Naa20, the catalytic subunit of NatB complex, contributes to hepatocellular carcinoma by regulating the LKB1–AMPK–mTOR axis

AbstractN-α-acetyltransferase 20 (Naa20), which is a catalytic subunit of the N-terminal acetyltransferase B (NatB) complex, has recently been reported to be implicated in hepatocellular carcinoma (HCC) progression and autophagy, but the underlying mechanism remains unclear. Here, we report that based on bioinformatic analysis of Gene Expression Omnibus and The Cancer Genome Atlas data sets, Naa20 expression is much higher in HCC tumors than in normal tissues, promoting oncogenic properties in HCC cells. Mechanistically, Naa20 inhibits the activity of AMP-activated protein kinase (AMPK) to promote the mammalian target of rapamycin signaling pathway, which contributes to cell proliferation, as well as autophagy, through its N-terminal acetyltransferase (NAT) activity. We further show that liver kinase B1 (LKB1), a major regulator of AMPK activity, can be N-terminally acetylated by NatB in vitro, but also probably by NatB and/or other members of the NAT family in vivo, which may have a negative effect on AMPK activity through downregulation of LKB1 phosphorylation at S428. Indeed, p-LKB1 (S428) and p-AMPK levels are enhanced in Naa20-deficient cells, as well as in cells expressing the nonacetylated LKB1-MPE mutant; moreover, importantly, LKB1 deficiency reverses the molecular and cellular events driven by Naa20 knockdown. Taken together, our findings suggest that N-terminal acetylation of LKB1 by Naa20 may inhibit the LKB1–AMPK signaling pathway, which contributes to tumorigenesis and autophagy in HCC.

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Sirt1 deacetylates and stabilizes p62 to promote hepato-carcinogenesis

Cell Death and Disease ◽

10.1038/s41419-021-03666-z ◽

2021 ◽

Vol 12 (4) ◽

Author(s):

Lifeng Feng ◽

Miaoqin Chen ◽

Yiling Li ◽

Muchun Li ◽

Shiman Hu ◽

...

Keyword(s):

Hepatocellular Carcinoma ◽

Overall Survival ◽

Cell Growth ◽

Knockout Mice ◽

Liver Tumors ◽

Underlying Mechanism ◽

Carcinoma Cells ◽

Conditional Knockout

Abstractp62/SQSTM1 is frequently up-regulated in many cancers including hepatocellular carcinoma. Highly expressed p62 promotes hepato-carcinogenesis by activating many signaling pathways including Nrf2, mTORC1, and NFκB signaling. However, the underlying mechanism for p62 up-regulation in hepatocellular carcinoma remains largely unclear. Herein, we confirmed that p62 was up-regulated in hepatocellular carcinoma and its higher expression was associated with shorter overall survival in patients. The knockdown of p62 in hepatocellular carcinoma cells decreased cell growth in vitro and in vivo. Intriguingly, p62 protein stability could be reduced by its acetylation at lysine 295, which was regulated by deacetylase Sirt1 and acetyltransferase GCN5. Acetylated p62 increased its association with the E3 ligase Keap1, which facilitated its poly-ubiquitination-dependent proteasomal degradation. Moreover, Sirt1 was up-regulated to deacetylate and stabilize p62 in hepatocellular carcinoma. Additionally, Hepatocyte Sirt1 conditional knockout mice developed much fewer liver tumors after Diethynitrosamine treatment, which could be reversed by the re-introduction of exogenous p62. Taken together, Sirt1 deacetylates p62 at lysine 295 to disturb Keap1-mediated p62 poly-ubiquitination, thus up-regulating p62 expression to promote hepato-carcinogenesis. Therefore, targeting Sirt1 or p62 is a reasonable strategy for the treatment of hepatocellular carcinoma.

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Potential Role of microRNA-183 as a Tumor Suppressor in Hepatocellular Carcinoma

Cellular Physiology and Biochemistry ◽

10.1159/000495825 ◽

2018 ◽

Vol 51 (5) ◽

pp. 2065-2072 ◽

Cited By ~ 3

Author(s):

Wei Bian ◽

Hongfei Zhang ◽

Miao Tang ◽

Shaojun Zhang ◽

Lichao Wang ◽

...

