bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 26: MUC1 enhances neuropilin-1 signaling in pancreatic ductal adenocarcinoma
Authors: Zhou Ru , Curry Jennifer , Grover Priyanka , Roy Lopamudra Das , Leung TinChung , Mukherjee Pinku
Published: May 2015

Pancreatic ductal adenocarcinoma (PDA) has the worst prognosis of all cancers and is the 4th leading cause of cancer-related deaths in the United States. Mucin1 (MUC1) is a transmembrane glycoprotein over-expressed in more than 60% of PDA and its expression correlates with high metastases and poor prognosis. In PDA, there is a correlation between blood vessel density, tumor levels of VEGF, and disease progression. We have recently discovered a novel association between MUC1 and neuropilin-1 (NRP-1) expression. Neuropilin-1 (NRP-1) is a co-receptor for VEGF165 and blockade of NRP-1-VEGF165 interaction has been shown to inhibit angiogenesis and tumor growth in several other cancer types. Thus, we hypothesize that MUC1 induces a pro-angiogenic tumor microenvironment by increasing levels of VEGF and NRP-1, thus enhancing disease progression and metastases. We have generated Muc1-expressing KC and Muc1-null KCKO mouse PDA cell lines for this study. Compared to KCKO, KC cells secrete more VEGF and express higher levels of NRP-1 as well as VEGF receptors (1/2/3). Although the cell culture supernatants from KC do not alter the NRP-1 level on the endothelial line 2H11 cells, they significantly promote the 2H11 cell tube formation. Consistent with the in vitro results, tumor lysates from KC-bearing mice have higher levels of NRP-1 and VEGFR2 and its phosphorylations at Tyr residues 951, 996, and 1175. In human PDA cell lines, inhibition of MUC1 expression by specific siRNA reduced NRP-1 level while overexpression of full-length MUC1 increases NRP-1 expression. This suggests a direct regulation of NRP-1 by MUC1. Furthermore, the over-expression of MUC1 in BxPC3 human PDA cell line induces strong angiogenesis and promotes tumor metastasis in a zebrafish tumor xenograft model. Finally, we report that inhibition of NRP-1 by its specific blocking peptide suppresses BxPC3.MUC1 tumor growth in vivo. Taking together, MUC1 in PDA cells can enhance their own NRP-1 levels and promote the VEGF-VEGFR-NRP-1 signaling, which may favor the creation of a pro-angiogenic microenvironment for tumor growth and metastases. Our findings highlight the potential for MUC1 targeted blockade of VEGF-NRP-1 interaction in PDA by conjugating the NRP-1 inhibitory agents to a MUC1 targeting antibody.

Citation Format: Ru Zhou, Jennifer Curry, Priyanka Grover, Lopamudra Das Roy, TinChung Leung, Pinku Mukherjee. MUC1 enhances neuropilin-1 signaling in pancreatic ductal adenocarcinoma. [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 26. doi:10.1158/1538-7445.AM2014-26
Abstract 2612: ljm716, an anti her3 antibody that inhibits her3 dimerization, displays anti-tumor activity in esophageal squamous cell cancer
Authors: Sheng Qing , Wang Hui-Qin , das rita , chen yan , liang jinsheng , Xu Fiona , Wang zongyao , Cao Z. Alexander , Wang youzhen , huang alan
Published: May 2015

Background: Esophageal cancer is the eighth most common cancer and the sixth most common cause of cancer related death in the world. Squamous cell carcinoma is the predominant histologic subtype of esophageal cancer, particularly in Asia. Currently, no targeted therapy has been approved for treating this type of disease. Platinum-based combination chemotherapy remains to be the standard care for first line treatment of advanced or metastatic esophageal cancer with limited efficacy. Activation of EGFR/HER3/PI3K pathway is frequently observed in esophageal cancer, however, their therapeutic value remains to be further tested.

Methods: In this study, we evaluated the anti-tumor activity of LJM716, a fully human anti-HER3 antibody, either alone or in combination with anti-EGFR antibody cetuximab or PI3K alpha subunit inhibitor BYL719 in esophageal squamous cancer. LJM716, cetuximab and BYL719 single agent as well as their pair-wised combination activity were assessed in 24 esophageal squamous cancer cell (ESCC) lines using the CellTiter-Glo® Luminescent Cell Viability Assay. Single agent and combination anti-tumor activities of these reagents were also tested in selected cell line xenograft and patient derived xenograft mouse models.

Results: NRG1 expression (60%), PIK3CA mutation (8%), moderate PIK3CA (30%) and EGFR (30%) amplification were detected in a panel of 24 ESCC lines. Anti-HER3 antibody LJM716 potently inhibited HER3 phosphorylation and decreased pAKT level in these cell lines. In vitro, LJM716 inhibited proliferation of a sub-set of ESCC lines. LJM716 further enhanced and broadened the anti-tumor activities of both BYL719 and cetuximab in ESCC lines. In mouse xenograft models, LJM716 single agent treatment induced tumor stasis while combination with either BYL719 or cetuximab induced model dependent tumor regression.

Conclusion: NRG1-HER3-PI3K pathway activation is commonly observed in esophageal squamous cell cancer. Activation of HER3 is a potential mechanism leading to resistance to EGFR or PI3K targeted therapies, and combining anti-HER3 therapies with therapies targeting PI3K/EGFR may provide new therapeutic strategy for patients with esophageal squamous cell cancer.

