bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 87: Micropapillary breast carcinoma is characterized by deregulation of genes involved in cell division control
Authors: Gruel Nadege , Benhamo Vanessa , Popova Tatiana , Gauthier Arnaud , Cascone Ilaria , Arnould Laurent , Fréneaux Paul , Cedenot Aurelie , Mariani Odette , Bhalshankar Jaydutt , Pierron Gaëlle , de Cremoux Patricia , Reyal Fabien , Alran Severine , Cottu Paul , Fourquet Alain , Sastre Xavier , Stern Marc-Henri , Camonis Jacques , Delattre Olivier , Vincent-Salomon Anne
Published: August 2012

This study provides insight into the biological specificities of invasive micropapillary carcinoma of the breast (IMPC), an entity characterized by cell polarity inversion and frequent lymphovascular invasion and axillary lymph node metastasis compared to invasive ductal carcinoma (IDC). Morphological review was combined with copy number analyses, genotyping (SNP6.0 Affymetrix), TP53 and PIK3CA sequencing and transcriptomic analysis in a series of 39 pure IMPC and the results were compared to those of 19 IDC with positive estrogen receptors, and positive axillary lymph node and lymphovascular invasion (ER+, N+, LVI+). The presence of numerous bi-nucleated cells was identified as a morphological pattern of IMPC. This specific trait was underlined by deregulation of the expression of genes involved in cell division. IMPC and IDC exhibit common genomic alterations including 8p-, 8q+, 16q-, 17p13- and 22q- and mutations of PIK3CA (10% for IMPC and 11% for IDC) and TP53 (13% in IMPC vs 33% in IDC). In contrast, IMPC were specifically characterized by frequent 17q23.2-q24.1 gains (54%), chromosomes 17q 23.1 (26%), 17q12 (22%), 8q22.1 (21%) amplifications and 6q16.1-q22.31 losses (43%). Within the IMPC group, unsupervised analysis of genomic data distinguished two distinct subsets: one subset (16 IMPC) exhibited a significant increase in 16p gains associated with near-diploid cells and the second subset (19 IMPC) characterized by a high frequency of 8q, 17q and 20q amplifications associated with near-tetraploid cells. This analysis showed that IMPC constitutes a distinct entity from ER+ N+ LVI+ IDC with, in particular, high frequencies of bi-nucleated cells, 17q gains and amplifications associated with 6q losses of heterozygosity. This study also showed that IMPC comprises two genomic subsets that may suggest the existence of different oncogenic mechanisms giving rise to the same morphological entity.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 87. doi:1538-7445.AM2012-87
Abstract 870: Synergistic antitumor activity of AKT inhibitor MK2206 and FUS1-nanoparticles in LKB1 mutant NSCLC
Authors: Meng Jieru , Lara-Guerra Humberto , Ji Lin , Roth Jack A.
Published: August 2012

FUS1, a novel tumor suppressor gene in the human chromosome 3p21.3 region, is deleted in many cancers. A phase I clinical trial assessing FUS1-mediated molecular therapy has reported antitumor activity in lung cancer patients. Previous studies showed that FUS1 regulates the activation of multiple oncogenic kinases. MK2206 is a highly selective non-ATP-competitive allosteric inhibitor of AKT currently being evaluated in early-phase clinical trials for treatment of patients with lung cancer. In this study, we evaluated the combined effects of the tumor suppressor gene FUS1 and MK2206 on tumor cell growth and apoptosis induction in NSCLC cells and explored the molecular mechanism of their mutual action. We found that exogenous expression of FUS1 sensitized the response of NSCLC cells to MK2206, resulting in a marked increase in growth suppression and apoptosis in LKB1-mutant NSCLC cells. However, FUS1 had no effect on the response of LKB1-wild-type NSCLC cells to MK2206. Systemic treatment with a combination of FUS1-nanoparticles and MK2206 in an LKB1 mutant H322 lung cancer subcutaneous xenograft mouse model enhanced the therapeutic efficacy of MK2206. The mice receiving the combination of MK2206 and FUS1-nanoparticles showed a significantly reduced mean tumor volume (364±164 mm3) compared with mice receiving empty vector/MK2206 (728±101 mm3), MK2206 alone (926±250 mm3), FUS1 alone (1171±294 mm3), or empty vector (2405±737 mm3) by day 21 (P<0.01 for all three comparisons). Our results show that FUS1 may play a role in modulating the sensitivity of lung cancer cells to AKT inhibition, and suggests that a combination of FUS1-nanoparticles and MK2206 may be an effective treatment strategy for LKB1 mutant human lung cancers.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 870. doi:1538-7445.AM2012-870
Abstract 877: Identification of novel genes critical to survival of MPNST cells via medium throughput screening using lentiviral shRNA
Authors: Patel Ami , Ratner Nancy
Published: August 2012

