bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 5029: Upregulation of miRNA27, miRNA125a and 125b in ERalpha-negative breast cancers
Authors: Lehmann Tomasz P. , Korski Konstanty , Ibbs Matthew , Breborowicz Jan , Grodecka-Gazdecka Sylwia , Gryczka Robert , Jagodzinski Pawel
Published: August 2012

MicroRNAs (miRNAs) are a major class of small endogenous RNA molecules that post-transcriptionally inhibit gene expression. Many miRNAs have been implicated in the human breast cancer. We show here the correlation between breast cancer types characterized upon histological and immunohistochemical analysis and miRNA expression in 22 Polish patients. The group was divided into three categories: ERalpha-negative / ERalpha-positive, HER2-negative / HER2-positive and lymph node -negative / lymph node -positive (N-/N+) cases. Surgically removed tumors were congealed in liquid nitrogen and subsequently small RNA was extracted. We investigated the level of miR-17-5p, miR-27, miR-125a, miR-125b and miR-206 using real-time PCR TaqMan probes. Let-7 miRNA and U6 RNA were used as reference genes. We observed upregulation of the subsequent suppressor miRNAs miR-27, miR-125a and 125b in ERalpha-negative tumors (p<0.05). Comparison of expression of miR-17-5p, miR-27, miR-125a, miR-125b and miR-206 in N- and N+ samples did not reveal any significant differences. We also observed a tendency to lower level of expression of all investigated miRNAs in HER2-positive patients in comparison with HER2-negative. We concluded that miR-27, miR-125a and miR-125b may play an important role in the regulation of ER-alpha expression in breast cancer cells. They could also be regarded as surrogate markers of ER-alpha -negativity. However, the small number of patients included to the study warrants further investigation in the larger cohort of breast cancer 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 5029. doi:1538-7445.AM2012-5029
Abstract 5030: Identification of the Her-2 expression-regulating miRNAs by microdissection and RT-PCR in breast cancer tissue
Authors: Hao Yubin , Xing Hangying , He Chunnian
Published: August 2012

Her-2/neu oncogene is overexpressed in human breast cancer and is correlated with the tumor cell proliferation, metastasis, and resistance against chemo- and hormonotherapy. The expression levels of both Her-2/neu gene and HER-2 protein are recommended for evaluation of treatment efficacy as well as for selection of treatments. However, clinical studies have shown that the Her-2/neu gene and the HER-2 protein are differently expreesed in 10-15% of human breast cancers and we hypothesized that the expression difference might be related to the post-transcriptional regulation of the Her-2/neu gene by microRNAs (miRNAs). To identify the specific miRNAs, we first analyzed 120 human breast cancer samples for the Her-2/neu gene amplification and protein expression with fluorescence in situ hybridization (FISH) and immunohistochemistry (IHC). Fourty-four cancer samples (36.7%, 44/120) showed overexpression of HER-2 protein with IHC (IHC+) and 26 samples (26.5%, 26/98) exhibited Her-2/neu gene amplification with FISH (FISH+). Interestingly, five samples exhibited amplification of the Her-2/neu gene, but absence of the HER-2 protein expression (FISH+/IHC-). We then dissected the FISH+/IHC- tumor cells using laser capture microdissection from the five samples. Tumor cells with FISH+/IHC+ from another set of five samples were also dissected and analyzed as the control. Based on TargetScanHuman and literature search, five candidate miRNAs including miR-125b, -1224-3p, -1296, -193a-5, and -331-3p were screened with quantitative real-time RT-PCR and their expression levels in the FISH+/IHC- cells were 3.1-, 2.7-, 1.7-, 1.7-, and 1.3-fold higher than in the FISH+/IHC+ cells, respectively, with a significant difference for miR-1224-3p and miR-1296 (both P < 0.01). These results indicate that miR-1224-3p and miR-1296 may be responsible for the different expressions of Her-2/neu gene and its protein by regulating the Her-2/neu gene posttranscription, thus down-regulating the HER-2 protein expression in FISH+/IHC- breast cancer cells.

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 5030. doi:1538-7445.AM2012-5030
Abstract 5031: miR-21 targets TGF-β Pathway in breast cancer
Authors: Chen Liang , Wang Meng , Peng Jin , Teal Christine , Stamatakos Michael , McCaffrey Timothy , Fu Sidney W.
Published: August 2012