Citation Format: Qing Sheng, Hui-Qin Wang, rita das, yan chen, jinsheng liang, Fiona Xu, zongyao Wang, Z. Alexander Cao, youzhen Wang, alan huang. ljm716, an anti her3 antibody that inhibits her3 dimerization, displays anti-tumor activity in esophageal squamous cell 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 2612. doi:10.1158/1538-7445.AM2014-2612
Abstract 2615: Novel combination therapy of adenoviral gene transfer of HER2-extracellular domain and trastuzumab-based photoimmunotherapy for HER2 negative cancer cells
Authors: Ishida Michihiro , Kagawa Shunsuke , Shimoyama Kyoko , Takehara Kiyoto , Noma Kazuhiro , Tanabe Shunsuke , Tazawa Hiroshi , Matsuoka Junji , Kobayashi Hisataka , Fujiwara Toshiyoshi
Published: May 2015

Introduction: Humanized anti-HER2 monoclonal antibody, trastuzumab, has provided survival benefit to patients with HER2 positive breast cancer and advanced gastric cancer. However, the treatment with trastuzumab was limited due to low or heterogeneous HER2 positivity, insufficient effects as single agent and acquisition of resistance. To overcome these problems, we employed the adenoviral vector expressing HER2-extracellular domain (HER2-ECD), Ad/ HER2-ECD, which is designed to tag cancer cells with HER2-ECD and to sensitize them to trastuzumab, and a novel photoimmunotherapy (PIT). PIT consists of trastuzumab-conjugated with a photosensitizer, IR700 (Tmab-IR700) and irradiation with near-infrared light, induces a strong cytotoxicity on HER2 positive cancer cells. We assessed the effect of Ad/HER2-ECD and Tmab-IR700 mediated PIT in HER2 negative cancer cells.

Methods: HER2 negative breast cancer cells (MCF7, MDA-MB-231) and gastric cancer cells (MKN1 and MKN45) were infected with Ad/ HER2-ECD. They were treated with Tmab-IR700 mediated PIT. We evaluated the HER2-ECD expression induced by Ad/ HER2-ECD and the cytotoxic effects of Tmab-IR700 mediated PIT.

Results: Ad/HER2-ECD efficiently expressed HER2 protein on the surface of the cancer cells. HER2-ECD expressing cells were selectively and rapidly killed by Tmab-IR700 mediated PIT, which was morphologically captured as bleb formation of cellular membrane.

Conclusions: We demonstrated that Ad/ HER-ECD combined with Tmab-IR700 mediated PIT could induce target-selective, immediate cell death in HER2 negative cancer cells. The combination therapy of adenoviral gene transfer of HER2-ECD and the molecular-target PIT is effective for cancer cells regardless of HER2 expression.

Citation Format: Michihiro Ishida, Shunsuke Kagawa, Kyoko Shimoyama, Kiyoto Takehara, Kazuhiro Noma, Shunsuke Tanabe, Hiroshi Tazawa, Junji Matsuoka, Hisataka Kobayashi, Toshiyoshi Fujiwara. Novel combination therapy of adenoviral gene transfer of HER2-extracellular domain and trastuzumab-based photoimmunotherapy for HER2 negative cancer 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 2615. doi:10.1158/1538-7445.AM2014-2615
Abstract 2619: Meausuring PIP3 reveals the unexpected role of p110B in luminal breast cancers
Authors: Costa Carlotta , Ebi Hiromichi , Faber Anthony C. , Nishtala Madhuri , Song Youngchul , Benes Cyril H. , Engelman Jeffrey A.
Published: May 2015

The phosphatidylinositol 3-kinase (PI3K) family of lipid kinases plays a prominent role in the growth and survival of several types of cancer, including breast cancers where the PI3K pathway is altered in up to 70% of cases. Due to the technical challenges of measuring the PI3K product, PIP3 directly, the phosphorylation of the downstream effector AKT has historically been used to indirectly assess the activity of class I PI3K. While this approach has proven to be rather useful, it is based on the assumption that this readout is proportional to the levels of PIP3, which is likely to apply only to a limited range of activation levels and within specific contexts. Indeed, evaluation of the efficacy of PI3K inhibitors with such indirect measurements may approximate and oversimplify the complex transduction mechanism of PI3K. During time course experiments using the p110A selective inhibitor, BYL719, we observed that both PIP3 and p-AKT levels were similarly restored after 24 hours in HER2 amplified breast cancer cells, while the rebound of p-AKT was minimal and did not correlate with increased PIP3 levels in PIK3CA mutant breast cancer models. Both p110B inhibition and p110B depletion were effective in blocking the PIP3 rebound observed. Consistent with this, the combination of p110A and p110B inhibitors decreased cell growth and induced a better apoptotic response compared to BYL719 alone. We further demonstrated that only the combination of p110A and p110B inhibitors induced tumor regression. Importantly, PIP3 levels correlated with efficacy more reliably than p-AKT in a PIK3CA mutant model in vivo. These data suggest that measurement of PIP3 levels following treatment may serve as a more effective biomarker than p-AKT levels to predict response to PI3K inhibitors within this subset of breast cancers.

Citation Format: Carlotta Costa, Hiromichi Ebi, Anthony C. Faber, Madhuri Nishtala, Youngchul Song, Cyril H. Benes, Jeffrey A. Engelman. Meausuring PIP3 reveals the unexpected role of p110B in luminal breast cancers. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 2619. doi:10.1158/1538-7445.AM2014-2619
Abstract 262: The PROFILE feasibility study: Genetic prostate cancer risk stratification for targeted screening
Authors: Eeles Rosalind , Kote-Jarai Zsofia , Antoniou Antonis , Kumar Pardeep , Mikropoulos Christos , Dadaev Tokhir , Taylor Natalie , Bancroft Elizabeth
Published: May 2015

Introduction & Objectives: Prostate cancer (PC) screening is controversial and a better assessment of individualized PC risk is needed. Several single nucleotide polymorphisms (SNPs) conferring a cumulative risk of PC have been identified. We have explored the potential role of genetic markers for targeted screening in a population with increased risk of PC due to family history (FH).