Keyword(s):

Hepatocellular Carcinoma ◽

Hepg2 Cells ◽

Molecular Mechanisms ◽

The Cancer Genome Atlas ◽

Migration And Invasion ◽

Metastatic Progression ◽

Mesenchymal Transition ◽

Reporter Assays

Background/Aims: Disseminated tumors, known as metastases, are responsible for ninety-percent of mortality due to cancer. Epithelial to mesenchymal transition, a phenomenon required for morphological conversion of non-motile discoid shaped epithelial cells to highly motile spindle-shaped mesenchymal cells, is thought to be a pre-requisite for metastatic progression. Metastasis-associated 1 (MTA1) protein is a prime inducer of EMT and metastatic progression in all solid tumors including hepatocellular carcinoma (HCC). However, the molecular mechanisms that regulate the expression and function of MTA1 in HCC have not been elucidated. Methods: In silico prediction algorithms were used to find microRNAs (miRNAs) that may target MTA1. We examined the relationship between the expression of MTA1 and miR-183 using quantitative real time PCR. We also determined the levels of the MTA1 protein using immunohistochemistry. Reporter assays, in the presence and absence of the miR-183 mimic, were used to confirm MTA1 as a bona fide target of miR183. The effect of miR-183 on HCC pathogenesis was determined using a combination of in vitro migration and invasion assay, together with in vivo xenograft experiments. The correlation between miR-183 and MTA1 expression was also studied in samples from HCC patients, and in The Cancer Genome Atlas dataset. Results: Analysis of the sequence database revealed that MTA1 is a putative target of miR-183. MTA1 protein and RNA expression showed opposite trends to miR-183 expression in breast, renal, prostate, and testicular tissue samples from cancer patients, and in the metastatic HCC cell line HepG2. An inverse correlation was also observed between MTA1 (high) and miR-183 (low) expression within samples from HHC patients and in the TCGA dataset. Reporter assays in HepG2 cells showed that miR-183 could inhibit translation of a reporter harboring the wild-type, but not the mutant miR-183 3’-untranslated region (UTR). In addition, miR-183 significantly inhibited in vitro migration and invasion in HepG2 cells, and in vivo hepatic metastasis. Conclusion: Our results reveal a novel post-transcriptional regulatory mechanism for MTA1 expression via miR-183, which is suppressed during HCC pathogenesis.

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Upregulation of SGOL2 Predicts Poor Prognosis and Facilitates Hepatocellular Carcinoma Progression via Dysregulating the Cell Cycle by Directly Activating MAD2

10.21203/rs.3.rs-560609/v1 ◽

2021 ◽

Author(s):

Qingqing Hu ◽

Xiaochu Hu ◽

Yalei Zhao ◽

Lingjian Zhang ◽

Ya Yang ◽

...

Keyword(s):

Hepatocellular Carcinoma ◽

Cell Cycle ◽

The Cancer Genome Atlas ◽

Loss Of Function ◽

Protein Levels ◽

Cancer Genome Atlas ◽

Centromeric Protein ◽

Hcc Cells

Abstract Background: Hepatocellular carcinoma (HCC) is the third leading cause of cancer-related death worldwide. Shugoshin-like protein 2 (SGOL2) is a centromeric protein that ensures the correct and orderly process of mitosis by protecting and maintaining centripetal adhesions during meiosis and mitosis. However, the role of SGOL2 in cancer is not well understood. Methods: The mRNA and protein levels of SGOL2 and survival analysis were conducted in The Cancer Genome Atlas (TCGA) and further validated in 2 independent cohorts. Differential genes correlated with SGOL2 and mitotic arrest deficient 2 like 1 (MAD2) were obtained using LinkedOmics. Subsequently, loss-of-function and rescue assays were carried out in vitro and in vivo to assess the functions of SGOL2 in hepatic tumorigenisis. Findings: We found that SGOL2 was significantly overexpressed in HCC and predicted unfavorable overall survival in HCC patients. Next, we identified 47 differentially expressed genes positively correlated with both SGOL2 and MAD2 to be mainly involved in the cell cycle. In addition, SGOL2 downregulation suppressed the migration, invasion, proliferation, stemness and EMT of HCC cells and inhibited tumorigenesis in vivo. Furthermore, SGOL2 promoted tumor proliferation by activating MAD2-induced cell cycle dysregulation, which could be reversed by the MAD2 inhibitor M2I-1. We also proved that SGOL2 activated MAD2 by directly binding with MAD2. Conclusions: The results of this study showed that SGOL2 acts as an oncogene in HCC cells by directly activating MAD2 and then dysregulating the cell cycle, thereby providing a potential target for HCC patients in the future.

