bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 1200: BP1 regulates ERα activity in MCF-7 cells
Authors: Berg Patricia E. , Awate Sanket , Kirolikar Saurabh , Schwartz Arnold
Published: June 2012

Introduction. BP1 is a member of the homeobox gene family of transcription factors. Our recent studies have shown that BP1 may play a role in breast cancer cell survival, aggressiveness and metastasis. BP1 protein (pBP1) is expressed in 80% of invasive ductal breast tumors, and is associated with estrogen receptor negativity – 100% of ERα negative (hereafter called ER-) tumors expressed BP1, while 73% of ER positive (ER+) tumors expressed BP1; this difference was statistically significant (p=0.03). Initially most tumors are hormone dependent and are sensitive to antiestrogens. Over time, many tumors progress to hormone-independence. One possible mechanism by which this might occur is reduction of ER protein. Here we present data indicating that high BP1 expression decreases ER protein levels in ER+ cells grown in the absence of serum. Since it is not currently understood what factors may cause ER+ cells to become more ER negative, it is important to determine the role of BP1 in reducing ER protein levels. Results. Our data suggest that MCF-7 ER+ cells engineered to overexpress BP1, when grown in the absence of serum, exhibit decreased ER protein compared with control cells containing an empty vector and grown under the same conditions. This is not a transcriptional effect since there was no change in ER mRNA levels in the presence of high levels of BP1. There was also a decrease in ER immunostaining in cells overexpressing BP1 grown without serum. Decreased ER protein levels correlated with decreased expression of pS2, a known downstream target of ER, demonstrating that there is less functional ER protein in cells overexpressing BP1 when grown in the absence of serum. We speculate that regulation of ER levels by BP1 is post-translational. Several pathways that control ER protein stability are being evaluated in cells grown with or without serum. Phosphorylation of Akt on Ser473, the site that is known to phosphorylate and stabilize ER protein, is being investigated to determine whether BP1 regulates phospho Akt levels. MAPK signaling can result in activation of ER in the absence of estrogen, but we did not see any evidence that BP1 is involved in the MAPK pathway. p300 is known to acetylate and stabilize ER protein; experiments are underway to determine whether BP1 directly regulates p300 expression since there are two potential BP1 binding sites in the p300 gene. Conclusions. We hypothesize that BP1 overexpression leads to reduced ER protein in ER positive cells. This could result in decreased sensitivity to antiestrogens in those cells.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 1200. doi:10.1158/1538-7445.AM2011-1200
Abstract 1202: DCA induces EGFR internalization by a mechanism that is distinct from EGF or UDCA
Authors: Martinez Jesse , Li Qiang
Published: June 2012

Secondary bile acids have long been thought to influence the etiology of colon tumorigenesis however, the mechanism of their action remains unclear. Our previous studies focused on deoxycholic acid (DCA) and ursodeoxycholic acid (UDCA) because they appear to have the opposite effect at the molecular and the biological level. DCA stimulates mitogenic signaling by activating the EGF receptor and can promote tumorigenesis in mouse models, whereas UDCA suppresses EGFR-related mitogenic signaling and has been shown to inhibit colon tumorigenesis in clinical trials. In previous studies we showed that both bile acids act on the cell membrane and this resulted in stimulation of EGFR activity by DCA, but resulted in suppression of receptor signaling by UDCA. In this work, the effect of DCA and UDCA on EGFR internalization in Hct116 cells was investigated using reverse biotinylation. Both DCA and UDCA were found to induce ligand independent internalization of EGFR. However, UDCA treatment resulted in rapid degradation of EGFR whereas DCA caused internalization and stabilization of the receptor in an apparently activated state. To examine this further we pretreated the cells with Methyl-β-cyclodextrin to deplete cholesterol from the plasma membrane, or with chlorpromazine to inhibit endocytosis through clatherin coated pits (CCP). We also suppressed functioning of caveolae or CCPs using caveolin-1 shRNA, or clathrin heavy chain shRNA. We found that EGFR internalization induced by UDCA is cholesterol and caveolin dependent. However, none of these treatments affected the rate of EGFR internalization induced by DCA, suggesting that DCA induced EGFR internalization by a mechanism which is different from that of either EGF or UDCA. This may explain the distinct biological activities exhibited by these two bile acids.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 1202. doi:10.1158/1538-7445.AM2011-1202
Abstract 1208: Elucidating possible functional implications of osteosarcoma risk-associated genetic level alterations in IGF2R
Authors: Piperdi Sajida , Cao Yu , Gorlick Richard
Published: June 2012