MicroRNAs (miRNAs) are endogenous non-coding RNAs (∼22 nt), which regulate the stability and translation of coding mRNAs. miRNA dysregulation is observed in a variety of cancers, including breast cancer. Our previous studies, by miRNA expression profiling using archived FFPE tissues, identified a set of miRNAs that are differentially expressed during breast cancer progression. Using ANOVA test, we identified 8 clusters of miRNAs, which discrete the normal and disease lesions, such as ADH, DCIS and IDC. miR-21 has been well documented as an oncogene, while miR-200c/b are reported as biomarkers for primary hepatocellular carcinoma, and miR-200c as an independent prognostic factor in pancreatic cancer. Our study shows that miR-21 consistently expresses high level in pre-cancerous lesions, i.e. ADH and DCIS, which indicates that miR-21 plays an important role in breast cancer initiation and progression. However, the exact mechanism is not clear. To test the effects of miR-21 inhibition in both ER+ and ER- breast cancer cells, we transfected anti-miR-21 oligos and scrambled oligo mocks into human breast cancer cells, MCF-7 (ER+) and Hs578T (ER-). We observed a significantly increased expression of MSH2 and SMAD7, when miR-21 was knocked down by 60%-80%. Both MSH2 and SMAD7 are key players in TGF-β signaling pathway, which is well known for its anti-mitogenic function during tumor initiation. These findings help establish miR-21 as an important oncogene that targets a network of TGF-β in breast 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 5031. doi:1538-7445.AM2012-5031
Abstract 5032: New insights of miR-221 and miR-222 cluster functions in Burkitt lymphoma.
Authors: Consiglio Jessica , Luca Luciana De , Acunzo Mario , Galasso Marco , Rocci Alberto , Sapienza Maria-Rosaria , Piccaluga Pier Paolo , Vecchione Andrea , Zanesi Nicola , Volinia Stefano , Croce Carlo Maria , Pichiorri Flavia
Published: August 2012

Burkitt lymphoma (BL) is a mature aggressive B-cell neoplasm, with a characteristic clinical presentation, morphology and immunophenotype. Several studies have indicated the importance of miRNAs in B cell maturation and in the development of B cell lymphomas. MicroRNAs (miRNA) are a class of naturally occurring, small, non-coding RNA that can control gene expression by targeting mRNA molecules for translational repression or cleavage. They are usually expressed in a tissue-specific manner and play important roles in apoptosis, differentiation and cell proliferation; therefore their deregulation may be involved in carcinogenesis or tumor progression by altering normal gene expression patterns. Over the past years microRNAs signatures have been described to characterize and classify different types of BL or to investigate the expression of miRNAs possibly regulated by c-Myc in BL cases positive or negative for Myc traslocation. Howhever, it remained unclear the functional role of miRNAs that have been found differentially expressed and no further studies have been conducted. We performed miRNA expression profile to gain further insights into the molecular pathology of BL. We conducted array analysis on a set of 5 sporadic BL patients, 3 endemic BL patients, 9 reactive tissues and 11 cases of mononucleosis. A common trend of miRNAs altered expression was also observed by NanoString analysis in 10 BL cell lines compared to 5 normal CD-19+ B cells. Among several miRNAs previously described be deregulated in BL we identified a severe down-regulation of miR-221, miR-222 in all classes of comparisons we analyzed. The down-regulation of miR-221 and miR-222 associated to BL has been also confirmed by q-RT-PCR method in a different cohort of BL patients (20) compared to the healthy controls (6). When miR-221 and miR-222 expressions have been restored in BL cancer cell lines, lacking of their expression, by gene expression profile we identified the differentially expression of several genes involved in ncRNAs processing, ncRNA metabolic process and also in the regulation of cell differentiation and cell cycle. Furthermore, functional experiments identified many of these genes as new direct targets of miR-221 and miR-222. In conclusion, our study reveals new insights into the functional significance in loss of miR-221 and miR-222 expression in BL pathogenesis.

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 5032. doi:1538-7445.AM2012-5032
Abstract 5033: Relationship between microRNA expression and Gleason grading system in prostate cancer
Authors: Tsuchiyama Katsuki , Ito Hideaki , Taga Minekatsu , Oshinoya Konosuke , Nagano Kenichi , Yokoyama Osamu , Itoh Hiroshi
Published: August 2012

Background: Recent studies have shown that some microRNA (miRNA) expression profiles are associated with clinicopathological findings, including “Gleason score (GS)” in human prostate cancer (PC). However, the direct relationship between “Gleason pattern (GP)” and miRNA expression remains unclear. In this study, we investigated the miRNA expression profile in each GP (GP 3, GP 4, and GP 5). Methods: Formalin-fixed, paraffin-embedded (FFPE) tissue samples obtained from radical prostatectomy (patient set 1, n = 43, including [GP 3] n = 22, [GP 4] n = 35, and [GP 5] n = 12) and prostate needle biopsy (patient set 2, n = 9, [GP 4] n = 9) were used. Cancer tissues and adjacent normal counterparts were collected separately using laser-captured microdissection with subsequent isolation of total RNA. Real time reverse transcription polymerase chain reaction (RT-PCR) was performed to determine the relative expression of miRNAs, including miR-31, -34c, -96, -182, -183, -205, -221, and miR-222, which are currently reported to be involved in the progression of PC. Results: In the radical prostatectomy samples (patient set 1), relative expression (mean ± SE) of miR-31, miR-34c, and miR-205 in every GP was significantly decreased (miR-31: [GP 3] 0.028 ± 0.007, [GP 4] 0.047 ± 0.017, and [GP 5] 0.071 ± 0.022; miR-34c: 0.208 ± 0.066, 0.419 ± 0.219, and 0.210 ± 0.054; and miR-205: 0.021 ± 0.008, 0.015 ± 0.003, and 0.050 ± 0.023, all p-values < 0.01) compared to normal counterparts. However, there was no significant difference between GP 3, GP 4, and GP 5. Meanwhile, in GP4, expression of miR-31, miR-182, and miR-205 in tissues obtained from high-grade cancer (GS 8 or GS 9) were significantly higher than those in tissues obtained from intermediate-grade cancer (GS 7) (miR-31: [high grade] 0.071 ± 0.027, [intermediate grade] 0.011 ± 0.003, p = 0.040; miR-182: 1.745 ± 0.278, 0.864 ± 0.136, p = 0.021; and miR-205: 0.022 ± 0.005, 0.005 ± 0.002, p = 0.002, respectively). Validation testing of biopsy samples (patient set 2) revealed that the relative expression of miR-182 was similarly and significantly higher in high-grade cancer tissue (high grade: 1.863 ± 0.381, intermediate grade: 0.717 ± 0.196, p = 0.043). Conclusion: The expression of miR-182 differed by cancer grade even in the same GP 4, and this difference was detected in both biopsy and radical prostatectomy samples. Our findings suggest that evaluations of miRNA expression with respect to Gleason grading in biopsy samples may contribute to more accurate preoperative cancer risk evaluation.

