bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 1933: Novel roles of receptor tyrosine kinase AXL in the control of stem cell pluripotency and reprogramming
Authors: Cho Yee Sook , Son Mi-Young , Seol Binna
Published: May 2015

The extensive molecular characterization of human pluripotent stem cells (hPSCs), human embryonic stem cells (hESCs), and human induced pluripotent stem cells (hiPSCs) is required Binnbefore they can be applied in the future for personalized medicine and drug discovery. Despite the efforts that have been made with kinome analyses, we still lack in-depth insights into the molecular signatures of receptor tyrosine kinases (RTKs) that are related to pluripotency. Here, we present the first detailed and distinct repertoire of RTKs characteristic for hPSC pluripotency by determining both the expression and phosphorylation profiles of RTKs in hESCs and hiPSCs using RT-PCR with degenerate primers that target conserved tyrosine kinase domains and phospho-RTK array, respectively. Among the RTKs tested, the up-regulation of EPHA1, ERBB2, FGFR4, and VEGFR2 and the down-regulation of AXL, EPHA4, PDGFRB, and TYRO3 in terms of both their expression and phosphorylation levels were predominantly related to the maintenance of hPSC pluripotency. Notably, the specific inhibition of AXL was significantly advantageous in maintaining undifferentiated hESCs and hiPSCs and for the overall efficiency and kinetics of hiPSC generation. Additionally, a global phosphoproteomic analysis showed that approximately 30% of the proteins (293 of 970 phosphoproteins) showed differential phosphorylation upon AXL inhibition in undifferentiated hPSCs, revealing the potential contribution of AXL-mediated phosphorylation dynamics to pluripotency-related signaling networks. Our findings provide a novel molecular signature of AXL in pluripotency control that will complement existing pluripotency-kinome networks.

Citation Format: Yee Sook Cho, Mi-Young Son, Binna Seol. Novel roles of receptor tyrosine kinase AXL in the control of stem cell pluripotency and reprogramming. [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 1933. doi:10.1158/1538-7445.AM2014-1933
Abstract 1947: Plasticity of CD44+ colorectal cancer stem cells depends on TGF-beta-induced epithelial mesenchymal transition(EMT): Evidences from an ex vivo culture
Authors: Nakano Michitaka , Ariyama Hiroshi , Tamura Shingo , Isobe Taichi , Miyawaki Kohta , Okumura Yuta , Kusaba Hitoshi , Baba Eishi , Akashi Koichi
Published: May 2015

Background

EpCAMhigh CD44+ colorectal cancer (CRC) cells are thought to be cancer stem cells. Recently CD44- CRC cells are also suggested to gain a character of cancer stem cells, but the molecular mechanisms have not been clarified. Epithelial-mesenchymal transition (EMT), which is observed in several caner cell lines, could be a possible process of cancer cells to obtain stemness. However, whether primary human CRC cells underwent EMT has not been proven.

Patients and Methods

We obtained surgical specimens of 30 cases of advanced CRC, and cultured isolated primary cancer cells in matrigel-based medium containing several growth factors. For induction of EMT, TGF-beta was added into the culture of CD44+ and CD44- cells. Immunocytochemistry staining and flow cytometry of the spheroid cells and single cell PCR analysis of the cultured cells using 48-gene set that included EMT-related genes (BioMark HD System:Fluidigm Corporation) were performed.

Results

Cancer cells grew spherically (50 μm> diameter) in 20 out of 30 samples after a week culture of whole isolated cancer cells. The sphere mostly consisted of CD44+ cells, and non-sphere forming single cells were CD44-negative. Isolated CD44+ cells from primary samples gave rise to CD44+ and CD44- cells in a week culture. Interestingly, 10% of CD44- cell from primary samples also expressed CD44. Similar to the previous findings of cell lines that TGF-beta-induced EMT could convert CD44- cells into CD44+ cancer initiating cells, increased number of CD44+ cells appeared from primary CD44- cells cultured with TGF-beta. In this culture, N-cadherin+ cells increased time-dependent manner and most of this N-cadherin expressing cells co-expressed CD44. In single cell PCR analysis, increased expression of EMT-related genes, vimentin and TWIST1, were preferentially detected in CD44+N-Cadherin+ cells.

Conclusions

To our knowledge, this is the first report that CD44- cells from primary samples undergo EMT and convert into CD44+ cells by TGF-β treatment. Investigation whether these CD44+ converted cells have cancer stem cell properties such as tumorigenic potential in immunodeficient mouse, self renewing ability and drug resistance is underway.

Citation Format: Michitaka Nakano, Hiroshi Ariyama, Shingo Tamura, Taichi Isobe, Kohta Miyawaki, Yuta Okumura, Hitoshi Kusaba, Eishi Baba, Koichi Akashi. Plasticity of CD44+ colorectal cancer stem cells depends on TGF-beta-induced epithelial mesenchymal transition(EMT): Evidences from an ex vivo culture. [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 1947. doi:10.1158/1538-7445.AM2014-1947
Abstract 1962: Macrophages mediate gemcitabine resistance of pancreatic adenocarcinoma by up-regulating cytidine deaminase
Authors: Amit Moran , Weizman1 Noam , Binenbaum Yoav , Shabtay-Orbach Ayelet , Wong Richard J. , Gil Ziv
Published: May 2015