Malignant peripheral nerve sheath tumor (MPNST) is a soft tissue sarcoma that is highly invasive and eventually lethal. About 50% of MPNSTs have mutation and/or loss of the NF1 gene, while the rest are spontaneous. Many MPNST also show mutations in p53 and/or homozygous deletion of CDKN2. In an effort to identify novel genes that play key roles n MPNST tumorigenesis, we performed a genome wide micro-array analysis using human neurofibroma and MPNST (Miller et al., 2009). This analysis identified 130 genes that are up-regulated >3 fold in MPNSTs as compared to normal human Schwann cells. Over expression of these genes in tumors as compared to normal cells suggested that some might be critical for survival of MPNST cells. This hypothesis was directly tested by studying effects on survival of MPNST cells in vitro post down regulation of the 130 genes using lentiviral short hairpin (sh) RNA. For each shRNA experiment a sh non-targeting lentivirus was used as a negative control and shSOX9, a construct previously shown to kill MPNST cells in vitro, was used as a positive control for an effect on cell survival. Screening was performed sequentially allowing for selection of genes with significant effects on survival. In screen I, T265 MPNST cells were exposed to each shRNA virus. In screen II, shRNAs were tested for effects on adenocarcinoma cells (A549) vs T265 cells. These two round of screens identified 10/130 genes specific for survival of T265 cells. Screen III was performed on four different MPNST cell lines, including T265 (NF1-/-), 8814 (NF1-/-), S462TY (NF1-/-) and SSTS26T (sporadic MPNST wild-type for NF1), to identify shRNA's with similar or different effects on cell survival in the presence or absence of wild-type NF1 gene. No significant difference in survival was observed for NF null MPNST cells vs sporadic MPNST cell line for any gene. This approach facilitates a streamlined pathway from genome wide gene expression analysis to identification of novel genes critical to survival of cancer cells in vitro. Future studies will be directed toward testing the identified genes for roles in tumor formation and growth, and as potential MPNST therapeutic targets.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 877. doi:1538-7445.AM2012-877
Abstract 878: In vitro selection of metastatic breast cancer cells based on their adaptability
Authors: Singh Balraj , Raythatha Milan R. , Cady Amanda M. , Madan Simran , Tai Karen , Irving LaTashia R. , Lucci Anthony
Published: August 2012

The success of cancer depends on ongoing generation of genetic and epigenetic heterogeneity in cancer cells, and the selection of cells that are most adaptable at surviving numerous obstacles in the body. Current approaches of personalized therapy, mostly designed to inhibit cell proliferative function of a single protein, may not succeed unless we target adaptability of cancer cells as well. We reported recently that it is possible to isolate highly metastatic rare cancer cells (< 0.01% in SUM149 inflammatory breast cancer cell line) based on their adaptability to survive without glutamine in culture medium. These studies also provided evidence of a high COX-2 expression in such Gln-independent cells and in subpopulations that survived lack of serum and attachment. To determine the usefulness of our new function-based selections, we compared different COX-2 overexpressing subpopulations with the parental SUM149 cell line for their adaptability to survive lack of Gln- 1) COX-2 overexpressing cells that survive lack of serum and attachment (designated SWS), and 2) a pre-existing COX-2 overexpressing clone (clone 5) isolated by picking individual colonies. We found that the SWS variants yielded significantly more colonies (2-3 fold) than the parental cell line upon Gln withdrawal. In contrast, clone 5 failed to yield any Gln-ind colony. Further investigation into the adaptability of Gln-ind cells revealed that they are better able to survive exposure to hypoxia than the parental cell line. We obtained similar results with hypoxia caused by cell culture in 0.5% oxygen or with hypoxia caused by exposure to cobalt chloride. These results support a model in which rare cells that drive metastasis are proposed to be adaptable in multiple ways. Our studies suggest that the function-based selection of adaptable cancer cells is able to select unique cancer cells from a heterogeneous population that may not be selectable on the basis of specific biomarkers. We conclude that it is feasible to isolate rare metastatic breast cancer cells with a function-based robust selection of adaptable metabolic state. In vitro assays utilizing such adaptable and metastatic cancer cells will likely aid anti-cancer drug discovery efforts.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 878. doi:1538-7445.AM2012-878
Abstract 881: Leveraging the molecular heterogeneity of patient-derived tumor samples to simulate clinical trial settings and model combination treatments
Authors: Streiner Nicole , Praveen Kesavan Nair , Ruiz-Larroya Tatiana , Vo Martin , Murali Bhavya , Hoffmaster Steve , Broudy Thomas , Mirsaidi Cyrus , Anderes Kenna
Published: August 2012