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 5033. doi:1538-7445.AM2012-5033
Abstract 5036: MicroRNA expression profiling potential for human breast cancer diagnosis using a bead-based microRNA-specific capturing method
Authors: Tran Kathy , Xu Tom , Stevens Junko
Published: August 2012

MicroRNAs (miRNAs), a family of small, endogenous, non-coding (∼17-24 nucleotides) nucleic acids, were initially discovered in 1993, but the discovery of a second miRNA led to their use as molecular markers of disease and potential therapeutic targets. MiRNAs regulate RNA translation, play a role in cell proliferation, control timing of organism development, and are associated with carcinogenesis. Because of their regulatory function in cell differentiation and renewal during physiologic and malignant conditions, miRNAs are emerging as a new class of effective biomarkers for cancer research. The miRNA expression profiling of tumor cells will allow for the identification of prognostic markers to indicate potential targets for patient- or disease-specific therapies. Three criteria important for profiling miRNAs are ease of use, simplicity and sensitivity. We have designed and developed a new method to quickly extract and purify specific miRNAs for detection using our current reverse transcription and real-time quantitative PCR workflows. The method involved 1μm-diameter magnetic beads conjugated with anti-miRNA oligoncleotides to capture these select miRNA targets from blood, plasma, and other tissues. The miRNAs were then transcribed into cDNA and subsequently used as templates for TaqMan® qRT-PCR analysis. We used this method to evaluate the miRNA signatures from normal and cancerous human breast modeled by cell lines and represented by formalin-fixed, paraffin-embedded tissues.

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 5036. doi:1538-7445.AM2012-5036
Abstract 5037: Identifying differentially expressed microRNAs in retinoblastoma
Authors: Martin Joshua , Bryar Paul , Mets Marilyn , Weinstein Joanna , Vanin Elio F. , Costa Fabricio F. , Soares Marcelo B. , Laurie Nikia A.
Published: August 2012

Retinoblastoma, the most common pediatric cancer of the eye, is a devastating and sometimes fatal pediatric cancer. Within the United States, the majority of retinoblastoma patients are diagnosed before their 2nd birthday, and many lose their sight due to this disease. Approximately 75% of the retinoblastoma patients in the United States have unilateral disease, and treatment for many unilateral patients with advanced disease involves enucleation (removal of the eye). Therefore, new more effective targeted therapies for retinoblastoma could save a child's quality of life by preserving their sight. Outside of the United States, advanced retinoblastoma is an even greater clinical challenge in low-income countries, where the mortality rate among children diagnosed with advanced retinoblastoma is as high as 70%. Currently, the chemotherapeutic treatments for retinoblastoma involve the use of broad-based drugs. However, therapies targeted directly to aberrant signaling pathways may provide more effective therapy for this disease. MicroRNAs, short noncoding RNA transcripts that can regulate the expression of target genes, are known to affect the progression of many different tumor types. MicroRNAs (miRNAs) are also ideal therapeutic targets because they are amenable to therapeutic manipulation. To identify miRNAs associated with retinoblastoma progression, we have conducted miRNA profiling studies on 12 late-stage human retinoblastoma tumors. Our analysis has led to the identification of 19 differentially expressed miRNAs (p<0.05) in retinoblastoma as compared to normal human retina. From those 19 miRNAs, 15 miRNAs are newly associated as being differentially expressed in retinoblastoma. These miRNAs could serve as potential therapeutic targets for retinoblastoma due to their known involvement in viability, proliferation, cell cycle regulation, and apoptosis in other tumor types. This is an essential step in the discovery of miRNAs associated with retinoblastoma progression, and in the identification of potential therapeutic targets for this disease.

