Multi-omics integrated analyzed the origin of intrahepatic mucinous cholangiocarcinoma: a case report.

Intrahepatic mucinous cholangiocarcinoma (IMCC) is a rare subtype of intrahepatic cholangiocarcinoma (IHCC). Limited data describe the genetic characteristics of IMCC and insights on its pathogenesis are lacking. Here, we employed a multi-omics approach to analyze somatic mutations, transcriptome, proteome and metabolome of tumor tissue obtained from a case of IMCC in order to clarify the pathogenesis of IMCC. A total of 54 somatic mutations were detected, including a G12D mutation in KRAS that is likely to be involved in the onset of IMCC. The genes consistently up-regulated at the transcription level and in the proteome were enriched for mucin and mucopolysaccharide biosynthesis, for cell cycle functions and for inflammatory signaling pathways. The consistently down-regulated genes were enriched in bile synthesis and fatty acid metabolism pathways. Further multi-omics analysis found that mucin synthesis by MUC4 and MUC16 was elevated by up-regulated expression of mesothelin (MSLN). Moreover, transcription factor ONECUT3 was identified that possibly activates the transcription of mucin and mucopolysaccharide biosynthesis in IMCC.

SHARPIN promotes cell proliferation of cholangiocarcinoma and inhibits ferroptosis via p53/SLC7A11/GPX4 signaling.

SHARPIN is a tumor-associated gene involved in the growth and proliferation of many tumor types. A function of SHARPIN in cholangiocarcinoma (CCA) is so far unclear. Here, we studied the role and function of SHARPIN in CCA and revealed its relevant molecular mechanism. The expression of SHARPIN was analyzed in cholangiocarcinoma tissues from patients using immunohistochemistry, quantitative PCR, and western blot analysis. Expression of SHARPIN was suppressed/overexpressed by siRNA silencing or lentiviral overexpression vector, and the effect on cell proliferation was determined by the CCK-8 assay and flow cytometry. Accumulation of reactive oxygen species was measured with MitoTracker, and JC-1 staining showed mitochondrial fission/fusion and mitochondrial membrane potential changes as a result of the silencing or overexpression. The ferroptosis marker solute carrier family 7 member 11 (SLC7A11), glutathione peroxidase 4 (GPX4), and the antioxidant enzymes superoxide dismutase 1 (SOD-1) and SOD-2 were analyzed by western blot. The results showed that SHARPIN expression was increased in CCA tissue, and this was involved in cell proliferation. SHARPIN silencing resulted in accumulated reactive oxygen species, reduced mitochondrial fission, and a reduced mitochondrial membrane potential. Silencing of SHARPIN inhibited the ubiquitination and degradation of p53, and downregulated levels of SLC7A11, GPX4, SOD-1, and SOD-2, all of which contributed to excessive oxidative stress that leads to ferroptosis. Overexpression of SHARPIN would reverse the above process. The collected data suggest that in CCA, SHARPIN-mediated cell ferroptosis via the p53/SLC7A11/GPX4 signaling pathway is inhibited. Targeting SHARPIN might be a promising approach for the treatment of CCA.

TGF-ß1 induced deficiency of linc00261 promotes epithelial-mesenchymal-transition and stemness of hepatocellular carcinoma via modulating SMAD3.

Emerging evidence suggests that long non-coding RNAs (lncRNAs) play important roles in the metastasis and recurrence of hepatocellular carcinoma (HCC). A kinds of lncRNAs were found to be involved in regulating epithelial-mesenchymal transition (EMT) or stem-like traits in human cancers, however, the molecular mechanism and signaling pathways targeting EMT and stemness remains largely unknown. Previously, we found that linc00261 was down-regulated in HCC and associated with multiple worse clinical pathological parameters and poor prognosis. Here, we show that linc00261 was down-regulated in TGF-ß1 stimulated cells, and forced expression of linc00261 attenuated EMT and stem-like traits in HCC. Linc00261 also inhibited the tumor sphere forming in vitro and decreased the tumorigenicity in vivo. Furthermore, we revealed that linc00261 suppressed the expression and phosphorylation of SMAD3 (p-SMAD3), which could be core transcriptional modulator in TGF-ß1 signaling mediated EMT and the acquisition of stemness traits. A negative correlation between linc00261 and p-SMAD3 was determined in HCC samples. Conclusion: Our study revealed that linc00261 suppressed EMT and stem-like traits in HCC cells by inhibiting TGF-ß1/SMAD3 signaling.