To address the need for novel osteosarcoma (OS) treatment regimens with greater efficacy and less toxicity, attention has been focused on developing antibodies that target components of the insulin-like growth factor (IGF) pathway, particularly insulin-like growth factor 1 receptor tyrosine kinase (IGF1R). IGF1R and its two ligands, insulin-like growth factor 1 (IGF1) and insulin-like growth factor 2 (IGF2), are known to be over-expressed in several cancers including OS and have roles in regulating cellular growth and proliferation. Clinical trials of IGF1R-inhibiting antibody therapies in OS, however, have returned mixed results. Studies aimed at elucidating the biologic basis of this differential clinical sensitivity to IGF1R-targeting therapeutic agents are currently underway. Interestingly, recent studies from our lab show that IGF2R is consistently over-expressed, relative to other known transmembrane receptors, on the cell surface, across 4 standard and 10 patient-derived OS cell lines. Coupled with results from concurrent experiments suggesting a lack of IGF1R copy number amplification in the majority of tested patient-derived OS samples and xenograft models, we chose to focus our next set of studies on IGF2R_aiming to characterize significant genetic variations within this gene and any functional implications, thereby elucidating the link, if any, between IGF2R's mutational status and its cell surface expression in OS. Relative quantification studies, done via real-time PCR, demonstrated variable IGF2R gene expression across 27 patient-derived OS samples, 4 xenograft models, and 4 standard cell culture (serum-starved) lines. Using the CaCo-2 cell line as the calibrator, 12 out of 27 patient-derived OS samples showed increased IGF2R gene expression, while none of the xenograft models or the standard OS cell lines did. Ongoing studies will examine the relationship between genetic level alterations in IGF2R and its patterns of expression; common IGF2R SNPs will be genotyped, first in the four available OS xenograft models. Findings will be correlated with known patterns of clinical response/sensitivity to IGF1R-targeted therapy tested on these models. The same SNPs will then be genotyped in the patient-derived OS samples and standard cell culture lines. Depending on the results obtained from these initial studies, further experiments can be designed to sequence/genotype other suspect coding regions on the IGF2R gene that may contain functionally significant mutations.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 1208. doi:10.1158/1538-7445.AM2011-1208
Abstract 1209: Concurrent administration of doxorubicin and lapatinib worsens doxorubicin-induced cardiac dysfunction in mice
Authors: Goukassian David , Sasi Sharath , Lee Juyong , Budiu Daniela , Lawson Christopher , Maysky Michael , Hlatky Lynn , Carrozza Joseph , Morgan James P. , Yan Xinhua
Published: June 2012

Background: Concurrent use of chemotherapy drug doxorubicin (DOX) and Trastuzumab, a monocloncal antibody that blocks HER2, induced cardiac dysfunction in 27% of patients. Clinical trials have shown that the incidence of symptomatic heart failure was much lower (0.3%) in patients sequentially treated with DOX and lapatinib, an EGFR and HER2 tyrosine kinase inhibitor. More studies are necessary to determine the safety of concurrent DOX and lapatinib treatment, which is important for developing more effective cancer therapy. Here, we tested the effect of concurrent DOX and lapatinib administration on cardiac function in mice. Methods: A well-established subacute murine DOX heart failure model was used. 10-12 week old C57BL/6 mice were treated with a single dose of DOX (20 mg/kg, i.p.), or DOX concurrently with lapatinib (100 mg/kg, oral gavage, daily). Survival was analyzed by the Kaplan-Meier method. Cardiac function was monitored by hemodynamic measurements. Results: Ten days after the treatment, survival was significantly lower in DOX+lapatinib vs. DOX mice (13 vs. 0 %, n=7-8 /group, P<0.001). Five to seven days after the treatment, cardiac contractile function was significantly lower in DOX+lapatinib vs. control mice [left ventricular systolic pressure (LVSP): 83 ± 2 vs. 93 ± 2 mmHg, P<0.05; dP/dtmin: 4020 ± 360 vs. 7112 ± 580 mmHg/sec, P<0.05; cardiac output (CO): 1236 ± 266 vs. 2734 ± 209 unit/min, P<0.05, n=5 per group]; however, these indices were maintained in DOX mice at this point (LVSP: 99 ±4 mmHg; dP/dtmin: 7787 ± 965 mmHg/sec; CO: 2315 ± 366 unit/min, P=NS vs. control, n=5-6 per group). Conclusions: These results have shown that concurrent DOX and lapatinib administration exacerbates DOX-induced cardiac dysfunction in mice, suggesting that concurrent use of DOX and lapatanib may not be safe in patients. This study strongly suggests that cardiac function must be closely monitored in patients treated with DOX and HER2 inhibitors.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 1209. doi:10.1158/1538-7445.AM2011-1209
Abstract 1210: Activation of heterogeneous nuclear ribonucleoprotein K (HNRNPK) by ERBB2/ERBB3
Authors: Patel Nirav M. , Xiang Jie , Warren Carmen , Avliyakulov Nurali , Haykinson Michael , Landgraf Ralf
Published: June 2012

ERBB2 (HER2/neu) amplification constitute one of the most prominent oncogenic amplification event in breast cancer, and ERBB2 overexpression is well established as a predominantly proliferation and metastasis favoring signaling input. It is consequently the object of different targeted therapies (e.g. Trastuzumab, Pertuzumab or Lapatinib).

We carried out 2-D difference gel electrophoresis based proteomics studies (DIGE) of early posttranslational protein modifications in MCF7 breast cancer cells in response to ligand induced activation. These studies have identified heterogeneous nuclear ribonucleoprotein K (HNRNPK) as a target for rapid tyrosine phosphorylation after ERBB2/ERBB3 activation by neuregulin β1. Upregulation of protein levels coupled with cytoplasmic accumulation of HNRNPK has been found to be associated with its oncogenic role in several types of cancer, and HNRNPK overexpression enhances the tumorigenicity of breast cancer cells in cell culture models. Previous studies have shown that HNRNPK levels are reduced in breast cancer cells after prolonged treatment with EGFR or ERBB2 directed therapeutic antibodies. However, while molecular mechanistic data exist on HNRNPK from a variety of model systems, we currently lack a coherent mechanistic framework of the crosstalk of ERBB2 and HNRNPK signaling in breast cancer.

