bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 1608: CTC categorization: Subpopulations of CTCs and their potential clinical significance
Authors: Xue Chengsen , Mc Closkey Thomas W.
Published: August 2015

Circulating tumor cells (CTCs) were previously rare events difficult to identify. In clinical practice, CTC enumeration has now been recognized for its prognostic value. Furthermore, as CTC technology has rapidly improved, CTCs are now readily available for further investigation. The tumor cells isolated from CTC instruments may be analyzed for molecular profiles and mutation screening. Here we propose three new subsets of CTCs: elongated CTC (EL-CTC), miniature CTC (Mini-CTC) and cluster CTC (CL-CTC). Elongated CTC have an elongated shape and some of these cells have an enlarged tail composed of the nucleus. The enlarged tail is formed during intravasation because of the less flexible nuclear membrane and these cells represent highly motile tumor cells. The mini-CTCs are much smaller than regular tumor cells and may be dormant and gain the advantage of escaping immune surveillance. The CTC clusters are formed by a group of tumor cells and lymphocytes as well as macrophages. There is strong evidence that these clusters are highly malignant. These three subsets are recognized morphologically and their unique features may directly relate to their functionality and clinical significance. Additional investigation in the area of CTC research, specifically enhanced understanding of CTC subpopulations, may lead to novel therapeutic approaches in oncology.

Citation Format: Chengsen Xue, Thomas W. Mc Closkey. CTC categorization: Subpopulations of CTCs and their potential clinical significance. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1608. doi:10.1158/1538-7445.AM2015-1608
Abstract 1622: The AKT inhibitor reverses protein trafficking and inhibits tumor cell motility of p27-mislocalized osteosarcoma cells
Authors: Chen Xiang , Li Yiting , Nakka Manjula , Man Tsz Kwong
Published: August 2015

Osteosarcoma is the most common malignant bone tumor in children. The development of metastasis remains to be the leading cause of death in osteosarcoma. This clinical challenge urges the development of a novel therapeutic strategy to improve the survival of the metastatic patients. mTOR has recently been regarded as a potential target for metastatic osteosarcoma. However, because of its feedback loop in the pathway, it has become clear that inhibition of mTOR alone would not yield effective therapeutics. More importantly, it is still not clear if the mTOR upstream kinases phosphorylate other important molecules that can also promote metastasis. Our lab has recently demonstrated that a vast majority of osteosarcoma cases harbor cytoplasmic mislocalization of p27. p27 is a tumor suppressor gene that regulates normal cell cycle progression when it is localized in the nucleus. We and others have indicated that p27 acquires a new pro-metastatic function in the cytoplasm of osteosarcoma and other tumors. To evaluate if this observation has any therapeutic significance, our lab has created a set of p27 phosphomutants and found that specific phosphorylations (S10 and T198) are important for the pro-metastatic function in the cytoplasm. Furthermore, shRNA-mediated gene silencing experiments showed that knocking down the expression of p27 decreased the motility of metastatic LM7 cells. Since AKT, the upstream kinase of mTOR, has shown to phosphorylate p27, we tested if AKT inhibitors have any effect on the migration/invasion ability of three osteosarcoma cell lines (LM7, MG63 and G292) that harbor the p27 mislocalization. The results showed that both the AKT1/2 inhibitor and the PI3K/mTOR dual inhibitor PP242, but not mTORC1 inhibitor rapamycin, reduced the tumor cell migration/invasion ability. Interestingly, the inhibitors could also reverse the protein trafficking of p27 into the nucleus. These results suggest that the inhibitors may be able to inhibit the pro-metastatic function and restore the cell cycle inhibitory function of p27. Our long-term goal is to develop a precision medicine approach that will ultimately improve the outcome of metastatic osteosarcoma. By targeting the p27 mislocalization, we believe that we will develop a novel and clinically applicable therapeutic strategy that would eradicate metastatic osteosarcoma and improve the outcome of children affected by this tumor.

Citation Format: Xiang Chen, Yiting Li, Manjula Nakka, Tsz Kwong Man. The AKT inhibitor reverses protein trafficking and inhibits tumor cell motility of p27-mislocalized osteosarcoma cells. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1622. doi:10.1158/1538-7445.AM2015-1622
Abstract 1640: Exploiting the cytoskeletal filaments of neoplastic cells to potentiate a novel therapeutic approach
Authors: Trendowski Matthew
Published: August 2015

Although cytoskeletal-directed agents have been a mainstay in chemotherapeutic protocols due to their ability to readily interfere with the rapid mitotic progression of neoplastic cells, they are all microtubule-based drugs, and there has yet to be any microfilament- or intermediate filament-directed agents approved for clinical use. There are many inherent differences between the cytoskeletal networks of malignant and normal cells, providing an ideal target to attain preferential damage. Further, numerous microfilament-directed agents, and an intermediate filament-directed agent of particular interest (withaferin A) have demonstrated in vitro and in vivo efficacy, suggesting that cytoskeletal filaments may be exploited to supplement chemotherapeutic approaches currently used in the clinical setting. Therefore, this talk is intended to expose academics and clinicians to the tremendous variety of cytoskeletal filament-directed agents that are currently available for further chemotherapeutic evaluation. The mechanisms by which microfilament directed- and intermediate filament-directed agents damage malignant cells will be discussed in detail in order to establish how the drugs can be used in combination with each other, or with currently approved chemotherapeutic agents to generate a substantial synergistic attack, potentially establishing a new paradigm of chemotherapeutic agents.

