bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 70: Mouse models of human lung adenocarcinoma: Identification of potential tumor suppressors by functional in vivo shRNA screening
Authors: Yeddula Narayana , Xia Yifeng , Verma Inder
Published: May 2015

Lung cancer is one of the leading human cancer malignancies, and histopathologically divided into Non small cell lung cancer (NSCLC) and small cell lung cancer (SCLC). Lung adenocarcinoma is a major form of NSCLC. We have developed a lentiviral-vector-mediated mouse model, which enables generation of lung adenocarcinoma from less than 100 alveolar epithelial cells, and investigated the role of IKK2 and NF-κB in lung-cancer development. IKK2 depletion in tumour cells significantly attenuated tumour proliferation and significantly prolonged mouse survival. We identified Timp1, one of the NF-κB target genes, as a key mediator for tumour growth by activating ERK signaling pathway. Knockdown of either Ikbkb or Timp1 by short hairpin RNAs reduced tumour growth in both xenograft and lentiviral models. Further, by utilizing lentiviral mediated mouse models, we performed a genome wide in vivo shRNA screen to findout tumor suppressors or tumor suppressor like genes that will cooperate with KRasG12D expression. The screen identified several novel molecules as potential tumor suppressor properties, which will cooperate with KRasG12D. Several of these molecules were also altered in human patient cohorts of The Cancer Genome Atlas. Ephrin receptor A2, EphA2, is one of the molecule knockdown of which cooperated with KRasG12D expression to generate lung adenocarcinomas comparable to knockdown of potent tumorsuppressor P53 thus validating our screen. The mechanisms underlying EPhA2 mediated tumorsuppression are being studied. Overall, our study identified novel potential tumorsuppressors.

Citation Format: Narayana Yeddula, Yifeng Xia, Inder Verma. Mouse models of human lung adenocarcinoma: Identification of potential tumor suppressors by functional in vivo shRNA screening. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 70. doi:10.1158/1538-7445.AM2014-70
Abstract 701: In vivo anti-metastatic effects of uPAR retargeted oncolytic measles virus
Authors: Jing Yuqi , Zaias Julia , Merchan Jaime
Published: May 2015

The urokinase receptor (uPAR) is a clinically relevant target for novel biological therapies. Here, we investigated the antimetastatic effects of oncolytic measles virus retargeting uPAR (MV-uPA) in breast cancer metastases models. Species specificities of recombinant viruses retargeted against human (MV-h-uPA) or mouse uPA (MV-m-uPA) were demonstrated in vitro in human and murine breast cancer cell lines. MV-h-uPA and MV-m-uPA induced in vitro cytotoxicity and replicated in human breast cancer cells (MDA-MB231, MDA-MB436 and MCF-7) and murine mammary cancer cells (4T1), respectively. A syngeneic model of mammary cancer metastases was established by intravenous injection of 4T1 cells (5x10e4 per mouse) expressing highly efficient firefly luciferase into immunocompetent BALB/C mice. Seven days after tumor cell inoculation, MV-m-uPA or vehicle was administered into tumor-bearing mice via the tail vein (virus dose: 1×10e6 TCID50 per injection, three injections, every other day). Metastases progression was assessed by bioluminescence analysis. In this highly aggressive syngeneic model, MV-m-uPA treatment was associated with delay in metastases progression and improvement in survival, compared to controls. These effects were associated with detection of viable viral particles from lungs of mice treated with MV-m-uPA, as well as detection of MV-N staining in lung samples in tumor bearing treated mice. Finally, we validated the above effects in a model of human breast cancer metastases. This model was established by injection of 1×10e6 MDA-MB231-luc2 cells via tail vein into female nude mice. Ten days after tumor cell injection, mice were treated with three IV injections (every other day) of PBS or MV-h-uPA (1×10e6 TCID50). Metastases progression (by bioluminescence evaluation) was markedly inhibited in treated mice, compared to controls, resulting in improvement in survival. In conclusion, systemic administration of MV-uPA is effective in the treatment of breast cancer metastases in immune-competent and immune-deficient model, suggesting that measles virus mediated virotherapy may present a novel and promising strategy for treatment against metastatic breast cancer.

Citation Format: Yuqi Jing, Julia Zaias, Jaime Merchan. In vivo anti-metastatic effects of uPAR retargeted oncolytic measles virus. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 701. doi:10.1158/1538-7445.AM2014-701
Abstract 705: In vivo audition of tumor homing peptides using high-throughput sequencing and q-PCR
Authors: Toome Kadri , Mölder Tarmo , Kõiv Kuldar , Säälik Pille , Sugahara Kazuki N. , Ruoslahti Erkki , Teesalu Tambet
Published: May 2015

In vivo peptide phage display has been widely used to explore tumor vascular heterogeneity and to develop targeting ligands for the delivery of anticancer drugs and imaging agents. Numerous tumor homing peptides with various targeting specificities have been identified. To select a suitable targeting ligand for a particular tumor from an existing peptide panel, it is crucial to perform unbiased quantitative assessment of in vivo peptide homing.

Here we describe an approach for parallel evaluation of in vivo tumor homing of peptide-displaying phage clones. Mice bearing orthotopic xenografts of gliomas, breast tumors, and prostate tumors were intravenously injected with equimolar mix of phage clones displaying 12 different tumor homing or control peptides. After 30 min circulation and removal of blood by perfusion, representation of each phage clone in tumors and control organs was determined by high throughput sequencing (HTS) and quantitative PCR (qPCR). The ratiometric analysis demonstrated a clear and reproducible homing signature for each tumor model. Calibrated copy number data obtained by qPCR correlated well with the HTS analysis. Selected phage clones were validated for tumor homing by conventional single-phage homing studies using immunofluorescence, phage titration, and qPCR.

