma

Simple summary

The mechanism of epithelial–mesenchymal transition is fundamental for carcinogenesis, tumor progression, cancer cell invasion, metastasis, recurrence, and therapy resistance, resulting in cellular junction degradation and increased cellular motility. The same factors that drive epithelial cells toward a mesenchymal phenotype may also drive endothelial cells toward a proangiogenic phenotype. This study aimed to investigate a potential interplay between epithelial–mesenchymal transition and angiogenesis in laryngeal carcinoma. In our study, univariate Cox regression identified pN+ status and Slug expression as predictive of disease-free survival, while a trend toward significance emerged for CD105-assessed microvessel density and N-cadherin expression. In the multivariate Cox regression model, pN-status, Slug, and N-cadherin expressions retained their significant values in predicting disease-free survival. Data from our study support the hypothesis of a mutual concurrence of epithelial–mesenchymal transition and angiogenesis in the development of an aggressive phenotype in laryngeal squamous cell carcinoma.

Abstract

The mechanism of epithelial–mesenchymal transition (EMT) is fundamental for carcinogenesis, tumor progression, cancer cell invasion, metastasis, recurrence, and therapy resistance, comprising important events, such as cellular junction degradation, downregulation of epithelial phenotype markers, overexpression of mesenchymal markers, and increase in cellular motility. The same factors that drive epithelial cells toward a mesenchymal phenotype may also drive endothelial cells toward a proangiogenic phenotype. The aim of this exploratory study was to investigate a potential interplay between EMT and angiogenesis (quantified through CD105 expression) in laryngeal carcinoma (LSCC). CD105-assessed microvessel density (MVD) and EMT markers (E-cadherin, N-cadherin, Snail, Slug, Zeb1, and Zeb2) were assessed on 37 consecutive LSCC cases. The univariate Cox regression model identified pN+ status (p = 0.0343) and Slug expression (p = 0.0268) as predictive of disease-free survival (DFS). A trend toward significance emerged for CD105-assessed MVD (p = 0.0869) and N-cadherin expression (p = 0.0911). In the multivariate Cox model, pN-status, Slug, and N-cadherin expressions retained their significant values in predicting DFS (p = 0.0346, p = 0.0430, and p = 0.0214, respectively). Our data support the hypothesis of a mutual concurrence of EMT and angiogenesis in driving LSCC cells toward an aggressive phenotype. To better characterize the predictive performance of prognostic models based on EMT and angiogenesis, further large-scale prospective studies are required.

Epithelial-Mesenchymal Transition Gene Signature Related to Prognostic in Colon Adenocarcinoma

Colon adenocarcinoma (COAD) remains an important cause of cancer-related mortality worldwide. Epithelial–mesenchymal transition (EMT) is a key mechanism, promoting not only the invasive or metastatic phenotype but also resistance to therapy. Using bioinformatics approaches, we studied the alteration on EMT related genes and its implication on COAD prognostic based on public datasets. For the EMT mechanisms, two overexpressed genes were identified (NOX4 and IGF2BP3), as well as five downregulated genes (BMP5, DACT3, EEF1A2, GCNT2 and SFRP1) that were related to prognosis in COAD. A qRT-PCR validation step was conducted in a COAD patient cohort comprising of 29 tumor tissues and 29 normal adjacent tissues, endorsing the expression level for BMP5, as well as for two of the miRNAs targeting key EMT related genes, revealing upregulation of miR-27a-5p and miR-146a-5p. The EMT signature can be used to develop a panel of biomarkers for recurrence prediction in COAD patients, which may contribute to the improvement of risk stratification for the patients.

LncRNA XIST promotes liver cancer progression by acting as a molecular sponge of miR-200b-3p to regulate ZEB1/2 expression

Objective

To evaluate the predictive value of long non-coding RNA (lncRNA) X-inactive specific transcript (XIST) for survival, and determine the involvement of miRNA(miR)-200b-3p and zinc finger E-box-binding homeobox (ZEB) 1/2 in the pro-tumor effect of lncRNA XIST in liver cancer.