Resistance to pharmacologic agents used in chemotherapy is common in most human carcinomas, including pancreatic ductal adenocarcinoma (PDA), which is resistant to almost all drugs, including gemcitabine, a nucleoside analog used as first-line treatment. Poor survival rates of PDA patients have, therefore, not changed much over 4 decades. Recent data indicated that tumor-associated macrophages (TAMs), which are abundant in the microenvironment of several tumors, including PDA, secrete pro-tumorigenic factors which contribute to cancer progression and dissemination. In this study, we show for the first time that TAMs can also induce chemoresistance of PDA by reducing gemcitabine-induced apoptosis. Macrophages co-cultured with cancer cells or TAMs conditioned medium significantly reduced apoptosis and activation of the caspase-3 pathway during gemcitabine treatment. In vivo PDA models of mice, which have reduced macrophage recruitment and activation, demonstrated improved response to gemcitabine compared to controls. Similarly, inhibition of monocytes/macrophages trafficking by a CSF1-receptor antagonist GW2580 augmented the effect of gemcitabine in a transgenic mouse PDA model that was resistant to gemcitabine alone. Analysis of multiple proteins involved in gemcitabine delivery and metabolism revealed that TAMs induced upregulation of cytidine deaminase (CDA), the enzyme that metabolizes the drug following its transport into the cell. Decreasing CDA expression by PDA cells blocked the protective effect of TAMs against gemcitabine. These results provide the first evidence of a paracrine effect of TAMs, which mediates acquired resistance of cancer cells to chemotherapy. Modulation of macrophage trafficking or inhibition of CDA may offer a new strategy for augmenting the response of PDA to chemotherapy.

Citation Format: Moran Amit, Noam Weizman1, Yoav Binenbaum, Ayelet Shabtay-Orbach, Richard J. Wong, Ziv Gil. Macrophages mediate gemcitabine resistance of pancreatic adenocarcinoma by up-regulating cytidine deaminase. [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 1962. doi:10.1158/1538-7445.AM2014-1962
Abstract 1972: The sodium channel auxiliary subunit SCN1B promotes breast tumor growth and metastasis
Authors: Nelson Michaela , Millican-Slater Rebecca , Forrest Lorna C. , Brackenbury William J.
Published: May 2015

Voltage-gated Na+ channels (VGSCs) are heteromeric proteins composed of pore-forming α subunits and smaller β subunits. The β subunits are multifunctional channel modulators and are members of the immunoglobulin superfamily of cell adhesion molecules (CAMs). β1, encoded by SCN1B, is best characterized in the central nervous system (CNS), where it plays a critical role in regulating electrical excitability, neurite outgrowth and migration during development. β1 is also expressed in breast cancer cell lines, where it regulates adhesion and migration in vitro. Using the Oncomine database, we found that SCN1B mRNA was up-regulated in breast cancer, compared with normal breast. Similarly, β1 protein was up-regulated in a cohort of breast cancer tissue specimens compared with surrounding normal tissue. Over-expression of β1 in MDA-MB-231 cells substantially increased tumor growth and metastasis from orthotopic xenografts in immune-deficient mice. β1 had no effect on the density of Ki67-positive cycling cells in the primary tumors. However, β1 increased the density of CD31-positive vessel structures and reduced the density of apoptotic cells expressing activated caspase-3. β1-expressing MDA-MB-231 cells had an elongate morphology in tumors in vivo and in 2D culture in vitro. β1 potentiated the outgrowth of processes from MDA-MB-231 cells and MCF-7 cells co-cultured with fibroblasts, via trans-homophilic adhesion. Both the src family tyrosine kinase inhibitor PP2 and siRNA targeting fyn kinase blocked β1-mediated process extension in breast cancer cells. Thus, β1-mediated process outgrowth in breast cancer cells requires the presence and activity of fyn kinase. This recapitulates the mechanism by which β1 regulates neurite outgrowth in CNS neurons. We conclude that when present in breast tumors, β1 drives pathological growth and cellular dissemination by recapitulating its well-defined role in CNS ontogeny. This study is the first demonstration of a functional role for β1 as a CAM in tumor growth and metastasis. We propose that targeting β1-mediated adhesion interactions may have potential as a novel anti-cancer therapy.

Citation Format: Michaela Nelson, Rebecca Millican-Slater, Lorna C. Forrest, William J. Brackenbury. The sodium channel auxiliary subunit SCN1B promotes breast tumor growth and metastasis. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1972. doi:10.1158/1538-7445.AM2014-1972
Abstract 2045: Identifying key molecular events at the onset of melanoma using a neural crest stem cell marker
Authors: Kaufman Charles K. , Mosimann Christian , White Richard M. , Matos Dominic , Zon Leonard I.
Published: May 2015

An ongoing challenge in cancer biology is understanding the earliest, initiating events that switch a premalignant cell into a fully competent cancer cell. Driven by this challenge, we focused on the zebrafish gene crestin that marks the embryonic neural crest from the onset of somitogenesis through 72 hours post fertilization when it normally turns off. Surprisingly, our lab previously showed that crestin mRNA is reexpressed in melanoma tumors in adult zebrafish, reading out a neural crest progenitor state. We have developed a fluorescent reporter using the crestin promoter/enhancer that recapitulates the embryonic expression pattern of crestin, and when bred into our BRAFV600E/p53 mutant melanoma zebrafish model, marks grossly visible melanoma tumors. Remarkably, we found that crestin:EGFP becomes active when lesions are only a few cells in number, potentially in the first cell of the melanoma. Using a crestin:CreERt2 inducible recombinase together with a lox-dependent fluorescent lineage tracer line ubi:switch, multiple neural crest descendant lineages including melanocytes can be traced. Further by expressing the melanocyte lineage master transcription factor mitf under the control of the crestin promoter, we can rescue melanocyte formation in mitf null embryos, and in the Na/BRAFV600E/p53 melanoma-prone mutant background, some adult fish develop darkly pigmented patches and melanoma tumors. Finally, we isolated small patches of crestin:EGFP positive cells and show that these precursor lesions are enriched for expression of the neural crest progenitor transcription factor sox10. These data support a model in which BRAFV600E/p53 mutated melanocytes stochastically reactivate an early melanocyte or neural crest progenitor program as read out by crestin reactivation at the initiation of melanoma formation. Using our novel reporter, we are able to analyze in vivo the earliest steps of cancer formation as well as the neural crest lineage program.

