The expression of A3B in breast cancer was higher than in non-cancerous tissues and was related to the lymph node metastasis and nuclear grade, which are reliable aggressive phenotype markers in breast cancer. Evaluation of A3B expression in tumor may be a marker for breast cancer with malignant potential.

Estrogen is a key regulator of the proliferation and differentiation of breast cancer cells. In addition to the estrogen supply from the ovary, estrogen is produced locally from androgen by aromatase. However, the regulation of aromatase gene expression in breast cancer has not yet been fully clarified. Retinoic acid receptor-related orphan receptor (ROR) ␣ plays an important role in the differentiation of many organs by regulating the transcription of target genes. Because aromatase and ROR␣ are expressed in breast cancer, the effect of ROR␣ on aromatase gene expression was studied. ROR␣ significantly augmented the expression of aromatase mRNA, particularly those containing exon I.4, in MCF7 cells, and aromatase activities in T47D and MCF7 cells. ROR␣ also stimulated the proliferation of these cells. Transient transfection-based reporter gene assays using the promoter at exon I.4 showed that ROR␣ augmented the transcription. A series of truncated mutation studies revealed that ROR␣ activated the transcription through ؊147 to ؉14 bp of the promoter I.4. Furthermore, ROR␣ bound to the fragment containing ؊119 to ؊107 bp of the promoter in vitro, indicating that this region may contain a novel ROR response element. Chromatin immunoprecipitation assay showed that ROR␣ bound to the region containing this site of the promoter I.4 in MCF7 cells. Moreover, we examined clinical samples and found a correlation between ROR␣ and aromatase expression. These results suggest that ROR␣ directly activates the aromatase expression to accelerate the local production of estrogen, which results in the proliferation of breast cancer cells.

Ki-67 LI is a strong prognostic factor in ER-positive HER2-negative breast cancer. Topo IIa overexpression was significantly correlated with the Ki-67 LI, nuclear grade, and LVI. These findings suggest use of Topo IIa expression as a proliferation marker and a prognostic factor in ER-positive, HER2-negative breast cancer.

Biomarkers that can accurately predict treatment response are required for indicating optimal neoadjuvant treatments. The current study assessed the predictive value of secreted protein acidic and rich in cysteine (SPARC) mRNA expression for the response to neoadjuvant nab-paclitaxel (nab-PTX) therapy in patients with breast cancer. It was hypothesized that SPARC expression can affect the response to albumin-bound taxanes, including nab-PTX since SPARC binds albumin with a high affinity. Pre-therapeutic specimens of core needle biopsies were analyzed from 50 patients in a phase II trial of neoadjuvant nab-PTX and the factors that were associated with a pathological complete response (pCR) were assessed. The pre-therapeutic tumor mRNA levels of chemotherapy-related proteins were quantified, including SPARC, and the correlations with post-therapeutic clinicopathological factors were assessed, including with pCR. The results demonstrated that pre-therapeutic SPARC mRNA expression was significantly higher in non-pCR patients compared with patients with pCR (92.37±55.33 vs. 56.53±30.19; P=0.027). A cutoff point of 48.5 was determined using receiver operating characteristic (ROC) curve analysis (sensitivity, 83.3%; specificity, 50.0%), and patients were classified into low and high SPARC expression groups. High SPARC expression was associated with histological grade (P=0.035), estrogen receptor expression (P=0.037), and progesterone receptor expression (P=0.002) but not with HER2 (P=0.895), and Ki-67 LI (P=0.743) expression. The results of the current study indicated that a high SPARC mRNA expression was a negative predictor of pCR following neoadjuvant nab-PTX therapy regardless of breast cancer subtype. The phase II study was conducted in accordance with the Declaration of Helsinki, and the protocol was approved by the Ethics Committee of the National Hospital Organization Takasaki General Medical Center (Registration nos. H23-9 and H23-33).

Abstract. Papillary lesions of the breast include a broad spectrum of lesions, from benign papillomas to papillary carcinomas. It is difficult to determine whether a lesion is benign or malignant based on the fragmented material of a core needle biopsy (CNB). This study evaluated patients with papillary lesions examined using CNB. We retrospectively reviewed 31 papillary lesions diagnosed using CNB between 2004 and 2007. The clinical findings of benign and malignant papillary lesions were compared. The average patient age was 48.9 years. Twelve patients presented with a discharge and 10 patients presented with a lump. Eight patients were asymptomatic. The initial diagnoses by CNB of the 31 lesions were 25 intraductal papillomas, 4 intracystic papillomas and 2 adenomas. After CNB, excisional biopsies were performed in 23 patients and biopsies with a Mammotome ® in 2 patients. Seven patients underwent regular follow-up. Five (16%) of the 31 patients with papillary lesions were ultimately diagnosed with breast cancer. The average distance from the nipple to a tumor diagnosed as malignant was 2.46 cm, which was longer than for a tumor diagnosed as benign. Ultimately, 5 papillary lesions (16%) were diagnosed as breast cancer. To avoid overlooking a malignancy, surgical excision is advantageous for papillary lesions, particularly those located far from the nipple.