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

Hypoxia upregulates hepatic angiopoietin-2 transcription to promote the progression of hepatocellular carcinoma

BACKGROUND

Angiopoietin-2 (Ang-2) level is related to hepatocellular carcinoma (HCC) progression. However, the dynamic expression and regulatory mechanism of Ang-2 remain unclear.

AIM

To investigate Ang-2 levels in chronic liver diseases and validate early monitoring value with a dynamic model in hepatocarcinogenesis.

METHODS

Sprague-Dawley rats in hepatocarcinogenesis were induced with diet 2-fluorenylacet-amide, and grouped based on liver histopathology by hematoxylin and eosin staining. Differently expressed genes or Ang-2 mRNA in livers were analyzed by whole-genome microarray. Ang-2 levels in chronic liver diseases were detected by an enzyme-linked immunosorbent assay.

RESULTS

Clinical observation reveled that the circulating levels of Ang-2 and hypoxia-inducible factor-1α (HIF-1α) in patients with chronic liver diseases were progressively increased from benign to HCC (P < 0.001). Dynamic model validated that the up-regulated Ang-2 in liver and blood was positively correlated with HIF-1α in hepatocarcinogenesis (P < 0.001). Mechanistically, Ang-2 was regulated by HIF-1α. When specific HIF-1α- microRNAs transfected into HCC cells, the cell proliferation significantly inhibited, HIF-1α and Ang-2 down-regulated, and also affected epithelial-mesenchymal transition via increasing E-cadherin to block cell invasion or migration with reducing of snail, twist and vimentin.

CONCLUSION

Hypoxia-induced Ang-2 up-regulating expression might serve as a sensitive early monitoring biomarker for hepatocarcinogenesis or HCC metastasis.

War or peace: Viruses and metastasis

Metastasis, the dissemination of malignant cells from a primary tumor to secondary sites, poses a catastrophic burden to cancer treatment and is the predominant cause of mortality in cancer patients. Metastasis as one of the main aspects of cancer progression could be strongly under the influence of viral infections. In fact, viruses have been central to modern cancer research and are associated with a great number of cancer cases. Viral-encoded elements are involved in modulating essential pathways or specific targets that are implicated in different stages of metastasis. Considering the continuous emergence of new viruses and the establishment of their contribution to cancer progression, the warfare between viruses and cancer appears to be endless. Here we aimed to review the critical mechanism and pathways involved in cancer metastasis and the influence of viral machinery and various routes that viruses adopt to manipulate those pathways for their benefit.

EFNA5 suppresses cell proliferation and tumor metastasis in hepatoma via epithelial-to-mesenchymal transition

BACKGROUND

EphrinA5 belongs to a subclass of ephrin ligands. Abnormal signal transduction of EFNA5 shows a relationship to the development of various tumors. In this study, we explored the level of EFNA5 in hepatoma cells and the influence of up regulation of EFNA5 expression level on the proliferation, invasion, and migration of HepG2 and LM3 cells. Additionally, this work focused on examining its possible mechanism of action, and future impacts on clinical practice.

METHODS

Immunohistochemistry was utilized to explore the connection between EFNA5 and hepatoma. Real-time quantitative polymerase chain reaction was used for determining the expression levels of EFNA5 in several hepatoma cell lines and normal hepatocytes. Cells were transfected with a pCMV3-EFNA5-flag plasmid and an EFNA5 plasmid. The expression efficiency of EFNA5 was identified through qRT-PCR. For the purpose of further identifying cell proliferation, the Cell Counting Kit-8 assay was applied. To identify changes of cell migration and invasion ability, Transwell and Boyden tests were utilized. Western blot was employed to identify the expressions mof EFNA5 and possible downstream molecules.

RESULTS

Data acquired from The Cancer Genome Atlas demonstrated that the level of EFNA5 in hepatoma was significantly downregulated in relative to the normal hepatocytes (P < 0.05). Upregulation of EFNA5 expression in hepatoma cells hindered the proliferative, invasive, and migratory ability of cells (P < 0.05). Additionally, EFNA5 downregulated the level of epithelial-mesenchymal transition-related molecules and EGFR.

CONCLUSIONS

The expression of EFNA5 was low in hepatoma cells. An increase in EFNA5 levels hinders the proliferation, invasion, and migration of hepatoma cells. These effects may occur through inhibition of hepatoma epithelial-mesenchymal transition by EFNA5. Moreover, the study on the mechanisms of proliferation, invasion and metastasis of hepatoma provides a novel theoretical basis, and may influence the clinical practice of tumor treatment in the future.

Hypoxia-induced DTL promotes the proliferation, metastasis, and sorafenib resistance of hepatocellular carcinoma through ubiquitin-mediated degradation of SLTM and subsequent Notch pathway activation

Denticleless E3 ubiquitin protein ligase homolog (DTL), the substrate receptor of the CRL4A complex, plays a central role in genome stability. Even though the oncogenic function of DTL has been investigated in several cancers, its specific role in hepatocellular carcinoma (HCC) still needs further elucidation. Data from a clinical cohort (n = 209), RNA-sequencing, and public database (TCGA and GEO) were analyzed, indicating that DTL is closely related to patient prognosis and could serve as a promising prognostic indicator in HCC. Functionally, DTL promoted the proliferation, metastasis, and sorafenib resistance of HCC in vitro. In the orthotopic tumor transplantation and tail vein injection model, DTL promoted the growth and metastasis of HCC in vivo. Mechanically, we revealed for the first time that DTL was transcriptionally activated by hypoxia-inducible factor 1α (HIF-1α) under hypoxia and functioned as a downstream effector molecule of HIF-1α. DTL promotes the ubiquitination of SAFB-like transcription modulator (SLTM) and subsequently relieves the transcriptional repression of Notch1. These results suggested that DTL may be a potential biomarker and therapeutic target for HCC.

Saponin Ⅰ from Shuitianqi () inhibits metastasis by negatively regulating the transforming growth factor-β1/Smad7 network and epithelial-mesenchymal transition in the intrahepatic metastasis Bagg's Albino/c mouse model

OBJECTIVE

To examine the influence of Saponin I from Shuitianqi (Rhizoma Schizocapasae Plantagineae) (SSPH I) on hepatocellular carcinoma (HCC) metastasis, and to elucidate the underlying mechanism.

METHODS

The intrahepatic metastasis Bagg's Albino/c (BALB/c) mouse model was established with human hepatocellular carcinomas (HepG2) cells, then treated with normal saline (once per day), cisplatin (2 mg/kg, once every 2 d), and SSPH Ⅰ (25, 50, and 75 mg/kg, once per day). Then, we assessed alterations in the hepatic pathology and target protein expressions in the intrahepatic metastasis BALB/c mouse model using a series of molecular biology techniques.

RESULTS

Based on our analysis, SSPH Ⅰ significantly alleviated hepatocyte necrosis and tumor cells infiltration. Moreover, SSPH Ⅰ suppressed extracellular matrix (ECM) degradation and angiogenesis viaa decrease in matrix etalloproteinase-2 (MMP-2), MMP-9, CD31, CD34, and vascular endothelial growth factor (VEGF) levels. Furthermore, SSPH Ⅰ repressed invasion and meta-stasis by suppressing the transforming growth factor-β1 (TGF-β1)/Smad7 axis and epithelial-mesenchymal transition (EMT), as evidenced by the scarce TGF-β1, N-cadherin, and Vimentin expressions, and elevated Smad7 and E-cadherin expressions.

