HIF-1α In Hepatocellular Carcinoma Research Articles

BCLAF1-induced HIF-1α accumulation under normoxia enhances PD-L1 treatment resistances via BCLAF1-CUL3 complex

Bcl-2-associated transcription factor-1 (BCLAF1), an apoptosis-regulating protein of paramount significance, orchestrates the progression of various malignancies. This study reveals increased BCLAF1 expression in hepatocellular carcinoma (HCC) patients, in whom elevated BCLAF1 levels are linked to escalated tumor grades and diminished survival rates. Moreover, novel BCLAF1 expression is particularly increased in HCC patients who were not sensitive to the combined treatment of atezolizumab and bevacizumab, but not in patients who had tumors that responded to the combined regimen. Notably, overexpression of BCLAF1 increases HCC cell proliferation in vitro and in vivo, while the conditioned medium derived from cells overexpressing BCLAF1 strikingly enhances the tube-formation capacity of human umbilical vein endothelial cells. Furthermore, compelling evidence demonstrates that BCLAF1 attenuates the expression of prolyl hydroxylase domain protein 2 (PHD2) and governs the stability of hypoxia-inducible factor-1α (HIF-1α) under normoxic conditions without exerting any influence on transcription, as determined by Western blot and RT‒qPCR analyses. Subsequently, employing coimmunoprecipitation and immunofluorescence, we validated the reciprocal interaction between BCLAF1 and Cullin 3 (CUL3), through which BCLAF1 actively upregulates the ubiquitination and degradation of PHD2. The Western blot and RT‒qPCR results suggests that programmed death ligand-1 (PD-L1) is one of the downstream responders to HIF-1α in HCC. Thus, we reveal the pivotal role of BCLAF1 in promoting PD-L1 transcription and, through binding to CUL3, in promoting the accumulation of HIF-1α under normoxic conditions, thereby facilitating the ubiquitination and degradation of PHD2.

B-364 Inhibition of Hypoxia-Inducible Factor-1a (HIF-1 a) Provides a Therapeutic Approach for Hepatocellular Carcinoma (HCC)

Abstract Background The most frequent type of primary liver cancer in adults is hepatocellular carcinoma (HCC) which is the third-highest cause of cancer-related death worldwide. Globally, people die from liver cancer each year, with HCC accounting for around 90% of those deaths, making it a serious public health concern. Cirrhosis, hepatitis B, hepatitis C, and non-alcoholic fatty liver disease are all high-risk factors for HCC development. In addition, HCC is one of the most frequent solid tumors found in humans. Due to insufficient blood supply, these solid tumors usually are devoid of oxygen and nutrients. A reduction in oxygen concentration results in the formation of a hypoxic environment that downregulates the metabolic process and is fatal to cancer cells. To circumvent this barrier to growth, cancer cells produce hypoxia-inducible factor-1 (HIF-1), which alters their metabolic pathways and allows them to survive. HIF-1alpha (HIF-1α), a cytoplasmic subunit of HIF-1 can be overexpressed in hypoxic conditions. HCC cells cannot proliferate under hypoxia without a high level of HIF-1α expression, making it as a potential cancer treatment target. Using the LOPAC (Library of Pharmacologically Active Compounds) drug library, we have identified multiple drug molecules that inhibit the expression of HIF-1α. Methods We constructed specific SK-HEP-1 cells, a human liver cancer cell line, expressing the luciferase reporter gene under the promoter of HIF-1α. By using the cells, we screened the (LOPAC) library. Other bioanalytical methods were used to confirm and analyze identified candidates. Results We successfully identified several compounds that are able to inhibit HIF-1α expression by using luciferase activity assays and Western blot analysis (WB). Further investigation was conducted to determine the molecular mechanism and function for one of the drug candidates, termed as UZ-1, in inhibiting HIF-1α in HCC by using the MTT assay and WB. UZ-1, an antirheumatic agent, showed a strong inhibitory effect on the expression of HIF-1α in SK-HEP-1 cells. In addition, it suppressed the signaling pathways associated with HIF-1α, leading to the apoptosis of HCC cells. Conclusion The UZ-1 molecule inhibits HIF-1α expression, as a result, and displays anticancer function in HCC cells through inducing apoptosis. Our result suggests that UZ-1 may be a potential drug candidate for the treatment of HCC.

Targeting Hypoxia-Inducible Factor-1α for the Management of Hepatocellular Carcinoma.

