Alteration of oncogenic IGF-II gene methylation status associates with hepatocyte malignant transformation.

BACKGROUND: Oncogenic insulin-like growth factor-II (IGF-II) is overexpressed in hepatocellular carcinoma (HCC). The present study aimed to analyze the dynamic alteration of IGF-II CpG site methylation status and its molecular mechanism in HCC progression. METHODS: IGF-II alterations were observed in rat hepatocarcinogenesis models induced by 2-acetylaminofluorene. Liver IGF-II expression was compared by immunohistochemistry or tissue IGF-II specific concentration (nmol/mg protein). Status of human IGF-II promoter 3 (P3) or rat IGF-II P2 CpG site methylation was amplified by methylation-specific polymerase chain reaction (MSP). Serum IGF-II levels were quantitatively detected by an enzyme-linked immunosorbent assay. RESULTS: The levels of hepatic IGF-II expression were significantly elevated in the HCC group (P < 0.001). The unmethylation rate of IGF-II P3 CpG sites was 100% in the HCC-, 52.5% in the paracancerous-, and none (0%) in the distal noncancerous-tissues. Abnormal IGF-II expression was related to differentiation degree, tumor invasion, and positive HBV-DNA (all P < 0.001), with a negative correlation between P3 methylation degree and IGF-II expression. There was a positive correlation between liver IGF-II specific concentration and circulating IGF-II level (r = 0.97, P < 0.001). Significantly negative correlation was found between IGF-II P2 CpG site methylation and circulating IGF-II (rs = -0.89, P < 0.001) or liver IGF-II level (rs = -0.84, P < 0.001). CONCLUSIONS: The increase of serum IGF-II and the alteration of oncogenic gene IGF-II methylation may be biomarkers for HCC diagnosis and DNA methylation may be the therapeutic target of HCC.

Abnormal expression of HMGB-3 is significantly associated with malignant transformation of hepatocytes.

AIM: To explore the relationship between dynamic expression of high mobility group box-3 (HMGB3) and malignant transformation of hepatocytes. METHODS: Expression of HMGB family proteins were observed in rat hepatocarcinogenesis models induced with 2-acetylaminofluorene. Alterations of HMGB3 were analyzed at the mRNA level by reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and at the protein level by immunohistochemistry or Western blotting. HMGB3 in human liver cancer tissues were evaluated using bioinformatics databases from GEO, TCGA, and Oncomine. A specific HMGB3-shRNA was used to knock down HMGB3 expression in order to investigate its effects on proliferation and cell cycle in vitro and in vivo. RESULTS: Elevated HMGB3 levels were first reported in hepatocarcinogenesis, with increasing expression from normal liver to cancer. Bioinformatic databases showed that HMGB3 expression in hepatocellular carcinoma tissues was significantly higher than that in normal liver tissues. Higher HMGB3 expression was discovered in liver cancer cells compared with LO2 cells in vitro. According to gene set enrichment analysis, HMGB3 mRNA levels were correlated with cell cycle and DNA replication pathways. Knocking down HMGB3 by specific shRNA significantly inhibited proliferation of HepG2 cells by cell cycle arrest and downregulating DNA replication related genes (cyclin B1, FEN1, and PCNA) at the mRNA and protein level. Furthermore, silencing HMGB3 significantly inhibited xenograft tumor growth (measured by Ki67) in vivo. CONCLUSION: HMGB3 is involved in malignant transformation of hepatocytes and could be a useful biomarker for diagnosis and a potential target for therapy of liver cancer.

Expression of hepatic Wnt5a and its clinicopathological features in patients with hepatocellular carcinoma.