Following our DIGE analysis, we found that ligand induced and ERBB2/ERBB3 mediated tyrosine phosphorylation of HNRNPK in MCF7 cells is mediated by members of the SRC kinase family. Following ligand dependent stimulation, activation of HNRNPK coincides with a cytoplasmic relocalization of a relatively small portion of the predominantly nuclear HNRNPK pool. We compared our observations of ligand induced activation with the status of HNRNPK in ERBB2 over expressing breast cancer cell lines in presence or absence of ERBB2 targeted inhibitors. These studies are aimed at elucidating the interplay of HNRNPK and constitutive ERBB2 signaling in breast cancer cells and its role in cellular transformation.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 1210. doi:10.1158/1538-7445.AM2011-1210
Abstract 1213: Neuropeptide Y, adipose tissue and breast cancer
Authors: Ngan Emily , Labus Andrea , Cowen Sarah , Vona-Davis Linda
Published: June 2012

Adipose tissue contributes to obesity-associated risk in breast cancer progression. Recent work has demonstrated the involvement of preadipocytes in promoting the induction of breast tumor cell migration and invasion. Neuropeptide Y (NPY) stimulates proliferation of preadipocytes in vitro by the Y1 receptor. NPY receptors are present in almost all primary breast cancers and in lymph node metastases from ER-positive primary cancers. By contrast, the peptide has been shown to inhibit the invasion of certain tumor cells. However, the relative contribution of adipose and NPY to breast tumor survival remains to be determined. Using the highly metastatic ER-negative human breast cancer cell line MDA-MB-231, we found that NPY significantly inhibited cell proliferation, an effect that was reversed by treatment with the Y1-receptor antagonist BIBP-3226 (P<0.05). Breast tumor cells treated with NPY exhibited changes in cell morphology and demonstrated a two-fold increase in early apoptosis. When breast tumor cells were incubated in the presence of conditioned media harvested from 3T3-L1 preadipocytes, NPY enhanced apoptosis. Significantly more breast tumor cells migrated toward the preadipocytes compared to conditioned media alone (P<0.0001), but less in the presence of NPY. In conclusion, it appears that adipose tissue promotes breast tumor survival and migration, while NPY limits its. It will be of interest to determine whether the tumor migration-promoting activity of preadipocytes varies among breast cancer subtypes, and if so, whether it serves as a predisposing factor for breast cancer progression. In addition, the targeting of NPY-Y1 receptors in breast tumors may have a diagnostic and possibly therapeutic value.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 1213. doi:10.1158/1538-7445.AM2011-1213
Abstract 1240: Characterization of Notch3 in senescence regulation and tumor suppression
Authors: Cui Hang , Zhang Hong
Published: June 2012

Notch signaling has been shown to regulate a broad spectrum of cell fate decisions and differentiation. However, very little is known about the role of Notch signaling in cellular senescence. Here we report that the level of Notch3, a member of Notch transmembrane receptors, is specifically elevated in human fibroblasts during senescence induced by different senescence stimuli. This up-regulation of Notch3 is required for the induction of p21 in senescent cells, whereas adventitious expression of Notch3 in early passage fibroblasts induces senescence accompanied by p21 elevation. Furthermore, we find that Notch3-mediated senescence requires a canonic Notch singling, and deletion of p21 can partially abolish Notch3-induced senescence. The expression of Notch3 is undetectable in a number of human cancer cell lines, and restored expression of Notch3 in these cancer cell lines with undetectable level of Notch3 leads to proliferative arrest. Interestingly, the expression of Notch3 in the luminal subtype of human breast cancer is significantly decreased as compared to other subtypes of breast cancer. More importantly, low level of Notch3 expression in patients with luminal type of breast cancer correlates significantly with poor clinical prognosis. Our results reveal a novel function of Notch3 in senescence regulation and tumor suppression, suggesting that modulation of Notch3 provides a potential therapeutic approach for luminal subtype of breast cancer.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 1240. doi:10.1158/1538-7445.AM2011-1240
Abstract 1246: Role of PKCα and G3BP in stress granule formation
Authors: Winslow Sofia , Kobayashi Tamae , Sunesson Lovisa , Larsson Christer
Published: June 2012

Cells exposed to environmental stress protect themselves from damage by regulation of protein synthesis. Translation of certain proteins is being inhibited at mRNA level in order to influence repair mechanisms. The untranslated mRNAs are assembled into cytoplasmic complexes known as stress granules and will be stalled in this formation until translation is resumed or mRNA is degraded. Apart from mRNA, stress granules contain several proteins with more or less known function for this response. Proteins involved in mRNA stability, e.g. HuR (Hu Protein R), and other RNA-binding proteins are established members in stress granules, whereas heat shock proteins are excluded. Even though many of the constituents of the stress granules are know, the mechanisms behind the formation of stress granules and what role certain proteins have in these complexes are still not fully known.