Material & Methods: PROFILE was developed as a pilot study to determine the feasibility of targeted PC screening using prostatic biopsy (PB) and its association with specific genetic profiles in men with FH. We also evaluated the role of PSA and Diffusion Weighted MRI (DW-MRI) as screening tools. 116 men aged 40-69 with FH of PC were enrolled between October 2009 and December 2012. Cumulative SNP risk scores were calculated by summing 59 risk alleles for each locus using the weighted effect (log-additive model). DW-MRI was performed in 50 patients. Participants were asked to undergo a 10 core PB regardless of baseline PSA.

Results: Median age 53 yrs (40-69) and median PSA was 1.15. One hundred and two men accepted to undergo a PB as primary PC screening. Twenty-three tumours were found (22.5% of biopsies) as well as seven men diagnosed with atypical small acinar proliferation (ASAP) (6.8%) and 8 men with high-grade prostatic intraepithelial neoplasia (HG-PIN) (7.8%). In total 37.1% received an abnormal result. Of those diagnosed with PC, 41% were intermediate or high risk and required treatment (compared to 24% in general population screening). The predictive performance of DW-MRI, PSA, genetic model and genetic model plus PSA measured by AUC were: 0.85, 0.73, 0.57 and 0.74, respectively. The genetic model performed best in men with a ‘normal’ PSA (<3 ng/ml - AUC 0.63). Analyses of a 78 SNP profile incorporating the new 23 recently identified SNPs is underway.

Conclusions: Our results indicate that PB used for PC screening in men with FH of PC identified a higher proportion of clinically significant PCs. The high AUC for DW-MRI would warrant a larger study. The incidence of ASAP is higher in this group than the general population.The SNP risk score was more predictive in men with PSA<3 where PB would not normally be undertaken, therefore an expanded study to investigate the role of genetic profiling in directing PB in PC screening is indicated.

Citation Format: Rosalind Eeles, Zsofia Kote-Jarai, Antonis Antoniou, Pardeep Kumar, Christos Mikropoulos, Tokhir Dadaev, Natalie Taylor, Elizabeth Bancroft. The PROFILE feasibility study: Genetic prostate cancer risk stratification for targeted screening. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 262. doi:10.1158/1538-7445.AM2014-262
Abstract 2623: PI3K/mTOR dual inhibitor PF-5212384 inhibits aberrant NF-kB activation and exhibits activity in combination with MEK inhibitor PD-325901 and docetaxel in human head and neck squamous cell carcinoma
Authors: Mohan Suresh , Broek Robert J. Vander , Saleh Anthony D. , Pierce Matthew L. , Coupar Jamie F. , Eytan Danielle F. , Chen Zhong , Waes Carter Van
Published: May 2015

Head and neck squamous cell carcinoma (HNSCC) is the sixth most common cancer worldwide, and standard treatment with surgery or chemoradiation has significant morbidity, with 5 year survival of <50%. Personalized targeted therapies with small molecule inhibitors have gained interest following identification of genetic drivers from The Cancer Genome Atlas (TCGA). TCGA data shows >60% of head and neck tumors harbor genomic alterations in the RTK-PI3K-mTOR and MAPK pathways important in cell growth and survival. In this study, we determined the effects of the novel PI3K-mTOR inhibitor PF-5212384 (PF-384) on molecular targets and HNSCC growth in preclinical models. PF-384 IC50s of 0.75nM-133nM were found in 12 HNSCC lines by XTT cell density assays and treatment resulted in increased sub-G0 cell death and G0/G1 phase blockade by DNA flow cytometry. PF-384 strongly inhibited direct targets of PI3K-mTOR, aberrant NF-kB transactivation and induced cytokines, but only partially inhibited MEK pathway targets. Transient siRNA knockdown of PIK3CA inhibited NF-kB activity, supporting PI3K-mTOR as an important driver and target for inhibition of NF-kB prosurvival signaling in HNSCC. PF-384 partially inhibited UMSCC1 tumor xenografts in vivo. PF-384 with MEK inhibitor PD-325901 or docetaxel revealed combinatorial activity. Given the high proportion of HNSCC patients with aberrations in the PI3K pathway and combinatorial activity observed, PF-384 with PD-901 or docetaxel merit further investigation in HNSCC.

Supported by NIH Medical Research Scholars Program (SM, RVB, DFE) and NIDCD intramural projects ZIA-DC-000016, 73 and 74 (AS, JC, ZC, CVW).

Citation Format: Suresh Mohan, Robert J. Vander Broek, Anthony D. Saleh, Matthew L. Pierce, Jamie F. Coupar, Danielle F. Eytan, Zhong Chen, Carter Van Waes. PI3K/mTOR dual inhibitor PF-5212384 inhibits aberrant NF-kB activation and exhibits activity in combination with MEK inhibitor PD-325901 and docetaxel in human head and neck squamous cell carcinoma. [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 2623. doi:10.1158/1538-7445.AM2014-2623
Abstract 2625: Increased sensitivity to Wnt/beta-catenin inhibitors in hepatocellular carcinoma cells harboring activating mutation of beta-catenin
Authors: Lin Hsiao-Hui , Feng Wen-Chi , Lu LI-Chun , Hsu Ta-Wen , Cheng Ann-Lii , Hsu Chih-Hung
Published: May 2015

[Background] The WNT/β-catenin signaling pathway is a major oncogenic pathway of human hepatocellular carcinoma (HCC). More than 50% of HCCs have aberrant activation of WNT/β-catenin signaling, which are caused by genetic alterations, ligand activation, or cross-activation by other signaling pathways. We hypothesized that activating mutation of CTNNB1, the coding gene of β-catenin, may confer sensitivity to WNT/β-catenin inhibitors in HCC cells.