Hypoxia-inducible factor 1 alpha (HIF-1α) is a transcription factor that regulates the cellular response to hypoxia and is upregulated in all types of solid tumor, leading to tumor angiogenesis, growth, and resistance to therapy. Hepatocellular carcinoma (HCC) is a highly vascular tumor, as well as a hypoxic tumor, due to the liver being a relatively hypoxic environment compared to other organs. Trans-arterial chemoembolization (TACE) and trans-arterial embolization (TAE) are locoregional therapies that are part of the treatment guidelines for HCC but can also exacerbate hypoxia in tumors, as seen with HIF-1α upregulation post-hepatic embolization. Hypoxia-activated prodrugs (HAPs) are a novel class of anticancer agent that are selectively activated under hypoxic conditions, potentially allowing for the targeted treatment of hypoxic HCC. Early studies targeting hypoxia show promising results; however, further research is needed to understand the effects of HAPs in combination with embolization in the treatment of HCC. This review aims to summarize current knowledge on the role of hypoxia and HIF-1α in HCC, as well as the potential of HAPs and liver-directed embolization.

Hypoxia‑inducible factor‑1α: A critical target for inhibiting the metastasis of hepatocellular carcinoma (Review)

Metastasis is one of the major reasons for patient mortality in hepatocellular carcinoma (HCC), and the progression of HCC to a metastatic state depends on the local microenvironment. Hypoxia is a key condition affecting the microenvironment of HCC. Currently, various studies have shown that the expression of hypoxia-ainducible factor-1α (HIF-1α) is associated with the invasion and metastasis of HCC. High expression of HIF-1α often leads to poor prognosis in patients with HCC. In this review, the molecular structure of HIF-1α is described, and the expression pattern of HIF-1α in HCC under hypoxia, which is associated with metastasis and poor prognosis in HCC, is explained. The molecular mechanisms of HIF-1α function and the metastasis of HCC are further discussed. The modulation of HIF-1α can reduce sorafenib resistance and improve the prognosis of patients after TACE. Therefore, HIF-1α may be a critical target for inhibiting HCC metastasis in the future.

Effects of hypoxia-inducible factor-1α and hypoxia-inducible factor-2α overexpression on hepatocellular carcinoma survival: A systematic review with meta-analysis.

The role of hypoxia-inducible factor-1α (HIF-1α) and hypoxia-inducible factor-2α (HIF-2α) has been implicated in the clinical prognosis of hepatocellular carcinoma (HCC), but the results remain controversial. We aim to investigate the association of HIF-1α and HIF-2α overexpression with the prognosis and clinicopathological features of HCC. A systematic search was conducted in PubMed, Embase, Scopus, Web of Science, and Cochrane Library until June 20, 2020. Meta-analysis was conducted to generate combined HRs with 95% confidence intervals (CI) for overall survival (OS) and disease-free survival (DFS). Odds ratios (ORs) with 95% CI were also derived by fixed or random effect model. Twenty-two studies involving 3238 patients were included. Combined data suggested that overexpression of HIF-1α in HCC was not only correlated with poorer OS [HR=1.75 (95% CI: 1.53-2.00)] and DFS [HR=1.64 (95% CI: 1.34-2.00)] but was also positively associated with vascular invasion [OR=1.83 (95% CI: 1.36-2.48)], tumor size [OR=1.36 (95% CI: 1.12-1.66)], and tumor number [1.74 (95% CI: 1.34-2.25)]. In contrast, HIF-2α overexpression was not associated with the prognosis and clinicopathological features of HCC. Our data provided compelling evidence of a worse prognosis of HCC in HIF-1α overexpression patients but not HIF-2α overexpression ones.

Dishevelled Associated Activator Of Morphogenesis (DAAM) Facilitates Invasion of Hepatocellular Carcinoma by Upregulating Hypoxia-Inducible Factor 1α (HIF-1α) Expression.