CONCLUSION

The SSPH Ⅰ-mediated negative regulation of the TGF-β1/Smad7 axis and EMT are critical for the inhibition of HCC invasion and metastasis.

Pt(iv) derivatives of cisplatin and oxaliplatin bearing an EMT-related TMEM16A/COX-2-selective dual inhibitor against colorectal cancer cells HCT116

Colorectal cancer represents the over-expression of TMEM16A and COX-2, offering a promising therapeutic strategy. Two Pt(iv) conjugates derived from Pt(ii) drug (cisplatin or oxaliplatin) and niflumic acid, complexes 1 and 2, were designed and prepared to exert the positive impact of multiple biological targets of DNA/TMEM16A/COX-2 against colorectal cancer. Complex 2 afforded higher cytotoxicity than 1 and the combination of an intermediate of oxidized oxaliplatin and NFA against cancer cells A549, HeLa, MCF-7, and HCT116. Especially for colorectal cancer cells HCT116, 2 was significantly more toxic (22-fold) and selective to cancer cells against normal HUVEC cells (4-fold) than first-line oxaliplatin. The outstanding anticancer activity of 2 is partly attributed to its dramatic increase in cellular uptake, DNA damage, and apoptosis. Mechanistic studies indicated that 2 inhibited HCT116 cell metastasis by triggering TMEM16A, COX-2, and their downstream signaling pathways, including EGFR, STAT3, E-cadherin and N-cadherin.

Development of an Optimized Promoter System for Exosomal and Naked AAV Vector-Based Suicide Gene Therapy in Hepatocellular Carcinoma

Suicide gene therapy is a promising strategy for the potential treatment of hepatocellular carcinoma (HCC). However, the lack of high transduction efficiency and targeted vectors in delivering the suicide genes to only the HCC cells is a major impediment. In the present study, we utilized an adeno-associated virus serotype 6 (AAV6) and its exosomal counterpart (exo-AAV) comprising of an inducible Caspase 9 (iCasp9) gene under the control of different promoter systems for targeting HCC cells. We employed a ubiquitous cytomegalovirus immediate early enhancer/chicken β actin promoter (CAG), a liver-specific promoter (LP1), and a baculoviral IAP repeat-containing protein 5 (BIRC5) promoter for liver and cancer cell-specific expression of iCasp9, respectively. We further evaluated these vectors in Huh7 cells for their ability to kill the target cells. BIRC5 and LP1 promoter-driven iCasp9 vectors demonstrated superior cytotoxicity when compared to CAG promoter-driven iCasp9 vectors. Further validation in a murine model of HCC demonstrated that the LP1-iCasp9 or Birc5-iCasp9-based AAV6 vectors contributed to tumor regression (∼2 fold) as effectively as the AAV6-CAG-iCasp9 vectors (∼1.9 fold). Similarly, exo-AAV6 vectors showed ∼2.1 to 2.8 fold superior in vivo tumor regression when compared to mock-treated animals. Our study has developed two novel promoters (LP1 or BIRC5) whose efficacy is comparable to a strong ubiquitous promoter in both AAV and exo-AAV systems. This expands the toolkit of AAV vectors for safe and effective treatment of HCC.

Inflammatory Response in the Pathogenesis and Treatment of Hepatocellular Carcinoma: A Double-Edged Weapon

Hepatocellular carcinoma (HCC) is the most frequent among primary liver tumors (90%) and one of the main causes of cancer-related death. It develops usually in a chronically inflamed environment, ranging from compensatory parenchymal regeneration to fibrosis and cirrhosis: carcinogenesis can potentially happen in each of these stages. Inflammation determined by chronic viral infection (hepatitis B, hepatitis C, and hepatitis delta viruses) represents an important risk factor for HCC etiology through both viral direct damage and immune-related mechanisms. The deregulation of the physiological liver immunological network determined by viral infection can lead to carcinogenesis. The recent introduction of immunotherapy as the gold-standard first-line treatment for HCC highlights the role of the immune system and inflammation as a double-edged weapon in both HCC carcinogenesis and treatment. In this review we highlight how the inflammation is the key for the hepatocarcinogenesis in viral, alcohol and metabolic liver diseases.

Integrated analysis of ncRNA in hepatocellular carcinoma with CTNNB1 mutations reveals miR-205-5p and miR-3940-3p Axes

BACKGROUND

Catenin beta 1 (CTNNB1) mutations are one of the most common mutations involved in hepatocellular carcinoma (HCC) progression. However, the association between CTNNB1 mutations and HCC remains controversial.

METHODS

Five tumor samples with wild-type CTNNB1 and three tumor samples with CTNNB1 mutations were collected from patients with HCC for whole transcriptome sequencing. Selected ncRNAs and mRNAs were validated by qPCR in 48 HCC tumors. Selected ncRNA regulatory axes were verified in HCC cells by transfecting mimics and inhibitors of miRNA.

RESULTS

A network of differentially expressed (DE) lncRNA/circRNA-miRNA-mRNA was constructed to explore the effects of CTNNB1 mutations on ncRNA regulation. TXNRD1, CES1, MATN2, SERPINA5, lncRNA STAT4-210, hsa_circ_0007824, hsa_circ_0008234, hsa-miR-205-5p and hsa-miR-199a-5p were verified at the RNA expression level to validate the sequencing results. The down-up-down axes GLIS3-209/circ_0085440-miR-205-5p-GHRHR and WNK2-213-miR-3940-3p-LY6E were verified at the expression level, and proved to inhibit and promote cell proliferation, respectively.

CONCLUSION

This study demonstrated CTNNB1 mutations associated ncRNA regulatory axes playing different roles in HCC cell proliferation, providing novel insights into the controversial role of CTNNB1 in HCC.

Gastric-Type Expression Signature in Hepatocellular Carcinoma

It is known that V-set and immunoglobulin domain containing 1 (VSIG1) is a cell-cell adhesion molecule that can serve as an indicator of better survival in patients with gastric cancer. Its interaction with cytoplasmic thyroid transcription factor 1 (TTF-1) has been hypothesized to characterize gastric-type HCC, but its clinical importance is far from understood. As VSIG1 has also been supposed to be involved in the epithelial-mesenchymal transition (EMT) phenomenon, we checked for the first time in the literature the supposed interaction between VSIG1, TTF-1, and Vimentin (VIM) in HCCs. Immunohistochemical (IHC) stains were performed on 217 paraffin-embedded tissue samples that included tumor cells and normal hepatocytes, which served as positive internal controls. VSIG1 positivity was seen in 113 cases (52.07%). In 71 out of 217 HCCs (32.71%), simultaneous positivity for VSIG1 and TTF-1 was seen, being more specific for G1/G2 carcinomas with a trabecular architecture and a longer OS (p = 0.004). A negative association with VIM was revealed (p < 0.0001). Scirrhous-type HCC proved negative for all three examined markers. The present paper validates the hypothesis of the existence of a gastric-type HCC, which shows a glandular-like architecture and is characterized by double positivity for VSIG1 and TTF-1, vimentin negativity, and a significant OS.