Our study shows that the ratiometric in vivo phage biodistribution analysis can be used to rapidly identify peptides that efficiently deliver payloads to particular tumor types. As the peptides are evaluated side-by-side in a same animal, inter-animal variability is eliminated and the number of animals required is dramatically decreased.

The choice of analysis (HTS vs qPCR) depends on the complexity of phage pool to be audited. HTS enables the analysis of highly complex phage pools, but introduces a potential bias owing to multiple DNA amplification steps. On the other hand, qPCR allows precise quantification of the copy number of the target sequences, and is suitable for low complexity pools. Narrowing down a complex pool with HTS followed by precise evaluation with qPCR can be a potential combination of the two analytical methods.

Citation Format: Kadri Toome, Tarmo Mölder, Kuldar Kõiv, Pille Säälik, Kazuki N. Sugahara, Erkki Ruoslahti, Tambet Teesalu. In vivo audition of tumor homing peptides using high-throughput sequencing and q-PCR. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 705. doi:10.1158/1538-7445.AM2014-705
Abstract 706: A novel photodynamic therapy with virus-mediated delivery of photosensitive cytotoxic fluorescent protein KillerRed for human cancers
Authors: Takehara Kiyoto , Tazawa Hiroshi , Hashimoto Yuuri , Kishimoto Hiroyuki , Fujiwara Toshiyoshi , Narii Nobuhiro , Mizuguchi Hiroyuki
Published: May 2015

Photodynamic therapy (PDT) is an antitumor strategy to induce tumor-specific cytotoxicity through accumulation of photosensitizers (PSs) and following light irradiation. Specific wavelength light irradiation induces the PS-mediated generation of reactive oxygen species (ROS) and subsequent cytotoxicity in tumor cells. Currently, some kinds of PSs, such as photofrin and laserphyrin, are used for PDT on clinical settings. However, the lack of sufficient and continuous accumulation of PSs in tumor tissues makes difficult to eradicate tumor cells by PDT. Therefore, the development of novel strategy for accumulation of PS in tumor tissues more efficiently and persistently is required to improve the antitumor effect of PDT. A bioengineered fluorescent protein KillerRed has been previously reported to generate ROS upon green light irradiation, suggesting a potential of KillerRed fluorescent protein as a novel PS. We recently confirmed that transient or stable transfection with KillerRed-expressing plasmid vector suppressed the cell viability through induction of ROS-mediated apoptosis in various types of human cancer cells when combined with light irradiation. In this study, we generated non-replicative adenovirus expressing KillerRed (Ad-KillerRed) and telomerase-specific conditionally replicating adenovirus expressing KillerRed (CRAd-KillerRed) to induce efficient accumulation of KillerRed in tumor cells. The in vitro antitumor effect of these viruses was investigated in human cancer H1299, HCT116 and HT29 cells in combination with light irradiation. Ad-KillerRed at high dose suppressed cell viability of human cancer cells when combined with light irradiation. In contrast, CRAd-KillerRed suppressed cell viability of human cancer cells more efficiently compared to Ad-KillerRed in combination with light irradiation. These results suggest that virus-mediated delivery system of KillerRed is a promising strategy for novel PDT. Now, in vivo experiments are under way to investigate antitumor effect of these viruses.

Citation Format: Kiyoto Takehara, Hiroshi Tazawa, Yuuri Hashimoto, Hiroyuki Kishimoto, Toshiyoshi Fujiwara, Nobuhiro Narii, Hiroyuki Mizuguchi. A novel photodynamic therapy with virus-mediated delivery of photosensitive cytotoxic fluorescent protein KillerRed for human cancers. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 706. doi:10.1158/1538-7445.AM2014-706
Abstract 708: Toca 511 gene therapy in combination with 5-fluorocytosine for intratumoral production of 5-fluorouracil in a colon cancer metastasis model
Authors: Rodriguez-Aguirre Maria E. , Espinoza Fernando Lopez , Martin Bryan , Yadiz Kader , Huang Tiffany T. , Ibanez Carlos E. , Ostertag Derek G. , Kasahara Noriyuki , Gruber Harry E. , Jolly Douglas J. , Robbins Joan M.
Published: May 2015

Despite advances in screening, colorectal cancer (CRC) remains the fourth most commonly diagnosed cancer and the second leading cause of cancer death for both men and women in the US. Approximately one half of patients with CRC develop liver metastases (mCRC). The standard treatment for mCRC is 5-fluorouracil (5-FU) based combination chemotherapy. 5-FU combination chemotherapy has extended the median survival of these patients from 6 to >20 months.

We are pursuing a unique investigational approach to treat cancer via intratumoral production of 5-FU. Patients are first administered Toca 511 (vocimagene amiretrorepvec), a retroviral replicating vector (RRV) which selectively replicates and spreads in malignant cells and encodes an optimized yeast cytosine deaminase (CD) gene. In infected cells, the CD enzyme is expressed and converts 5-FC (flucytosine, an orally available anti-fungal drug) to the anti-cancer drug 5-FU in situ.

The combination of Toca 511 with oral extended release 5-FC (Toca FC) is currently in clinical trials for recurrent High Grade Glioma (NCT01156584, NCT01470794, and NCT01985256). We tested the suitability of this approach for the treatment of mCRC in a mouse syngeneic liver metastasis model. CT-26-luciferase colon carcinoma cells were delivered via intrasplenic injection producing multiple tumor foci within the liver. Toca 511 was then delivered either by intrasplenic or intravenous injection followed by courses of 5-FC. Vector delivery to tumor was monitored by PCR. 5-FC and 5-FU were detected using LC/MS. The effect of treatment with Toca 511 and 5-FC in this mouse model of mCRC will be presented.

