bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 718: Optical molecular imaging of HER1-positive cancer using near-infrared PEGylated indocyanine green-labeled panitumumab.
Authors: Zhou Yang , Kim Young-Seung , Milenic Diane E. , Baidoo Kwamena E. , Brechbiel Martin W.
Published: August 2014

Optical molecular imaging has attracted remarkable attention in recent years for cancer visualization and localization due to its characteristics of real-time, high sensitivity and specificity, cost-effectiveness and non-ionization. Indocyanine green (ICG) is the only clinically approved near-infrared fluorescent dye, and has been frequently employed to conjugate with antibodies or their fragments in the development of new cancer-targeted optical imaging agents. However, ICG molecules tend to form aggregates which cannot be removed by dialysis after antibody conjugation because of their high molecular weight. Previous data from our group has demonstrated that an amine-reactive PEGylated analogue of ICG (PEG-ICG) could successfully label an anti-HER1 antibody panitumumab with little aggregation compared with the non-PEGylated ICG. In this study, we present three higher equivalents (5×, 10×, and 20×) of PEG-ICG for panitumumab conjugation to yield ICG-PEG-panitumumab conjugates. Similar to previous studies, conjugation with PEG-ICG (5×) did not cause significant aggregates; whereas higher percentage of aggregates were observed for higher equivalents of PEG-ICG (∼10% and ∼20% for 10× and 20×, respectively). Collected PEG-ICG aggregates showed altered shape of absorbance spectra but not emission profile. In addition, the final molar ratios of ICG to panitumumab of the conjugates were 0.7, 2.3 and 6.0 for 5×, 10×, and 20×, respectively. Competitive radioimmunoassay demonstrated that the targeting moiety of the PEGylated bioconjugates was conserved. Fluorescence microscopy also demonstrated strong cellular binding and excellent fluorescent intensity of the bioconjugate (20×) in HER1-expressing A431 and SKOV3 cells. Comparatively, the conjugates with 5× and 10× PEG-ICG showed little or weaker fluorescent signal under the same exposure time. Hence, purified ICG-PEG-panitumumab bioconjugates are suitable candidates for the in vivo optical imaging of HER1-expressing tumors.

Citation Format: Yang Zhou, Young-Seung Kim, Diane E. Milenic, Kwamena E. Baidoo, Martin W. Brechbiel. Optical molecular imaging of HER1-positive cancer using near-infrared PEGylated indocyanine green-labeled panitumumab. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 718. doi:10.1158/1538-7445.AM2013-718
Abstract 719: Accumulation of amino acids in metastatic foci of human colon cancer xenografts revealed by newly developed method for imaging mass spectrometry of amino acids.
Authors: Toue Sakino , Sugiura Yuki , Kubo Akiko , Ohmura Mitsuyo , Karakawa Sachise , Mizukoshi Toshimi , Yoneda Junya , Miyano Hiroshi , Noguchi Yasushi , Kobayashi Tsuyoshi , Kabe Yasuaki , Suematsu Makoto
Published: August 2014

MALDI imaging mass spectrometry (IMS) provides information about the spatial distribution of metabolites within thin slices of tissue, and has been used to elucidate complex phenotypes under various physiological conditions. Previously, our group reported distinct spatial distribution of a variety of metabolites in experimental model of hepatic micrometastasis of the solid tumor. However the metabolic properties in tumor and host tissues are not fully characterized, because of difficulty in visualizing most amino acids, due to their lower ionization efficiency.

Here, by using of p-N,N,N-trimethylammonioanily N’-hydroxysuccinimidyl carbamate iodide (TAHS) as a derivatizing reagent, we have successfully developed the method for the detection of various amino acids simultaneously by MALDI-MS on tissue section. We prepared liver section from hepatic metastasis model of human colon cancer, and then performed MALDI-IMS. To compare the signal intensities of amino acids among the different sections, we normalized the MALDI-IMS data with the quantified value of each amino acid obtained from capillary electrophoresis-mass spectrometry. The result indicated the amount of glycine, phenylalanine, leucine, glutamate, and glutamine were significantly elevated in metastatic foci compared to liver parenchyma. Other metabolites such as ATP and glutathione also accumulated in metastatic foci, and these results suggested that increased amino acid pool were required to maintain ATP and GSH levels in tumor.

In conclusion, we have demonstrated that novel imaging technique by using of IMS combined with on-tissue TAHS derivatization enables the visualization of amino acid distribution in tissue. The current method could be powerful tool to elucidate the mechanism for metabolic changes of cancer disease in vivo.

Citation Format: Sakino Toue, Yuki Sugiura, Akiko Kubo, Mitsuyo Ohmura, Sachise Karakawa, Toshimi Mizukoshi, Junya Yoneda, Hiroshi Miyano, Yasushi Noguchi, Tsuyoshi Kobayashi, Yasuaki Kabe, Makoto Suematsu. Accumulation of amino acids in metastatic foci of human colon cancer xenografts revealed by newly developed method for imaging mass spectrometry of amino acids. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 719. doi:10.1158/1538-7445.AM2013-719
Abstract 720: A validation study on photoacoustics imaging of fluorescent pyroporphysome in vivo.
Authors: Lakshman Minalini , Bu James , Maeda Azusa , Zheng Gang , Needles Andrew , Theodoropoulos Catherine , Da Costa Ralph
Published: August 2014

Photoacoustics (PA) is a hybrid in vivo imaging modality that combines the temporal resolution of optics, and low acoustic scattering and high spatial resolution of micro-ultrasound. This innovation can discern optical absorption of endogenous and exogenous contrast agent(s) in the tumor micro-environment. This advancement is made possible by precise control of optical wavelength using a tunable pulsed laser, ranging from 680-970nm. In this study, we demonstrate fluorescent pyroporphysome, a nanoparticle, to be a photoacoustic contrast agent by which we can monitor its accumulation locally within the tumor.

