Cancer Chemistry最新文献

{"title":"Abstract 3621: Targeted hyaluronic acid nanoparticles improve treatment response in pancreatic cancer","authors":"M. R. Jajja, Lei Zhu, Dazhi Wang, C. Staley, B. El-Rayes, D. Kooby, Lily Yang","doi":"10.1158/1538-7445.SABCS18-3621","DOIUrl":"https://doi.org/10.1158/1538-7445.SABCS18-3621","url":null,"abstract":"","PeriodicalId":9563,"journal":{"name":"Cancer Chemistry","volume":"21 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81822214","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Abstract 983: Antibody-drug conjugates of NAMPT inhibitors: Discovery, optimization, and preclinical characterization","authors":"C. Neumann, K. Olivas, K. Wang, A. Waight, David W Meyer, Luke V Loftus, Margo Zaval, Martha E. Anderson, Steven Jin, Julia H Cochran, J. Simmons, Paul G Pittman, Fu Li, Michelle Ulrich, Abbie Wong, Weiping Zeng, R. Lyon, P. Senter","doi":"10.1158/1538-7445.AM2019-983","DOIUrl":"https://doi.org/10.1158/1538-7445.AM2019-983","url":null,"abstract":"Nicotinamide phosphoribosyltransferase (NAMPT) regulates the biosynthesis of NAD from nicotinamide via a salvage biosynthetic pathway. Inhibition of NAMPT depletes cellular NAD levels leading to disruption of energy metabolism and cell death. Non-targeted small molecule NAMPT inhibitors have demonstrated poor tolerability in clinical trials and in preclinical models, including cardiac and retinal toxicities in rats. In an effort to improve the therapeutic window of this drug class, we pursued a targeted-delivery approach using antibody-drug conjugates. Through a medicinal chemistry effort, we identified novel NAMPT inhibitors that incorporate chemical functionality in the solvent-exposed terminus to allow construction of enzyme-cleavable drug linkers. Additionally, we applied a pyridinium-based linker strategy that allows for traceless linker attachment through a conserved nicotinamide-mimetic moiety of NAMPT inhibitors. Candidate molecules were evaluated for NAMPT binding affinity and cellular cytotoxicity as free drugs, and for cellular cytotoxicity as ADCs with the alternate linker strategies. Comparisons across inhibitors and linker strategies provide insight into optimal design of cleavable drug linkers for this class of drugs. In vitro, the ADCs deplete NAD and lead to downstream ATP depletion in a time-dependent manner. In vivo evaluation using human tumor xenografts shows translation of the pharmacodynamic effect resulting in tumor regression in models of Hodgkin lymphoma, non-Hodgkin lymphoma, and acute myeloid leukemia. Toxicology studies in Sprague Dawley rats demonstrate excellent tolerability at active doses, with no observable cardiac or retinal toxicities at the highest tested doses in single- and multi-dose regimens. These findings detail the development of a novel payload class and optimized linker strategy for use with antibody-drug conjugates, and demonstrate a preclinical efficacy and safety profile to support continued efforts toward clinical therapeutics. Citation Format: Chris Neumann, Kathleen C. Olivas, Kung Pern Wang, Andrew B. Waight, David W. Meyer, Luke V. Loftus, Margo C. Zaval, Martha E. Anderson, Steven Jin, Julia H. Cochran, Jessica K. Simmons, Paul G. Pittman, Fu Li, Michelle L. Ulrich, Abbie Wong, Weiping Zeng, Robert P. Lyon, Peter D. Senter. Antibody-drug conjugates of NAMPT inhibitors: Discovery, optimization, and preclinical characterization [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 983.","PeriodicalId":9563,"journal":{"name":"Cancer Chemistry","volume":"4 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82217863","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Abstract 988: Synthesis and preclinical evaluation of dual-stimuli responsive doxorubicin prodrug activated by histone deacetylases and cathepsin L","authors":"S. Punganuru, H. Madala, Viswanath Arutla, K. Srivenugopal","doi":"10.1158/1538-7445.AM2019-988","DOIUrl":"https://doi.org/10.1158/1538-7445.AM2019-988","url":null,"abstract":"Doxorubicin (DOX) an anthracycline is a leading anticancer drug with a broad spectrum of activity against numerous solid and hematologic malignancies. However, its clinical application is limited by lower efficacy, severe cardiotoxicity and occurrence of secondary malignancies. There is an urgent need for eliminating the Dox adverse effects while retaining its anticancer efficacy. One of the major goals of cancer therapy is the selective targeting of malignancies over normal tissues. One way to avoid these severe adverse reactions is to develop tumor-targeted prodrugs that are converted to active