Methods

We evaluated lncRNA XIST expression in liver cancer tissues and cell lines by quantitative reverse transcription polymerase chain reaction (RT-qPCR) and analyzed the correlation between its expression and overall survival of liver cancer patients by Kaplan–Meier analysis. Its effects on cell proliferation, migration, and invasion were analyzed by Cell-Counting Kit-8 and Transwell assays. The association between lncRNA XIST and miR-200b-3p, and the effects of lncRNA XIST on ZEB1/2 expression were explored using luciferase reporter assays, real-time PCR, and western blotting.

Results

The lncRNA XIST was significantly upregulated in liver cancer, and increased lncRNA XIST expression was associated with a poor prognosis. The lncRNA XIST promoted liver cancer cell proliferation, migration, and invasion in vitro, and acted as a molecular sponge for miR-200b-3p, and also regulated the expression of ZEB1/2 via miR-200b-3p.

Conclusion

The lncRNA XIST is an oncogenic lncRNA that promotes liver cancer metastasis, and its pro-metastatic phenotype can be partially attributed to the lncRNA XIST/miR-200b-3p/ZEB1/2 signaling axis.

Falcarindiol Enhances Cisplatin Chemosensitivity of Hepatocellular Carcinoma via Down-Regulating the STAT3-Modulated PTTG1 Pathway

Hepatocellular carcinoma (HCC) is the most frequent primary liver malignancy globally and the third leading cause of cancer-related death. Chemotherapy is one of the main methods in treating HCC, while recent studies have found that the resistance of HCC to chemotherapeutic drugs reduces the efficacy of the chemotherapy. Falcarindiol (FAD) is a cytotoxic and anti-inflammatory polyacetylenic oxylipin found in food plants of the carrot family (Apiaceae), while its role in HCC remains to be explored. Here, HCC cells (Huh7 and LM3) were treated with FAD at different doses. Cell proliferation was tested by the cell counting kit-8 (CCK-8) method and colony formation assay, while the apoptosis was monitored by flow cytometry. The profiles of apoptosis-related proteins (Bax, bcl2, and Caspase-3), DNA repair proteins (Rad51, BRCA1, and MDC1), and the signal transducer and activator of transcription 3 (STAT3)/Pituitary Tumor Transforming Gene 1 (PTTG1) were verified by western blot (WB) or quantitative reverse transcription-polymerase chain reaction (qRT-PCR). The interaction between STAT3 and PTTG1 was verified by immunoprecipitation (IP). In addition, a xenograft tumor model was constructed in mice to explore the anti-tumor effects of FAD in vivo, and immunohistochemistry (IHC) was performed to count the number of Ki67-stained cells. As a result, FAD inhibited HCC cell proliferation and DNA repair, facilitated their apoptosis, and also enhanced cisplatin (DDP) chemosensitivity. The Combination Index (CI) evaluation showed that FAD and DDP had synergistic effects in repressing HCC cell proliferation. Besides, FAD dampened the STAT3/PTTG1 pathway expression. Further studies revealed that inhibiting STAT3 enhanced the inhibitive effect of FAD on HCC cells, whereas overexpressing PTTG1 attenuated the anti-tumor effect of FAD. Overall, our study illustrated that FAD is a potential anticancer drug and strengthens the chemosensitivity of HCC cells to DDP by inhibiting the STAT3/PTTG1 pathway.