Approach: Co-registered ultrasound (anatomical) and PA imaging of subcutaneous tumors was accomplished with a LZ250 21 MHz transducer on the Vevo® LAZR system (FUJIFILM VisualSonics, Inc.). Mammary tumors were generated by implanting from MDA-MB-231H2N cell line under the skin line. Pyroporphysomes (120 nm in size) were administered by tail vein at a dose of 300 nmoles. Multiwavelength photoacoustic scans were acquired and quantified over 24 hours using Vevo Spectro (FUJIFILM VisualSonics, Inc.), an ensuite absorbance spectrum quantification tool. Cri Maestro (Quorum Technologies, Inc.) was used for concurrent whole body fluorescence imaging.

Results: Multi-wavelength analyses identified an in vivo PA absorbance of 680 nm to pyroporphysome. Earliest detection was at 20 minutes post bolus in the tumor and PA signal for pyroporphysomes persisted at 24 h. Signal accumulation is supported by a 22 fold change in signal intensity per 3D volume (3.8% post bolus vs 87% at 24h). Fluorescence analyses validate this accumulation in the tumor. Taken together, photoacoustic imaging identifies pyroporphysome as a bimodal contrast agent. Additional evidence includes a shift in signal localization in the PA scans wherein pyroporphysomes were first detected at the tumor periphery (<1mm below the skin line), and as deep as 2mm towards the tumor core at 24 hours. In conclusion, data herein presents photoacoustic imaging as the next generation imaging modality for concurrent molecular and anatomical information to better understand mechanistic changes in the tumor microenvironment.

Citation Format: Minalini Lakshman, James Bu, Azusa Maeda, Gang Zheng, Andrew Needles, Catherine Theodoropoulos, Ralph Da Costa. A validation study on photoacoustics imaging of fluorescent pyroporphysome in vivo. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 720. doi:10.1158/1538-7445.AM2013-720
Abstract 74: Mitochondrial MKP1-mediated radioresistance in breast cancer stem cells.
Authors: Candas Demet , Chuang Frank , Fan Ming , Shen Rulong , Sweeney Colleen , Borowsky Alexander , Vaughan Andrew , Li Jian Jian
Published: August 2014

The overall cure rate of primary tumors has been significantly improved in the last three decades; however, metastatic and recurrent tumors with aggressive growth and therapy-resistance remain as the major factors shortening breast cancer patients’ survival. MKP1, a mitogen-activated protein kinase (MAPK) phosphatase, was shown to be linked with chemoresistance in breast cancer cells and was overexpressed in radioresistant breast cancer cells that survived long-term fractionated irradiation. Herein, we showed that MKP1 is present in the mitochondria and mitochondrial MKP1 levels are significantly enhanced in irradiated cells, suggesting that increased MKP1 translocation into the mitochondria may function to attenuate pro-apoptotic signals that were initiated from mitochondria-localized MAPK, c-Jun N-terminal kinase (JNK). We found that increased mitochondrial MKP1 levels correlated with the reduced level of phosphorylated active JNK in irradiated cells. Such mitochondrial MKP1-mediated dephosphorylation of JNK was predominantly enhanced in the radioresistant breast cancer cells that can be sensitized by siRNA-mediated inhibition of MKP1. Our results also demonstrated the involvement of extracellular regulated kinase (ERK) as the upstream signal for MKP1 mitochondrial translocation. The identification of cancer stem cells (CSCs) in all human tumors and their involvement in tumor radioresistance encouraged the studies investigating whether MKP1-mediated survival mechanism is present in radioresistant breast cancer cells. Here we showed that MKP1 is overexpressed in irradiated HER2-positive breast CSCs. These data provide critical insights on the aggressive phenotype of breast tumors and define novel diagnostic and therapeutic targets to re-sensitize resistant breast cancer stem cells.

Citation Format: Demet Candas, Frank Chuang, Ming Fan, Rulong Shen, Colleen Sweeney, Alexander Borowsky, Andrew Vaughan, Jian Jian Li. Mitochondrial MKP1-mediated radioresistance in breast cancer stem cells. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 74. doi:10.1158/1538-7445.AM2013-74
Abstract 748: Studying the significance of human p53-Sin3B interaction under the condition of DNA damage.
Authors: Kadamb Rama , Mittal Shilpi , Bansal Nidhi , Dwarakanath Bilikere Srinivasa Rao , Saluja Daman
Published: August 2014