BackgroundThe dishevelled associated activator of morphogenesis (DAAM) family, consisting of DAAM1 and DAAM2, is an important component of the Wnt signal pathway. Previous studies have suggested that DAAM2 reduces Von Hippel-Lindau (VHL) expression by promoting its ubiquitination, but the correlation between DAAM and HIF-1α in hepatocellular carcinoma (HCC) has not been studied.Material/MethodsIn our study, expression of DAAM1 and DAAM2 in HCCs and tumor-adjacent liver tissues was assessed with qRT-PCR and immunohistochemistry. Correlations between DAAM1/2 and the clinicopathologic variables were evaluated with the Chi-square test. With univariate and multivariate analysis, we further evaluated the prognostic significance of DAAM1 and DAAM2. Using in vitro experiments, we assessed the functions of DAAM1 and DAAM2 in invasion and proliferation in different HCC cell lines and investigated their underlying mechanisms.ResultsDAAM1 and 2 overexpression were 18.8% and 48.7%, respectively, of the whole cohort. mRNAs of DAAM2 in HCCs were substantially higher than mRNAs in liver tissues, while DAAM1 mRNA had no marked difference. High DAAM2 expression was notably associated with advanced T stage (P=0.032), TNM stage (P=0.032), and overall survival (OS) rate (P=0.004). DAAM 2 knockdown promoted VHL accumulation and subsequent HIF-1α down-regulation in HCC cells. In HCC specimens, DAAM2 expression was also negatively correlated with VHL and positively associated with HIF-1α. Moreover, HIF-1α was required in DAAM2-induced invasion of HCC cells.ConclusionsDAAM2, rather than DAAM1, was able to predict prognosis of HCC. DAAM2 decreased VHL expression and consequently upregulated HIF-1α, eventually facilitating invasion of HCC.

Prognostic and diagnostic role of VEGF-A and HIF-1α in hepatocellular carcinoma treated with chemoembolization

INTRODUCTION: Hepatocellular carcinoma (HCC), the most common primary liver cancer, is characterized by almost equal incidence and mortality, due to late diagnosis, inadequate therapies and complex mechanisms of carcinogenesis. In hepatocarcinogenesis neo-angiogenesis plays an important role, to such an extent that it is considered as a possible therapy-target.

Hypoxia inducible factor 1α in hepatocellular carcinoma with cirrhosis: Association with prognosis

BackgroundHypoxia inducible factor 1α (HIF-1α) is a protein related with carcinogenesis and metastasis in many tumors. However, little is known about the prognostic value of HIF-1α in hepatocellular carcinoma (HCC) patients with cirrhosis. MethodsClinical-pathological information and follow-up data were collected from HCC (n = 419) and chronic hepatitis (n = 49) patients. HIF-1α expression was scored based on the percentage of immunohistochemical staining. Correlations between HIF-1α expression and clinical features were evaluated by Chi-square test. And survival analysis was performed by multivariate Cox regression analysis. ResultsIn cirrhosis patients, the frequency of HIF-1α positive expression in HCC was higher than in chronic hepatitis (P = 0.002). HIF-1α positive expression was significantly associated with vascular invasion (P = 0.002), TNM stage (P = 0.005), HBV infection (P = 0.005), tumor size (P = 0.025) and portal vein tumor thrombus (P = 0.001) in HCC with liver cirrhosis. While, in cirrhosis-free patients, HIF-1α positive expression had a significant correlation with vascular invasion (P = 0.039) and AFP value (P = 0.001) in. HIF-1α “positive” had decreased overall survival compared to HIF-1α “negative” patients and this was an independent adverse prognostic factor (multivariable analysis P = 0.001) for HCC patients with cirrhosis, but not for cirrhosis-free patients. ConclusionsOur results suggested that HIF-1α served as a poor prognostic factor for HCC patients with cirrhosis.

Association of PD-L1 and HIF-1α Coexpression with Poor Prognosis in Hepatocellular Carcinoma

OBJECTIVE: To investigate the correlation between the expression of PD-L1 and HIF-1α in hepatocellular carcinoma (HCC) tissue and further analyze the association with clinical parameters and the prognostic value of coexpression in HCC patients. METHODS: We assessed the expression of PD-L1 and HIF-1α by immunohistochemistry in tumor tissue from 90 HCC patients who underwent curative hepatectomy. The results were validated in an independent cohort of additional 90 HCC patients. RESULTS: PD-L1 and HIF-1α exhibited in tumor tissue high expression rates of 41.11% (37/90) and 43.33% (43/90), respectively, and their expressions were positively correlated (r = 0.563, P < .01). High expression of PD-L1 was significantly associated with low albumin levels (P < .05); high expression of HIF-1α was significantly correlated with high alpha-fetoprotein (AFP) levels and low albumin levels (P < .05); high expression of both PD-L1 and HIF-1α was also significantly associated with high AFP levels and low albumin levels (P < .05). High expression of PD-L1, HIF-1α, as well as both PD-L1 and HIF-1 α was respectively significantly associated with worse overall survival (OS) and disease-free survival (DFS) (P < .05). Patients with co-overexpression of PD-L1 and HIF-1α had the worst prognosis compared with other groups. Additionally, multivariate Cox regression models suggested that high expression of PD-L1, HIF-1α, as well as both PD-L1 and HIF-1α was an independent prognostic factor for OS and DFS (P < .05). Furthermore, the positive correlation and prognostic values of PD-L1 and HIF-1α were validated in an independent data set. CONCLUSION: We demonstrated that HCC patients with co-overexpression of PD-L1 and HIF-1α in tumor tissue had a significantly higher risk of recurrence or metastasis and death compared with others. Therefore, more frequent follow-up is needed for patients with co-overexpression of PD-L1 and HIF-1α. At the same time, a combinational therapy with HIF-1α inhibitors in conjunction with PD-L1 blockade may be beneficial for HCC patients with co-overexpression in the future.