Combined hepatocellular-cholangiocarcinoma: from genesis to molecular pathways and therapeutic strategies

Hepatocellular carcinoma (HCC) and intrahepatic cholangiocarcinoma (ICC) are the most common primary liver cancers. Little is known about the combined hepatocellular-cholangiocarcinoma (cHCC-ICC) variant and the proper therapeutic strategies. Out of over 1200 available studies about cHCC-ICC, we selected the most representative ones that reflected updated information with application to individualized therapy. Based on literature data and own experience, we hypothesize that two molecular groups of cHCC-ICC can be identified. The proposed division might have a significant therapeutic role. Most cases develop, like HCC, on a background of cirrhosis and hepatitis and share characteristics with HCC; thus, they are named HCC-type cHCC-ICC and therapeutic strategies might be like those for HCC. This review also highlights a new carcinogenic perspective and identifies, based on literature data and the own experience, a second variant of cHCC-ICC called ICC-type cHCC-ICC. Contrary to HCC, these cases show a tendency for lymph node metastases and ICC components in the metastatic tissues. No guidelines have been established yet for such cases. Individualized therapy should be, however, oriented toward the immunoprofile of the primary tumor and metastatic cells, and different therapeutic strategies should be used in patients with HCC- versus ICC-type cHCC-ICC.

Re-exploration of immunotherapy targeting EMT of hepatocellular carcinoma: Starting from the NF-κB pathway

Hepatocellular carcinoma (HCC) is the fifth most common malignancies worldwide, and its high morbidity and mortality have brought a heavy burden to the global public health system. Due to the concealment of its onset, the limitation of treatment, the acquisition of multi-drug resistance and radiation resistance, the treatment of HCC cannot achieve satisfactory results. Epithelial mesenchymal transformation (EMT) is a key process that induces progression, distant metastasis, and therapeutic resistance to a variety of malignant tumors, including HCC. Therefore, targeting EMT has become a promising tumor immunotherapy method for HCC. The NF-κB pathway is a key regulatory pathway for EMT. Targeting this pathway has shown potential to inhibit HCC infiltration, invasion, distant metastasis, and therapeutic resistance. At present, there are still some controversies about this pathway and new ideas of combined therapy, which need to be further explored. This article reviews the progress of immunotherapy in improving EMT development in HCC cells by exploring the mechanism of regulating EMT.

Cathelicidin LL-37 promotes EMT, migration and metastasis of hepatocellular carcinoma cells in vitro and mouse model

The effect of cathelicidin hCAP18/LL-37 in hepatocellular carcinoma (HCC) metastasis remains unclear. Here, we confirmed that LL-37 expression enhanced endothelial-mesenchymal transition (EMT), migration and invasion in HCC cells. And the HER2/EGFR-MAPK/ERK signal participated in the process above. More frequent lung metastases were observed in an LL-37-overexpressing hematogenous metastasis model. Interestingly, 1,25(OH)₂D₃ together with si-LL-37 significantly enhanced 1,25(OH)₂D₃-induced inhibition of migration and invasion in PLC/PRF-5 cells, and also enhanced reversion of the EMT process. Therefore, LL-37 is involved in HCC metastases, and may act as an important factor to attenuate the inhibitory activity of 1,25(OH)₂D₃ on HCC metastasis. Targeting hCAP18/LL-37 may offer a potential strategy to improve the anticancer activity of 1,25(OH)₂D₃ in HCC therapy.

Prognostic significance of programmed cell death-ligand 1 expression on immune cells and epithelial-mesenchymal transition expression in patients with hepatocellular carcinoma

Purpose

Immune checkpoint inhibitors (ICIs) have been shown significant oncological improvements in several cancers. However, ICIs are still in their infancy in hepatocellular carcinoma (HCC). Programmed cell death-ligand 1 (PD-L1), tumor-infiltrating lymphocytes (TILs), and epithelial-mesenchymal transition (EMT) have been known as prognostic factors in HCC. Therefore, we have focused on identifying the molecular mechanisms between each marker to evaluate a predictive role.

Methods

Formalin-fixed paraffin-embedded samples were obtained from 166 patients with HCC who underwent surgery. The expression of PD-L1 and TILs and EMT marker were evaluated by immunohistochemical analysis.

Results

The multivariate analysis showed that TIL expression (hazard ratio [HR], 0.483; 95% confidence interval [CI], 0.269-0.866; P = 0.015) were independent prognostic factors for overall survival. The prognostic factors for disease-free survival were EMT marker expression (HR, 1.565; 95% CI, 1.019-2.403; P = 0.005). Patients with high expression of TILs had significantly better survival compared to patients with low expression (P = 0.023). Patients who were TIL+/EMT- showed a significantly better prognosis than those who were TIL-/EMT+ (P = 0.049).

Conclusion

This study demonstrates that PD-L1 expression of TILs is closely associated with EMT marker expression in HCC. Clinical investigations using anti-PD-1/PD-L1 inhibitors in patients with EMT-associated PD-L1 upregulation are warranted.

Effect of various hepatectomy procedures on circulating tumor cells in postoperative patients: a case-matched comparative study

Background

The objective of this study is to elucidate the prevalence of systemic circulating tumor cells (CTCs) prior to and following resection of hepatocellular carcinoma (HCC), and to compare the disparities in postoperative CTCs in terms of quantity and classifications between the open liver resection (OPEN) and laparoscopic liver resection (LAP) cohorts.

Patients materials and methods

From September 2015 to May 2022, 32 consecutive HCC patients who underwent laparoscopic liver resection at Southwest Hospital were retrospectively enrolled in this study. The clinicopathological data were retrieved from a prospectively collected computer database. Patients in the OPEN group matched at a 1:1 ratio with patients who underwent open liver resection during the study period on age, gender, tumor size, number of tumors, tumor location, hepatitis B surface antigen (HBsAg) positivity, alpha-fetoprotein (AFP) level, TNM and Child-Pugh staging from the database of patients to form the control group. The Can-Patrol CTC enrichment technique was used to enrich and classify CTCS based on epithelial-mesenchymal transformation phenotypes. The endpoint was disease-free survival (DFS), and the Kaplan-Meier method and multiple Cox proportional risk model were used to analyze the influence of clinicopathological factors such as total CTCs and CTC phenotype on prognosis.

Results

The mean age of the 64 patients with primary liver cancer was 52.92 years (23-71), and 89.1% were male. The postoperative CTC clearance rate was more significant in the OPEN group. The total residual CTC and phenotypic CTC of the LAP group were significantly higher than those of the OPEN group (p = 0.017, 0.012, 0.049, and 0.030, respectively), which may increase the possibility of metastasis (p = 0.042). In Kaplan-Meier analysis, DFS was associated with several clinicopathological risk factors, including Barcelona Clinical Liver Cancer (BCLC) stage, tumor size, and vascular invasion. Of these analyses, BCLC Stage [p = 0.043, HR (95% CI) =2.03(1.022-4.034)], AFP [p = 0.007, HR (95% CI) =1.947 (1.238-3.062)], the number of positive CTCs [p = 0.004, HR (95% CI) =9.607 (2.085-44.269)] and vascular invasion [p = 0.046, HR (95% CI) =0.475 (0.22-1.023)] were significantly associated with DFS.

Conclusion

In comparison to conventional OPEN technology, LAP technology has the capacity to augment the quantity of epithelial, mixed, and mesenchymal circulating tumor cells (CTCs). Following the surgical procedure, there was a notable increase in the total CTCs, epithelial CTCs, and mixed CTCs within the LAP group, indicating a potential drawback of LAP in facilitating the release of CTCs.