Combination therapy, with rare exception, is a requirement for successfully treating cancer patients. Advances in genetic characterization coupled with a growing understanding of tumor heterogeneity are poised to revolutionize future strategies for combination treatments. Historically, working out the best combinations has been challenging and largely through iterative cycles of clinical trial and error due to gross limitations of preclinical models to accurately predict activity. Current strategies for developing new anticancer drugs rely heavily on preclinical testing in cancer cell lines and their derived in vivo xenograft models. These models are fraught with significant limitations including highly passaged cancer cell lines grown on plastic that ignores the microenvironment and tempered representation of the complex heterogeneity of cancer. Tumor cell microenvironment has significant impact on growth kinetics, cell signaling and response to drug treatments. 3D models attempt to recapitulate elements of the microenvironment, are more biologically relevant models compared to 2D models and have gained preference among cancer researchers and drug developers. The purpose of this study is to investigate the utility of molecularly characterized patient derived lung tumor cells (PTCs) for steering decisions for effective combination treatments in the clinical setting. We have established preclinical lung cancer models using PTCs grown in a 3D culture system. Here we present a retrospective study in lung PTCs evaluating single agents and combinations of molecularly targeted as well as cytotoxic agents including erlotinib, crizotinib, etoposide, cisplatin, carboplatin, gemcitabine, paclitaxel, vinorelbine, topotecan and irinotecan. We utilized a range of methods (PCR, FISH, IF, WB) to determine the genetic and molecular features of the PTCs prior to performing drug treatments. We used high content imaging to evaluate subpopulations within PTCs, colony morphology and proliferative endpoints. Our results identified responder and non-responder populations and emphasize the need to base combination treatment strategies on subpopulation analysis of the tumor. Patient-derived tumor cell models grown in 3D culture conditions coupled with molecular characterization are essential for conducting hypothesis driven studies. This approach offers an informed starting point for subsequent in vivo studies from which data can guide personalized medicine decisions toward true translation in the clinic.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 881. doi:1538-7445.AM2012-881
Abstract 886: Developing a new concept for specific targeting of cancer cells
Authors: Kosak Ken M.
Published: August 2012

The purpose of this work is to demonstrate the feasibility for 100% specific killing of cancer cells and virtually zero killing of normal cells. This is an obvious goal that seems to have been lost in most of the current targeting strategies for treating cancer. For instance, one well-known strategy employs drugs that kill or inhibit cancer cells through their generally higher metabolic rate and uptake of nutrients. A second strategy uses drug conjugates and/or carrier systems that target cell surface receptors or antigens. Another strategy now gaining rapid acceptance is using cancer genomics and/or proteomics to more “specifically” inhibit various up-regulated metabolic targets in cancer cells. The use of inhibitors and/or the current limitations of toxic drugs result in incomplete killing of the cancer, which frequently results in resistance. Another purpose of this work is to redirect some of the massive resources of industry and academia back to the harder task of specifically killing cancer instead of just inhibiting it. If all cancer cells are killed during treatment, there is no opportunity for resistant cells to grow back. Therefore, the ideal goal is to produce a drug and/or drug delivery system that is virtually 100% specific for killing cancer. This 100% specificity must be based on properties that only cancer cells possess. This eliminates normal cell surface receptors or metabolic pathways that are simply up-regulated or down-regulated compared to normal cells. Cancer is caused by one or more mutations in DNA. Therefore, all cancers have at least one or more mutations that are not found in normal cells. These unique mutations are the truly specific targets that should be used for killing cancer cells. The methods in this work identify mutations inside live cancer cells through specific binding to mutated DNA, (or the resulting mutated proteins). By employing a unique delivery system, a highly toxic compound is released into the cancer cell only when specific binding occurs. This feasibility study will show that nearly 100% of cancer cells can be killed through cancer-specific, intracellular targets while normal cells are not.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 886. doi:1538-7445.AM2012-886
Abstract 888: In vitro selection of prostate cancer cell-specific molecular recognition elements
Authors: Williams Ryan M. , Nayeem Sara , Sooter Letha J.
Published: August 2012

Among males in the United States, prostate cancer is the most-diagnosed cancer and is the second leading cause of cancer-related deaths. Current detection and therapeutic methods are not specific for the disease. The current standard in detection, prostate specific antigen (PSA) levels in the blood, was recently given a “D” grade by the U.S. Preventative Services Task Force. To address this problem, molecular recognition elements (MREs) that bind with high affinity and specificity to a molecule displayed on the surface of prostate cancer cells but not benign prostate cells are being developed. MREs are obtained through the in vitro selection process, which is the iterative enrichment of a large pool of random biomolecules for those that bind to a target of interest but not closely related targets. Seven rounds of in vitro selection have been completed, enriching a yeast-displayed single-chain variable fragment (scFv) antibody library with an initial diversity of 10^9 molecules. First, three rounds of biopanning were performed. In the positive panning selections, yeast-displayed scFv molecules were incubated with the LNCaP prostate cancer cell line. Those that bound to the LNCaP cells were amplified and subjected to a negative panning selection, in which the scFv's were incubated with benign prostate cell lines. These cell lines represented high grade prostatic intraepithelial neoplasia, benign prostate hyperplasia, and normal prostate cells. Those that did not bind to the benign cells were amplified. Then, four rounds of fluorescent activated cell sorting (FACS) were completed with increasing stringency. Binding of selected scFv MREs is being characterized. This work will produce a prostate cancer cell-specific MRE useful in specific detection and therapeutic targeting of prostate cancer.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 888. doi:1538-7445.AM2012-888
Abstract 892: Angiotensin II /angiotensin II type I receptor (AGTR1) promotes cell growth in epithelial ovarian cancer
Authors: Lee Jeong-Won , Park Young-Ae , Choi Chel Hun , Lee Yoo-Young , Choi Jung-Joo , Kim Byoung-Gie , Bae Duk-Soo , Jeon Hye-Kyung , Kim Ha-Jeong , Cho Young Jae , Ryu Jee-Yun
Published: August 2012

