Jun-Ling Yang

Oncofetal antigen glypican-3 as a promising early diagnostic marker for hepatocellular carcinoma

BACKGROUND Hepatocellular carcinoma (HCC) is characterized by a multi-cause, multi-stage and multi-focus process of tumor progression. Its prognosis is poor and early diagnosis is of utmost importance. This study was undertaken to investigate the dynamic expression of oncofetal antigen glypican-3 (GPC-3) and GPC-3 mRNA in hepatocarcinogenesis and to explore their early diagnostic value for HCC. METHODS A hepatoma model was induced in male Sprague-Dawley rats with 0.05% 2-fluorenylacetamide and confirmed by hematoxylin and eosin staining and gamma-glutamyltransferase (GGT) expression. Total RNA was purified and transcribed into cDNA by reverse transcription. Fragments of the GPC-3 gene were amplified by nested RT-PCR, and confirmed by sequencing. GPC-3 was analyzed by immunohistochemistry, Western blotting or ELISA. RESULTS Positive GPC-3 expression showed as brown granule-like staining localized in the cytoplasm. Histological examination of hepatocytes revealed three morphological stages of granule-like degeneration, atypical hyperplasia (precancerous), and cancer formation, with a progressive increase of liver total RNA and GGT expression. The incidence of liver GPC-3 mRNA and GPC-3, and serum GPC-3 was 100%, 100% and 77.8% in the HCC group, 100%, 100%, and 66.7% in the precancerous group, 83.3%, 83.3%, and 38.9% in the degeneration group, and no expression in the liver or blood of the control group, respectively. There was a positive correlation between liver GPC-3 mRNA and total RNA level (r=0.475, P<0.05) or liver GPC-3 (r=1.0, P<0.001) or serum GPC-3 (r=0.994, P<0.001). CONCLUSION Abnormal oncofetal antigen GPC-3 and GPC-3 mRNA expression in hepatocarcinogenesis may be promising molecular markers for early diagnosis of HCC.

Values of circulating GPC-3 mRNA and alpha-fetoprotein in detecting patients with hepatocellular carcinoma.

BACKGROUND The prognosis of hepatocellular carcinoma (HCC) is poor and its early diagnosis is of the utmost importance. This study aimed to investigate the values of glypican-3 (GPC-3) expression in the liver and sera and its gene transcription for diagnosis and monitoring of metastasis of HCC. METHODS Liver GPC-3 was analyzed in HCC tissues from 36 patients by immunohistochemistry and Western blotting. GPC-3 mRNA from circulating peripheral blood mononuclear cells from 123 HCC patients or 246 patients with other diseases or 36 HCC tissues was amplified by RT-PCR, quantitative real-time PCR, and confirmed by DNA sequencing. Circulating GPC-3 level was detected by ELISA. RESULTS The increasing expression of GPC-3 was observed from non-cancerous to cancerous tissues, with brown granule-like staining localized in tumor parts of atypical hyperplasia and HCC formation. The positive rate of GPC-3 was 80.6% in HCC, 41.7% in their paracancerous tissues, and none in distal cancerous tissues (P<0.001), with no significant difference in differentiation grade and tumor number except for size (Z=2.941, P=0.003). Serum GPC-3 was detected only in HCC (52.8%) and significant difference was found between GPC-3 and tumor size (X2=6.318, P=0.012) or HBV infection (X2=23.362, P<0.001). Circulating GPC-3 mRNA was detected in 70.7% of HCC tissues, with relation to TNM stage, periportal cancerous embolus, and extra-hepatic metastasis (P<0.001). The combination of circulating GPC-3, GPC-3 mRNA and alpha-fetoprotein is of complementary value for HCC diagnosis (94.3%). CONCLUSION Both GPC-3 overexpression and GPC-3 mRNA abnormality could be used as markers for the diagnosis of HCC and monitoring its metastasis.

Reversal of multidrug resistance of hepatocellular carcinoma cells by metformin through inhibiting NF-κB gene transcription.

AIM To interfere with the activation of nuclear factor-κB (NF-κB) with metformin and explore its effect in reversing multidrug resistance (MDR) of hepatocellular carcinoma (HCC) cells. METHODS Expression of P-glycoprotein (P-gp) and NF-κB in human HepG2 or HepG2/adriamycin (ADM) cells treated with pCMV-NF-κB-small interference RNA (siRNA) with or without metformin, was analyzed by Western blot or fluorescence quantitative PCR. Cell viability was tested by CCK-8 assay. Cell cycle and apoptosis were measured by flow cytometry and Annexin-V-PE/7-AnnexinV apoptosis detection double staining assay, respectively. RESULTS P-gp overexpression in HepG2 and HepG2/ADM cells was closely related to mdr1 mRNA (3.310 ± 0.154) and NF-κB mRNA (2.580 ± 0.040) expression. NF-κB gene transcription was inhibited by specific siRNA with significant down-regulation of P-gp and enhanced HCC cell chemosensitivity to doxorubicin. After pretreatment with metformin, HepG2/ADM cells were sensitized to doxorubicin and P-gp was decreased through the NF-κB signaling pathway. The synergistic effect of metformin and NF-κB siRNA were found in HepG2/ADM cells with regard to proliferation inhibition, cell cycle arrest and inducing cell apoptosis. CONCLUSION Metformin via silencing NF-κB signaling could effectively reverse MDR of HCC cells by down-regulating MDR1/P-gp expression.

