bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 2613: Wnt/β-catenin signaling mediates the anti-tumor activity of three ginsenoside derivatives in lung cancer
Authors: Bi Xiuli
Published: May 2015

In previous publication, the anti-tumor activity of 25-hydroxyprotopanaxadiol (25-OH-PPD), a natural compound isolated from fruits of Panax ginseng, has been studied. In the current study, we investigated the anti-tumor activity of three derivatives synthesized from 25-OH-PPD, namely xl, 1c, and 8b, respectively. All three compounds significantly inhibited the growth of human lung cancer cells in vitro, while having lesser effect on the growth of normal primary muscle cells. In vivo, oral administration of three compounds could significantly inhibit the growth of xenograft tumors without affecting body weight. Further mechanistic study demonstrated that these compounds could decrease the expression levels of β-catenin and its downstream targets Cyclin D1, CDK4, and c-myc in A549 cells. Taken together, the results suggested that the anti-tumor activity exerted by these 25-OH-PPD derivatives is partially through β-catenin mediated signaling pathway in lung cancer cells, a finding that could potentially translate into a chemotherapeutic strategy for the treatment of lung cancer.

Note: This abstract was not presented at the meeting.

Citation Format: Xiuli Bi. Wnt/β-catenin signaling mediates the anti-tumor activity of three ginsenoside derivatives in lung 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 2613. doi:10.1158/1538-7445.AM2014-2613
Abstract 2634: Direct reprogramming of tumor cells: a basis for novel therapeutic approaches
Authors: Bluemel Lena , Huelsewig Carolin , Zaehres Holm , Schoeler Hans , Kiesel Ludwig , Bernemann Christof
Published: May 2015

Introduction

Direct reprogramming describes a process by which differentiated cells can be converted into virtually any other cell type, including terminal differentiated cells. This breakthrough offers a chance for regenerative medicine in order to treat patients suffering from degenerative diseases like Parkinson disease or tissue damages.

We believe that direct reprogramming of tumor cells provides a basis for novel targeted therapies of aggressive tumors. These tumors could be reprogrammed into tumors of another, less aggressive subtype, that could potentially be treated more easily than the parental tumor does.

We used the most aggressive breast cancer subtype - triple negative breast cancer - as research model. Its missing expression of both hormone receptors (HR) as well as HER2 renders this subtype more aggressive compared to HR or HER2 positive tumors. It also implies its poorer prognosis compared to other breast cancer subtypes, for which targeted therapies are available, e.g. anti-HER2 therapies that drastically improved formerly poor prognosis of HER2 positive cancer to a much better prognostic subtype nowadays.

We suggest that by use of direct reprogramming of triple negative breast cancer cells into HER2 positive cancer cells, these cells are susceptible to anti-HER2 targeted therapies, shifting its poor prognosis into better prognosis.

Methods

Triple negative breast cancer cell lines were transduced using HER2 expressing lentiviral particles. Molecular biological analyses were performed to investigate the functionality of the transgene. Subsequently, targeted therapies against HER2 followed by molecular analyses of effects were performed.

Results

The expression of HER2 could be shown by both mRNA (using qPCR) as well as protein (Western Blot) approaches. Additionally, immunofluorescence analysis confirmed membrane localization of HER2.

Furthermore, preliminary results using targeted anti-HER2 therapies showed reduction of proliferative capacity of formerly triple negative breast cancer cells.

Conclusion

We conclude that direct reprogramming might become a tool of converting aggressive tumor types into cells susceptible to targeted therapies. Its current system describes a proof-of-principal whether reprogramming approaches might find a way into clinical settings someday. Nevertheless, strong hurdles have to be taken to make such approaches valuable for (breast) cancer patients.

Citation Format: Lena Bluemel, Carolin Huelsewig, Holm Zaehres, Hans Schoeler, Ludwig Kiesel, Christof Bernemann. Direct reprogramming of tumor cells: a basis for novel therapeutic approaches. [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 2634. doi:10.1158/1538-7445.AM2014-2634
Abstract 2639: Development of immunocytotoxic RNA therapeutics for human melanoma
Authors: Lee Jaewoo , Lee Youngju , Sullenger Bruce A.
Published: May 2015

Pattern recognition receptors (PRRs) are a pivotal component of anti-infectious immunity, and selective induction of PRR-mediated apoptosis in cancer cells represents a novel therapeutic strategy. Retinoic acid inducible gene-I (RIG-I) is a cytoplasmic PRR that recognizes virus-associated molecular patterns, such as uncapped 5′triphosphate (5′ppp) RNA. RIG-I activation triggers innate immune response and apoptosis in infected cells, resulting in the inhibition of viral spread. Interestingly, certain cancer cells are highly sensitive to RIG-I-mediated apoptosis, and treatment with RIG-I-stimulating RNAs can selectively kill cancer cells and facilitate the induction of anti-cancer immunity. Therefore, RIG-I-stimulating RNAs may prove valuable as immunostimulatory and anti-cancer agents. Because RNAs are extremely sensitive to serum nucleases, modified RNAs have been employed to increase the stability of RNA-based therapeutics. Such modifications, however, often abrogate the immunostimulatory activity of RNAs, which hinders their development as immunostimulatory agents. Herein, we demonstrate that short single-stranded RNAs (ssRNAs) (23-93 nucleotides) with 5′ppp and stem-loop structure(s) are a potent stimulus for type I interferon (IFN) production and apoptosis of human melanoma and prostate cancer cells. 2′fluoro (2′F) modification of these 5′ppp ssRNAs not only improves serum stability, but also enhances the ability of the RNAs to induce IFNβ production and apoptosis of human cancer cells, compared to their unmodified counterparts, while 2′ O-methyl modification abrogates the anti-cancer and IFN-inducing activities of 5′ppp ssRNAs. These 5′ppp 2′F ssRNAs elicit RIG-I- and mitochondrial antiviral-signaling protein-mediated IFN production and cytotoxic effects. This study suggests that such modified RNAs may represent a novel and effective anti-cancer therapeutic.

