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Overexpression of TGFbeta inducible early gene (TIEG1) mimics TGFbeta action and induces apoptosis. In this study, we found that TIEG1 was significantly up-regulated during apoptosis induced by homoharringtonine or velcade. Overexpression of TIEG1 could induce apoptosis in K562 cells and promote apoptosis induced by HHT or velcade. TIEG1-induced apoptosis was shown to involve Bax and Bim up-regulation, Bcl-2 and Bcl-XL down-regulation, release of cytochrome c from mitochondria into the cytosol, activation of caspase 3 and disruption of the mitochondrial membrane potential (DeltaPsim). We concluded that TIEG1 is a key regulator which induces and promotes apoptosis through the mitochondrial apoptotic pathway.

The genetic etiology of hereditary breast cancer has not been fully elucidated. Although germline mutations of high-penetrance genes such as BRCA1/2 are implicated in development of hereditary breast cancers, at least half of all breast cancer families are not linked to these genes. To identify a comprehensive spectrum of genetic factors for hereditary breast cancer in a Chinese population, we performed an analysis of germline mutations in 2,165 coding exons of 152 genes associated with hereditary cancer using next-generation sequencing (NGS) in 99 breast cancer patients from families of cancer patients regardless of cancer types. Forty-two deleterious germline mutations were identified in 21 genes of 34 patients, including 18 (18.2%) BRCA1 or BRCA2 mutations, 3 (3%) TP53 mutations, 5 (5.1%) DNA mismatch repair gene mutations, 1 (1%) CDH1 mutation, 6 (6.1%) Fanconi anemia pathway gene mutations, and 9 (9.1%) mutations in other genes. Of seven patients who carried mutations in more than one gene, 4 were BRCA1/2 mutation carriers, and their average onset age was much younger than patients with only BRCA1/2 mutations. Almost all identified high-penetrance gene mutations in those families fulfill the typical phenotypes of hereditary cancer syndromes listed in the National Comprehensive Cancer Network (NCCN) guidelines, except two TP53 and three mismatch repair gene mutations. Furthermore, functional studies of MSH3 germline mutations confirmed the association between MSH3 mutation and tumorigenesis, and segregation analysis suggested antagonism between BRCA1 and MSH3. We also identified a lot of low-penetrance gene mutations. Although the clinical significance of those newly identified low-penetrance gene mutations has not been fully appreciated yet, these new findings do provide valuable epidemiological information for the future studies. Together, these findings highlight the importance of genetic testing based on NCCN guidelines and a multi-gene analysis using NGS may be a supplement to traditional genetic counseling.

Background: Breast cancer is the chief culprit leading to woman's death. The major cause is the chemoresistance and distant metastasis before or after surgery and standard treatment. Recent studies suggest that chemokines and their receptors may play important roles in breast cancer metastasis and chemoresistance. Purpose: The chemokine receptor CXCR2 is associated with tumor development in many cancers. Although IL-8 and Gro-alpha as the major ligands contribute to breast cancer progression, the function of their receptor CXCR2 in breast cancer is elusive. In this study, we investigated the role of CXCR2 in breast cancer metastasis and chemoresistance. Experimental design:Human breast cancer cell lines including MCF-7 and SKBR-3 (low metastasis), MDA-MB-231 (medium metastasis), MDA-MB-231HM (high lung metastasis), MDA-MB-231BO (high bone metastasis), and MDA-MB-231/Gem (Gemcitabine-resistant) were used to investigate cell proliferation, migration, invasion, colony formation, apoptosis, and tumorigenesis by MTT, scratch-wound, transwell, soft agar, flow cytometery, and animal assays after CXCR2 or its associated proteins were over expressed or silenced/inhibited. Protein expression in cell lines and tissues was examined by either Western blot, ELISA, immunofluorescence, or immunohistochemical staining. Results: CXCR2 expression was higher in chemoresistant breast cancer cell lines, high-metastatic cell lines and breast cancer tissues than in chemosensitive cell lines, low-metastatic cell lines, and breast cancer tissues. Overexpression of CXCR2 promoted cell proliferation, migration, invasion, cell anti-apoptosis, tumor formation, metastasis, and chemoresistance, but silencing of CXCR2 inhibited those activities both in vitro and in vivo. Mechanism studies revealed that CXCR2 suppresses AKT1 to promote breast cancer metastasis and chemoresistance through cyclooxygenase-2 (COX-2; PTGS2) to regulate caveolin-1, MMP2, MMP9, E-cardherin, and beta-catenin, which can be inversed by knock down of CXCR2 or COX-2, and over expression of AKT1 and P85alpha. Additionally, over expression of CXCR2 and COX-2, or silencing of PI3K/AKT1 inhibits p53 phosphorylation (Serine 15) and E2F1 expression, but activates MDM2, Bcl-xL and Bcl-2, leading to increased anti-apoptosis. Tissue microarray analysis from 300 breast cancer patients also indicated that over expression of CXCR2 is associated with enhanced COX2 expression and reduced AKT1 expression in metastatic and chemoresistant breast carcinomas (P < 0.001), which may be used to predict breast cancer development. Conclusions: Our results suggest that CXCR2 controls breast cancer metastasis and chemoresistance through regulating COX-2 and AKT1. Thus, antagonists of CXCR2 and COX-2 may be used synergistically to treat breast cancer patients particularly with high metastasis and chemoresistance. Citation Format: Han Xu, Fengjuan Lin, Ziliang Wang, Jiao Meng, Huizhen Sun, Zihao Qi, Yan Wang, Zhouluo Ou, Zhimin Shao, Genhong Di, Gong Yang. CXCR2 controls breast cancer metastasis and chemoresistance through PI3K/AKT and COX-2 signalings. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 548. doi:10.1158/1538-7445.AM2013-548 Note: This abstract was not presented at the AACR Annual Meeting 2013 because the presenter was unable to attend.