Hypoxia signaling in hepatocellular carcinoma: Challenges and therapeutic opportunities

Hepatocellular carcinoma (HCC) is one of the most common cancers with a relatively high cancer-related mortality. The uncontrolled proliferation of HCC consumes a significant amount of oxygen, causing the development of a hypoxic tumor microenvironment (TME). Hypoxia-inducible factors (HIFs), crucial regulators in the TME, activate several cancer hallmarks leading to the hepatocarcinogenesis of HCC and resistance to current therapeutics. As such, HIFs and their signaling pathways have been explored as potential therapeutic targets for the future management of HCC. This review discusses the current understanding of the structure and function of HIFs and their complex relationship with the various cancer hallmarks. To address tumor hypoxia, this review provides an insight into the various potential novel therapeutic agents for managing HCC, such as hypoxia-activated prodrugs, HIF inhibitors, nanomaterials, antisense oligonucleotides, and natural compounds, that target HIFs/hypoxic signaling pathways in HCC. Because of HCC's relatively high incidence and mortality rates in the past decades, greater efforts should be put in place to explore novel therapeutic approaches to improve the outcome for HCC patients.

Tumor budding as a potential prognostic marker in determining the behavior of primary liver cancers

Hepatocellular (HCC) and intrahepatic cholangiocarcinoma (ICC), the most common primary tumors of the liver, are among the most important causes of cancer deaths worldwide. Because patients with primary liver tumors are frequently diagnosed at an advanced stage and have high mortality, many efforts have been made to identify new markers to determine their behavior and treatment, similar to those in other solid organ tumors. Recently, morphological assessment of tumor budding (TB) has been revealed as a promising prognostic finding to predict tumor behavior and survival across several different tumor types. Currently, the TB score in colorectal cancer has been revealed as an important parameter in pathology report protocols to determine the course of the disease. Regarding the liver, despite enormous data showing that many mechanisms involved in TB are associated with tumor behavior in both HCC and ICC, studies focusing on the role of TB in predicting the behavior and prognosis of these tumors have started to be investigated very recently. The purpose of this review is to present data about TB in primary tumors of the liver, pointing out the potential role of this parameter in determining the course of the disease, and emphasize the need to increase the number of further studies focusing on the evaluation of this parameter with an overview of the mechanisms involved in TB.

ASAP2 interrupts c-MET-CIN85 interaction to sustain HGF/c-MET-induced malignant potentials in hepatocellular carcinoma

BACKGROUND

Sustained activation of hepatocyte growth factor (HGF)/c-MET signaling is a major driver of hepatocellular carcinoma (HCC) progression, but underlying mechanism is unclear. ArfGAP With SH3 Domain, Ankyrin Repeat And PH Domain 2 (ASAP2) can reportedly activate GTPases and promote receptor tyrosine kinase signaling. However, the exact role of ASAP2 in HCC, especially for c-MET activation, also remains elusive.

METHODS

ASAP2 expression levels in HCC tissues and cells were quantified using qRT-PCR, western blot (WB) analysis, and immunohistochemistry staining. Cell counting kit-8 (CCK-8) and colony formation assays were performed to evaluate cell proliferation rates. Flow cytometry assays were conducted to assess apoptosis rates. Wound healing and Transwell assays were performed to determine cell migration and invasion capacities. Epithelial-mesenchymal transition (EMT)-related marker expression levels were also examined. Subcutaneous implantation and tail vein injection models were applied for in vivo growth and metastasis evaluations, respectively. Bioinformatics analyses of The Cancer Genome Atlas and STRING datasets were performed to explore ASAP2 downstream signaling. Co-immunoprecipitation and Cycloheximide chasing experiments were performed to assess protein-protein interactions and protein half-life, respectively.

RESULTS

ASAP2 had higher expression levels in HCC tissues than in normal liver, and also predicted poor prognosis. Knocking down ASAP2 significantly impaired cell proliferation, migration, and invasion capacities, but promoted apoptosis in HCC cells in vitro. However, overexpression of ASAP2 achieved the opposite effects. In vivo experiments confirmed that ASAP2 could promote HCC cell growth and facilitate lung metastasis. Interestingly, ASAP2 was essential for triggering EMT. Gene Set Enrichment Analysis demonstrated that c-MET signaling was greatly enriched in ASAP2-high HCC cases. Additionally, c-MET signaling activity was significantly decreased following ASAP knockdown, evidenced by reduced c-MET, p-AKT, and p-ERK1/2 protein levels. Importantly, ASAP2 knockdown effectively attenuated HGF/c-MET signaling-induced malignant phenotypes. c-MET and ASAP2 expression levels were positively correlated in our cohort. Mechanistically, ASAP2 can directly bind to CIN85, thereby disrupting its interaction with c-MET, and can thus antagonize CIN85-induced c-MET internalization and lysosome-mediated degradation. Notably, knocking down CIN85 can rescue the observed inhibitory effects caused by ASAP2 knockdown.

CONCLUSIONS

This study highlights the importance of ASAP2 in sustaining c-MET signaling, which can facilitate HCC progression.

SAMD9 Promotes Postoperative Recurrence of Esophageal Squamous Cell Carcinoma by Stimulating MYH9-Mediated GSK3β/β-Catenin Signaling

Recurrence is a challenge to survival after the initial treatment of esophageal squamous cell carcinoma (ESCC). But, its mechanism remains elusive and there are currently no biomarkers to predict postoperative recurrence. Here, the possibility of sterile alpha motif domain-containing protein 9 (SAMD9) as a predictor of postoperative recurrence of ESCC is evaluated and the molecular mechanisms by which SAMD9 promotes ESCC recurrence are elucidated. The authors found that the high level of SAMD9 is correlated with postoperative recurrence and poor prognosis of ESCC. Overexpression of SAMD9 promotes tumor stemness, angiogenesis, and EMT, while downregulation of SAMD9 reduced these phenotypes. Mechanistically, it is found that SAMD9 stimulated ubiquitination-mediated glycogen synthase kinase-3 beta (GSK-3β) degradation by interaction with myosin-9 (MYH9) and TNF receptor-associated factor 6 (TRAF6), which in turn activated Wnt/β-catenin pathway. Further, the authors demonstrated that silencing SAMD9 inhibited lung metastasis and tumor formation in vivo. Finally, the authors found that silencing MYH9 or β-catenin, or overexpressing GSK-3β inhibited SAMD9-stimulated ESCC cell stemness, EMT, angiogenesis, metastasis, and tumorigenicity. Together, the findings indicate that the SAMD9/MYH9/GSK3β/β-catenin axis promotes ESCC postoperative recurrence and that SAMD9 is a crucial target for ESCC therapy. Additionally, SAMD9 has the potential as a predictor of postoperative recurrence in ESCC.

The role of N-glycosylation modification in the pathogenesis of liver cancer

N-glycosylation is one of the most common types of protein modifications and it plays a vital role in normal physiological processes. However, aberrant N-glycan modifications are closely associated with the pathogenesis of diverse diseases, including processes such as malignant transformation and tumor progression. It is known that the N-glycan conformation of the associated glycoproteins is altered during different stages of hepatocarcinogenesis. Characterizing the heterogeneity and biological functions of glycans in liver cancer patients will facilitate a deeper understanding of the molecular mechanisms of liver injury and hepatocarcinogenesis. In this article, we review the role of N-glycosylation in hepatocarcinogenesis, focusing on epithelial-mesenchymal transition, extracellular matrix changes, and tumor microenvironment formation. We highlight the role of N-glycosylation in the pathogenesis of liver cancer and its potential applications in the treatment or diagnosis of liver cancer.