Citation Format: Jaewoo Lee, Youngju Lee, Bruce A. Sullenger. Development of immunocytotoxic RNA therapeutics for human melanoma. [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 2639. doi:10.1158/1538-7445.AM2014-2639
Abstract 2658: GPEx® system to increase production of pritumumab in a CHO cell line
Authors: Bleck Gregory T. , Gupta Rishab K. , Kotlan Beatrix , York Dona , Glassy Mark C.
Published: May 2015

Pritumumab, a natural human IgG1 kappa antibody isolated from a lymph node of a patient with cervical carcinoma, has been used in a Phase II setting with brain cancer patients. The original human-human hybridoma secreted approximately 1 picogram of antibody per cell per day. This level of the antibody production posed cost constrains for late stage therapeutic clinical trials. To generate a more commercially viable antibody, a pritumumab-secreting Chinese hamster ovary (CHO) cell line was created using the GPEx® technology. This technology involved construction and cloning of heavy and light chain DNA. Both DNA sequences were cloned into the expression vector and transduced into HEK 293 cells that constitutively produces the MLV gag, pro, and pol. The pritumumab cell line was made by performing multiple rounds of transduction (multiplicity of > 1000 retrovector particles/cell) of the GPEx® Chinese Hamster Ovary (GCHO) parental cell line with retrovector made from the gene construct developed to express the pritumumab antibody light chain (LC) and the pritumumab antibody heavy chain (HC). Five independent transductions were performed: two LC and three HC. Limiting dilution method was used to establish clonal cell lines. Top clones were selected based on pritumumab antibody titer. Pritumumab expression was determined by Protein A HPLC using a generic IgG standard. Clearly, single copies of genes were inserted efficiently in unique locations throughout the genome of the CHO cells to obtain genetically stable cell line that expressed high levels of the antibody, and represented more than a 40-fold increase in production of the antibody over the original hybridoma. Flow cytometry binding and immunohistological analyses demonstrated comparability between the recombinant form of pritumumab and the hybridoma form of the protein. Thus, high level of specific productivities and titers of the CHO clones developed through the GPEx® system will allow the therapeutic antibody program to move forward into large and extended clinical trials.

Citation Format: Gregory T. Bleck, Rishab K. Gupta, Beatrix Kotlan, Dona York, Mark C. Glassy. GPEx® system to increase production of pritumumab in a CHO cell line. [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 2658. doi:10.1158/1538-7445.AM2014-2658
Abstract 2674: Stroma biology identifies heparins as differentiating agents in neuroblastoma
Authors: Knelson Erik H. , Gaviglio Angela L. , Nee Jasmine C. , Starr Mark D. , Nixon Andrew B. , Marcus Stephen G. , Blobe Gerard C.
Published: May 2015

The neuroblastoma tumor stroma is thought to suppress neuroblast growth via release of soluble differentiating factors. Here we identify these factors and design a novel therapy based on their mechanism of action. We show that expression of heparan-sulfate proteoglycan co-receptors (HSPGs), including TβRIII, GPC1, GPC3, SDC3, and SDC4, is decreased in neuroblasts, localized to the stroma and correlates with improved prognosis. Treatment with soluble HSPGs promoted neuroblast differentiation via FGFR1, Erk, and Id1. HSPGs also enhanced differentiation from FGF2 released by the stroma. The anticoagulant heparin had similar differentiating effects, leading to decreased neuroblast proliferation. Dissection of individual sulfation sites identified 2-O, 3-O-de-sulfated heparin (ODSH) as a differentiating agent that suppressed orthotopic xenograft growth while avoiding anticoagulation. These studies uncover the critical components of the differentiating stroma secretome in neuroblastoma and the central mechanism by which they act. We translate these biologic insights into novel prognostic and therapeutic biomarkers, as well as therapeutic differentiation strategies for clinical development. More generally, our work demonstrates that tumor stroma biology can inform design of targeted molecular therapeutics.

Citation Format: Erik H. Knelson, Angela L. Gaviglio, Jasmine C. Nee, Mark D. Starr, Andrew B. Nixon, Stephen G. Marcus, Gerard C. Blobe. Stroma biology identifies heparins as differentiating agents in neuroblastoma. [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 2674. doi:10.1158/1538-7445.AM2014-2674
Abstract 2680: Inhibition of activin-like kinases 4 and 5 attenuates cancer cachexia associated muscle wasting
Authors: Levolger Stef , Bruin Ron W.F. de , IJzermans Jan N.M.
Published: May 2015

Background: Cancer cachexia has a detrimental effect on patient survival. Cachectic patients experience reduced quality of life and have a decreased survival time. The underlying mechanism behind cancer cachexia is not yet fully understood. Recent experimental data suggests myostatin signaling may be a key contributor in the pathogenesis of cancer cachexia. Activin receptor IIB / activin-like kinase 4/5 heterodimer activation by myostatin leads to catabolic muscle degradation. SB-431542 is a potent inhibitor of activin-like kinases 4 and 5. We aimed to assess its potential in the treatment of cancer cachexia in an experimental rodent model.