Epigenetically silenced linc00261 contributes to the metastasis of hepatocellular carcinoma via inducing the deficiency of FOXA2 transcription.

Hepatocellular carcinoma (HCC) is one of the most common malignancies worldwide. In recent decades, long non-coding RNAs (lncRNAs) have attracted increasing attention and have been reported to play important roles in human cancers, making them ideal candidates for precise disease assessment and treatment. Our previous study found that the loss of linc00261 was significantly correlated with the malignant biological behaviors of HCC, particularly MVI, and serves as an excellent independent prognostic factor for recurrence-free survival. In this study, our in-depth research demonstrated that linc00261 inhibits epithelial-mesenchymal transition (EMT) in liver cancer cells, thereby suppressing migration, invasion, and the formation of lung metastatic lesions. Moreover, linc00261 and its neighbor gene FOXA2 were positively correlated in HCC, the gain- and loss-of-function analyses indicated that linc00261 transcriptionally promotes the expression of FOXA2. Additionally, bioinformatic analysis and rescue assays confirmed that linc00261 partially suppresses migration, invasion, and EMT by upregulating FOXA2 expression. Molecular mechanism studies showed that linc00261 transcriptionally upregulates FOXA2 in cis by recruiting SMAD3. Finally, we identified EZH2 is responsible for linc00261 transcription repression via modulating trimethylation of H3K27 at Lys27 (H3K27Me3), both EZH2 and H3K27Me3 were negatively correlated with linc00261 expression in HCC. In conclusion, these findings demonstrated a crucial role of linc00261 in HCC metastasis, and that EZH2/linc00261/FOXA2 axis might reveal potential prognostic factors and be applied as therapeutic targets for HCC metastasis.

Pseudogene Annexin A2 Pseudogene 1 Contributes to Hepatocellular Carcinoma Progression by Modulating Its Parental Gene ANXA2 via miRNA-376a-3p.

BACKGROUND: Pseudogenes are defined as key regulators in cancer initiation and progression. But their biological function and clinical significance in hepatocellular carcinoma (HCC) remain to be elucidated. In the current study, we identified a novel pseudogene, Annexin A2 pseudogene 1 (ANXA2P1), in HCC and explored its underlining molecular mechanism. METHODS AND RESULTS: We analyzed the expression pattern of ANXA2P1 in a TCGA dataset and an HCC sample cohort and evaluated its clinical significance. The biological effects on HCC cells proliferation, migration, invasion and epithelial-mesenchymal transition (EMT) process were assessed by Cell Counting Kit-8 assay, Transwell assay and Western blot, respectively. The ANXA2P1/miR-376a-3p/ANXA2 axis was determined by bioinformatics analysis and dual-luciferase reporter assays. ANXA2P1 exerted as an oncogene that was significantly overexpressed in HCC tissues and was associated with disease progression and unfavorable prognosis of HCC patients. ANXA2P1 knockdown suppressed cell growth, cell migration and invasion and reversed EMT phenotype in HCC. Mechanistically, ANXA2P1 acts as a competing endogenous RNA for miR-376a-3p, thereby leading to the upregulation of its cognate gene ANXA2. CONCLUSIONS: ANXA2P1/miR-376a-3p/ANXA2 axis plays an important role in the progression of HCC. Our findings may provide valuable therapeutic target for treating HCC.

Deficiency of pseudogene UPAT leads to hepatocellular carcinoma progression and forms a positive feedback loop with ZEB1.

Hepatocellular carcinoma (HCC) is a common disease worldwide. Accumulating reports have evidenced the internal connection between epithelial-mesenchymal transition (EMT) and cancer stem cells (CSCs), as well as their significance in metastasis and post-operative recurrence. In this study, we investigated an interesting ubiquitin-proteasome pathway associated pseudogene of AOC4, also known as UPAT, and showed that it was downregulated in 39.78% (37/93) of patients with hepatitis B virus (HBV)-related HCC. Downregulation of UPAT was associated with multiple worse clinicopathological parameters, as well as decreased recurrence-free survival (RFS). In vitro and in vivo assays found that overexpression of UPAT significantly suppressed cellular migration, invasion, EMT processes, and CSC properties. Mechanistic studies showed that UPAT promoted ZEB1 degradation via a ubiquitin-proteasome pathway and, in contrast, ZEB1 transcriptionally suppressed UPAT by binding to multiple E-box (CACCTG) elements in the promoter region. Moreover, UPAT was negatively correlated with ZEB1 protein in HCC tissues, their combined expression discriminated RFS outcomes for patients with HBV-related HCC. These data on the UPAT-ZEB1 circuit-mediated pathway will further knowledge on EMT and CSCs, and may help to develop novel therapeutic approaches for the prevention of HCC metastasis.

