AIM:To investigate the role of osteopontin(OPN) and its splice variants in the proliferation of hepatocellular carcinoma(HCC).METHODS:The expression of OPN variants in HCC cell lines as well as HCC tissue samples and ...AIM:To investigate the role of osteopontin(OPN) and its splice variants in the proliferation of hepatocellular carcinoma(HCC).METHODS:The expression of OPN variants in HCC cell lines as well as HCC tissue samples and nontumour tissue was studied using polymerase chain reaction.OPN variant cDNAs were cloned into a mammalian expression vector allowing both transient expression and the production of stable OPN expressing cell lines.OPN expression was studied in these cells using Western blotting,immunofluoresnce and enzyme linked immunosorbent assay.A CD44 blocking antibody and siRNA targeting of CD44 were used to examine the role of this receptor in the OPN stimulated cell growth observed in culture.Huh-7 cells stably expressing either OPN-A,-B or-C were injected subcutaneously into the flanks of nude mice to observe in vivo tumour growth.Expression of OPN mRNA and protein in these tumours was examined using reverse transcriptionpolymerase chain reaction and immunohistochemistry.RESULTS:OPN is expressed in HCC in 3 forms,the full length OPN-A and 2 splice variants OPN-B and-C.OPN variant expression was noted in HCC tissue as well as cognate surrounding cirrhotic liver tissue.Expression of these OPN variants in the HCC derived cell line Huh-7 resulted in secretion of OPN into the culture medium.Transfer of OPN conditioned media to na ve Huh-7 and HepG2 cells resulted in significant cell growth suggesting that all OPN variants can modulate cell proliferation in a paracrine manner.Furthermore the OPN mediated increase in cellular proliferation was dependent on CD44 as only CD44 positive cell lines responded to OPN conditioned media while siRNA knockdown of CD44 blocked the proliferative effect.OPN expression also increased the proliferation of Huh-7 cells in a subcutaneous nude mouse tumour model,with Huh-7 cells expressing OPN-A showing the greatest proliferative effect.CONCLUSION:This study demonstrates that OPN plays a significant role in the proliferation of HCC through interaction with the cell surface receptor C展开更多
OBJECTIVE: To investigate the expression of cluster of differentiation 44 variant 6 (CD(44V6)) and proliferating cell nuclear antigen (PCNA) in ocular squamous cell carcinomas. METHODS: Streptavidin-biotin complex (SA...OBJECTIVE: To investigate the expression of cluster of differentiation 44 variant 6 (CD(44V6)) and proliferating cell nuclear antigen (PCNA) in ocular squamous cell carcinomas. METHODS: Streptavidin-biotin complex (SABC) immunohistochemistry was used to explore the expression of CD(44V6) and PCNA in 35 cases of ocular squamous cell carcinomas, 20 cases of papillomas, and 11 cases of normal eyelid tissue. RESULTS: The CD(44V6) positive rate was 62.9% (22/35) in ocular squamous cell carcinomas, 15.0% (3/20) in papillomas, but not detectable in the 11 cases of normal eyelid tissue. The positive expression rates of CD(44V6) in ocular squamous cell carcinomas were significantly higher than in benign tumors (chi(2) = 11.57, P展开更多
文摘AIM:To investigate the role of osteopontin(OPN) and its splice variants in the proliferation of hepatocellular carcinoma(HCC).METHODS:The expression of OPN variants in HCC cell lines as well as HCC tissue samples and nontumour tissue was studied using polymerase chain reaction.OPN variant cDNAs were cloned into a mammalian expression vector allowing both transient expression and the production of stable OPN expressing cell lines.OPN expression was studied in these cells using Western blotting,immunofluoresnce and enzyme linked immunosorbent assay.A CD44 blocking antibody and siRNA targeting of CD44 were used to examine the role of this receptor in the OPN stimulated cell growth observed in culture.Huh-7 cells stably expressing either OPN-A,-B or-C were injected subcutaneously into the flanks of nude mice to observe in vivo tumour growth.Expression of OPN mRNA and protein in these tumours was examined using reverse transcriptionpolymerase chain reaction and immunohistochemistry.RESULTS:OPN is expressed in HCC in 3 forms,the full length OPN-A and 2 splice variants OPN-B and-C.OPN variant expression was noted in HCC tissue as well as cognate surrounding cirrhotic liver tissue.Expression of these OPN variants in the HCC derived cell line Huh-7 resulted in secretion of OPN into the culture medium.Transfer of OPN conditioned media to na ve Huh-7 and HepG2 cells resulted in significant cell growth suggesting that all OPN variants can modulate cell proliferation in a paracrine manner.Furthermore the OPN mediated increase in cellular proliferation was dependent on CD44 as only CD44 positive cell lines responded to OPN conditioned media while siRNA knockdown of CD44 blocked the proliferative effect.OPN expression also increased the proliferation of Huh-7 cells in a subcutaneous nude mouse tumour model,with Huh-7 cells expressing OPN-A showing the greatest proliferative effect.CONCLUSION:This study demonstrates that OPN plays a significant role in the proliferation of HCC through interaction with the cell surface receptor C
文摘OBJECTIVE: To investigate the expression of cluster of differentiation 44 variant 6 (CD(44V6)) and proliferating cell nuclear antigen (PCNA) in ocular squamous cell carcinomas. METHODS: Streptavidin-biotin complex (SABC) immunohistochemistry was used to explore the expression of CD(44V6) and PCNA in 35 cases of ocular squamous cell carcinomas, 20 cases of papillomas, and 11 cases of normal eyelid tissue. RESULTS: The CD(44V6) positive rate was 62.9% (22/35) in ocular squamous cell carcinomas, 15.0% (3/20) in papillomas, but not detectable in the 11 cases of normal eyelid tissue. The positive expression rates of CD(44V6) in ocular squamous cell carcinomas were significantly higher than in benign tumors (chi(2) = 11.57, P