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LncRNA DCST1-AS1 functions as a competing endogenous RNA to regulate FAIM2 expression by sponging miR-1254 in hepatocellular carcinoma

Clinical Science ◽

10.1042/cs20180814 ◽

2019 ◽

Vol 133 (2) ◽

pp. 367-379 ◽

Cited By ~ 7

Author(s):

Jing Chen ◽

Di Wu ◽

Yue Zhang ◽

Yong Yang ◽

Yunfei Duan ◽

...

Keyword(s):

Hepatocellular Carcinoma ◽

Clinical Significance ◽

Biological Function ◽

The Cancer Genome Atlas ◽

Cycle Arrest ◽

Cancer Genome Atlas ◽

Apoptosis Inhibitor ◽

Hcc Cells

Abstract Long non-coding RNAs (lncRNAs) play important roles in a variety of tumours; however, their biological function and clinical significance in hepatocellular carcinoma (HCC) are still unclear. In the present study, the clinical significance, biological function and regulatory mechanisms of lncRNA DCST1-AS1 in HCC were investigated. Differential lncRNAs in HCC were identified based on The Cancer Genome Atlas (TCGA) database. The biological function and mechanism of DCST1-AS1 were studied in vitro and in vivo. LncRNA DCST1-AS1 was highly expressed in HCC tissues, and the high expression of DCST1-AS1 was significantly correlated with larger tumours and shorter survival time. Moreover, DCST1-AS1 knockout significantly inhibited proliferation, promoted apoptosis and cycle arrest of HCC cells, and inhibited tumour growth in vivo. According to functional analysis, DCST1-AS1 competitively bound miR-1254, thus blocking the silencing effect of miR-1254 on the target gene Fas apoptosis inhibitor 2 (FAIM2). A novel lncRNA DCST1-AS1 that functions as an oncogene in HCC was discovered. DCST1-AS1 up-regulates the expression of FAIM2 by up-regulating the expression of miR-1254, ultimately promoting the proliferation of HCC cells. This research provides new therapeutic targets for HCC.

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Primary Cilia Blockage Promotes the Malignant Behaviors of Hepatocellular Carcinoma via Induction of Autophagy

BioMed Research International ◽

10.1155/2019/5202750 ◽

2019 ◽

Vol 2019 ◽

pp. 1-14

Author(s):

Lian Liu ◽

Jia-Qi Sheng ◽

Mu-Ru Wang ◽

Yun Gan ◽

Xiao-Li Wu ◽

...

Keyword(s):

Hepatocellular Carcinoma ◽

Primary Cilia ◽

The Cancer Genome Atlas ◽

Migration And Invasion ◽

Serum Starvation ◽

Autophagic Flux ◽

And Function ◽

Hcc Cells

Primary cilia are organelles protruding from cell surface into environment that function in regulating cell cycle and modulating cilia-related signal. Primary ciliogenesis and autophagy play important roles in tumorigenesis. However, the functions and interactions between primary cilia and autophagy in hepatocellular carcinoma (HCC) have not been reported yet. Here, we aimed to investigate the relationship and function of primary cilia and autophagy in HCC. In vitro, we showed that serum starvation stimuli could trigger primary ciliogenesis in HCC cells. Blockage of primary ciliogenesis by IFT88 silencing enhanced the proliferation, migration, and invasion ability of HCC cells. In addition, inhibition of primary cilia could positively regulate autophagy. However, the proliferation, migration, and invasion ability which were promoted by IFT88 silencing could be partly reversed by inhibition of autophagy. In vivo, interference of primary cilia led to acceleration of tumor growth and increase of autophagic flux in xenograft HCC mouse models. Moreover, IFT88 high expression or ATG7 low expression in HCC tissues was correlated with longer survival time indicated by the Cancer Genome Atlas (TCGA) analysis. In conclusion, our study demonstrated that blockage of primary ciliogenesis by IFT88 silencing had protumor effects through induction of autophagy in HCC. These findings define a newly recognized role of primary cilia and autophagy in HCC.