Sin3, a global regulator of transcription plays an important role in mediating gene regulation, by binding to various transcription factors through its highly conserved Paired Amphipathic Helices (PAH) domains. Physical association of Sin3 corepressor molecule with human p53, a tumour suppressor protein is now well established. In response to stimuli that activate p53, cells can undergo repair processes, cell cycle arrest or apoptosis. In order to combat the stress, p53 gets activated by posttranslational stabilization and modulate the expression levels of its target genes. There are number of genes which are negatively regulated by p53, but the mechanism of repression is not well characterized. We hereby show that p53 interacts with Sin3/HDAC corepressor complex in-vivo and expression of Sin3B is up regulated in response to DNA damaging stimuli in p53 dependent manner. Increase in the levels of Sin3B upon different kind of DNA damage suggests that Sin3B might be an important protein involved in DNA damage pathway. Sin3/HDAC corepressor complex is recruited by p53 onto the promoters of its target genes, resulting in the down regulation of p53 target genes. In our study we propose that the mechanism of repression of p53 target genes is through recruitment of Sin3/HDAC corepressor complex which leads to context specific chromatin modification. Such modifications results in enrichment of epigenetic marks like H3K9me3, H3K27me3, which are marker of repression under condition of DNA damage induced by Bleomycin. Knockdown of Sin3B using shRNA causes derepression of p53 target genes, suggesting that Sin3B is a key player in p53 mediated transrepression. Based on our studies we propose that Sin3B is an important corepressor molecule recruited by p53 in response to DNA damage and Increased Sin3B expression is an early event in DNA damage induced by Bleomycin. We further provide evidence that p53 regulate its target genes, namely HSPA8, MAD1, CRYZ, ANLN and CDC25c through its interaction with Sin3/HDAC corepressor complex which leads to chromatin modification by recruiting proteins involved in epigenetic modifications.

Citation Format: Rama Kadamb, Shilpi Mittal, Nidhi Bansal, Bilikere Srinivasa Rao Dwarakanath, Daman Saluja. Studying the significance of human p53-Sin3B interaction under the condition of DNA damage. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 748. doi:10.1158/1538-7445.AM2013-748
Abstract 764: Transient up-regulation of Myc in B-cell lymphomas enhances p53-independent apoptotic responses to chemotherapy.
Authors: Sotillo-Piñeiro Elena , Thomas-Tikhonenko Andrei
Published: August 2014

The c-MYC oncogene deregulation is a common trait in human cancers, with programmed cell death (or apoptosis) among Myc-regulated events. Myc is well-known to induce apoptosis in a p53-dependent manner, via the Myc→ARF ┤MDM2 ┤p53 pathway. We had previously shown that this pathway couldbe exploited to increase sensitivity to anti-cancer drugs. Specifically, small increases in Myc levels obtained by inhibiting Myc-targeting microRNA-34a resulted in enhanced apoptotic response of B-cells to bortezomib (Sotillo et al, Oncogene 2010). Because many Myc-driven tumors are defective for p53 activity, we sought to determine whether transient up-regulation of Myc also increases cell death in response to chemotherapeutic drugs in a p53-deficient background. For this purpose, we used B-lymphoma cells isolated from bone marrows of p53ER™ knock-in mice and subsequently transduced with a Myc-expressing retrovirus (Amaravadi et al, J Clin Inv 2007, Yu et al, Blood 2007). This inducible system allowed us to distinguish between p53-dependent (cells treated with tamoxifen) and independent (no tamoxifen added) cell death. Additionally, instead of modulating Myc levels through miRNA inhibitors, which currently have limited clinical utility, we increased Myc stability with a small molecule inhibitor of GSK3β, which promotes proteosomal degradation of Myc. We observed that the activation of p53 via the addition of tamoxifen is sufficient to induce robust apoptosis, with neither modulation of Myc levels nor additional treatment with doxorubicin being necessary. On the other hand, in the absence of active p53 doxorubicin was needed to kill Myc/p53ER™ cells, but cell killing was rather inefficient. Remarkably, pharmacological stabilization of Myc strongly enhanced p53-independent doxorubicin-induced apoptosis. This enhancement was accompanied by selective activation of pro-apoptotic genes BIM, BAX and BAK, but not PUMA or NOXA, suggesting that the response was indeed p53-independent. To validate this effect in a more relevant setting, we inhibited GSK3β in various Burkitt's lymphoma cell lines and achieved consistent up-regulation of Myc. Most importantly, even in p53mut Ramos cells, Myc stabilization resulted in sharply increased responses to doxorubicin. Our results suggest that transient up-regulation of Myc could be a viable adjuvant therapy even for tumors with p53 loss or MDM2 amplification.

Citation Format: Elena Sotillo-Piñeiro, Andrei Thomas-Tikhonenko. Transient up-regulation of Myc in B-cell lymphomas enhances p53-independent apoptotic responses to chemotherapy. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 764. doi:10.1158/1538-7445.AM2013-764
Abstract 768: A role for c-Rel in ΔNp63α/v-RASHA-driven carcinogenesis?.
Authors: King Kathryn E. , Ponnamperuma Roshini M. , Park Sa Ra , Jay Steven , Ha Linan , Weinberg Wendy C.
Published: August 2014