Background: Angiotensin and its receptor, AGTR (Anigiotensin receptor) are known as main effectors molecules of renin-angiotensin system in regulating the physiological processes of the cardiovascular system. Not only do they function as an endocrine system, but they have recently reported to regulate cell proliferation, angiogenesis, invasiveness, and viabilities via inducing intercellular signaling pathways. The aim of this study is to evaluate the role of angiotensin II and AGTR1 on cell survival and proliferation in epithelial ovarian carcinoma cells. Methods: Expressions of AGTR1 were evaluated by immunohistochemistry in epithelial ovarian carcinoma tissues and analyzed the correlation between AGTR1 expression and clinicopathological characteristics of patients. For in vitro test, we checked the level of expression for angiotensin II and AGTR1 in human ovarian cancer cell lines by Western blot. A recombinant angiotensin II and its blocker losartan were treated into the cells. For cell viabilities and proliferations were estimated by MTT assay. Results: Through checking the expression of AGTR1 in human ovarian cancer cells, we selected A2780 and HeyA8 cells for in vitro tests because these cells have relatively high expression. Exogenous treatment of angiotensin II resulted in increased cell growth of both cells. Losartan, specific blocker of AGTR1, diminished the angiotensin II-induced increased cell growth. Moreover, we identified that angiotensin II activated Akt and STAT signaling through AGTR1 and pretreatment of losartan inhibited those activations. Conclusion: In this study, we inquired into the role of angiotensin II-AGTR1 interaction in ovarian cancer. They positively regulate cell survivability and proliferation and activate intercellular signaling involving Akt and STAT via suggesting their oncogenic mechanisms. Moreover, treatment of losartan, showed antiproliferative effect by inhibiting the activations of AGTR1 mediated signaling. These results suggest that AGTR1 inhibitor like as losartan could be a novel therapeutic strategy treating this cancer.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 892. doi:1538-7445.AM2012-892
Abstract 894: Targeting ROS1 receptor tyrosine kinase gene fusions in non-small cell lung cancer
Authors: Davies Kurtis D. , Le Anh T. , Skokan Margaret C. , Theodoro Mariana F. , Varella-Garcia Marileila , Camidge D. Ross , Doebele Robert C.
Published: August 2012

Genomic rearrangements that fuse kinase domain-containing 3′ regions of tyrosine kinase genes with 5′ regions of unrelated genes are well characterized in cancer. The resulting fusion proteins often drive proliferation and invasion of tumor cells and thus represent attractive targets for therapeutic intervention. One such kinase that has been demonstrated to be involved in various genomic rearrangement events in non-small cell lung cancer (NSCLC), glioblastoma, and cholangiocarcinoma is the ROS1 receptor tyrosine kinase (also known as c-ROS and ROS). To date, three different 5′ fusion partners for ROS1 have been identified. In this study, we examined the frequency of ROS1 gene rearrangement in a panel of 428 patient-derived NSCLC tumor samples using a break-apart FISH assay. We found that approximately 1.2% of samples were positive. In positive samples, the expression of the fusion gene and the identity of the fusion partner were examined. HCC78 is a NSCLC cell line that has been demonstrated by us and others to express the SLC34A2-ROS1 gene fusion. In order to assess the cellular consequences of ROS1 inhibition, we treated HCC78 cells with two distinct small molecule kinase inhibitors that have activity against ROS1 (crizotinib and TAE684). We found that both drugs inhibited proliferation of HCC78 cells, down-regulated signaling pathways known to control cellular growth and survival, and disrupted normal cell-cycle progression. Finally, we report clinical data from a NSCLC patient with a ROS1 gene rearrangement, as detected by the FISH break-apart assay, who demonstrated tumor shrinkage when treated with crizotinib. This patient's tumor exhibited a novel ROS1 gene fusion partner. In conclusion, genomic rearrangements involving the ROS1 receptor tyrosine kinase are present in a small subset of NSCLC patients, and drugs that target ROS1 may be an effective treatment strategy for these patients.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 894. doi:1538-7445.AM2012-894
Abstract 940: Inhibition of androgen receptor activity in refractory prostate cancer cells by the novel Millennium-Takeda compound T-1759243
Authors: Schmidt Lucy J. , Nacusi Lucas P. , Sun Zhifu , Tindall Donald J.
Published: August 2012