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A Preliminary Investigation of PVT1 on the Effect and Mechanisms of Hepatocellular Carcinoma: Evidence from Clinical Data, a Meta-Analysis of 840 Cases, and In Vivo Validation

Cellular Physiology and Biochemistry ◽

10.1159/000491534 ◽

2018 ◽

Vol 47 (6) ◽

pp. 2216-2232 ◽

Cited By ~ 9

Author(s):

Yu Zhang ◽

Dong-yue Wen ◽

Rui Zhang ◽

Jia-cheng Huang ◽

Peng Lin ◽

...

Keyword(s):

Hepatocellular Carcinoma ◽

Cell Proliferation ◽

Meta Analysis ◽

Target Prediction ◽

The Cancer Genome Atlas ◽

Gene Microarray ◽

Prediction Algorithms ◽

Correlation Trend

Background/Aims: Hepatocellular carcinoma (HCC) remains a difficult problem that significantly affects the survival of the afflicted patients. Accumulating evidence has demonstrated the functions of long non-coding RNA (lncRNA) in HCC. In the present study, we aimed to explore the potential roles of PVT1 in the tumorigenesis and progression of HCC. Methods: In this study, quantitative reverse transcription-polymerase chain reaction (RT-qPCR) was applied to detect the differences between PVT1 expression in HCC tissues and cell lines. Then, the Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases were searched to confirm the relationship between PVT1 expression and HCC. Moreover, a meta-analysis comprising TCGA, GEO, and RT-qPCR was applied to estimate the expression of PVT1 in HCC. Then, cell proliferation was evaluated in vitro. A chicken chorioallantoic membrane (CAM) model of HCC was constructed to measure the effect on tumorigenicity in vivo. To further explore the sponge microRNA (miRNA) of PVT1 in HCC, we used TCGA, GEO, a gene microarray, and target prediction algorithms. TCGA and GEO and the gene microarray were used to select the differentially expressed miRNAs, and the different target prediction algorithms were applied to predict the target miRNAs of PVT1. Results: We found that PVT1 was markedly overexpressed in HCC tissue than in normal liver tissues based on both RT-qPCR and data from TCGA, and the overexpression of PVT1 was closely related to the gender and race of the patient as well as to higher HCC tumor grades. Also, a meta-analysis of 840 cases from multiple sources (TCGA, GEO and the results of our in-house RT-qPCR) showed that PVT1 gained moderate value in discriminating HCC patients from normal controls, confirming the results of RT-qPCR. Additionally, the upregulation of PVT1 could promote HCC cell proliferation in vitro and vivo. Based on the competing endogenous RNA (ceRNA) theory, the PVT1/miR-424-5p/INCENP axis was finally selected for further research. The in silico prediction revealed that there were complementary sequences between PVT1 and miR-424-5p as well as between miR-424-5p and INCENP. Furthermore, a negative correlation trend was found between miR-424-5p and PVT1 based on RT-qPCR, whereas a positive correlation trend was found between PVT1 and INCENP based on data from TCGA. Also, INCENP small interfering RNA (siRNA) could significantly inhibit cell proliferation and viability. Conclusions: We hypothesized that PVT1 could affect the biological function of HCC cells via targeting miR-424-5p and regulating INCENP. Focusing on the new insight of the PVT1/miR-424-5p/INCENP axis, this study provides a novel perspective for HCC therapeutic strategies.

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Dickkopf-1 contributes to hepatocellular carcinoma tumorigenesis by activating the Wnt/β-catenin signaling pathway

Signal Transduction and Targeted Therapy ◽

10.1038/s41392-019-0082-5 ◽

2019 ◽

Vol 4 (1) ◽

Cited By ~ 2

Author(s):

Rui Zhang ◽

Hao-Ming Lin ◽

Ruth Broering ◽

Xiang-de Shi ◽

Xian-huan Yu ◽

...