antitumor drugs at tumor sites in the presence of enzymes that are overexpressed human cancers. Among these, the histone deacetylases (HDACs) and cathepsin L (CTSL) are highly expressed in cancer cells and are considered as potential cancer-specific targets. HDACs are critical enzymes involved in the regulation of histone and non-histone proteins and elevated HDACs in tumor cells are known to be closely associated with tumor initiation, progression, and metastasis. Similarly, the lysosomal cysteine protease CTSL plays key roles at multiple stages of tumor progression and metastasis. In the present study, we developed a new prodrug by coupling an acetylated lysine group to doxorubicin (Lys(Ac)-Dox), a masked cytotoxic agent, which is consecutively activated by HDACs and a CTSL to liberate doxorubicin. We first verified whether Lys(Ac)-Dox could be specifically cleaved by HDACs and CTSL in vitro. The results showed that after incubating with HDACs and CTSL at 37 °C for 20 h, the hydrolysis of Lys(Ac)-Dox reached 99%, suggesting that Lys(Ac)-Dox could be successfully cleaved by the target enzymes. To prove that the Lys(Ac)-Dox would have a much improved growth-inhibitory effect against cancer cells, the cytotoxicity of free DOX and Lys(Ac)-Dox against lung cancer cell lines normal human lung epithelial cell line was determined. The dose-response curves obtained from the cell lines tested indicated that Dox was equally cytotoxic against both cancer and normal cells. In contrast, Lys(Ac)-Dox highly cytotoxic against cancer cells and non-toxic to the normal counterparts. To measure the in vivo anticancer efficacy of Lys(Ac)-Dox vis-vis Dox, we developed subcutaneous xenografts by injecting human lung cancer A549 and H460 cells in nude mice. Lys (Ac)-Dox and Dox were administered daily i.p. at 5 mg/kg. The prodrug showed a significantly higher (>2-fold) tumor regression than Dox. A diminished circulating reticulocyte counts from whole blood after Dox treatment is known to reflect the hematological toxicity caused by the drug. Only Dox caused significant reticulocyte ablation while the prodrug did not, validating our drug design. Biochemical tests involving topo II inhibition and ROS production by the prodrug are in progress (supported by CPRIT grant RP 170207 to KSS). Note: This abstract was not presented at the meeting. Citation Format: Surendra R. Punganuru, ","PeriodicalId":9563,"journal":{"name":"Cancer Chemistry","volume":"17 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88412213","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Abstract 1861: Aviscumine (ME-503) suppresses the growth of melanoma by potentially targeting c-Myc pathway","authors":"Peiying Yang, Tara Conway, P. Rhea, Dongmei Chen, Bo Wei, Jibin Ding, H. Lentzen, J. McQuade","doi":"10.1158/1538-7445.AM2019-1861","DOIUrl":"https://doi.org/10.1158/1538-7445.AM2019-1861","url":null,"abstract":"Aviscumine, a recombinant mistletoe lectin I, is produced in E. coli and has been evaluated for its antitumor activities in various experimental in-vitro and in-vivo tumor models as well as in clinical trials. A phase II trial demonstrated the safety and efficacy of Aviscumine in pretreated patients with metastatic melanoma (stage IV). However, the mechanism(s) underlying the effect of Aviscumine in melanoma is inconclusive. Here, the antitumor activities and relevant mode of actions of Aviscumine were investigated in human melanoma A375, mouse melanoma Yummer and B16 cells as well as their relevant xenograft animal models. Cells were treated with Aviscumine (0-20 ng/mL) for 48 and 72 hrs, and cell proliferation was measured by MTT assay. Alteration of cell growth regulatory proteins and cell signaling proteins were determined by Reverse Phase Proteomic Array (RPPA) and validated with western blotting. Aviscumine exerted much stronger anti-proliferative activity in both A375 and Yummer cells with IC50 of 0.18 ± 0.03 ng/ml and 0.41 ± 0.06 ng/ml, respectively than that of B16 cells (IC50 15.93 ± 3.48 ng/ml). In A375 cells, Aviscumine significantly increased subG0/G1 population suggesting Aviscumine treatment led to apoptotic and necrotic cell death. Additionally, downregulation of various proteins associated with apoptotic cell death (pCDK1, pRB, MCl-1) was also observed by RPPA. Furthermore, Aviscumine significantly decreased c-Myc protein expression in a concentration-dependent manner measured by both RPPA and western blot. Interestingly, baseline c-Myc protein expression was much higher in the Aviscumine-sensitive A375 and Yummer cells than that in the Aviscumine-resistant B16 