Citation Format: Maria E. Rodriguez-Aguirre, Fernando Lopez Espinoza, Bryan Martin, Kader Yadiz, Tiffany T. Huang, Carlos E. Ibanez, Derek G. Ostertag, Noriyuki Kasahara, Harry E. Gruber, Douglas J. Jolly, Joan M. Robbins. Toca 511 gene therapy in combination with 5-fluorocytosine for intratumoral production of 5-fluorouracil in a colon cancer metastasis model. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 708. doi:10.1158/1538-7445.AM2014-708
Abstract 709: Efficacy of Salmonella typhimurium A1-R on experimental breast cancer brain metastasis
Authors: Zhang Yong , Miwa Shinji , Zhang Nan , Hoffman Robert M. , Zhao Ming
Published: May 2015

The aim of this study was to evaluate the efficacy of Salmonella typhimurium A1-R (A1-R) on breast cancer brain metastases. High brain-metastatic variants of murine 4T1 breast cancer cells expressing red fluorescent protein (RFP) were injected into the left ventricle of transgenic nude mice expressing nestin-driven green fluorescent protein (ND-GFP). ND-GFP mice express GFP in nascent blood vessels. At various time points, the tumors and vasculature in the brain were imaged by laser-scanning confocal and stereo fluorescence microscopy. Eighty percent of the cells that reached the brain extravasated and grew perivascularly; twenty percent of the cells, however, proliferated within the vasculature which may lead to thrombosis-like infarction of the brain parenchyma. Compared to the control group, mice treated with Salmonella typhimurium A1-R (A1-R) had significant inhibition of brain metastasis and increased survival (p<0.05). The results of the present study suggest the clinical potential of bacterial therapy of breast cancer brain metastasis.

Citation Format: Yong Zhang, Shinji Miwa, Nan Zhang, Robert M. Hoffman, Ming Zhao. Efficacy of Salmonella typhimurium A1-R on experimental breast cancer brain metastasis. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 709. doi:10.1158/1538-7445.AM2014-709
Abstract 711: Salmonella typhimurium A1-R induces quiescent FUCCI-expressing cancer cells to cycle and become chemosensitive
Authors: Yano Shuya , Zhang Yong , Zhao Ming , Hiroshima Yukihiko , Miwa Shinji , Uehara Fuminari , Kishimoto Hiroyuki , Tazawa Hiroshi , Fujiwara Toshiyoshi , Hoffman Robert M.
Published: May 2015

Quiescent cancer cells are resistant to cytotoxic agents which target only proliferating cancer cells. Time-lapse imaging showed that Salmonella typhimurium A1-R (A1-R) encircled and invaded quiescent cancer cells in monolayer culture, thereby eliminating them. Moreover A1-R infected and killed quiescent fluorescent ubiquitination-based cell cycle indicator (FUCCI)-expressing cancer cells in tumor spheres. In contrast, cytotoxic agents did not kill quiescent cancer cells in tumor spheres. A1-R infection of FUCCI-expressing subcutaneous tumors growing in nude mice resulted in killing quiescent cancer cells resistant to cytotoxic agents. Furthermore, the combination of A1-R and cisplatin reduced tumor size compared with A1-R monotherapy or cisplatin alone. This study demonstrates that A1-R can kill quiescent cancer cells and also sensitize them to conventional chemotherapy. These results suggest a new therapeutic paradigm potentially more effective than current therapeutics which are ineffective against quiescent cancer cells.

Citation Format: Shuya Yano, Yong Zhang, Ming Zhao, Yukihiko Hiroshima, Shinji Miwa, Fuminari Uehara, Hiroyuki Kishimoto, Hiroshi Tazawa, Toshiyoshi Fujiwara, Robert M. Hoffman. Salmonella typhimurium A1-R induces quiescent FUCCI-expressing cancer cells to cycle and become chemosensitive. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 711. doi:10.1158/1538-7445.AM2014-711
Abstract 712: Salmonella typhimurium A1-R inhibits surgically induced breast cancer metastasis
Authors: Zhang Yong , Zhang Nan , Hoffman Robert M. , Zhao Ming
Published: May 2015

We investigated the efficacy of tumor-targeting Salmonella typhimurium A1-R in the perioperative period to eradicate micrometastatic disease. Fifty female BALB/c mice were inoculated in the mammary fat pad with metastatic murine mammary adenocarcinoma (4T1-RFP (3×105/mouse), and divided into five groups. Control group (n = 10) with no treatment; surgery group (n = 10) in which the tumor was completely resected at day 21 after cell inoculation; Salmonella typhimurium A1-R (A1-R) (n = 10) in which the primary tumor was treated with A1-R alone at day 10 after cell inoculation; postoperative-administration of A1-R (n = 10) in which A1-R was administrated only after the primary tumor was resected; perioperative administration of A1-R (n = 10) in which A1-R was administrated before and after the primary tumor was resected. Metastatic tumor burden was assessed by quantitative fluorescence imaging of metastasis. Efficacy was assessed by metastatic burden and survival. The study showed that excision of the primary tumor was associated with increased systemic metastatic burden, and postoperative metastases exhibited increased proliferation (p < 0.05). A1-R alone treatment inhibited metastasis compared to untreated control and surgery only (p<0.05). Post-operative A1-R treatment significantly inhabited surgically-induced metastases (p0.05). Perioperative administration of A1-R showed the best efficacy compared to all other treatments in inhibiting surgery-induced metastasis (p<0.05) and prolonged survival (p<0.05).