Purpose. Prostate cancer (PCa) continues to be a leading cause of cancer death in males worldwide. In the prostate, androgens play a crucial role in both normal and cancerous growth by acting through the androgen receptor (AR), a member of the nuclear receptor super-family; hence, the AR has become a target of therapeutic intervention. The standard treatment for advanced PCa is androgen ablation therapy, initially leading to tumor regression through inhibition of AR activity. However, the success of androgen ablation therapy is often terminated by the emergence of castration- recurrent PCa (CRPC), for which there is still no cure. CRPC remains dependent on a functional AR-axis for proliferation and drugs targeting this network are continually being developed. We have examined the effects of Millennium-Takeda investigational compound T-1759243 on both androgen-responsive and androgen-refractory PCa cells in order to assess its therapeutic potential. Methods. We used PCa cell lines LNCaP, LNCaP-C42 and 22RV1 and assessed effects on cell viability and proliferation using MTS and BrdU assays. AR activity was measured using PSA-luciferase reporter constructs and protein levels by western blot. Microarray analysis with the Illumina HT-12 platform was used to identify genes affected by treatment with T-1759243, followed by real-time PCR confirmation. Pathway analysis was performed using MetaCoreTM software. Results. Our studies have revealed that T-1759243 reduces viability in all cell lines examined, regardless of androgen responsiveness. Treatment resulted in decreased proliferation in androgen-responsive cells and increased apoptosis in refractory cells. AR activity, as measured by PSA-luciferase assay, was greatly decreased in all cell lines by 10uM T-1759243 and T-1759243 abrogated the ability of synthetic androgen R1881 to increase AR activity by inhibiting nuclear translocation of the AR in refractory cells. Pathway analysis revealed changes in genes involved in cell-cycle, cell adhesion and cytoskeletal remodeling in addition to genes in androgen target pathways. Conclusions. T-1759243 is a novel AR antagonist that inhibits AR activity in both androgen-dependent and androgen-refractory prostate cancer cells. Additionally, it inhibits the ability of androgen to promote nuclear translocation of the AR and thus stimulate AR activity in castrate-resistant prostate cancer cells. Pathways affected by treatment with T-1759243 are cell-specific and dependent on AR status and may reveal novel gene targets in PCa treatment. This work was supported in part by Grant #35 from Millennium Pharmaceuticals, Inc the Takeda Oncology Company.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 940. doi:1538-7445.AM2012-940
Abstract 942: CYP3A4 epoxygenase mediates hypoxia-induced biosynthesis of epoxyeicosatrienoic acids (±)-11,12- and (±)-14,15-EET in breast cancer cells
Authors: Guo Zhijun , Mitra Ranjana , Luo Xiangghua , Capdevila Jorge , Lipscomb JohnL , David Potter A.
Published: August 2012

Introduction: CYP3A4 has recently been implicated in the growth of breast cancer cell proliferation but whether it promotes cell proliferation under conditions of hypoxia is unknown. This autocrine/paracrine growth promoting mechanism is dependent on epoxygenase activity, requires epoxygenation of arachidonic acid and can be complemented by add back of (±)-14,15-EET. Ambient tissue oxygen concentrations in tumors range from sub-microM to 50 microM. Methods: Human recombinant CYP3A4 SupersomesTM(BD Bioscience)-catalyzed epoxygenation of arachidonic acid (AA, 100 μM) reaction was performed at 37°C in the presence of a NADPH regenerating system. Oxygen concentration of the reaction solution was varied and rates of oxygen consumption were recorded with an oxygen electrode. Lineweaver Burke analysis was performed to calculate the oxygen Michaelis-Menten constant (Km). MCF7 breast cancer lines stably expressing two different CYP3A4 shRNA expression constructs were exposed to hypoxic conditions ([O2]=50 μM) and EET levels were quantified. Results: The oxygen Km for CYP3A4 was 21 μM. Under hypoxic incubation ([O2]=50 μM), (±)-8,9-EET levels were unaffected but (±)-11,12-EET and (±)-14,15-EET levels were induced 1.5 and 1.3-fold (P<0.05; Student t-test). The MCF7 CYP3A4 knock down line 3-18 line, which exhibits 80% knock down of CYP3A4, exhibited no response to hypoxia compared to the MCF7 non-target (NT) line, which exhibited 1.25 and 1.33 fold increase of (±)-11,12- and (±)-14,15-EET respectively. Remarkably, (±)-8,9-EET exhibited no induction under hypoxic conditions. Conclusions: These results indicate that CYP3A4, which is known to promote breast cancer cell proliferation, is responsive to oxygen under ambient conditions comparable to those found in hypoxic tissues, exhibiting a Km of 21 μM. These results also indicate that hypoxia induces EETs in the breast cancer line, in a fashion dependent on CYP3A4. CYP3A4 therefore provides the majority of EETs induced in breast cancer cells under conditions of hypoxia and may contribute to autocrine and paracrine breast cancer growth signals under these conditions.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 942. doi:1538-7445.AM2012-942
Abstract 944: Down-regulation of CAMKK2 by androgen deprivation induces castration-resistant prostate cancer
Authors: Mizokami Atsushi , Shima Takashi , Miyagi Toru , Kawai Keiichi , Izumi Kouji , Kumaki Misako , Jian Zhang , Keller Evan T. , Namiki Mikio
Published: August 2012