cells. Finally, the effects of Aviscumine on tumor growth were tested via subcutaneous injection (30 ng/kg, twice per week for three weeks) in mice bearing A375 or B16 melanoma. At 3 weeks, A375 tumors were markedly smaller in Aviscumune treated mice (383.8 ± 102.2 mg) than in the control-treated group (922.4 ± 296.1 mg). c-Myc protein expression was also significantly reduced (62% vs. control) in Aviscumine treated A375 tumors, as were levels of multiple downstream metabolites (pyruvate, malate, and glutamate) (p Citation Format: Peiying Yang, Tara Conway, Patrea Rhea, Dongmei Chen, Bo Wei, Jibin Ding, Hans Lentzen, Jennifer McQuade. Aviscumine (ME-503) suppresses the growth of melanoma by potentially targeting c-Myc pathway [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 1861.","PeriodicalId":9563,"journal":{"name":"Cancer Chemistry","volume":"8 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83932383","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Abstract 1864: Verticillin A causes DNA damage and apoptosis in high grade serous ovarian cancer","authors":"A. Salvi, Julia R. Austin, D. Lantvit, J. Burdette","doi":"10.1158/1538-7445.AM2019-1864","DOIUrl":"https://doi.org/10.1158/1538-7445.AM2019-1864","url":null,"abstract":"High grade serous ovarian cancer (HGSOC) is the most lethal gynecological malignancy affecting women worldwide and the fifth most common cause of cancer related deaths among U.S. women. New targeted therapies are needed to prevent HGSOC progression and metastasis related lethality from the disease. The goal of this study was to test the novel natural compound, Verticillin A, for its anticancer properties and mode of action in HGSOC cells. Verticillin A is an epipolythiodioxopiperazine (ETP) alkaloid that is isolated from several terrestrial and marine filamentous fungi and has been shown to be cytotoxic in several cancer cell lines including OVCAR8, OVCAR4 and Kuramochi. Our data indicated that Verticillin A treatment caused cytotoxicity in HGSOC cell lines in a dose-dependent manner. Furthermore, treatment with Verticillin A in HGSOC cell line OVCAR8 and OVCAR4 enhanced apoptosis, which was demonstrated by PARP cleavage and Annexin V/ Propidium iodide staining. To determine whether Verticillin A caused in vivo tumor growth inhibition, OVCAR8-RFP cells were xenografted in mice to form tumors and the mice were treated with Verticillin A. Encapsulated nanoparticles of Verticillin A decreased tumor growth in vivo and had low cytotoxicity compared to the naked drug. RNA-Seq analysis was performed with OVCAR8 cells treated with Verticillin A and the data found an upregulation of apoptosis signaling pathway and oxidative stress response and downregulation of cancer stemness signaling pathways. A proteomic histone profiling performed in OVCAR8 cells indicated that Verticillin A caused epigenetic modifications with global changes in histone methylation and acetylation marks. Thus, our study identifies Verticillin A as a novel epigenetic modifier in ovarian cancer cells and indicates therapeutic potential for treatment of HGSOC. Note: This abstract was not presented at the meeting. Citation Format: Amrita Salvi, Julia Austin, Daniel Lantvit, Joanna Burdette. Verticillin A causes DNA damage and apoptosis in high grade serous ovarian cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 1864.","PeriodicalId":9563,"journal":{"name":"Cancer Chemistry","volume":"24 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82845031","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Abstract 2749: Defining structure activity relationships for GPCR engagement and anti-cancer efficacy of imipridone small molecules","authors":"V. Prabhu, A. Kawakibi, Neel S. Madhukar, L. Anantharaman, Sean W. Deacon, N. Charter, M. Garnett, U. McDermott, C. Benes, W. Oster, O. Elemento, M. Stogniew, J. Allen","doi":"10.1158/1538-7445.AM2019-2749","DOIUrl":"https://doi.org/10.1158/1538-7445.AM2019-2749","url":null,"abstract":"G protein-coupled receptors (GPCRs) represent the most widely exploited superfamily of drug targets for FDA-approved therapies for many diseases, however, these receptors are underexploited for oncology. ONC201 is a selective antagonist of GPCRs dopamine receptor D2 (DRD2) and DRD3 that has been shown to induce tumor regressions with a benign safety profile in high grade glioma patients. ONC201 (benzyl-2-methylbenzyl-imipridone) is the founding member of the imipridone class of small molecules that share a unique tri-heterocyclic core chemical structure. Imipridones share several chemical and biological properties