Ras-GAP binding protein (G3BP) is an mRNA-binding protein that relocates into stress granules upon heat shock and we have data showing that the serine/threonine kinase Protein kinase Cα (PKCα) is recruited to the same complex. We aimed to investigate the role of G3BP and PKCα in stress granule formation and study the interaction between G3BP and PKCα.

Protein interactions between the stress granule proteins PKCα and G3BP, mediated by the C1a-domain of PKCα and the RRM domain of G3BP, were studied in vivo with immunoprecipitation of exogenous constructs as well as in vitro with pull down of pure protein constructs. We further investigated the necessity of PKCα and G3BP in stress granule formation by knocking down the proteins with siRNA. Our data indicate that both proteins are of importance for optimal stress granule formation, but depending on the type of stress, the proteins seem to be of different importance.

Taken together, our results indicate that PKCα have a role in stress granule formation via the RNA-binding protein G3BP.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 1246. doi:10.1158/1538-7445.AM2011-1246
Abstract 1248: Enhanced glutamine metabolism contributes to docetaxel resistance in DU145 prostate cancer cells
Authors: Rajagopalan Kartik N. , Marian Calin O. , Shay Jerry W. , DeBerardinis Ralph J.
Published: June 2012

Chemotherapeutic resistance is one of the major factors contributing to cancer mortality. Although evidence supports a mechanistic link between metabolic enzyme polymorphisms and drug sensitivity, little is known about the metabolic changes tumor cells undergo when treated with a chemotherapeutic agent. Moreover, the metabolic consequences of exposure to these agents may provide essential adaptive functions contributing to chemotherapeutic resistance. Here we used metabolic flux analysis to identify metabolic changes accompanying and potentially accounting for docetaxel resistance in DU145 prostate cancer cells. We focused on the utilization of glucose and glutamine, the two most abundant extracellular nutrients, which together account for the bulk of carbon and nitrogen metabolism in tumor cells. Docetaxel resistant (DOCETR) cells consumed glutamine more avidly and secreted glutamate and ammonia at a greater rate than sensitive parental cells. Surprisingly, contribution of glutamine carbon into the TCA cycle was unchanged in DOCETR cells despite the higher glutamine utilization. Transfer of glutamine carbon into both the intracellular and extracellular glutamate pools, on the other hand, was higher in DOCETR cells, indicating that the DOCETR cells had an increased ability to convert glutamine to glutamate and then to secrete the glutamate. Accordingly, these cells also had increased expression and activity of glutaminase, the major enzyme responsible for glutamine deamidation. Because glutaminase activity does not yield energy unless the resulting glutamate is further oxidized, we hypothesized that this metabolic transition served a non-bioenergetic role, possibly supporting enhanced rates of glutathione synthesis for modification and secretion of docetaxel. Consistent with this idea, DOCETR cells displayed an increase in de novo synthesis of glycine, which is required for the production of glutathione. Importantly, a glutaminase inhibitor re-sensitized DOCETR cells to docetaxel, strongly suggesting that their enhanced glutamine metabolism was involved in resistance to the drug. We speculate that alterations in glutamine metabolism provide a general and targetable mechanism for xenobiotic resistance in cancer cells.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 1248. doi:10.1158/1538-7445.AM2011-1248
Abstract 1270: Metabolic alterations impair breast cancer cell viability following detachment from the extracellular matrix
Authors: Schafer Zachary T.
Published: June 2012

The ability of cancer cells to survive in the absence of normal matrix is critical for tumor progression and metastasis. Normal (non-tumorigenic) cells that lose attachment to extracellular matrix (ECM) undergo caspase-dependent death (known as anoikis), a phenomenon that is frequently defective in cancer cells. However, recent findings reveal that inhibition of anoikis is not sufficient to allow for cell survival in abnormal matrix environments. We have recently discovered that breast cancer cells must rectify detachment-induced metabolic alterations in order to survive in the absence of ECM attachment.

Using MCF-10A cells, we have discovered that cells that are detached from the ECM exhibit a decrease in ATP levels and glucose uptake that is independent of the anoikis program. Interestingly, the treatment of detached cells with antioxidants is sufficient to elevate ATP levels without affecting glucose uptake, suggesting that ROS contribute to the reduction of ATP levels in detached cells. In addition, overexpression of ErbB2 induces a striking rescue of detachment-induced ATP/glucose uptake deficiencies while lowering cellular ROS levels. We found that pentose phosphate pathway (PPP) generated NADPH is essential for ErbB2 to elevate ATP levels and reduce cellular ROS in detached cells. Furthermore, we have discovered that eliminating cellular ROS on its own is sufficient to enhance the viability of matrix-deprived cells. Using a 3-dimensional cell culture system (in which luminal cells lack ECM contact), we have found that antioxidant treatment promotes the filling of the luminal space.

