ABSTRACT
OBJECTIVES: To detect serum antibody against SMP30 in HCC patients and to evaluate its potential associations with HCC patient's clinical parameter and expression levels in HCC tissues. DESIGN AND METHODS: Serum antibody to SMP30 was tested by ELISA method; SMP30 mRNA and protein expression in HCC patients were analyzed using the methods of in situ nucleic acid hybridization and immunohistochemistry, respectively. RESULTS: The highest relevance of SMP30 antibody was associated with HCC (32.4%). The positive rate of SMP30 antibody was not related to the age of patients, tumor size, metastasis and infections of HBV, but the positive rate for SMP30 antibody in the HCC sera with alpha-fetoprotein (AFP) negative was higher (43.6%) compared with that AFP positive (26.2%). Both SMP30 mRNA and protein expression levels were downregulated in HCC and upregulated in adjacent tissues. CONCLUSIONS: SMP30 may be useful for HCC serologic screening, especially for the patients with AFP negative.
Subject(s)
Antibodies/metabolism , Calcium-Binding Proteins/metabolism , Carcinoma, Hepatocellular/genetics , Carcinoma, Hepatocellular/immunology , Intracellular Signaling Peptides and Proteins/metabolism , Liver Neoplasms/genetics , Liver Neoplasms/immunology , Adolescent , Adult , Aged , Antibodies/immunology , Biomarkers, Tumor/genetics , Biomarkers, Tumor/immunology , Biomarkers, Tumor/metabolism , Calcium-Binding Proteins/genetics , Calcium-Binding Proteins/immunology , Carcinoma, Hepatocellular/metabolism , Carcinoma, Hepatocellular/pathology , Case-Control Studies , Down-Regulation , Enzyme-Linked Immunosorbent Assay , Female , Gene Expression , Humans , Immunohistochemistry , In Situ Hybridization , Intracellular Signaling Peptides and Proteins/genetics , Intracellular Signaling Peptides and Proteins/immunology , Liver Neoplasms/metabolism , Liver Neoplasms/pathology , Male , Middle Aged , RNA, Messenger/analysis , Up-Regulation , Young Adult , alpha-Fetoproteins/genetics , alpha-Fetoproteins/metabolismABSTRACT
BACKGROUND: Serological identification of antigens by recombinant expression cloning (SEREX) is a promising method used to analyze tumor-associated antigen (TAA). Nineteen primary HCC-associated antigens have been found from a HCC cDNA library using autogenous serum by the SEREX approach. We searched for HCC-associated antigens and applied them to HCC diagnosis. METHODS: Nine of 19 primaries HCC-associated antigens identified by SEREX method were tested their immune response again with distinct allogeneic sera. One of the screened HCC-associated antigens, HCC-22-5 was recombined and expressed and made the frequency analysis of its seropositivity in various patients using the methods of Western-blot and ELISA. RESULTS: SEREX analysis showed that 9 primary HCC-associated antigens had high-titered IgG antibody in the majority of HCC patients. Western-Blot method confirmed that 3/7 HCC patients had antibodies against HCC-22-5, which demonstrated that expressed HCC-22-5 antigen had the character of antigen. Sera samples from 341 patients and 80 normal individuals have been tested for autoantibodies against HCC-22-5 by ELISA method. The results found that 51/128 of HCC, 11/76 of chronic hepatitis, 11/22 of liver cirrhosis and 8/54 of nasopharynx cancer patients had antibodies against HCC-22-5. No antibody response to HCC-22-5 had been found in the sera of 7 lung cancers, 54 gastric-intestine patients and 80 normal individuals. The groups of HCC and liver cirrhosis had higher antibody positive rate than that of other groups (p<0.05). In the HCC sera with alpha-fetoprotein (AFP) negative, the positive rate of HCC-22-5 was as high as 78.9%. CONCLUSIONS: HCC-22-5 can be used for HCC serologic screening, especially for the patients with AFP negative.