that are desirable drug-like characteristics: oral administration, wide therapeutic window, chemical stability and blood brain barrier penetrance. In this study, we profiled a series of imipridones for GPCR engagement and anti-cancer efficacy. Several imipridones were screened against a large panel of human GPCRs using a β-arrestin recruitment assay. The imipridones tested resulted in GPCR agonist/antagonist activity (threshold set at >20% activity) that was heterogenous, but exclusive among Class A GPCRs that represent the largest class. Minor chemical modifications to the ONC201 chemical structure caused large shifts in agonist versus antagonist activity and selectivity for GPCRs. Specifically, switching the ONC201 imipridone core from an angular to a linear isomer resulted in loss of DRD2 antagonist activity and impaired inhibition of cancer cell viability, indicating the imipridone core structure is critical for GPCR engagement and anti-cancer effects. The addition of electron withdrawing groups (e.g. di- or tri-halogen substitution) to the methyl benzyl ring improved potency for GPCR engagement and anti-cancer effects, but not for the benzyl ring. Loss of the benzyl ring impaired anti-cancer effects. Among all of the GPCR hits identified, maximal variance in imipridone GPCR engagement was identified for DRD2/DRD3 antagonism and GPR132 agonism that were prioritized considering their known biological relevance in oncology. ONC206 (benzyl-2,4-difluoromethylbenzyl-imipridone) emerged as the most selective and potent antagonist for D2-like dopamine receptors that are overexpressed and critical for survival in several cancers. ONC212 (benzyl-4-trifluoromethylbenzyl-imipridone) was the most selective and potent agonist for tumor suppressor GPR132. Both compounds were tested in the GDSC panel of >1000 cancer cell lines and demonstrated broad spectrum nanomolar inhibition of cancer cell viability and a wide therapeutic window. GPCR target expression correlated with anti-cancer efficacy in the GDSC panel for both compounds, providing potential biomarkers of response. Thus, chemical derivatization of ONC201 has generated a class of novel GPCR-targeting agents with promising preclinical efficacy and safety profiles in oncology. Citation Format: Varun V. Prabhu, Abed Rahman Kawakibi, Neel S. Madhukar, Lakshmi Anantharaman, Sean Deacon, Neil S. ","PeriodicalId":9563,"journal":{"name":"Cancer Chemistry","volume":"71 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90481102","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Abstract 1867: Liver and urinary bladder cancers: The modifying role of aqueous leaf extract ofTerminalia glaucescensPlanch. ex Benth","authors":"J. O. Olugbami, R. Damoiseaux, J. Gimzewski, O. Odunola","doi":"10.1158/1538-7445.AM2019-1867","DOIUrl":"https://doi.org/10.1158/1538-7445.AM2019-1867","url":null,"abstract":"Background: The aggressive and asymptomatic nature of liver cancer etiology in blacks is well documented. Furthermore, in Egypt, bladder cancer accounts for as many as 31% of all cancer cases, while in the US, the incidence in whites is higher than in blacks. There has been an increased search for phytochemicals, such as capsaicin (a bioactive component of hot peppers), which are easily available, and possess chemopreventive and chemotherapeutic activities. We therefore investigated the potential scientific relevance of aqueous leaf extract of Terminalia glaucescens (ALET) in cancer management. Terminalia glaucescens has been ethnomedicinally associated with various biological and therapeutic properties. Methods: Total flavonoid and phenolic contents of ALET were assessed spectrophotometrically using gallic acid and quercetin as standards, in addition to its free-radical-scavenging activity involving 2,2-diphenyl-1-picrylhydrazyl assay with butylated hydroxytoluene and vitamin C as reference compounds. The hydroxyl-radical-scavenging and reducing-power activities were correspondingly assessed. In addition, antiproliferative activities of ALET in comparison with capsaicin on normal and cancer cell lines of human liver (THLE-3 and HepG2) and urinary bladder (HUC-PC and MC-T11) were evaluated using fluorometry. Luminometry was used to determine ATP concentrations, caspase 3/7 activities, glutathione status, and mitochondrial functions. Results: Quantitative phytochemical assessments indicate the predominance of phenolic compounds (599.61 ± 6.14 µg gallic acid equivalents per mg of ALET) as compared with flavonoids (144.27 ± 3.44 µg quercetin equivalents per mg of ALET). ALET possesses comparable