MALAT1 functions as a competing endogenous RNA to regulate SMAD5 expression by acting as a sponge for miR-142-3p in hepatocellular carcinoma.

BACKGROUND: Long non-coding RNAs are involved in the pathology of various tumors, including hepatocellular carcinoma. The expression of metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) is increased in numerous types of tumors and is involved in tumor cell proliferation, migration, invasion and apoptosis. MALAT1 level was reported to be upregulated in hepatocellular carcinoma tissues, but its roles and the specific molecular mechanisms are still unclear. METHODS: The expression of MALAT1 and miR-142-3p in hepatocellular carcinoma tissues, cell lines and adjacent non-tumor tissues was assessed by Q-PCR. The putative-binding sites between MALAT1 and miR-142-3p were predicted by bioinformatics analysis. The expression of MALAT1 in HepG2 and SMMC-7721 cells was knocked down by transfection with MALAT1 siRNAs. Cell viability was assessed by the Cell Counting Kit-8 (CCK-8) assay after the indicated transfection in HepG2 and SMMC-7721 cells. Cell proliferation was assessed by EdU assay, and cell apoptosis was explored by flow cytometry. The migration and invasion potency of HepG2 and SMMC-7721 cells was assessed by the cell migration assay and matrigel invasion assay. Protein level of vimentin, E-cadherin and SMAD5 were assessed by Western blot. RESULTS: Overexpressed MALAT1 acts as a competing endogenous RNA sponge for miR-142-3p in hepatocellular carcinoma. The knockdown of MALAT1 inhibited the proliferation, migration, invasion, and epithelial cell-to-mesenchymal transition (EMT), and promoted apoptosis of hepatocellular carcinoma cells via miR-142-3p. MiR-142-3p inhibited cell proliferation, migration, invasion and EMT, and promoted the cell apoptosis by targeting SMAD5 in hepatocellular carcinoma. MALAT1 promoted tumor growth by regulating the expression of miR-142-3p in vivo. CONCLUSION: MALAT1 promoted cell proliferation, migration, and invasion of hepatocellular carcinoma cells by antagonizing miR-142-3p.

Frizzled 2-induced epithelial-mesenchymal transition correlates with vasculogenic mimicry, stemness, and Hippo signaling in hepatocellular carcinoma.

Prior observation has indicated that Frizzled 2 (FZD2)-induced epithelial-mesenchymal transition (EMT) could be a key step in metastasis and early recurrence of hepatocellular carcinoma (HCC). However, the mechanism underlying tumor development and progression due to aberrant FZD2 expression is poorly defined. Here, we provide evidence that FZD2 is a driver for EMT, cancer stem cell properties, and vasculogenic mimicry (VM) in HCC. We found that FZD2 was highly expressed in two cohorts of Chinese hepatitis B virus-related HCC patients, and that high FZD2 expression was associated with poor prognosis. Concerning the mechanism, gain- and loss-of-function experiments showed the oncogenic action of FZD2 in HCC cell proliferation, apoptosis, migration, and invasion. Further investigations in vitro and in vivo suggested that FZD2 promotes the EMT process, enhances stem-like properties, and confers VM capacity to HCC cells. Notably, integrative RNA sequencing analysis of FZD2-knockdown cells indicated the enrichment of Hippo signaling pathway. Taken together, our data suggest for the first time that FZD2 could promote clinically relevant EMT, CD44+ stem-like properties, and the VM phenotype in HCC involving a potential Hippo signaling pathway-dependent mechanism, and should be considered as a promising therapeutic target for the treatment of HCC.

Circulating Tumor Cell Phenotype Indicates Poor Survival and Recurrence After Surgery for Hepatocellular Carcinoma.

