Clusterin is a potential serum marker of hepatic carcinoma / 中华肝脏病杂志

<p><b>OBJECTIVE</b>To determine the differentially expressed serum proteins in patients with hepatoma carcinoma and identify a putative diagnostic marker.</p><p><b>METHOD</b>The isobaric tags for relative and absolute quantitation (iTRAQ) labeling method and LC-MALDI-TOF/TOF MS detection method were used to quantify serum proteins in hepatocellular carcinoma patients (n =20) and healthy individuals (n =20). Real-time reverse transcription-polymerase chain reaction was used to verify the differentially expressed proteins by analyzing the corresponding mRNA expression levels in the hepatic carcinoma and healthy hepatocyte samples, as well as in 30 pairs of patient-matched hepatic carcinoma and adjacent normal tissue samples. Western blot analysis was used to verify the protein expression in hepatic carcinoma cells.</p><p><b>RESULT</b>Fifty-one proteins were significantly differentially expressed between the hepatic carcinoma group and healthy controls. The iTRAQ protein profile showed that the serum level of clusterin was significantly lower in hepatoma carcinoma patients. The mRNA level of clusterin was 20-fold lower in hepatic carcinoma cells than in healthy hepatocytes, and was 2.38-fold lower in hepatoma tissues than that in adjacent normal tissues. The clusterin protein levels were significantly lower in hepatic carcinoma cells (8.06 vs normal hepatocytes: 27.81; P less than 0.01).</p><p><b>CONCLUSION</b>The serum expression of clusterin is significantly decreased in both serum and tissues of hepatic carcinoma patients. The relationship between hepatic carcinoma and clusterin should be evaluated in future studies.</p>

iTRAQ analysis of serum biomarkers of hepatocellular carcinoma based on mass spectrometry / 肿瘤

Objective: The technique of isobaric tags for relative and absolute quantitation (iTRAQ) was used to analyze the expression levels of serum biomarkers of hepatocellular carcinoma (HCC) based on mass spectrometry. Methods: The literature about HCC biomarkers identified by screening of differential protein expression combined with matrix-assisted laser desorption/ ionization time-of-flight mass spectrometry (MALDI-TOF-MS) published between January 2003 and August 2010 were selected by searching PubMed database. Screening for serum differential proteins was performed in 20 HCC patients and 20 healthy volunteers by using iTRAQ labeling and MALDI-TOF-MS. The reported data of HCC biomarkers were compared with the screening results of serum differential protein expression in HCC. Results: Twenty-two pieces of eligible literature were obtained by information retrieval, involving 262 HCC biomarkers. Fifty-one proteins were identified having differential expression by using screening of serum differential protein expression in HCC. In the 51 proteins, the expression level of 23 proteins was high, while the expression level of 28 proteins was low. Eight differential proteins which were identified by screening, were in accordance with literature reports, and 6 differential proteins (alpha-1-antitrypsin, apolipoprotein E, ceruloplasmin, alpha fetoprotein, complement C3 and serum amyloid P-component) had the similar expression levels in accordance with literature reports. Conclusion: Six differential proteins identified in serum are the same as reported in the literatures, and these proteins may become potential HCC biomarkers. There is a need for further study to explore these differential proteins. Copyright© 2011 by Tumor.