Methods: All experiments were approved by the local Animal Ethics Committee. 24 CD2F1 were inoculated subcutaneously with 0.5 x 106 colon-26 murine adenocarcinoma cells to induce cachexia. The mice were allocated randomly into one of four experimental groups: healthy control, tumor-bearing control, tumor-bearing vehicle treated and tumor-bearing SB-431542 treated. All mice were weighed daily. Tumor size was assessed every other day, starting day 9 post inoculation. Four-paw grip strength was determined weekly using a grip-strength meter. SB-431542 was reconstituted in DMSO 1 mg/mL. From day 5 post inoculation, allocated mice received 10 mg/kg SB-431542, or vehicle intraperitoneally until sacrifice on day 20.

Results: All tumor-bearing mice had a reduction in body weight compared to controls, 21.1 ± 2.1 g versus 30.0 ± 1.3 g respectively (p < 0.0001). No differences in body weight were found between the tumor-bearing groups. Despite weight loss, SB-431542 treated animals had no reduction in grip strength. Grip strength directly after tumor inoculation was 200.9 ± 11.3 g, and on day 14 211.3 ± 20.4 g. Vehicle treated animals showed a reduction from 204.0 ± 19.1 g to 174.8 ± 13.7 g (p = 0.0158). Mean wet muscle weight of the m. tibialis anterior was significantly preserved in SB-431542 treated animals versus tumor-bearing vehicle treated animals (53.8 mg vs. 40.5 mg, p = 0.0171) as well as tumor-bearing untreated animals (53.8 mg vs. 34.7 mg, p = 0.0002).

Conclusion: These findings suggest that inhibition of activin-like kinases 4 and 5 by SB-431542 attenuates cancer cachexia associated muscle loss and loss of muscle force in experimental cancer cachexia, and further emphasizes the role of myostatin/activin signaling.

Citation Format: Stef Levolger, Ron W.F. de Bruin, Jan N.M. IJzermans. Inhibition of activin-like kinases 4 and 5 attenuates cancer cachexia associated muscle wasting. [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 2680. doi:10.1158/1538-7445.AM2014-2680
Abstract 2682: ELTD1 as a target for anti-cancer therapy in rodent gliomas
Authors: Towner Rheal A. , Pody Richard , Smith Nataliya , Saunders Debra , Njoku Charity , Wren Jonathan D.
Published: May 2015

Despite current therapies, glioblastoma multiforme (GBM) is a devastating cancer with a very poor prognosis. Specific protein biomarkers for GBM enable not only new prognostic avenues to tailor treatment, but valuable therapeutic targets to interfere with GBM growth. We recently discovered a new biomarker for high-grade gliomas, ELTD1 (epidermal growth factor, latrophilin, and 7 transmembrane domain-containing protein 1 on chromosome 1), via a novel bioinformatics approach, GAMMA (Global microarray meta-analysis). ELTD1 was found to be significantly higher (p<0.05) in high-grade gliomas (50 patients) compared with low-grade gliomas (21 patients). ELTD1 gene expression was found to be associated with tumor grade, survival across grade, and an increase in the mesenchymal subtype. From our previous results we hypothesized that ELTD1 may be a potential therapeutic target in high-grade gliomas. We tested the hypothesis in an orthotopic GL261 mouse glioma model in animals treated with an anrti-ELTD1 antibody, compared to those that were treated with an anti-VEGF antibody or an anti-c-Met antibody, and untreated tumors. Tumor volumes were measured by morphological magnetic resonance imaging (MRI). Our data in orthotopic GL261 glioma-bearing mice shows that injection of anti-ELTD1 antibodies lead to a significant decrease in tumor volumes (p<0.0001) and a significant increase in animal survival (p<0.05), superior to that achieved by a mouse anti-VEGF antibody or an antibody against c-Met, when compared to untreated mice. Tumor volumes were obtained at various time-points, and compared at 21 days following intracerebral implantation of GL261 cells in male C57BL6 mice. These tumor volumes at 21 days were 86.03+/-41.54 mm3 for untreated mice (n=5); 13.04+/-5.35 mm3 for anti-ELTD1 treated mice (n=5); 33.16+/-12.48 mm3 for anti-VEGF treated mice (n=4); and 28.49+/-11.11 mm3 for anti-c-Met treated mice (n=5). The mean days of survival for untreated, ELTD1, VEGF or c-Met treatment groups were 23.8+/-1.79, 28.2+/-2.39, 27+/-1.15 or 27+/-1.87 days, respectively. These pre-clinical results indicate that an additional therapy in the form of an anti-ELTD1 antibody either as a sole agent or in combination with current or new therapies could potentially provide high-grade glioma patients with a better prognostic outcome.