BACKGROUD: Wingless-type MMTV integration site family member 5a (Wnt5a) is involved in carcinogenesis. However, little data are available in Wnt5a signaling with hepatocellular carcinoma (HCC). In the present study, we investigated the expression of hepatic Wnt5a in HCC and the role of Wnt5a in HCC progression and outcome. METHODS: Wnt5a expression and cellular distribution in HCCs and their matched paracancerous tissues from 87 patients were analyzed with tissue microarray and immunohistochemistry and compared with hepatic Wnt3a signaling. Wnt5a expression was categorized into low or high based on immunohistochemistry. Overall survival rate of HCC patients was estimated in correlation with the hepatic Wnt5a level using Kaplan-Meier method; the survival difference between patients with low and those with high Wnt5a was compared with log-rank test; and prognostic analysis was carried out with Cox regression. RESULTS: Total incidence of Wnt5a expression in the HCC tissues was 70.1%, which was significantly lower (χ2 = 13.585, P < 0.001) than that in their paracancerous tissues (88.5%). Significant difference of Wnt5a intensity was found between HCC and their paracancerous tissues (Z = 8.463, P < 0.001). Wnt5a intensity was inversely correlated with Wnt3a signaling (r = -0.402, P < 0.001) in HCC tissues. A decrease of Wnt5a expression in relation to the clinical staging from stage I to IV and low or no staining at advanced HCC were observed. Wnt5a level was related to periportal embolus (χ2 = 11.069, P < 0.001), TNM staging (χ2 = 8.852, P < 0.05), 5-year survival (χ2 = 4.961, P < 0.05), and confirmed as an independent prognosis factor of HCC patients (hazard ratio: 1.957; 95% confidence interval: 1.109-3.456; P < 0.05). CONCLUSIONS: The decrease of hepatic Wnt5a signaling is associated with HCC progression and poor prognosis.

Overexpression of insulin-like growth factor-I†receptor as a pertinent biomarker for hepatocytes malignant transformation.

AIM: To investigate the dynamic features of insulin-like growth factor-I receptor (IGF-IR) expression in rat hepatocarcinogenesis, and the relationship between IGF-IR and hepatocytes malignant transformation at mRNA or protein level. METHODS: Hepatoma models were made by inducing with 2-fluorenylacetamide (2-FAA) on male Sprague-Dawley rats. Morphological changes of hepatocytes were observed by pathological Hematoxylin and eosin staining, the dynamic expressions of liver and serum IGF-IR were quantitatively analyzed by an enzyme-linked immunosorbent assay. The distribution of hepatic IGF-IR was located by immunohistochemistry. The fragments of IGF-IR gene were amplified by reverse transcription-polymerase chain reaction, and confirmed by sequencing. RESULTS: Rat hepatocytes after induced by 2-FAA were changed dynamically from granule-like degeneration, precancerous to hepatoma formation with the progressing increasing of hepatic mRNA or IGF-IR expression. The incidences of liver IGF-IR, IGF-IR mRNA, specific IGF-IR concentration (ng/mg wet liver), and serum IGF-IR level (ng/mL) were 0.0%, 0.0%, 0.63 ± 0.17, and 1.33 ± 0.47 in the control; 50.0%, 61.1%, 0.65 ± 0.2, and 1.51 ± 0.46 in the degeneration; 88.9%, 100%, 0.66 ± 0.14, and 1.92 ± 0.29 in the precancerosis; and 100%, 100%, 0.96 ± 0.09, and 2.43 ± 0.57 in the cancerous group, respectively. IGF-IR expression in the cancerous group was significantly higher (P < 0.01) than that in any of other groups at mRNA or protein level. The closely positive IGF-IR relationship was found between livers and sera (r = 0.91, t = 14.222, P < 0.01), respectively. CONCLUSION: IGF-IR expression may participate in rat hepatocarcinogenesis and its abnormality should be an early marker for hepatocytes malignant transformation.

[Short hairpin RNA mediated glypican-3 silencing inhibits hepatoma cell invasiveness and disrupts molecular pathways of angiogenesis].