One of the mechanisms through which prostate cancer (PCa) relapses after androgen deprivation therapy (ADT) is to become androgen-hypersensitive and adapt to the low concentration of androgen during ADT. cDNA microarray analysis between PCa tissues before ADT and normal prostate tissues revealed that the level of calcium/calmodulin-dependent protein kinase kinase 2 (CAMKK2) mRNA was overexpressed 6 times in PCa more than in normal prostate. Immunohistochemical analysis of CAMKK2 protein using prostate tissue microarray showed that CAMKK2 protein was expressed well in PCa compared with normal tissue. However, the expression of CAMKK2 for the high grade PCa diminished compared with the low grade PCa. Moreover, we confirmed that the narrowness of a positive regional area of the CAMKK2 expression before ADT was a poor prognostic factor. Expression of CAMKK2 mRNA was up-regulated in the presence of DHT in LNCaP cells. Stable overexpression of CAMKK2 in LNCaP cells (LNCaP/GFP-CAMKK2), however, attenuated androgen-sensitivity. Tumorigenesis of LNCaP/GFP-CAMKK2 cells by subcutaneous injection in male SCID mice was also inhibited compared with control cells irrespective of castration. In contrast, knockdown of CAMKK2 mRNA in LNCaP cells induced androgen-hypersensitivity and stimulated LNCaP cell proliferation without DHT. Overexpression and knockdown of CAMKK2 in the presence of DHT were correlated with activation and inactivation of AMP-activated protein kinase (AMPK) that is a key kinase important for regulating cell proliferation, respectively. AMPK activation inhibited LNCaP cell proliferation. Taken together, induction of androgen-hypersensitivity after ADT may be involved in down-regulation of CAMKK2. This result may provide new therapeutic approach to keep androgen-sensitivity of PCa after ADT.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 944. doi:1538-7445.AM2012-944
Abstract 945: The identification of subgroups of obese women with differing endometrial/systemic estrogenic metabolism: Potential consequences in the development of endometrial cancer
Authors: Villavicencio Alejandra , Medina Elizabeth , Muñoz Yenny , Peñaloza Paulina , Gaete Fancy , Castro Francisco , Albornoz Catalina , Celis Miguel , Vargas Macarena , Owen Gareth
Published: August 2012

Background: Enhanced endometrial proliferation correlates obesity to type-I (estrogen-dependent) endometrial cancer (EC). However, not all obese women develop type-I EC. Our laboratory identified cycling obese women without type-I EC with differing endometrial proliferation levels: Obese High Proliferating (OHP) and Obese Low Proliferating (OLP). We propose that these differences are the result of impaired endometrial/systemic estrogenic metabolism. Objectives: To assess the endometrial activity and/or expression of estrogen metabolic enzymes, such as aromatase and sulfatase, and the endometrial/systemic level of 17β-estradiol (E2), estrone (E1), estrone sulfate (E1-S) in those subgroups of obese patients. Methodology: The endometrial tissue and blood samples were obtained from pre-menopausal women in the proliferative phase (without type-I EC) with body mass index (BMI) = 18-24.9 Kg/m2 (normal-weight, N, n=10), BMIβ 30 kg/m2 (obese, OHP, n=14; OLP, n=6) and from obese women with type-I EC (n=12). Endometrial aromatase activity was assessed by measuring the amount of 3H2O released from tritiated androstenedione (substrate), and aromatase expression was measured by immunohistochemistry. Sulfatase activity was assayed using [3H] E1-S (substrate) and the [3H] product was determined by liquid scintillation. Endometrial and serum E2, E1, E1-S levels were determined by radioimmunoassay. Results: OHP demonstrated increased endometrial activity (26%, P<0.05) and expression (71.8%, P<0.05) of aromatase, higher endometrial E2 (25%, P<0.05) and E1-S (20%, P<0.05) levels, increased circulating E2 (57.1%, P<0.05) and E1-S (42.6%, P<0.05) levels compared with OLP group. In addition, OHP did not differ from OLP in endometrial sulfatase activity and endometrial/circulating E1 levels. No differences were observed between OLP and normal-weight groups in relation to aromatase activity/expression, circulating levels of E2, E1, E1-S, and endometrial levels of E2. Interestingly, obese women with type-I EC possessed similar aromatase and sulfatase activity as OHP. Conclusions: These data suggest that the E2 produced in the endometrial tissue from OHP group could amplify the estrogenic action of estrogens delivered via the circulation and explain the higher endometrial proliferation observed in this group. Our data may help identify obese women more susceptible to develop type-I EC, allowing early intervention and a potential reduction in mortality. (FONDECYT 1110232).

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 945. doi:1538-7445.AM2012-945
Abstract 946: Discovery of a novel benzotriazole-type retinoid X receptor partial-agonist decreasing plasma glucose level in type-2 diabetes mellitus with decreased side effects
Authors: Kakuta Hiroki , Yakushiji Nobumasa , Ohsawa Fuminori , Yamada Shoya , Nakayama Mariko , Kawata Kohei , Ohta Yui , Fujiwara Chisa , Oohashi Toshitaka , Makishima Makoto , Tai Akihiro , Yasui Hiroyuki , Yoshikawa Yutaka
Published: August 2012