[Materials and Methods] SNU398 is a human HCC cell line harboring a missense somatic mutation in exon 3 of CTNNB1 gene, resulting in S37C mutation. Huh7, HepG2, PLC5, and Hep3B are HCC cells containing no somatic mutations in exon 3 of CTNNB1 gene. HCC cells were treated with various types of WNT/β-catenin pathway inhibitors, including ICG-001 which down-regulates β-catenin/TCF transcriptional activity by interfering the binding of β-catenin with its transcriptional activation complex, XAV939 which targets tankyrases and facilitates degradation of β-catenin, and LGK974 which inhibits Porcupine, an acyltransferase responsible for palmitoylation and secretion of Wnt ligands, and evaluated for in vitro viability by MTT.

[Results] ICG-001 as a single agent showed significantly greater anti-proliferation effect in SNU398 than other HCC cells. The 50%-inhibitory concentrations (IC50s) of ICG-001 were 5 μM and >10 μM for SNU398 and other HCC cells, respectively. ICG-001 also induced a more potent suppression of colony- formation, and a more significant increase of subG1 fraction detected by flow cytometry in SNU398 cell than other HCC cells. XAV939 up to 20 μM induced only modest anti-proliferative effect in all HCC cells. However, SNU398 remained the one showing the greatest sensitivity to the growth suppression induced by XAV939. The anti-proliferative effect of LGK974 was modest and showed no significant difference among different HCC cells.

[Conclusion] The activating mutation of β-catenin may confer sensitivity to certain WNT/β-catenin pathway inhibitors, such as ICG-001, in HCC cells. (This study was supported by grants NRPB-100CAP1020-2).

Citation Format: Hsiao-Hui Lin, Wen-Chi Feng, LI-Chun Lu, Ta-Wen Hsu, Ann-Lii Cheng, Chih-Hung Hsu. Increased sensitivity to Wnt/beta-catenin inhibitors in hepatocellular carcinoma cells harboring activating mutation of beta-catenin. [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 2625. doi:10.1158/1538-7445.AM2014-2625
Abstract 2632: Casein kinase II inhibitors regulate cell cycle progression in leukemia
Authors: Gowda Chandrika , Song Chunhua , Sachdev Mansi , Pan Xiaokang , Ding Yali , Payne Kimberley , Dovat Sinisa
Published: May 2015

Casein Kinase II (CK2) is an oncogenic kinase that is overexpressed in leukemia. The molecular mechanism by which CK2 exerts its oncogenic function is largely unknown. We have previously demonstrated that CK2 directly phosphorylates the Ikaros tumor suppressor in vivo at multiple, evolutionarily conserved amino acids. CK2-mediated phosphorylation of Ikaros results in reduced DNA binding affinity, loss of pericentromeric localization and impaired Ikaros transcriptional repression. We hypothesize that the pro-oncogenic activity of CK2 in leukemia involves functional inactivation of Ikaros, and that CK2 inhibition will result in restoration of the tumor suppressor function of Ikaros and an anti-leukemia effect. To test this hypothesis, we have tested the effect of specific CK2 inhibitors on Ikaros function as a transcriptional regulator of genes that promote cell cycle progression. Using quantitative Chromatin Immunoprecipitation (qChIP), we have shown that Ikaros binds to the promoters of two genes that are essential for mitosis, ANAPC1 and ANAPC7, in leukemia cell lines and in primary leukemia cells. Increased expression of Ikaros via retroviral transduction was associated with increased binding of Ikaros to the promoters of ANAPC1 and ANAPC7 and their transcriptional repression. Luciferase reporter assay was used to confirm that Ikaros can directly repress transcription of both ANAPC1 and ANAPC7. These data suggest that Ikaros negatively regulates cell cycle progression during mitosis and that Ikaros function as a repressor of ANAPC1 and ANAPC7 is impaired in leukemia. We tested the ability of CK2 inhibition to restore Ikaros repressor activity in leukemia. We evaluated the pre-B acute lymphoblastic leukemia (B-ALL) cell line, Nalm6 treated with a specific CK2 inhibitor, TBB as well as in a murine preclinical xenograft model of B-ALL. CK2 treatment resulted in increased Ikaros binding to promoters of ANAPC1 and ANAPC7, along with transcriptional repression of both genes. This was associated with prolonged survival of B-ALL xenograft mice that were treated with CK2 inhibitors. These data suggest that CK2 inhibitors can regulate cell cycle progression in leukemia cells by restoring the transcriptional repressor function of Ikaros. Our results demonstrate efficacy of CK2 inhibitors as a novel treatment for leukemia.

Citation Format: Chandrika Gowda, Chunhua Song, Mansi Sachdev, Xiaokang Pan, Yali Ding, Kimberley Payne, Sinisa Dovat. Casein kinase II inhibitors regulate cell cycle progression in leukemia. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 2632. doi:10.1158/1538-7445.AM2014-2632
Abstract 2633: TP53 loss creates therapeutic vulnerability in cancer
Authors: Liu Yunhua , Lu Xiongbin
Published: May 2015

TP53, a well-known tumor suppressor gene, is frequently inactivated by mutation or deletion in a majority of human tumors. Theoretically, targeting the p53 pathway would lead to successful anti-cancer treatments. However, no effective p53-based anti-cancer therapy has been developed due to the complexity of the p53 regulators and their poor drugability. Here we demonstrate that focal deletion of TP53 often encompasses neighboring essential genes, rendering cancer cells with hemizygous p53 deletion highly vulnerable to further suppression of such genes. One such gene, POLR2A, encodes the largest subunit of RNA polymerase II complex. We found that its expression correlates with copy number changes and suppression of POLR2A with its inhibitors, alpha-amanitin or short-hairpin RNA, selectively inhibits growth, survival and tumorigenic potential in colon cancer cells with hemizygous TP53 loss, suggesting an novel and effective strategy for cancers with such genomic alternations.