Metformin suppresses hypoxia-induced stabilization of HIF-1α through reprogramming of oxygen metabolism in hepatocellular carcinoma.

Overexpression of hypoxia-induced factor 1α (HIF-1α) has been shown to be involved in the development and progression of hepatocellular carcinoma (HCC). HIF-1α should therefore be a promising molecular target for the development of anti-HCC agents. Metformin, an established antidiabetic drug, has proved to also be effective in treating cancer although the precise underlying mechanisms of this activity are not fully elucidated. The aim of this study was to investigate the effects of metformin on the expression of HIF-1α and oxygen metabolism in HCC. The results showed that metformin inhibited hypoxia-induced HIF-1α accumulation and activation independent of AMP-activated protein kinase (AMPK). Moreover, this decrease in HIF-1α accumulation was accompanied by promotion of HIF-1α protein degradation. In addition, metformin significantly decreased oxygen consumption, ultimately leading to increased intracellular oxygen tension and decreased staining with the hypoxia marker pimonidazole. In vivo studies demonstrated that metformin delayed tumor growth and attenuated the expression of HIF-1α in HCC tumor xenografts. Together, these findings suggest that metformin decreases hypoxia-induced HIF-1α accumulation by actively suppressing mitochondrial oxygen consumption and enhancing cellular oxygenation ability, providing a fundamental mechanism of metformin activity against HCC.

Correlations between ADC values and molecular markers of Ki-67 and HIF-1α in hepatocellular carcinoma

ObjectiveHepatocellular carcinoma (HCC) is the third leading cause of cancer-related deaths. Cell proliferativity and hypoxia have important impact on the response to radiotherapy or chemotherapy. The purpose of this study was to investigate the association of apparent diffusion coefficient (ADC) values and the molecular markers Ki-67 and hypoxia inducible factor-α (HIF-α) in hepatocellular carcinoma (HCC). Materials and methodsForty-seven patients diagnosed with HCC were included in this study. All patients performed diffusion-weighted magnetic resonance imaging (DW-MRI) before any anticancer treatment. The ADC maps were automatically calculated on a Syngo workstation. The Ki-67 and HIF-1α expression were assessed by immunohistochemistry. The Pearson correlation test was used to assess the correlation between ADC values and Ki-67 and HIF-1α expression. ResultsKi-67 staining was clearly identified based on the brown nuclear staining in tumor cells. High Ki-67 expression was correlated with low differentiation (p=0.028). A significant correlation was observed between HIF-1α expression and maximum diameter (p=0.014). The mean ADC value was (0.983±0.21)×10−3mm2/s. The level of Ki-67 expression was correlated inversely with the ADC values (r=−0.371, p=0.01). There was a significant positive correlation between the ADC values and HIF-1α expression (r=0.389, p=0.007). ConclusionThe ADC values were observed to correlate significantly with the molecular markers Ki-67 and HIF-1α. Our results suggest that the ADC values on DW-MRI may be used as a measure of cell proliferativity and hypoxia in hepatocellular carcinoma.

Hypoxia inducible factor in hepatocellular carcinoma: A therapeutic target.