OBJECTIVE: To construct glypican-3 (GPC-3) short hairpin RNA (shRNA) and investigate the effects of GPC-3 transcription silencing on hepatoma cell invasion and angiogenesis mechanisms. METHODS: GPC-3-specific shRNA and non-target control shRNA were constructed and transfected into the human hepatoma cell lines HepG2, MHCC-97H, and Huh7. shRNA-mediated silencing of GPC-3 expression was confirmed at the mRNA and protein levels by fluorescence quantitative reverse transcription (FQRT)-PCR and western blotting, respectively. The effect of silenced GPC-3 expression on cell proliferation was detected by EdU and sulforhodamine B assays, on migration by wound healing (scratch) assay, on invasion by transwell chamber assay, and on apoptosis by luminescence assay of caspase-3/7 activity. The effect of silenced GPC-3 expression on angiogenesis-related signaling factors was detected by FQRT-PCR (for the glioma-associated oncogene homolog-1 hedgehog signaling factor, GLI1, and the beta-catenin Wnt signaling factor, b-catenin), immunofluorescent staining (for the insulin-like growth factor-II, IGF-II), and ELISA (for the vascular endothelial growth factor, VEGF). Pairwise comparisons were made by the independent sample t-test, and multiple comparisons were made by one-way ANOVA. RESULTS: In all cell lines, transfection with the GPC-3-specific shRNA significantly reduced GPC-3 mRNA levels (% reduction as compared to the non-target control shRNA: HepG2, 89.2+/-6.0%, t = -25.753, P less than 0.001; MHCC-97H, 75.3+/-4.9%, t = -26.487, P less than 0.001; Huh7, 73.6+/-4.6%, t = -27.607, P less than 0.001); the GPC-3 protein levels were similarly reduced. The GPC-3 shRNA-silenced cells showed significantly reduced proliferative, migratory and invasive capacities, as well as significantly increased apoptosis. The shRNA-mediated GPC-3 silencing was accompanied by significant down-regulation of b-catenin mRNA (HepG2, 46.9+/-0.6%; MHCC-97H, 67.5+/-2.7%; Huh7, 56.3+/-8.4%) and significant up-regulation of GLI1 mRNA (HepG2, 49.2+/-28.6%; MHCC-97H, 54.6+/-24.4%; Huh7, 31.6+/-15.7%). At 72 h after transfection, the HepG2 cells showed significant down-regulation of VEGF protein (54.3+/-1.5%, t = 46.746, P less than 0.001). CONCLUSION: GPC-3 contributes to migration, invasion, angiogenesis, and apoptosis of hepatoma cells, possibly through its interactions with the Wnt/b-catenin and Hedgehog signaling pathways. GPC-3 may represent a useful target for gene silencing by molecular-based therapies to treat hepatocellular carcinoma.

[Effects of inhibited IGF-IR expression on proliferation and apoptosis of human hepatocellular carcinoma cell lines].

OBJECTIVE: To investigate the therapeutic value of inhibiting the expression of insulin-like growth factor-I receptor (IGF-IR) using picropodophyllin (PPP) by studying the effects on proliferative and metastatic potentials of human hepatocellular carcinoma (HCC) using an in vitro cultured cell system. METHODS: IGF-IR expression in human HCC cell lines (Bel-7404, Bel-7402, HepG2, and Huh-7) and human hepatocytes (L02) was assessed at baseline (pre-treatment) and after PPP treatment by western blotting. Changes in cell cycle were analyzed by flow cytometry and in cell viability by sulforhodamine B staining. Early apoptosis was detected by annexin-V/FITC and propidium iodide double-staining assay. Caspase-3/7 activity was suppressed by z-VAD-FMK and analyzed by homogeneous luminescence assay. Effects on cell motility were tested by wound-scratch test. Between-group differences were assessed by t-test or one-way analysis of variance. RESULTS: IGF-IR was markedly up-regulated in all HCC cell lines (vs. non-hepatoma hepatocytes). HCC cells with PPP-inhibited IGF-IR showed time-dependent decreases in cell motility and viability. After treatment with PPP for 24 hours, the proportion of HCC cells in G1 phase was 2.1% +/- 0.4%, in S phase was 11.0% +/- 0.7%, and in G2/M phase was 87.1% +/- 0.6%, and no healing was observed in the wound-scratch assay. The PPP treatment induced cell apoptosis, as evidenced by enhanced caspase-3/7 activity; the proportion of annexin-V+/PI- cells was significantly higher in the HepG2 cells than in the non-hepatoma hepatocytes (16.4% +/- 0.4% vs. 5.8% +/- 0.2%, t = 14.05, P less than 0.01). After z-VAD-FMK treatment, the apoptosis rate was significantly higher in the HepG2 cells than in the non-hepatoma hepatocytes (11.3% +/- 0.7% vs. 5.8% +/- 0.2%, t = 11.83, P less than 0.01). CONCLUSION: IGF-IR is associated with proliferation, cell motility, and apoptosis of HCC cells, and may be a promising molecular target for HCC.