Keyword(s):

Hepatocellular Carcinoma ◽

Signaling Pathway ◽

Tumor Formation ◽

In Vivo Studies ◽

Qrt Pcr ◽

Subsequent Investigation ◽

Dkk1 Expression ◽

Tumor Number

AbstractDysregulation of dickkopf-related protein 1 (DKK1) expression has been reported in a variety of human cancers. We previously reported that DKK1 was upregulated in hepatocellular carcinoma (HCC). However, the role of DKK1 in HCC remains unclear. This study aimed to investigate the clinical significance and biological functions of DKK1 in HCC. The expression of DKK1 was examined in cirrhotic and HCC tissues by immunohistochemistry and quantitative real-time polymerase chain reaction (qRT-PCR). DKK1 was silenced or overexpressed in HCC cell lines, and in vitro and in vivo studies were performed. Immunohistochemistry revealed that DKK1 was weakly expressed in cirrhotic tissues (8/22, 36.4%) but upregulated in HCC tissues (48/53, 90.6%, cohort 1). Significant upregulation of DKK1 was observed in 57.6% (19/33, cohort 2) of HCC tissues by qRT-PCR, and the expression of DKK1 was associated with tumor size (P = 0.024) and tumor number (P = 0.019). Genetic depletion of DKK1 impaired the proliferation, colony-forming ability, invasion, and tumor formation of HCC cells (HepG2 and HUH-7). Conversely, forced expression of DKK1 increased the proliferation, colony-forming ability, and invasion of HepG2 and HUH-7 cells in vitro and enhanced tumor formation in vivo. Subsequent investigation revealed that the DKK1-mediated proliferation and tumorigenicity of HepG2 and HUH-7 cells is dependent on the Wnt/β-catenin signaling pathway. These findings indicate that DKK1 plays an oncogenic role in HCC by activating the Wnt/β-catenin signaling pathway.

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GLP-1 Analogue Liraglutide Enhances SP-A Expression in LPS-Induced Acute Lung Injury through the TTF-1 Signaling Pathway

Mediators of Inflammation ◽

10.1155/2018/3601454 ◽

2018 ◽

Vol 2018 ◽

pp. 1-14 ◽

Cited By ~ 16

Author(s):

Tao Zhu ◽

Changyi Li ◽

Xue Zhang ◽

Chunyan Ye ◽

Shuo Tang ◽

...

Keyword(s):

Acute Lung Injury ◽

Lung Injury ◽

Signaling Pathway ◽

Pulmonary Inflammation ◽

Protein A ◽

Insulin Level ◽

Underlying Mechanism ◽

Ultrastructural Changes

The reduction of pulmonary surfactant (PS) is essential for decreased pulmonary compliance and edema in acute lung injury (ALI). Thyroid transcription factor-1 (TTF-1) plays a major role in the regulation of surfactant protein-A (SP-A), the most abundant protein component of PS. Simultaneously, the glucagon-like peptide-1 (GLP-1) analogue can enhance SP-A expression in the lung. However, the underlying mechanism is still unknown. The purpose of this study was to explore whether liraglutide, a GLP-1 analogue, upregulates SP-A expression through the TTF-1 signaling pathway in ALI. In vivo, a murine model of ALI was induced by lipopolysaccharide (LPS). Pulmonary inflammation, edema, insulin level, ultrastructural changes in type II alveolar epithelial (ATII) cells, and SP-A and TTF-1 expression were analyzed. In vitro, rat ATII cells were obtained. SP-A and TTF-1 expression in cells was measured. ShRNA-TTF-1 transfection was performed to knock down TTF-1 expression. Our data showed that LPS-induced lung injury and increase in insulin level, and LPS-induced reduction of SP-A and TTF-1 expression in both the lung and cells, were significantly compromised by liraglutide. Furthermore, we also found that these effects of liraglutide were markedly blunted by shRNA-TTF-1. Taken together, our findings suggest that liraglutide enhances SP-A expression in ATII cells and attenuates pulmonary inflammation in LPS-induced ALI, most likely through the TTF-1 signaling pathway.

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LINC00467 Promotes Tumor Progression via Regulation of the NF-kb Signal Axis in Bladder Cancer

Frontiers in Oncology ◽

10.3389/fonc.2021.652206 ◽

2021 ◽

Vol 11 ◽

Author(s):

Jiawei Xiao ◽

Lian Gong ◽

Mengqing Xiao ◽

Dong He ◽

Liang Xiang ◽

...