Hepatocellular carcinoma (HCC) is one of the most commonly diagnosed and deadly cancers worldwide; its incidence has been rising in the United States due to the increase in hepatitis C associated cirrhosis and the growing epidemic of obesity. There have been no effective therapeutic options in the advanced disease setting beyond sorafenib, a multi-targeted tyrosine kinase inhibitor that showed significant survival benefit. Because of this, there is an urgent need to search for novel pathways in sorafenib experienced patients. This review will focus on the role of hypoxia and hypoxia-inducible factor alpha (HIF-1α) in cancer development, specifically in HCC. We will discuss the biology of HIF-1α, the pathways with which it interacts, and the function of HIF-1α in HCC. Furthermore, we will review studies highlighting the relevance of HIF-1α in the clinical setting, as well as the pre-clinical data supporting its further investigation. Finally, we will conclude with a discussion of the potential role of a HIF-1α mRNA antagonist for the treatment of HCC, and hypothesize the ways in which such an inhibitor may be best utilized in the management of advanced HCC. Hypoxia plays a significant role in the development of HCC. HIF-1α is a key transcription factor involved in the hypoxic response of cancer cells. It activates transcription of genes responsible for angiogenesis, glucose metabolism, proliferation, invasion and metastasis in HCC. Its involvement in multiple, essential tumor pathways makes it an attractive potential therapeutic target in HCC.

Expression and significance of MMP2 and HIF-1α in hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) is a serious threat to human health. HCC is a malignant tumor and its invasion and metastasis are the result of multigene interactions. Matrix metalloproteinase-2 (MMP-2) is capable of degrading the majority of components of the extracellular matrix and is regarded to closely correlate with tumor invasion and metastasis. Furthermore, the hypoxia-inducible factor 1α (HIF-1α) is an important transcription factor, which is closely associated with the process of tumor growth. The aim of the present study was to investigate the expression of MMP2 and HIF-1α) in HCC, and the relationship between MMP2/HIF-1α protein expression and the clinical/pathological characteristics of HCC. The mRNA levels of MMP2 and HIF-1α were detected in 32 cases of HCC and the corresponding normal adjacent tissues with fluorescence-based quantitative polymerase chain reaction (qPCR). The protein expression of MMP2 and HIF-1α was assessed in 45 HCC cases and 33 cases of corresponding normal adjacent tissue, using immunohistochemical methods. The association between MMP2/HIF-1α and pathological features of HCC, and the correlation between MMP2 and HIF-1α were analyzed. The Kaplan-Meier method was used to assess the impact of MMP2 and HIF-1α expression on survival. The fluorescence-based qPCR demonstrated that MMP2 and HIF-1α mRNA expression levels in the HCC tissues were 0.84±0.17 and 0.87±0.11, respectively, which were significantly higher than those in the adjacent normal tissues (0.70±0.13 and 0.68±0.13, respectively; P<0.05). Immunohistochemical analysis revealed that MMP2 and HIF-1α protein expression in the HCC tissues was 63.1 and 70.8%, respectively, which was also higher than that in the adjacent normal tissues (34.2 and 36.8%, respectively). There was no significant correlation between the expression of MMP2 or HIF-1α protein and the age or gender of patients with HCC (P>0.05). However, there was significant correlation between MMP2 or HIF-1α protein expression and tumor size, metastasis, presence of a capsule and clinical TNM staging of HCC. Their expression also had a significant effect on patient survival time. In conclusion, MMP2 and HIF-1α are overexpressed in HCC, and the MMP2 signaling pathway may promote the development of HCC together with HIF-1α.

Relationship between blood flow assessed by ultrasound, MVD and expression of HIF-1α in hepatocellular carcinoma

AIM: To investigate the ultrasonic signs of hepatocellular carcinoma (HCC), the expression of hypoxia inducible factor-1 alpha (HIF-1α) and microvessel density (MVD), and to analyze their correlations. METHODS: Sixty patients who underwent duplex sonography and color Doppler ultrasonography before surgery and were surgically proved to have HCC were included. Immunohistochemical method was used to detect the wcjd@wjgnet.com 世界华人消化杂志 2014年4月18日; 22(11): 1587-1591 ISSN 1009-3079 (print) ISSN 2219-2859 (online) 临床经验 CLINICAL PRACTICE 超声检测肝癌血流分级及其与HIF-1α、MVD表达的关系

Expression of HIF-1α in hepatocellular carcinoma and its relationship with vasculogenic mimicry and clinical pathology

The aim of this study was to discuss HIF-1α expression and vasculogenic mimicry (VM) in hepatocellular carcinoma (HCC) and their relationship with the clinical pathological features and clinical significance. Two hundred and seven specimens from patients in The Affiliated Hospital of North Sichuan Medical College who received hepatic cell carcinoma resection were tested by immunohistochemistry and double staining of CD31 and PSA. Then detected the expression of HIF-1α, VM, and analysed the relationship between clinical pathology. The HIF-1α positive rate was 71.01% and its expression was associated with liver cirrhosis, tumor size and TNM stage (P < 0.05). HIF-1α protein expression was positively associated with the VM (γ = 0.1988, P = 0.0041). Hypoxia may be the reason for VM in high invasive HCC, regulating the tumor microenvironment may have great significance in inhibiting invasion and metastasis of HCC.