Note: This abstract was not presented at the meeting.

Citation Format: Matthew Trendowski. Exploiting the cytoskeletal filaments of neoplastic cells to potentiate a novel therapeutic approach. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1640. doi:10.1158/1538-7445.AM2015-1640
Abstract 1643: Discovery of 1-benzylquinazoline-2,4(1H,3H)-diones as novel and potent PARP inhibitors. SAR of the benzyl group
Authors: Cai Sui Xiong , Xu Qingbing , Wu Lizhen , Yin Feng , Hu Xiuhua , Wang Xiaozhu , Jiang Yangzhen , Bao Qingli , Wang Guoxiang , Zhang Xiuyan , Tian Ye Edward
Published: August 2015

Poly (ADP-ribose) polymerase (PARP) is a key enzyme for DNA repair and PARP-1 inhibitors have been shown to be effective against cancers with DNA repair defects, such as BRCA1 or BRCA2 mutations. Recently, European Medicines Agency (EMA) recommended approval of PARP-1 inhibitor Olaparib (AZD2281) for the treatment of ovarian cancers with BRCA mutations.

In this presentation, we will report our discovery of a series of 1-benzylquinazoline-2,4(1H,3H)-diones (BQD) as novel and potent PARP inhibitors. We will present SAR data for substituents at the 3- and 4-positions of the benzyl group of BQD, and the identification of IMP4297 as a clinical candidate. IMP4297 has advantages in vitro and in vivo over AZD2281. It is not only more potent but also more selective than AZD2281 in cell-based assays, and was 20-fold more efficacious than AZD2281 in a BRCA1 mutated MDA-MB-436 human breast cancer xenograft model. IND enabling studies for IMP4297 is in progress with IND submission planned in 12 months.

Citation Format: Sui Xiong Cai, Qingbing Xu, Lizhen Wu, Feng Yin, Xiuhua Hu, Xiaozhu Wang, Yangzhen Jiang, Qingli Bao, Guoxiang Wang, Xiuyan Zhang, Ye Edward Tian. Discovery of 1-benzylquinazoline-2,4(1H,3H)-diones as novel and potent PARP inhibitors. SAR of the benzyl group. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1643. doi:10.1158/1538-7445.AM2015-1643
Abstract 1645: DNA-damaging compound 0404 effectively inhibits hepatocellular carcinoma by upregulation of miR-34a and miR-200c expression
Authors: Xia Caixia , Liu Yanning , Lou Guohua , Xu Xiao , Mao Long , Zheng Min
Published: August 2015

Hepatocellular carcinoma (HCC) is the sixth most common type of cancer and the third most common cause of cancer deaths worldwide. DNA-damaging agents have a long history of use in cancer chemotherapy. Unfortunately, chemotherapeutic treatment strategies against HCC are very ineffective. We have screened of a novel DNA-damaging compounds, 0404, by using time-dependent cellular response (TCRP) based on unique TCRP DNA-damage signature. This new compound could induce apoptosis effectively in hepatocellular carcinoma at nM-degree concentration. Since microRNAs (miRNAs) have been show play critical roles in pathogenesis of HCC, the present study was aimed to investigate the role of miRNAs in the anticancer effects of 0404. We found that, HepG2 cells, which retain wild-type p53, were more sensitive to 0404 treatment than Huh7 cells, which with mutant p53. At IC50 and IC99 concentration, 0404 upregulated the expression of miR-34a and miR-200c, two major miRNA regulated by p53, in a dose- and time-dependent manner in HepG2 cells. Western blot analysis further show that up-regulation of miR-34a decreased SIRT1 expression, leading to an increase in acetylated p53 levels and also an increase in p53 targets such as p21 and PUMA. In addition, up-regulation of miR-200c decreased the expression of EMT-inducing transcription factors ZEB1 and ZEB2, which play key role in tumor invasion and metastasis. Furthermore, miR-34a or miR-200c inhibitors impaired the down-regulation of miR-34a or miR-200c target genes, respectively, by 0404 treatment, and partially impaired the tumor suppression effect of 0404. These results suggest that 0404 may be an attractive agent in chemotherapy for HCC, especially in HCC with wt p53, by regulation of miR-34a and miR-200c.

Financial support: This study was supported by the National Natural Science Fund (81272679) and the Major national S&T Projects (2013ZX09041003).