Citation Format: Charles K. Kaufman, Christian Mosimann, Richard M. White, Dominic Matos, Leonard I. Zon. Identifying key molecular events at the onset of melanoma using a neural crest stem cell marker. [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 2045. doi:10.1158/1538-7445.AM2014-2045
Abstract 2476: A novel NUT translocation partner binds to BRD4 and is necessary for the blockade of differentiation in NUT midline carcinoma
Authors: Walsh Erica , Kuhnle Simone , Rahman Shaila , Lemieux Madeleine , Howley Peter , French Christopher
Published: May 2015

NUT midline carcinoma (NMC) is an aggressive type of squamous cell carcinoma that typically harbors BRD4/3-NUT fusion oncogenes which encode chimeric proteins that block differentiation and maintain tumor growth. However, in 30% of cases NUT is fused to yet to be identified non-BRD gene(s). Using RNA sequencing, we identified a novel gene fused to NUT in a NMC cell line (1221), fusing a novel 5′ coding sequence to the NUT gene. Like Brd4/3, this gene encodes a protein that is also involved in epigenetic regulation, and we find that siRNA knockdown of this protein leads to differentiation of the 1221 cells as well as of three BRD4-NUT-positive NMC cell lines. We have established that the novel NUT fusion protein encoded by this translocated gene binds to BRD4. We have mapped the regions of Brd4 and of the novel fusion protein involved in complex formation and are exploring whether association of the novel protein with Brd4 is required for the blockade of differentiation in NMC. Differentiation of TC-797 cells induced by knockdown of BRD4-NUT is abrogated by enforced expression of the novel NUT-fusion gene. Together, these findings identify a novel BRD4-NUT-interacting protein whose expression is required for the maintenance of the undifferentiated state in NMC, and when fused to NUT, is oncogenic and can recapitulate the function of BRD4-NUT to block differentiation.

Citation Format: Erica Walsh, Simone Kuhnle, Shaila Rahman, Madeleine Lemieux, Peter Howley, Christopher French. A novel NUT translocation partner binds to BRD4 and is necessary for the blockade of differentiation in NUT midline 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 2476. doi:10.1158/1538-7445.AM2014-2476
Abstract 2481: Complex deregulation of p73 transcripts in breast tissues: overexpression in benign breast fibroadenomas, and down-regulation in breast cancers
Authors: Tourpin Sophie , Alsafadi Samar , Mathieu Marie-Christine , Delaloge Suzette , Andre Fabrice , Ahomadegbe Jean C.
Published: May 2015

p73, a p53-related gene, encodes two classes of isoforms with opposing functions: (1) a full-length transactivation-competent p73 protein (TAp73) with tumor suppressor activity; and (2) a group of NH2-terminally truncated, transactivation-deficient p73 proteins, ΔEx2p73, ΔEx2-3p73, ΔNp73 and ΔN'p73 (collectively named DNp73) which exert oncogenic activity by inactivating p53 and TAp73. In contrast to p53, p73 is essentially never mutated in cancer. Some studies have focused on the analysis of p73 alterations in breast cancer, but the results are often contradictory. However, it should be noted that there is no study on the comparative analysis of the p73 levels in matched normal breast tissues-breast cancer from the same patients, probably because of the difficulty of obtaining such matched tissues. To study whether p73 is associated with breast carcinogenesis, deregulations of TAp73 and DNp73 were assessed in 103 breast tissues including breast cancer (BC) exhibiting no inflammatory symptoms, inflammatory BC (IBC), normal breast epithelium adjacent to BC (N) and benign breast fibroadenomas (FA). IBC is a rare but aggressive form of BC with a very poor prognosis. Tumor characteristics and the risk of death and relapse were examined in each patient. Surprisingly, we found that antiapoptotic ΔNp73 transcripts and protein levels were down-regulated in BC, compared to that found in normal adjacent tissue, suggesting that this isoform could be associated with other processes during breast carcinogenesis such as differentiation. In contrast with this finding, ΔNp73 was unchanged in FA. Δex2p73 levels were upregulated in BC and FA (p=0.06 and 0.04 respectively), but the level was higher in FA. TAp73 and Δex2-3p73 were unchanged in FA and BC. Intriguingly, TAp73 and Δex2-3p73 transcripts were higher in ER-negative BC, compared to ER-positive BC (p=0.07 and 0.04 respectively). Taken together, our results show that, surprisingly, both suppressor and oncogenic isoforms of p73 were more deregulated in FA than in BC. Consequently, the reports demonstrating upregulation of p73 isoforms in BC should be considered with caution.

Note: This abstract was not presented at the meeting.