Generation and identification of endothelial-specific Hrh2 knockout mice

Histamine H₂ receptor (HRH2) is closely associated with the development of cardiovascular and cerebrovascular diseases. However, systematic Hrh2 knockout mice did not exactly reflect the HRH2 function in specific cell or tissue types. To better understand the physiological and pathophysiological functions of endothelial HRH2, this study constructed a targeting vector that contained loxp sites flanking the ATG start codon located in Hrh2 exon 2 upstream and a neomycin (Neo) resistance gene flanked by self-deletion anchor sites within the mouse Hrh2 allele. The targeting vector was then electroporated into C57BL/6J embryonic stem (ES) cells, and positively targeted ES cell clones were micoinjected into C57BL/6J blastocysts, which were implanted into pseudopregnant females to obtain chimeric mice. The F1 generation of Hrh2^flox/+ mice was generated via crossing chimeric mice with wild-type mice to excise Neo. We also successfully generated endothelial cell-specific knockout (ECKO) mice by crossing Hrh2^flox/+ mice with Cdh5-Cre mice that specifically express Cre in endothelial cells and identified that Hrh2 deletion was only observed in endothelial cells. Hrh2^flox/+ and Hrh2^ECKO mice were normal, healthy and fertile and did not display any obvious abnormalities. These novel animal models will create new prospects for exploring roles of HRH2 during the development and treatment of related diseases.

Benefits of the 8th American Joint Committee on Cancer System for Hepatocellular Carcinoma Staging

PURPOSE

We aimed to emphasize the prognostic impact of differences included in the 8th versus the previous 7th edition of AJCC (American Joint Committee on Cancer) Cancer Staging manual for hepatocellular carcinoma (HCC).

METHODS

A number of 87 consecutive HCCs were retrospectively evaluated and staged, using the 7th and 8th edition of AJCC staging systems. The clinicopathological parameters were correlated with the overall survival rate. No preoperative chemotherapy was received by any of the patients.

RESULTS

According to the 7th edition of AJCC manual, 52 of the 87 cases were staged as pT2 and 35 as pT1. After restaging, according to the 8th edition, 23 of the 52 pT2 cases were understaged as pT1b, and the rest of the 29 remained as pT2. Regarding the 35 HCCs classified as pT1, using 7th edition, all of them were restaged as pT1a. Compared to the 7th staging system, using the 8th edition of AJCC manual, the percentage of pT2 tumors significantly decreased, from 59.77 to 33.33%. The patient's gender, age, tumor focality, and grade of differentiation did not prove to have any prognostic value. Regarding pT stage, it does not influence the overall survival rate, independently from the used staging system.

CONCLUSION

The staging criteria, in the most recent edition of AJCC, are simplified and allowed tumor understaging. These changes do not have independent prognostic value. The prognostic impact of pT understaging should be evaluated in larger cohorts.

7-ketocholesterol induces endothelial-mesenchymal transition and promotes fibrosis: implications in neovascular age-related macular degeneration and treatment

Oxidized cholesterols and lipids accumulate in Bruch's membrane in age-related macular degeneration (AMD). It remains unknown what causal relationship exists between these substances and AMD pathophysiology. We addressed the hypothesis that a prevalent form, 7-ketocholesterol (7KC), promotes choroidal endothelial cell (CEC) migration and macular neovascularization in AMD. Compared to control, 7KC injection caused 40% larger lectin-stained lesions, but 70% larger lesions measured by optical coherence tomography one week after laser-injury. At two weeks, 7KC-injected eyes had 86% larger alpha smooth muscle actin (αSMA)-labeled lesions and more collagen-labeling than control. There was no difference in cell death. 7KC-treated RPE/choroids had increased αSMA but decreased VE-cadherin. Compared to control-treated CECs, 7KC unexpectedly reduced endothelial VE-cadherin, CD31 and VEGFR2 and increased αSMA, fibroblast activation protein (FAP) and transforming growth factor beta (TGFβ). Inhibition of TGFβ receptor-mediated signaling by SB431542 abrogated 7KC-induced loss of endothelial and increase in mesenchymal proteins in association with decreased transcription factor, SMAD3. Knockdown of SMAD3 partially inhibited 7KC-mediated loss of endothelial proteins and increase in αSMA and FAP. Compared to control, 7KC-treatment of CECs increased Rac1GTP and migration, and both were inhibited by the Rac1 inhibitor; however, CECs treated with 7KC had reduced tube formation. These findings suggest that 7KC, which increases in AMD and with age, induces mesenchymal transition in CECs making them invasive and migratory, and causing fibrosis in macular neovascularization. Further studies to interfere with this process may reduce fibrosis and improve responsiveness to anti-VEGF treatment in non-responsive macular neovascularization in AMD.