Note: This abstract was not presented at the meeting.

Citation Format: Yunhua Liu, Xiongbin Lu. TP53 loss creates therapeutic vulnerability in 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 2633. doi:10.1158/1538-7445.AM2014-2633
Abstract 2646: Building a powerful ADCs discovery and development platform with novel dolastatin/auristatin payloads
Authors: Hu Shanghui , Zhao Lucy X. , Liu Xu , Li Chao , Hu Wei , Wang Zunrong , Tian Xufang
Published: May 2015

A family of novel warheads derived from dolastatins or auristatins were designed and synthesized. They showed similar or better antitumor activities against several typical cancer cell lines compared with dolastatin 10 or monomethylauristatin E or F. The conjugated ADCs with Trastuzumab have showed potent activities against Her2 breast cancer cell lines. The validated platform with novel cytotoxins can be potentially used to ADCs discovery and development.

Citation Format: Shanghui Hu, Lucy X. Zhao, Xu Liu, Chao Li, Wei Hu, Zunrong Wang, Xufang Tian. Building a powerful ADCs discovery and development platform with novel dolastatin/auristatin payloads. [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 2646. doi:10.1158/1538-7445.AM2014-2646
Abstract 2649: Development of an antibody-drug conjugate targeting TIM-1 for the treatment of ovarian and renal cell carcinoma
Authors: Thomas Lawrence J. , Vitale Laura , O'Neill Thomas , Dolnick Ree , Wallace Paul K. , Minderman Hans , Gergel Lauren E. , Forsberg Eric M. , Boyer James M. , Storey James R. , Hammond Russell A. , Widger Jennifer , Sundarapandiyan Karuna , Crocker Andrea , Marsh Henry C. , Keler Tibor
Published: May 2015

T cell immunoglobulin and mucin domain 1 (TIM-1) is a type I transmembrane protein that was originally described as kidney injury molecule 1 (KIM-1) due to its elevated expression in kidney and urine after renal injury. Tim-1 expression is also upregulated in several human cancers, most notably in renal cell and ovarian carcinomas, but has very restricted expression in healthy tissues thus representing a promising target for antibody mediated therapy. To this end we have developed a fully human monoclonal IgG1 antibody specific for extracellular domain of TIM-1. This antibody was shown to bind purified recombinant chimeric TIM-1-Fc protein and TIM-1 expressed on a variety of transformed cell lines, including Caki-1 (human renal clear cell carcinoma), IGROV-1 (human ovarian adenocarcinoma) and ACHN (human renal cell adenocarcinoma). Internalization studies using confocal microscopy revealed the antibody was rapidly internalized by cells in vitro, and the internalization was confirmed by quantitative imaging flow cytometry using ImageStream. An antibody-drug conjugate (ADC) was produced with the anti-TIM-1 antibody covalently linked to a potent cytotoxin, monomethyl auristatin E (MMAE), and designated CDX-014. The ADC was shown to exhibit in vitro cytostatic or cytotoxic activity against a variety of TIM-1 expressing cell lines, but not on TIM-1 negative cell lines. Using the Caki-1 and IGROV-1 xenograft models, CDX-014 showed significant anti-tumor activity in the range of 75-300 μg/dose given every four days for a total of four doses. Activities are on-going to support the manufacturing and IND-enabling studies in order to advance CDX-014 towards clinical studies in renal cell carcinomas and potentially other TIM-1 expressing tumors.

Citation Format: Lawrence J. Thomas, Laura Vitale, Thomas O'Neill, Ree Dolnick, Paul K. Wallace, Hans Minderman, Lauren E. Gergel, Eric M. Forsberg, James M. Boyer, James R. Storey, Russell A. Hammond, Jennifer Widger, Karuna Sundarapandiyan, Andrea Crocker, Henry C. Marsh, Tibor Keler. Development of an antibody-drug conjugate targeting TIM-1 for the treatment of ovarian and renal cell carcinoma. [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 2649. doi:10.1158/1538-7445.AM2014-2649
Abstract 266: How many epidemiological types of breast cancer: Two, three, four, or more
Authors: Anderson William F. , Rosenberg Philip S. , Prat Aleix , Perou Charles M. , Sherman Mark E.
Published: May 2015

Background: Breast cancer is a heterogeneous disease, divisible into a variable number of clinical subtypes depending upon the analytical approach. A fundamental question is how many etiological subtypes underlie the spectrum of clinical breast tumors? A clinical subtype represents a grouping according to prognosis (outcome) or prediction (expected treatment response), whereas an etiological subtype reflects a common set of causes.

Methods: We initiated a systematic literature review to examine the historical, epidemiological, biostatistical, and molecular evidence for breast cancer etiology. Information sources included CANCERLIT, Index Medicus, and PubMed. Data resources included the Surveillance, Epidemiology, and End Results program.

Results: A bimodal age distribution at diagnosis was a fundamental characteristic of breast cancer for important tumor characteristics, risk factor profiles, molecular markers, and prognosis; suggestive of a ‘mixture’ of two main etiological subtypes in varying proportions in different populations. The first breast cancer tended to arise early in life with modal age-at-diagnosis near 50 years and generally behaved aggressively. The second breast cancer occurred later in life with modal age near 70 years, and usually portended a more indolent clinical course.