The p63 isoform ΔNp63α is expressed in basal keratinocytes and overexpressed in human squamous cell carcinomas, but the mechanisms whereby this p53 homologue contributes to cancer pathogenesis have yet to be elucidated fully. In mimicking the overexpression of ΔNp63α observed in squamous cell carcinomas using transient adenoviral transduction of primary murine kerationcytes, we showed that overexpression of ΔNp63α inhibits Ca2+-mediated growth arrest and biochemical differentiation. We previously reported that this block in growth arrest is mediated via the NF-κB subunit, c-Rel, which accumulates in a phosphorylated form in the nucleus of ΔNp63α-overexpressing cells and physically associates in a phosphorylation-dependent manner with ΔNp63α. Consistent with the observed effects on growth regulation, ΔNp63α:c-Rel complexes bind to a p63 binding site on the cdk inhibitor p21WAF1. To explore the biological impact of long-term ΔNp63α overexpression in primary murine keratinocytes, lentiviruses were developed. Consistent with our transient adenoviral vector studies, keratinocytes expressing lenti-ΔNp63α have enhanced proliferation rates over 15 days in culture relative to lenti-GFP controls. Using a nude mouse grafting model that allows distinction between normal, benign, and malignant growths, we previously reported that lenti-GFP keratinocytes expressing oncogenic v-rasHa form well differentiated papillomas at the graft site, while keratinocytes expressing lenti-ΔNp63α in combination with v-rasHa form undifferentiated carcinomas. To expand this model system to study c-Rel we first confirmed that lentivirus-driven ΔNp63α overexpression results in sustained nuclear accumulation of the NF-kB subunit c-Rel, consistent with our observations using the adenovirally transduced cultures. In the lenti-ΔNp63α expressing cultures, enhancement of c-Rel is observed beginning at day 5 post-infection and is maintained through the latest time point tested, 14 days. Lentiviral c-Rel shRNAs have been developed to assess the contribution of altered nuclear c-Rel expression to ΔNp63α-mediated growth regulation in vitro and in vivo and have been successfully used to knockdown c-Rel to the latest time point tested, 28 days. Taken together, these data support a role for ΔNp63α in facilitating keratinocyte transformation and provide a model system for elucidating the contribution of NFkB/c-rel to ΔNp63α /v-rasHa-driven carcinogenesis.

Citation Format: Kathryn E. King, Roshini M. Ponnamperuma, Sa Ra Park, Steven Jay, Linan Ha, Wendy C. Weinberg. A role for c-Rel in ΔNp63α/v-RASHA-driven carcinogenesis?. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 768. doi:10.1158/1538-7445.AM2013-768
Abstract 770: Association of YAP expression with colorectal cancer progression.
Authors: Xie Daxing , Wang Xiangyang , Min Jiang , Li Xiaolan , Hu Jubo , Gong Jianping
Published: August 2014

YAP, a crucial transcriptional coactivator in the Hippo signaling pathway, is upregulated in several human tumors and suggested to promote tumor progression. However, its expression level and role in colorectal cancer (CRC) remain unknown. In this study, YAP expression and the correlation between YAP expression and CRC clinical features were investigated. Quantitative real-time polymerase chain reaction and Western blotting were performed on 30 matched pairs of fresh CRC tissues and adjacent normal mucosae from 30 CRC patients. Immunohistochemical analysis was performed on 116 matched pairs of paraffin-embedded CRC tissues and adjacent normal mucosae, as well as in 73 cases of metastatic lymph nodes. Our results showed YAP expression level in CRC or lymphatic metastatic tissues was clearly higher than that in normal mucosae (P<0.01), whereas that in CRC tissues with lymphatic metastasis was higher than that in tissues without lymphatic metastasis (P<0.05). YAP expression is associated with serosal invasion, lymphatic metastasis, lymph node ratio, remote metastasis, Dukes stage, and the carcinoembryonic antigen level (P<0.05). It is also an independent predictor of the survival of CRC patients (P<0.05). Patients with high YAP expression level exhibited lower overall survival rates than those with low expression (P=0.001). Further analysis showed that YAP predicted CRC prognosis primarily for patients with late-clinical-stage CRC (P=0.002). These findings suggest that YAP is a potential marker for predicting CRC progression and prognosis. YAP upregulation is associated with poor overall survival time in CRC patients, particularly in those with late stage of the disease. Therefore, YAP may be an effective therapeutic target for late-stage tumors.

Citation Format: Daxing Xie, Xiangyang Wang, Jiang Min, Xiaolan Li, Jubo Hu, Jianping Gong. Association of YAP expression with colorectal cancer progression. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 770. doi:10.1158/1538-7445.AM2013-770

Note: This abstract was not presented at the AACR Annual Meeting 2013 because the presenter was unable to attend.
Abstract 780: Knockdown of p53 increases tumorigenicity of human breast cancer cells.
Authors: Liu Fang , Roy Tanima , So Jae Young , Smolarek Amanda , Lu You-Rong , Suh Nanjoo
Published: August 2014

The tumor suppressor p53 is mutated or functionally inactivated in ∼ 70% cancer. p53 causes cell cycle arrest, cellular senescence, or induces apoptosis in response to stress. Although knockdown of p53 has been shown to increase tumorigenicity of human colon and lung cancer cells, it is not known whether knockdown of p53 in human breast cancer cells can indeed lead to increased tumorigenicity. We show that knockdown of p53 in human breast cancer cells significantly increases tumorigenicity in vivo and colony formation on soft agar in vitro. Our ongoing studies are elucidating the underlying mechanisms. To the best of our knowledge, this is the first study demonstrating that knockdown of p53 increases tumorigenicity of human breast cancer cells. Our results highlight the importance of the tumor suppressor p53 in human breast cancer.

Citation Format: Fang Liu, Tanima Roy, Jae Young So, Amanda Smolarek, You-Rong Lu, Nanjoo Suh. Knockdown of p53 increases tumorigenicity of human breast cancer cells. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 780. doi:10.1158/1538-7445.AM2013-780

Note: This abstract was not presented at the AACR Annual Meeting 2013 because the presenter was unable to attend.
Abstract 794: RNA-Seq and whole transcriptome analyses in ependymomas.
Authors: Costa Fabricio F. , Bischof Jared M. , Hamm Chris , Vanin Elio F. , Bonaldo Maria F. , Iannaccone Stephen , Rajaram Veena , Tomita Tadanori , Goldman Stewart , Soares Marcelo B.
Published: August 2014