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 5037. doi:1538-7445.AM2012-5037
Abstract 5182: Real-time molecular imaging of αv-integrin GFP-expression in osteosarcoma cells in vitro and in vivo
Authors: Tome Yasunori , Sugimoto Naotoshi , Yano Shuya , Momiyama Masashi , Maehara Hiroki , Tomita Katsuro , Tsuchiya Hiroyuki , Kanaya Fuminori , Hoffman Robert M.
Published: August 2012

We describe here real-time imaging of αv integrin-GFP expression in osteosarcoma cells (143B) in vitro and in vivo. 143B cells were stably transfected with an αv integrin-GFP vector. Confocal microscopy demonstrated that αv integrin immunofluorescent staining colocalized with αv integrin-GFP fluorescence. In vitro, when αv integrin-GFP osteosarcoma cells were seeded on a dish coated with fibronectin, which bonds αv integrin. αv integrin adhesion plaques were observed by confocal microscopy using the Olympus FV1000. When αv integrin-GFP-expressing 143B cells (1×106) were transplanted in the tibia or injected subcutaneously in nude mice, the cells aligned along collagen orthotopic fibers. In the orthotopic model, osteosarcoma cells punctate expression of αv integrin-GFP was imaged in the osteosarcoma cells as they invaded muscular tissue. In the subcutaneous model, osteosarcoma cells, strongly expressing αv integrin-GFP, were observed around the blood vessels in the tumor. These results show that αv integrin-GFP allows the real-time imaging of the role of αv integrin during cancer cell invasion allowing the further understanding of its role in the process.

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 5182. doi:1538-7445.AM2012-5182
Abstract 5183: Raster-image-correlation spectroscopy of paxillin-GFP-expressing breast cancer cell in vitro and in vivo
Authors: Suetsugu Atsushi , Digman Michelle , Sabatini Federica , Moriwaki Hisataka , Saji Shigetoyo , Gratton Enrico , Hoffman Robert M.
Published: August 2012

Raster-image-correlation spectroscopy (RICS) is a noninvasive technique to detect and quantify events in the living cell, including concentrations of molecules and their diffusion coefficients. Any cell containing a fluorophore that can be imaged with a laser scanning microscope can be analyzed with RICS. We obtained RICS images with an Olympus FluoView FV1000 confocal microscope using Olympus FluoView software to acquire data and SimFCS software to perform RICS analysis. Paxillin is involved in the assembly of focal adhesions, which was linked to green fluorescent protein (GFP) for the current study. In this study, we describe RICS of paxillin-GFP expression in breast cancer cells (MDA-MB-231) in vitro and in vivo. Slow-moving membrane-bound paxillin proteins were measured in live breast cancer cells in vitro. Paxillin-GFP-expressing breast cancer cells (1×106) were injected in the epigastric cranials vein of the nude mouse. Paxillin-GFP-expressing breast cancer cells became attached to the inner vessel wall within 3 hours after injection. Rapidly-moving cytosolic paxillin-GFP molecules were imaged with RICS. With the ability to measure the molecular dynamics of paxillin in cancer cells in vitro and in vivo by RICS, we are now capable of studying the role of both slow-moving paxillin in the cell membrane and rapidly-moving cytosolic paxillin in cancer-cell behavior.

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 5183. doi:1538-7445.AM2012-5183
Abstract 5186: A new mode of integrin–Ecadherin cross talk that modulates invasion and metastasis
Authors: Danen Erik H.
Published: August 2012

Cellular interactions with the extracellular matrix (ECM) are mediated by transmembrane receptors of the integrin family. These interactions coordinate signal transduction cascades impinging on cell survival, proliferation, and migration. Ablation of the β1 integrin gene attenuates initiation and growth of breast and skin cancers and β1 antibodies sensitize breast tumors in mice to radiotherapy. However, the role of β1 integrins in breast cancer progression from a localized tumor to metastatic disease is unknown. We show that peptide blocking or gene silencing of β1 integrins can cause a shift from cohesive multicellular strand invasion to individual cell migration, which acts pro-metastatic in breast cancer cells. While tumor growth of β1 integrin-depleted breast cancer cells is reduced, intravasation and lung metastasis of cells from these small tumors in an orthotopic mouse model is dramatically enhanced, as is migration in a zebrafish xenograft model. Depletion of β1 integrins alters the balance between miR-200 miRNAs and ZEB transcriptional repressors leading to a transcriptional downregulation of E-cadherin, which is essential for the induction of individual cell migration and enhanced metastasis. These findings demonstrate that disturbed integrin-mediated interactions with the ECM in cancer cells can alter cell migration strategies and metastatic potential through a miRNA-transcription factor network that controls cell-cell adhesion.

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 5186. doi:1538-7445.AM2012-5186
Abstract 5187: Urokinase plasminogen activator receptor (uPAR) and integrin α5β1 regulate plasminogen activator inhibitor-1 (PAI-1) activity in medulloblastoma cells
Authors: Nalla Arun Kumar , Asuthkar Swapna , Gujrati Meena , Dinh Dzung H. , Rao Jasti S.
Published: August 2012