Insulin-independent hypoglycemic agents have attracted attention, because type 2 diabetes mellitus is reported to be associated with an increased risk of cancer due to mitogenic effect of insulin. Insulin-independent antihyperglycemic effect can be obtained by LXR activation. LXR functions as heterodimers with retinoid X receptors (RXRs). RXRs also work with PPARs, which are known as targets for improvement of insulin resistance. Since LXR/RXR and PPAR/RXR can be activated by RXR agonists alone, and we are interested in RXR agonists for new hyperglycemia agents. However, well-known RXR agonists (RXR full-agonists) show significant weight gain and triglyceride elevation. Since these side effects are caused by excess activation of RXR, we hypothesized that RXR partial-agonists might be effective to decrease plasma glucose level without these problems. As a result, CBt-PMN, which has a benzotriazole structure, was discovered as an RXR partial-agonist, and significantly decreases plasma glucose level in type 2 diabetes model mice without the side effects described above.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 946. doi:1538-7445.AM2012-946
Abstract 947: Molecular mechanism of WBP-2 coactivation function in estrogen receptor transactivation
Authors: Buffa Laura , Nawaz Zafar
Published: August 2012

The link between breast cancer and Estrogen Receptor alpha (ERα) is well established. The ERα is a ligand-inducible transcription factor that, upon binding to the hormone estrogen, regulates the expression of a variety of genes mainly involved in cell proliferation. Coactivators are proteins recruited by the hormone-activated receptor, which enhance the ERα transactivation functions acting as chromatin remodeling enzymes or adaptors between ERα and the transcriptional machinery. Our laboratory has previously identified WBP-2 (WW-domain binding protein 2) as bona fide coactivator of ERα. However, the molecular mechanism underlying WBP-2 coactivation function is not clear yet. In this study we investigate the mechanism by which WBP-2 acts as a coactivators of ERα. Our data show that knockdown of WBP-2 protein is associated with reduced expression of the ERα target gene pS2. Conversely, over-expression of the same protein results in increased pS2 expression. In order to clarify the mechanism governing these outcomes, we performed chromatin immunoprecipitation (ChIP) assays under WBP-2 knockdown conditions. We demonstrate here that WBP-2 binds to the pS2 promoter, and its knockdown is associated with decreased recruitment of the phosphorylated form of RNA PolII (associated with active transcription). Under similar conditions, the histone acetyl transferase p300 also exhibits reduced recruitment to the same promoter. Accordingly, decreased recruitment of p300 correlates with decreased histone acetylation. Collectively, our data indicate that WBP-2 enhances ERα transactivation function by facilitating the recruitment of a histone modifier enzyme that favors a relaxed chromatin structure permissive of transcription.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 947. doi:1538-7445.AM2012-947
Abstract 950: Orphan nuclear receptor DAX1 exhibits suppressive effect on prostate cancer cell growth
Authors: Jia Lin , Chan Franky Leung
Published: August 2012

The nuclear receptor superfamily comprises a large group of transcriptional factors involved broadly in many physiological functions including control of embryonic development and cellular homeostasis. In general, nuclear receptors can bind to specific DNA regulatory elements (REs) as homo- or heterodimers. DAX1 (Dosage sensitive sex reversal (DSS), adrenal hypoplasia congenita (AHC) critical region, on chromosome X, gene 1, NR0B1) is a unique ligand-independent orphan nuclear receptor, which lacks the conventional DNA-binding domain (DBD) and in some cases it functions as a coregulatory protein inhibiting the transcriptional activity of other nuclear receptors by forming heterodimers. Previous studies show that DAX1 may play an essential role in establishment and maintenance of the steroidogenic axis of development, maintenance of murine embryonic stem cell pluripotency and cancer development including ovarian, breast and endometrial cancers. A recent report identified the inverse correlation of immunoreactivity of DAX1 with Gleason score of prostate cancer. In a preliminary investigation of expression patterns of members of nuclear receptor superfamily in a panel of immortalized prostatic epithelial cell and prostate cancer cell lines by semi-quantitative and real-time PCR, we observed that DAX1 displayed a variable expression pattern with low or undetectable levels in most tested immortalized prostatic epithelial cell lines and prostate cancer cell lines (including the classical LNCaP and PC-3) but high levels in some prostate cancer cells (VCaP, DuCaP, RC-58T and DU145) and also an in vitro model of transformed immortalized human prostatic epithelial cells BPH-1CAFTD. In order to elucidate the possible functional roles of DAX1 in the prostate cancer cell growth regulation, we generated DAX1-stable expression clones in two prostate cancer cell lines, LNCaP and PC-3, which expressed low endogenous DAX1 levels, by retroviral transduction for in vitro growth characterization. Our results showed that overexpression of DAX1 in LNCaP and PC-3 cells suppressed their in vitro cell proliferation, single-cell colony formation and anchorage-independent growth capacity in soft agar. Moreover, luciferase reporter gene assay showed that DAX1 suppressed the ERRα-induced transactivation of VEGFA. Our results suggested that DAX1 might perform a suppressive growth regulatory role in prostate cancer cells. (Lin Jia is supported by a RGC Hong Kong-PhD Fellowship Scheme)

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 950. doi:1538-7445.AM2012-950
Abstract 961: Pathways of tumorigenesis promoted by the growth factor progranulin in SW-13 adrenocortical carcinoma cells
Authors: Zhang Yonghua , Ismail Amin , Bateman Andrew
Published: August 2012