Small hepatitis B virus surface antigen promotes malignant progression of hepatocellular carcinoma via endoplasmic reticulum stress-induced FGF19/JAK2/STAT3 signaling

Chronic hepatitis B virus (HBV) infection is one of the major global health problems. Although the small protein of hepatitis B virus surface antigen (HBsAg), SHBs, is the most abundant HBV viral protein, its pathogenic role and molecular mechanism in malignant progression of HBV-related hepatocellular carcinoma (HCC) remain largely unknown. Here we reported that SHBs expression induced epithelial-mesenchymal transition (EMT) process in HCC cells and significantly increased their migratory and invasive ability as well as metastatic potential. Mechanistically, SHBs expression in HCC cells induced endoplasmic reticulum (ER) stress that activated the activating transcription factor 4 (ATF4) to increase the expression and secretion of fibroblast growth factor 19 (FGF19). The autocrine released FGF19 in turn activated JAK2/STAT3 signaling for induction of EMT process in HCC. Notably, SHBs was positively correlated with the expression of mesenchymal markers, the phosphorylation status of JAK2 and STAT3 as well as FGF19 levels in human HCC samples. HCC patients with SHBs positive had a more advanced clinical stage and worse prognosis. These results suggest an important role of SHBs in the metastasis and progression of HCC and may highlight a potential target for preventive and therapeutic intervention of HBV-related HCC and its malignant progression.

Comprehensive Analysis of the Expression of Key Genes Related to Hippo Signaling and Their Prognosis Impact in Ovarian Cancer

The Hippo signaling pathway, one of the most conserved in humans, controlling dimensions of organs and tumor growth, is frequently deregulated in several human malignancies, including ovarian cancer (OC). The alteration of Hippo signaling has been reported to contribute to ovarian carcinogenesis and progression. However, the prognostic roles of individual Hippo genes in OC patients remain elusive. Herein we investigated the expression level and prognostic value of key Hippo genes in OC using online databases, followed by a qRT-PCR validation step in an additional patient cohort. Using the GEPIA database, we observed an increased level for TP53 and reduced expression level for LATS1, LATS2, MST1, TAZ, and TEF in tumor tissue versus normal adjacent tissue. Moreover, LATS1, LATS2, TP53, TAZ, and TEF expression levels have prognostic significance correlated with progression-free survival. The qRT-PCR validation step was conducted in an OC patient cohort comprising 29 tumor tissues and 20 normal adjacent tissues, endorsing the expression level for LATS1, LATS2, and TP53, as well as for two of the miRNAs targeting the TP53 gene, revealing miR-25-3p upregulation and miR-181c-5p downregulation. These results display that there are critical prognostic value dysregulations of the Hippo genes in OC. Our data demonstrate the major role the conserved Hippo pathway presents in tumor control, underlying potential therapeutic strategies and controlling several steps modulated by miRNAs and their target genes that could limit ovarian cancer progression.

USP2-Related Cellular Signaling and Consequent Pathophysiological Outcomes

Ubiquitin specific protease (USP) 2 is a multifunctional deubiquitinating enzyme. USP2 modulates cell cycle progression, and therefore carcinogenesis, via the deubiquitination of cyclins and Aurora-A. Other tumorigenic molecules, including epidermal growth factor and fatty acid synthase, are also targets for USP2. USP2 additionally prevents p53 signaling. On the other hand, USP2 functions as a key component of the CLOCK/BMAL1 complex and participates in rhythmic gene expression in the suprachiasmatic nucleus and liver. USP2 variants influence energy metabolism by controlling hepatic gluconeogenesis, hepatic cholesterol uptake, adipose tissue inflammation, and subsequent systemic insulin sensitivity. USP2 also has the potential to promote surface expression of ion channels in renal and intestinal epithelial cells. In addition to modifying the production of cytokines in immune cells, USP2 also modulates the signaling molecules that are involved in cytokine signaling in the target cells. Usp2 knockout mice exhibit changes in locomotion and male fertility, which suggest roles for USP2 in the central nervous system and male genital tract, respectively. In this review, we summarize the cellular events with USP2 contributions and list the signaling molecules that are upstream or downstream of USP2. Additionally, we describe phenotypic differences found in the in vitro and in vivo experimental models.