Ependymoma is a common pediatric central nervous system (CNS) tumor that is believed to originate from ependymal cells located in the lining of ventricular surfaces in the brain. This type of pediatric tumor presents great challenges in treatment despite the advances in neurosurgical techniques and adjuvant therapy. In order to identify possible molecular markers that could improve clinical management and better treatment, we have used RNA-Seq to profile the transcriptome of ependymoma samples with different outcomes. In this study, the ABI SOLiD WT (Whole Transcriptome) technology was utilized to sequence three different ependymoma tumor samples and one normal control brain tissue (enriched for ependymal cells). Whole Transcriptome sequencing produced approximately 10-30 million reads per sample and an average of 30-40% were mapped to the human reference sequence (NCBI Build 36.1) using Novoalign software. After obtaining these mapped locations, Perl scripts were written to overlap these intervals with other annotations and Genespring was used to visualize the reads. Different protein-coding, non-coding and microRNA gene databases were searched for known genes and to calculate the RPKM (Reads Per Kilobase of transcript per Million mapped reads) for each clustered gene. Multiple gene lists were generated corresponding to different RPKM-based comparisons between tumor and control tissues, ultimately enabling the identification of protein-coding genes, non-coding RNAs and microRNAs that are differentially expressed in ependymomas. Protein interaction networks were then built with these genes using the software GeneGo (Thomson Reuters). Thirty genes that are present in these networks are being selected for validation of differential expression in a larger cohort by Real-Time PCR TaqMan customized arrays. In conclusion, we have been able to identify genes differentially expressed in ependymomas, some of which of potential clinical importance.

Financial Support: Ann & Robert H Lurie Children's Hospital of Chicago, The Falk Brain Tumor Foundation and The Maeve McNicholas Memorial Foundation.

[FF Costa, JM Bischof, and C Hamm contributed equally to this work.]

Citation Format: Fabricio F. Costa, Jared M. Bischof, Chris Hamm, Elio F. Vanin, Maria F. Bonaldo, Stephen Iannaccone, Veena Rajaram, Tadanori Tomita, Stewart Goldman, Marcelo B. Soares. RNA-Seq and whole transcriptome analyses in ependymomas. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 794. doi:10.1158/1538-7445.AM2013-794
Abstract 795: Transcriptome instability as a common characteristic of solid cancers.
Authors: Sveen Anita , Johannessen Bjarne , Teixeira Manuel R. , Lothe Ragnhild A. , Skotheim Rolf I.
Published: August 2014

Analogous to the genomic types of instability describing cancer genomes, we recently proposed transcriptome instability as a genome-wide, pre-mRNA splicing related characteristic of colorectal cancer (Sveen et al., Genome Medicine, 2011). Here, we explore transcriptome instability in several major solid cancer types.

We have analyzed exon microarray data from ten cancer datasets (555 samples; seven cancer types) and four normal tissue types (93 samples; paired samples from colonic mucosa, lung, prostate and the stomach) for variation in relative amounts of aberrant exon usage, based on alternative splicing scores calculated by the FIRMA algorithm. Most major solid cancer types (breast, cervical, colorectal (two datasets), lung, and prostate (two datasets) cancer) showed large variations in aberrant exon usage amounts among the samples, and these amounts were strongly associated with splicing factor expression levels. Thus, we consider these cancer types to exhibit transcriptome instability. Non-random associations with splicing factor (n = 280) expression levels were shown by separation of samples according to aberrant exon usage amounts upon unsupervised hierarchical clustering analyses, and by stronger correlations between aberrant exon usage amounts and splicing factor expression levels than expected by chance (compared with random gene sets and permutations of the aberrant exon usage amounts; P < 0.001).

In comparisons across healthy tissue types and paired cancer and normal datasets, we observed tissue- and cancer-specific patterns in splicing factor correlations. Interestingly, in comparisons across cancer types with transcriptome instability (but not across cancer datasets that did not show transcriptome instability; gastric cancer, a second lung cancer dataset, and neuroblastoma), the non-random associations between aberrant exon usage amounts and splicing factor expression remained intact, indicating a failure to adhere to tissue specificity. Thus, we consider transcriptome instability to be a common feature of most major solid cancer types, and this deviant splicing pattern is associated with splicing factor expression levels.

Citation Format: Anita Sveen, Bjarne Johannessen, Manuel R. Teixeira, Ragnhild A. Lothe, Rolf I. Skotheim. Transcriptome instability as a common characteristic of solid cancers. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 795. doi:10.1158/1538-7445.AM2013-795
Abstract 8: A role for lumican as a biomarker of disease progression in human prostate adenocarcinoma.
Authors: De Velasco Marco A. , Hatanaka Yuji , Kura Yurie , Ando Naomi , Fukushima Emiko , Yamamoto Yutaka , Shimizu Nobutaka , Nozawa Masahiro , Yoshimura Kazuhiro , Yoshikawa Kazuhiro , Nishio Kazuto , Uemura Hirotsugu
Published: August 2014

We previously identified altered lumican expression in prostate tumors from genetically modified mice. Lumican is a small leucine-rich extracellular matrix protein that has been shown to modulate cell migration and proliferation during embryonic development, and tissue repair. Expression and distinct glycosylation patterns of lumican in several tumor and stromal tissues has been shown to play important roles in vascular invasion, differentiation, proliferation, and invasion. To determine a possible role for lumican as a prognostic biomarker for prostate cancer, we examined protein expression in normal and tumor specimens from prostatectomy cases. Tissue microarrays were constructed and immunostained for lumican. Slides were digitized and the expression levels of lumican were scored in both the stroma and epithelia. Expression scores were compared with clinicopathological features and disease progression, defined as death or biochemical recurrence. Stromal Lumican expression in tumor was negatively associated with Gleason score, differentiation, node/metastasis status and disease progression. Progression free survival was significantly longer for patients with high expression of stromal lumican (HR=0.25; P=0.005). Based on this set, stromal expression of lumican correlated to good clinical outcome for patients with prostate cancer and thus appears to be a strong prognostic biomarker for disease progression.

