Expression and clinical significance of co-stimulatory molecule B7-H3 in non-small cell lung cancer

Objective To investigate the expression and clinical significance of co-stimulatory molecule B7-H3 in cell lines and tissues of non-small cell lung cancer(NSCLC).Methods B7-H3 expression was evaluated by flow cytometry,RT-PCR and Western blot in five NSCLC cell lines.Specimens from 87 cases of NSCLC,25 specimens of adjacent non-cancer tissues and 24 specimens of benign lesions of lung were examined immunohistochemically using mouse anti-human B7-H3 monoclonal antibody.The immunohistochemical staining was quantified and mean integrated optical density(mIOD) was measured using Image-Pro Plus software for each section.Results Expression of B7-H3 was found in all five NSCLC cell lines.The mIOD of B7-H3 in 87 NSCLC tissues was higher than that in 25 adjacent non-cancer(P0.001) and in 24 benign lesion samples(P0.001).The sensitivity and the specificity of diagnosis were 67.8% and 93.9% respectively.B7-H3 expression in well differentiated NSCLC was higher than that in not well differentiated one(P0.05).The expression of B7-H3 was not related to gender,age,smoking history,histology and TNM staging(P0.05).Kaplan-Meier analysis revealed that overall survival time of the participants with positive B7-H3 expression was longer than those with negative B7-H3 expression significantly(P0.001).Cox regression analysis suggested that B7-H3-negative expression might be an independent factor affecting the survival time of NSCLC patients.Conclusion B7-H3 is overexpressed in NSCLC tissue and may be an important factor for diagnosis or therapy of the disease.Detection of B7-H3 is helpful to the judgement of the prognosis of NSCLC patients.