Citation Format: Yong Zhang, Nan Zhang, Robert M. Hoffman, Ming Zhao. Salmonella typhimurium A1-R inhibits surgically induced breast cancer metastasis. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 712. doi:10.1158/1538-7445.AM2014-712
Abstract 717: Novel potent antisense oligonucleotides targeting transforming growth factor beta1 (TGF-β1)
Authors: Jaschinski Frank , Korhonen Hanna , Braun Stephan , Wosikowski Katja , Janicot Michel
Published: May 2015

Transforming growth factor beta (TGF-β) is a key member of a large family of cytokines, which play critical, pleiotropic roles in the pathophysiology of various human diseases, such as cancer, inflammation, autoimmune disease, and cirrhosis/fibrosis. TGF-β1, -2 and -3 isoforms are cytokines encoded by different genes but sharing strong sequence and structure homology. They function as the primary mediators of TGF-β signaling via both non-canonical and canonical signaling pathways. In Oncology, TGF-β isoforms are associated with a wide range of biological processes such as tumor cell invasion and migration, angiogenesis, immunosuppression, as well as regulation of tumor stem cell properties. Hence, blocking the TGF-β signaling pathway may have a multifold therapeutic benefit in Oncology, although therapeutic relevance of the respective TGF-β isoforms remains poorly documented.

In order to evaluate the specific biological relevance of TGF-β1 isoform in cancer, we have initiated an extensive discovery program for identification of antisense oligodeoxynucleotide constructs selectively inhibiting expression of the TGF-β1 ligand. Based on the sequence of the human TGF-β1 mRNA, more than 150 Locked Nucleic Acid (LNA)-modified gapmers were designed, synthesized and tested in cell-based assays. Highly potent and selective TGF-β1 constructs were identified and selected based on efficient suppression of TGF-β1 mRNA/protein expression in different human and rodent tumor cell lines, and in human Peripheral Blood Mononuclear Cells (PBMCs). Effective target downregulation was demonstrated after lipofectamine aided-transfection (sub-nM concentration range), but also in the absence of any transfection agent (gymnotic delivery) at sub-µM concentrations. Selected TGF-β1 specific oligonucleotides were further tested in relevant animal xenograft models and strong target inhibition was also observed following systemic administration. Further details of this discovery program will be discussed and pharmacology properties and features of potent and selective TGF-β1 antagonists will be presented.

Citation Format: Frank Jaschinski, Hanna Korhonen, Stephan Braun, Katja Wosikowski, Michel Janicot. Novel potent antisense oligonucleotides targeting transforming growth factor beta1 (TGF-β1). [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 717. doi:10.1158/1538-7445.AM2014-717
Abstract 718: Systemic delivery of therapeutic siRNA by multifunctional mesoporous silica-based nanocarrier inhibits lung cancer growth and metastasis
Authors: Chen Yijie , Gu Hongchen , Xia Weiliang
Published: May 2015

RNAi-based therapy by targeting dysregulated genes has shown great promise in biomedical research but still newer versions of effective and safe delivery systems are required. In this study, we developed a novel siRNA delivery vector based on our magnetic mesoporous silica nanoparticles (M-MSNs) platform. This nanocarrier was constructed by loading siRNAs into the mesopores of M-MSNs, followed by polyethylenimine (PEI) capping, PEGylation and fusogenic peptide KALA modification. The resultant functionalized delivery system exhibited prolonged half-life in bloodstream, enhanced cell membrane translocation and endosomal escapablity, and favorable tissue biocompatibility and biosafety. Systemic application of vascular endothelial growth factor (VEGF) siRNA via this nanocarrier resulted in remarkable tumor suppression, both in subdermal and orthotopic lung cancer models, while tumor metastasis was also significantly reduced, overall leading to improved survival. In addition, the magnetic core of the particles and the functionalized fluorescence markers conveniently enabled in vivo imaging of target tissues. Taken together, this M-MSNs-based siRNA delivery vehicle has shown very favorable applicability for cancer therapy.

Citation Format: Yijie Chen, Hongchen Gu, Weiliang Xia. Systemic delivery of therapeutic siRNA by multifunctional mesoporous silica-based nanocarrier inhibits lung cancer growth and metastasis. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 718. doi:10.1158/1538-7445.AM2014-718
Abstract 719: Development of systemically-deliverable telomerase-specific oncolytic adenovirus
Authors: Aoyama Katsuyuki , Kuroda Shinji , Tazawa Hiroshi , Kagawa Shunsuke , Fujiwara Toshiyoshi
Published: May 2015

Background: Oncolytic virotherapy is an emerging treatment strategy that allows to destroy cancer tissues only but not normal tissues. We previously developed a telomerase-specific oncolytic adenovirus (Telomelysin) whose replication is controlled by the human telomerase reverse tran¬scriptase (hTERT) promoter, and the clinical safety and pharmacokinetics of Telomelysin has been already evaluated in the phase I clinical trial conducted in the US. While oncolytic adenoviruses can produce promising treatment efficacy, their application is basically limited to locoregional administration because of nonspecific trapping in the liver and neutralization by immune response after systemic delivery. Nano-sized materials have been identified as effective and attractive drug carriers in the fields of cancer treatment and diagnosis. Liposome is one of the most popular and widely-used drug carriers. In this study, we investigated the possibility of systemic delivery of telomerase-specific oncolytic adenoviral plasmid DNA via lipid encapsulation as an alternative approach to overcome the shortcomings of oncolytic adenovirotherapy.