The urokinase plasminogen activator (uPA) system is a dynamic extracellular protease system that regulates both proteolytic and non-proteolytic events associated with cancer progression. In earlier studies, we have demonstrated that radiation-induced cell adhesion was associated with uPAR expression and downregulation of uPAR effectively inhibited radiation-induced cell adhesion of medulloblastoma cells. Herein, we further investigated the impact of uPAR downregulation on plasminogen activator inhibitor (PAI-1), a key regulator component of the uPA system, and its role in cell adhesion. With radiation treatment, the levels of uPAR and PAI-1 increased in D283 and UW228 cells. Surprisingly, knockdown of uPAR elevated the levels of PAI-1. The increase in PAI-1 levels in uPAR-knocked down cells was regulated by activation of cJUN/CREB signaling molecules. Moreover, studies show that the reduced interaction between uPAR and integrin α5β1 plays a critical role in PAI-1 release into the extracellular matrix, thereby enhancing the cell detachment process. Incubation of medulloblastoma cells with Tiplaxtinin-PAI-039, a potent PAI-1 activity inhibitor, increased the association of uPAR with integrin α5β1 and cell adhesion. Interestingly, prolonged inhibition of PAI-1 activity adversely affected cell viability; we were able to revert this effect by exogenously supplementing cells with recombinant PAI-1. Moreover r-PAI-1 showed no significant effect on cell adhesion whereas it increased the association of uPAR with integrin α5β1. Expression of full-length (FL) uPAR elevated uPA and PAI-1 levels both at the transcriptional and the translational levels. These increased PAI-1 levels play a pivotal role in regulating uPA activity by binding and translocating integrin α5β1 towards the uPA/uPAR complex. Taken together, the results of the present study lead us to conclude that levels of uPAR and integrin α5β1, and their association on the cell surface dictate the function of PAI-1 to maintain extracellular homeostasis.

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 5187. doi:1538-7445.AM2012-5187
Abstract 5189: N-cadherin promotes metastasis by enhancing motility through Akt3 suppression
Authors: Yao Jiahong , Hazan Rachel
Published: August 2012

Here we show that in vivo mammary expression of N-cadherin in the PyMT model which enhances breast tumor metastasis results in selective inhibition of Akt3 expression and phosphorylation. Similarly, exogenous expression of N-cadherin in PyMT tumor cells which enhances motility caused a dramatic reduction in Akt3 expression and activation. Moreover, knockdown of Akt3 in PyMT cells enhanced cell motility, disrupted mammary morphogenesis but had no effect on cell proliferation. Conversely, overexpression of constitutively active Akt3 inhibited cell motility, suggesting signaling through Akt3 relays motility suppression by N-cadherin. Taken altogether, these findings demonstrate that N-cadherin suppresses Akt3 to promote cell motility and highlight the intricate regulation of the AKT pathway by N-cadherin during metastasis.

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 5189. doi:1538-7445.AM2012-5189
Abstract 519: Identification of a novel target for antibody therapy of breast cancer
Authors: Okano Fumiyoshi , Saito Takanori , Ido Takayoshi , Kurihara Akira , Kobayashi Shinichi , Narita Yoshinori , Minamida Yoshitaka , Sato Masahiro , Toriyama Yuko , Yonehara Tetsu
Published: August 2012

Identification of breast cancer-specific antigens may promote development of safe and successful immunotherapy of breast cancer. Caprin-1 has been known to be an intracellular protein related to cell proliferation as a function, but it has not been reported to be a target for the treatment of cancer. Here we report that this molecule is a novel breast cancer antigen which can be targeted for antibody therapy. Caprin-1 is highly expressed in at least 70% of breast cancers based on the results of immunohistochemical staining of human several breast cancer tissues, but hardly expressed in human normal tissues. Importantly, a part of this molecule is highly expressed in extracellular region of many breast cancer cells. A mouse monoclonal antibody raised against the extracellular domain of Caprin-1 showed anti-tumor effects in all tumor-bearing mouse models in which various cancer cells expressing Caprin-1 were implanted. The monoclonal antibody induced complete regression in one of the tumor-bearing models. Humanized antibody has been prepared and preclinical studies are currently underway.

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 519. doi:1538-7445.AM2012-519
Abstract 5190: DNA aptamer-targeted periostin inhibits adhesion and migration of breast cancer
Authors: Lee Yu Jin , Kim Il Shin , Kim Yoon Dong , Lee Kyung Min , Noh Dong-Young , Kim Kyong-Tai , Ryu Sung-Ho , Suh Pann-Ghill
Published: August 2012

Tumor metastasis is multiple step pathological process involved in the final phase of tumor development. During this process, tumor cells obtain invasiveness and metastatic potential. Periostin, a mesenchyme-specific gene, has emerged as critical contributor of tumor metastasis and angiogenesis. Clinical evidence has supported that periostin are highly expressed in several cancers including breast, where it is associated with a poor outcome. Thus, periostin is a potential therapeutic target for the regulation of breast cancer growth and metastasis. In this study, we generated and characterized a DNA aptamer directed against human periostin (PNDAs) through utilization of Advanced-SELEX process. Aptamers have been selected that bind to periostin with nanomolar binding affinity (Kd: 1nM) and specificity. Furthermore, PNDA specifically binds to periostin which is expressed in breast cancer tissues and serum. In addition, PNDA treatment led to a reduction of integrin-mediated breast cancer cell migration and adhesion by 50%. Also, PNDA can significantly decrease activation of various components of integrin signal transduction pathways and their downstream effector molecules. Together, our data suggest that DNA aptamer targeting periostin may have potential as an agent to inhibit breast cancer growth and metastasis.

