Combined serum hepatoma-specific alpha-fetoprotein and circulating alpha-fetoprotein-mRNA in diagnosis of hepatocellular carcinoma

BACKGROUND: Hepatocellular carcinoma (HCC) is one of the most common malignant tumors worldwide, its prognosis is poor, and early detection is of utmost importance. Although alpha-fetoprotein (AFP) is a useful marker for detecting and monitoring HCC development, the false-negative or false-positive rates with AFP alone may be as high as 30%-40% for patients with small HCCs. To enhance the specificity and accuracy of AFP measurements for HCC, we analyzed AFP expression states in livers, detected the hepatoma-specific AFP (HS-AFP) fraction and AFP-mRNA from peripheral blood mononuclear cells, and explored their clinical implications for HCC diagnosis. METHODS: AFP expression and hepatocyte distributions in liver specimens were investigated by an immunohistoche- mical assay. Total RNAs were extracted from circulating blood, synthesized to cDNA through random primers and reverse transcriptase, and fragments of the AFP gene were amplified by a nested-PCR assay. The HS-AFP fraction was separated by lectin-affinity chromatography and its level was detected by radioimmunoassay. RESULTS: The incidence of AFP was 73.3% in HCC tissues and its expression in HCCs with moderate or low differentiation was significantly stronger than that of HCCs with high differentiation (P<0.05). The incidence of AFP gene fragments was 100% in HCCs, and 60% in paracancerous tissues (P<0.01). In the HCC and liver cirrhosis groups, the incidence of HS-AFP was 91.7% and 18% (P<0.01), and of AFP-mRNA was 56.7% and 16% (P<0.01), respectively, and neither was found in controls.HS-AFP or AFP-mRNA was not significantly related to size or number of HCC, but to its differentiation, metastasis, and relapse (P<0.05). CONCLUSIONS: Different AFP expression is present in different parts of HCC tissues. HS-AFP and AFP-mRNA fragments improve sensitivity and specificity, and both are useful markers to diagnose HCC or monitor metastasis and relapse.

Quantitative analysis of hepatoma-specific α-fetoprotein(HS-AFP) by a new mini-column affinity chromatography and its clinical value in diagnosis of hepatocellular carcinoma

Objective： To establish a convenient and economic method to determine hepatoma-specific α-fetoprotein （HS- AFP） for diagnosis of hepatocellular carcinoma （HCC）. Methods： HS-AFP from serum of HCC patients was separated by a mini-column Lens culinaris agglutinin （LCA）-affinity chromatography. The levels of serum total AFP and separated HS-AFP were detected by radioimmunoassay （RIA）. Results： Circulating AFP was separated into three peaks （AFP-1, AFP-2, and AFP-3） by LCA-affinity chromatography. Dunng the elution course, the AFP-1 and AFP-2 could be eluted with TE buffer. HSAFP （AFP-3） from sera of HCC patients was eluted clearly on the LCA-sepharose gel mini-column with a solution containing α-methyI-D-mannoside. It was a part of total AFP and only found in sera of HCC patients. A ratio of more than 15% for HS-AFP to total AFP in serum was considered as a specific marker for HCC diagnosis with higher sensitivity （92.7%） and specificity （88.2%）. Conclusion： The new assay for circulating HS-AFP analysis is more sensitive, repeatable, and convenient. Its clinical application would be useful to early diagnosis of HCC.

Diagnostic and monitoring values of circulating AFPmRNA and HS-GGT for hepatocellular carcinoma

Objective: Early finding of hepatocellular carcinoma(HCC) and monitoring of its metastasis are of the utmost importance. The objectives of this study were to investigate the values of circulating hepatoma-specific gamma-glutamyl transferase(HS-GGT) fraction and α-fetoprotein mRNA(AFP-mRNA) from peripheral blood mononuclear cells(PBMCs) in diagnosis or monitoring metastasis of HCC. Methods: Total RNA was extracted from hepatomas or PBMCs of patients, synthesized to AFP-cDNA through random primers and reverse transcriptase, amplified by using a nested PCR assay, and confirmed by sequencing. Simultaneity, the HS-GGT activities were quantitatively determined in sera of patients. The comprehensive assessments of two markers were investigated in HCC patients. Results: The amplified fragments of AFP-mRNA were identical to original designed ones(159 bp) and confirmed by sequencing. The lowest sensitivity was 2 ng/L of total RNA. The incidences of AFP-mRNA and HS-GGT were 60.4%(113 of 187) and 84.5%(158 of 187) in the HCC group, and their significantly higher(P < 0.01) than that in any of other groups. The high frequencies of HS-GGT and AFP-mRNA were 78.2% and 56.4% in the HCC patients with AFP < 50 ng/mL. All positive of AFP-mRNA was found in HCC patients with extrahepatic metastasis. No significant correlation was found between tumor size and AFP-mRNA or HS-GGT. The total incidence of combined AFP-mRNA and HS-GGT detection was 93.6 % for HCC diagnosis. Conclusion: HS-GGT and AFP-mRNA are specific markers for HCC diagnosis or differentiation, especially the former for early finding and the later for monitoring metastasis of HCC.