bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 4074: Permeability changes and effect of chemotherapy in brain adjacent to tumor in an experimental model of brain metastases of breast cancer
Authors: Mohammad Afroz Shareef , Adkins Chris E. , Shah Neal , Aljammal Rawaa , Griffith Jessica , Lockman Paul R.
Published: July 2017

Background: Brain metastases vasculature is compromised and more permeable than that of vasculature in normal brain. Unfortunately, little is known about vascular permeability changes in brain adjacent to tumor (BAT). It is critical to understand the potential changes as chemotherapy penetration and accumulation brain tumors positively correlate with breakdown of the brain vasculature. Herein, we evaluate quantitatively measure permeability, drug accumulation and cytotoxicity in normal brain that is adjacent (<500 microns) to a tumor.

Methods: The subclone population of brain seeking metastatic breast cancer cells (MDA-MB-231Br) were injected into the left ventricle of female NuNu mice. Mice were given a chemotherapeutic regimen of vinorelbine (10mg/kg), erubilin (1.5mg/kg) or docetaxel (10mg/kg). Progression occurred until neurological compromise was noted, at which time animals were injected with texas red 625 Da(TR) and texas red dextran 3kDa (TRD). Dye concentrations (measuring passive permeability changes) were determined in lesions and the BAT using quantitative fluorescent microscopy. Chemotherapeutic induced cytotoxicity was observed by staining for activated astrocytes and DNA damage in neurons, glia and endothelia.

Results: We observed permeability of TR is highly heterogeneous both within and between the tumors (normal brain Kin TR: 1.2 x10-5)with 2-40-fold increase in permeability over normal brain region. TR concentrations in BAT (100µm from tumor edge) is consistently 40% of the tumor but significantly higher than that of normal brain and TR permeability in BAT increased 1-2.5-fold over normal brain. The permeability of TRD in tumor increased 2.7- 8.4-fold over normal brain, whereas in BAT, the permeability increased 1-1.6-fold over normal brain. We also observed animals treated with chemotherapy showed activated astrocytes in BAT, along with some cellular death. In vehicle treated animals there were little activated astrocytes and little cell death in the BAT.

Conclusions: Our data suggests that the tracer and drugs accumulate in regions around tumors in the brain which result in neurotoxic changes.

Citation Format: Afroz Shareef Mohammad, Chris E. Adkins, Neal Shah, Rawaa Aljammal, Jessica Griffith, Paul R. Lockman. Permeability changes and effect of chemotherapy in brain adjacent to tumor in an experimental model of brain metastases of breast cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4074. doi:10.1158/1538-7445.AM2017-4074
Abstract 4077: Application of drug sensitivity and resistance testing to identify novel therapeutic agents for Down syndrome patients with AML
Authors: Patel Apurvi R. , Montoya Justin J. , Wai Daniel H. , Lee David W. , Arceci Robert J. , Azorsa David O.
Published: July 2017

Patients with Down’s syndrome who develop acute myeloid leukemia (AML) are at increased risk of toxicity secondary to chemotherapy regimens. These patients are harder to treat with conventional therapies at relapse. Overall, the use of targeted drug therapy is rising in the pediatric oncology field. Development of drug sensitivity and resistance test allows identification of specific targeted therapies for patient’s with difficult to treat leukemia. Our laboratory is working on the development of a drug sensitivity and resistance screening assay that would provide functionally relevant drug response data of the patient’s leukemia cells. Development of this assay included the preparation of pre-dosed drug library plates allowing for rapid initiation of the assay. AML cells are then added to the plate and treated for 72 hours after which cell viability was determined. Previous work in our laboratory tested a library of 56 anti-cancer and targeted agents on a panel of 16 AML cell lines that included two Down’s syndrome AML cell lines CMK and CMY. Drug dose response data including IC50 values and Area Under the Curve (AUC) were calculated for each cell line. Hierarchical clustering was performed to determine similar responses between cell lines. Down’s syndrome cell lines, CMK and CMY were found to be resistant to most conventional chemotherapeutic agents, but susceptible to targeted therapies such as Navitoclax and 17-AAG. We further tested several cell lines with the drug sensitivity and resistance assay under hypoxic conditions. Our screening results showed improved sensitivity of the CMK and CMY cells to Navitoclax and 17-AAG under normoxic and hypoxic conditions. Validation of the screening results was done using a 10-concentration drug dose response assay. Future studies will explore the mechanism by which the Down’s syndrome AML cells have increased sensitivity to these targeted agents under both normoxic and hypoxic conditions. Furthermore, we will investigate the activity of combinations of these targeted therapies with conventional therapies. The results from these studies could lead to the establishment of improved therapeutic regimens for Down’s syndrome patients with AML.

