Surface expression of squamous cell carcinoma antigen (SCCA) can be increased by the preS1(21-47) sequence of hepatitis B virus.
A variant of the serpin squamous cell carcinoma antigen (SCCA) has been identified as a hepatitis B virus binding protein and high expression of SCCA has recently been found in hepatocarcinoma. Since HBV is involved in liver carcinogenesis, experiments were carried out to examine the effect of HBV preS1 envelope protein on SCCA expression. Surface and intracellular staining for SCCA was assessed by FACS analysis. Preincubation of HepG2 cells and primary human hepatocytes with preS1 protein or with preS1(21-47) tetrameric peptide significantly increased the surface expression of SCCA, without modification of its overall cellular burden, suggesting a surface redistribution of the serpin. An increase in HBV binding and internalization was observed after pre-incubation of the cells with preS1 preparations, compared to cells preincubated with medium alone. Pretreatment of cells with DMSO, while not influencing SCCA basal expression, was responsible for an increase in the efficiency of HBV internalization and this effect was additive to that obtained after incubation with preS1 preparations. In conclusion, the HBV preS1(21-47) sequence is able to induce overexpression of SCCA at the cell surface facilitating virus internalization, while the increased efficiency of HBV entry following DMSO addition is not mediated by SCCA.
Clinica Medica 5, Università di Padova, via Giustiniani 2, 35128 Padova, Italy.
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Ruvoletto
Clinica Medica 5, Università di Padova, via Giustiniani 2, 35128 Padova, Italy.
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Tono
Immunologia Clinica, Dipartimento di Medicina Clinica e Sperimentale, Università di Padova, via Giustiniani 2, 35128 Padova, Italy.
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Carollo
Clinica Medica 1, Università di Padova, via Giustiniani 2, 35128 Padova, Italy.
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Vilei
Immunologia Clinica, Dipartimento di Medicina Clinica e Sperimentale, Università di Padova, via Giustiniani 2, 35128 Padova, Italy.
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Trentin
Dipartimento di Scienze Mediche e Chirurgiche, Università di Padova, via Giustiniani 2, 35128 Padova, Italy.
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Muraca
Xeptagen Spa, via Olivetti, 1 Pozzuoli (Na), Italy.
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Marino
Clinica Medica 5, Università di Padova, via Giustiniani 2, 35128 Padova, Italy.
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Gatta
Xeptagen Spa, via Olivetti, 1 Pozzuoli (Na), Italy.
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Fassina
Clinica Medica 5, Università di Padova, via Giustiniani 2, 35128 Padova, Italy.
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Pontisso
D000951:Antigens, Neoplasm / Q000235:genetics*; D000954:Antigens, Surface / Q000235:genetics; D014408:Biomarkers, Tumor / Q000235:genetics; D002294:Carcinoma, Squamous Cell / Q000235:genetics* / Q000473:pathology; D045744:Cell Line, Tumor; D017931:DNA Primers; D005434:Flow Cytometry; D015972:Gene Expression Regulation, Neoplastic / Q000235:genetics*; D015967:Gene Expression Regulation, Viral / Q000235:genetics*; D006515:Hepatitis B virus / Q000235:genetics*; D006801:Humans; D016133:Polymerase Chain Reaction; D015843:Serpins
D000951:Antigens, Neoplasm; D000954:Antigens, Surface; D014408:Biomarkers, Tumor; D017931:DNA Primers; D015843:Serpins; C051072:squamous cell carcinoma-related antigen