[Abnormal expression of insulin-like growth factor-II and intervening of its mRNA transcription in the promotion of HepG2 cell apoptosis].

OBJECTIVE: To explore the expression and pathological features of insulin-like growth factor-II (IGF-II) in tissues and sera of hepatocellular carcinoma (HCC) patients and the siRNA-mediated inhibition of IGF-II mRNA transcription in human HepG2 cells. METHODS: From December 2009 to August 2010, the self-control HCC, paracancerous and distal cancerous tissues were collected to analyze the expression of IGF-II. The serum levels of IGF-II expression were detected for pathological features. IGF-II expression in HepG2 cells was intervened by siRNA. IGF-II mRNA or IGF-II level and analyzed by reverse transcription-polymerase chain reaction (RT-PCR), real-time PCR or enzyme-linked immunosorbent assay (ELISA). And the ratio of cell apoptosis was analyzed by EdU/Hoechst33342. RESULTS: The levels of IGF-II expression in HCC tissues at mRNA (100%, 30/30) or protein (83.3%, 25/30) were significantly higher (P < 0.01) than those in para-cancerous (46.7%, 53.3%) or distal cancerous tissues (0, 0). The serum level of IGF-II was significantly higher in HCC patients (3.74 ± 0.67) ng/L than that in cases with benign liver diseases (1.93 ± 0.17) ng/L and controls (1.14 ± 0.14) ng/L (P < 0.001). The expression of IGF-II in the HCC group was associated with HBV infection (t = 5.390, P < 0.001). After siRNA transfection, the expression of IGF-II decreased significantly in HepG2 cells at mRNA or protein levels. The down-regulated expression of IGF-II was dependent on the dose and time of IGF-II siRNA. And the apoptotic index of HepG2 cells and the sensitivity to adriamycin both increased. CONCLUSION: The expression of IGF-II is closely associated with the progression of HCC. And the intervening of its transcription may promote apoptosis and sensitize to adriamycin.

[Correlation between epigenetic alterations in the insulin growth factor-II gene and hepatocellular carcinoma].

To investigate whether epigenetic alterations in the insulin-like growth factor-II (IGF-II) gene that cause differential transcription or expression are correlated with onset and severity of hepatocellular carcinoma (HCC). Patient-matched specimens of HCC, paracancerous, and non-cancerous tissues were collected from 40 primary liver cancer patients. Epigenetic alterations in the promoter (P3) sequence of the IGF-II gene were analyzed by methylation-specific PCR (MSP) and IGF-II transcription was measured by RT-PCR. IGF-II protein expression and clinicopathological features were assessed by immunohistochemistry and microscopic observation. The rate of IGF-II P3 methylation was significantly lower in HCC tissues (0%) than in paracancerous tissues (vs. 47.5%; x2 = 24.918, P less than 0.001) and non-cancerous tissues (vs. 100%; x2 = 80.000, P less than 0.001). IGF-II mRNA expression was significantly higher in HCC tissues (100%) than in paracancerous tissues (vs. 52.5%; x2 = 24.918, P less than 0.001) and non-cancerous tissues (vs. 0%; x2 = 80.000, P less than 0.001). IGF-II protein expression was significantly higher in HCC tissues (82.5%) than in paracancerous tissues (vs. 45.0%; x2 = 12.170, P less than 0.001) and non-cancerous tissues (vs. 0%; x2 = 56.170, P less than 0.001). IGF-II overexpression in HCC was significantly associated with degree of differentiation, extent of infiltrated serosa, size of tumor, and HBV-positive infection status. Epigenetic alterations in the IGF-II gene regulate its transcription and expression and are closely associated with HCC development and progression.