Citation Format: Marco A. De Velasco, Yuji Hatanaka, Yurie Kura, Naomi Ando, Emiko Fukushima, Yutaka Yamamoto, Nobutaka Shimizu, Masahiro Nozawa, Kazuhiro Yoshimura, Kazuhiro Yoshikawa, Kazuto Nishio, Hirotsugu Uemura. A role for lumican as a biomarker of disease progression in human prostate adenocarcinoma. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 8. doi:10.1158/1538-7445.AM2013-8
Abstract 81: Rapamycin increases radiosensitivity of cancer cells by induction of premature senescence.
Authors: Nam Hae Yun , Han Myung Woul , Chang Hyo Won , Lee Yoon Sun , Lee Myungjin , Kim Mi Ra , Lee Hyang Ju , Jeoung Ji Yung , Moon So Young , Kim Hyo Jung , Kim Sang Yoon , Kim Seong Who
Published: August 2014

Autophagy is frequently activated in radioresistant cancer cells. Rapamycin, mammalian target of rapamycin (mTOR) inhibitor, activates autophagy but enhances radiosensitivity. The mechanism of these actions by which such opposing functions coexist was investigated on radiation-resistant cancer cell lines (AMC-HN-9 and U-87) and the antitumor activity was evaluated in mice bearing xenografts of the cancer cells. Enhanced autophagic flux induced by radiation returned to untreated control levels. Treatment of the cancer cells with rapamycin leads to the potentiation and prolongation of radiation-induced autophagy, the increases in senescence-associated β-galactosidase activity, heterochromatin formation, and irreversible growth arrest. Furthermore, rapamycine resulted in a tumor regrowth delay and increased the level of β-galactosidase staining and the expression of heterochromatin markers in irradiated xenografts. These results suggest that even though autophagy is a survival mechanism in radioresistant cells, a persistent activation of autophagy by mTOR inhibitor induces premature senescence in these cells, eventually making the cells radiosensitive. Our data suggest a novel mechanism by which an inhibition of mTOR pathway increases autophagy but paradoxically increases radiosensitivity in radioresistant cancer cells.

Citation Format: Hae Yun Nam, Myung Woul Han, Hyo Won Chang, Yoon Sun Lee, Myungjin Lee, Mi Ra Kim, Hyang Ju Lee, Ji Yung Jeoung, So Young Moon, Hyo Jung Kim, Sang Yoon Kim, Seong Who Kim. Rapamycin increases radiosensitivity of cancer cells by induction of premature senescence. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 81. doi:10.1158/1538-7445.AM2013-81
Abstract 827: Identification of the insulin-like growth factor 2 mRNA binding protein (IGF2BP1) as an important regulator of cIAP1 translation and apoptosis in rhabdomyosarcomas.
Authors: Faye Mame Daro , Graber Tyson , Langlois Stephanie , Cowan Kyle , Holcik Martin
Published: August 2014

Rhabdomyosarcoma, a neoplasm characterized by undifferentiated myoblats-like cells, is the most common soft tissue sarcoma of childhood and represents 3-4% of all childhood cancers. IGF2BP1 is an oncofetal protein that was first identified in the rhabdomyosarcoma RD cell line and was shown to be overexpressed in a variety of cancers. Our group has previously identified IGF2BP1 as a potential translation modulator of the cellular inhibitor of apoptosis protein 1 (cIAP1), a key regulator of the NFκB signaling pathway and of caspase-8 mediated cell death in mammalian cells. In this study, we report that IGF2BP1 and cIAP1 expression is upregulated in a panel of rhabdomyosarcoma cell lines. We also show that IGF2BP1 is a positive regulator of cIAP1 translation, specifically through an internal ribosome entry site (IRES) mechanism. Finally, we report that altering the levels of cIAP1 in two rhabdomyosarcoma cell lines, RH36 and RH41, either by IGF2BP1 knock-down or by a Smac mimetic coumpound, sensitizes these cells to TNFα-mediated cell death. Our results identify IGF2BP1 and cIAP1 as important regulators of apoptosis in rhabdomyosarcomas.

Citation Format: Mame Daro Faye, Tyson Graber, Stephanie Langlois, Kyle Cowan, Martin Holcik. Identification of the insulin-like growth factor 2 mRNA binding protein (IGF2BP1) as an important regulator of cIAP1 translation and apoptosis in rhabdomyosarcomas. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 827. doi:10.1158/1538-7445.AM2013-827
Abstract 847: PIAS3 induction of apoptosis is p53-independent and has STAT3-independent mediators.
Authors: Dabir Snehal , Liu Yu , Wildey Gary , Dowlati Afshin
Published: August 2014

Protein inhibitor of activated STAT3 (PIAS3) is an endogenous inhibitor of STAT3 that negatively regulates STAT3 transcriptional activity and cell growth and demonstrates limited expression in the majority of human squamous cell carcinomas of the lung. In the present study we sought to determine if PIAS3 inhibits cell growth in non-small cell lung cancer (NSCLC) cell lines by induction of apoptosis and further determine the dependence of PIAS3 activity on p53 status by using both wild-type and p53-null cells. Our results demonstrate that over-expression of PIAS3 promotes caspase 3 activation and PARP cleavage. Furthermore, the expression of pro-survival family members BclXL and Bcl-2 is decreased. These effects were observed after both transient and regulated expression of exogenous PIAS3 and were independent of p53 status. PIAS3 inhibition of STAT3 luciferase activity was also p53 independent. Microarray experiments were performed to further investigate the STAT3-dependence of PIAS3-induced apoptosis by comparing its gene expression signature with that of STAT3 siRNA treated cells. IPA pathway analysis showed that a number of genes related to cell death were significantly increased by PIAS3. Furthermore, a subset of apoptotic genes, including CIDEC and DAPK2, were uniquely expressed only after PIAS3 expression and not after STAT3 siRNA. Thus, PIAS3 may represent a promising lung cancer therapeutic target because of its p53-independent efficacy as well as its potential to synergize with direct STAT3 inhibitors.