Citation Format: Rheal A. Towner, Richard Pody, Nataliya Smith, Debra Saunders, Charity Njoku, Jonathan D. Wren. ELTD1 as a target for anti-cancer therapy in rodent gliomas. [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 2682. doi:10.1158/1538-7445.AM2014-2682
Abstract 2687: CK2 inhibitor CX-4945 modulates AKT, NF-kB, TP53 and MEK inhibitor PD-325901 targets AP1 mediated CK2 inhibitor drug resistance in head and neck cancer
Authors: Bian Yansong , Han Jiawei , Kannabiran Vishnu , Mohan Suresh , Friedman Jay , Anderes Kenna , Chen Zhong , Waes Carter Van
Published: May 2015

We previously identified upregulated kinase CK2 as an activator of NF-B and repressor of TP53 in promoting the malignant phenotype of head and neck squamous cell carcinoma (HNSCC). Here, we investigate the anti-tumor effects of a small molecule CK2 inhibitor CX-4945, alone and in combination with MEK inhibitor PD-0325901 (PD-901), in human HNSCC models in vitro and in vivo. CX-4945 IC50s ranged from 3.4 µM to 11.9 µM in 9 UMSCC cell lines. CX-4945 caused S and G2/M cell cycle arrest, and induced sub-G0 DNA fragments, indicating cell death. CX-4945 inhibited NF-B and BcL-XL prosurvival reporter genes in wild type (wt) TP53 (UMSCC1) and mutant (mt) TP53 (UMSCC46) cell lines, and concurrently upregulated proapoptotic TP53, p21 and prosurvival AP-1 activity only in the wtTP53 cell line. Correspondingly, CK2 phosphorylation of AKT S129 as well as T308 and S473 prosurvival signaling was reduced in both cell lines, but AP-1 inducing p-Erk1/2Thr202/204 was increased in the wtTP53 cell line. In the UMSCC1 xenografts, CX-4945 treatment significantly decreased PI3K/Akt/mTOR pathway signaling by immunostaining. While CX-4945 increased TP53 and TUNEL apoptosis marker staining at early time points (13 days after CX4945 treatment), an opposing increase in p-Erk, FosL1, cJun, JunB, and proliferation (Ki67) were also observed. Consistent with these opposing effects, no significant tumor reduction or improvement in survival was observed by CX-4945 alone. However, combination of CX-4945 with MEK/ERK inhibitor PD-901 exhibited significant synergistic anti-proliferative effects in vitro. Significant anti-tumor effects were observed with MEK inhibitor alone and in combination with CX-4945 in vivo, further supporting a role for MEK/ERK/AP-1 in resistance to CX-4945 in this HNSCC model.

Supported by NIH Medical Research Scholars Program and NIDCD intramural projects ZIA-DC-000016, 73 and 74.

Citation Format: Yansong Bian, Jiawei Han, Vishnu Kannabiran, Suresh Mohan, Jay Friedman, Kenna Anderes, Zhong Chen, Carter Van Waes. CK2 inhibitor CX-4945 modulates AKT, NF-kB, TP53 and MEK inhibitor PD-325901 targets AP1 mediated CK2 inhibitor drug resistance in head and neck 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 2687. doi:10.1158/1538-7445.AM2014-2687
Abstract 2698: Degrasyn-like symmetrical compounds: Possible therapeutic agents for multiple myeloma (MM-I)
Authors: Bornmann William G. , Peng Zhenghong , Maxwell David , Sun Duoli , Bhanu Basvoju A. , Talpaz Moshe , Donato Nicholas , Levitzki Alexander
Published: May 2015

A series of degrasyn-like symmetrical compounds have been designed, synthesized, and screened against B cell malignancy (multiple myeloma, mantle cell lymphoma) cell lines. The lead compounds T5165804 and CP2005 showed higher nanomolar potency against these tumor cells in comparison to degrasyn and inhibited Usp9x activity in vitro and in intact cells. These observations suggest that this new class of compounds holds promise as cancer therapeutic agents.

Citation Format: William G. Bornmann, Zhenghong Peng, David Maxwell, Duoli Sun, Basvoju A. Bhanu, Moshe Talpaz, Nicholas Donato, Alexander Levitzki. Degrasyn-like symmetrical compounds: Possible therapeutic agents for multiple myeloma (MM-I). [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 2698. doi:10.1158/1538-7445.AM2014-2698
Abstract 2717: DMH1, a small molecule inhibitor of BMP type I receptors, suppresses growth and invasion of lung cancer
Authors: Huang Ying , Lee Rachel , Chang Andy , Fan Jeffery , Labib Chantelle , Parsa Cyrus , Orlando Robert , Andresen Bradley , Hao Jijun
Published: May 2015

Bone morphogenetic proteins (BMPs) are members of the TGF-β superfamily and their biological activity is mediated by the formation of heterodimeric complexes of BMP type I and type II receptors of serine/threonine kinases. BMPs play an important role in regulating cell proliferation, differentiation and migration, processes that are involved in carcinogenesis of many types of cancer. BMP-2 has been shown overexpressed in human non-small cell lung cancer (NSCLC) and enhances lung tumorigenesis, suggesting that blocking the BMP signaling may be an effective therapeutic approach for NSCLC. Although previous work demonstrated that known protein-based BMP antagonists such as Noggin may reduce lung tumor growth, their clinical application could be limited by short half-lives and poor intra-tumor delivery. In a previous zebrafish embryo-based structure and activity study, we identified DMH1, a highly selective small molecule inhibitor which specifically antagonize the intracellular kinase domains of BMP type I receptors, the critical mediators of BMP signaling. In the present study, we found that DMH1 potently reduced lung cell proliferation, promoted cell death, and decreased cell migration and invasion in vitro by blocking the BMP signaling, as indicated by the reduction of Smad 1/5/8 phosphorylation and gene expression of Id1, Id2 and Id3 in A549 and H460 cells. In an in vivo study, treatment by intraperitoneal injection of DMH1 (5 mg/kg) for four weeks significantly reduced the growth of A549-derived xenograft in SCID mice. In conclusion, our study indicates that small molecule inhibitors of BMP type I receptors may offer a promising novel therapeutic strategy for lung cancer.