[Expression features of glypican-3 and its diagnostic and differential values in hepatocellular carcinoma].

OBJECTIVE: To investigate the expression features of glypican-3 (GPC-3) and its diagnostic and differential values in hepatocellular carcinoma (HCC). METHODS: Rat hepatoma models were made and the dynamic expression features of GPC-3 protein and its gene were investigated by Western blotting and RT-PCR respectively. Liver specimens from 36 HCC patients were collected by self-control method and the expression and clinicopathological features of GPC-3 were analyzed by immunohistochemistry. Serum GPC-3 levels were quantitatively detected by ELISA and its efficiency for HCC diagnosis was evaluated in patients with liver diseases. RESULTS: The incidence of GPC-3 was 0% in control, 83.3% in degeneration, 100% in precancerosis and 100% in canceration during dynamic formation of rat hepatoma, respectively. The positive GPC-3 was brown granule- like staining localized in membrane and cytoplasm in human HCC. CONCLUSIONS: The GPC-3 positive rates were 80.6% in HCC, 41.7% in surrounding tissues and none in distal tissues (P < 0.01), respectively. No positive relationship presented between GPC-3 and differentiation grade or the number of tumor except of tumor size (Z = 2.941, P < 0.01). The incidence of serum GPC-3 was 52.8% in HCC patients except of one patient with cirrhosis. No significant differences were found between GPC-3 and sex, age, AFP, tumor number, Child classification or extrahepatic metastasis except of tumor size (χ² = 6.318, P < 0.05) and HBV infection (χ² = 23.362, P < 0.01). Combined detection of GPC-3 and AFP could rise up diagnosis of HCC. GPC-3 expression closely associated with HCC and might be useful for early diagnosis of HCC.

[Inhibitory effect of miRNA silencing hypoxia-inducible factor alpha subunit gene on the proliferation of HepG2 cells].

OBJECTIVE: To investigate the effect of miRNA silencing HIF-1α gene on the proliferation of HepG2 cells. METHODS: The eukaryotic expression plasmids of HIF-1α miRNA and report gene containing hypoxia-reponse element were constructed and transfected into HepG2 cells. The expressions of HIF-1α gene and protein were determined by real time-PCR and Western blotting. The expressions of HIF-1α, vascular endothelial growth factor (VEGF) and angiopoietin-2 (Ang-2) were quantitatively detected by ELISA. The alterations of cell cycles and apoptosis rate were quantitatively measured by flow cytometry and Annexin V-FITC/PI double dyeing assay. RESULTS: 72 h after transfection the down regulations of HIF-1α mRNA and protein were 87% and 56% respectively, and the decrease of target gene was 46% in the report gene, 54% in VEGF and 36% in Ang-2, respectively. The apoptotic ratio of HepG2 cells was 22.46+/-0.61% (P < 0.01). The cell cycle changed greatly at the ratio of G1 (61.49+/-1.12%) and S (22.40+/-0.58%, P < 0.01). After being combined with doxorubicin, the apoptotic ratio increased to 36.99+/-0.88% and the ratios of G1 and S phases were upregulated to 65.68+/-0.91% and 19.47+/-1.34% respectively. CONCLUSIONS: HIF-1α miRNA or / and doxorubicin can regulate the growth cycles of HepG2 cells, promote the cell apoptosis and inhibit the cell proliferation.

[Expression characteristics of hypoxia inducible factor-1a and its clinical values in hepatocellular carcinoma].