Conclusion: Epidemiological and molecular patterns suggest that breast cancer etiology reflects a bimodal breast cancer mixture model, possibly emerging from two stem cells of origin. Notwithstanding, the potential added value of more detailed categorizations and personalized approaches for the targeted treatment of breast cancer, we suggest that the development of criteria to better identify the two proposed main etiologic types would advance etiologic research and the prevention of breast cancer.

Citation Format: William F. Anderson, Philip S. Rosenberg, Aleix Prat, Charles M. Perou, Mark E. Sherman. How many epidemiological types of breast cancer: Two, three, four, or more. [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 266. doi:10.1158/1538-7445.AM2014-266
Abstract 2666: Monoclonal antibodies specific for the oncofetal antigen - immature laminin receptor: Tumor selectivity, rapid internalization and in vivo efficacy
Authors: McClintock Shannon D. , Dame Michael K. , Aslam Muhammad N. , Ali Saqib , Knibbs Randall N. , Warner Roscoe L. , Varani James
Published: May 2015

A series of murine monoclonal antibodies were generated using recombinant oncofetal antigen - immature laminin receptor protein (OFA/iLRP) as the immunogen. Several of the antibodies detected the 37kD OFA/iLRP but did not recognize the structurally related 67kD mature laminin receptor protein (LRP), as determined by western blot analysis. Additional antibodies demonstrated reactivity with both proteins. Those antibodies specific for the 37kD moiety bound to recombinant OFA/iLRP with high affinity (Kaff = 1-2 x 10-10M; Biacore technology). These antibodies also reacted with native OFA/iLRP on the surface of human tumor cells with high affinity (Kaff = 1-2 x 10-9M) but did not show significant reactivity with normal human epithelial cells or fibroblasts. In contrast, antibodies that interacted with both 37kD OFA/iLRP and 67kD mature LRP were reactive with both tumor cells and normal cells. Antibodies specific to OFA/iLRP were internalized upon binding to the target protein on human tumor cells. Two monoclonal antibodies from this group were tested for anti-tumor activity in a murine model of B-cell leukemia. BALB/c mice were injected with A20 leukemia cells either intramuscularly or intravenously. Mice were given a total of six intraperitoneal 100µg antibody injections over a two-week period following tumor initiation. Both antibodies slowed growth of the intramuscular primary tumor by approximately 45%. More importantly, in the intravenous tumor model, the treatments reduced systemic blood tumor levels by greater than 70% and suppressed liver tumor formation by up to 46%. These high affinity tumor-selective antibodies potentially provide a front-line or adjuvant therapy for hematological malignancies.

Citation Format: Shannon D. McClintock, Michael K. Dame, Muhammad N. Aslam, Saqib Ali, Randall N. Knibbs, Roscoe L. Warner, James Varani. Monoclonal antibodies specific for the oncofetal antigen - immature laminin receptor: Tumor selectivity, rapid internalization and in vivo efficacy. [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 2666. doi:10.1158/1538-7445.AM2014-2666
Abstract 2668: RG7116, a novel humanized anti-HER3 antibody with superior preclinical in vitro and in vivo efficacy in combination with, everolimus and other anti-cancer agents
Authors: Bossenmaier Birgit , Friess Thomas , Weisser Martin , Lechner Stefanie , Abraham Esther , Hoch Monika , Mirschberger Christian
Published: May 2015

HER3 is a member of the Human Epidermal Growth Factor Receptor (HER) family. HER3 is a kinase dead receptor, but by forming heterodimers with other HER family receptors, HER3 works as amplifier for PI3 kinase driven tumorigenesis. It has been reported that tumors treated with EGFR-, HER2-, cMET-or mTOR targeted therapies can escape via HER3 activation or upregulation. HER3 is expressed in a large variety of tumors for example in non-small cell lung cancer (NSCLC), head and neck, colorectal, gastric, pancreatic, breast, ovarian, thyroid and prostate cancer. Anti-HER3 antibodies can work via various mechanisms including: (1) blocking ligand (HRGs) binding to the receptor, (2) blocking heterodimerization with other HER family members (HER1, 2 and 4), (3) downregulation of the receptor from the cell surface, and (4) engaging immune effector functions such as antibody-dependent cellular cytotoxicity (ADCC). The first three mechanisms lead to inhibition of HER3 phosphorylation and downstream signaling thereby resulting in tumor cell growth inhibition, while ADCC is a mechanism of direct target cell killing triggered by cross-linking of Fc receptors on immune effector cells (e.g. NK cells, macrophages).

RG7116 is a novel humanized and glycoengineered IgG1 antibody currently in clinical development, that binds to HER3 with high affinity. This antibody prevents ligand binding and receptor heterodimerization, thereby blocking receptor phosphorylation. In various tumor xenograft models monotherapy treatment with this antibody leads to substantial tumor growth inhibition. Only in a few cases monotherapy treatment resulted in complete tumor remission. Most of the models initially show convincing efficacy, but tumors regrow after a while. Combination therapy with other HER targeted therapies such as pertuzumab, cetuximab or erlotinib, lead to complete remission in preclinical models. The combination of RG7116 with downstream signaling inhibitors like: everolimus (mTOR) andand other anti-cancer agents leads to increased efficacy.

