Expression Of Survivin And Its Relationship With Expression Of Caspase-7 In Breast Cancer

Objective To explore the expression of a novel inhibitor gene of apoptosis, Survivin,in breast cancer and its relationship with the expression of Caspase-7 and their possible roles in the development and progression of breast cancer. Methods Streptavidin-biotin peroxidase(S-P) method of imunohistochemical staining was used to detect the expression of Survivin and Caspase-7 in 10 hyperplasia tissues of breast louble, 10 simplex hyperplasia tissues of breast duct, 10 dysplasia of adjacent normal breast tissue and 49 breast cancer tissues.Results The Survivin and Caspase-7 positive rates were 63.3% ( 31 /49 ) 67.3% (33/49 ) in 49 cases of breast cancer respectively. In contrast, Survivin was negative in 10 labular hyperplasia , 10 simplex hyperplasia tissues of breast duct, 9 atypical hyperplasia of adjacent normal breast tissues ,whereas Caspase-7 was positively expressed, in a significantly greater proportion of the tissues(100%) than breast cancer(67.3%XP<0.05).There was no relationship between Survivin gene expression with patient's age.tumour size, lymph node metastases, or differentiation, but the expression of Caspase-7 correlated with differentiation of tumorous tissues(P<0.05),namely,the Caspase-7 positive rates in the well-differentiated cancers was higher than in the middle- and poorly-differentiated cancers.Survivin expression was located in cytoplasm or nucleus: 20/30 demonstrated nuclear staining, 3/30 cytoplasmic only.and 8/30 demonstrated both nuclear and cytoplasmic staining, contrasting Caspase-7 expression was mostly found in cytoplasm(27/33).Survivin positive expression was associated with Caspase-7 expression(83.9%,26/31 versus38.9%,7,18XP<0.05).Conclusions ( 1 ) Apoptosis inhibition by Survivin may participate in the onset and progression of breast cancer. Survivin could be a new diagnostic or therapeutic target in breast carcinoma. (2)Survivin positive expression was associated with that of Caspase-7 in breast cancer; moreover,expression of Caspase-7 in the patients with breast carcinoma may be down-regulated with dedifferentiating of the tumor.