Development and External Validation of a Novel Immune Checkpoint-Related Gene Signature for Prediction of Overall Survival in Hepatocellular Carcinoma

Objective: The purpose of this study was to develop and validate a novel immune checkpoint-related gene signature for prediction of overall survival (OS) in hepatocellular carcinoma (HCC). Methods: mRNA expression profiles and clinical follow-up information were obtained in the International Cancer Genome Consortium database. An external dataset from The Cancer Genome Atlas (TCGA) Liver Hepatocellular Carcinoma database was used to validate the results. The univariate and multivariate Cox regression analyses were performed based on the differentially expressed genes. We generated a four-mRNA signature to predict patient survival. Furthermore, the reliability and validity were validated in TCGA cohort. An integrated bioinformatics approach was performed to evaluate its diagnostic and prognostic value. Results: A four-gene (epidermal growth factor, mutated in colorectal cancer, mitogen-activated protein kinase kinase 2, and NRAS proto-oncogene, GTPase) signature was built to classify patients into two risk groups using a risk score with different OS in two cohorts (all P < 0.0001). Multivariate regression analysis demonstrated the signature was an independent predictor of HCC. Furthermore, the signature presented an excellent diagnostic power in differentiating HCC and adjacent tissues. Immune cell infiltration analysis revealed that the signature was associated with a number of immune cell subtypes. Conclusion: We identified a four-immune checkpoint-related gene signature as a robust biomarker with great potential for clinical application in risk stratification and OS prediction in HCC patients and could be a potential indicator of immunotherapy in HCC. The diagnostic signature had been validated to accurately distinguish HCC from adjacent tissues.

Identification of potential biomarkers of peripheral blood mononuclear cell in hepatocellular carcinoma using bioinformatic analysis: A protocol for systematic review and meta-analysis

BACKGROUND

Hepatocellular carcinoma (HCC) is the cause of an overwhelming number of cancer-related deaths across the world. Developing precise and noninvasive biomarkers is critical for diagnosing HCC. Our research was designed to explore potentially useful biomarkers of host peripheral blood mononuclear cell (PBMC) in HCC by integrating comprehensive bioinformatic analysis.

METHODS

Gene expression data of PBMC in both healthy individuals and patients with HCC were extracted from the Gene Expression Omnibus (GEO) to identify differentially expressed genes (DEGs). The gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis were applied to annotate the function of DEGs. Protein-protein interaction analysis was performed to screen the hub genes from DEGs. cBioportal database analysis was performed to assess the prognostic significance of hub genes. The Cancer Cell Line Encyclopedia (CCLE) and The Human Protein Atlas (HPA) database analyses were performed to confirm the expression levels of the hub genes in HCC cells and tissue.

RESULTS

A total of 95 DEGs were screened. Results of the GO analysis revealed that DEGs were primarily involved in platelet degranulation, cytoplasm, and protein binding. Results of the KEGG analysis indicated that DEGs were primarily enriched in focal adhesion. Five genes, namely, myosin light chain kinase (MYLK), interleukin 1 beta (IL1B), phospholipase D1 (PLD1), cortactin (CTTN), and moesin (MSN), were identified as hub genes. A search in the CCLE and HPA database showed that the expression levels of these hub genes were remarkably increased in the HCC samples. Survival analysis revealed that the overexpression of MYLK, IL1B, and PLD1 may have a significant effect on HCC survival. The aberrant high expression levels of MYLK, IL1B, and PLD1 strongly indicated worse prognosis in patients with HCC.

CONCLUSIONS

The identified hub genes may be closely linked with HCC tumorigenicity and may act as potentially useful biomarkers for the prognostic prediction of HCC in PBMC samples.