We have now expanded on these studies and found a role for these detachment-induced metabolic alterations in inflammatory breast cancer cells and have discovered an Akt-independent signaling pathway downstream of oncogenic Ras that also promotes detachment-induced viability. Our current studies are also focused on understanding the role of ROS in regulating ATP generation by fatty acid oxidation. Furthermore, we are examining the role of the tumor microenvironment in the regulation of caspase activation and metabolism in detached epithelial cells. These studies could lead to the identification of novel molecular mechanisms that could be targeted for the selective elimination of ECM-detached cancerous cells.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 1270. doi:10.1158/1538-7445.AM2011-1270
Abstract 1271: Human non small cell lung cancer tissue has enhanced expression of pyruvate carboxylase, but not glutaminase
Authors: Fox Matthew P. , Bousamra Michael , Slone Stephen P. , Lane Andrew N. , Fan Teresa W-M
Published: June 2012

Altered cellular metabolism in tumors is well established, particularly an increased rate of aerobic glycolysis [1]. However, increased glycolysis alone is insufficient to sustain the enhanced cell growth and anabolic metabolism characteristic of cancer. Another key source of these precursors is the citric acid cycle (CAC). Removal of CAC intermediates for anabolism requires replenishment by other sources; these anaplerotic reactions are vital to cancer development. The two major pathways of anaplerosis are glutaminolyis (deamidation and transamination of glutamine to 2-oxoglutarate) [2] and carboxylation of pyruvate to oxaloacetate (OAA), catalyzed by pyruvate carboxylase (PCB) [2].

We have coupled 13C-labeled glucose tracer with stable isotope resolved metabolomics (SIRM), gene microarray, and western blotting to track the anaplerotic PCB pathway in human lung cancer patients. The resected cancer tissue showed increased flux through the PCB pathway, along with increased transcription of the PCB gene and PCB protein expression compared with the adjacent benign lung tissue [3]. We have extended these findings to 50 paired tissue samples, and have correlated them with histological and clinical data. The protein expression of PCB was on average ten-fold higher in the tumor than in the benign lung tissue (p=0.00001, paired t-test). The normalized protein expression correlated with the fraction of the tumor that was identified as cancer cells, indicating that the increased expression was from the cancer cells rather than other lung cell types. Glutaminase was active in the lung tissue, but its expression was not different from, or lower in the tumors than in the benign lung tissue.

These data indicate that in NSCLC, PCB is important in anaplerosis and tumor metabolism. The balance between glycolysis and the choice of different anaplerotic pathways may depend on the tissue types.

References

1. Gillies, R.J. and R.A. Gatenby, Adaptive landscapes and emergent phenotypes: why do cancers have high glycolysis? Journal of Bioenergetics and Biomembranes, 2007. 39(3): p. 251-257.

2. Portais, J.C., P. Voisin, M. Merle, and P. Canioni, Glucose and glutamine metabolism in C6 glioma cells studied by carbon 13 NMR. Biochimie, 1996. 78(3): p. 155-164.

3. Fan, T.W., A.N. Lane, R.M. Higashi, M.A. Farag, H. Gao, M. Bousamra, and D.M. Miller, Altered Regulation of Metabolic Pathways in Human Lung Cancer Discerned by 13C Stable Isotope-Resolved Metabolomics (SIRM)) Molecular Cancer 2009. 8 p. 41.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 1271. doi:10.1158/1538-7445.AM2011-1271
Abstract 1273: Metabolic networks and the role of LDHB in breast cancer
Authors: Dennison Jennifer B. , Molina Jennifer R. , Guo Huifang , Mills Gordon B.
Published: June 2012

Gene expression data of breast cancer cell lines and patient tumors reveal several distinct subtypes that demonstrate different metabolic phenotypes. Our goal was to determine what metabolism genes contribute to the metabolic phenotypes. We hypothesized that dichotomous expression of metabolism genes would identify key drivers of cell metabolism. To select candidate genes, we completed a bimodal analysis using microarray data from 59 breast cancer cell lines. To generate a metabolic network, dichotomous genes were selected from known or probable metabolic networks including electron transport, TCA cycle, nutrient transport, pentose phosphate shunt, energy requiring pathways, and glycolysis. Two groups of dichotomously expressed genes emerged from this analysis: TCA cycle anaplerotic genes (including PFKP, GLS) and cataplerotic/biosynthetic genes (including FASN, GLUL, and FBP1). The gene with the highest bimodal index was LDHB that encodes lactate dehydrogenase B. For breast cancer cell lines, LDHB mRNA and protein were most highly expressed in ER-, glycolytic cell lines. LDHB is reported by others to be part of a “MYC signature,” and consistent with this hypothesis, for ER- cell lines, LDHB mRNA levels were highly associated with MYC and glutaminase, a metabolic down-stream target of MYC. For patient tumors, LDHB mRNA expression was also bimodal with the highest expression in basal-like cancers. Elevated expression of LDHB mRNA predicted worse clinical outcomes for patients with Her2 positive and triple negative tumors. Compared to normal-like breast tissue from patients, LDHB mRNA expression was elevated in triple negative tumors. We conclude that LDHB may be a target of MYC and contribute to the glycolytic phenotype of triple-negative tumors.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 1273. doi:10.1158/1538-7445.AM2011-1273
Abstract 1279: Loss of PTEN expression in patients treated with PI3K/AKT/mTOR signaling pathway inhibitors
Authors: Janku Filip , Garrido-Laguna Ignacio , Tsimberidou Apostolia M. , Naing Aung , Fu Siqing , Falchook Gerald S. , Abraham Susan C. , Hong David S. , Kurzrock Razelle
Published: June 2012

Background: Loss of PTEN function results in increased PI3K/AKT/mTOR signaling and may predict sensitivity to drugs targeting the PI3K/AKT/mTOR pathway.