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 5190. doi:1538-7445.AM2012-5190
Abstract 52: Gene expression profiling of breast cancer associated fibroblasts and their adjacent counterparts
Authors: Al-Rakan Maha A. , Colak Dilek , Al-Bakheet Albandary , Kaya Namik , Aboussekhra Abdelilah
Published: August 2012

Abstract Breast cancer has a major impact on the health of women worldwide including Saudi Arabia, where it is considered the most frequently diagnosed cancer (∼22% of all female cancers) and the leading cause of cancer deaths among women. Breast carcinomas are complex neoplasms that develop by the accumulation of different mutations in the epithelial cells. However, increasing evidence suggests that changes in the cellular microenvironment contribute to tumorgenesis through paracrine effects. Fibroblasts, the predominant cells of the stromal breast carcinomas, play an important role in the development and spread of cancer cells. However, the nature and the mediators of the crosstalk between cancer cells and their stromal fibroblasts are still not well defined. In this study we performed genome wide expression analysis on 5 Carcinoma-Associated Fibroblasts (CAFs) and their corresponding Tumor Counterpart Fibroblasts (TCFs) (from the same breast cancer patients) as compared to 3 normal breast fibroblasts (NBFs) from breast cancer free patients admitted for plastic surgery. To this end, Affymetix's latest Gene Chip® Human Genome U133 Plus 2.0 Array, which has more than 54,000 probe sets, was used. A threshold of ≤2≥ fold was considered as significant difference in the analysis of the microarray data. We performed 3 different comparisons; CAFs with TCFs, CAFs with NBFs and TCFs with NBFs. The analysis of the microarray data showed that the number of genes that were differentially expressed between CAFs and NBFs reached 101, and only 42 genes were differentially expressed between CAFs and TCFs. Interestingly, 77 genes were found to be differentially expressed between TCFs and NBFs. This data was confirmed by quantitative RT-PCR. Next, we used Ray Bio® Human cytokine Antibody Array 5 Map, which has 80 probed cytokines, and showed differential expression profile of different cytokines secreted by TCF, CAF and NBF cells, confirming that TCFs are different than CAFs and NBFs indicating that TCFs are indeed active stromal fibroblasts. Moreover, we examined the expression level of α-SMA, TGF-β and SDF-1 proteins (3 well known markers of active fibroblasts) and found their expression higher in TCFs than NBFs. In addition, we performed ELISA against SDF-1, VEGFA and IL-6 (3 cytokines known to promote breast carcinogenesis) and found their levels higher in TCFs than in NBFs conditioned media. Therefore, despite the fact that TCFs exist in histologically normal breast tissues, they are not physiologically normal, but rather present some features of active fibroblasts and thereby they may participate in breast cancer development / recurrence.

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 52. doi:1538-7445.AM2012-52
Abstract 520: Regulation of natural killer cell development and antitumor immunity by the IL-15 system
Authors: Lee Gilbert A. , Liou Yae-Huei , Wang Szu-Wen , Jiang Si-Tse , Liao Nan-Shih
Published: August 2012

Natural killer (NK) cells are innate immune cells involved in tumor surveillance. The development and effector function of NK cells require IL-15 signal, which is “trans-presented” to IL-15Rβγ on NK cells by IL-15Rα on neighboring cells. Because the IL-15Rα intracellular (IC) domain has the capacity to recruit signaling molecules, we generated knock-in (KI) and transgenic (Tg) mice that lack the IC domain to assess independently the role of the IL-15 trans-presentation level. In this study, we found that the IL-15Rα level on bone marrow-derived dendritic cells (BMDCs) generated by KI and Tg mice determines the level of Stat5 phosphorylation in NK cells, thus offering the opportunity to study quantitative effects of IL-15 trans-presentation on NK cell development and function in vivo. We also found that NK cell homeostasis, mature NK cell differentiation, and acquisition of effector functions require different levels of IL-15 trans-presentation input to achieve full status. In order to investigate the effects of IL-15 trans-presentation level in anti-tumor immunity in vivo, we established the tumor inoculation experiment. Our preliminary data showed that the growth of B16/OVA melanoma increased in Il15−/− mice in comparison to WT mice. We will assess the role of the IL-15 system in anti-tumor immunity.

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 520. doi:1538-7445.AM2012-520
Abstract 5200: Nestin regulates stem cell functions of pancreatic cancer cells
Authors: Matsuda Yoko , Hagio Masahito , Yanagisawa Yuji , Suzuki Taeko , Kawamoto Yoko , Kawahara Kiyoko , Naito Zenya , Ishiwata Toshiyuki
Published: August 2012