Hedgehog Signaling, a Critical Pathway Governing the Development and Progression of Hepatocellular Carcinoma

Hedgehog (Hh) signaling is a classic morphogen in controlling embryonic development and tissue repairing. Aberrant activation of Hh signaling has been well documented in liver cancer, including hepatoblastoma, hepatocellular carcinoma (HCC) and cholangiocarcinoma. The present review aims to update the current understanding on how abnormal Hh signaling molecules modulate initiation, progression, drug resistance and metastasis of HCC. The latest relevant literature was reviewed with our recent findings to provide an overview regarding the molecular interplay and clinical relevance of the Hh signaling in HCC management. Hh signaling molecules are involved in the transformation of pre-carcinogenic lesions to malignant features in chronic liver injury, such as nonalcoholic steatohepatitis. Activation of GLI target genes, such as ABCC1 and TAP1, is responsible for drug resistance in hepatoma cells, with a CD133⁻/EpCAM⁻ surface molecular profile, and GLI1 and truncated GLI1 account for the metastatic feature of the hepatoma cells, with upregulation of matrix metalloproteinases. A novel bioassay for the Sonic Hh ligand in tissue specimens may assist HCC diagnosis with negative α-fetoprotein and predict early microvascular invasion. In-depth exploration of the Hh signaling deepens our understanding of its molecular modulation in HCC initiation, drug sensitivity and metastasis, and guides precise management of HCC on an individual basis.

CircPUM1 promotes hepatocellular carcinoma progression through the miR-1208/MAP3K2 axis

Hepatocellular carcinoma (HCC) is a common disease with a significant mortality, and there is no effective treatment for advanced patients. Growing evidence indicates that circRNAs are closely related to HCC progression, may be used as biomarkers and targets for the diagnosis and treatment of HCC. Recent researches have shown that circPUM1 may play an oncogene role in a variety of human cancers, but its role in HCC development has not been reported. Our study found that circPUM1 could promote the proliferation, migration and invasion of HCC cells in vitro. In addition, in vivo studies showed that circPUM1 could increase the development of HCC tumours and regulate the expression of EMT-related proteins. Furthermore, we demonstrated that circPUM1 could promote the development of HCC by up-regulating the expression of MAP3K2 via sponging miR-1208. Our study suggested that circPUM1 may be a potential therapeutic target for HCC.

Multifaceted modifications for a cell size-based circulating tumor cell scope technique hold the prospect for large-scale application in general populations

Circulating tumor cells (CTCs) indicate the diagnosis and prognosis of cancer patients, together with benefiting individual treatment and anticancer drug development. However, their large-scale application in general population still requires systematically multifaceted modifications for currently proprietary new technologies based on filtration. We primitively utilized a cell size-based platform to evaluate the recovery efficiency of spiked abnormal cell lines and analyzed circulating abnormal cells (CACs). To dissect the subpopulations of CACs, we conducted immunofluorescent (IF) staining with a combination of unique biomarkers of CTCs and circulating endothelial cells (CECs). Furthermore, we improved the CTC screening system by assessing the feasibility of transferring CTCs for automatic IF analysis, together with simulating and optimizing the circumstances for long-term CTC storage and transportation. We detected CACs in 15 HD candidates with CTC characteristics such as abnormally large cytomorphology, high nuclear-cytoplasmic ratio, and positive for panCK or VIM staining. Thereafter, we improved accuracy of the platform by distinguishing CTCs from CECs, which satisfied the elementary requirement for small-scale CTC screening in HD candidates. Finally, large-scale CTC screening in general population was available after multifaceted modifications including automatic analysis by transferring CTCs on slides, choosing the appropriate blood-collecting tube, optimizing the conditions for long-term CTC storage and transportation, and evaluating the potential effect on the CTC phenotype. Hence, we systematically modified the scope of technique parameters, improved the accuracy of early cancer detection, and made it realizable for large-scale CTC or CEC screening in general population.

