Implications of the Notch1-Snail/Slug-epithelial to mesenchymal transition axis for lymph node metastasis in infiltrating ductal carcinoma.

Emerging evidence suggests that activation of the Notch1 signaling pathway inducing epithelial to mesenchymal transition (EMT) mediated by Snail/Slug promotes invasion and metastasis of breast cancer cells in vitro. However, the implication of the Notch1-Snail/Slug-EMT axis in breast cancer patients remains unclear. A total of 200 formalin-fixed paraffin-embedded samples of invasive ductal carcinoma (IDC), and 37 adjacent non-neoplastic tissue (ANNT) samples from patients who had not been treated with neoadjuvant therapy were examined. Expression of Notch1, Slug, Snail, E-cadherin, N-cadherin, and vimentin was determined by immunohistochemistry on tissue microarrays (TMAs). The correlation between protein expression and clinicopathological characteristics of breast cancer patients was also evaluated. Results showed that a significantly high percentage of cases with high expression of Notch1 (74%, 148/200), Slug (36%, 72/200), Snail (62%, 124/200), and N-cadherin (77%, 153/200) and a low percentage of cases with high expression of E-cadherin (27%, 54/200) were observed in IDC compared to those in ANNTs. High Notch1, Slug, Snail, and N-cadherin expression and low E-cadherin expression in patients with IDC were significantly correlated with lymph node metastasis. In addition, correlation analysis results revealed that high Notch1 expression was significantly associated with high Slug, Snail, and N-cadherin expression and low E-cadherin expression in IDC. Furthermore, a high Snail expression was significantly associated with low E-cadherin expression, and a high Slug expression was found to be significantly associated with increased N-cadherin expression in patients with IDC. Hence, our study suggested that the Notch1-Snail/Slug-EMT axis may be implicated in the lymph node metastasis affecting patients with IDC.

BRCA1 gene exon 11 mutations in Uighur and Han women with early-onset sporadic breast cancer in the northwest region of China.

The prevalence of BRCA1 gene mutations in breast cancer differs between diverse ethnic groups. Relatively little information is known about patterns of BRCA1 mutations in early-onset breast cancer in women of Uighur or Han descent, the major ethnic populations of the Xinjiang region in China. The aim of this study was to identify BRCA1 mutations in Uighur and Han patients with early-onset (age <35 years), and sporadic breast cancer for genetic predisposition to breast cancer. For detection of BRCA1 mutations, we used a polymerase chain reaction single-stranded conformation polymorphism approach, followed by direct DNA sequencing in 22 Uighur and 13 Han women with early-onset sporadic breast cancer, and 32 women with benign breast diseases. The prevalence of BRCA1 mutations in this population was 22.9% (8/35) among early-onset sporadic breast cancer cases. Of these, 31.8% (7/22) of Uighur patients and 7.69% (1/13) of Han patients were found to have BRCA1 mutations. In 7 Uighur patients with BRCA1 mutations, there were 11 unique sequence alterations in the BRCA1 gene, including 4 clearly disease-associated mutations on exon 11 and 3 variants of uncertain clinical significance on exon 11, meanwhile 4 neutral variants on intron 20 or 2. None of the 11 BRCA1 mutations identified have been previously reported in the Breast Cancer Information Core database. These findings reflect the prevalence of BRCA1 mutations in Uighur women with early-onset and sporadic breast cancer, which will allow for provision of appropriate genetic counseling and treatment for Uighur patients in the Xinjiang region.

[Analysis of the mutation of BRCA1 gene in 70 Uigur women breast cancer patients in Xinjiang].

OBJECTIVE: To analyze the mutations of BRCA1 in breast cancer patients of Uigur women in Xinjiang. METHODS: By using single strand conformation polymorphism (SSCP) and DNA sequencing, BRCA1 mutations were detected in 70 Uigur women breast cancer cases and 32 cases of benign breast diseases and non-tumor tissue next to carcinoma. RESULTS: (1) 12 new loci of BRCA1 gene mutation were detected firstly in 70 Uigur women breast cancer patients. (2)The frequency of BRCA1 mutation in 70 Uigur women breast cancer cases was 12.86% (9/70). The frequency of BRCA1 mutation in Uigur women early onset breast cancer was 31.82% (7/22), which was significantly higher than that in late onset group (2/48, 4.16%) (chi(2) =10.295, P<0.01). (3) There were BRCA1 gene polymorphisms in 9 of 70 Uigur women breast cancer patients. The loci of polymorphisms in 8 of 9 cases were 3232A>G. (4)In the research group two cases of bilateral breast cancer were found with BRCA1 gene mutation. CONCLUSION: The mutation of BRCA1 gene may be related to Uigur women breast cancer and bilateral breast cancer.