Introduction: Nestin, a class VI intermediate filament, is expressed in pancreatic exocrine progenitor cells. Previously, we reported that 30% of PDAC cases expressed nestin in cancer cells, and its expression was correlated with invasion (Kawamoto, et al. Hum Pathol 2009). Knockdown of nestin using shRNA in human PDAC cell lines inhibited cell migration and invasion in vitro and liver metastasis in vivo. Restoring the expression level of nestin returned the inhibition of cell migration and invasion to the previous level (Matsuda, et al. Cancer Biol Ther 2011). In this study we analyzed the expression and roles of nestin in pancreatic cancer stem cells. Methods: Expressions of stem cell markers and nestin were analyzed using immunocytochemistry and real-time PCR. To assess cancer stem cells, a sphere formation assay was performed as follows: cells were grown in an ultra-low attachment surface plate supplemented with epithelial growth factor and fibroblast growth factor 2. Nestin-regulating molecules were clarified by DNA microarray analysis. Results: The expression level of nestin was high in sphere-forming PDAC cells, and its expression levels correlated with sphere-forming ability. In DNA microarray analysis using nestin shRNA-transfected clones and nestin-expression vector transfected-clones, at a 2-fold cut-off, only transcriptional factor 4 (TCF4) showed a compatible change coincident with nestin expression. It has been reported that TCF4 is involved in the Wnt pathway, and negatively regulates the transcription of NANOG. In real-time PCR, expression levels of TCF4 and NANOG correlated with nestin expression level. Conclusion: Nestin expression levels correlated with sphere-forming ability and expression levels of TCF4 and NANOG. These results indicate that nestin regulate stemness via TCF4 and NANOG.The expression of nestin is associated with highly metastatic cancer stem-like cells, and nestin regulates migration, invasion, and metastasis by altering the pancreatic cancer stem cell function.

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 5200. doi:1538-7445.AM2012-5200
Abstract 5204: Mechanisms of Notch4-Nodal regulation of the aggressive melanoma phenotype
Authors: Hardy Katharine M. , Kirschmann Dawn A. , Seftor Elisabeth A. , Kirsammer Gina T. , Strizzi Luigi , Hendrix Mary JC
Published: August 2012

Metastatic melanoma is a highly aggressive skin cancer with a poor prognosis. The current lack of effective therapies for treating metastatic melanoma exemplifies the desperate need for the identification of new targets and the development of new therapies. Nodal is an embryonic signaling molecule from the TGFβ superfamily that is not typically expressed in adult tissues but is reactivated in a number of aggressive cancers including melanoma, and breast and prostate carcinomas. In a study recently published by our group, we determined a connection between the Notch and Nodal pathways in aggressive melanoma. We identified a specific correlation between the expression of Notch4 and Nodal in aggressive melanoma cell lines and in advanced stage human melanomas. By inhibiting Notch4 expression or function, we established a link between Notch4 and Nodal signaling in promoting the aggressive phenotype of metastatic melanoma cells in vitro. Notch4 regulation of Nodal expression was identified as important in cellular plasticity, since inhibition of Notch4 function impaired the ability of aggressive cells to engage in vasculogenic mimicry (de novo formation of vascular-like networks by non-endothelial tumor cells). Notably, vascular-like network formation could be partially rescued by recombinant human Nodal, suggesting both pathways are important for this phenomenon. To extend our published observations, we utilized neutralizing antibodies to Notch4 and to Nodal, and compared gene expression profiles. From this, we identified a mechanism of feedback between signaling pathways that controls the expression of components of both pathways, including Nodal, Notch4, and the Notch ligand, Jagged2. Since Notch4 is enriched in the subpopulation of cells that form vascular-like networks in melanoma, we specifically analyzed the expression of angiogenesis signature genes previously associated with vascular-like network formation, and determined that inhibition of Notch4 or Nodal function downregulates a large group of these genes including members of the VEGF, angiopoietin, MMP, and cadherin families. We are currently investigating the hypothesis that the Notch4-Nodal signaling axis may be a master regulator of the vascular-like phenotype in aggressive melanoma cells. We suggest that inhibition of Notch4 and/or Nodal function may offer a potential molecular targeting strategy for metastatic melanoma therapy.

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 5204. doi:1538-7445.AM2012-5204
Abstract 5208: Overexpression of EZH2 increases multipotent mammary stem cell self-renewal and differentiation
Authors: Li Xin , Toy Katherine , Kleer Celina G.
Published: August 2012

BACKGROUND: A role for EZH2 in stem cell maintenance was recently reported. Our lab has previously demonstrated that overexpression of EZH2 accelerates the initiation of ErbB2-induced mammary tumors. To understand underlying mechanism, we investigated the role of EZH2 in regulation of stem cells and luminal progenitor cells utilizing xenotransplantation studies of preneoplastic mammary glands of EZH2+; neu and EZH2 wt; neu transgenic mice. METHODS: Generation of crossing EZH2+; neu and EZH2 wt; neu transgenic mice was described previously. Mouse handling and experimental procedures were conducted in accordance with the NIH Guide for the Care and Use of Laboratory Animals and were approved by the IACUC of the UM. Stem cells (Lin-/CD49f+/ESA-) and luminal progenitor cells (Lin-/CD49f+/ESA+) were isolated from the hyperplastic mammary glands of 8 weeks old EZH2+; neu and EZH2 wt; neu mice by flow cytometry (n=15 per group). Stem cells and luminal progenitor cells were injected into cleared fat pads of 3 weeks old FVB mice. After 5 weeks the mammary glands were subjected to flow cytometry and histology. RESULTS: Histologic study showed that only the stem cells, but not the luminal progenitor cells, extracted from EZH2+; neu and EZH2 wt; neu transgenic mice were able to form mammary outgrowths. Outgrowths of EZH2+;neu mice had significantly increased epithelial proliferation and increased numbers of terminal end buds (p<0.05) compared to EZH2 wt;neu outgrowths. EZH2 +;neu outgrowths had significant upregulation of Ki67 and pSTAT5 proteins. Flow cytometry of the outgrowths revealed that while all cell populations were increased, EZH2 induced a more pronounced expansion of the stem cell and luminal progenitor cell populations. CONCLUSIONS: Our data show that EZH2 overexpression in ErbB2 mice induces an expansion of the multipotent mammary stem cell population with the ability to regenerate the cellular heterogeneity of the mammary gland and develop hyperplastic outgrowths. We found that EZH2 promotes hyperproliferation and upregulation of STAT5 phosphorylation in the mammary epithelium in vivo.

