[Correlation of NY-ESO-1 gene and protein expression to metastasis and clinicopathologic features of hepatocellular carcinoma].

BACKGROUND & OBJECTIVE: NY-ESO-1 belongs to cancer-testis antigen family. It can inspire both cellular and humoral immune responses in tumor patients, and is regarded as the strongest tumor antigen. This study was to investigate the expression of NY-ESO-1 gene and its correlation with clinicopathologic features of hepatocellular carcinoma (HCC).

METHODS

NY-ESO-1 mRNA expression was detected by reverse transcription-polymerase chain reaction (RT-PCR) in 62 specimens of HCC and adjacent liver tissue. NY-ESO-1 protein expression and its distribution were detected by immunohistochemistry (IHC) in a tissue microarray contained 132 eligible cases of HCC.

RESULTS

Positive rate of NY-ESO-1 mRNA was 27.4% in HCC; it was higher in HCC with tumor embolus of portal vein than in HCC without tumor embolism (40.0% vs. 18.9%). Positive rate of NY-ESO-1 protein was 18.9% in HCC tissue microarray; it was significantly higher in HCC with metastasis than in HCC without metastasis (29.6% vs. 11.5%, P < 0.05). NY-ESO-1 protein mainly located in cytoplasm of HCC cells. Positive rates of NY-ESO-1 mRNA and protein were 28.3% and 19.1% respectively in HBsAg positive HCC, and were 29.5% and 20.7% respectively in HCC with alpha fetoprotein (AFP) of > 20 ng/ml. Both NY-ESO-1 mRNA and protein were not detected in adjacent normal liver tissue.

CONCLUSIONS

NY-ESO-1 gene specifically expresses in HCC, and may correlates with progress and metastasis of HCC. It may be a candidate target for antigen-specific immunotherapy for HCC with metastatic lesion. NY-ESO-1 expression has no correlation with HBsAg/AFP status of HCC.