Hypoxia-induced overexpression of DEC1 is regulated by HIF-1α in hepatocellular carcinoma

Hypoxia-inducible factor-1α (HIF-1α) and differentiated embryo-chondrocyte expressed gene 1 (DEC1) are two key factors that protect hepatocellular carcinoma (HCC) cells from a hypoxic microenvironment. However, little is known concerning the effects of hypoxia on the expression of HIF-1α and DEC1 in HCC. In the present study, RT-PCR and western blotting were conducted to assay the mRNA and protein levels of HIF-1α and DEC1 under normoxia and hypoxia induced by exposure to CoCl2 for different time periods (0, 2, 4, 6, 24 and 48 h). In addition, the HIF-1α protein inhibitor, YC-1, was used to analyze the interaction between DEC1 and HIF-1α expression and the related mechanism. Results showed that expression of DEC1 in HCC was significantly upregulated at both the mRNA and protein levels, when compared with that in normal liver cells (P<0.05). Hypoxia induced the upregulation of HIF-1α in a time-dependent manner, which was also observed at the DEC1 mRNA and protein levels (P<0.05). However, hypoxia did not affect the transcription of HIF-1α (P>0.05). A positive correlation was found between HIF-1α and DEC1 expression in both BEL-7402 (r=0.885, P<0.05) and SMMC-7721 cells (r=0.826, P<0.05). Furthermore, inhibition of HIF-1α by YC-1 led to a significant decrease in DEC1 induced by hypoxia (P<0.05). We suggest that hypoxia induced the overexpression of DEC1, the mechanism of which may be related to the upregulation of HIF-1α in HCC. The efficacy of inhibiting HIF-1α and DEC1 expression as a possible treatment for HCC should be assessed in clinical trials.

The Expression and Clinical Significance of Omi/Htra2 in Hepatocellular Carcinoma

To investigate Omi/HtrA2 expression and its clinical significance in hepatocellular carcinoma. We analyzed Omi/HtrA2 expression in hepatocellular carcinoma, paracancerous tissues and normal hepatic tissues by immunohistochemistry, RT-PCR and Western blot. Hypoxia-inducible factor-1α (HIF-1α) expression was also detected in hepatocellular carcinoma samples by immunohistochemistry. Meanwhile, we retrospectively analyzed the relationship between Omi/HtrA2 expression and the survival times of the patients. We found that Omi/HtrA2 overexpressed in hepatocellular carcinoma and was correlated with hepatocellular carcinoma differentiation, tumor size, portal vein invasion, clinical stage and lymph node metastasis. We also observed a significant inverse correlation between the expression of Omi,/HtrA2 and HIF-1α in hepatocellular carcinoma. The Kaplan-Meier estimates showed that patients who were Omi/HtrA2 positive had much longer survival times than those who were Omi/HtrA2 negative. Both univariate and multivariate analysis using the Cox regression model indicated that Omi/HtrA2 expression was a significant factor for prognosis. Hepatocellular carcinoma cells may need Omi/HtrA2 expression for apoptosis and Omi/HtrA2 might be an important prognostic marker for primary hepatocellular carcinoma.

Underexpressed microRNA‐199b‐5p targets Hypoxia‐Inducible Factor‐1α in hepatocellular carcinoma and predicts prognosis of hepatocellular carcinoma patients

