Hormonally regulated survival factors can have an important role in breast cancer. Here we elucidate G1P3, a survival protein induced by interferons (IFNs), as a target of estrogen signaling and a contributor to poor outcomes in estrogen receptor-positive (ER þ ) breast cancer. Compared with normal breast tissue, G1P3 was upregulated in the malignant epithelium (50 Â higher) and was induced by estrogen ex vivo. In accord with its overexpression in early stages of breast cancer (hyperplasia and ductal carcinoma in situ), in morphogenesis assays G1P3 enhanced the survival of MCF10A acinar luminal cells causing hyperplasia by suppressing detachmentinduced loss of mitochondrial potential and apoptosis (anoikis). In cells undergoing anoikis, G1P3 attenuated the induction of Bim protein, a proapoptotic member of the Bcl-2 family and reversed the downmodulation of Bcl-2 protein. Downregulation of G1P3 induced spontaneous apoptosis in BT-549 breast cancer cells and significantly reduced the growth of ER þ breast cancer cell MCF7 (Pp0.01), further suggesting its prosurvival activity. In agreement with its induction by estrogen, G1P3 antagonized tamoxifen, an inhibitor of ER in MCF7 cells. More importantly, elevated expression of G1P3 was significantly associated with decreased relapsefree and overall survival in ER þ breast cancer patients (Pp0.01). Our studies suggest that elevated expression of G1P3 may perturb canonical tumor-suppressing activity of IFNs partly by affecting the balance of pro-and antiapoptotic members of Bcl-2 family proteins, leading to breast cancer development and resistance to therapies.

Background:Although inhibitors of histone deacetylase inhibitors (HDACis) in combination with genotoxins potentiate apoptosis, the role of proteases other than caspases in this process remained elusive. Therefore, we examined the potentiation of apoptosis and related mechanisms of HDACis and doxorubicin combination in a panel of myeloma cell lines and in 25 primary myelomas.Results:At IC50 concentrations, sodium butyrate (an HDACi) or doxorubicin alone caused little apoptosis. However, their combination potentiated apoptosis and synergistically reduced the viability of myeloma cells independent of p53 and caspase 3–7 activation. Potentiated apoptosis correlated with nuclear translocation of apoptosis-inducing factor, suggesting the induction of caspase 3- and 7-independent pathways. Consistent with this, butyrate and doxorubicin combination significantly increased the activity of cytoplasmic cathepsin B. Inhibition of cathepsin B either with a small-molecule inhibitor or downregulation with a siRNA reversed butyrate- and doxorubicin-potentiated apoptosis. Finally, ex vivo, clinically relevant concentrations of butyrate or SAHA (suberoylanilide hydroxamic acid, vorinostat, an HDACi in clinical testing) in combination with doxorubicin significantly (P<0.0001) reduced the survival of primary myeloma cells.Conclusions:Cathepsin B has a prominent function in mediating apoptosis potentiated by HDACi and doxorubicin combinations in myeloma. Our results support a molecular model of lysosomal–mitochondrial crosstalk in HDACi- and doxorubicin-potentiated apoptosis through the activation of cathepsin B.

Antioxidant and antiplatelet properties of grape products are thought to be responsible for observed antiatherosclerotic effects. Diverse classes of phenolics are derived from the seed and skin (GSK) of grapes. The relative contributions of the classes of phenolics to observed properties of grape products are unknown. In this paper, GSK fractions were used to examine effects on platelet aggregation, low-density lipoprotein (LDL) oxidation in vitro, and relative binding of phenolics to LDL. GSK was separated into six fractions (fractions 1-6), and primary phenolics were characterized using high-performance liquid chromatography and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Fractions 4, 5, and 6, enriched in polygalloyl polyflavan-3-ols (PGPFs) with 3-6, 4-8, and 6-15 degrees of polymerization, respectively, inhibited platelet aggregation. Fractions 1-3, containing various amounts of oligosaccharides, hydroxycinnamic acids, anthocyanins, flavanols, and low molecular weight PGPFs, significantly increased platelet aggregation. Fractions 4-6 were most effective in binding LDL and inhibiting LDL oxidation. Fractions 5 and 6 exhibited the greatest inhibition of platelet aggregation and LDL oxidation, suggesting that polymeric PGPFs are responsible for the beneficial effects of grape products. Conversely, phenolics in fractions 1-3 may reduce the net biological potency of the grape products and have undesirable effects on cardiovascular disease risk factors.

The compressive creep and recovery of foam earplugs was studied at various applied stresses leading to different fi nal creep strains. Deformation was determined from digital videos of the earplugs via image processing software. Creep could not be modeled by a single exponential in time; creep approximated a power law in time. Nonlinear viscoelasticity was observed: creep compliance depends on stress level. Nevertheless, for strain as high as 24%, recovery follows creep. Recovery does not follow creep at 70% strain. Recovery proceeds to completion given enough time.

Purpose: The objective of this preclinical study is to identify a gene signature that can predict therapeutic responses to vorinostat (SAHA, SuberoylAnilide Hydroxamic Acid), an inhibitor of histone deacetylases (HDACi), which is currently under investigation in multiple myeloma. This is essential for identifying responding patients from nonresponders (intrinsic resistant) to vorinostat who may benefit from alternative treatment. Experimental Design: To determine the antimyeloma effects of vorinostat, bone marrow aspirates from 24 myeloma patients were treated with increasing concentrations of vorinostat (0 − 1 μM) for 72 hrs. The percentage reduction and loss of myeloma cell (CD138+) viability was assessed by Flow Cytometry after staining with FITC conjugated anti-CD138 antibody and 7AAD. CD138+ cells from sensitive (IC50 ≤1 μM) and resistant (IC50 &gt;1 μM groups were enriched to &gt;80% by magnetic separation. Basal gene expression profiles of sensitive and resistant groups were determined using a 48 k Illumina expression array. TM4-MeV software was used to analyze the gene array data to identify genes that were differentially expressed in sensitive and resistant groups, which was confirmed by qRT-PCR and western blotting. Results: Among 24 fresh myeloma samples analyzed, vorinostat achieved IC50 in 10 (41.7%) and IC75 in 5 (20.8%) samples. Nine samples (37.5%) were vorinostat resistant. Non-parametric analysis of gene expression array results identified differential expression of 118 genes (&gt;2x increase in median expression with a P ≤0.05) between sensitive (70 genes) and resistant (48 genes) groups. Interestingly, Ingenuity Pathway Analysis suggested a correlation between differential activation of inflammatory signals and vorinostat sensitivity of myeloma. 17 genes for interferon (IFN) signaling were constitutively expressed in the sensitive group whereas 13 genes related to TNF/IL-6 signaling were predominant in the resistant group. Based upon these results, we hypothesized that IFN-α2b pretreatment would sensitize myeloma cells to vorinostat. As predicted, IFN-α2b and sub-IC50 concentrations of vorinostat combinations synergistically (combination indices of &lt;1) reduced the viability of myeloma cell lines. Conclusions: This study identified 118 genes as potential predictors of patient derived fresh myeloma cell sensitivity to vorinostat. After gene data reduction, a signature of IFN stimulated genes was generated for vorinostat sensitivity and genes related to TNF/IL-6 inflammatory signals for vorinostat resistance. In myeloma cell lines, pretreatment of IFN-α2b augmented antimyeloma effects of vorinostat. Further demonstration of thissynergy on fresh myeloma cells and in mouse xenograft models will provide a rationale for combining these two agents for myeloma therapy. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1684.