Citation Format: Ying Huang, Rachel Lee, Andy Chang, Jeffery Fan, Chantelle Labib, Cyrus Parsa, Robert Orlando, Bradley Andresen, Jijun Hao. DMH1, a small molecule inhibitor of BMP type I receptors, suppresses growth and invasion of lung 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 2717. doi:10.1158/1538-7445.AM2014-2717
Abstract 2720: In vitro evaluation of a novel chemotherapeutic agent, NecroX-7, in human Burkitt lymphoma cells
Authors: Kim Eun- Jung , Lee Eun Sol , Im Keon- Il , Kim Soon H. , Lim Jung- Yeon , Kim Nayoun , Cho Seok- Goo
Published: May 2015

NecroX-7 is a novel small molecule of the NecroX series, its chemical compound is C25H32N4O4S2 with molecular weight 516.67 based on the indole-moiety. It prevents from oxidative stress-induced cell death. NecroX-7 prevented the release of HMGB1 or ameliorated hepatic IR injury. It is shown that NecroX-7 can inhibit NAPDH oxidase activity and osteoclast differentiation. Furthermore, NecroX-7 protected against APAP-induced hepatic injury by directly binding to NAPQI. However, the function and the underlying mechanisms of NecroX-7 in cancer cell growth have not been well established. This study was aimed at evaluating the efficacy as anticancer agent in human lymphoma cells.

Human Burkitt lymphoma cell lines were treated NecroX-7 in vitro. The effects of NecroX-7 treatment were evaluated using MTS assay for cell viability and annexin-V/propidium iodide labeling for apoptosis. Cell cycle was analyzed by Flow cytometry. Western blotting was used to look for NecroX-7 induced protein changes.

As results, NecroX-7 treatment efficiently inhibited cell growth at dose- and time- dependent and induced apoptosis in cell lines. Apoptosis was showed by accumulation of annexin-V and PI-positive cells, caspase-3 activation and induction of PARP cleavage. The IC50 values of NecoX-7 in cell lines were around 50 uM. NecroX-7 induced G2/M phase cell cycle arrest in Ramos and Daudi cells.These results suggest that NecroX-7 is a potential anticancer agent for treatment of human Burkitt lymphoma cells and provide a rational for preclinical and clinical evaluation of NecoX-7 for lymphoma therapy.

Citation Format: Eun- Jung Kim, Eun Sol Lee, Keon- Il Im, Soon Ha Kim, Jung- Yeon Lim, Nayoun Kim, Seok- Goo Cho. In vitro evaluation of a novel chemotherapeutic agent, NecroX-7, in human Burkitt lymphoma 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 2720. doi:10.1158/1538-7445.AM2014-2720
Abstract 2722: Suppression of breast cancer cell migration by novel inhibitors that target transient receptor potential-melastatin-like 7 (Trpm7) kinase activity
Authors: Kaoud Tamer Saad , Park Jihyun , Tavares Clint D.J. , Mitra Shreya , Cano Micael , Tseng Chun-Chia , Dalby Kevin N.
Published: May 2015

TRPM7 (transient receptor potential melastatin 7) encodes a calcium permeable non-selective cation channel implicated in cell adhesion and magnesium homoeostasis. The TRPM7 gene encodes for a protein kinase whose activity is linked to the control of actomyosin contractility. TRPM7 mediates adhesion and migration of MDA-MB-231 breast cancer cells and recently has been reported to promote breast tumor cell metastasis. The lack of cell-permeable pharmacological inhibitors of the kinase domain represents a barrier to fully understanding kinase function. Herein, we describe the discovery of several compounds that target TRPM7 kinase activity and which were shown to decrease the binding of Myosin IIB to TRPM7 in HEK293 cells and MDA-MB-231 breast cancer cells transfected with pCMV6-TRPM7. Interestingly, two of the inhibitors potentially inhibited MDA-MB-231 breast cancer cells migration that have been reported to be regulated by TRPM7 kinase activity. Finally, magnesium starvation, which promotes TRPM7 kinase activity, induces phosphorylation of eEF2. Treatment of cells with several of the compounds decreased eEF2 phosphorylation under conditions of magnesium starvation, consistent with the notion that they inhibit TRPM7 kinase activity in cells.