Citation Format: Caixia Xia, Yanning Liu, Guohua Lou, Xiao Xu, Long Mao, Min Zheng. DNA-damaging compound 0404 effectively inhibits hepatocellular carcinoma by upregulation of miR-34a and miR-200c expression. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1645. doi:10.1158/1538-7445.AM2015-1645
Abstract 1659: The non-cardiotoxic anticancer drug pixantrone targets topoisomerase II
Authors: Hasinoff Brian B. , Wu Xing , Patel Daywin , Yalowich Jack C.
Published: August 2015

Pixantrone is a new non-cardiotoxic aza-anthracenedione anticancer drug structurally related to anthracyclines and anthracenediones such as doxorubicin and mitoxantrone. Pixantrone is approved in the EU for the treatment of relapsed or refractory aggressive B-cell non-Hodgkin lymphoma. This study was undertaken to investigate both the mechanisms of its anticancer activity and its lack of cardiotoxicity. The reduced cardiotoxicity of pixantrone compared to doxorubicin may be due to the fact that it did not bind iron(II) or iron(III). Thus, unlike doxorubicin it would not be able to induce iron-based oxidative stress in the heart. Pixantrone did, however, form a weak complex with Cu(II). Pixantrone was 10-fold less damaging to neonatal rat myocytes than doxorubicin as measured by LDH release. As measured by EPR spectrometry pixantrone generated about two-fold higher levels of its semiquinone free radical than doxorubicin in the hypoxanthine-xanthine oxidase reducing system. Conversely, in intact K562 cells under nitrogen, doxorubicin produced much more semiquinone radical than pixantrone. The reduced myocyte toxicity and semiquinone-forming ability in K562 cells compared to doxorubicin may be due low cell accumulation of dicationic pixantrone. Multidrug resistant Pgp- (ABCB1) overexpressing MDCK/MDR cells were 40-fold cross resistant to pixantrone, compared to parental cells. Pixantrone bound to DNA much more strongly than doxorubicin as determined in a DNA melting point assay. Pixantrone targeted topoisomerase II as evidenced by its ability to inhibit kDNA decatenation, to produce linear double-stranded DNA in a pBR322 DNA cleavage assay, and to form covalent topoisomerase II-DNA complexes in a cellular ICE assay. Pixantrone was 3-fold cross-resistant to K562-derived etoposide-resistant cells. DNA double strand breaks produced by pixantrone assessed in a cellular γH2AX assay were also characteristic of a topoisomerase II-targeted drug. These results support the conclusion that pixantrone displays characteristics that are consistent with targeting topoisomerase II. Support: CIHR; a Canada Research Chair in Drug Development; R01 CA090787.

Citation Format: Brian B. Hasinoff, Xing Wu, Daywin Patel, Jack C. Yalowich. The non-cardiotoxic anticancer drug pixantrone targets topoisomerase II. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1659. doi:10.1158/1538-7445.AM2015-1659
Abstract 167: Targeting non-coding RNAs with the CRISPR/Cas9 system in human cell lines
Authors: Ho Tsui-Ting , Zhou Nanjiang , Huang Jianguo , Koirala Pratirodh , Xu Min , Fung Roland , Wu Fangting , Mo Yin-Yuan
Published: August 2015

The clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated (Cas) system (CRISPR/Cas) has been recently shown to be a powerful genome-editing tool in a variety of organisms. However, these studies are mainly focused on protein-coding genes. The present study aims to determine whether this technology can be applied to non-coding genes. One of the challenges for knockout of non-coding genes is that a small deletion or insertion generated by the standard CRISPR/Cas system may not necessarily lead to functional loss of a given non-coding gene because of lacking an open reading frame, especially in polyploidy human cell lines. To overcome this challenge, we adopt a selection system that allows for marker genes to integrate into the genome through homologous recombination (HR). Moreover, we construct a dual guide RNA vector that can make two cuts simultaneously at designated sites such that a large fragment can be deleted. With these approaches, we are able to successfully generate knockouts for miR-21, miR-29a, lncRNA-21A, UCA1 and AK023948 in various human cell lines. Finally, we show that the HR-mediated targeting efficiency can be further improved by suppression of the non-homologous end joining pathway. Together, these results demonstrate the feasibility of knockout for non-coding genes by the CRISPR/Cas system in human cell lines.

Citation Format: Tsui-Ting Ho, Nanjiang Zhou, Jianguo Huang, Pratirodh Koirala, Min Xu, Roland Fung, Fangting Wu, Yin-Yuan Mo. Targeting non-coding RNAs with the CRISPR/Cas9 system in human cell lines. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 167. doi:10.1158/1538-7445.AM2015-167
Abstract 1671: Fibroblast growth factor receptor 3 enhances progression of hepatocellular carcinoma
Authors: Paur Jakob , Nika Lisa , Maier Christiane , Kostka Julia , Heffeter Petra , Kappel Sonja , Kandioler Daniela , Holzmann Klaus , Marian Brigitte , Berger Walter , Grusch Michael , Grasl-Kraupp Bettina
Published: August 2015

Purpose of the study. To provide mechanistic evidence that fibroblast growth factor receptor 3 (FGFR3) and its two splice variants, FGFR3-IIIb and -IIIc, impact considerably on the malignant phenotype of hepatocellular carcinoma (HCC).

Experimental procedures. The occurrence of FGFR3 and its two isoforms was analyzed in human HCC samples by qRT-PCR and immunostaining. In hepatoma/hepatocarcinoma cell lines FGFR3-isoforms were overexpressed by lentiviral constructs or were down-modulated by siRNA or an adenoviral kinase-dead FGFR3 (kdFGFR3) construct. Cell lines were tested for anchorage-independent growth, proliferation at low-densities and their cell-cycle distribution, as well as their ability to form tumors after subcutaneous injection into the flanks of SCID-mice.