The role of N-glycosylation modification in the pathogenesis of liver cancer

N-glycosylation is one of the most common types of protein modifications and it plays a vital role in normal physiological processes. However, aberrant N-glycan modifications are closely associated with the pathogenesis of diverse diseases, including processes such as malignant transformation and tumor progression. It is known that the N-glycan conformation of the associated glycoproteins is altered during different stages of hepatocarcinogenesis. Characterizing the heterogeneity and biological functions of glycans in liver cancer patients will facilitate a deeper understanding of the molecular mechanisms of liver injury and hepatocarcinogenesis. In this article, we review the role of N-glycosylation in hepatocarcinogenesis, focusing on epithelial-mesenchymal transition, extracellular matrix changes, and tumor microenvironment formation. We highlight the role of N-glycosylation in the pathogenesis of liver cancer and its potential applications in the treatment or diagnosis of liver cancer.

Microtubule-associated protein 4 promotes epithelial mesenchymal transition in hepatocellular cancer cells via regulating GSK3β/β-catenin pathway

Metastasis is a major obstacle in the treatment of hepatocellular carcinoma (HCC). Microtubule-associated protein 4 (MAP4) plays an important role as a coordinator between microtubules and microfilaments. However, the role of MAP4 in HCC migration and epithelial mesenchymal transition (EMT) is unclear. We compared the protein and mRNA levels of MAP4 in human HCC and adjacent normal tissues using western blotting, immunohistochemistry and RT-qPCR. The migration and invasion abilities and the levels of EMT markers (E-Cadherin, N-Cadherin, Vimentin, and Snail) were compared between MAP4-knockdown and MAP4-overexpressed HCC cells. Finally, we examined whether β-catenin and glycogen synthase kinase 3β (GSK3β) are involved in the stimulatory effects of MAP4 on HCC migration, invasion and EMT. The results revealed that MAP4 levels were higher in the HCC tissues than in the normal hepatic tissues. More importantly, MAP4 knockdown suppressed migration and invasion abilities and EMT processes in HCC cells, which were confirmed by the stimulatory effects of MAP4 overexpression on EMT processes in HCC cells. Further evidence demonstrated that the up-regulation of β-catenin activity induced by the interaction between MAP4 and GSK3β possibly accounted for the pro-migration and pro-EMT effects of MAP4 on HCC cells. Taken together, these results suggest that MAP4 promotes migration, invasion, and EMT in HCC cells by regulating the GSK3β/β-catenin pathway.

Roles of conventional and complementary therapies in recurrent hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the fifth most common type of cancer and the fourth leading cause of cancer-related deaths in the world. HCC has a reported recurrence rate of 70%-80% after 5 years of follow-up. Controlling tumor recurrence is the most critical factor associated with HCC mortality. Conventional salvage therapies for recurrent HCC include re-hepatectomy or liver transplantation, transcatheter arterial chemoembolization, Y-90, target therapy, and immunotherapy; however, these conventional treatment modalities have yet to achieve consistently favorable outcomes. Meanwhile, previous studies have demonstrated that conventional therapies in combination with traditional Chinese medicine (TCM), acupuncture, moxibustion or dietary supplements could notably benefit patients with HCC recurrence by strengthening and augmenting the overall management strategy. However, systemic reviews related to the interactions between complementary therapies and conventional therapy in recurrent HCC are limited. In this review, we discuss the molecular mechanisms underlying the functions of complementary therapies for recurrent HCC, which include augmenting the local control to improve the congestion status of primary tumors and reducing multicentric tumor occurrence via inducing autophagy, apoptosis or cell cycle arrest. TCM and its derivatives may play important roles in helping to control HCC recurrence by inhibiting epithelial-mesenchymal transition, migration, invasion, and metastasis, inhibiting cancer stem cells, and ameliorating drug resistance.

V-set and immunoglobulin domain containing 1 (VSIG1) as an emerging target for epithelial-mesenchymal transition of gastric cancer

V-set and Immunoglobulin domain containing 1 (VSIG1) is a cell–cell adhesion molecule which role in the genesis and evolution of gastric cancer (GC) is not understood. Only three Medline-indexed papers have focused on the role of VSIG1 in GC. The clinicopathological features of 94 GCs were examined in association with immunohistochemical (IHC) patterns of VSIG1, E-cadherin, and β-catenin which were assessed in the tumor core (central) vs. invasive edge. Cases were classified depending on the VSIG1 expression: membrane/membrane in both core and invasive front; null/negative staining in both core and invasive front; and cases with translocational patterns: membrane core/cytoplasmic buds and cytoplasmic core/null buds. Most of the tumors showed null pattern (n = 54). Cases with translocational patterns (n = 20) were GCs with a high lymph node ratio value (≥ 0.26) and advanced Dukes-MAC-like stage. Of the 20 total cases, 9 showed membrane-to-nuclear translocation of β-catenin and loss of E-cadherin, as indicators of epithelial–mesenchymal transition. All cases with membrane/membrane pattern (n = 20) involved the distal stomach. The poorest overall survival was registered in patients with subcellular translocation of VSIG1, compared to those with either membrane/membrane or null patterns (p = 0.002). In GC, VSIG1 acts as an adhesion membrane protein but its membrane-cytoplasmic translocation can be an indicator of epithelial–mesenchymal transition due to cytoplasmic VSIG1-mediated activation of canonical Wnt/β-catenin signaling pathway.

Involvement of microRNAs and their potential diagnostic, therapeutic, and prognostic role in hepatocellular carcinoma

BACKGROUND

Hepatocellular carcinoma (HCC) accounts for 85%-90% of primary liver cancer. MicroRNAs (miRNAs) are small non-coding RNAs that regulate gene expression by targeting the 3'UTR of mRNA. Abnormal expression and regulation of miRNAs are involved in the occurrence and progression of HCC, and miRNAs can also play a role in the diagnosis and treatment of HCC as oncogenes or tumor suppressors.

METHODS

In the past decades, a large number of studies have shown that miRNAs play an essential regulatory role in HCC and have potential as biomarkers for HCC. We reviewed the literature to summarize these studies.

RESULTS

By reviewing the literature, we retrospected the roles of miRNAs in the development, diagnosis, treatment, and prognosis of HCC, and put forward prospects for the further research on miRNAs in the precision treatment of HCC.

CONCLUSION

MicroRNAs are important regulators and biomarkers in the occurrence, progression, outcome, and treatment of HCC, and can provide new targets and strategies for improving the therapeutic effect of HCC.

Assessment of the TGFB1 gene expression and methylation status of the promoter region in patients with colorectal cancer

The aim of this study was to evaluate the expression of the TGFB1 gene encoding the TGF-β1 cytokine in 64 patients, and then to compare it with clinico-pathological features. The study also investigated whether the regulation of the gene expression is caused by methylation of the promoter region between - 235 and + 22 nucleotide from the start of transcription. The dependence of the relative level of the TGFB1 gene expression on the clinical advancement according to the TNM classifications was shown. Additionally, the individual grades of the T and M features of the TNM classification differed in the relative transcript levels of the TGFB1 gene. Moreover, the higher relative expression level of the studied gene was associated with a lack of vascular invasion by cancer cells and presence of lymphocytes in the neoplastic tissue. The obtained results may indicate a possible impact of the gene on the process of carcinogenesis in colorectal cancer and reduction of its expression level may be one of the factors contributing to progression of the disease.