MicroRNAs are short noncoding RNA molecules that are responsible for the posttranscriptional regulation of target genes. The aim of this study was to determine whether microRNA-199b-5p (miR-199b) plays a role in the progression and prognosis of hepatocellular carcinoma (HCC), and to elucidate whether hypoxia-inducible factor-1α (Hif1α) is regulated by miR-199b. In this study, 35 matched HCCs and cirrhosis tissues were assayed for miR-199b and Hif1α expression. To evaluate the role of miR-199b, we assessed cell proliferation rate and clonogenic survival of miR-199b- or negative control-transfected cells by MTT and clone formation assay, respectively. In addition, the regulation of Hif1α by miR-199b was evaluated by Western blotting and luciferase assay. MiR-199b was downregulated in 77% of HCCs, whereas Hif1α protein was upregulated in 69% of cases. A significant inverse correlation between miR-199b and Hif1α was observed in HCCs. Patients with lower levels of miR-199b expression had poorer overall survival and progression-free survival rates, whereas patients with higher levels of miR-199b expression had better survival. Moreover, miR-199b could restrain cell growth and obviously enhance the radiosensitizing effect of HepG2 cells. MiR-199b and pGL3-Hif1α vector-transfected cells showed suppressed Hif1α protein expression and significant reduced luciferase activity. Underexpressed miR-199b, which may be via the upregulation of Hif1α in HCCs, is inversely correlated with survival and directly correlated with the malignant status of HCC patients.

Study on the expression of Glut1, HIF-1α and Ki-67 in hepatocellular carcinoma and their relationship

Objective To explore the expression of Glut1, HIF-1α and Ki-67 in hepatocellular carcinoma (HCC) and their relationship between their expression and clinicopathological features.Methods Immunohistochemical study (EnVision method) for Glut1, HIF-1a and Ki-67 were performed on tissue microarray which consisted of 171 cases of HCC, 55 cases of adjacent non-neoplastic liver tissues, and 22cases of normal liver tissues.Results The expression rate of Glut1 ,HIF-1α and ki-67 in 171 cases of HCC was 15.2％, 19.9％ and 66.1％, respectively, which was much higher than that in the adjacent non-neoplastic liver tissues (1.8％ ,1.8％and 5.5％) and normal liver tissues(all negative).The expressions of Glut1 and HIF-1α were positively correlated with the differentiation degree of HCC and TNM stage(P ＜0.01, P ＜0.05).The expression of ki-67 was positively correlated with the differentiation degree of HCC.There was a significant positive correlation between the expressions of Glut1 and HIF-1α in HCC (r1 =0.553, P ＜0.05), the expressions of Glut1 and HIF-1α were positively correlated with ki-67(r2 =0.560,r3 =0.613, P ＜0.05).Conclusions Glut1, HIF-1α and ki-67 may play a role in the tumorigenesis and progression of HCC in some degree.Combined detection of Glut1, HIF-1α and Ki-67 may be helpful to judge the degree of malignancy and potential metastasis and evaluate the prognosis. Key words: Glucose transport proteins,facilitative/ME,Hypoxia-inducible factor 1/ME; Ki-67antigen/ME; Carcinoma, hepatocellular/ME

Activation of β-Catenin by Hypoxia in Hepatocellular Carcinoma Contributes to Enhanced Metastatic Potential and Poor Prognosis

Aberrant activation of beta-catenin contributes to the malignant phenotype in hepatocellular carcinoma (HCC). Hypoxia is also known to promote HCC invasion and metastasis. However, the association between beta-catenin and the proinvasive role of hypoxia remains unclear. We investigated the role of beta-catenin in the proinvasive consequences of hypoxia in HCC. We established in vitro and in vivo hypoxic models to investigate the expression of beta-catenin in hypoxic HCC cells and its role in hypoxia-induced aggressiveness. The clinical significance of beta-catenin and/or hypoxia-induced factor-1alpha (HIF-1alpha) was evaluated using HCC tissue microarrays. Hypoxia induced beta-catenin overexpression and/or intracellular accumulation in four HCC cell lines through downregulating the endogenous degradation machinery, and promoted in vitro invasion and in vivo metastasis of MHCC97 and Hep3B cells. Besides morphologic changes, hypoxic MHCC97 and Hep3B cells exhibited molecular alterations consistent with epithelial-mesenchymal transition, characterized by the loss of epithelial cell markers (E-cadherin and plakoglobin) and upregulation of mesenchymal markers (vimentin and N-cadherin), as well as the increase of matrix metalloproteinase 2. However, silencing beta-catenin in these hypoxic cells reversed epithelial-mesenchymal transition and repressed metastatic potential. Positive expression of beta-catenin in HCC tissue microarray was associated with the expression of HIF-1alpha (P=0.034), and coexpression of beta-catenin and HIF-1alpha in HCC was correlated with shorter overall survival and time to recurrence. beta-Catenin in HCC is activated by hypoxia and contributes to hypoxia-induced metastatic potential.