Adrenocortical carcinomas are highly malignant cancers, with a very low 5 year survival rate. The SW-13 cell line originated from a stage IV adrenocortical carcinoma, but is only poorly tumorigenic in mice. It can, however, be made highly tumorigenic in vivo if it is engineered to express a limited number of growth factors including progranulin (PGRN, also called PCDGF, granulin epithelin precursor, or proepithelin) and secreted FGFs. This provides a model system to study the transition of an adrenocortical carcinoma from low to a high malignant potential. PGRN is a secreted glycoprotein growth factor that is over produced by many cancers including those of the breast, ovary, endometrium, prostate, bladder, and liver. It acts on cancer growth by increasing mitosis, decreasing apoptosis and stimulating invasion. In addition, PGRN has been implicated as a stimulator of tumor stroma growth in breast cancer. We examined the expression of PGRN in SW-13 cells at different stages of the cell cycle. Cells were synchronized using two independent agents, L-Mimosine and aphidicolin to arrest cell division. Washout of the drugs released the SW-13 cells into the cell cycles with slow (L-Mimosine) or rapid (aphidicolin) kinetics, and PGRN expression increased in parallel with the increased proportion of cells in active cell division. Depleting PGRN mRNA levels slowed reentry into the cell cycle following drug removal. Inhibition of MEK1/2, phosphatidylinositol-3 kinase (PI3K), protein kinase C (PKC) and phospholipase-C-α (PLCγ) impairs proliferation of SW-13 cells carrying only empty vector (SW-13V) with differential effects on mitosis and apoptosis. In cells with elevated PGRN, (SW-13P), the anti-proliferative effects of inhibiting MEK1/2, PI3K and PKC, but not PLCγ, are attenuated. Inhibition of the stress kinase p38 increases proliferation of SW-13V, but not SW-13P cells, suggesting that PGRN and p38 have opposing effects on proliferation. Inhibition of p38 enhances the phosphorylation of MEK1/2 in SW-13V cells, while inhibiting PKC decreases it, suggesting that PKC and p38 pathways interact with the PGRN-regulated MEK1/2 signaling cascade. Transcriptional profiling indicated that expression of PGRN modulated levels of proteins in the Wnt and Notch-signaling pathways. These results suggest that PGRN expression may be coordinated with the cell cycle, and, may promote tumorigenesis by intervening in several signaling pathways.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 961. doi:1538-7445.AM2012-961
Abstract 963: Epigenetic silencing of cancer-specific methylation may converge on therapeutic targets on human cancers
Authors: Yamashita Keishi , Kim Myoung Sook , Ooki Akira , Kato Hiroshi , Waraya Mina , Kawamata Hiroshi , Watanabe Masahiko , Sidransky David
Published: August 2012

(Background) We have identified numerous candidate tumor suppressor genes (TSGs) which are inactivated by cancer-specific CpG island methylation. We reviewed differential patterns of cancer-specific methylation in esophageal squamous cell carcinoma, gastric adenocarcinoma, and colorectal adenocarcinoma. (Matherials and Methods) A modified pharmacological unmasking microarray in combination with tissue expression patterns identified novel cancer-specific methylation in each organ site, and we tabulated methylation frequency for each type of cancer. (Results) (1) In esophageal squamous cell carcinoma, we discovered cancer-specific methylation for NEFH (84%), NMDAR2B (78%), DCC (74%), cyclin A1 (60%), CRBP1 (52%), HOPX (50%), trypsinogen-4 (50%), and PGP9.5 (42%). (2) In gastric adenocarcinoma, we validated cancer-specific methylation for HOPX (87%), Reprimo (78%), PGP9.5 (70%), NMDAR2B (70%), and RIZ1 (40%). (3) In colorectal adenocarcinoma, we identified cancer-specific methylation for Beta 4 GalT1 (82%), Oncostatin MR (80%), DFNA5 (65%), LIFR (65%), and HOPX (52%). (4) From our estimates, about 300 genes were frequently methylated specifically in cancer tissues, and among them, and around 70% of these genes were upstream or downstream of the p53 pathway (NMDAR2AB, DCC, cyclin A1, PGP9.5, HOPX, Reprimo, DFNA5). Apoptotic pathways other than those in the p53 pathway, including death receptor signaling was also observed. Another 30% of methylated genes antagonize unique oncogenic pathways in individual cancers. Either NEFH or HOPX was involved in inactivation of pAkt through an unknown mechanism or PTEN induction in ESCC. RIZ1 uniquely inactivated in gastric cancer, is an inhibitor of the IGF receptor pathway. Oncostatin M R or LIFR in CRC are inhibitors of pStat3. All inactivated TSG candidates were demonstrated to be robustly reactivated by de-methylating agents. (Conclusion) In GI cancers, numerous genes involved in p53 activation are commonly suppressed in expression, and epigenetic reversion of p53 activity may be beneficial for killing cancer cells more efficiently. Moreover, unique oncogenic inhibitors will need to be developed for specific targets in similar but related pathways for varied organ sites.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 963. doi:1538-7445.AM2012-963