Citation Format: Tamer Saad Kaoud, Jihyun Park, Clint D.J. Tavares, Shreya Mitra, Micael Cano, Chun-Chia Tseng, Kevin N. Dalby. Suppression of breast cancer cell migration by novel inhibitors that target transient receptor potential-melastatin-like 7 (Trpm7) kinase activity. [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 2722. doi:10.1158/1538-7445.AM2014-2722
Abstract 2723: Breast cancer type 1 susceptibility protein mimetics induce specific estrogen receptor confirmations and inhibit MCF7 breast cancer cell proliferation
Authors: Asare Bethany Kristen , Katche Christ Ange , Rajnarayanan Rajendram V.
Published: May 2015

The human Estrogen Receptor (hER) is present in 70% of breast cancers, and dysregulation of hER signaling can lead to aberrant cell growth and proliferation. Known anti-estrogens used in treatments of breast cancer today, tamoxifen and raloxifene cause hER to undergo conformational changes and inhibit normal hER signaling by directly binding to the ligand binding pocket. However, often breast cancer cells become resistant to tamoxifen, and prolonged tamoxifen treatment can lead to endometrial cancers. Breast Cancer Type 1 Susceptibility protein (BRCA1) is a well characterized inhibitor of breast cancer cell growth. BRCA1 plays an important role in maintaining genomic stability through various DNA repair mechanisms. It is mutated in approximately 50% of breast cancer cases that are associated with heredity. While the majority of breast cancer cases are “sporadic” or unassociated with heredity, BRCA1 is expressed 30 to 40 % less in sporadic breast cancers. BRCA1 has also been shown to associate directly with hER, and inhibit transactivation of hER. This association and inhibition of hER transcriptional activity is reversed by cyclin D1. This, in conjunction with studies that have shown that cyclin D1 gene and protein levels are amplified and overexpressed respectively in breast cancers suggest that the normal regulation of hER by BRCA1 and cyclin D1 may be shifted in breast cancers to primarily regulation (activation) by cyclin D1 and other coactivators. A decrease in BRCA1 is associated with acquired tamoxifen resistance, suggesting that BRCA1 may play a critical role in maintaining breast cancer cells sensitivity to tamoxifen. The hER binding region of BRCA1 contains the known corepressor binding motif LXXIIXXXL (amino acids 78-95). Here we present a study of several small molecules identified based on pharmacophoric features of previously found conformation sensing BRCA1 peptides. BRCA1 mimetics induce unique ER conformations and inhibit breast cancer cell growth (MCF7). Further development of these compounds could lead to viable alternative breast cancer treatments as well as supplemental treatments in the anti-estrogen resistant cases.

Acknowledgements: This research was supported via funds from the New York State, National Institutes of Health (5P20MD002725), through the NCMHD -RIMI program (RVR) and NSF LSAMP Bridge to Doctorate grant (BKA).

Citation Format: Bethany Kristen Asare, Christ Ange Katche, Rajendram V. Rajnarayanan. Breast cancer type 1 susceptibility protein mimetics induce specific estrogen receptor confirmations and inhibit MCF7 breast cancer cell proliferation. [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 2723. doi:10.1158/1538-7445.AM2014-2723
Abstract 2732: Identification of a small molecule selectively kill mismatch repair deficient tumors
Authors: Myung Kyungjae
Published: May 2015

Lynch Syndrome, a genetic disorder caused by defects in the DNA mismatch repair (MMR) pathway, accounts for approximately 5% of all colon cancer cases. Lynch Syndrome tumors have proven to be resistant to most conventional chemotherapeutic agents, making surgery the best treatment option available. Here we screened NIH small molecule library for their ability to selectively kill cells with mutations in the MSH2 gene, and identified a small molecule that could target MMR-deficient cancer cells. This small molecule intercalates DNA, trigering a DNA damage response in MSH2-proficeint cells. In MSH2-deficient cells, continued replication in the presence of this small molecule leads to the formation of DNA double-strand breaks and ultimately results in apoptosis in the G2/M phase of the cell cycle. In addition, this small molecule is not mutagenic. Our results suggest that this small molecule may offer an improved treatment option for patients with tumors characterized mutations in the MMR pathway.

Citation Format: Kyungjae Myung. Identification of a small molecule selectively kill mismatch repair deficient tumors. [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 2732. doi:10.1158/1538-7445.AM2014-2732
Abstract 2767: Identification of kinase fusion genes in bladder cancer through kinome-centered RNA sequencing
Authors: Groenendijk Floris , Rink Iris de , Mertens Laura , Broeks Annegien , Neuzillet Yann , Jong Jeroen de , Rhijn Bas van , Bernards Rene , Heijden Michiel van der
Published: May 2015

Urothelial carcinoma (UC) of the bladder is one of the most common cancers worldwide. The treatment of patients with metastatic or locally advanced UC consists of platinum-based chemotherapy. Unfortunately, a large number of patients will ultimately develop resistance. Therapeutic options at that point are very limited: the last FDA drug approval for the treatment of bladder cancer dates back more than 2 decades. Identification of activated signaling pathways in UC can provide new targets for treatment. Recent DNA and RNA sequencing projects in invasive UC have revealed somatic mutations in several cancer genes. Some of these mutated genes, such as FGFR3 and PIK3CA, could potentially guide therapy. However, our knowledge of gene rearrangements in bladder cancer remains limited. These fusion genes often involve multiple fusion partners, as was reported for FGFR3 fusions in bladder cancer, which represents a significant challenge for discovery and for subsequent diagnostic screening. Therefore, a global detection method is needed to fully understand the diversity of alterations driving this disease. We used a high-throughput platform to systematically profile kinase fusions through specific enrichment of kinase transcripts. Using this approach, we screened 80 muscle invasive UC specimens and identified a number of activating mutations and novel fusion transcripts. The fusion genes identified in this discovery set will be validated in a second cohort of UC specimens to determine their frequency. Functional validation will be presented for some of these fusion genes. These genetic alterations may provide new avenues for individualized molecular treatment of UC patients.

