ABSTRACT
OBJECTIVES: Osteopontin (OPN) is a secreted glycoprotein, frequently associated with various tumors. We investigated the usefulness of plasma OPN level as a biomarker for hepatocellular carcinoma (HCC). METHODS: We determined plasma levels of OPN, alpha-fetoprotein (AFP), and prothrombin induced by vitamin K absence II (PIVKA II) in a group of 62 HCC patients, in 60 patients with chronic liver diseases, and in 60 healthy control individuals using a standardized ELISA kit. To determine the source of elevated plasma level of OPN, immunohistochemical analysis of 285 HCC samples on tissue microarray was performed. RESULTS: Plasma OPN levels in the HCC patients (median 954 ng/mL, range 168-5,742) were significantly higher (p-value < 0.001) than those patients with chronic liver diseases (381 ng/mL, 29-1,688) or of a healthy control group (155 ng/mL, 10-766). Within the HCC patient group, plasma OPN level increased significantly with advancing degree of Child-Pugh class and of tumor stage. Diagnostic sensitivity and specificity of OPN for HCC was 87% and 82%, respectively (cut-off value: 617.6 ng/mL). OPN had a greater area under curve value (0.898) than AFP (0.745) or PIVKA II (0.578), suggesting superior diagnostic accuracy of OPN. Immunohistochemistry of 285 samples of HCC showed that OPN was expressed in 92 of 285 tumors (32.3%). OPN expression was found in the malignant hepatocytes and cancer-infiltrating macrophages, not in the noncancerous hepatocytes or Kupffer cells. CONCLUSIONS: These data propose elevated plasma OPN levels as a potential biomarker for HCC.
Subject(s)
Biomarkers, Tumor/blood , Carcinoma, Hepatocellular/blood , Liver Neoplasms/blood , Phosphoproteins/blood , Sialoglycoproteins/blood , Biomarkers/blood , Carcinoma, Hepatocellular/pathology , Carcinoma, Hepatocellular/surgery , Diagnosis, Differential , Enzyme-Linked Immunosorbent Assay , Female , Follow-Up Studies , Hepatectomy , Humans , Immunohistochemistry , Liver Neoplasms/pathology , Liver Neoplasms/surgery , Male , Middle Aged , Neoplasm Staging , Osteopontin , Prognosis , Protein Precursors/blood , Prothrombin , ROC Curve , Severity of Illness Index , alpha-Fetoproteins/metabolismABSTRACT
IL-1beta increased the production of proenzyme of MMP-9 (pro-MMP-9) in a time- and dose-dependent manner in murine macrophage RAW 264.7 cells. However, the production of MMP-2 was not significantly changed by IL-1beta treatment. The intracellular H(2)O(2) content, as determined with H(2)O(2)-sensitive probe 2('),7(')-dichlorodihydrofluorescein, also increased after IL-1beta treatment (5ng/ml). In addition, exogenous H(2)O(2) (50 microM) was found to increase the production of pro-MMP-9. Transient transfection study using a MMP-9 promoter-reporter construct showed that IL-1beta enhanced the MMP-9 promoter activity. Electrophoretic mobility shift assay and site-directed mutagenesis study on the consensus binding site for NF-kappaB revealed that the activation of NF-kappaB is required for the IL-1beta-induced activation of MMP-9 promoter. N-acetylcysteine, an antioxidant, could abrogate the production of pro-MMP-9, H(2)O(2) generation, and activation of NF-kappaB and MMP-9 promoter. These results suggest that IL-1beta upregulates the MMP-9 expression via production of reactive oxygen species and activation of NF-kappaB in RAW 264.7 cells.
