Yu et al. Journal of Experimental & Clinical Cancer Research 2010, 29:107 http://www.jeccr.com/content/29/1/107 Page 5 of 7 Table 3 The relationship between the expression of BCL-2, BAD and the histologic grade, clinical TNM stages and the axillary lymph nodes metastasis in youth and menopause breast cancer tissues Total Histologic grade Clinical TNM stage Axillary lymph nodes Positive Negative Youth breast cancer tissues BCL-2+ BCL-2- +% BAD+ BAD- +% Menopause breast cancer tissues BCL-2+ BCL-2- +% BAD+ BAD- +% 40 19 21 47.5% 12 28 30.0% 40 30 10 75.0% 25 15 62.5% I 8 7 1 87.5%1 4 4 50.0%2 18 16 2 88.9%2 11 7 61.1%2 II 27 12 15 44.4% 8 19 29.6% 19 14 5 73.7% 13 6 68.4% III 5 0 5 0.0% 0 5 0.0% 3 0 3 0.0% 1 2 33.3% I 6 4 2 66.7%3 2 4 33.3%3 5 4 1 80.0%3 4 1 80.0%3 II 25 12 13 48.0% 8 17 32.0% 22 17 5 77.3% 15 7 68.2% III 8 3 5 37.5% 2 6 25.0% 11 8 3 72.7% 6 5 54.5% IV 1 0 1 0.0% 0 1 0.0% 2 1 1 50.0% 0 2 0.0% 19 3 16 15.8%4 6 13 31.6%5 10 2 8 20.0%4 5 5 50.0%5 21 16 5 76..2% 6 15 28.6% 30 28 2 93.3% 20 10 66.7% Compare with each other in the same group:1: P < 0.01,2: P > 0.05,3: P > 0.05,4: P < 0.01,5: P > 0.05 Discussion BCL-2 is a gene of anti-apoptosis, the mechanism is possibly related to affect Ca2+ entering the cell, thereby regulating the signal transduction in the cells[2]. BAD and BCL-2 are all members of BCL-2 gene family, and the role of BAD is to promote apoptosis, BAD genes induced apoptosis through to form heterodimers with BCL-2, thus inhibited the anti-apoptotic role of BCL-2 [3] The researches on gastrointestinal tumors, and kid- ney tumors have found that high expression of BCL-2 of inhibitor of apoptosis, induced tumor growth acceler- ated, the poor prognosis and poor response to treatment [4,5]. In this study we find that the expression of BCL-2, BAD in tissues of breast carcinoma are significantly lower than tissues of normal breast and tissues of breast fibroma. Compared with menopause breast carcinoma, youth breast carcinoma shows higher malignant degree, the invasion is stronger, the transfer rate is higher, the prog- nosis is worse [6]. In this study we found that the expression rates of BCL-2 and BAD in tissues of youth breast carcinoma were significantly lower than in the tissues of menopause breast carcinoma. In breast cancer Table 4 The relationship between the expression of BCL-2, BAD and the expression of ER, PR. Total ER(+)PR(+) ER(+)PR(-) ER(-)PR(+) ER(-)PR(-) Bcl-2(+)Bad(+) Bcl-2(+)Bad(-) Bcl-2(-)Bad(+) Bcl-2(-)Bad(-) 9 40 22 9 6(66.7%)a 18(45.0%) 6(27.3%) 0(0.0%) 2(22.2%)b 10(25.0%) 7(31.8%) 1(11.1%)f 1(11.0%)c 7 (17.5%) 8(36.4%) 0(0.0%)g 0(0.0%)d 5 (12.5%) 1(4.5%) 8(88.9%)h a compared b.c.d P < 0.05; h comparede.f.g P < 0.05. histologic grade I to III the expression of BCL-2 assumed the decreasing tendency, the differences had significant difference, the expresses of BAD during this process also gradually reduced. The expression of BCL-2 in breast cancer tissues with axillary lymph node metas- tasis were significantly lower than that without lymph node metastasis. The expression of BAD in the tissues of breast carcinoma and axillary lymph node metastasis showed no correlation obviously, the expression of BCL- 2 and BAD were no significant difference in the clinical TNM staging of breast carcinoma. The above data showed that the expression of the two genes played an important role in the occurrence and development of the breast carcinoma; and the changes of BCL-2 and BAD occured in the early stage of the breast carcinoma. This study showed that the expression of BCL-2 and the expression of ER and PR were highly correlated. In the ER and PR-positive groups, the expression of BCL-2 was significantly higher than that of its negative group; But the expression of BAD showed no significant corre- lation with the expression of ER and PR. Compare with the BCL-2 negative group, the expression Of ER and PR were higher in the BCL-2 positive group. When the expression of BCL-2 and BAD were positive, at the same time the expression of ER and PR were especially high. Milella [7]. also confirmed that the expression of BCL-2 was regulated by estrogen. The expression of BCL-2 most confined to the ER-positive breast cancer cells, ER-positive was a necessary condition in endocrine therapy; the patient with BCL-2 high expression having a good prognosis, maybe more sensitivity to endocrine therapy. The expression of BCL-2 and BAD can be used as prognosis factors of breast cancer. Detecting the