Citation Format: Sophie Tourpin, Samar Alsafadi, Marie-Christine Mathieu, Suzette Delaloge, Fabrice Andre, Jean C. Ahomadegbe. Complex deregulation of p73 transcripts in breast tissues: overexpression in benign breast fibroadenomas, and down-regulation in 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 2481. doi:10.1158/1538-7445.AM2014-2481
Abstract 2494: A pilot proteomic analysis to identify biomarker proteins in human pancreatic cancer using reverse phase protein array
Authors: Huang Yu-jing , Zhang Nianxiang , Frazier Marsha , Wei Chongjuan
Published: May 2015

Background: Pancreatic cancer is the fourth leading cause of cancer death in the U.S, and with an overall 5-year survival rate less than 4%. The high mortality rate of patients with pancreatic cancer is primarily due to the difficulty of early diagnosis and a lack of effective therapies. There is an urgent need to discover novel molecular targets for early diagnosis and new therapeutic approaches to improve the clinical outcome of this deadly disease. Reverse-phase protein assay (RPPA), a high throughput proteomic approach, provides us a platform to identify differentially expressed proteins and characterize posttranslational protein modifications involved in tumorigenesis.

Methods: In the present study here, we carried out proteomic analysis of pancreatic cancer specimens with matched adjacent, normal-appearing tissue samples from 15 pancreatic cancer patients to evaluate the differentially expressed biomarker proteins. The antibody panel used for RPPA included 132 key proteins involved in various cancer-related pathways. The paired t test was used to determine the significant differences between matched pairs, and the false discovery rate-adjusted p values (q values) were calculated to take into account the effect of multiple comparisons.

Result: Out of the panel of 132 proteins included in RPPA, we found 19 of them had statistically significant differences in expression between matched pairs (q <0.05). Among these 19 proteins, AKT, -catenin, GAB2, and PAI-1 were identified as differentially overexpressed in the pancreatic tumor (a fold change of T/N ≥ 1.5). In addition, overexpression of AKT, -catenin, and GAB2 in pancreatic cancer tissue identified in RPPA has been confirmed by western blot analysis. Further analysis identified several significantly associated canonical pathways and overrepresented network functions using the Ingenuity Pathway Analysis (IPA) tool.

Conclusion: In conclusion, among the three proteins identified in RPPA and validated by western blot, overexpression of GAB2 has not been reported previously in pancreatic cancer. Considering the essential role of GAB2 in two major signaling pathways in cancer (the PI3-AKT and the ERK signaling pathways), identification of GAB2 in pancreatic cancer may provide additional insight into this cancer's pathogenesis.

Citation Format: Yu-jing Huang, Nianxiang Zhang, Marsha Frazier, Chongjuan Wei. A pilot proteomic analysis to identify biomarker proteins in human pancreatic cancer using reverse phase protein array. [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 2494. doi:10.1158/1538-7445.AM2014-2494
Abstract 2522: Development of GADD45β (growth arrest DNA damage-inducible gene 45 beta) agonists for the treatment of hepatocellular carcinoma (HCC)
Authors: Hsu Chiun , Ou Da-Liang , Chen Kuen-Feng , Lin Zhong-Zhe , Cheng Ann-Lii , Shiau Chung-Wai
Published: May 2015

Induction of GADD45β expression, which is associated with cellular stress response and apoptosis regulation, in HCC cells was found to correlate with sensitivity of sorafenib, the standard molecular targeted therapy for advanced HCC. In this study, we use this GADD45β induction as a screening platform to identify novel agents for HCC treatment from sorafenib derivatives that lack RAF kinase inhibition activity. GADD45β expression in Huh-7 cells was measured by quantitative RT-PCR. Cell viability was examined by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Apoptosis was examined by flow cytometry. Signal transduction pathways in cells were assessed by western blotting. In vivo anti-tumor efficacy was tested in mouse xenograft models using Huh7 and Huh7R cells, the latter had acquired resistance to sorafenib. Pharmacokinetic studies were done in Sprague-Dawley rat model. The compound SC-20, which had a N-(4-(quinolin-4-yloxy)phenyl)benzamide scaffold, showed greater GADD45β induction than other derivatives. The nitro group on the quinolone ring of SC-20 was considered important in GADD45β induction. SC-20 induced more prominent apoptosis and inhibition of proliferation in Huh7 cells than sorafenib, independent of MEK/ERK signaling activity in Huh7 cells. SC-20 showed more prominent GADD45β induction and better antitumor activity than sorafenib in both Huh-7 and Huh7R xenograft models and good safety. Pharmacokinetic studies indicated that SC-20 had long plasma half-life (22.5 ± 0.51 hours), low water solubility, high (> 99%) plasma protein binding, and inhibited CYP2C9 and 2C19. GADD45β agonists warrant further development for HCC treatment. (supported by NSC 101-2325-B-002 -039, NSC 101-2321-B-002 -014, NSC 102-2325-B-002 -038)

Citation Format: Chiun Hsu, Da-Liang Ou, Kuen-Feng Chen, Zhong-Zhe Lin, Ann-Lii Cheng, Chung-Wai Shiau. Development of GADD45β (growth arrest DNA damage-inducible gene 45 beta) agonists for the treatment of hepatocellular carcinoma (HCC). [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 2522. doi:10.1158/1538-7445.AM2014-2522
Abstract 2524: Promising early-stage novel androgen receptor antagonists in head-head comparisons with Enzalutamide and Bicalutamide
Authors: Shaw Arthur Y. , Gokhale Vijay , Hulme Christopher , Stratton Steven P.
Published: May 2015

Prostate cancer is the most common male cancer and the second leading cause of cancer-related deaths in developed countries. The androgen receptor (AR) is a key molecular target in the etiology and progression of the disease where the early stages of prostate cancer tumor growth are androgen dependent and respond well to androgen ablation and androgen receptor antagonists. However, castration-resistant prostate cancer (CRPC) typically develops in 1-2 years after androgen deprivation therapy and AR antagonist administration. Despite promising results from the recently approved second-generation AR antagonist Enzalutamide (MDV3100), CRPC remains a largely unmet medical need with less than a 15% 5-year survival rate.