Citation Format: Floris Groenendijk, Iris de Rink, Laura Mertens, Annegien Broeks, Yann Neuzillet, Jeroen de Jong, Bas van Rhijn, Rene Bernards, Michiel van der Heijden. Identification of kinase fusion genes in bladder cancer through kinome-centered RNA sequencing. [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 2767. doi:10.1158/1538-7445.AM2014-2767
Abstract 2769: PKC/MARCKS pathway is a novel therapeutic target associated with breast cancer malignancy potential and paclitaxel resistance
Authors: Chen Ching-Hsien , Arif Muhammad , Chang Wen-Hsin , Yuan Yuan , Zhai Jing , Ann David K. , Wu Reen
Published: May 2015

Increasing evidence had suggested important roles of protein kinase C (PKC)-mediated phosphorylation of myristoylated alanine-rich C kinase substrate (MARCKS) in modulating various cellular processes, including cancer cell growth and metastasis. However, there is a lack of information regarding to the roles of MARCKS and its pSer 159/163 phosphorylated product in breast cancer cells and tissues. To tackle this concern, we recently initiated both immunohistochemical and western blot analyses on a series of clinical specimens and several breast cancer cell lines. We have observed a significant elevation of phospho-MARCKS associated with advanced-stage breast cancer tissues as compared with benign ones, particularly in triple-negative breast cancer (TNBC) tissues and cell lines. Knockdown of MARCKS expression resulted in suppressions of lamellipodia/filopodia formation and migration/invasion as well as down-regulation of Src activity in these TNBC cell lines. Of note, MARCKS-silenced TNBC cells grew much more slowly and more sensitive to paclitaxel than the control and parental cells. Treatment with paclitaxel was shown to induce MARCKS phosphorylation in a dose-dependent manner, which may be related to an enhanced paclitaxel resistance in some of TNBC cells. However, PKC inhibitors were able to abrogate paclitaxel-induced MARCKS phosphorylation. Consistent with this potential, treatments of TNBC cells with a MARCKS N-terminus sequence peptide, namely MANS, to down regulate PKC/MARCKS pathway not only attenuated the associated aggressive phenotype but also synergistically enhanced paclitaxel-induced cytotoxicity in vitro and in vivo. These results demonstrate an association of PKC-mediated MARCKS phosphorylation with breast cancer malignancy potential and MARCKS phosphorylation as a predictor of paclitaxel resistance in TNBC cells. It is suggestive that an inhibition of PKC/MARCKS pathway may serve as an alternative therapeutic strategy for enhancing efficacy of chemotherapy.

Citation Format: Ching-Hsien Chen, Muhammad Arif, Wen-Hsin Chang, Yuan Yuan, Jing Zhai, David K. Ann, Reen Wu. PKC/MARCKS pathway is a novel therapeutic target associated with breast cancer malignancy potential and paclitaxel resistance. [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 2769. doi:10.1158/1538-7445.AM2014-2769
Abstract 2772: Ceramide analog sensitizes breast cancer cells to Fas-mediated apoptosis to suppress spontaneous lung metastasis
Authors: Li Xia , Paschall Amy V. , Bai Aiping , Bielawski Jacek , Bielawska Alicja , Liu Kebin
Published: May 2015

Fas is a member of the TNF death receptor superfamily. Despite other “non-apoptotic” cellular responses emanating from its signaling, the major and best known function of Fas is apoptosis. To avoid apoptosis, cancer cells, including breast cancer cells, tend to down-regulate Fas expression or alter the expression of key mediators of the Fas-mediated apoptosis signaling pathway to advance the disease. Therefore, therapeutic intervention of tumor cell resistance to Fas-mediated apoptosis potentially represents an effective approach to render tumor cell sensitivity to FasL+ cytotoxic T lymphocytes (CTL) of the host immunosurveillance system or to CTL-based adoptive cancer immunotherapy to suppress tumor progression. We report here that sublethal doses of ceramide analog LCL85 effectively overcome metastatic human breast cancer cells to FasL-induced apoptosis in vitro. Although it has been shown that ceramide targets the Bcl-2 family proteins to induce tumor cell apoptosis, we observed that LCL85 does not alter Bak, Bax, Bcl-2 and Bcl-xL protein levels in metastatic human breast cancer cells. Instead, we determined that LCL85 dramatically decreased cIAP1 and xIAP protein levels in the metastatic human breast cancer cells. Consistent with its apoptosis sensitization activity, subtoxic doses of LCL85 suppressed primary breast cancer growth. More importantly, subtoxic doses of LCL85 effectively suppressed spontaneous lung metastasis in an orthotopic breast cancer mouse model. Furthermore, LCL85 exhibited no significant liver toxicity in vivo at the effective doses. Our data thus suggest that LCL85, although effective as a single agent in suppression of tumor development at high doses, might be more valuable if used at a sublethal dose as a sensitizer for enhancing the efficacy of FasL-based cancer therapy, particularly CTL-based cancer immunotherapy.

Note: This abstract was not presented at the meeting.