Methods: TelomeScan, a modified Telomelysin expressing the green fluorescence protein (GFP), is used in this study. Cytotoxic activity of TelomeScan plasmid DNAs encapsulated by liposomes (Lipo-TelomeScan-pDNA) against various types of human cancer cell lines including HCT 116, a human colorectal carcinoma cell line, and MKN1, a human gastric carcinoma cell line, were evaluated by XTT assay and compared with liposome complexes of GFP plasmid DNA controlled by the cytomegalovirus (CMV) promoter (Lipo-GFP-pDNA) as a control agent.

Results: Freeze-thaw procedure proved that viable oncolytic adenoviruses were successfully produced in H1299, a human lung cancer cell line, after Lipo-TelomeScan-pDNA transfection. Lipo-TelomeScan-pDNA showed cytotoxic activity on various types of cancer cell lines. Lipo-TelomeScan-pDNA killed HCT116 and MKN1 cells in a dose-dependent manner and produced more effective cytotoxic activity than Lipo-GFP-pDNA.

Conclusions: Lipo-TelomeScan-pDNA proved potent cytotoxic effects on cancer cells by producing viable oncolytic adenoviruses. In vivo examination is needed for the next step.

Citation Format: Katsuyuki Aoyama, Shinji Kuroda, Hiroshi Tazawa, Shunsuke Kagawa, Toshiyoshi Fujiwara. Development of systemically-deliverable telomerase-specific oncolytic adenovirus. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 719. doi:10.1158/1538-7445.AM2014-719
Abstract 74: Activation of Akt1 accelerates carcinogen-induced tumorigenesis in mammary gland of virgin and post-lactating transgenic mice
Authors: Wu Yanyuan , Kim Juri , Elshimali Yayha , Vadgama Jaydutt V.
Published: May 2015

Introduction The data from in vivo and in vitro studies suggest that activation of Akt regulates cell survival signaling and plays a key role in tumorigenesis. To explore oncogenic role of Akt1 in the development of mammary tumor, transgenic mice were created. Methods The transgenic mice were generated by expressing myristoylated-Akt1 (myr-Akt1) under the control of MMTV-LTR promoter. The carcinogen 7, 12 dimethyl-1,2-benzanthracene (DMBA) was used for inducing tumor formation. Results The MMTV driven myr-Akt1 transgene expression was detected primarily in mammary glands, uterus, and ovaries and the expression level increased significantly in lactating mice, suggesting the response was hormone dependent. The total expression level of Akt in the mammary gland was also high in these lactating mice. Interestingly, the expression of MMTVmyr-Akt1 in ovary of transgenic mice caused significant increase in circulating estrogen levels, even at post-lactating stage. Expression of myr-Akt1 in mammary glands alone did not increase tumor formation frequency. However, an increased susceptibility to the induction of mammary tumors by DMBA was observed in transgenic mice, especially in post-lactating mice. DMBA induced 42.9% of mammary tumors in post-lactating transgenic mice within 34 weeks, but none in post-lactating wild-type mice. The myr-Akt1 driven mammary tumors induced by DMBA had increased phosphorylated-Akt1 and showed strong expression of estrogen receptor (ERα) and EGFR. Cyclin D1 was more frequently up-regulated in mammary tumors from transgenic mice compared to tumors from wild-type mice. Overexpression of Cyclin D1, however, was not completely dependent on activated Akt1. Interestingly, mammary tumors that had metastasized to secondary sites had increased expression of twist and slug, but showed low expression of Cyclin D1. Conclusions In summary, activation of Akt1 in mammary gland accelerated carcinogen-induced tumorigenesis, especially in post-lactating mice.

Citation Format: Yanyuan Wu, Juri Kim, Yayha Elshimali, Jaydutt V. Vadgama. Activation of Akt1 accelerates carcinogen-induced tumorigenesis in mammary gland of virgin and post-lactating transgenic mice. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 74. doi:10.1158/1538-7445.AM2014-74
Abstract 740: Phenotypic profiling and selectivity optimization of ERK inhibitors using a high-throughput imaged-based cell cycle assay
Authors: Chan Grace Ka-Yan , Kleinheinz Tracy , Martinson Matthew , Cheung Hok-Sum , Moffat John G.
Published: May 2015

The extracellular-signal-regulated kinases (ERK-1 and ERK-2) represent an essential node within the RAS/RAF/MEK/ERK signaling cascade that is commonly activated due to oncogenic mutations in RAF or RAS or due to upstream oncogenic signaling, such as through receptor tyrosine kinase (RTK) signaling. We have discovered and developed potent and selective small molecule inhibitors of both ERK-1 and 2. Optimization of kinase selectivity was a critical goal in order for ATP-competitive ERK inhibitors to maintain parity with the safety profile of highly selective allosteric MEK inhibitors. As a complement to enzymatic kinase panel profiling, we employed an imaged-based cell cycle assay, based on the expected on-target phenotype of cytostatic G1 arrest in B-Raf-mutant cell lines. We were thus able to simultaneously measure on-target and off-target activities. Inhibition of Cdk2, one of the primary off-targets, was associated with a distinct G2 cell cycle arrest, which enabled us to quantify the functional selectivity margin between ERK and Cdk2 in a single assay, and select ERK inhibitors with acceptable selectivity margins for further development.

Note: This abstract was not presented at the meeting.

