Overexpression of squamous cell carcinoma antigen 1 is associated with the onset and progression of human hepatocellular carcinoma

Background and aims: Previous studies indicated Squamous Cell Carcinoma Antigen 1 (SCCA1) may be involved in tumorigenesis and progress of various human malignancies by inhibiting cell apoptosis and promoting cell proliferative activity. The aim of the study was to further investigate SCCA1 expression in different extent of liver diseases and evaluate the clinical significance and prognostic value in HCC.

Methods: Eighty nine patient-matched tumors and peritumoral surgical specimens and 56 liver biopsies specimens from 23 patients with chronic hepatitis B (CHB), 19 with dysplastic nodule (DN), and 14 with HCC were enrolled. An additional four normal liver (NL) samples were used as controls. SCCA1 expression in liver tissue was measured by immunochemistry. Another 28 HCC specimens and paired non-tumor tissues were used for SCCA1 detection by Western blot. The prognostic value of SCCA1 expression in HCC was evaluated by the Cox proportional hazards regression model analysis.

Results: Western blot analysis showed SCCA1 positive rate in HCC was higher than the matched adjacent noncancerous tissues (p <0.001). Immunohistochemistry revealed that SCCA1-positive rate increased gradually from NL, CHB, PNT to DN and HCC (p <0.05). Clinicopathological analysis showed that SCCA1 expression was positively associated with tumor differentiation (p = 0.043) and patients' Child-Pugh score (p = 0.021). The SCCA1-poistive group showed better overall survival than the negative group (p = 0.029). Importantly, SCCA1 expression was an independent prognostic factor for the overall survival of HCC patients (hazard ratio = 3.757, p <0.001).

Conclusion: SCCA1 expression pattern may relate to the progression of chronic liver diseases. Furthermore, our study supports a potential association of negative SCCA1 expression with poor outcome in HCC.