OBJECTIVE: To investigate the dynamic expression of hypoxia inducible factor-1alpha (HIF-1alpha) and its clinical values in hepatocellular carcinoma (HCC). METHODS: The dynamic changes of liver pathology, HIF-1alpha transcription and expression were observed through the hepatoma model. The self-control specimens from 35 human HCC patients were collected and the expression, cellular distribution, and clinicopathological features of HIF-1alpha and its gene was analyzed by immunohistochemistry, western blotting and nested- PCR, respectively. RESULTS: Both levels of hepatic HIF-1alpha and HIF-1alpha mRNA expression increased during the HCC development course. The incidence of HIF-1alpha and the ratio of HIF-1alpha to beta-actin was 0% and 0.16+/-0.02 in the control rats, 77.8% and 0.29+/-0.04 in the denatured rats, 88.9% and 0.52+/-0.03 in the precancerous rats, and 100% and 0.84+/-0.02 in the cancerous rats respectively, with significant difference between the control group and any of the experimental groups (P = 0.000). The positive HIF-1alpha was brown and granule-like and mainly presented in cytoplasm and few in nucleus. The incidence of HIF-1alpha was 80% (28/35) in HCC and 100% (35/35) in its surrounding tissues. The clinical pathological features indicated HIF-1alpha expression associated with tumor size and differentiation degree the of HCC. No correlation was found between HIF-1alpha and tumor numbers or positive-HBsAg. CONCLUSIONS: HIF-1alpha expression is associated with occurrence and development of HCC, and is perhaps a target molecule for HCC therapy.

Delayed hepatocarcinogenesis through antiangiogenic intervention in the nuclear factor-kappa B activation pathway in rats.

BACKGROUND: The active form of nuclear factor-kappa B (NF-kappaB) is involved in the initiation, generation, and development of hepatocellular carcinoma (HCC), and is up-regulated in inflammation-associated malignancies. We investigated the dynamic expression of NF-kappaB and its influences on the occurrence of HCC through antiangiogenic (thalidomide) intervention in NF-kappaB activation. METHODS: Hepatoma models were induced with 2-fluorenylacetamide (2-FAA, 0.05%) in male Sprague-Dawley rats, and thalidomide (100 mg/kg body weight) was administered intragastrically to intervene in NF-kappaB activation. The pathological changes in the liver of sacrificed rats were assessed after hematoxylin and eosin staining. NF-kappaB mRNA was amplified by RT-nested PCR. The alterations of NF-kappaB and vascular endothelial growth factor (VEGF) expression were analyzed by enzyme-linked immunosorbent assay, immunohistochemistry, and Western blotting. RESULTS: Rat hepatocytes showed denatured, precancerous, and cancerous stages in hepatocarcinogenesis, with an increasing tendency of hepatic NF-kappaB, NF-kappaB mRNA, and VEGF expression, and their values in the HCC group were higher than those in controls (P<0.001). In the thalidomide-treated group, the morphologic changes generated only punctiform denaturation and necrosis at the early or middle stages, and nodular hyperplasia or a little atypical hyperplasia at the final stages, with the expression of NF-kappaB (X2=9.93, P<0.001) and VEGF (X2=8.024, P<0.001) lower than that in the 2-FAA group. CONCLUSION: NF-kappaB is overexpressed in hepatocarcinogenesis and antiangiogenic treatment down-regulates the expression of NF-kappaB and VEGF, and delays the occurrence of HCC.

[Dynamic expression and quantitative analysis of hepatic nuclear factor-kappa B and its gene during the development of hepatocellular carcinoma].

OBJECTIVE: To investigate the kinetic expression and alteration of nuclear transcription factor-kappa B (NF-kappaB) and its gene in hepatocellular carcinoma (HCC) development. METHODS: A hepatoma model was established with N-(2-fluorenyl) acetamide (2-FAA) using male SD rats. Morphological changes and dynamic alterations of NF-kappaB and NF-kappaB mRNA of the rat livers at different stages of HCC development were observed by pathological examinations. The liver specimens from HCC patients were collected by self-control method. The expression of NF-kappaB was quantitatively analyzed by ELISA. RESULTS: Hepatocytes showed vacuole-like denaturation, atypical hyperplasia, and transformation into highly differentiated cancerous hepatocytes with increasing tendencies of liver NF-kappaB and NF-kappaB mRNA expressions. The NF-kappaB positive material was granule-like and stained brown, with dot-nest-like staining localized in the nuclei and cytoplasm of HCC cells, but only in the cytoplasm of the cells of park cancer tissues. Its expression in HCC cells was stronger than that in their surrounding tissues (chi2 = 13.1, P less than 0.01). No positive relationship was found between NF-kappaB expression and histological grades, the number of tumors, or size of the tumors. CONCLUSION: The expression of NF-kappaB and its gene are associated with the development of HCC. To inhibit the expression may be useful to HCC therapy.