Results. Upregulated FGFR3 was found in almost 50% of HCC patients, which was often due to the enhanced expression of FGFR3-IIIb. Furthermore, patients with FGFR3-IIIb overexpression showed early tumor recurrence indicating that this isoform may be a major player in tumor progression. In hepatoma/hepatocarcinoma cells, upregulated FGFR3-IIIb or FGFR3-IIIc conferred an enhanced capability for proliferation and tumor growth. Both isoforms enhanced downstream signaling and increased the cells’ ability to grow at low densities. The tumorigenicity of cells in SCID-mice was augmented more by variant IIIb than by IIIc. This stronger impact of FGFR-IIIb on cell proliferation could also be seen in analysis of the cell cycle distribution, which was shifted to the S-phase. Conversely, siFGFR3 and kdFGFR3 affected both receptor-variants and strongly reduced clonogenic growth at low density and anchorage-independent growth. Furthermore, kdFGFR3 arrested the cells in G2/M and strongly attenuated tumor formation in vivo.

Conclusions: Upregulated FGFR3 is associated with development and progression of hepatocellular carcinoma. Accordingly, blockade of FGFR3-mediated signaling may be a promising therapeutic approach to antagonize growth and malignant behavior of HCC cells.

Citation Format: Jakob Paur, Lisa Nika, Christiane Maier, Julia Kostka, Petra Heffeter, Sonja Kappel, Daniela Kandioler, Klaus Holzmann, Brigitte Marian, Walter Berger, Michael Grusch, Bettina Grasl-Kraupp. Fibroblast growth factor receptor 3 enhances progression of hepatocellular carcinoma. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1671. doi:10.1158/1538-7445.AM2015-1671
Abstract 1675: MEF2 plays a significant role in the tumor inhibitory effects of agarose encapsulated RENCA cells through the EGF receptor
Authors: Martis Prithy C. , Laramore Melissa A. , Dudley Atira , Smith Barry H. , Gazda Lawrence S.
Published: August 2015

Identification of the molecular targets involved in the tumor growth inhibition induced by agarose encapsulated mouse renal adenocarcinoma (RENCA) cells will aid in an understanding of the mechanism of action and may allow for the discovery of key targets for therapeutic intervention. The epidermal growth factor receptor (EGFR/ERBB1/HER1) and related family members have been shown to transduce extracellular signals through the mitogen-activated protein kinase (MAPK) pathway to regulate post-translational regulation of myocyte enhancer factor 2 (MEF2) proteins. We have previously reported that suppression of MEF2 isoforms in target tumor cells reduced the growth inhibitory effect of RENCA macrobeads. In this study, we evaluated signaling through EGFR in response to RENCA macrobead conditioned media and examined post-translational activation of MEF2D, using the human prostate cancer, DU145 and the human breast adenocarcinoma, MCF7 cell lines. DU145 and MCF7 cells exposed to naïve or conditioned media were evaluated using In-Cell Western™ analysis for the expression of phospho-EGFR Y1068 in parallel with total EGFR. Phospho-MEF2D and total MEF2D were assessed in nuclear extracts using western blotting. In the DU145 cells, exposure to RENCA macrobead conditioned media activates EGFR as evidenced by phosphorylation of the receptor at tyrosine 1068 in parallel with the increasing age and inhibitory capacity of macrobeads. Further, the growth inhibition of DU145 cells exposed to RENCA macrobead conditioned media is accompanied by dephosphorylation of MEF2D at Serine 444 supporting a role for increased MEF2D transcriptional activity in the inhibitory effect. MCF7 cells are less sensitive to RENCA macrobead-induced growth inhibition, EGFR is not phosphorylated by 2 hours following exposure to macrobead conditioned media and MEF2D remains phosphorylated at Serine 444. These findings support the hypothesis that RENCA macrobeads signal, at least in part, through the EGF receptor to differentially regulate MEF2D, which is significant for macrobead-induced tumor growth inhibition.

Citation Format: Prithy C. Martis, Melissa A. Laramore, Atira Dudley, Barry H. Smith, Lawrence S. Gazda. MEF2 plays a significant role in the tumor inhibitory effects of agarose encapsulated RENCA cells through the EGF receptor. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1675. doi:10.1158/1538-7445.AM2015-1675
Abstract 1678: Bioavailability and anti-tumor activity of capsaicin in human small cell lung cancer
Authors: Hurley John D. , Rollyson William D. , Stover Cody A. , Brown Kathleen C. , Perry Haley E. , Stevenson Cathryn D. , Crabtree Clayton M. , Dom Aaron M. , Lau Jamie K. , Witte Theodore R. , Hardman W E. , Dasgupta Piyali
Published: August 2015

The nutritional compound capsaicin has been shown to display anti-neoplastic activity in breast, prostate and colon tumors xenografted in nude mice. Based on these data from other research laboratories, we wanted to determine the bioavailability of capsaicin in nude mice in vivo. We found that capsaicin was rapidly metabolized primarily in the liver. The bioavailability of intact capsaicin was highest in the lung. Therefore, we hypothesized that capsaicin should suppress the growth of lung tumors. We found that capsaicin induced robust apoptosis in human SCLC cell lines. Capsaicin decreased the growth rates of human SCLC tumors in two in vivo models, namely the CAM model and the nude mouse model. HPLC studies showed intact capsaicin in the tumors excised from nude mice. The heat-sensation activity of capsaicin is mediated by the transient receptor potential vanilloid (TRPV) family of proteins. Capsaicin functions as an agonist of the TRPV1 receptor. The apoptotic activity of capsaicin was found to be mediated by TRPV6 and not TRPV1. Preliminary data shows that capsaicin increases the expression of the TRPV6 receptor, causing apoptosis in human SCLCs.