free-radical-scavenging, antioxidant and reducing-power activities in comparison to the standards. Treatment of the four cell lines with ALET for three days results in the following percent total cells: THLE-3 (30.13% at 24 h; 5.65% at 48 h; 5.43% at 72 h), HepG2 (31.09% at 24 h; 4.75% at 48 h; 1.41% at 72 h), HUC-PC (7.33% at 24 h; 2.35% at 48 h; 1.74% at 72 h), and MC-T11 (19.79% at 24 h; 9.20% at 48 h; 0.29% at 72 h). Assessment of the ATP levels after 24 h treatment with ALET resulted in a concentration-dependent depletion with a remarkable effect on HUC-PC and MC-T11 urinary bladder cells. ALET specifically caused a concentration-dependent decrease in caspase 3/7 activities and glutathione levels in HepG2 cells. ALET seems more toxic to the mitochondria at higher concentrations as compared with capsaicin. Conclusions: ALET could be a natural source of mitocans for the treatment of cancers. Citation Format: Jeremiah Olorunjuwon Olugbami, Robert Damoiseaux, James Kazemier Gimzewski, Oyeronke Adunni Odunola. Liver and urinary bladder cancers: The modifying role of aqueous leaf extract of Terminalia glaucescens Planch. ex Benth [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Ph","PeriodicalId":9563,"journal":{"name":"Cancer Chemistry","volume":"75 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83817385","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Abstract 4543: Proteomic characterization of AXL kinase inhibitors and signaling pathways","authors":"A. Majumder, Guolin Zhang, Emma Adhikari, B. Fang, E. Welsh, J. Koomen, E. Haura","doi":"10.1158/1538-7445.AM2019-4543","DOIUrl":"https://doi.org/10.1158/1538-7445.AM2019-4543","url":null,"abstract":"AXL is an attractive drug target because of its role in EMT-mediated resistance to EGFR tyrosine kinase inhibitor (TKI) in lung cancer (LC). Lack of genetic alterations and the role of stroma-mediated AXL activation in cancer cells, underscore the need to better characterize AXL TKIs, understand their effects on signaling and phenotype of cells, and develop assays to visualize active AXL signaling complexes. For this, 25 LC cells were analyzed for total (t) and phosphorylated (p) AXL expression. AXL TKIs, RXDX106, R428 and Cabozantinib, were profiled using western blotting (WB), viability assay and activity-based protein profiling (ABPP). Phosphoproteins (pSTY) altered by RXDX106 were identified using mass spectrometry. Effects of RXDX106 on signaling, viability and migration of LC cells were also evaluated. Cell line models of EMT-mediated acquired drug resistance, treated with a combination of AXL and EGFR TKIs, were analyzed for changes in signaling, cell viability and EMT. Immunoprecipitation (IP) identified adaptors of AXL signaling, and Proximity Ligation Assays (PLA) were developed to detect these active complexes in situ. H1299 cells, expressing highest levels of p and t AXL among the LC lines screened, was used in this study. RXDX106 and Cabozantinib potently inhibited pAXL in H1299 cells, but did not affect cell viability at these doses. R428 reduced cell viability at doses that did not efficiently inhibit pAXL, suggesting AXL independent phenotypic effects. Our ABPP data shows that apart from AXL, these TKIs target other overlapping and distinct subsets of proteins. R428 has the highest number of off targets and its unique ability to inhibit the FoxO pathway may explain the AXL independent phenotypic effects of R428. The pSTY data shows that RXDX106 deregulates phosphorylation of proteins involved in PI3K signaling, receptor endocytosis and cell migration pathways in H1299 cells. WB and phenotypic assays support these results by showing that RXDX106 inhibits pAXL, downstream pAKT but not pERK, and migration/invasion in these cells. In EGFR TKI resistant cells, EGFR and AXL TKI combination fails to alter downstream signaling, cell viability or EMT. Consistent with the WB and pSTY analyses, IP identifies PI3KR1 as an AXL interactor. PLAs to detect active AXL:PI3KR1 and AXL:pY100 signaling complexes show high basal PLA foci in H1299 and Calu1 cells that are abrogated by AXL TKI. HCC827 cells, which lack ligand independent pAXL, do not show significant labeling by either PLA. Overall, we demonstrate that different AXL TKIs have distinct target profiles and that inhibition of AXL suppresses downstream PI3K/AKT signaling and migration/ invasion of LC cells. We also show that AXL TKI fails to suppress downstream signaling, cell viability or EMT in EGFR TKI resistant cell lines. We have also established a PLA to annotate AXL adaptor foci that could be developed as a tool to measure