Study On Frequency And Significance Of Breast Cancer Susceptibility Gene BRCA1 Mutation In Uigur Women In Xinjiang

Objective : The breast cancer susceptibility gene BRCA1 mutation was varies in different areas and ethnic people. By investigating the frequency and spectrum of BRCA1 mutation in breast cancer in Uigur and Han women ,and study the the biological characteristics of BRCA1 mutation associated breast cancer, All of them could help to further study the genetic carcinogenic genesis of breast cancer in Uigur women in Xinjiang.Methods: By using single strand conformational polymorphism (SSCP) and DNA sequencing, BRCA1 mutation were detected in 70 cases Uigur ,40 cases Han women breast cancer and 32 cases benign breast diseases and non-tumor tissue next to carcinoma. The expression of BRCA1, P53 and ki-67 protein were detected immunohistochemically by Envision method in 110 cases of breast cancer. Results: (1) BRCAl mutation was detected in 13 of 110 cases (11.82%) of Uigur and Han women sporadic breast cancer. In 70 cases of Uigur women breast cancer, the rate of BRCAl mutation was 15.71% (11/70). The frequency of BRCA1 mutation in Uigur women Early onset breast cancer(8/22) was higher than that in Late onset group (3/48) (X~2=8.18 p<0.01) .(2) 18 loci of BRCA1 mutation were detected firstly in 13 cases Uigur and Han women breast cancer, the loci of BRCA1 mutation had not been reported. Among them, the mutations new loci IVS20-68insA were detected in 3 cases Uigur women and 1 cases Han women breast cancer, the mutations new loci 3538insT were detected in 2 cases of Uigur women early onset breast cancer. (3)There were BRCA1 gene polymorphisms in 11 of 110 sporadic breast cancer patients, including 9 cases Uigur women and 2 cases Han women. (4) All the benign breast diseases BRCA1 protein localized mainly in nuclear, among them 26 cases expressed in both nuclear and cytoplasm. However , BRCA1 protein localized in cytoplasm in all 105 cases of breast cancer(105/110). Comparing to non-BRCA1 mutation group , BRCA1 mutation associated breast cancer were higher in the histological grade, P53 positive rate and lymphatic metastases, and was younger in the age of the patients.Conclusion: (1) The frequency of BRCAl mutation was 15.71% (11/70) in 70 cases of Uigur women sporadic breast cancer, The frequency of BRCA1 mutation in Uigur women Early onset breast cancer (8/22) was higher than that in Late onset group (3/48). There were BRCAl gene polymorphisms in 9 of 70...