Dynamic Expression Of Glypican-3 During The Formation Of Hepatocellular Carcinoma And Its Clinical Significances

Objective The prognosis of hepatocellular carcinoma (HCC) is very poor. Both of early diagnosis (small-size HCC) and early treatment (operation) are of the utmost importance for prolonging survival. HCC could be diagnosed by HCC markers and imaging technologies. Although serumα-fetoprotein (AFP) is a useful tumor marker for the detection and monitoring of HCC development with the false-negative rate or the false-positive rate with AFP level alone. Other markers such as AFP-L3, AFP-mRNA, GGT-Ⅱ, PIVKAⅡand AFU are proposed as predictive markers of HCC, especially the patients with false-negative AFP level and diagnosis of small-size HCC. Glypican-3 (GPC-3) plays an important role in regulating cells growth and closely related with hepatocellular carcinoma. In the present study, the HCC model was constructed in rats, and the characteristics of hepatic GPC-3mRNA dynamic expression were firstly investigated at different stages of HCC formation, and secondly its clinical significances were analyzed in early diagnosis. The expressions of human hepatic GPC-3 in different tissues of HCC were also studied.Methods Rat hepatoma models were induced with 2-fluorenylacetamide (2-FAA) on male Sprague-Dawley (SD) rats. Morphological changes of rat livers were observed by pathological examinations (H&E staining). Total RNA were extracted, hepatic GPC-3 gene fragments were amplified by nested reverse transcriptive polymerase chain reaction (RT-PCR) for exploring expression features and early diagnostic values in hepato- cancerogenesis. Liver specimens from 36 HCC patients were collected by self-control method. The expression, cellular distribution, and pathological features of GPC-3 were analyzed by immunohistochemical technique.Results Histological examination confirmed the rat hepatocytes from granule-like degeneration to atypical hyperplasia and HCC development after induced with 2-FAA, and the progressing increasing of hepatic total RNA level. The incidences of GPC-3 gene amplified fragments were 100% in HCC, 100% in precancerous tissues, 83.3% in degeneration liver tissues, and none in normal controls, respectively. There were closely positive relationship was found between GPC-3mRNA and total RNA expression. The positive substances of GPC-3 was brown granule-like or dot-nest-like staining localized in membrane and cytoplasm in HCC, and only in cytoplasm in its surrounding tissues. No staining was found in the distant tissues. Its expression in HCC was well-distributed and stronger than in its surrounding tissues. The incidence of GPC-3 was 80.6% in HCC tissues, and 41.7% in its surrounding tissues, respectively. Significant difference was found between the two groups (χ2 =11.445, P = 0.001). No positive relationship presented between GPC-3 expression and histological differentiation grade , number of tumor,size of tumor , HBsAg positive status. Significant difference was found between HCC and surrounding tissues or distant tissues.Conclusions Hepatic GPC-3 may be associated closely with occurrence and development of HCC. Both of GPC-3 and GPC-3mRNA over expression could be useful molecular markers for early diagnosis of HCC.