Methods: Archival tumor samples from patients (N = 202) with diverse cancers referred to the Clinical Center for Targeted Therapy from October 2009 were tested for cytoplasmatic expression of PTEN on immunohistochemistry. Whenever possible, tumor tissue was also analyzed for PIK3CA, RAS (K-, N-), and BRAF mutations using PCR-based DNA sequencing. Consecutive patients with loss of PTEN expression and any tumor type were treated whenever possible with agents targeting the PI3K/AKT/mTOR signaling pathway.

Results: Overall, 49 (24%) of 202 patients had loss of PTEN expression. In specific tumor types with a minimum of five patients tested, the loss of PTEN expression was most frequent in squamous cell cervical (60%, 3/5 patients), non-small-cell lung (50%, 4/8), renal (50%, 3/6), uterine (41%, 7/17), gastroesophageal junction/gastric (38%, 3/8), breast cancers (25%, 2/8), melanomas (22%, 6/27), and colorectal cancers (20%, 6/30). Tumors with PTEN loss had frequencies of simultaneous mutations in PIK3CA, RAS (K-, N-), BRAF that were similar to patients with PTEN expression. Of the 49 patients with PTEN loss, 29 (median number of prior therapies, 3) were treated on a protocol that included a PI3K/AKT/mTOR pathway inhibitor. Six of these 29 patients (20.5%) achieved a partial response (PR) (2 uterine cancers, 1 squamous cell cervical cancer; 1 squamous cell head and neck cancer; 1 melanoma; 1 renal cancer) and 8 (27.5%) had stable disease (SD) for >/ = 4 months (total SD>/ = 4 months + PR = 48%). These 29 treated patients had a median progression-free survival of 4.3 months (95% CI, 3.4-5.2).

Conclusion: Loss of PTEN expression was found in 24% of patients with various solid tumors. Fourteen of 29 heavily-pretreated patients (48%) had a PR or SD >/ = 4 months, when treated with a PI3K/AKT/mTOR axis inhibitor, suggesting that matching patients with these inhibitors based on PTEN loss merits further exploration.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 1279. doi:10.1158/1538-7445.AM2011-1279
Abstract 1282: Phase I evaluation of STA-1474, a pro-drug of the novel HSP90 inhibitor STA-9090, in dogs with spontaneous cancer
Authors: London Cheryl A. , Bear Misty D. , McCleese Jennifer , Foley Kevin P. , Paalangara Reji , Inoue Takayo , Ying Weiwen , Barsoum James
Published: June 2012

The novel water soluble compound STA-1474 is metabolized to STA-9090, a potent HSP90 inhibitor previously shown to kill canine tumor cell lines in vitro and inhibit tumor growth in the setting of murine xenografts. The purpose of the following study was to extend these observations and investigate the safety and efficacy of STA-1474 in dogs with spontaneous tumors. This was a Phase 1 trial in which dogs with spontaneous tumors received STA-1474 under one of three different dosing schemes. Pharmacokinetics, toxicities, biomarker changes, and tumor responses were assessed. Twenty-five dogs with a variety of cancers were enrolled. Toxicities were primarily gastrointestinal in nature consisting of diarrhea, vomiting, inappetence and lethargy. Upregulation of HSP70 protein expression was noted in both tumor specimens and PBMCs within 7 hours following drug administration. Measurable objective responses were observed in dogs with malignant mast cell disease (n=3), osteosarcoma (n=1), melanoma (n=1) and thyroid carcinoma (n=1), for a response rate of 24% (6/25). Stable disease (>10 weeks) was seen in 3 dogs, for a resultant overall biological activity of 36% (9/25). This study provides evidence that STA-1474 exhibits biologic activity in a relevant large animal model of cancer. Given the similarities of canine and human cancers with respect to tumor biology and HSP90 activation, it is likely that STA-1474 and STA-9090 will demonstrate comparable anti-cancer activity in human patients.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 1282. doi:10.1158/1538-7445.AM2011-1282
Abstract 1286: Pharmacodynamics of oral curcumin in plasma and rectal mucosa in a Phase IIa trial
Authors: Kakarala Madhuri , Carroll Robert E. , Turgeon Kim , Tuck Melissa , Benya Richard V. , Meyskens Frank , Brenner Dean
Published: June 2012

Background: Curcumin, a dietary polyphenol derivative of turmeric, has potent cancer reductive activity in in vivo colon carcinogenesis models. We administered curcumin at doses of 2 g or 4 g to separate groups of 20 healthy human smokers with > 8 aberrant crypt foci (ACF). The 2 g dose showed no ACF reduction while the 4 g dose showed a 46% reduction (p<0.005) We analyzed native curcumin and its conjutes in matched plasma and rectal mucosa biopsy sample from 21 participants at 2g and 18 participants at 4g.

Methods: Curcuminoid products were extracted from homogenized biopsy tissue and ultacentrifuged plasma and evaporated under argon. The separation was performed on a Symmetry® C18 column. The mobile phase used under gradient conditions was 25% acetonitrile with 74.9% containing 0.1% acetic acid (25:74.9:0.1; v/v/v; A) and 100% acetonitrile containing 0.1% acetic acid (99.9:0.1; v/v; B) The flow rate was 0.3 mL/min and injection volume for all samples was 10 µL. The lower limit of detection for curcumin from human plasma was 5 ng/mL and from human colonic mucosa was 50 ng/5mg tissue.

