Expression And Significance Of EGFR And C-erbB-2 In Primary Osteosarcoma

[Objective]To discuss the expression of EGFR and C-erbB-2 protein expression in primary osteosarcoma,as well as the relationship between the two proteins. At the same time, detect the two proteins in osteosarcoma cell line SaOS-2.[Methods]PV-9000 general-purpose application of two-step immunohistochemical method was used to determine the expression of EGFR and C-erbB-2 protein in 20 cases of primary osteosarcoma and 10 cases of fibrous dysplasia respectively. Then, detected the two protein indictors in osteosarcoma cell line SaOS-2.At last, using the SPSS13.0 statistical software to process the data, the FishEr test in groups and spearman correlation analysis to statistically analyze the data.[Results]1)The expression of EGFR in primary osteosarcoma:10 of 20 cases appear to be positive in primary osteosarcoma whose positive rate was 50.0%, significantly higher than that of fibrous dysplasia whose positive rate was 10%(1/10); Statistical significance was found between them by FishEr test (P<0.05).2) The expression of C-erbB-2 in primary osteosarcoma:8 of 20 cases were shown C-erbB-2 protein positive expression, the positive rate was 40%, significantly higher than that of fibrous dysplasia 0%(0/10). Statistical significance were found between them by FishEr test (P<0.05). (P<0.05).3)The relationship between of EGFR and C-erbB-2 protein in primary osteosarcoma:in the 20 cases of primary osteosarcoma, there are 10 cases showing EGFR positive and within the 10 positive cases, there are 7 cases expressing C-erbB-2.Within the ten EGFR-negative cases, all of them show C-erbB-2 negative, too.4) In osteosarcoma cell line SaOS-2,the EGFR positive rate is 67.33±0.58%(P< 0.05)and that of C-erbB-2 is 36.80±5.88%(P<0.05)[Conclusion]1)EGFR is the product of proto-oncogene C-erbB-1.In the study we found that EGFR expression was significantly higher in primary osteosarcoma, suggesting there maybe over-express of EGFR in osteosarcoma. Maybe the EGFR-mediated signal transduction pathway take part in the occurrence and progression of osteosarcoma.2) In primary osteosarcoma, C-erbB-2 protein expression was significantly increased. In the 8 cases, there are 7 cases showing plasm positive and 1 case typically membrane positive which diagnosed as Chondroblastic osteosarcoma by pathologist. We plan to increase the samples to detect C-erbB-2 expression to decide whether there are difference in various types of osteosarcoma nor not.3) Spearman rank correlation analysis showed that there was significantly positive correlation between expression of EGFR and C-erbB-2 (r=0.834, P<0.001).But there was no relevance between them in fibrous dysplasia, because the C-erbB-2 positive rate was 0%(0/10). From above on, we can conclude that there was co-expression of EGFR and C-erbB-2 in primary osteosarcoma, which may be provide some experimental data for the early diagnosis, treatment or prognosis in osteosarcoma.4) Both EGFR and C-erbB-2 overexpress in osteosarcoma cell line SaOS-2, but their mechanism in SaOS-2 should be researched with molecular biology methods.