Citation Format: Grace Ka-Yan Chan, Tracy Kleinheinz, Matthew Martinson, Hok-Sum Cheung, John G. Moffat. Phenotypic profiling and selectivity optimization of ERK inhibitors using a high-throughput imaged-based cell cycle assay. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 740. doi:10.1158/1538-7445.AM2014-740
Abstract 744: Effective use of MDK/Midkine and MEK inhibitor to treat KRas mutated pulmonary adenocarcinoma cells
Authors: Fukazawa Takuya , Maeda Yutaka , Ishida Naomasa , Yamatsuji Tomoki , Takaoka Munenori , Haisa Minoru , Takigawa Nagio , Whitsett Jeffery , Naomoto Yoshio
Published: May 2015

Lung cancer is the leading cause of cancer-related mortality worldwide. Although a platinum-doublet regimen has become the standard of care, the benefit is modest and the 5-year survival rate has remained essentially unchanged over the past 3 decades. Recently, several molecular alterations have been defined as “driver mutations,“ such as mutations in epidermal growth factor receptor (EGFR), KRas, chimeric tyrosine kinases involving ALK, RET, ROS1. And molecular targeting therapies for lung adenocarcinoma, targeting mutant EGFR or ALK, RET and ROS1 fusions, limit non-tumor toxicity and extend survival time compared to the conventional chemotherapies. However, there is no effective molecularly targeted therapy for mutant KRas-driven lung adenocarcinoma, the most frequent type of lung adenocarcinoma in the Caucasian population. Therefore, specific therapies that target various lung tumor types are desperately needed.

Midkine (MDK) is a heparin-binding growth factor that is highly expressed in many malignant tumors, including lung cancers. We have previously reported that a MDK inhibitor: iMDK suppresses non-small cell lung cancer expressing MDK in vitro and in vivo without harming normal cells. Importantly, iMDK inhibits the PI3 kinase / Akt pathway and induces apoptosis in MDK expressing non-small cell lung cancer cells. In the present study, we have investigated the combination effect of iMDK and a mitogen-activated protein/extracellular signal-regulated kinase (MEK) inhibitor PD0325901. The combination treatment of iMDK and PD0325901 more effectively suppressed cell viability and colony formation, increased caspase-3 activity and induced apoptosis than those of single use in H441 and H2009 pulmonary adenocarcinoma cells harboring a G12 KRas mutation. Here, we describe the efficacy of the use of iMDK and PD0325901 for patients with inoperable advanced lung cancer including pulmonary adenocarcinoma harboring KRas mutations.

Citation Format: Takuya Fukazawa, Yutaka Maeda, Naomasa Ishida, Tomoki Yamatsuji, Munenori Takaoka, Minoru Haisa, Nagio Takigawa, Jeffery Whitsett, Yoshio Naomoto. Effective use of MDK/Midkine and MEK inhibitor to treat KRas mutated pulmonary adenocarcinoma cells. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 744. doi:10.1158/1538-7445.AM2014-744
Abstract 749: Highly potent and orally available SIK2 inhibitors block growth of human ovarian cancer cells in culture and xenografts
Authors: Alfredi Albandri , Zhang Shu , Mao Weiqu , Wang Yan , Takemori Hiroshi , Lu Zhen , Bast Robert C. , Vankayalapati Hariprasad
Published: May 2015

Salt Inducible Kinase 2 (SIK2) is a Ser/Thr kinase required for centrosome splitting and bipolar mitotic spindle formation. SIK2 is overexpressed in 30% of ovarian cancers associated with a poor prognosis. Knockdown of SIK2 with siRNA has inhibited ovarian cancer cell growth and enhanced paclitaxel sensitivity in cell culture and in xenografts. Given the challenges of delivering siRNA to cancer cells in vivo, we have sought small molecule inhibitors of SIK2 to permit clinical trials, alone and in combination with paclitaxel. Fragment-based design strategies utilizing SIK2 ATP-binding site residues, scaffold-hopping, SIK2 binding assay and subsequent SAR have led to the discovery of potent, selective, orally bioavailable first-in-class SIK2 inhibitors. Here we describe the identification and the preclinical characterization of ARN-3236 and its novel analogue ARN-3252 belonging to the same chemical class, suitable for oral administration. ARN-3236 and ARN-3252 compounds are highly potent (IC50: 1 and 5 nM), ATP competitive SIK2 inhibitors, characterized by high selectivity when tested against a panel of more than 456 kinases. ARN-3236 and ARN-3252 potently blocked proliferation of human ovarian cancer cell lines with endogenous SIK2 activation including OVCAR-3, SKOv3, HEY and ES-2 with an IC50 between 0.5 to 3.0 nM. Inhibition of proliferation has been observed in 9 additional ovarian cancer cell lines. The ARN-3236 and ARN-3252 exhibit a promising in vitro ADME profile and favorable in vivo PK parameters in mice and rats, including oral bioavailability. When tested in vivo in three murine subcutaneous xenograft models employing OVCAR-3, SKOv3 and ES-2 cells, ARN-3236 displayed dose-dependent tumor growth inhibition following daily oral administration at 30, 60 and 100 mg/Kg, with tumor regression observed at these dose levels. The lead identification, optimization, SAR, PK, single agent efficacy, efficacy in combination with paclitaxel and dose-dependent target modulation and the maintenance of SIK2 phosphorylation inhibition data will be presented. Given these specific small molecule inhibitors, SIK2 may provide a valuable target for treatment of a subset of human ovarian cancers.