This poster introduces the discovery of a novel series of significantly structurally distinct small-molecule androgen antagonists from current therapeutics with promising biological profiles in (1) an FP binding assay, (2) a GeneBlazerTM functional assay and (3) a study of anti-proliferative activity against LNCaP cell growth. One of several promising compounds from a current collection of ∼100 analogs is exemplified by AR002.

CompoundFP AR binding assay (IC50)GeneBlazerTM β-lactamase reporter assay (IC50)LNCAP cell growth inhibition (GI50)AR002328.7 nM557 nM2.3 μMEnzalutamide920 nM1150 nM11.65 μMBicalutamide145 nM1370 nM30.68 μM

In summary, a novel class of AR antagonists has been identified, encouragingly demonstrating potent activity against AR and inhibition of cell growth in the prostate specific line LNCaP.

Citation Format: Arthur Y. Shaw, Vijay Gokhale, Christopher Hulme, Steven P. Stratton. Promising early-stage novel androgen receptor antagonists in head-head comparisons with Enzalutamide and Bicalutamide. [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 2524. doi:10.1158/1538-7445.AM2014-2524
Abstract 2527: Aspirin and aspirin analogs on esophageal cancer
Authors: Kilari Rajagopal Sharada , Perry Christopher J. , Devitt Andrew , Safrany Stephen T. , Nicholl Iain D.
Published: May 2015

Background

Esophageal cancer is the eighth most common cancer seen worldwide and is the sixth most common cause of death from cancer. The UK alone has over 8,000 new cases of esophageal cancer every year. Epidemiological studies have shown that low-dose daily intake of aspirin can decrease the incidence of esophageal cancer. However, its use as an anti-cancer drug has been restrained because of its side effects exerted through inhibition of cyclooxygenase (COX) enzymes. In our study, we have investigated the effects of a number of novel aspirin analogs on esophageal cancer cell lines.

Methods

The effects of aspirin and its analogs on the viability of esophageal cancer cell lines were tested using the MTT assay. ApoSense and flow cytometric analysis were performed to examine whether aspirin analog-mediated tumor cell death is due to apoptosis or necrosis. Colorimetric assays measuring peroxidase component of cyclooxygenases were employed to screen aspirin analogs for COX inhibition.

Results

Our data suggests that the anti-proliferative property of certain aspirin analogs is greater than that of aspirin itself. Benzoylsalicylates and fumaroyl diaspirin were more effective than aspirin against the oe21 squamous cell carcinoma cells and oe33 esophageal adenocarcinoma cells. Flo-1 esophageal adenocarcinoma cells showed resistance to aspirin and most of the aspirin analogs other than the benzoylsalicylates. Both diaspirin and benzoylsalicylates inhibited metabolic activity in all these esophageal cells. However, apoptosis was induced in only a small proportion. We have also shown that these aspirin analogs do not appear to inhibit COX enzymes.

Conclusion

We have synthesized and characterized a number of novel aspirin analogs that are more effective against esophageal cancer cell lines than aspirin. These compounds do not exert their anti-proliferative effect through induction of apoptosis. Moreover, these analogs inability to inhibit COX enzymes suggests that they may cause fewer or no side effects compared to aspirin.

Citation Format: Rajagopal Sharada Kilari, Christopher J. Perry, Andrew Devitt, Stephen T. Safrany, Iain D. Nicholl. Aspirin and aspirin analogs on esophageal 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 2527. doi:10.1158/1538-7445.AM2014-2527
Abstract 2529: Optimization of small molecules targeting BMI1 protein expression. Part 1. Amino-thiazoles: the first-in-class highly potent inhibitors of BMI1 protein
Authors: Sydorenko Nadiya , Baiazitov Ramil , Choi Soongyu , Lee Chang-Sun , Cao Liangxian , Davis Thomas W. , Almstead Neil G. , Moon Young-Choon
Published: May 2015

BMI1 (B-cell specific Moloney Murine Leukemia Virus Insertion 1) is a gene predominantly expressed in stem cells. A deficiency of BMI1 protein leads to a reduction in the adult stem cell population. Decreasing of BMI1 protein levels by siRNA causes apoptosis and/or senescence in tumor cells in vitro and increases susceptibility to cytotoxic agents. In tumors, the level of BMI1 protein is often elevated. Consequently, the expression level of BMI1 is highly prognostic in many types of cancers. Since BMI1 is non-enzymatic, targeting this protein by traditional drug discovery approaches has not met with success. PTC Therapeutics has developed a novel screening technology referred to as GEMSTM (Gene Expression Modulation by Small molecules) to identify small molecules that modulate the levels of a protein of interest by targeting post-transcriptional regulatory processes. Using this screening technology, we have identified a number of compounds that can selectively reduce levels of BMI1 protein. Schematically, the lead scaffold could be represented by four key components: a bicyclic right core, a heterocyclic middle ring (thiazole), a linking group and a left aryl region. Structure-activity relationships associated with this series have been investigated through medicinal chemistry efforts. Incorporation of a small electron-donating para- substituent at the left part of the molecule is highly effective in decreasing levels of BMI1, indicating the strong influence of both steric and electronic effects on activity. An amino (linking group) moiety was found to be essential for activity. Variation at the right-hand moiety appears to be more tolerated, allowing improvements in both pharmacokinetic and activity profiles. These SAR findings have revealed important pharmacophoric and structural features required for the desired biological activity with this series, and provide a foundation for further lead optimization efforts.