Citation Format: Snehal Dabir, Yu Liu, Gary Wildey, Afshin Dowlati. PIAS3 induction of apoptosis is p53-independent and has STAT3-independent mediators. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 847. doi:10.1158/1538-7445.AM2013-847
Abstract 849: Reactive oxygen species mediated activation of AMP activated protein kinase and c-Jun N-terminal kinase plays a critical role in beta sitosterol induced apoptosis in multiple myeloma U266 cells.
Authors: Cho Sun-Mi , Kim Ji-Sung , song Hyosook , Sohn Eun-Jung , Kim Ji-Hyun , Jung Ji Hoon , Kim Jung-Hyo , Jeong Soo-Jin , Lee Eun-OK , Lee HyoJeong , Kim Sung Hoon
Published: August 2014

Although beta sitosterol has been well known to have anti-tumor activity in liver, lung, colon, stomach, breast and prostate cancers via cell cycle arrest and apoptosis induction, the underlying mechanism of anti-cancer effect of beta sitosterol in multiple myeloma cells was never elucidated until now. Thus, in the present study, the role of reactive oxygen species (ROS) in association with AMP-activated protein kinase (AMPK) and c-Jun N-terminal kinase (JNK) pathways was demonstrated in beta sitosterol treated multiple myeloma U266 cells. Beta sitosterol exerted cytotoxicity, increased sub-G1 apoptotic population and activated caspase-9 and -3, cleaved poly (ADP-ribose) polymerase (PARP) followed by decrease in mitochondrial potential in U266 cells. Beta sitosterol promoted ROS production, activated AMPK, acetyl-CoA carboxylase (ACC) and JNK in U266 cells. Also, beta sitosterol attenuated the phosphorylation of AKT, mammalian target of rapamycin (mTOR) and S6K, and the expression of cyclooxygenase (COX)2 and VEGF in U266 cells. Conversely, AMPK inhibitor compound C and JNK nhibitor SP600125 suppressed apoptosis induced by beta sitosterol in U266 cells. Furthermore, ROS scavenger N-acetyl-L-cysteine (NAC) attenuated beta sitosterol mediated sub-G1 accumulation, PARP cleavage, JNK and AMPK activation in U266 cells. Overall, these findings for the first time suggest that ROS mediated activation of cancer metabolism related genes such as AMPK and JNK plays an important role in beta sitosterol induced apoptosis in U266 multiple myeloma cells.

Citation Format: Sun-Mi Cho, Ji-Sung Kim, Hyosook song, Eun-Jung Sohn, Ji-Hyun Kim, Ji Hoon Jung, Jung-Hyo Kim, Soo-Jin Jeong, Eun-OK Lee, HyoJeong Lee, Sung Hoon Kim. Reactive oxygen species mediated activation of AMP activated protein kinase and c-Jun N-terminal kinase plays a critical role in beta sitosterol induced apoptosis in multiple myeloma U266 cells. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 849. doi:10.1158/1538-7445.AM2013-849
Abstract 861: Analysis of predictive genes in triple negative breast cancer in response to a gamma-secretase inhibitor.
Authors: Olsauskas-Kuprys Roma , Osipo Clodia
Published: August 2014

Defined by the lack of estrogen and progesterone receptors and amplification of human epidermal growth factor receptor-2 (HER-2), triple negative breast cancer (TNBC) is a devastating disease with no approved, targeted therapy to date. Characterized by aggressive behavior which includes high rates of metastasis and very poor prognosis, TNBC is presently treated with DNA-damaging agents such as cisplatin or carboplatin. The overall survival outcomes for women with TNBC is dismal and consequently TNBC research requires identification of biomarkers that specifically mediate signaling pathways that lead to disease progression and metastasis. Notch receptors which are necessary for self-renewal and survival of breast cancer stem cells are excellent candidate biomarkers to investigate in various subtypes of TNBC. Based on the critical need to identify predictive biomarkers, we hypothesized that inhibition of the Notch pathway via γ-secretase inhibition (GSI) will provide an effective blockade of TNBC growth in specific subtypes where predictive Notch gene expression profiles are significantly up or downregulated. A panel of three TNBC cell lines were used in this study: MDA-MB-231 (mesenchymal stem-like), MDA-MB-468 (basal-like 1), and BT549 (luminal). Using real-time PCR, Notch pathway-associated genes were measured which include Notch-1 and Notch-4 receptors, Notch target genes (i.e. Deltex-1, Hes-1, Hes-5, and Hey-1), and genes such as IL-8 and MMP-9 which are associated with aggressive tumor behavior. Both anchorage-dependent and anchorage-independent growth assays were measured in response to MRK-003 GSI, carboplatin, and the combination. We have identified for the first time a TNBC line (MDA-MB-468) that expressed the highest level of Hes-1, a Notch gene target, and is the most sensitive to single agent MRK-003 GSI treatment. We also identified that this cell line with the highest sensitivity to MRK-003 GSI upregulates Notch-4 and IL-8 in response to the GSI to a greater extent than either of the two other TNBC lines. Furthermore, the addition of carboplatin at its IC50 concentration significantly increased the sensitivity of MRK-003 GSI in otherwise insensitive TNBC lines. These results suggest for the first time that: 1) Hes-1 could potentially be a valuable predictive biomarker of Notch activity in TBNC; 2) induction of Notch-4 and/or IL-8 could predict response to MRK-003 GSI; and 3) carboplatin might provide a means to increase sensitivity to MRK-003 GSI in resistant TNBC.