Citation Format: Albandri Alfredi, Shu Zhang, Weiqu Mao, Yan Wang, Hiroshi Takemori, Zhen Lu, Robert C. Bast, Hariprasad Vankayalapati. Highly potent and orally available SIK2 inhibitors block growth of human ovarian cancer cells in culture and xenografts. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 749. doi:10.1158/1538-7445.AM2014-749
Abstract 75: PKR cooperates with an MDS driver mutation to worsen cytopenias and promote acute leukemia
Authors: Byrne Michael T. , Bennett Richard L. , Cheng Xiaodong , May W. Stratford
Published: May 2015

The interferon-inducible, dsRNA-dependent protein kinase, PKR, is activated by cellular stresses to inhibit protein synthesis and initiate apoptosis. Recently, we reported that expressing human PKR (TgPKR) in mouse hematopoietic tissues induced peripheral blood cytopenias and dysplastic changes in the bone marrow. Additionally, these findings were associated with reduced numbers of hematopoietic stem/progenitor cells (HSPCs) consistent with a myelodysplastic syndrome (MDS)-like phenotype. We have now tested whether TgPKR expression in HSPCs may cooperate with the Nup98-HoxD13 (NHD13) driver transgene. This NHD13 transgene induces a highly penetrant form of MDS with progression to acute leukemia in mice. TgPKR or PKR knockout (PKRKO) mice were crossed with the NHD13 transgenic mouse to generate TgPKR-NHD13 and PKRKO-NHD13 mice that were aged. The development of pancytopenia/MDS and evolution to acute leukemia were compared to NHD13 mice or to normal WT control mice.

Beginning at 5 months and persisting through 8 months of age, the TgPKR-NHD13 mice developed reduced WBC and platelet counts compared to NHD13 controls (WBC mean 2.6 vs. 3.5 x103 cells/µl, [p: < 0.01], and mean platelet counts of 576.9 vs. 814.3 x103 platelets/µl). Both cell types were significantly lower than WT controls. By contrast, PKRKO-NHD13 mice maintained higher WBC counts beginning at age 6 months (n=4) compared to NHD13 controls (n=13) (mean 7 vs. 2.5 x103 cells/µl, [6 mos.], 11.6 vs. 3.7 x103 cells/µl [7 mos.], 9.62 vs. 3.5 x103 cells/µl [8 mos.], p: <0.05).

To date, 1 of 13 of the NHD13 mice, aged 7-10 months, has developed acute leukemia. Of the TgPKR-NHD13 mice, 7 of 18 have died due to either acute leukemia (4/7), MDS with anemia requiring euthanasia (1/7), or due to unknown causes (2/7). By contrast, none of the PKRKO-NHD13 (n = 19) or WT mice (n= 11), both aged up to 9 months, have developed symptomatic MDS requiring euthanasia or acute leukemia

These data indicate that PKR may cooperate with the NHD13 driver oncogenic mutation to create a more aggressive MDS-like phenotype characterized by deeper peripheral blood cytopenias and an increased rate of evolution to AML. Alternatively, inhibition of PKR expression/activation may delay or forestall evolution of MDS/AML in the NHD13 background.

These findings suggest that PKR may be a potential novel therapeutic target in the treatment of MDS and its evolution to acute leukemia.

Citation Format: Michael T. Byrne, Richard L. Bennett, Xiaodong Cheng, W. Stratford May. PKR cooperates with an MDS driver mutation to worsen cytopenias and promote acute leukemia. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 75. doi:10.1158/1538-7445.AM2014-75
Abstract 751: Preclinical efficacy of the novel PIM inhibitor, JP_11646, in pancreatic cancer
Authors: Ding Yi , Lim Vun-Sin , Baldino Carmen M. , Caserta Justin , Flanders Yvonne , Dumas Stephane , Fetterly Gerald , Adjei Alex A.
Published: May 2015

Pancreatic ductal adenocarcinoma (PDAC) is often first diagnosed at an advanced stage with a poor prognosis. Current systemic treatment approaches have limited efficacy, pointing to an urgent need to develop novel therapies. Recent studies have shown that inhibition of Pim-2 activity via JP_11646, a novel pan-PIM inhibitor, resulted in decreased anchorage-independent growth of PDAC. The aim of this work is to examine the ability of JP_11646 alone and in combination with gemcitabine to inhibit the growth of pancreatic cancer cells in vitro and in vivo.

Cell viability was assessed using the MTS assay in two pancreatic cancer cell lines, MiaPaCa2 and PANC1. Cells were seeded at an average of 5x103 per well on 96-well plates and exposed to JP_11646 in a range of concentrations (0.01 - 5 µM) for 72 hours. Exposure to JP_11646 inhibited PANC1 and MiaPaCa2 cell growth in a dose-dependent manner, with IC50 values of 0.15 µM and 0.054 µM, respectively.

For in vivo experiments, SCID mice were implanted subcutaneously with 3x 106 MiaPaCa2 cells. Upon successful establishment of tumors (approximately 100 mm3), animals were randomly divided into groups for drug and control treatments. JP_11646 was given at 5 or 10 mg/kg by intraperitoneal injection (i.p. injection) once a day for 5 consecutive days from Monday to Friday for a total of six weeks. Gemcitabine i.p. was given at 45 mg/kg in combination treatment or 90 mg/kg as a single agent twice a week every Monday and Friday for a total of six weeks. In a dose-dependent manner, JP_11646 at 5 and 10 mg/kg significantly suppressed the growth of the pancreatic xenograft by 36% and 77% respectively, compare with control PBS treatment in SCID mice. Moreover, the combination of JP-11646 5 mg/kg and gemcitabine 45 mg/kg resulted in a greater tumor inhibition (83%) than either single agent alone [JP_11646 5 mg/kg (36%) or gemcitabine 90 mg/kg (69%)].

Taken together, our results suggest that JP_11646 is a potent inhibitor of pancreatic cancer growth with equivalent efficacy to the maximum tolerated dose of gemcitabine, and is synergistic in combination with gemcitabine.