Arctigenin Suppressed Epithelial-Mesenchymal Transition Through Wnt3a/β-Catenin Pathway in PQ-Induced Pulmonary Fibrosis

Arctigenin (ATG), a major bioactive substance of Fructus Arctii, counters renal fibrosis; however, whether it protects against paraquat (PQ)-induced lung fibrosis remains unknown. The present study was to determine the effect of ATG on PQ-induced lung fibrosis in a mouse model and the underlying mechanism. Firstly, we found that ATG suppressed PQ-induced pulmonary fibrosis by blocking the epithelial-mesenchymal transition (EMT). ATG reduced the expressions of Vimentin and α-SMA (lung fibrosis markers) induced by PQ and restored the expressions of E-cadherin and Occludin (two epithelial markers) in vivo and in vitro. Besides, the Wnt3a/β-catenin signaling pathway was significantly activated in PQ induced pulmonary fibrosis. Further analysis showed that pretreatment of ATG profoundly abrogated PQ-induced EMT-like phenotypes and behaviors in A549 cells. The Wnt3a/β-catenin signaling pathway was repressed by ATG treatment. The overexpression of Wnt3a could weaken the therapeutic effect of ATG in A549 cells. These findings suggested that ATG could serve as a new therapeutic candidate to inhibit or even reverse EMT-like changes in alveolar type II cells during PQ-induced lung fibrosis, and unraveled that the Wnt3a/β-catenin pathway might be a mechanistic tool for ATG to control pulmonary fibrosis.

Circular RNA circGSK3B Promotes Cell Proliferation, Migration, and Invasion by Sponging miR-1265 and Regulating CAB39 Expression in Hepatocellular Carcinoma

Circular RNAs (circRNAs) have important regulatory roles in the development of various cancers. However, the biological functions and potential molecular mechanisms of circRNAs in hepatocellular carcinoma (HCC) are still unclear. In this study, we investigated the role of a new circRNA-circGSK3B (hsa_circ_0003763) and its molecular mechanism in HCC. We found that circGSK3B was highly expressed in HCC tissues and HCC cell lines. Additionally, the expression level of circGSK3B significantly correlated with HCC tumor size and vascular invasion. Functionally, we confirmed that circGSK3B can promote the proliferation, migration, and invasion of HCC cells in vivo and in vitro. In terms of mechanism, we demonstrated that circGSK3B acts as a miR-1265 sponge, positively regulates the target gene CAB39, and promotes the reprogramming of glutamine metabolism, thereby promoting the progression of HCC. Finally, the classic RNA binding protein QKI was observed to participate in the biogenesis of circGSK3B. In summary, we proved that the circGSK3B-miR-1265-CAB39 axis can promote the proliferation, migration, invasion of HCC cells, indicating that circGSKB may serve as a promising diagnostic and prognostic marker in HCC.

Specific expression of survivin, SOX9, and CD44 in renal tubules in adaptive and maladaptive repair processes after acute kidney injury in rats

Acute kidney injury (AKI) is thought to be a reversible condition; however, growing evidence has suggested that AKI may be associated with subsequent development of chronic kidney disease. Although renal tubules have intrinsic regeneration capacity, disruption of the regeneration mechanisms leads to irreversible interstitial fibrosis. In this study, we investigated immunohistochemical markers of renal tubules in adaptive and maladaptive repair processes to predict AKI reversibility. Histopathological analysis demonstrated that regenerative tubules and dilated tubules were observed in the kidneys of AKI model rats after ischemia/reperfusion (I/R). Regenerative tubules gradually redifferentiated after I/R, whereas dilated tubules exhibited no tendency for redifferentiation. In fibrotic areas of the kidney in renal fibrosis model rats subjected to I/R, renal tubules were dilated or atrophied. There results suggested that the histopathological features of renal tubules in the maladaptive repair were dilation or atrophy. From microarray data of regenerative tubules, survivin, SOX9, and CD44 were extracted as candidate markers. Immunohistochemical analysis demonstrated that survivin and SOX9 were expressed in regenerative tubules, whereas SOX9 was also detected in renal tubules in fibrotic areas. These findings indicated that survivin and SOX9 contributed to renal tubular regeneration, whereas sustained SOX9 expression may be associated to fibrosis. CD44 was expressed in dilated tubules in the kidneys of AKI model rats and in the tubules of fibrotic areas of renal fibrosis model rats, suggesting that CD44 was expressed in renal tubules in maladaptive repair. Thus, these factors could be useful markers for detecting disruption of the regenerative mechanisms of renal tubules.