Citation Format: Nadiya Sydorenko, Ramil Baiazitov, Soongyu Choi, Chang-Sun Lee, Liangxian Cao, Thomas W. Davis, Neil G. Almstead, Young-Choon Moon. Optimization of small molecules targeting BMI1 protein expression. Part 1. Amino-thiazoles: the first-in-class highly potent inhibitors of BMI1 protein. [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 2529. doi:10.1158/1538-7445.AM2014-2529
Abstract 2545: Histamine dihydrochloride and interleukin-2 for relapse prevention in AML: Initial results of the Re:MISSION phase IV trial
Authors: Martner Anna , Rydström Anna , Riise Rebecca , Aurelius Johan , Brune Mats , Hellstrand Kristoffer , Thorén Fredrik Bergh
Published: May 2015

BACKGROUND AND METHODS. Immunotherapy with histamine dihydrochloride and low-dose interleukin-2 (HDC/IL-2) has been approved within the EU for relapse prevention in the post-consolidation phase of acute myeloid leukemia (AML) (Blood 108:88). We have performed a phase IV trial (Re:MISSION) to assess the immunomodulatory properties of this regimen and to correlate potential biomarkers of immunity with outcome. Eighty-nine patients (age 19-80) with AML in first complete remission received HDC (0.5 mg sc bid) and human recombinant IL-2 (1MIU sc bid) in ten repeated three-week cycles for 18 months or until relapse. Mononuclear cells were analyzed for NK and T cell phenotypes by flow cytometry at onset and during cycles 1 and 3.

INDUCTION OF NK CELLS AND NCR EXPRESSION DURING THERAPY. Treatment with HDC/IL-2 resulted in a 3-fold expansion of both CD56bright (CD56/CD16-) and CD16+ (CD56+/CD16+) NK cells during cycle 1 (CD56+, P= 10-6, n=47; paired samples t-test). During cycle 1, the median expression intensity of the natural cytotoxicity receptors (NCRs) NKp46 and NKp30 on CD16+ NK cells increased by 50% and 30%, respectively (P=6 x10-8 for NKp46; P=2 x10-7 for NKp30, n=56). For CD56bright cells, the results were discordant for the NCRs with pronounced induction of NKp30 (P=4 x10-13) during cycle 1 but no induction of NKp46 (P=0.51, n=56).

ROLE OF NCR EXPRESSION FOR MAINTENANCE OF REMISSION. An interim analysis of immune markers vs. relapse-free survival (RFS) revealed a strong impact of NK cell NKp46 expression. Patients with NKp46 expression above the median after one 21-day cycle of HDC/IL-2 thus showed significantly higher RFS than those with lower expression (CD16+, P=0.003, HR=3.0, CI 1.4-6.4; CD56bright, P=0.002, HR=3.3, CI: 1.5-7.0; logrank test). High NK cell expression of NKp46 after a treatment cycle also identified a population of elderly patients (>60 years old) with favorable outcome (CD16+, P=0.002, HR=4.1, CI: 1.6-10.2; logrank test). We observed a pronounced expansion of CD4+/CD25+/Foxp3+ regulatory T cells during cycles that did not impact on relapse risk. CONCLUSION. These results highlight the role of NK cells and NCR expression for relapse-free survival in AML.

Citation Format: Anna Martner, Anna Rydström, Rebecca Riise, Johan Aurelius, Mats Brune, Kristoffer Hellstrand, Fredrik Bergh Thorén. Histamine dihydrochloride and interleukin-2 for relapse prevention in AML: Initial results of the Re:MISSION phase IV trial. [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 2545. doi:10.1158/1538-7445.AM2014-2545
Abstract 2553: Pritumumab, a natural human IgG antibody defines a tumor-associated biomarker useful in treating brain cancer patients
Authors: Glassy Mark C. , Gupta Rishab
Published: May 2015

Pritumumab is a natural human IgG1 kappa antibody that has been derived from a B-cell isolated from a regional draining lymph node of a patient with cervical carcinoma. Specificity analysis of the antibody with human tissues showed the target antigen, altered tumor-associated vimentin, to be highly restricted to various epithelial cancers and not normal cells and tissues. Daunomycin-pritumumab conjugates were generated that increased the effectiveness of the antibody. In various phase II clinical trials in Japan 249 patients with brain cancer were treated with unconjugated pritumumab. The overall response rate was between 25-30%, a 9-fold increase over standard care, with several survivors beyond 5-years post-treatment. The patients were on a low dose regimen of 1mg given twice a week for a course of 24 weeks for a total dose of 48 mgs per course. Pritumumab appears to be a safe and effective therapy in patients with brain cancer.