BACKGROUND: Circulating tumors cells (CTCs) may be a promising prognostic marker for patients with malignant tumors. However, there are few reports regarding its value for hepatocellular carcinoma (HCC) patients. AIMS: To investigate CTCs with epithelial and mesenchymal phenotypes as a potential prognostic biomarker for HCC patients. METHODS: Peripheral blood samples were obtained from 165 HCC patients before radical surgery. CTCs were isolated via the CanPatrol CTC enrichment technique and classified using epithelial-mesenchymal transition (EMT) markers. The relationship of CTC phenotype with clinicopathological factors and HCC recurrence in patients was analyzed. RESULTS: CTC-positive status (count ≥ 2/5 mL) was found in 70.9% of the 165 HCC patients. Increased CTC number was more common in patients with higher AFP levels, multiple tumors, advanced TNM and BCLC staging, and presence of embolus or microembolus (P < 0.05). CTCs heterogeneity was noted using EMT markers. Mesenchymal CTCs were significantly correlated with high AFP levels, multiple tumors, advanced TNM and BCLC stage, presence of embolus or microembolus, and earlier recurrence (P < 0.05). The presence of mesenchymal CTCs predicted the shortest relapse-free survival, followed by mixed phenotypic CTCs, and then epithelial CTCs (P < 0.001). CONCLUSION: CTC phenotype may serve as a prognostic indicator for HCC patients. CTCs assessment should include phenotypic identification tailored to characterize cells based on epithelial and mesenchymal markers.

[Expression of Wnt5b in patients with HBV-related hepatocellular carcinoma and its clinical significance].

OBJECTIVE: To investigate the expression of Wnt5b in hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC) tissues and its correlation with the clinicopathological parameters. METHODS: Quantitative real-time polymerase chain reaction (qRT-PCR) and immunohistochemical staining were employed to measure Wnt5b mRNA and protein expressions in two groups of HBV-related HCC patients (100 cases in each) selected from a cohort of 289 cases with HBV-related HCC using simple random sampling method. The correlation of Wnt5b expression with the clinicopathological parameters and the prognosis of HCC patients was analyzed. RESULTS: Wnt5b mRNA expression was significantly higher in HCC tissues than that of adjacent noncancerous tissues in 65.0% (65/100) of the cases, and the positivity rate of Wnt5b protein was significantly higher in HCC tissues than that of adjacent noncancerous tissues (58.0% vs 22.0%, P<0.05). Wnt5b expression was significantly correlated with the tumor size (P<0.05), tumor number (P<0.01, only at the protein level), tumor differentiation (P<0.01, only at the protein level), TNM stage (P<0.05), BCLC stage (P<0.05), metastasis (P<0.05) and recurrence (P<0.01). The patients with up-regulated Wnt5b mRNA and protein had a shorter relapse-free survival (P<0.01). CONCLUSION: s Up-regulated Wnt5b might contribute to the progression of HBV-related HCC and predicts a poor prognosis.

Loss of tumor suppressor miR-126 contributes to the development of hepatitis B virus-related hepatocellular carcinoma metastasis through the upregulation of ADAM9.

Hepatocellular carcinoma is the most common histological type of primary liver cancer, which represents the second leading cause of cancer-related mortality. MiR-126 was reported to be downregulated in hepatocellular carcinoma tissues, compared with its levels in noncancerous tissues. However, baseline miR-126 expression levels in hepatitis B virus-related hepatocellular carcinoma patients who did not undergo pre-operational treatment remains unknown since hepatitis B virus infection and pre-operational transcatheter arterial chemoembolization were shown to upregulate miR-126 expression. Here, we demonstrated that miR-126 is generally downregulated in a homogeneous population of pre-operational treatment-naïve hepatitis B virus-related hepatocellular carcinoma patients (84.0%, 84/100), and its expression is significantly associated with pre-operational alpha-fetoprotein levels ( p < 0.05), microvascular invasion ( p < 0.05), tumor metastasis ( p < 0.05), as well as early recurrence (12 months after surgery; p < 0.01). Furthermore, the results of our study revealed that miR-126 is negatively correlated with ADAM9 expression in hepatitis B virus-related hepatocellular carcinoma patients. Overexpression of miR-126 was shown to attenuate ADAM9 expression in hepatocellular carcinoma cells, which subsequently inhibits cell migration and invasion in vitro. In addition, Cox proportional hazards regression model analysis showed that ADAM9 levels, tumor number, microvascular invasion, and tumor metastasis rate represent independent prognostic factors for shorter recurrence-free survival. In conclusion, we demonstrated that the loss of tumor suppressor miR-126 in hepatitis B virus-related hepatocellular carcinoma cells contributes to the development of metastases through the upregulated expression of its target gene, ADAM9. MiR-126-ADAM9 pathway-based therapeutic targeting may represent a novel approach for the inhibition of hepatitis B virus-related hepatocellular carcinoma metastases.