drug-targetable active AXL complexes in patient tissues. Citat","PeriodicalId":9563,"journal":{"name":"Cancer Chemistry","volume":"72 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89562146","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Abstract 4541: Malignant and non-malignant cells from primary tumor and lymph node metastasis ecosystems show different behavior for patient-associated protein signatures in head and neck cancer","authors":"A. Busso-Lopes, C. Rivera, B. Mello, L. Villa, W. González-Arriagada, A. Leme","doi":"10.1158/1538-7445.SABCS18-4541","DOIUrl":"https://doi.org/10.1158/1538-7445.SABCS18-4541","url":null,"abstract":"","PeriodicalId":9563,"journal":{"name":"Cancer Chemistry","volume":"16 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73902408","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Abstract 4456: Discovery of E7766: A representative of a novel class of macrocycle-bridged STING agonists (MBSAs) with superior potency and pan-genotypic activity","authors":"A. Endo, Dae-Shik Kim, Kuan-Chun Huang, M. Hao, S. Mathieu, Hyeong-Wook Choi, U. Majumder, Xiaojie Zhu, Yongchun Shen, Kristen Sanders, Thomas Noland, D. Chandra, Yu Chen, Karen Tendyke, K. Loiacono, D. Kolber-Simonds, Rongrong Jiang, Vaishali Dixit, J. Hutz, John Y. Wang, Xingfeng Bao, F. Fang, N. Sarwar","doi":"10.1158/1538-7445.SABCS18-4456","DOIUrl":"https://doi.org/10.1158/1538-7445.SABCS18-4456","url":null,"abstract":"Introduction STING (stimulator of interferon genes) is an emerging target for cancer immunotherapy. 2’,39-cGAMP, a natural cyclic dinucleotide (CDN) STING agonist, and its phosphorothioate analogs, have drawn broad attention as lead molecules for STING targeted drug discovery. These CDNs, however, lack efficacy in some common STING genotypes disproportionally represented in non-Caucasians. Moreover, such CDNs have not fully addressed liability in chemical/metabolic stability. Here we report our chemistry approach to control STING agonist conformation to enhance binding affinity across all common STING genotypes and broaden the therapeutic potential of such compounds. Methods Our SBDD approach started with analysis of the binding pocket and key protein-ligand interactions to prioritize a focused set of analogs for chemical synthesis. Systematic SAR was built upon in vitro assays for STING binding affinity and activation of STING genotypes. X-ray single crystal structures were established for STING and diverse analogs, in free and bound states, to provide structural insight for rational analog design. Results Structural modeling was refined to evaluate different binding modes and dynamic conformational changes in the STING-ligand interface. We observed that STING-bound CDNs had the two ancillary nucleobases specifically oriented in close proximity with parallel pi-pi stacking and discovered that covalently linking the nucleobases advantageously pre-organize the bioactive constrained conformation for enhanced STING affinity. Our discovery established a novel class of macrocycle-bridged STING agonists (MBSAs). E7766, a representative of Eisai MBSA platform, shows superior in vitro activity against all the major human STING genotypes over reference CDNs, most distinctly in STINGREF. E7766 co-crystal structures with STINGWT and STINGREF provide structural basis for the added benefit of the topological novelty. The macrocyclic linker bridging the top of nucleobases perturbs the STING lid loop conformation and create new and specific interactions with both genotypes. In twelve subcutaneous tumor models in immune competent mice, single intra-tumoral injections achieved either complete regression or significant tumor growth delay with no serious adverse effect. E7766 also shows excellent chemical and metabolic stability, presumably conferred by conformational rigidity of the unique macrocycle bridge. More biological characterization of E7766 can be found in abstract #. Conclusion Eisai successfully discovered E7766, a representative of a novel class of macrocycle-bridged STING agonist topologically distinct from conventional STING agonists. E7766 demonstrated pan-genotypic STING activation, potent anti-cancer activities and excellent chemical and metabolic stability for further development. Citation Format: Atsushi ENDO, Dae-Shik Kim, Kuan-Chun Huang, Ming-Hong Hao, Steven Mathieu, Hyeong-wook Choi, Utpal Majumder, Xiaojie Zhu, Yongchun Shen, Kristen Sande","PeriodicalId":9563,"journal":{"name":"Cancer Chemistry","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84278143","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}