Citation Format: John D. Hurley, William D. Rollyson, Cody A. Stover, Kathleen C. Brown, Haley E. Perry, Cathryn D. Stevenson, Clayton M. Crabtree, Aaron M. Dom, Jamie K. Lau, Theodore R. Witte, W E. Hardman, Piyali Dasgupta. Bioavailability and anti-tumor activity of capsaicin in human small cell lung cancer. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1678. doi:10.1158/1538-7445.AM2015-1678
Abstract 1682: Development and activity of a novel antibody-drug conjugate for the treatment of P-cadherin expressing cancers
Authors: Menezes Daniel , Abrams Tinya J. , Karim Christopher , Tang Yan , Ying Chi , Miller Kathy , Fanton Christie , Ghoddusi Majid , Wang Zhen , Patawaran Montesa , Pryer Nancy , Lees Emma , Damiano Jason
Published: August 2015

The cell surface glycoprotein P-cadherin is an attractive target for an antibody-drug conjugate (ADC) therapy as it is known to be highly expressed in a number of malignancies, including those arising in the epithelium of the breast, lung, bladder, esophagus, stomach, endometrium and colon, among others. In breast cancer, P-cadherin is frequently overexpressed in high grade invasive tumors and is a reliable marker of the basal-like breast cancer molecular subtype, a disease with no effective therapeutic treatment options. Based on the expression profile of P-cadherin in human cancer, a highly selective and potent ADC was developed to target cancer types overexpressing this glycoprotein. This ADC consists of a fully human anti-P-cadherin-specific antibody conjugated to the potent maytansine-derived microtubule-disruptor, DM1, via an SMCC non-cleavable thioether linkage (technology licensed from ImmunoGen, Inc.). In vitro, the ADC was demonstrated to selectively bind P-cadherin expressing cell lines, to rapidly internalize and traffic to lysosomes, and to release a sufficient amount of activated payload to potently induce a cytotoxic response in cell viability assays. Profiling of activity in a cell line panel indicated that this ADC can effectively target and kill P-cadherin-positive cancer cells representing breast, head and neck, and bladder carcinomas. In vivo, the ADC was highly efficacious in numerous relevant xenograft models of P-cadherin expressing cancers, including breast, head and neck, bladder and lung. From this promising cellular and in vivo activity, this ADC may be an effective treatment for patients with P-cadherin positive cancers of high unmet medical need.

Citation Format: Daniel Menezes, Tinya J. Abrams, Christopher Karim, Yan Tang, Chi Ying, Kathy Miller, Christie Fanton, Majid Ghoddusi, Zhen Wang, Montesa Patawaran, Nancy Pryer, Emma Lees, Jason Damiano. Development and activity of a novel antibody-drug conjugate for the treatment of P-cadherin expressing cancers. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1682. doi:10.1158/1538-7445.AM2015-1682
Abstract 1683: Pharmacokinetic/pharmacodynamic (PK/PD) and toxicokinetic/toxicodynamic (TK/TD) modeling of preclinical data of FGFR2-ADC (BAY 1187982) to guide dosing in phase 1
Authors: Wittemer-Rump Sabine , Sommer Anette , Kopitz Charlotte , Huynh Hung , Schatz Christoph , Zierz Ruprecht , Braun Manuela , Meyer Kirstin , Laurent Dirk , Lippert Jörg , Prins Klaas
Published: August 2015

BAY 1187982 is an antibody drug conjugate (ADC) directed against fibroblast growth factor receptor 2 (FGFR2). FGFR2 is overexpressed in several cancer indications, such as gastric, breast, and ovarian cancer. Anti-tumor efficacy of BAY 1187982 has been demonstrated in several FGFR2-positive cancer cell line as well as patient-derived xenograft models. Toxicology findings from repeated dose preclinical safety studies in monkeys indicated effects related to the liver, kidney, heart and coagulation system. To predict the therapeutic index of BAY 1187982 in humans and to support the design of the first-in-human (FIH) study with respect to selection of dose and regimen, preclinical efficacy and toxicity findings were quantified. All available preclinical PK, TK, tumor response and toxicity data from mouse models and monkey studies were used to create a model framework to describe the PK, TK, PK/PD and TK/TD relationship as functions of BAY 1187982 dose, regimen and time. Human PK parameters based on scaling from monkey were used to predict PK profiles in humans for a range of doses and schedules. These sets of predicted exposure models were combined with the PK/PD as well as the TK/TD model to assess the expected efficacy (according to RECIST criteria) and toxicity range in humans, respectively. The dosing schedule leading to the largest therapeutic index and the dose escalation schema for the FIH study were determined. The FIH study is currently under preparation.