Pseudogene PLGLA exerts anti-tumor effects on hepatocellular carcinoma through modulating miR-324-3p/GLYATL1 axis

BACKGROUND

Pseudogenes are dysfunctional copies of protein-coding genes that showed critical regulatory roles during carcinogenesis. Plasminogen like A (PLGLA) is a transcribed unprocessed pseudogene and biasedly expressed in liver. But its function has not been studied in hepatocellular carcinoma (HCC).

AIMS

We aimed to explore the role of PLGLA in HCC.

METHODS

The expression of PLGLA and its association with pathological features in HCC patients was analyzed using The Cancer Genome Atlas (TCGA) datasets. Quantitative reverse transcription PCR (qRT-PCR) was used to validate PLGLA level in HCC tissue samples and cell lines. Gain-of-function experiments in vitro and in vivo were employed to assess the impact of PLGLA on HCC cell proliferation, migration and invasion. Luciferase reporter assay and RNA pull-down assay were conducted to confirm the interaction among PLGLA, miR-324-3p and GLYATL1.

RESULTS

PLGLA expression was significantly downregulated in HCC tissues and cell lines. Furthermore, low PLGLA expression was positively associated with tumor progression and poor prognosis. PLGLA restoration markedly suppressed cell proliferation, migration and invasion. Mechanistically, PLGLA could competitively bind to miR-324-3p and acted as a competitive endogenous RNA (ceRNA) to enhance GLYATL1 expression.

CONCLUSIONS

Our results established a novel tumor suppressive role of PLGLA in HCC pathogenesis and highlighted its potential as a therapeutic target for HCC treatment.

Exosomal miR-4800-3p Aggravates the Progression of Hepatocellular Carcinoma via Regulating the Hippo Signaling Pathway by Targeting STK25

Background

Emerging evidence has shown that exosome microRNAs (miRNAs) regulate the development of hepatocellular carcinoma (HCC). Here, the influences of miR-4800-3p on the progression of HCC were explored.

Materials and Methods

The expression of miR-4800-3p in the exosome derived by transforming growth factor beta 1 (TGF-β1)-treated HCC cells and the serum exosome isolated from HCC patients were identified by real-time PCR. The effects of TGF-β1 and the influences of Huh7-secreted exosomes and the effects of miR-4800-3p combined with/without STK25 on cell functions were explored using the EdU assay cloning experiments, wound healing assay, and Transwell assay. The corresponding molecular mechanisms were further detected using Western blot and real-time PCR assays. The combination of miR-4800-3p and STK25 was verified by the dual-luciferase and RNA pulldown assays. The influences of miR-4800-3p on the growth and epithelial–mesenchymal transformation (EMT) of implanted tumors were tested in vivo and further confirmed by Western blot.

Results

The miR-4800-3p expression was highly expressed in both exosomes derived by TGF-β1-treated HCC cells and the serum exosomes of HCC patients. In the cases of treatment with both Huh7-derived exosomes, the level of miR-4800-3p expression was highest, and the treatment of TGF-β1 could greatly promote the proliferation, stemness, migration, and invasion of HCC cells via upregulating the markers of stemness and EMT, including CD44, CD133, OCT4, N-cadherin, E-cadherin, and ZO-1. Similar results could be obtained when miR-4800-3p was overexpressed in HCC cells. Furthermore, downregulation of STK25 expression, a direct target gene of miR-4800-3p, could greatly rescue the malignant biological behaviors aggravated by overexpression of miR-4800-3p. This was achieved by suppressing the expression of CD44, CD133, OCT4, N-cadherin, and PCNA and activating the Hippo pathway while increasing E-cadherin and ZO-1. Similar results were also obtained in vivo that knockdown of miR-4800-3p expression suppressed tumor growth induced by Huh7-derived exosomes by mediating the EMT markers and the Hippo signaling pathway.

Conclusion

Exosomal miR-4800-3p could accelerate HCC development by regulating the Hippo signal by targeting STK25, which could be used as a new therapeutic target for HCC treatment.

High CBX8 Expression Leads to Poor Prognosis in Laryngeal Squamous Cell Carcinoma by Inducing EMT by Activating the Wnt/β-Catenin Signaling Pathway

Background

In this study, we detected the expression of chromobox protein homolog 8 (CBX8) in laryngeal squamous cell carcinoma (LSCC) and its influence on the occurrence and progression of LSCC.

Methods

Pancancer analysis of CBX8 was analyzed by TCGA database and its expression in LSCC.The expression of CBX8 in 30 pairs of LSCC and adjacent tissues was analyzed by quantitative real-time PCR(qRT-PCR)and immunohistochemical assays, and its association with the prognosis and clinicopathological features of LSCC was further evaluated. A CBX8 knockdown model was constructed in AMC-HN-8 and Hep2 cell lines. The effects of CBX8 on LSCC cell proliferation, migration, invasion and apoptosis were detected by CCK8,EdU,wound healing, Transwell and flow cytometry assays. Levels of apoptosis-related protein, WNT/β-catenin signaling pathway and epithelial to mesenchymal transition (EMT) proteins, including Bax, Bcl2, β-catenin, DKK1, GSK3β, N-cadherin, E-cadherin and Snail1, in LSCC cells were detected by Western blotting.

Results

CBX8 was overexpressed in LSCC. High expression of CBX8 in LSCC patients led to shorter overall survival and correlated with tumor stage and lymphatic metastasis. After CBX8 knockdown, the proliferation of AMC-HN-8 and Hep2 cells slowed, and the number of EdU-positive cells decreased. Wound healing slowed down, and the number of Transwell invading cells decreased. The percentage of apoptotic cells increased. The expression levels of Bcl2, β-catenin, N-cadherin and Snail11 proteins were significantly reduced in the CBX8 knockdown cells, while Bax, DKK1, GSK3β and E-cadherin significantly increased with their corresponding controls.

Conclusion

CBX8 is highly expressed in LSCC and induces the EMT process by activating the Wnt/β-catenin signaling pathway to promote LSCC cell proliferation and migration and inhibit apoptosis, resulting in poor prognosis.

Effects of dihydroartemisinin combined with cisplatin on proliferation, apoptosis and migration of HepG2 cells

Cisplatin (DDP) is a potent and widely applied chemotherapeutic agent. However, its clinical efficacy for the treatment of liver cancer is limited by adverse effects and the development of resistance. Combinatorial therapy may alleviate these issues. Dihydroartemisinin (DHA) is a first-generation derivative of artemisinin. The effects of DDP on liver cancer when applied in combination with DHA have not previously been studied. Therefore, the present study aimed to investigate the effects of DHA combined with DDP on HepG2 cells and their potential underlying molecular mechanisms. HepG2 cells were treated with different concentrations of DHA and/or DDP. Cell Counting Kit-8 assay was used to assess the cell viability. Cell proliferation and apoptosis were quantified using flow cytometry, acridine orange/ethidium bromide (AO/EB) fluorescent dual staining and the colony formation assay. Cell migration was quantified using the Transwell and wound healing assays. The HepG2 cell protein expression levels of Fas, Fas-associated death domain (FADD), procaspase-3, cleaved caspase-3, pro-caspase-8, cleaved caspase-8, Bax, Bcl-2, E-cadherin and N-cadherin, were detected via western blotting. Gelatin zymography was used to assess the levels of MMP-9 secreted by HepG2 cells into the supernatant. Following combined DHA and DDP treatment, the percentage of apoptotic cells was significantly increased, whereas cell proliferation and migration were significantly reduced, compared with cells treated with DDP only. DHA and DPP in combination significantly inhibited the expression of MMP-9, significantly increased the protein expression levels of Fas, FADD, Bax and E-cadherin, significantly increased the ratio of cleaved caspase-3 and cleaved caspase-8 to their precursor proteins and significantly decreased the protein expression levels of Bcl-2 and N-cadherin. The findings of the present study suggested that, DHA may confer synergistic effects with DDP in potentially promoting apoptosis and inhibiting the epithelial-mesenchymal transition for the treatment of liver cancer.