Citation Format: Roma Olsauskas-Kuprys, Clodia Osipo. Analysis of predictive genes in triple negative breast cancer in response to a gamma-secretase inhibitor. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 861. doi:10.1158/1538-7445.AM2013-861
Abstract 869: PTEN/PI3K oncogenic pathway profiling informs an in vivo synergistic therapeutic model for basal-like breast cancer.
Authors: Saal Lao H. , She Qing-Bai , Gruvberger-Saal Sofia K. , Maurer Matthew , Jumppanen Mervi , Su Tao , Dendy Meaghan , Lau Ying-Ka I. , Memeo Lorenzo , Ringner Markus , Isola Jorma , Hibshoosh Hanina , Rosen Neal , Parsons Ramon
Published: August 2014

The basal-like breast cancer (BBC) subtype is generally characterized by positive staining for basal mammary epithelial cytokeratin markers, lack of hormone receptor and HER2 expression, and poor prognosis with currently no approved molecularly-targeted therapies. The oncogenic signaling pathways driving basal-like tumorigenesis, however, are not fully elucidated. In an analysis of phosphoinositide 3-kinase (PI3K) pathway-activating molecular aberrations in 116 unselected breast tumors, we find that three-quarters of cases had a potential oncogenic alteration to PIK3CA, PTEN, HER2, INPP4B, or EGFR, including 97% of estrogen receptor (ER)-negative tumors compared to 65% of ER-positive tumors (P<0.001). Interestingly, nearly all p53 mutant tumors had one or more of these alterations (93%, P=0.001). Loss of PTEN was significantly associated to EGFR overexpression, positivity for the BBC marker cytokeratin 5/14, and the BBC molecular subtype by mRNA gene expression profiling (all P<0.001), informing a potential therapeutic combination targeting the PTEN/PI3K and EGFR pathways in BBC. In BBC cell lines, combination treatment with the EGFR-inhibitor gefitinib plus PI3K-inhibitor LY294002 was synergistic and increased apoptosis. Similarly, in an in vivo BBC xenograft mouse model, gefitinib plus PI3K-inhibitor PWT-458 was more effective than either monotherapy. Our study supports the future clinical evaluation of EGFR and PI3K pathway inhibitors for the treatment of BBC.

Citation Format: Lao H. Saal, Qing-Bai She, Sofia K. Gruvberger-Saal, Matthew Maurer, Mervi Jumppanen, Tao Su, Meaghan Dendy, Ying-Ka I. Lau, Lorenzo Memeo, Markus Ringner, Jorma Isola, Hanina Hibshoosh, Neal Rosen, Ramon Parsons. PTEN/PI3K oncogenic pathway profiling informs an in vivo synergistic therapeutic model for basal-like breast cancer. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 869. doi:10.1158/1538-7445.AM2013-869
Abstract 886: OCT6 expression is associated with the resistance to cisplatin in lung cancer.
Authors: Kasai Daishi , Oguri Tetsuya , Uemura Takehiro , Hijikata Hisatoshi , Yokoyama Midori , Kunii Eiji , Takakuwa Osamu , Ohkubo Hirotsugu , Miyazaki Mikinori , Maeno Ken , Niimi Akio
Published: August 2014

Organic cation transporters (OCTs) of the solute carrier family 22 have been identified as uptake transporters for the charge state of a substrate such as cationic drugs. The OCTs have an isoform of OCT1, OCT2, OCT3, and OCT6. Previously OCT1-3 have shown to related with intracellular uptake of anticancer platinum drugs such as cisplatin (CDDP) and oxaliplatin; however an association of OCT6 and platinum drugs is not well elucidated. We found decreased gene and protein expressions of OCT6 in CDDP resistant PC14/CDDP cells compared to those in parental lung adenocaricinoma PC14 cells. In contrast, the expression levels of OCT1-3 were not changed between PC14 and PC-14/CDDP cells. The intracellular concentration of CDDP also decreased in PC14/CDDP compared with the parental cell. To elucidate the OCT6 for uptake of CDDP, we established a forced expression of OCT6 cell line by a transfection an OCT6 vector to PC14/CDDP cells. We found that intracellular CDDP concentration are increased concomitant with decreased resistance to CDDP in OCT6 overexpressed PC14/CDDP cells. These results indicate that OCT6 is related with uptake of CDDP, and that the expression of OCT6 could be one of the resistant factors against CDDP in lung cancer cells.

Citation Format: Daishi Kasai, Tetsuya Oguri, Takehiro Uemura, Hisatoshi Hijikata, Midori Yokoyama, Eiji Kunii, Osamu Takakuwa, Hirotsugu Ohkubo, Mikinori Miyazaki, Ken Maeno, Akio Niimi. OCT6 expression is associated with the resistance to cisplatin in lung cancer. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 886. doi:10.1158/1538-7445.AM2013-886