Citation Format: Sabine Wittemer-Rump, Anette Sommer, Charlotte Kopitz, Hung Huynh, Christoph Schatz, Ruprecht Zierz, Manuela Braun, Kirstin Meyer, Dirk Laurent, Jörg Lippert, Klaas Prins. Pharmacokinetic/pharmacodynamic (PK/PD) and toxicokinetic/toxicodynamic (TK/TD) modeling of preclinical data of FGFR2-ADC (BAY 1187982) to guide dosing in phase 1. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1683. doi:10.1158/1538-7445.AM2015-1683
Abstract 1696: Blocking activity of a novel anti-MET humanized monoclonal antibody, KTN0216, is enhanced by IgG2 isotype in HGF-dependent and Met-amplified tumors
Authors: Mandiyan Sreekala , Robinson Brett S. , Kimmel Lida , McMahon Gerald , Hadari Yaron , Yang Yan
Published: August 2015

Aberrant activation of MET kinase can be mediated by ligand-dependent mechanisms through paracrine or autocrine stimulation by its ligand, HGF, or by ligand-independent mechanisms through gene amplification, over-expression or mutation. Both mechanisms of activating MET have been associated with promoting tumor growth and progression. The discovery of antagonistic MET antibodies has been challenging as many anti-MET antibodies promote kinase activation that leads to cell proliferation and migration. We have systematically screened MET antibodies using cell based functional assays and identified a number of antibodies that potently block MET-dependent cell proliferation, cell scattering as well as tumor growth in vivo. One such antibody, KTN-MET-IgG1, binds to the Sema/PSI domain and prevents HGF-MET interaction; additionally it induces receptor ubiqutination and degradation. To evaluate if the IgG isotype influences activity on MET activation and tumor growth we grafted the binding domains of this antibody onto 2 other IgG backbones: KTN-MET-IgG2 and KTN-MET-IgG4. Surprisingly, grafting the antibody variable regions onto the IgG2 framework dramatically enhanced the anti-MET activity in vitro and in vivo. Comparing to KTN-MET-IgG1 and KTN-MET-IgG4 antibodies with KTN-MET-IgG2 antibody, it demonstrated significantly better inhibition of receptor phosphorylation and cell proliferation in MET amplified tumor cell lines (EBC1, SNU5) and comparable activity in HGF-dependent tumor cell lines (A549, U87MG). KTN-MET-IgG2 treatment of tumor bearing mice achieved potent and prolonged suppression of tumor growth using the U87MG glioblastoma xenograft model and tumor growth regression with tumors remaining below detection for over 90 days post last dosing using the SNU5 gastric cancer xenograft model. In summary, we have found a novel IgG2 anti-MET antibody that inhibits tumor growth driven by HGF-dependent MET activation and MET amplification. A model to help explain the contribution of IgG2 isotype to enhanced blocking activity will be presented. The humanized version of KTN-MET-IgG2, KTN0216, is currently in preclinical development to evaluate tumor types best suited for KTN0216 treatment.

Citation Format: Sreekala Mandiyan, Brett S. Robinson, Lida Kimmel, Gerald McMahon, Yaron Hadari, Yan Yang. Blocking activity of a novel anti-MET humanized monoclonal antibody, KTN0216, is enhanced by IgG2 isotype in HGF-dependent and Met-amplified tumors. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1696. doi:10.1158/1538-7445.AM2015-1696
Abstract 170: Survival prediction model with long non-coding RNA profile in lung adenocarcinoma cancer
Authors: Wang Wei-An , Lai Liang-Chuan , Tsai Mong-Hsun , Liu Tzu-Pin , Chuang Eric Y.
Published: August 2015

Long non-coding RNAs (LncRNA) are over 200 nucleotides bases non-protein-transcript RNA. Recently, there is a rapid growing literature about LncRNA. LncRNAs are considered as regulator of mRNA, structure components and precursor to small RNAs. However, the mechanism of LncRNA in tumor progression is still not clear yet. Previous studies has validated several LncRNA are associated with prostate cancer and breast cancer (e.g. MATAT-1, PCA3). Here, we investigate the LncRNA expression profile in lung adenocarcinoma cancer and predict patient survival with cox regression model.

We download the dataset GSE30219 on Gene Expression Omnibus, microarray data on Affymetrix U133-plus2 platform. With the LncRNA probes selection pipeline on U133-plus2 investigated by Du et al., total 2,427 probes are associated with LncRNA, and every LncRNA is targeted by at least four probes. It is believed that LncRNAs are subtype specific due to previous studies, so we first defined the differential expression LncRNA probes between Adenocarcinoma and Squamous cancer with student t-test, and selected the top 50 p-value probes. Next, with the profile of these 50 probes and the clinical data, we focus on survival analysis of Adenocarcinoma and cox regression was used to identify the survival related probes in the 50 probes, P-value < 0.05. Finally, the expression profiles of survival related probes were trained with cox regression again to build up a prediction model.

With score given by the prediction model, samples are divided into two groups: high-risk and low-risk when score higher than 0 or score under 0, respectively. The Kaplan-Meier curve was used to illustrate the relationship between two groups. By using GSE30219 as training model set, GSE30219 was used as internal-validation and GSE8894 was used as external validation. The result of internal-validation shows significantly different. The difference of two groups on external- validation shows, although not greatly as internal- validation, there is still exists a slightly differences.

To sum up, LncRNA profiles in Lung Adenocarcinoma might play a role in survival rate. However, further improvement of prediction model is needed since the risk ratio of each sample should be reported, not only the cox scores. Also the Adenocarcinoma specific LncRNA probes should be investigated to enhance the confidence of prediction model.