Citation Format: Mark C. Glassy, Rishab Gupta. Pritumumab, a natural human IgG antibody defines a tumor-associated biomarker useful in treating brain cancer patients. [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 2553. doi:10.1158/1538-7445.AM2014-2553
Abstract 2556: The predictive role of tumor-associated macrophages in stage IIIA pN2 non-small cell lung cancer after neoadjuvant chemotherapy and surgery
Authors: Feng Po-Hao , Yu Chih-Teng , Wu Chin-Yang , Yen Tzung-Hai , Lee Kang-Yun
Published: May 2015

Introduction: Neoadjuvant chemotherapy improves survival in patients with pN2 stage IIIA non-small cell lung cancer (NSCLC). However, the majority relapse eventually even with mediastinal downstaging. Our study investigated the predictive role of tumor-associate macrophages (TAMs) in these patients.

Methods: Between 2005 and 2008, twenty-two pN2 stage IIIA NSCLC patients underwent cisplatin/docetaxel neoadjuvant chemotherapy and surgery were retrospectively enrolled. Immunohistochemical staining of CD68 was used to identify macrophages in stored tissues.

Results: The objective response rate was 68%, overall median disease-free survival (DFS) was 13.1 months (95% CI 6.1-20.2 months) and median overall survival (OS) 48.0 months (95% CI 24.0-72.1 months). Multiple Cox regression analysis showed mediastinal downstaging to pN0 (HR=0.039, 95% CI 0.004-0.349, p=0.004) and high total macrophage numbers (HR=1.01, 95% CI 1.002-1.017, p=0.012) were independent factors for DFS. In the 16 patients downstaged to pN0, those with low total macrophage numbers had longer DFS (median 33.4 months), compared with those with high numbers (13.4 months, p=0.037).

Conclusions: Low total macrophage numbers were also an independent factor for better DFS in pN2 stage IIIA NSCLC patients receiving neoadjuvant chemotherapy and surgical resection, which association was kept in patients downstaged to pN0. Further prospective study is warranted to confirm the predictive role of TAM in these patients.

Citation Format: Po-Hao Feng, Chih-Teng Yu, Chin-Yang Wu, Tzung-Hai Yen, Kang-Yun Lee. The predictive role of tumor-associated macrophages in stage IIIA pN2 non-small cell lung cancer after neoadjuvant chemotherapy and surgery. [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 2556. doi:10.1158/1538-7445.AM2014-2556
Abstract 2561: Yeast vector-encoding multiple MUC1 agonist epitopes (yeast-MUC1) can induce MUC1-specific T-cell immune responses
Authors: Tsang Kwong Y. , Boyerinas Benjamin , Jochems Caroline , Rodell Tim , King Thomas , Schlom Jeffey
Published: May 2015

The tumor-associated antigen MUC1 is overexpressed on various human hematological and epithelial malignancies. The MUC1 molecule, which has an N-terminal (MUC1-N) and a C-terminal (MUC1-C, which has been shown to act as an oncogene), is an attractive target for cancer immunotherapy. We have identified and reported 10 agonist epitopes (7 in the C-terminus, 2 in the N-terminus VNTR region, and 1 in the non-VNTR region) that enhance production of CD8 cytotoxic T lymphocytes. These epitopes span HLA-A2, HLA-A3, and HLA-A24 MHC class I alleles, thus encompassing the majority of the North American population. Compared to native epitopes, these agonist epitopes more efficiently generate MUC1-specific T cells, induce production of IFN-gamma by MUC1-specific T cells, and lyse human tumor cells expressing MUC1 native epitopes in an MHC-restricted manner. We have previously shown that heat-killed recombinant Saccharomyces cerevisiae yeast genetically modified to express carcinoembryonic antigen can efficiently activate human dendritic cells (DCs) and stimulate CEA-specific CD8+ T cells. Here, we investigated the ability of a Saccharomyces cerevisiae vector containing the MUC1 transgene (yeast-MUC1) and encoding MUC1 with 8 agonist epitopes to activate human DCs, stimulate MUC1-N- and MUC1-C-specific T cells, and generate MUC1-specific T cells. We show here for the first time that human DCs treated with yeast-MUC1 vectors can activate MUC1-N and MUC1-C agonist-specific T-cell lines and can act as antigen-presenting cells to generate MUC1-N- and MUC1-C-specific T cells specific to each agonist epitopes, and that these T cells are capable of lysing MUC1-expressing tumor cells. Together, these findings provide a rationale for further clinical evaluation of yeast-MUC1 constructs encoding MUC1 agonist epitopes in cancer vaccine immunotherapy.

Citation Format: Kwong Y. Tsang, Benjamin Boyerinas, Caroline Jochems, Tim Rodell, Thomas King, Jeffey Schlom. Yeast vector-encoding multiple MUC1 agonist epitopes (yeast-MUC1) can induce MUC1-specific T-cell immune responses. [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 2561. doi:10.1158/1538-7445.AM2014-2561
Abstract 2589: In vitro activities of the cationic antitumoral peptide LTX-315 against human melanoma cells
Authors: Eike Liv-Marie , Yang Nannan , Rekdal Øystein , Sveinbjornsson Baldur
Published: May 2015