Citation Format: Birgit Bossenmaier, Thomas Friess, Martin Weisser, Stefanie Lechner, Esther Abraham, Monika Hoch, Christian Mirschberger. RG7116, a novel humanized anti-HER3 antibody with superior preclinical in vitro and in vivo efficacy in combination with, everolimus and other anti-cancer agents. [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 2668. doi:10.1158/1538-7445.AM2014-2668
Abstract 2672: Vinyl sulfone analogues of lysophosphatidylcholine irreversibly inhibit autotaxin and prevent angiogenesis in melanoma
Authors: Murph Mandi M. , Altman Molly , Jia Wei , Nguyen Duy , Fambrough Jada , Hardman William J. , Jiang Guowei , Madan Damian , Zhang Jianxing , Prestwich Glenn D.
Published: May 2015

Autotaxin (ATX) is an enzyme discovered in the conditioned medium of cultured melanoma cells and identified as a protein that strongly stimulates motility. This unique ectonucleotide pyrophosphatase and phosphodiesterase facilitates the removal of a choline headgroup from lysophosphatidylcholine (LPC) to yield lysophosphatidic acid (LPA), which is a potent lipid stimulator of tumorigenesis. Thus, ATX has received renewed attention because it has a prominent role in malignant progression and represents a promising area of research with significant translational potential. Since ATX inhibitors may have broad implications for therapy, we sought to create a novel series of inhibitors for use against cancer, especially melanoma. Herein we report on the synthesis and biological activity of a targeted affinity label for the active site of ATX, which has a critical threonine residue that acts as a nucleophile in the lysophospholipase D reaction to liberate choline. We synthesized a set of vinyl sulfone analogs of ATX that function as irreversible inhibitors of ATX and inactivate the enzyme. We commenced biological testing of this compound with viability assays against multiple cancer cell lines whereby the IC50 values ranged from 6.74 - 0.39 μM, which was consistent with the Ki of the vinyl sulfone (3.50 μM). In addition, this compound was also able to significantly inhibit melanoma cell wound closure and pore migration. Most importantly, the vinyl sulfone significantly inhibited melanoma progression using an in vivo tumor model by preventing angiogenesis. Taken together, this suggests that the vinyl sulfone is a potent and irreversible ATX inhibitor with significant biological activity both in vitro and in vivo.

Note: This abstract was not presented at the meeting.

Citation Format: Mandi M. Murph, Molly Altman, Wei Jia, Duy Nguyen, Jada Fambrough, William J. Hardman, Guowei Jiang, Damian Madan, Jianxing Zhang, Glenn D. Prestwich. Vinyl sulfone analogues of lysophosphatidylcholine irreversibly inhibit autotaxin and prevent angiogenesis in 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 2672. doi:10.1158/1538-7445.AM2014-2672
Abstract 2673: A novel ligand-independent peptide inhibitor of TREM-1 attenuates inflammation and suppresses tumor growth in mice
Authors: Sigalov Alexander B.
Published: May 2015

Non-small cell lung cancer (NSCLC) comprises about 85% of all lung cancers, accounting for over 1.5 million new cases annually. Despite advances in therapy, the 5-year survival rate is as low as 15%. The limitations in efficacy and safety associated with available treatments for NSCLC highlight the need for new treatments. As found recently, triggering receptor expressed on myeloid cells (TREM-1) plays a role in NSCLC progression. Inhibition of TREM-1 by short hairpin RNA (shRNA) in macrophages suppresses cancer cell invasion in vitro. In clinical setting, high level of TREM-1 expression in tumor-associated macrophages is associated with cancer recurrence and poor survival of patients with NSCLC. However, the precise function of TREM-1 and the nature of its ligand are not yet known. Here we show that TREM-1 can be specifically silenced in vitro and in vivo using a novel ligand-independent peptide inhibitor, which was designed using a new model of immune signaling, the signaling chain homooligomerization (SCHOOL) model. Blockade of TREM-1 function using non-toxic and non-immunogenic SCHOOL peptide inhibitors: 1) delays tumor growth in xenograft models of human NSCLC and 2) substantially decreases cytokine production in vitro and in vivo. In addition, macrophage-targeted delivery of SCHOOL peptides utilizing lipoprotein-mimicking nanoparticles significantly increased peptide half-life and dosage efficacy. Together, the results suggest that ligand-independent modulation of TREM-1 function using small synthetic peptides might be a suitable treatment for NSCLC and possibly other types of inflammation-associated cancers.

Citation Format: Alexander B. Sigalov. A novel ligand-independent peptide inhibitor of TREM-1 attenuates inflammation and suppresses tumor growth in mice. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 2673. doi:10.1158/1538-7445.AM2014-2673
Abstract 2676: Inhibition of bmp signaling suppresses metastasis in mammary cancer
Authors: Owens Philip , Pickup Michael W. , Novitskiy Sergey V. , Giltnane Jennifer M. , Gorska Agnes E. , Hopkins Corey R. , Hong Charles C. , Moses Harold L.
Published: May 2015

Bone Morphogenetic Proteins (BMPs) are secreted cytokines/growth factors that play differing roles in cancer. BMPs are overexpressed in human breast cancers, but loss of BMP signaling in mammary carcinomas can accelerate metastasis. We show that human breast cancers display active BMP signaling, which is rarely downregulated or homozygously deleted. We hypothesized that systemic inhibition of BMP signaling in both the tumor and the surrounding microenvironment could prevent tumor progression and metastasis. To test this hypothesis, we used DMH1, a BMP antagonist in MMTV.PyVmT expressing mice. Treatment with DMH1 reduced lung metastasis and the tumors were less proliferative and more apoptotic. In the surrounding tumor microenvironment, treatment with DMH1 altered fibroblasts, lymphatic vessels and macrophages to be less tumor promoting. These results indicate that inhibition of BMP signaling may successfully target both the tumor and the surrounding microenvironment to reduce tumor burden and metastasis.

