Expression of SSX-1 and SSX-5 genes in the peripheral blood of patients with hepatocellular carcinoma

Abstract

Background: Liver cancer is the fifth most common cancer in men and the seventh in women. Hepatocellular carcinoma (HCC) is responsible for significant morbidity and mortality in patients with liver cirrhosis and accounts for 90% of primary liver cancer. Synovial sarcoma X chromosome (SSX) genes belong to cancer testis antigens (CTA) family; expressed only in germ cell tumors. There have been some studies about the SSX genes expression in the HCC. To the best of our knowledge no reports included these genes expression in the Egyptian patients with HCC.

Aim: This study aims to evaluate the SSX-1 and SSX-5 mRNA expression in tumor cells circulating in the peripheral blood (PB) of a cohort of Egyptian patients with HCC and to find out any possible associations between these genes expression and different clinical/laboratory parameters.

Subjects and methods: This study included 100 subjects; 52 HCC cases, 25 with post viral hepatitis liver cirrhosis and 23 apparently healthy controls. Expression of SSX-1 and SSX-5 mRNA in PB was tested by reverse transcription polymerase chain reaction (RT-PCR).

Results: SSX-1 and SSX-5 mRNA were expressed in 40.4% and 36.5% of the HCC patients, respectively. SSX-1 and/or SSX-5 were not detected in healthy controls or cirrhotic patients. Neither SSX-1 nor SSX-5 expression showed an association with Alfa-Fetoprotein (AFP) levels, tumor size, tumor differentiation, hepatitis B infection and Bilharziasis (P >0.05).

Conclusion: SSX-1 and SSX-5 mRNA are specifically expressed in tumor cells circulating in PB of HCC patients and thus could be used as easy access, simple method molecular markers for early diagnosis of HCC patients in Egypt.

Keywords: SSX-1; SSX-5; Gene expression; Peripheral blood; Hepatocellular carcinoma