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 5208. doi:1538-7445.AM2012-5208
Abstract 5214: Functional interaction between foxm1 and β-catenin
Authors: Gong Aihua , Yu Guanzhen , Zhang Nu , Wei Ping , Aldape Kenneth D. , Colman Howard , Xue Jianfei , Liu Mingguang , Sawaya Raymond , Xie Keping , Yung W.K. Alfred , Medema René H. , He Xi , Huang Suyun
Published: August 2012

The Wnt/β-catenin signaling pathway is aberrantly activated in human cancers and is critical for cancer formation, but its molecular mechanisms are not fully understood. In the current study, we found that FoxM1, which is also activated in most human tumors, is a novel downstream component of Wnt signaling and is critical for β-catenin transcriptional function in tumor cells. Wnt increases the level and nuclear translocation of FoxM1 through inhibition of FoxM1 protein degradation. FoxM1 binds directly to β-catenin and enhances β-catenin nuclear localization and transcriptional activity. Moreover, FoxM1, β-catenin and TCF-4 are mutually recruited to Wnt target-gene promoters, and FoxM1 promotes the assembly of the β-catenin-TCF transcription activation complex in the promoters hence the Wnt target gene expression. Furthermore, interaction of FoxM1 and β-catenin plays a critical role in glioma stem cell self-renewal and differentiation and is required for glioma formation. Finally, the expression levels of nuclear β-catenin in human GBM directly correlates with levels of nuclear FoxM1, supporting the critical role of FoxM1 in β-catenin activation in human GBM. Given the importance of FoxM1 and the Wnt/β-catenin signaling pathway in human cancers in general, our findings not only provide an improved understanding of the molecular mechanisms underlying Wnt/β-catenin activation and tumorigenesis but also suggest additional targets for therapeutic intervention.

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 5214. doi:1538-7445.AM2012-5214
Abstract 5215: EZH2-mediated STAT3 activation in glioblastoma
Authors: Kim Eunhee , Woo Dong-Hun , Lee Jeongwu
Published: August 2012

Glioblastoma multiforme (GBM) is the most common and lethal primary brain tumor despite maximal therapy. Recent studies suggest that GBMs contain highly tumorigenic, stem cell-like cells termed glioblastoma stem cells (GSCs). GSCs significantly contribute to tumor propagation and treatment resistance and thus are critical target for curative therapy in GBMs. These GSCs share a key characteristic of normal stem cells, such as unlimited self-renewal capacity. Maintenance of the stem cell status in normal stem cells is governed by the Polycomb Repressive Complex 2 (PRC2)-mediated transcriptional repression. Enhancer of zeste homolog 2 (EZH2) is the only catalytically active component in PRC2, and it methylates a specific lysine residue of histone 3, resulting in the repressive chromatin structure. Signal transducer and activator of transcription 3 (STAT3) regulates diverse cellular processes and is frequently activated during tumorigenesis. Components of PRC2 are highly expressed in various cancers including GBMs and STAT3 is required for GSCs maintenance. In this study, we investigated the functional interaction between these two oncogenic pathways regulating GSCs phenotype. We show that targeted pharmacologic disruption of EZH2 by the S-adenosylhomocysteine hydrolase inhibitor called 3-deazaneplanocin A (DZNep), or its specific downregulation by short hairpin RNA (shRNA) inhibits STAT3 activity. Furthermore, AKT-mediated EZH2 phosphorylation affects STAT3 activity through STAT3 methylation. We demonstrate that STAT3 bind to EZH2 promoter and inhibition of STAT3 activity by small molecule inhibitor decrease PRC2 protein expression. Targeting of EZH2 and STAT3 by combined treatment with DZNep and STAT3 inhibitor strongly impairs GSCs self-renewal in vitro and decreases markers of neural stem cell multipotency. In addition, shEZH2 transduction + STAT3 inhibitor treatment extend survival of SCID mice with intracranial GSCs than shEZH2 single transduced group. Together, these obtained results strongly suggest the presence of positive feedback activation loop between PRC2 and STAT3 signaling in GSCs and targeting of this activation loop may offer an attractive therapeutic strategy for GBM.

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 5215. doi:1538-7445.AM2012-5215