Citation Format: Wei-An Wang, Liang-Chuan Lai, Mong-Hsun Tsai, Tzu-Pin Liu, Eric Y. Chuang. Survival prediction model with long non-coding RNA profile in lung adenocarcinoma cancer. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 170. doi:10.1158/1538-7445.AM2015-170
Abstract 1703: A 3D tissue culture-based utra-high content screening platform that uses phenotypic profiling of cancer tissues to identify selective inhibitors of receptor tyrosine kinases
Authors: Price Leo S. , Booij Tijmen , Klop Maarten
Published: August 2015

3D tissue cultures provide a more physiologically relevant context for the screening of compounds, compared to 2D cell cultures. Cells cultured in 3D hydrogels also show complex phenotypes, increasing the scope for phenotypic profiling.

Here we describe a high-content screening platform that uses human micro-tissues cultured in 3D in standard 384 well assay plates to study the activity of biologically active molecules. Image analysis tools were developed to process 3D image data to measure 854 phenotype-derived parameters. Multiparametric analysis was used to evaluate the effect of compounds on tissue morphology.

We applied this screening platform to measure the activity and selectivity of inhibitors of the c-Met and EGF receptor (EGFR) tyrosine kinases in 3D cultured prostate carcinoma cells. c-Met and EGFR activity was quantified based on the invasive phenotypic profiles induced by their respective ligands, HGF and EGF, which were added in parallel assays. c-Met and EGFR inhibitors generally showed the expected inhibitory profile equivalent to that obtained in the absence of cognate ligand. However, one phase-III c-Met inhibitor, displayed an unexpected phenotypic profile characterised by potent inhibition of tumour cell invasion and off-target effects consistent with a previously reported polypharmacology of this compound. The screening method was applied to a novel collection of 70 bi-specific compounds designed to target both c-Met and EGFR. Compounds were identified that induced phenotypic profiles indicative of selective inhibition of either c-Met, EGFR or both targets.

In conclusion, this poster describes a fully scalable high-content screening platform that uses phenotypic profiling to evaluate receptor tyrosine kinase inhibitor selectivity and activity in a physiologically relevant setting.

Citation Format: Leo S. Price, Tijmen Booij, Maarten Klop. A 3D tissue culture-based utra-high content screening platform that uses phenotypic profiling of cancer tissues to identify selective inhibitors of receptor tyrosine kinases. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1703. doi:10.1158/1538-7445.AM2015-1703
Abstract 1717: Selective induction of breast adenocarcinoma cell death via inhibition of the transient receptor potential melastatin-2 (TRPM2) cation channel
Authors: Koh David W. , Powell Daniel P. , Blake Steven D. , Hoffman Joy L. , Feng Xiaoxing
Published: August 2015

Transient receptor potential melastatin-2 (TRPM2) is a plasma membrane cation channel with important physiologic roles in noncancerous cells. However, in MCF-7 and MDA-MB-231 human breast adenocarcinoma cells, we previously demonstrated that TRPM2 was present in the nucleus, and pharmacologic inhibition or RNAi silencing of TRPM2 led to decreased proliferation. In this study, we evaluated the ability of TRPM2 inhibition to produce cell death in normal breast epithelial cells and breast adenocarcinoma cells. Further, we analyzed the cell death pathways induced. Treatment with the DNA alkylating agent, N-methyl-N’-nitro-N-nitrosoguanidine (MNNG), or doxorubicin (Dox) led to increased levels of cell death in MDA-MB-231 breast adenocarcinoma cells pretreated with TRPM2 inhibitors, but not in noncancerous mammary epithelial cells after pretreatment. Similar increases in cell death were observed after RNAi silencing of TRPM2 in both MDA-MB-231 and MCF-7 breast adenocarcinoma cells after Dox or tamoxifen treatment, respectively. Investigation of apoptosis after TRPM2 inhibition demonstrated decreased levels of caspase activity and no significant effect of Q-VD-OPh, a pan-caspase inhibitor, on cell death induced by TRPM2 inhibition. Further, pretreatment with 3-methyl adenine, an inhibitor of autophagy, also produced no significant effect on cell death induced by TRPM2 inhibition. These studies indicate that apoptosis or autophagy are not the primary cell death pathways induced by TRPM2 inhibition in breast cancer cells. Also, RNAi silencing of poly(ADP-ribose) glycohydrolase (PARG) and apoptosis-inducing factor (AIF), two proteins involved in initiating or facilitating alternative pathways of cell death, produced minimal changes in cell death induced by TRPM2 inhibition. Taken together, this study demonstrated that TRPM2 inhibition selectively increases cell death in breast adenocarcinoma cells. Further, the data suggests that apoptosis, autophagy, and PARG/AIF-mediated cell death are not the primarily cell death pathways involved in the cytotoxicity caused by TRPM2 inhibition. The results therefore suggest that TRPM2 is a potential target in breast cancer, where its inhibition may cause the selective eradication of breast adenocarcinoma cells.

