Transcriptome sequencing of HER2-positive breast cancer stem cells identifies potential prognostic marker.

In cancer stem cell theory, breast cancer stem cells (BCSCs) are postulated to be the root cause of recurrence and metastasis in breast cancer. Discovery of new biomarkers and development of BCSC-targeted therapy are practical issues that urgently need to be addressed in the clinic. However, few breast cancer stem cell targets are known. Given that there are few BCSCs, performing transcriptome sequencing on them thus far has not been possible. With the emergence of single-cell sequencing technology, we have now undertaken such a study. We prepared single-cell suspensions, which were sorted using flow cytometry from breast tumor tissue and adjacent normal breast tissue from two HER2-positive patients. We obtained BCSCs, breast cancer cells, mammary cells, and CD44+ mammary cells. Transcriptome sequencing was then performed on these four cell types. Using bioinformatics, we identified 404 differentially expressed BCSC genes from the HER2-positive tumors and preliminary explored transcriptome characteristics of BCSCs. Finally, by querying a public database, we found that CA12 was a novel prognostic biomarker in HER2-positive breast cancer, which also had prognostic value in all breast cancer types. In conclusion, our results suggest that CA12 may be associated with BCSCs, especially HER2-positive BCSCs, and is a potential novel therapeutic target and biomarker.

Covariation of copy number located at 16q22.1: new evidence in mammary ductal carcinoma.

Copy number variation (CNV) is crucial for gene regulation in humans. A number of studies have revealed that CNV contributes to the initiation and progression of cancer. In this study, we analysed four breast cancer cell lines and six fresh frozen tissues from patients to evaluate the CNV present in the genome using microarray-based comparative genomic hybridization (aCGH). Six genes located at 16q22.1 were analysed by real-time PCR. The real-time PCR analysis revealed that the loss of CDH1/E2F4 may be associated with worse clinical and pathological findings. Interestingly, covariation of CDH1, CDH3, CTCF and E2F4 was found to be associated with triple negative breast cancer and HER-2 receptor status. In conclusion, our study supports the idea that CNV at 16q22.1 in breast cancer is a frequent event; furthermore, it reveals the covariation of CDH1, CDH3, CTCF and E2F4. The role of the covariation is more complex than a simple additive effect of these four separate genes, which may provide a novel target for breast cancer.

Breast cancer in 65-year-old or older patients: clinicopathological characteristics and prognosis.

BACKGROUND: The number of 65-year-old or older patients with breast cancer is increasing. Here we describe the clinicopathological features and prognosis of these patients. PATIENTS AND METHODS: We reviewed the records of 1,651 consecutive patients aged > 50 years with a first diagnosis of invasive breast cancer who were referred to surgery between March 1999 and December 2005. Of these patients, 224 were aged ≥ 65 years (group I) and 1,427 were aged 51-64 years (group II). RESULTS: Compared with patients of group II, patients of group I had a higher percentage of tumors classified as estrogen receptor (ER) positive (p = 0.009), progesterone receptor (PR) negative (p = 0.044), and with a Ki-67 labeling index ≥ 20% of the cells (p = 0.015). There was no difference between the 2 groups for pT, pN, histology, endocrine therapy, radiotherapy, and chemotherapy. The 5-year survival of group I was 80.1% as compared with 86.2% for group II (p = 0.018). CONCLUSION: Compared with patients aged between 51 and 64 years, patients aged ≥ 65 years have a greater chance of having tumors that are ER positive, PR negative, with a Ki-67 labeling index ≥ 20% of the cells and a significantly poorer prognosis.

Fangchinoline inhibits breast adenocarcinoma proliferation by inducing apoptosis.

Radix Stephaniae tetrandrae, which contains tetrandrine (Tet) and fangchinoline, is traditionally used as an analgesic, antirheumatic, and antihypertensive drug in China. In this study, we investigated its effect on breast cancer cell proliferation and its potential mechanism of action in vitro. Treatment of cells with fangchinoline significantly inhibited MDA-MB-231 cell proliferation in a concentration- and time-dependent manner. To define the mechanism underlying the antiproliferative effects of fangchinoline, we studied its effects on critical molecular events known to regulate the apoptotic machinery. Specifically, we addressed the potential of fangchinoline to induce apoptosis of breast cancer cells. Fangchinoline induced internucleosomal DNA fragmentation, chromatin condensation, activation of caspases-3, -8, and -9, and cleavage of poly(ADP ribose) polymerase, as well as enhanced mitochondrial cytochrome c release. Furthermore, fangchinoline increased the expression of the proapoptotic protein B cell lymphoma-2 associated X (Bax) and decreased the expression of the antiapoptotic protein B cell lymphoma-2 (Bcl-2). In addition, the proliferation-inhibitory effect of fangchinoline was associated with decreased levels of phosphorylated Akt. Our results indicate that fangchinoline can inhibit breast cancer cell proliferation by inducing apoptosis via the mitochondrial apoptotic pathway and decreasing phosphorylated Akt. Thus fangchinoline may be a novel agent that can potentially be developed clinically to target human malignancies.