Results: See Table below (summarized by pre and post treatment dose for plasma and mucosal concentrations)

Conclusions: Native curcumin is not detectable in the majority of biopsy and plasma samples. Conjugated curcumin is detectable in all plasma samples and the majority of mucosal biopsies with a significant increase in plasma concentrations at 4g. We postulate the conjugates detected in the rectal mucosa are delivered systemically from absorption and conjugation higher in the gastrointestinal tract and may have biologic activity.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 1286. doi:10.1158/1538-7445.AM2011-1286
Abstract 1316: Overactivation of AKT promotes hormone-independent mammary tumors
Authors: Riggio Marina , Polo Laura , Blaustein Matias , Colman-Lerner Alejandro , Lanari Claudia , Novaro Virginia
Published: June 2012

Using a mouse mammary tumor model induced by medroxyprogesterone acetate (MPA) that transits through different stages of hormone dependence, we have previously reported that the activation of the PI3K/AKT pathway is critical for the growth of hormone-independent (HI) mammary tumors, but not for the growth of a hormone-dependent (HD) tumor variant.

The main aim of this work was to explore whether the activation of the PI3K/AKT pathway per se is responsible for the transition from a HD to a HI tumor phenotype. To answer this question we infected primary cultures of epithelial cells obtained from HD tumors with a retrovirus that directs the expression of a constitutively active form of AKT1 (myristoylated AKT1, myrAKT1), or with the empty vector as control. We inoculated 103 cells in nude mice (n = 6). MyrAKT1 expressing HD-derived cells were able to form mammary tumors even in the absence of MPA, that is, they behaved as HI cells. These tumors were highly differentiated and displayed a ductal phenotype with a pattern of expression of cytokeratin 8 and laminin-1 typical of HI tumors. Ligand-independent phosphorylation of progesterone receptor (PR) in Ser 190 was also increased in myrAKT1 tumors supporting our hypothesis that overactivation of AKT is directly involved in the acquisition of hormone independence. Furthermore, comparing myrAKT tumors with uninfected HD tumors revealed that overactivation of AKT did not increase the incidence of lung metastasis, indicating that AKT1 is involved specifically with tumor differentiation and growth rather than with tumor cell invasiveness.

In vitro, primary cultures of mammary tumor cells modified to express myrAKT1 showed similar levels of proliferation determined by Ki67 and H3-tymidine incorporation as compared to control (cells infected with the empty vector), suggesting that the in vivo tumorigenic effect of myrAKT1 cells described above might require cell-cell or cell-matrix interactions absent in vitro. Interestingly, we found that conditioned medium from myrAKT1 tumor cells increase endogenous AKT1 activity when tested in untransfected cells. Moreover, conditioned medium from HI carcinoma associated fibroblasts (CAF-HI) increased the level of activation of the PI3K/AKT pathway in epithelial cells. Altogether, these results indicate that paracrine signals derived from the tumor cells and/or its microenvironment participate in the activation of the PI3K/AKT pathway, ultimately leading to tissue differentiation and ligand-independent mammary tumor growth. Thus, the PI3K/AKT pathway might be a key therapeutic target to prevent progression to autonomous and endocrine resistant breast tumors.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 1316. doi:10.1158/1538-7445.AM2011-1316
Abstract 132: miR-133a as a tumor suppressive microRNA targeting multiple oncogenes in head neck squamous cell carcinoma
Authors: Nohata Nijiro , Hanazawa Toyoyuki , Kikkawa Naoko , Mutallip Muradil , Fuse Miki , Chiyomaru Takeshi , Kawakami Kazumori , Enokida Hideki , Nakagawa Masayuki , Okamato Yoshitaka , Seki Naohiko
Published: June 2012

Head and neck squamous cell carcinomas (HNSCC) represent 6% of all cancers. Despite of considerable advances in surgery, radiotherapy and chemotherapy, the overall 5-year survival rate for patients is less than 40% in advanced stage. The understanding of the new molecular pathways of HNSCC carcinogenesis would be helpful in improving diagnosis and therapy of the disease.

MicroRNA(miRNA) are endogenous short non-coding RNA molecules, which regulate gene expression by repressing translation or cleaving RNA transcripts in a sequence-specific manner. Growing evidence suggests that miRNAs are aberrantly expressed in many human cancers, and that they play significant roles in carcinogenesis and cancer progression. Bioinformatic prediction indicates that miRNAs regulate more than 30% of the protein coding genes. The study of the tumor suppressive miRNAs and their target genes search is important for understanding of the HNSCC carcinogenesis.

Based on our miRNA expression signature of HNSCC, miR-133a is one of the down-regulated miRNA and this finding suggests that miR-133a is a candidate of tumor suppressor. Gain-of-function analysis revealed that miR-133a transfectant inhibited cell proliferation and cell invasion in cancer cells. For target genes search of miR-133a in cancer cells, we performed genome-wide protein coding expression analysis. Among the expression study, several candidate genes were identified, such as, fascin homolog 1 (FSCN1), glutathione S-transferase P1 (GSTP1) and caveolin-1 (CAV1). Silencing of these genes showed that significant inhibition of cell growth and invasion were demonstrated in HNSCC cancer cells.