Citation Format: David W. Koh, Daniel P. Powell, Steven D. Blake, Joy L. Hoffman, Xiaoxing Feng. Selective induction of breast adenocarcinoma cell death via inhibition of the transient receptor potential melastatin-2 (TRPM2) cation channel. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1717. doi:10.1158/1538-7445.AM2015-1717
Abstract 1721: Moving beyond in vitro models and addressing the challenges of pooled RNAi screens in mouse xenografts
Authors: Diehl Paul , Tedesco Donato , Bonneau Kyle , Makhanov Mikhail , Deng Debbie , Sun Peiqing , Chenchik Alex
Published: August 2015

RNAi loss-of-function screening with pooled shRNA expression libraries has proven to be a useful tool to identify essential cancer genes and drug resistance mechanisms in numerous cell lines in vitro. The effects of knocking down large numbers of genes on cancer cell growth and viability can be measured simultaneously using this approach. Now there is considerable interest to adapt RNAi viability screens to ex vivo xenograft mouse models. However, small take rates, growth rate variance of cells, and differing cell microenvironments in these more complex tumor models impose significant challenges to this sort of assay. We have developed a novel approach based on the use of pooled shRNA libraries with clonal barcodes that enables proliferation measurements of clonal populations produced by the individual shRNA-expressing founder cells that produce the tumor. This RNAi clonal analysis provides a basis to separate, across large cell populations, the external parameters that strongly influence cell growth rates from shRNA-induced growth inhibition in these systems. We will present in vivo RNAi screening validation data for several cancer models.

Citation Format: Paul Diehl, Donato Tedesco, Kyle Bonneau, Mikhail Makhanov, Debbie Deng, Peiqing Sun, Alex Chenchik. Moving beyond in vitro models and addressing the challenges of pooled RNAi screens in mouse xenografts. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1721. doi:10.1158/1538-7445.AM2015-1721
Abstract 1726: CRM1 is overexpressed in lung tumorigenesis and represents an adjuvant target for lung cancer treatment
Authors: Gao Weimin , Lu Chuanwen , Chen Lixia , Keohavong Phouthone
Published: August 2015

In spite of extensive investigations, the molecular mechanisms of lung tumorigenesis have not been completely understood, and the effective therapy for lung cancer is in great demand. Studies have shown that chromosome region maintenance 1 (CRM1), a nuclear export receptor for various cancer-associated ‘cargo’ proteins, overexpressed in several human cancers. The objectives of the present study are to evaluate the involvement of CRM1 in lung carcinogenesis and lung cancer treatment. First, we have analyzed the importance of CRM1 overexpression in lung cancer development. We showed that CRM1 was overexpressed in lung tumor tissues from lung cancer patients and lung adenocarcinoma in mice induced by a tobacco carcinogen, as well as lung cancer cell lines. The increased CRM1 expression levels in these lung cancer tissues and cells were associated with an increased phosphorylation level at threonine residue 55 of the p53 protein. Furthermore, CRM1 overexpression in lung cancer cells seemed to be p53-dependent. Stable overexpression of CRM1 in BEAS-2B cells led to malignant cellular transformation and p53 cytoplasmic localization. Moreover, as compared to A549 cells, cancer-related genes significantly altered in A549 cells with stable CRM1 knockdown. Second, we have evaluated targeting CRM1 as an adjuvant therapy for lung cancer treatment using both in vitro and in vivo models. We found that CRM1-siRNA could inhibit A549 cell growth and A549 cells with stable CRM1 knockdown showed more pronounced cytotoxic effects to cisplatin than A549 cells. In addition, A549 cells treated with cisplatin and a low non-toxic dose of leptomycin B (a CRM1 inhibitor) had a remarkably enhanced cytotoxicity compared to cisplatin. This increased therapeutic effect from leptomycin B and cisplatin was further validated using an in vivo xenograft mouse model. The findings of this study reveal the significance of CRM1 in lung carcinogenesis and lung cancer adjuvant therapy.

Citation Format: Weimin Gao, Chuanwen Lu, Lixia Chen, Phouthone Keohavong. CRM1 is overexpressed in lung tumorigenesis and represents an adjuvant target for lung cancer treatment. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1726. doi:10.1158/1538-7445.AM2015-1726
Abstract 1729: Discovery of a synthetic small molecule inhibitor of HSP90 for cancer therapy
Authors: Bao Rudi , Pan Zhongzong , Zhao Zhiming , Yu Hongping , Xu Yaochang
Published: August 2015

HSP90 is a major heat shock protein involved in the proper folding of its client proteins including many onco-proteins. HSP90 is elevated in tumor cells with a more active configuration, making it a potential target for cancer drug development. Utilizing structure-base design, we discovered a small molecule compound that inhibits HSP90 activity with an IC50 at low- nanomolar concentration. Cell proliferation was inhibited by this compound at a IC50 of single-digit nanomolar concentration across many different cancer cell lines. Mechanism of action studies demonstrated that this compound could induce HER-2 degradation in the breast cancer cell line BT-474 in vitro at concentrations between 100-300 nM. The compound showed an ideal pharmacological kinetic feature of less exposure and fast clearance in rat retina after intravenous administration, thus reducing the possibility of ocular toxicity as demonstrated by some other earlier HSP90 inhibitors. The compound also caused tumor growth inhibition in the xenograft tumor models, correlating with its target inhibition activity in these tumors. These data supports further development of this compound as a cancer therapeutic agent.

Citation Format: Rudi Bao, Zhongzong Pan, Zhiming Zhao, Hongping Yu, Yaochang Xu. Discovery of a synthetic small molecule inhibitor of HSP90 for cancer therapy. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1729. doi:10.1158/1538-7445.AM2015-1729