Chemosensitization of HepG2 cells by suppression of NF-κB/p65 gene transcription with specific-siRNA

AIM To investigate small interfering RNA (siRNA)-mediated inhibition of nuclear factor-kappa B (NF-κB) activation and multidrug-resistant (MDR) phenotype formation in human HepG2 cells. METHODS Total RNA was extracted from human HepG2 or LO2 cells. NF-κB/p65 mRNA was amplified by nested reverse transcription polymerase chain reaction and confirmed by sequencing. NF-κB/p65 was analyzed by immunohistochemistry. Specific-siRNA was transfected to HepG2 cells to knock down NF-κB/p65 expression. The effects on cell proliferation, survival, and apoptosis were assessed, and the level of NF-κB/p65 or P-glycoprotein (P-gp) was quantitatively analyzed by enzyme-linked immunosorbent assay. RESULTS HepG2 cells express NF-κB/p65 and express relatively less phosphorylated p65 (P-p65) and little P-gp. After treatment of HepG2 cells with different doses of doxorubicin, the expression of NF-κB/p65, P-p65, and especially P-gp were dose-dependently upregulated. After HepG2 cells were transfected with NF-κB/p65 siRNA (100 nmol/L), the expression of NF-κB/p65, P-p65, and P-gp were downregulated significantly and dose-dependently. The viability of HepG2 cells was decreased to 23% in the combination NF-κB/p65 siRNA (100 nmol/L) and doxorubicin (0.5 μmol/L) group and 47% in the doxorubicin (0.5 μmol/L) group (t = 7.043, P < 0.001). CONCLUSION Knockdown of NF-κB/p65 with siRNA is an effective strategy for inhibiting HepG2 cell growth by downregulating P-gp expression associated chemosensitization and apoptosis induction.

Abnormal Expression of Golgi Protein 73 in Clinical Values and Their Role in HBV-Related Hepatocellular Carcinoma Diagnosis and Prognosis.

Background: The up-regulation of hepatic Golgi protein 73 (GP73) is associated with the progression of hepatocellular carcinoma (HCC). However, the exact mechanism and clinical values of its diagnosis and prognosis still need to be clarified. Objectives: To investigate the clinical values of abnormal liver or circulating GP73 expression and their effect on HCC diagnosis and prognosis. Materials and Methods: The expression of GP73 was investigated in 88 cancerous and self-control non-cancerous tissues using tissue microarrays with immunohisto- chemistry and was confirmed by Western blotting. Circulating GP73 levels were detected in the sera of 281 patients with liver diseases using enzyme-linked immunosorbent assay. Results: The levels of circulating GP73 expression in the HCC group were higher than those in any group of benign liver diseases or controls. No significant difference was found between GP73 expression and patients’ sex or age, tumor size, or AFP level except for those with hepatitis B virus (HBV) infection or distal metastasis (P < 0.05). The area under the receiver operating characteristic curve, sensitivity, and specificity for HCC diagnosis were 0.881, 78.34%, and 77.59% for GP73 levels over 70 μg/L or 0.754, 71.97%, and 84.48% for alpha-fetoprotein levels over 50 μg/L, respectively. The total incidence of GP73 plus alpha-fetoprotein was up to 87.26% for HCC. A positive GP73 result with brown particles was mainly located in the cytosol, with a few in the nucleus and none in the cell membrane, with abnormal expression in HCC tissues (480.7 ± 148.7) that was significantly higher (t = 10.730, P < 0.001) than those in their non-cancerous tissues (208.0 ± 66.1). The high GP73 expression in HCC was related to lymph node metastasis (χ2 = 6.940, P = 0.008), gross classification (χ2 = 6.311, P = 0.012), HBV (χ2 = 4.803, P = 0.028), tumor node metastasis staging (χ2 = 4.887, P = 0.027), and five-year survival (χ2 = 5.206, P = 0.023). Conclusions: Abnormality of hepatic or circulating GP73 expression should be regarded as an emerging biomarker for HCC diagnosis and prognosis.

Oncogenic secretory clusterin in hepatocellular carcinoma: Expression at early staging and emerging molecular target.

Secretory clusterin (sCLU) is associated with hepatocellular carcinoma (HCC) progression by contributing to angiogenesis, chemoresistance, cell survival, and metastasis. However, the sCLU expression at early stage of HCC progression remains to be clarified. In this study, the alteration of sCLU oncogenicity was firstly evaluated in HCC- and their para-cancerous- tissues. The incidence of sCLU expression in HCC was significantly higher than that in their non-tumorous tissues at message RNA (mRNA) or protein level, gradually increasing with tumor-node-metastasis (TNM) staging. Abnormal sCLU expression was associated with the poor differentiation, TNM stage, and considered as an independent prognostic factor for HCC patients. Furthermore, silencing sCLU gene transcription inhibited the colony formation and proliferation of HCC cells, with decreasing phosphorylation level of AKT and GSK-3β in HCCLM3 cells in vitro and significantly suppressed the HCC xenograft growth in vivo, suggesting that sCLU with oncogenicity should be not only an early indicator but also novel potential molecular-targeted therapy for HCC.Secretory clusterin (sCLU) is associated with hepatocellular carcinoma (HCC) progression by contributing to angiogenesis, chemoresistance, cell survival, and metastasis. However, the sCLU expression at early stage of HCC progression remains to be clarified. In this study, the alteration of sCLU oncogenicity was firstly evaluated in HCC- and their para-cancerous- tissues. The incidence of sCLU expression in HCC was significantly higher than that in their non-tumorous tissues at message RNA (mRNA) or protein level, gradually increasing with tumor-node-metastasis (TNM) staging. Abnormal sCLU expression was associated with the poor differentiation, TNM stage, and considered as an independent prognostic factor for HCC patients. Furthermore, silencing sCLU gene transcription inhibited the colony formation and proliferation of HCC cells, with decreasing phosphorylation level of AKT and GSK-3β in HCCLM3 cells in vitro and significantly suppressed the HCC xenograft growth in vivo, suggesting that sCLU with oncogenicity should be not only an early indicator but also novel potential molecular-targeted therapy for HCC.