Citation Format: Yi Ding, Vun-Sin Lim, Carmen M. Baldino, Justin Caserta, Yvonne Flanders, Stephane Dumas, Gerald Fetterly, Alex A. Adjei. Preclinical efficacy of the novel PIM inhibitor, JP_11646, in pancreatic cancer. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 751. doi:10.1158/1538-7445.AM2014-751
Abstract 756: First MNK degrading agents block phosphorylation of eIF4E, induce apoptosis, and inhibit cell growth, migration and invasion in triple-negative and HER2-overexpressing breast cancer cell lines
Authors: Ramalingam Senthilmurugan , Gediya Lalji , Purushottamachar Puranik , Kwegyir-Afful Andrew , Ramamurthy Vidya priyadarsini , Mbatia Hannah , Njar Vincent
Published: May 2015

Introduction: Retinoic acid metabolism blocking agents are known to exhibit a range of anticarcinogenic properties. This study investigated the anticancer efficacy of novel, potent retinamide retinoic acid metabolism blocking agents (RRs) in triple negative and Her 2 overexpressing breast cancer cells. Recent findings suggest that overexpression of eukaryotic translation initiation factor 4E (eIF4E) in breast cancers critically augments CAP-dependent mRNA translation and synthesis of proteins involved in cell growth, cell proliferation, invasion and apoptosis evasion. The oncogenic potential of eIF4E is strictly dependent on serine 209 phosphorylation by upstream MAPK-interacting kinases (Mnk). Targeting Mnk/eIF4E pathway for blocking Mnk function and eIF4E phosphorylation is therefore a novel approach for treating breast cancers particularly for HER-2-positive and triple negative breast cancers that have no indications for endocrine therapy or effective treatment regimes.

Methods: Triple negative and Her 2 overexprssing breast cancer cells were treated with retinamide RAMBAs and Mnk inhibitors and evaluated the effects of RRs on growth inhibition, MAPK/Mnk mediated eIF4E protein translational machinery and downstream biological effects in triple negative and Her 2 overexpressing breast cancer cells

Results: We report that the degradation of Mnk by RRs in breast cancer cells blocks eIF4E phosphorylation and subsequently inhibits cell growth, invasion and metastasis in addition to inducing apoptosis. Most importantly the anticancer efficacy of RRs was mediated via degrading Mnk rather than inhibiting its kinase activity like Mnk inhibitors (Cercosporamide and CGP 57380). RRs effect on p-eIF4E downregulation and growth inhibition were also far more potent than the clinically relevant retinoids and Mnk inhibitors, cercosporamide and CGP 57380.

Conclusion: Together our findings provide the first preclinical proof-of-concept of novel Mnk degrading agents for Mnk based therapeutic treatment of breast cancers.

Citation Format: Senthilmurugan Ramalingam, Lalji Gediya, Puranik Purushottamachar, Andrew Kwegyir-Afful, Vidya priyadarsini Ramamurthy, Hannah Mbatia, Vincent Njar. First MNK degrading agents block phosphorylation of eIF4E, induce apoptosis, and inhibit cell growth, migration and invasion in triple-negative and HER2-overexpressing breast cancer cell lines. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 756. doi:10.1158/1538-7445.AM2014-756
Abstract 759: ATP-binding cassette (ABC) genes genotype and expression: A potential association with pancreatic cancer development and chemoresistance
Authors: Pang Li , Word Beverly , Xu Joshua , Hammons George , Huang Shiew-Mei , Lyn-Cook Beverly
Published: May 2015

Genetic polymorphisms in ATP-Binding Cassette (ABC) transporter genes are associated with different responses to chemotherapy in various cancers including pancreatic cancer. In this study, four single nucleotide polymorphisms (SNPs) in the ABCB1, ABCC1 and ABCG2 genes were investigated in normal and pancreatic cancer specimens. The potential association with expression of the efflux pumps was also analyzed. The TT genotypes of G2677T and C3435T in ABCB1 gene were associated with lower risk of developing pancreatic cancer in the investigated populations (p=0.013, OR=0.35 and p=0.015, OR=0.29, respectively). To our knowledge, this is the first report of the common polymorphisms in ABCB1 gene affecting the genetic risk of developing pancreatic cancer. Moreover, compared to ABCB1 G2677T and C3435T wild-type homozygotes and heterozygotes, the expression of ABCB1 in mutant-type homozygotes (2677TT and 3435TT) was lower in normal pancreatic tissue (64.3% and 68.9%, respectively, p<0.05), and the same trend was also found in pancreatic cancer specimens. Interestingly, the pancreatic cancer cells MIA1, BXPC3 and CFPAC1 are ABCB1 2677TT-3435TT homozygotes. Cell viability assay revealed that these three cell lines were much more sensitive to gemcitabine than PANC1, SU86.86, PL-45, and ASPC1, which are either ABCB1 G2677T-C3435T wild type homozygotes or heterozygotes. These results are consistent with the clinical observation that for patients receiving post-operative gemcitabine chemotherapy, the overall survival is tended to be longer in the ABCB1 2677TT and 3435TT carriers. Conclusion: Polymorphisms in ABCB1 G2677T and G3435T were associated with different susceptibility to pancreatic cancer and may predict responses to chemotherapy.

Citation Format: Li Pang, Beverly Word, Joshua Xu, George Hammons, Shiew-Mei Huang, Beverly Lyn-Cook. ATP-binding cassette (ABC) genes genotype and expression: A potential association with pancreatic cancer development and chemoresistance. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 759. doi:10.1158/1538-7445.AM2014-759