The LTX-315 peptide is a lactoferricin-derived short antitumor peptide which was designed to treat solid tumors with intra-tumoral injections through a two-stage mode of action. First, the collapse of the tumor itself, then the released DAMPs from the dying tumor cell, could induce a subsequent immune protection against recurrences and metastastis. In the present study, we investigate the mechanisms behind the killing of A375 melanoma cells by LTX-315. The peptide kills the tumor cells within a few minutes by direct plasma membrane attack, but at lower concentration internalizes- and can be associated with mitochondria, ultimately leading to a lytic cell death. We show that a fluorescence-labeled peptide was internalized and localized in cytoplasmic vacuoles and accumulated around the mitochondria with subsequent rapid lysis of cells as shown by confocal live cell imaging and transmission electron microscopy. Furthermore we detected the secretion of DAMPs into the extracellular compartment minutes after peptide exposure using ELISA assay, ATP luciferase assay and western blot. Taken together, these findings suggest that LTX-315 has the ability to cause immunogenic cell death in cancer cells, and thus might have a potential as an in situ therapeutic vaccination agent

Citation Format: Liv-Marie Eike, Nannan Yang, Øystein Rekdal, Baldur Sveinbjornsson. In vitro activities of the cationic antitumoral peptide LTX-315 against human melanoma 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 2589. doi:10.1158/1538-7445.AM2014-2589
Abstract 2590: Oral combined therapy with probiotics and alloantigen induces B cell dependent long lasting specific tolerance
Authors: Mercadante Ana Carolina T. , Perobelli Suelen , Alves Ana Paula G. , Gonçalves-Silva Triciana , Mello Wallace , Gomes-Santos Ana C , Miyoshi Anderson , Faria Ana Maria C. , Bonomo Adriana
Published: May 2015

Background. Allogeneic hematopietic stem cell transplantation (aHSCT) is widely used for the treatment of hematologic malignancies. Although aHSCT provides a good response against the malignant cells (GVL), it also leads to the development of graft-versus-host disease (GVHD), a severe disease with high mortality and morbidity rates. Therapy for GVHD is commonly based on non-specific immunosupression of the transplanted recipient, resulting in the concomitant inhibition of the GVL effect. Material and Methods. Here we propose an alternative approach to specifically suppress GVHD, while sparing the GVL, based on oral treatment of transplant donors with recipient antigens, associated with the intake of probiotic Lactococcus lactis as tolerogenic adjuvant (combined therapy). Results. We show that treatment of C57Bl/6 donor mice with combined therapy before the transplant protects the recipients F1 (C57Bl/6XBAL/c) mice from clinical and pathological manifestations of disease, resulting in 100% survival rate. Importantly, the animals keep the immunological competence maintaining the GVL response as well as the response to third party antigens. The protection is specific, long lasting and dependent on donor IL-10 sufficient B cells activity which induces regulatory T cells in the host. Conclusion. These data suggest that combined therapy is a promising strategy for prevention of GVHD with preservation of GVL, opening new possibilities to treat human patients subjected transplantation.

Note: This abstract was not presented at the meeting.

Citation Format: Ana Carolina T. Mercadante, Suelen Perobelli, Ana Paula G. Alves, Triciana Gonçalves-Silva, Wallace Mello, Ana C Gomes-Santos, Anderson Miyoshi, Ana Maria C. Faria, Adriana Bonomo. Oral combined therapy with probiotics and alloantigen induces B cell dependent long lasting specific tolerance. [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 2590. doi:10.1158/1538-7445.AM2014-2590
Abstract 260: Integrative genomic analysis identifies epigenetic marks that mediate genetic risk for epithelial ovarian cancer
Authors: Koestler Devin C. , Chalise Prabhakar , Cicek Mine S. , Cunningham Julie M. , Armasu Sebastian , Larson Melissa C. , Chien Jeremy , Block Matthew , Kalli Kimberly R. , Sellers Thomas A. , Goode Ellen L. , Fridley Brooke L.
Published: May 2015

Both genetic and epigenetic factors influence the development and progression of epithelial ovarian cancer (EOC). However, there is an incomplete understanding of the interrelationship between these factors and whether they interact to impact disease risk. Given that the development of ovarian cancer is complex, we aimed to identify DNA methylation marks that are candidates for mediating ovarian cancer genetic risk. We used 214 cases and 214 age-matched controls from the Mayo Clinic Ovarian Cancer Study. Pretreatment, blood-derived DNA was profiled for genome-wide methylation (Illumina Infinium HumanMethylation27 BeadArray) and single nucleotide polymorphisms (SNPs, Illumina Infinium HD Human610-Quad BeadArray). We employed a three-step filtering procedure, followed by the Causal Inference Test (CIT), to distinguish CpG sites that mediate genetic risk, from those that are consequential or independently acted on by genotype. Controlling for the estimated distribution of immune cells and other key covariates, we identified 1,993 out of 25,926 (7.7%) CpGs that were significantly differentially methylated between cases and controls (FDR, q < 0.05). The relationship between methylation and case-control status among these 1,993 CpGs was found to be highly consistent with the results of an independent study. Implementation of the CIT test revealed 13 CpG/SNP pairs, comprising 13 unique CpGs and 17 unique SNPs, which represent potential methylation-mediated relationships between genotype and EOC risk. These findings provide additional insight into EOC etiology and may serve as novel biomarkers for EOC susceptibility.

Citation Format: Devin C. Koestler, Prabhakar Chalise, Mine S. Cicek, Julie M. Cunningham, Sebastian Armasu, Melissa C. Larson, Jeremy Chien, Matthew Block, Kimberly R. Kalli, Thomas A. Sellers, Ellen L. Goode, Brooke L. Fridley. Integrative genomic analysis identifies epigenetic marks that mediate genetic risk for epithelial ovarian 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 260. doi:10.1158/1538-7445.AM2014-260