Citation Format: Philip Owens, Michael W. Pickup, Sergey V. Novitskiy, Jennifer M. Giltnane, Agnes E. Gorska, Corey R. Hopkins, Charles C. Hong, Harold L. Moses. Inhibition of bmp signaling suppresses metastasis in mammary 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 2676. doi:10.1158/1538-7445.AM2014-2676
Abstract 2681: 4-methylumbelliferone: Dietary supplement turned chemo-preventive and anti-metastatic agent for prostate cancer
Authors: Yates Travis , Alonzo David , Lokeshwar Soum , Hoye Kelly , Lopez Luis E. , Hupe Marie , Lokeshwar Vinata
Published: May 2015

INTRODUCTION: Hyaluronic acid (HA), a glycosaminoglycan, is associated with prostate cancer (PCa) progression and metastasis. 4-methylumbelliferone (4-MU) is dietary supplement that inhibits HA-synthesis. In this study we evaluated chemopreventive and therapeutic efficacy of 4-MU to prevent PCa growth and metastasis in three PCa models.

METHODS: Efficacy of daily oral gavage of 4-MU was evaluated in 3 PCa models: Model 1: TRAMP mice (n = 8-20/group) were treated with vehicle or 4-MU (450 mg/kg) by starting stage-specific treatment at 8 (PIN stage), 12 (adenocarcinoma) and 22 (invasive carcinoma) wks of age. Model 2: Mice were treated with 4-MU (200 mg/kg or 450 mg/kg) following intracardiac injection of Luciferase expressing PC3-ML cells. 3. Palpable DU145 xenografts were treated with 4-MU (200 and 450 mg/kg). Effect of 4-MU on EMT markers, HA receptors was evaluated by Q-PCR, immunoblotting and/or immunohistochemistry in PCa cells and xenograft tissues. HA add back and overexpression studies were conducted to evaluate the mechanism of action of 4-MU.

RESULTS: In the TRAMP model, at 28 wks, 100% of vehicle treated mice developed PCa, but tumor growth and progression was inhibited in all 4-MU treated groups; P+SV weight (g): vehicle: 3.2±2.9; 8 wk: 0.43±0.14; 12 wk: 0.35±0.04; 22 wk: 1.0±0.35 g. The P+SV weight in TRAMP mice at 22 wks of age was 0.9±0.04, showing that late stage administration of 4-MU halted further tumor progression. Animals in 8, 12 and 22 wk groups remained tumor free until 52, 44 and 34 wks respectively, even after stopping treatment at 28 wks. While 55% of vehicle treated animals developed metastasis, none of the treated groups had metastasis. In the PC3-ML intracardiac model, 100% of the mice in the vehicle group but none in the treatment group developed skeletal metastasis. In the DU145 model, 4-MU inhibited tumor growth. No serum/organ toxicity or weight loss was observed in any treatment groups. In all models, 4-MU treatment downregulated HA, HA receptors (CD44, RHAMM) and EMT markers (β-catenin, Zeb2) by >2-fold) but up-regulated E-cadherin. HA addition and overexpression of myristoylated AKt inhibited 4-MU effects.

CONCLUSION: 4-MU is a potent non-toxic, oral chemopreventive agent, which inhibits PCa growth and metastasis by abrogating HA-signaling and reversing EMT.

Support: R01 CA 123063-04 (VBL); R01 CA 72821-11 (VBL)

Note: This abstract was not presented at the meeting.

Citation Format: Travis Yates, David Alonzo, Soum Lokeshwar, Kelly Hoye, Luis E. Lopez, Marie Hupe, Vinata Lokeshwar. 4-methylumbelliferone: Dietary supplement turned chemo-preventive and anti-metastatic agent for prostate 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 2681. doi:10.1158/1538-7445.AM2014-2681
Abstract 2684: Inhibition of tumor growth and angiogenesis by SP-2, an anti-LGALS3BP antibody
Authors: Piccolo Enza , Trani Sara , Tinari Nicola , Rossi Cosmo , Sorda Rossana L. , Lattanzio Rossano , D'Egidio Maurizia , Risio Annalisa D. , Grassadonia Antonino , Spinella Francesca , Bagnato Anna , Piantelli Mauro , Natoli Clara , Iacobelli Stefano
Published: May 2015

Background: Accumulating evidence indicates that serum and tissue levels of the lectin galactoside-binding soluble 3 binding protein (LGALS3BP), a secreted glycoprotein, are elevated in human cancer. Recently, we have identified LGALS3BP as a factor capable of stimulating angiogenesis of microvascular endothelial cells in culture as well as in vivo. However, the potential therapeutic implications of LGALS3BP function blockade, has not been explored yet.

Methods: Here we tested the ability of an anti-LGALS3BP monoclonal antibody, named SP-2, to antagonize LGALS3BP-induced angiogenesis and tumor growth.

Results: SP-2 dose-dependently inhibited HUVEC tubulogenesis induced by either conditioned medium of breast cancer and melanoma cells or purified recombinant LGALS3BP. This was accompanied by inhibition of FAK, Akt and ERKs phosphorylation as well as FAK recruitment to membrane sites and actin remodeling. In vivo, SP-2 inhibited LGALS3BP-stimulated angiogenesis and restrained growth of different xenograft models of human cancer. Finally, the combination of SP-2 with low-dose Bevacizumab was more effective than either agent alone in suppressing angiogenesis and tumor growth.

Conclusions: Targeting LGALS3BP with SP-2 could represent a promising therapeutic approach for LGALS3BP expressing tumors.

Citation Format: Enza Piccolo, Sara Trani, Nicola Tinari, Cosmo Rossi, Rossana La Sorda, Rossano Lattanzio, Maurizia D'Egidio, Annalisa Di Risio, Antonino Grassadonia, Francesca Spinella, Anna Bagnato, Mauro Piantelli, Clara Natoli, Stefano Iacobelli. Inhibition of tumor growth and angiogenesis by SP-2, an anti-LGALS3BP antibody. [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 2684. doi:10.1158/1538-7445.AM2014-2684