NVM-1 predicts prognosis and contributes to growth and metastasis in hepatocellular carcinoma.

Novel metastasis-promoting gene 1 (NVM-1) has a significantly elevated protein level in a variety of tumor tissues and is involved in metastasis. However, its functions in hepatocellular carcinoma (HCC) are not clear. The current study aimed to investigate the functions of NVM-1 in cell proliferation, apoptosis, and epithelial-mesenchymal transition in HCC. NVM-1 protein expression in HCC was assessed by immunohistochemical staining. In vitro, cell proliferation, apoptosis, and aggressiveness were determined by CCK-8, fluorescence-assisted cell sorting, TdT-UTP nick-end labeling, and transwell assays, respectively. For in vivo studies, NVM-1 knockdown HCC cells were transplanted into BALB/c nude mice. NVM-1 was frequently upregulated in HCC tissues and positive NVM-1 expression was linked with poor prognosis. NVM-1 depletion significantly inhibited cell proliferation, migration, and invasion abilities in vitro and in vivo. Apoptosis was induced after NVM-1 knockdown. In conclusion, positive NVM-1 expression confers poor prognosis to HCC patients and the NVM-1 protein level correlates with HCC cell proliferation, apoptosis, and EMT.

Elevated UHRF1 expression contributes to poor prognosis by promoting cell proliferation and metastasis in hepatocellular carcinoma.

Ubiquitin-like with plant homeodomain and ring finger domains, 1 (UHRF1) is overexpressed in a variety of tumor tissues and is negatively correlated with prognosis of patients with cancers, yet so far, a comprehensive study of UHRF1 in hepatocellular carcinoma (HCC) has not been conducted. The present study was designed to explore the expression of UHRF1, associated clinical implications, and its possible functions in HCC. Reverse transcription-polymerase chain reaction and immunohistochemical staining were used to detect UHRF1 expression in HCC specimens including cancerous and noncancerous tissues. Associations of UHRF1 expression with demographic and clinicopathologic features in HCC were analyzed, and the effects of RNA interference of UHRF1 on cell proliferation, cell cycle, apoptosis, and migration were investigated in vitro and in vivo. UHRF1 mRNA and protein expression were both upregulated and negatively correlated with prognosis in HCC patients. Furthermore, inhibition of proliferation, migration, invasion, and epithelial-mesenchymal transition progression were observed in vitro and in vivo after UHRF1 knockdown, moreover, G2/M arrest was detected in HCC cells. In conclusion, elevated UHRF1 expression contributes to poor prognosis by promoting cell proliferation and metastasis in HCC.

[Positive circulating tumor cells in the peripheral blood may indicate a poor prognosis in patients with hepatocellular carcinoma].

OBJECTIVE: To assess the value of detecting peripheral blood circulating tumor cells (CTCs) in the diagnosis and treatment of hepatocellular carcinoma (HCC). METHODS: A total of 296 patients diagnosed with HCC admitted in our department from July 2013 to January 2015 were analyzed, with 39 patients with benign liver disease serving as the control group. The distribution of CTCs in the peripheral blood of HCC patients were detected by CanPatrol(TM) CTCs, and its relationship with the clinical features and prognosis of the patients were analyzed. RESULTS: s CTCs were detected in 64.5% (191/296) of the HCC patients but in none of the control group (P<0.05). Positive CTCs in peripheral blood of HCC patients were significantly correlated with serum AFP level, tumor number, TNM stage, BCLC stage, portal vein tumor thrombus and metastasis (P<0.05). In 127 HCC patients receiving radical surgery, the patients positive for CTCs showed significantly shorter relapse-free survival time (P<0.05). CONCLUSION: Positive CTCs in the peripheral blood may indicate a poor prognosis in HCC patients. CTCs may serve as a indicator for monitoring the prognosis of HCC.

Methylenetetrahydrofolate dehydrogenase 2 overexpression is associated with tumor aggressiveness and poor prognosis in hepatocellular carcinoma.