Citation Format: Xia Li, Amy V. Paschall, Aiping Bai, Jacek Bielawski, Alicja Bielawska, Kebin Liu. Ceramide analog sensitizes breast cancer cells to Fas-mediated apoptosis to suppress spontaneous lung 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 2772. doi:10.1158/1538-7445.AM2014-2772
Abstract 2783: Variability of HER2 expression between in vitro and in vivo models within gastric cancer cell lines
Authors: Gim Youme , Park Hee Seo , Jung Hae Rim , Chang Hae Ryung , Nam Seungyoon , Choi Yong Doo , Ku Ja-Lok , Kim Yon Hui
Published: May 2015

In the process of developing individualized cancer therapeutics, tumor derived cell line based preclinical (in vitro and in vivo) methods have been widely used. Patient derived genome analysis revealed significant cancer biomarkers for targeted drug development. Classic cancer biomarker, HER2, overexpression was discovered as a cancer biomarker and as a druggable target in breast cancer, which lead to the development of Trastuzumab. HER2 is overexpressed in 10-25% of gastric cancer, and treatment with Trastuzumab showed positive yet limited activity in advanced gastric cancer treatment in the ToGA study. These results present HER2 as an attractive target for gastric cancer. However, Gillet and colleagues reported the challenges in the use of in vitro and in vivo studies for drug validation and development. They reported variance in gene expression patterns between the in vitro and in vivo context within a single cancer cell line. In our study using gastric cancer derived cell lines, we observed differences in HER2 expression between in vitro and in vivo xenograft model. Also, we show the potential promising in vivo xenograft model in the development of HER2 targeting agents for gastric cancer.

Eleven out of 25 gastric cancer cell lines showed HER2 expression, which was demonstrated using the IHC assay on a cell microarray. Sixteen out of 25 cell lines successfully produced xenograft models. Gastric cancer cell lines (SNU-5, SNU-16, SNU-638, SNU-1967, MKN-1, MKN-28, and NUGC-3) that had no HER2 expression when cultured in vitro showed HER2 expression in vivo. Two cell lines (NCC-19 and NCI-N87) that had HER2 expression in vitro showed a decrease in HER2 expression in vivo. Three cell lines (SNU-484, SNU-668, and SNU-719) showed various levels of increase in HER2 expression. Two cell lines showed minor to no changes in HER2 expression. NUGC-4 had consistent significant HER2 expression levels in both assays, while MKN-45 had consistent insignificant to no HER2 expression. Our study demonstrates inconsistency in HER2 gene expression between in vitro and in vivo cancer cell line models for the first time in gastric cancer.

Citation Format: Youme Gim, Hee Seo Park, Hae Rim Jung, Hae Ryung Chang, Seungyoon Nam, Yong Doo Choi, Ja-Lok Ku, Yon Hui Kim. Variability of HER2 expression between in vitro and in vivo models within gastric 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 2783. doi:10.1158/1538-7445.AM2014-2783
Abstract 2799: Adoptive immunotherapy for pediatric solid tumors with CAR-T cells (chimeric antigen receptor bearing T cells) targeting ALK (anaplastic lymphoma kinase, CD246)
Authors: Walker Alec , Lopomo Paola , Babbitt William , Vigny Marc , Mackall Crystal L. , Orentas Rimas J.
Published: May 2015

Neuroblastoma is the most common non-CNS tumor in children. High-risk disease has a dire prognosis and new treatment strategies are need. The identification of unique cell-surface proteins expressed on tumor cells, yet not expressed on normal tissues, has been challenging for pediatric malignancies. However, identification of such antigens allows for the development of new immune-based therapies featuring Ig-like binding motifs. The cell surface tyrosine kinase ALK (CD246, anaplastic lymphoma kinase) is a promising target for neuroblastoma in that it is expressed in either native, mutated, or over-expressed forms on the plasma membrane surface of the tumor cell and may contribute to disease progression or severity. We identified antibodies that bind to extracellular domains of ALK, sequenced their variable regions, and used this sequence information to construct chimeric antigen receptors (CARs). Primary human T lymphocytes were then transduced with retroviral gene vectors expressing a series of ALK-specific CAR. We tested CARs that incorporated both different structural and signaling motifs. Transduced T cells demonstrated ALK-specific cytolytic activity against ALK-expressing tumors and produced Th1 cytokines upon culture in the presence of tumor. In exploring different iterations of CAR domain structure we found that the scFv domains created from the heavy and light variable domains of ALK-specific immunoglobulin could be interchanged with respect to their orientation in the context of CAR tertiary protein structure. Moreover, ALK-specific scFv functioned whether expressed in a short format, that is as a single domain proximal to the T cell membrane, or in a long format, that is extended away from the plasma membrane using an IgG1-derived spacer domain composed of CH2 and CH3. Using a xenogeneic NSG mouse model for neuroblastoma, human ALK-specific CAR-expressing T cells were found to eradicate ALK-positive tumor, when IL-7 was included to support T cell persistence. These data argue for the continued evaluation of ALK-specific CARs in pre-clinical studies.

Citation Format: Alec Walker, Paola Lopomo, William Babbitt, Marc Vigny, Crystal L. Mackall, Rimas J. Orentas. Adoptive immunotherapy for pediatric solid tumors with CAR-T cells (chimeric antigen receptor bearing T cells) targeting ALK (anaplastic lymphoma kinase, CD246). [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 2799. doi:10.1158/1538-7445.AM2014-2799