Keyword(s):

Bladder Cancer ◽

Signaling Pathway ◽

Molecular Mechanisms ◽

Animal Experiments ◽

Bioinformatic Analysis ◽

New Strategy ◽

Patient Prognosis

PurposeLong non-coding RNAs (lncRNAs) play an important role in the occurrence and development of bladder cancer, but the underlying molecular mechanisms remain largely unknown. In this study, we found that LINC00467 was significantly highly expressed in bladder cancer through bioinformatic analysis. The present study aimed to explore the role of LINC00467 in bladder cancer and its possible underlying molecular mechanisms.MethodsThe expression of LINC00467 was obtained from GEO (GSE31189), the TCGA database, and qRT-PCR. The role of LINC00467 in bladder cancer was assessed both in vitro and in vivo. RIP, RNA pulldown, and CO-IP were used to demonstrate the potential mechanism by which LINC00467 regulates the progression of bladder cancer.ResultsThrough the analysis of GEO (GSE133624) and the TCGA database, it was found that LINC00467 was highly expressed in bladder cancer tissues and that the expression of LINC00467 was significantly negatively correlated with patient prognosis. Cell and animal experiments suggest that LINC00467 promotes the proliferation and invasion of bladder cancer cells. On the one hand, LINC00467 can directly bind to NF-kb-p65 mRNA to stabilize its expression. On the other hand, LINC00467 can directly bind to NF-kb-p65 to promote its translocation into the nucleus to activate the NF-κB signaling pathway, which promotes the progression of bladder cancer.ConclusionsLINC00467 is highly expressed in bladder cancer and can promote the progression of bladder cancer by regulating the NF-κB signaling pathway. Therefore, targeting LINC00467 is very likely to provide a new strategy for the treatment of bladder cancer and for improving patient prognosis.

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Telocytes Promote the Metastasis of Hepatocellular Carcinoma by Activating ERK Signaling Pathway and Sponging miR-942-3p to Impact MMP9

10.21203/rs.3.rs-364558/v1 ◽

2021 ◽

Author(s):

Ying Xu ◽

Hu Tian ◽

Chao Guang Luan ◽

Kai Sun ◽

peng Jin Bao ◽

...

Keyword(s):

Hepatocellular Carcinoma ◽

Liver Cancer ◽

Signaling Pathway ◽

Erk Signaling ◽

Cancer Tissue ◽

Proliferative Potential ◽

Cancer Tissues ◽

Hcc Cells

Abstract Background: Hepatocellular carcinoma(HCC) in China is considered as a familiar malignant tumor with poor prognosis, high metastasis and disease relapse. Telocytes(TCs) have been verified to participate in progresses of tumorigenesis, invasions and migrations by secreting functional proteins and transmitting cell-to-cell information. Extracellular signal-regulared protein kinase(ERK) signal pathway is a vital mechanism driving cell proliferation, metastasis and apoptosis, but whether this molecular signaling mechanism contributes to matrix metalloproteinase-9(MMP) expression of TCs remains unclear. Methods: Telocytes and MMP9 expression in the liver cancer tissues are measured by immunohistochemistry assay, Westen blot assay and RT-PCR technique, meanwhile primary telocytes from liver para-cancer tissues are cultured in vitro. To demonstrate the function of telocytes for hepatocellular carcinoma, the metastatic cancer animal model is established by three typs of liver cancer cell-lines in vivo. Results: In our study, we elucidate that TCs in the para-cancer tissue can promote the metastasis of HCC cells by MMP-9 expression, in vitro and in vivo. PDGF derived from HCC cells has a capacity to activate Ras/ERK signaling pathway of TC as a result of accelerating MMP-9 expression, but it’s no significant for proliferative potential and apoptotic rate of TCs. While tyrosine kinase inhibitors and miR-942-3p suppress MMP-9 expression to make loss functions of TCs. Various mutations of TCs are also tested and single nucleotide polymorphisms of MMP-9 may be the potentially molecular mechanism of increasing protein expression in the invasive process of HCC. Conclusion: Our results demonstrate two potential mechanisms between HCC cells and TCs, suggesting that TC is a novel marker and target on deciphering reasons of cancer metastasis.

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