The inhibitory effect of LINC00261 upregulation on the pancreatic cancer EMT process is mediated by KLF13 via the mTOR signaling pathway

PURPOSE

The long noncoding RNA LINC00261 was reported to be involved in carcinogenesis and has been validated as a tumor suppressor in pancreatic cancer (PC); however, how LINC00261 is regulated has not been fully examined. Here, we attempted to investigate the upstream and downstream targets of LINC00261 in PC.

METHODS

LINC00261 expression in PC tissues was examined by the Gene Expression Omnibus (GEO) datasets and the Gene Expression Profiling Interactive Analysis (GEPIA) database. The quantitative reverse transcription polymerase chain reaction (qRT-PCR) assays were performed to detect the expression level of LINC00261 in PC cells. The location of LINC00261 in PC cells was identified by RNA fluorescence in situ hybridization (RNA-FISH). Cell Counting Kit-8 (CCK-8), cell apoptosis assay, transwell invasion and migration assays testified the critical role of LINC00261 in PC. The luciferase reporter assay was applied to confirm the binding of LINC00261 to its upstream transcription factor KLF13. The changes in LINC00261 related target protein levels were analyzed by Western blotting assay.

RESULTS

LINC00261 was significantly lower in PC tissues and was mainly concentrated in the nucleus. Overexpression of LINC00261 inhibited the invasion and migration of PC cells. Mechanistically, transcription factor KLF13 was confirmed to inhibit the epithelial-mesenchymal transition (EMT) process of PC cells by promoting the transcription of LINC00261 and suppressing the expression of metastasis-associated proteins, such as matrix metalloproteinase MMP2 and vimentin, thus inhibiting the metastasis of PC.

CONCLUSION

LINC00261 regulates PC cell metastasis through the "KLF13-LINC00261-mTOR-P70S6K1-S6" signaling pathway, which provides a significant set of potential PC therapeutic targets.

Nonpolypous Hamartomas of the Gastrointestinal Tract: An Updated Review on Classification, Denominations, and Clinical Management

Purpose

To perform the first systematic report about histological subtypes of nonpolypous hamartomas of the gastrointestinal (GI) tract, from esophagus to anal canal.

Design

From over 19,000 studies about hamartomas, most of them published as case series or case presentations, we have selected the most representative ones for the GI tract, excluding polyposis syndromes. To have a whole picture of these hamartomas, all of the data were combined with the personal experience of the authors who are GI pathologists.

Results

The examined articles showed predominance of vascular and combined vascular and mesenchymal hamartomas. Arteriovenous hamartomas or Brunner gland hamartomas are mainly diagnosed in the small intestine, with preponderance for duodenum. Other malformations such cavernous hamartomas are more specific for the colorectal segments, whereas chondromatous hamartomas or those derived from the neural ectoderm were mostly reported in the esophagus. As newly recognized entities were admitted in the last years, misdiagnosis is frequent, and the best therapeutic approach is far to be known.

Conclusion

Even rare, hamartomas of the GI tract need to be differentiated from tumors and familial polyposis syndromes. Knowing their proper denominations and possible complications is valuable for gastroenterologists, pathologists, and surgeons, to be aware in the differential diagnosis.

Iodine-125 Seeds Inhibit Carcinogenesis of Hepatocellular Carcinoma Cells by Suppressing Epithelial-Mesenchymal Transition via TGF-β1/Smad Signaling

To investigate the radioactive iodine-125 (I-125) seed on migrating and invading of hepatocellular carcinoma (HCC) cells and its mechanism, the irradiation of PLC and Huh7 cells was carried out with I-125 seeds in vitro. Cell counting kit 8 assay was employed to measure cell viability. Cell migration was evaluated by using wound-healing assay. Cell invasion was detected by Transwell assay; RT-PCR and Western blot were used for the detection of the mRNA and proteins of TGF-β1 signaling pathway-related genes. The viability of PLC and Huh7 cells declined in a dose-dependent manner with increasing irradiation from 0 Gy, 2 Gy, 4 Gy, and 6 Gy, to 8 Gy, respectively. The IC50 of PLC and Huh7 cells were 6.20 Gy and 5.39 Gy, respectively, after 24 h of irradiation. Migration and invasion abilities of I-125 group cells were greatly weakened (P < 0.05) comparing with the control group. According to the outcomes of RT-PCR and WB, I-125 seed irradiation significantly inhibited the mRNA and protein expression of N-cadherin, vimentin, TGF-β1, p-Smad2/3, and Snail. But the mRNA and protein expressions of E-cadherin were enhanced. Rescue experiment demonstrates that TGF-β1 activator could reverse the inhibitory effects of I-125 on invasion and migration of cells. The results of in vivo experiments further verified that the I-125 seeds can inhibit the proliferation and TGF-β1 of xenographed PLC cells. In conclusion, I-125 seeds restrain the invasion and migration of HCC cells by suppressing epithelial to mesenchymal transition, which may associate with the inhibition of the TGF-β1 signaling.

Lysophosphatidylcholine acyltransferase 1 promotes epithelial-mesenchymal transition of hepatocellular carcinoma via the Wnt/β-catenin signaling pathway

INTRODUCTION AND OBJECTIVES

Hepatocellular carcinoma (HCC) is one of the most malignant digestive tumors, and its insidious onset and rapid progression are the main reasons for the difficulty in effective treatment. Lysophosphatidylcholine acyltransferase 1 (LPCAT1) is a key enzyme that regulates phospholipid metabolism of the cell membrane. However, the mechanism by which LPCAT1 regulates HCC metastasis remains unknown. This study aimed to explore its biological function and potential mechanisms concerning migration and invasion in HCC.

MATERIALS AND METHODS

LPCAT1 expression in HCC tissues and its association with clinical outcomes were investigated by western blotting and bioinformatic methods, respectively. The role of LPCAT1 in migration and invasion was assessed via Transwell assays. The expression pattern of epithelial-mesenchymal transition (EMT) markers was quantified by western blotting. The biological behaviors of LPCAT1 in vivo were evaluated using xenograft tumor models and caudal vein metastatic models. Signaling pathways related to LPCAT1 were predicted using gene set enrichment analysis (GSEA) and further confirmed by western blotting.

RESULTS

LPCAT1 expression was significantly upregulated in HCC tissues and indicated a poor prognosis of HCC patients. Several EMT-related markers were found to be regulated by LPCAT1. HCC cells overexpressing LPCAT1 exhibited remarkably high migration and invasion capacities, upregulated expression of mesenchymal markers and reduced E-cadherin expression. In vivo, LPCAT1 promoted HCC pulmonary metastasis. Furthermore, the Wnt/β-catenin signaling pathway was confirmed to be activated by LPCAT1.

CONCLUSIONS

LPCAT1 could serve as a promising biomarker of HCC and as a novel therapeutic target for the treatment of metastatic HCC.