Clinical impact of plasma TGF-beta1 and circulating TGF-beta1 mRNA in diagnosis of hepatocellular carcinoma.

BACKGROUND: Transforming growth factor-beta (TGF-beta) plays an important role in the regulation of cell growth and differentiation, angiogenesis, extracellular matrix formation, immunosuppression and cancer development. In this study, we investigated the levels of TGF-beta1 and TGF-beta1 mRNA expression, their relationship with HBV replication, and their diagnostic value for hepatocellular carcinoma (HCC). METHODS: Total RNAs were extracted from HCC samples and matched non-tumor tissues, and from peripheral blood mononuclear cells in HCC patients. TGF-beta1 mRNA was amplified by RT-PCR and confirmed by DNA sequencing. The distribution of TGF-beta1 expression was assessed by immunohistochemistry. The clinical characteristics were analyzed between TGF-beta1 and HBV replication. The diagnostic value of circulating TGF-beta1 and TGF-beta1 mRNA levels were investigated in HCC patients. RESULTS: The incidence of hepatic TGF-beta1 expression was 83.3% in HCC samples, 43.3% in the surrounding tissues, 94.7% in the HBV DNA-positive group, and 63.6% in the HBV DNA-negative group. Liver TGF-beta1 expression was associated with the degree of HCC differentiation and the status of HBV replication, but not with the size or number of tumors. Circulating TGF-beta1 level and incidence of TGF-beta1 mRNA were significantly higher in the HCC group than in any group of patients with benign liver disease, with a higher sensitivity of 89.5% and a specificity of 94.0% for HCC diagnosis when circulating TGF-beta1 levels were >1.2 microg/L. No significant correlation was found between TGF-beta1 expression and AFP level or tumor size. Combining TGF-beta1 level and serum AFP raised the detection rate to 97.4%. CONCLUSIONS: Abnormal expression of hepatic TGF-beta1 is associated with the degree of HCC differentiation and HBV replication. Both circulating TGF-beta1 and TGF-beta1 mRNA can be used as sensitive biomarkers for the diagnosis and prognosis of HBV-induced HCC.

[An evaluation of transforming growth factor-beta 1 in diagnosing hepatocellular carcinoma and metastasis].

OBJECTIVE: To investigate the dynamic expressions of TGF-beta 1 and TGF-beta 1 mRNA at different stages of hepatocellular carcinoma (HCC) development and their use in clinical diagnosis. METHODS: Hepatoma models were developed with 2-FAA using male Sprague-Dawley (SD) rats. Morphological changes of the rat liver histological preparations (H and E stained) were studied. The fragment of TGF-beta 1 gene obtained was amplified by nested RT-PCR. Dynamic change of TGF-beta 1 level was quantitatively analyzed by ELISA. The distribution of TGF-beta 1 in the cells and its gene expression were detected in human HCC tissues. RESULTS: The progressive increases of hepatic TGF-beta 1 and TGF-beta 1 mRNA were observed in rat hepatocytes which progressed from granular degeneration, atypical hyperplasia and finally to HCC development induced by 2-FAA. The expression levels in HCC tissues were significantly higher than those in the normal and degenerative ones. TGF-beta 1 was shown in rat hepatocytes by immunohistochemistry. Plasma TGF-beta 1 was detected in 89.5% of all the patients with HCC, but it was detected in 93.3% of them who had an AFP less than 400 microg/L. TGF-beta 1 mRNA showed a stronger expression in HCC tissues. TGF-beta 1 mRNA was found in peripheral blood mononuclear cells from all HCC patients with extrahepatic metastasis. CONCLUSION: TGF-beta 1 may participate in hepatocyte canceration. The overexpression of TGF-beta 1 and TGF-beta 1 mRNA could be useful markers for early diagnosis and predicting prognosis of HCC.