Citation Format: Apurvi R. Patel, Justin J. Montoya, Daniel H. Wai, David W. Lee, Robert J. Arceci, David O. Azorsa. Application of drug sensitivity and resistance testing to identify novel therapeutic agents for Down syndrome patients with AML [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4077. doi:10.1158/1538-7445.AM2017-4077
Abstract 4078: Tumors with class 3 BRAF mutants are sensitive to the inhibition of activated RAS
Authors: Yao Zhan , Yaeger Rona , Rodrik-Outmezguine Vanessa S. , Tao Anthony , Torres Neilawattie M. , Chang Matthew T. , Drosten Matthias , Zhao Huiyong , Cecchi Fabiola , Hembrough Todd , Michels Judith , Baumert Hervé , Miles Linde , Campbell Naomi M. , Stanchina Elisa de , Solit David B. , Barbacid Mariano , Taylor Barry S. , Rosen Neal
Published: July 2017

Approximately two hundred mutant BRAF alleles have been identified in human tumors. Physiologic activation of RAF isoforms requires RAS-dependent induction of their dimerization. Activating BRAF mutants cause ERK dependent feedback inhibition of RAS.GTP and are RAS independent. As we have shown previously, they signal either as active monomers or RAS-independent constitutively active dimers. Here, we characterized a third class of BRAF mutants—those that have impaired kinase activity or are kinase dead. These class 3 BRAF mutants are sensitive to ERK-mediated feedback and they function in a RAS-dependent manner. In tumors, they bind more tightly to active RAS, thus enhancing their heterodimerization with CRAF. This is associated with the amplification of RAS-RAF-MEK-ERK signaling.

Since these mutants are sensitive to ERK-dependent feedback inhibition of RAS, their enhancement of ERK signaling in tumors requires concurrent dysregulation of RAS activation. Thus, melanomas with Class 3 mutations usually harbor coexistent RAS mutation or NF1 mutants/deletion, whereas receptor tyrosine kinase signaling is activated in lung and colorectal cancers with these mutants. Our model suggests that these tumors will be sensitive to the inhibition of RAS activation. Currently, no direct inhibitors of RAS activation are available. However, in support of this idea, inhibitors of activated RTK signaling in carcinomas with Class 3 BRAF mutants and wild type RAS is sufficient to markedly inhibit ERK signaling and their growth in in vivo murine models and in patients. We have thus defined a third subset of BRAF mutants, which is RAS-dependent. Tumors harboring such mutants are sensitive to tyrosine kinase inhibitors in tumors expressing wild type RAS and NF1.

Citation Format: Zhan Yao, Rona Yaeger, Vanessa S. Rodrik-Outmezguine, Anthony Tao, Neilawattie M. Torres, Matthew T. Chang, Matthias Drosten, Huiyong Zhao, Fabiola Cecchi, Todd Hembrough, Judith Michels, Hervé Baumert, Linde Miles, Naomi M. Campbell, Elisa de Stanchina, David B. Solit, Mariano Barbacid, Barry S. Taylor, Neal Rosen. Tumors with class 3 BRAF mutants are sensitive to the inhibition of activated RAS [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4078. doi:10.1158/1538-7445.AM2017-4078
Abstract 4083: Basic mechanisms of Vernonia amygdalina exert antitumor activities in breast cancer cells
Authors: Yedjou Clement G. , Tchounwou Paul B.
Published: July 2017