e11567 Background: This phase II study was to explore the efficacy and safety of weekly nab-paclitaxel and cisplatin combinationin Chinese advanced breast cancer (ABC) patients. While all other safety profiles were similar and expected based on published clinical trial results conducted in Western patients, the incidence of skin rash was unexpectedly higher. Methods: Nab-paclitaxel(125 mg/m2) was administered on days 1, 8, 15, followed by cisplatin (75 mg/m2) on day 1 every 28 day cycle until disease progression, intolerable toxicities or the maximum of 6 cycles. Patients who received at least one injection of the study drug were included in this analysis of the incidence of skin rash among Chinese patients. Toxicity was graded using the CTCAE4.0. The incidences of skin toxicity with conventional- and nab-paclitaxel were obtained from published trial results in both Chinese and Western patients. Results: 73 patients enrolled were qualified to be analyzed, and a total of 384 cycles were administered before the datalock on Oct 1st, 2011. Rash was presented in 27 patients (37.0%). The most common sites involved were face (14/27), neck (14/27), limbs (18/27) and frictional parts of the trunk (10/27). Macular and papular rash with pruritus commonly occurred 2 (1-7) days after the first day of chemotherapy. Only one patient developed Grade 3 skin toxicity with generalized erythroderma and disfigurement of the face requiring dose reduction. The rash gradually regressed 2 (1-10) days after antihistamines using and pigmentation remained in 13/27 cases. The incidence rate of skin toxicity was significantly higher in Chinese patients than Western counterparts (P

Background Few studies have addressed the biological features of medullary breast carcinoma (MBC) in the context of clinical outcomes. We sought to compare the baseline demographics, standard pathologic factors and long-term clinical outcomes between MBC and infiltrating ductal carcinoma-not otherwise specified (IDC-NOS) using a large database. Methods A total of 2,202 cases with pure IDC-NOS and 188 cases with typical MBC meeting the inclusion criteria were identified. The clinical and biological features, the overall survival (OS) and recurrence/metastasis-free survival (RFS) were compared for both groups. Results There were a higher proportion of patients diagnosed prior to 40 years of age in the MBC group compared to the IDC-NOS group. MBC cases demonstrated less aggressive tumor features such as lower tumor stage, smaller tumor size and a lower proportion of nodal involvement than IDC-NOS; however, immunohistochemical staining revealed that MBC displayed the triple-negative phenotype more often than IDC-NOS cases (40.4% versus 26.2%; P P = 0.032) and death (P = 0.042) than those with IDC-NOS, and the 10-year OS and RFS were significantly higher for MBC (91% and 74%) compared to IDC-NOS (81% and 64%). Moreover, multivariate analysis revealed that TNM stage was a statistically significant factor for survival. Conclusions MBC in Chinese women demonstrated less aggressive behavior and better prognosis than IDC-NOS. This favorable outcome was maintained after 10 years.

Background We sought to compare the baseline demographics, standard pathologic factors and long- term clinical outcomes between ILC and infiltrating ductal carcinoma (IDC) using a large database. Methods Clinicopathologic features, overall survival (OS), and recurrence/metastasis-free survival (RFS) were compared between 2,202 patients with IDC and 215 patients with ILC. Results ILC was significantly more likely to be associated with a favorable phenotype, but the incidence of contralateral breast cancer was higher for ILC patients than for IDC patients (8.4% vs. 3.9%; P =0.001). The frequencies of recurrence/metastasis (P = 0.980) and death (P = 0.064) were similar among patients with IDC and patients with ILC after adjustment for tumor size and nodal status. The median follow-up was 42.8 months. Conclusions Chinese women with ILCs do not have better clinical outcomes than their counterparts with IDC. Management decisions should be based on individual patient and tumor biologic characteristics, and not on lobular histology.