BACKGROUND: Methylenetetrahydrofolate dehydrogenase 2 (MTHFD2) is the key enzyme in the transformation of folic acid metabolites. MTHFD2 overexpression plays a key role in the progression of human cancers, and depletion of MTHFD2 has shown potential antitumor activities in several types of cancer. However, the role of MTHFD2 in hepatocellular carcinoma (HCC) has not been investigated. AIMS: To investigate the expression of MTHFD2 in HCC patients, and its associated clinical implications and possible functions in HCC. METHODS: Reverse transcription-polymerase chain reaction and immunohistochemical staining were used to detect MTHFD2 expression in liver tissues from HCC patients, then associations of MTHFD2 expression with demographic and clinicopathologic features were analysed. The effects of siRNA interference of MTHFD2 on cell proliferation, cell cycle, apoptosis, and migration were investigated in HCC cell lines. RESULTS: Significant overexpression of MTHFD2 was observed in HCC tissues, and overexpression of MTHFD2 was correlated with TNM stage, tumor microembolus, tumor metastasis, recurrence and the time of recurrence (P<0.05) in HCC patients. siRNA-mediated silencing of MTHFD2 inhibited migration, invasion and epithelial-mesenchymal transition progression in HCC cell lines, but no obvious effects on cell proliferation, apoptosis or cell cycle distribution were detected. CONCLUSIONS: MTHFD2 is overexpressed in HCC, and is associated with poor prognosis and cellular features connected to metastatic disease.

Dramatic antitumor effects of the dual mTORC1 and mTORC2 inhibitor AZD2014 in hepatocellular carcinoma.

The mammalian target of rapamycin (mTOR) has emerged as a critical effector in cell growth, proliferation, survival, angiogenesis, and autophagy through direct interaction with mTORC1 (mTOR complex 1) and mTORC2 (mTOR complex 2). The mTOR axis is aberrantly activated in about 50% of human hepatocellular carcinoma (HCC) cases and thus has become an attractive target for drug development in this disease. Allosteric inhibitors of mTORC1, rapamycin and its derivatives have been used to study in patients with HCC but have not shown significant clinical utility, likely because of the lack of inhibition of mTORC2. In the present study, we describe that AZD2014, a small molecular ATP-competitive inhibitor of mTOR, was a highly potent inhibitor of mTORC1 and mTORC2 in human HCC cells, which led to a more thorough inhibition of mTORC1 than rapamycin, and the inhibition of mTORC2 prevented the feedback activation of AKT signaling. Compared with rapamycin, AZD2014 resulted in more profound proliferation suppression, apoptosis, cell cycle arrest, and autophagy in HCC cells. Notably, we found blockage of both mTORC1 and mTORC2 by AZD2014 to be more efficacious than blockage of mTORC1 alone by rapamycin in inhibiting the migration, invasion and EMT progression of HCC cells. In conclusion, our current results highlight mechanistic differentiation between rapamycin and AZD2014 in targeting cancer cell proliferation, cell cycle, apoptosis, autophagy, migration, invasion and EMT progression, and provide support for further investigation of AZD2014 as an antitumor agent for the treatment of HCC in clinic.

[The preliminary study on the function of methylenetetrahydrofolate dehydrogenase 2 in hepatocellular carcinoma].

OBJECTIVE: To investigate the expression of methylenetetrahydrofolate dehydrogenase 2 (MTHFD2) in hepatocellular carcinoma (HCC) tissues and its correlation with clinical parameters. METHOD: Fluorogenic quantitative-polymerase chain reaction (FQ-PCR) was used to measure the MTHFD2 mRNA expression. The MTHFD2 protein expression was detected by immunohistochemical staining in cancerous tissues and adjacent noncancerous counterparts. The relationship of MTHFD2 expression, clinicopathological parameters and the prognosis of hepatocellular carcinoma was subsequently analysed. RESULTS: The MTHFD2 mRNA expression in cancerous tissues was higher than that in adjacent noncancerous counterparts (31/47) (P<0.05). The positive rate of MTHFD2 protein in cancerous tissues was significantly higher than that in adjacent noncancerous counterparts (69.5% vs. 33.9%) (P<0.05). MTHFD2 overexpression was found to correlate with clinical pathological parameters such as tumor metastasis, recurrence and poor prognosis (P<0.05). The patients with overexpressed MTHFD2 had shorter tumor-free survival time. CONCLUSIONS: Overexpression of MTHFD2 in HCC may be a risk factor of tumor metastasis and recurrence. MTHFD2 could be a new biomarker for prognosis of HCC.