Down-Regulated CMTM2 Promotes Epithelial-Mesenchymal Transition in Hepatocellular Carcinoma

Background

Our recent study identified that human chemokine-like factor (CKLF)-like MARVEL transmembrane domain-containing family member 2 (CMTM2) was deregulated in hepatocellular carcinoma (HCC) tissues and posed as a potential tumor suppressor. However, the mechanism of CMTM2 in HCC occurrence and development has not been well elaborated.

Materials and Methods

The expression of CMTM2 was knocked-down by RNA interruption in Huh-7 and SMMC7721 cells. Cell proliferation ability was detected by CCK8 test and colony formation assay. The cell invasion and migration were measured by wound healing and Transwell assay.

Results

We found that the cell proliferation was significantly increased by interruption of CMTM2 expression, both in Huh-7 and SMMC7721 cells. Moreover, down-regulated CMTM2 could promote the invasion and migration ability of HCC cells through inducing the epithelial-mesenchymal transition (EMT) process. We further discovered that both the expression of CMTM2 and the EMT-associated marker E-cadherin were decreased in the same thirty cases of HCC tissues compared with the corresponding adjacent non-tumor tissues. Pearson correlation test showed that there was a significantly positive correlation between CMTM2 and E-cadherin in HCC tissues (P<0.05).

Conclusion

Based on the results of cell model and HCC tissues, our study suggests that down-regulated CMTM2 promotes HCC metastasis through inducing the EMT process.

Low levels of AMPK promote epithelial-mesenchymal transition in lung cancer primarily through HDAC4- and HDAC5-mediated metabolic reprogramming

AMP-activated protein kinase (AMPK) serves as a "supermetabolic regulator" that helps maintain cellular energy homeostasis. However, the role of AMPK in glucose metabolism reprogramming in lung cancer remains unclear. Here, our study shows that low AMPK expression correlates with metastasis and clinicopathologic parameters of non-small-cell lung cancer. Low AMPK significantly enhances the Warburg effect in HBE and A549 cells, which in turn induces the expression of mesenchymal markers and enhances their invasion and migration. At the mechanistic level, low AMPK up-regulates HK2 expression and glycolysis levels through HDAC4 and HDAC5. Collectively, our findings demonstrate that low AMPK-induced metabolism can promote epithelial-mesenchymal transition progression in normal bronchial epithelial cells and lung cancer cells, and increase the risk for tumour metastasis.

Catechol inhibits epidermal growth factor-induced epithelial-to-mesenchymal transition and stem cell-like properties in hepatocellular carcinoma cells

Epithelial-mesenchymal transition (EMT) is a major cellular process in which epithelial cells lose cell polarity and cell-cell adhesion and become motility and invasiveness by transforming into mesenchymal cells. Catechol is one of the natural compounds present in fruits and vegetables and has various pharmacological and physiological activities including anti-carcinogenic effects. However, the effects of catechol on EMT has not been reported. Epidermal growth factor (EGF) is one of the growth factors and is known to play a role in inducing EMT. The present study showed that catechol suppressed not only the morphological changes to the mesenchymal phenotype of epithelial HCC cells, but also the reduction of E-cadherin and the increment of Vimentin, which are typical hallmark of EMT. In addition, catechol suppressed EMT-related steps such as migration, invasion, anoikis resistance acquisition, and stem cell-like characterization through the EGFR-AKT-ERK signaling pathway during liver cancer metastasis. Therefore, these results suggest that catechol may be able to regulate the early metastasis of liver cancer in vitro.