Tumor suppressive miR-133a and its target oncogenes may provide new insights into the mechanisms in cancer. Our findings have therapeutic implications and may be exploited for future HNSCC treatments.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 132. doi:10.1158/1538-7445.AM2011-132
Abstract 1321: Estrogen-like effects of cadmium in male mice and the involvement of MAPKs pathway
Authors: Ali Imran , Penttinen-Damdimopoulou Pauliina E. , Mäkelä Sari I. , Berglund Marika , Stenius Ulla , Adamsson Annika , Åkesson Agneta , Håkansson Helen , Halldin Krister
Published: June 2012

Cadmium is a ubiquitous toxicant of environmental concern, classified as a category 1 human carcinogen. Clear estrogen-like effects of cadmium have been reported in ovariectomized rats after a single dose. Recent epidemiological findings might suggest increased risk of hormone-related cancers such as cancer of the endometrium and breast. However, the specific molecular mechanism of action is unknown. Recently, we have shown that estrogen-like effects of cadmium in female mice do not appear to be mediated via the classical estrogen receptor transcriptional pathway. However, some estrogen like effects, possibly mediated via the non-classical estrogen signaling pathway were observed. The aim of the present study was to investigate the estrogen-like effects of cadmium in male mice. ERE-luc male mice were injected subcutaneously with CdCl2 at 0.5, 5, 50 or 500 µg/kg b.w. or with 17α-ethinylestradiol (EE2) on three consecutive days. Testicular weights and histology, body and organ weight, Cd-tissue retention, activation of MAPK pathways and ERE dependent luciferase expression were investigated. Body weight and relative liver and kidney weights were not altered in any of the CdCl2 or EE2 treated animals as compared to the control. Relative testis weights were significantly decreased in 0.5 and 50µg CdCl2/kg b.w. treated animals as compared to control. Testicular histology analysis showed no significant changes in the tubulus diameter and epithelial thickness at stage VII, however some apoptotic cells were observed in mice treated with CdCl2. No significant alterations in ERE mediated luciferase activity were detected in any of the CdCl2 treated groups. Phosphorylation of Mdm2 was significantly increased at relatively low-dose of CdCl2 (5µg/kg b.w.), whereas no significant changes in phosphorylation of Akt were observed in CdCl2 or EE2 treated animals. Phosphorylation of Erk was found to be significantly increased after exposure to 0.5, 5 and 50µg of CdCl2/kg b.w. as compared to control. Gene expression of c-myc, c-fos, c-jun and p53 appeared to be decreased at relatively low dose of CdCl2 (5µg/kg b.w). No significant changes were observed in the expression of HSP32, p38, SP1 or ER-alpha after CdCl2 exposure. In conclusion the results suggest the involvement of MAPKs signaling pathways in cadmium induced effects in vivo after short term exposure at the doses investigated.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 1321. doi:10.1158/1538-7445.AM2011-1321
Abstract 1331: Green tea catechin suppression of carcinogenesis and cell proliferation induced by environmental carcinogens 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone and benzo[a]pyrene
Authors: Rathore Kusum , Wang Hwa-Chain R.
Published: June 2012

In this study we aim to identify the role of green tea catechins (GTCs) in early prevention of breast cell carcinogenesis induced chronically by environmental carcinogens. Most sporadic breast cancers are attributable to long-term exposure to environmental factors through a multi-year, multi-step, and multi-path disease process involving cumulative genetic and epigenetic alterations in progressive breast cell carcinogenesis. Epidemiologic and experimental studies have shown that GTCs may intervene with breast cancer development. However, the mechanisms for GTC prevention of cellular carcinogenesis induced by chronic exposure to environmental carcinogens remain to be elucidated. To study the activity of GTC components in suppression of cellular carcinogenesis, we used our cellular carcinogenesis model that mimics chronic breast cell carcinogenesis induced by cumulative exposures to low doses of the environmental carcinogens 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) and benzo[a]pyrene (B[a]P). We detected that the four major GTC components epicatechin (EC), epicatechin-3-gallate (ECG), epigallocatechin (EGC), and epigallocatechin-3-gallate (EGCG) at non-cytotoxic levels were able to suppress NNK- and B[a]P-induced cellular carcinogenesis, as measured by suppression of the acquired cancer-associated properties of reduced dependence on growth factors, anchorage-independent growth, and increased cell mobility. We also detected that ECG was more effective than EC, EGC, and EGCG in suppression of cellular carcinogenesis. Investigating the mechanisms for GTCs in counteracting carcinogenic activity of NNK and B[a]P, we detected that all the catechins were able to suppress carcinogen-induced reactive oxygen species (ROS), resulting in suppressing ROS-induced ERK pathway activation, cell proliferation, DNA damage, and p53 expression. Our cellular model provided a new platform to identify dietary components, at non-cytotoxic levels, capable of effectively intervening in chronic breast cell carcinogenesis induced by cumulative exposures to low doses of environmental carcinogens.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 1331. doi:10.1158/1538-7445.AM2011-1331