Specific molecular markers in hepatocellular carcinoma.

BACKGROUND: The carcinogenesis of hepatocellular carcinoma (HCC) is a multi-factorial, multistep and complex process. Its prognosis is poor, and early diagnosis and monitoring metastasis of HCC is of the utmost importance. Circulating diagnostic and prognostic biomarkers could be used in proper postoperative treatment of patients at an early stage of HCC development. This review summarizes recent studies of the specific biomarkers in diagnosis and monitoring metastasis or postoperative recurrence of HCC. DATA SOURCES: An English-language literature search was conducted using MEDLINE (June 1998 to September 2006) on researches of some valuable specific biomarkers in diagnosis and monitoring metastasis or postoperative recurrence of HCC. RESULTS: Hepatoma tissues can synthesize various tumor-related proteins, polypeptides, and isoenzymes, such as alpha-fetoprotein (AFP), hepatoma-specific gamma-glutamyl transpeptidase (HS-GGT), etc, and then secrete into blood. The valuable early diagnostic and prognostic biomarkers could predict the development and metastases of HCC. Recent researches have confirmed that circulating hepatoma-specific AFP subfraction, transforming growth factor (TGF)-beta1, HS-GGT, and free insulin-like growth factor (IGF)-II may be more specific markers than total AFP level for early diagnosis for HCC. The circulating genetic markers such as AFP-mRNA, TGF-beta1-mRNA, IGF-II-mRNA, etc from peripheral blood mononuclear cells of HCC patients have been most extensively used in monitoring distal metastasis or postoperative recurrence of HCC. CONCLUSIONS: Hepatoma tissues synthesize and secrete valuable molecular markers into blood. The analyses of circulating hepatoma-specific biomarkers are useful to early diagnosis of HCC or monitoring metastasis or postoperative recurrence of HCC.

Expression and alteration of insulin-like growth factor II-messenger RNA in hepatoma tissues and peripheral blood of patients with hepatocellular carcinoma.

AIM: To investigate the clinical values of serum free insulin-like growth factor II (IGF-II) levels and IGF-II mRNA in hepatocellular carcinoma (HCC) tissues and peripheral blood for diagnosis of HCC and monitoring of extrahepatic metastasis. METHODS: Total RNAs were extracted from HCC tissues or peripheral blood mononuclear cells from patients with HCC, liver diseases devoid of cancer, non-hepatic tumors, and healthy controls, respectively. IGF-II cDNAs were synthesized through random primers and reverse-transcriptase, amplified by polymerase chain reaction (PCR), and confirmed by DNA sequencing analysis. Serum free IGF-II levels in patients with different liver diseases were analyzed by an enzyme-linked immunosorbent assay. RESULTS: The amplified fragments of IGF-II mRNA by RT-PCR were identical to originally designed ones with a size of 170 bp and confirmed by sequencing analysis. The dilution experiments revealed that the lowest sensitivity of our system was 2 ng/L of total RNA. The positive frequencies of IGF-II mRNA were 100% in HCC tissues, 53.3% in para-cancerous tissues, and 0% in non-cancerous tissues, respectively. The serum free IGF-II levels were significantly higher in HCC than those in chronic hepatitis or liver cirrhosis. The positive frequency of circulating IGF-II mRNA was 34.2% in HCC, no amplified fragment was found in other liver diseases, extrahepatic tumors, and normal controls, respectively. The circulating IGF-II mRNA correlated with the stage of HCC, and its positive rate was 100% in HCC with extrahepatic metastasis and 35.5% in HCC with AFP-negative. No significant correlation was found between tumor sizes and circulating IGF-II mRNA fragment. CONCLUSION: The abnormal expressions of free IGF-II and IGF-II mRNA are useful tumor markers for HCC diagnosis, differentiation of extrahepatic metastasis and monitoring postoperative recurrence.