Molecular Mechanisms of Resistance to Tyrosine Kinase Inhibitors Associated with Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is the second leading cause of cancer-related death, which can be attributed to the high incidence and first diagnosis at an advanced stage. Tyrosine kinase inhibitors (TKIs), a class of small-molecule targeting drugs, are primarily used for the clinical treatment of HCC after chemotherapy because they show significant clinical efficacy and low incidence of clinical adverse reactions. However, resistance to sorafenib and other TKIs, which can be used to treat advanced HCC, poses a significant challenge. Recent mechanistic studies have shown that epithelial-mesenchymal transition or transformation (EMT), ATP binding cassette (ABC) transporters, hypoxia, autophagy, and angiogenesis are involved in apoptosis, angiogenesis, HCC cell proliferation, and TKI resistance in patients with HCC. Exploring and overcoming such resistance mechanisms is essential to extend the therapeutic benefits of TKIs to patients with TKI-resistant HCC. This review aims to summarize the potential resistance mechanism proposed in recent years and methods to reverse TKI resistance in the context of HCC.

Circular RNA circ SET domain containing 2 (circSETD2) inhibits hepatocellular carcinoma cell proliferation and invasion in vivo and in vitro

Liver cancer is a common malignant tumor with high incidence and mortality rates. However, a reliable prognostic signature has not yet been confirmed. Circular RNAs (circRNAs) play a role in the development and prognosis of numerous malignancies as well as liver cancer. Therefore, identifying abnormally expressed circRNAs in liver cancer tissue is essential for early diagnosis and treatment. This study found that circular RNA circ SET domain containing 2 (circSETD2) is abnormally expressed in liver cancer tissues, but the role and molecular mechanismsin the occurrence and development of liver cancer are still unclear. The expression level of circSETD2 was evaluated through Quantitative Real-time Polymerase chain reaction (qRT-PCR) in cancerous liver tissues (30 cases), liver cancer cell lines and para-cancerous tissues. Knockdown and overexpression circSETD2 lentiviral vector was constructed and applied to transfect hepatoma cells. Cell Counting Kit-8 (CCK-8), colony formation assay, flow cytometry and Transwell assay were used to examine the effects of circSETD2 overexpression or knockdown on liver cancer migration, invasion, cell cycle and cell proliferation. The tumourigenicity in vivo was utilized to assess the effect of circSETD2 on the proliferation of liver cancer cells. circSETD2 expression is lower in cell lines and liver cancer tissues. circSETD2 knockdown can considerably increase liver cancer cells’ invasion, proliferation and colony formation. While In vitro and in vivo, circSETD2 overexpression shows opposite effect. Western blot showed that circSETD2 knockdown can considerably promote E-cadherin expression and inhibit Vimentin, N-cadherin, matrix metallopeptidase-9 (MMP-9) and MMP-2 expression. These findings improve our understanding of the mechanisms of liver cancer progression and will guide future development of therapeutic strategies against the disease by targeting circ-SETD2.

The clinical relevance of epithelial-mesenchymal transition and its correlations with tumorigenic immune infiltrates in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a cancer with extremely high mortality. Epithelial-mesenchymal transition (EMT) may play an important role in the occurrence, invasion, and prognosis of HCC; however, its relationship with immunity in HCC has not yet been studied. Therefore, we investigated the diagnostic and prognostic values of EMT and explored its potential connections with tumorigenic immune infiltrates in HCC. We first proposed a quantitative metric of EMT activity, the EMT score. After applying this metric to 20 datasets from the Integrative Molecular Database of Hepatocellular Carcinoma, The Cancer Genome Atlas, and the Gene Expression Omnibus, we explored the ability of the EMT score to stratify across sample types. We then applied the EMT score for survival analysis and to differentiate patients with/without vascular invasion to test its prognostic value. We also collected and calculated data on the abundance of immune cells and immune cell markers in HCC and investigated their correlations with EMT scores. Finally, we synthesized and analyzed 20 datasets and constructed an EMT-gene-immune linkage network. The results showed higher EMT scores in HCC samples than in cirrhotic and normal livers. The cases with higher EMT scores also showed poorer performance in terms of prognostic factors such as vascular invasion and overall survival time. Our research demonstrated a broad correlation between EMT and the tumor immune microenvironment, and we uncovered multiple potential linkers associated with both EMT and immunity. Studying EMT has clinical relevance and high diagnostic and prognostic value for HCC.

Comprehensive Analysis of the Expression and Clinical Significance of THO Complex Members in Hepatocellular Carcinoma

Background

Methods

Results

Conclusion

Transglutaminase 3 expression in hepatocellular carcinoma patients: Correlation with tumor features and survival profile

BACKGROUND

Transglutaminase 3 (TGM3) regulates multiple oncogene pathways (GSK-3β/β-catenin pathway, Akt/ERK pathway, etc.) to promote hepatocellular carcinoma (HCC) cell proliferation, migration and invasion, however, its clinical value for HCC management is still limited. Therefore, we conducted this study to compare the TGM3 expression between tumor tissue and paired adjacent noncancerous tissue, aiming to explore the clinical application of TGM3 in HCC patients.

METHODS

Totally, 208 HCC patients were enrolled and their clinicopathological features were collected. Then, 208 pairs of HCC specimens and adjacent noncancerous specimens were used to detect TGM3 protein expression by IHC assay and assessed by a semi-quantitative scoring method. Besides, 157 pairs were proposed to detect TGM3 mRNA expression by RT-qPCR.

RESULTS

Both TGM3 protein (P<0.001) and mRNA (P<0.001) levels were increased in HCC specimens compared to adjacent noncancerous specimens. Besides, TGM3 high protein expression correlated with multifocal tumor nodules (P<0.001), advanced Barcelona Clinic Liver Cancer (BCLC) stage (P = 0.006), higher carcinoembryonic antigen (P = 0.038) and alpha-fetoprotein (AFP) (P<0.001). While TGM3 high mRNA expression correlated with multifocal tumor nodules (P = 0.025), largest tumor size ≥ 5.0 cm (P = 0.042) and higher AFP (P = 0.019). Furthermore, both TGM3 protein (P = 0.002) and mRNA (P = 0.028) high expressions correlated with shorter overall survival (OS). While after adjustment by multivariant Cox's regression, TGM3 protein high expression (vs. low) independently predicted worse OS (P = 0.004).

CONCLUSIONS

TMG3 expression is increased in tumor tissue, also its high expression correlates with multiple tumor nodules, higher BCLC stage, abnormal AFP and reduced OS in HCC patients.

Exosomes in Pathogenesis, Diagnosis, and Treatment of Hepatocellular Carcinoma

Exosomes are extracellular vesicles with a diameter of 30-150 nm that are released by most types of cells and have been confirmed to be involved in many physical and pathological processes, especially in cell to cell communication. Compared with other vesicles, exosomes have a unique double-layer saclike structure that allows them to be present stably in various body fluids, including blood, cerebrospinal fluid, urine, saliva, and serous cavity effusion. The cargoes of exosomes reflect the characteristics of host cells. Due to the nature of hepatocellular carcinoma (HCC) cells, heterogeneity in the bioactive substances usually exist in exosomes. In addition, exosomes can efficiently deliver cargoes to the target cells to exert pathological functions, playing important role in tumor occurrence, development, metastasis, immune regulation, and drug resistance. Previous studies have been shown that exosomes have wide applications in diagnosis and treatment of HCC. In this review, we discuss these recent findings and highlight the significant roles of exosomes in HCC, focusing on the effect and underlying mechanisms of exosomes to regulate HCC progression and the potential clinical value of exosomes as biomarkers and therapeutic targets.

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.