Breast cancer continues to represent the largest cause of mortality in the world especially among women. It is estimated that cancer kills more women in the USA than any other illness and it is also the leading cause of death among all Americans. Traditional medicine represents the first-choice of healthcare treatment for at least 80% of people living in developing countries. Preliminary studies from our laboratory have shown that a novel natural product, extracts of Vernonia amygdalina (VA) leaf exerts DNA-damaging anticancer activities against breast cancer. There is a need to develop targeted approaches for the treatment of human breast cancer. Therefore, the goal of this research was to determine the therapeutic mechanisms of V. amygdalina leaf extracts as anti-cancer agent in the management of breast cancer. To achieve our goal, cell viability, live and death cells were determined by trypan blue exclusion test. The extent of oxidative cell/tissue damage was determined by measuring malondialdehydes (MDA) levels. Expression of p53 tumor suppressor gene was assessed both by immunofluorescent and western blot analyses. Cell apoptosis was measured both by flow cytometry analysis and DNA laddering assay. Data obtained from the Trypan blue indicated that V. amygdalina significantly reduced the viability of MCF-7 cells in a dose-dependent response, showing gradual increase in the loss of viability in V. amygdalina-treated cells due to membrane damage. We observed an up-regulation of p53 tumor suppressor gene in V. amygdalina-treated cells compared to the control. Flow cytometry data showed a strong dose-response relationship between V. amygdalina exposure and caspase-3 positive cells. These results were confirmed by data of DNA laddering assay showing a clear evidence of nucleosomal DNA fragmentation in V. amygdalina-treated cells. Collectively, data generated from the present study demonstrated that V. amygdalina destroys breast cancer cells by reducing the percentage of cell viability and inducing apoptosis through up-regulation of p53 tumor suppressor gene, activation of caspase-3, and induction of nucleosomal DNA fragmentation associated with the formation of MDA, a by-product of lipid peroxidation and biomarker of oxidative stress. This result suggests that V. amygdalina treatment may be a good anti-cancer candidate for the treatment of breast cancer. Research supported by NIH Grant No. NIMHDG12MD007581)

Citation Format: Clement G. Yedjou, Paul B. Tchounwou. Basic mechanisms of Vernonia amygdalina exert antitumor activities in breast cancer cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4083. doi:10.1158/1538-7445.AM2017-4083
Abstract 4090: Preclinical pharmacokinetics of CASC-578, a novel, selective, potent, and orally bioavailable small molecule checkpoint kinase 1 inhibitor
Authors: Leviten Dina , Sierra Teresa , Dozier Ashley , Boyce Richard , Boyle Bob , Peterson Scott , Vo Alex C.
Published: July 2017

Introduction: Checkpoint kinase 1 (Chk1) is a serine/threonine protein kinase that regulates cell division in response to genotoxic stress by arresting cell cycle progression in the S & G2 phases. Pharmacological inhibition of Chk1 is proposed to selectively uncouple the completion of DNA replication from G2/M phase transition in tumor cells that have impaired DNA damage response networks, resulting in mitotic catastrophe and cell death. CASC-578 is a novel small molecule inhibitor of Chk1 that is selective, highly potent and orally bioavailable in multiple preclinical species.

Methods: The in vitro ADME properties of CASC-578 were evaluated, including in vitro intrinsic microsomal clearance, Caco2 permeability, plasma protein binding and stability, blood to plasma partitioning, cytochrome P450 inhibition and induction, and transporter inhibition. Pharmacokinetic studies of CASC-578 were conducted in mice, rats, and cynomolgus monkeys as either single dose (IV and/or PO) or repeat dose (PO only). Multiple oral dose pharmacokinetic studies were conducted in mice, rats and cynomolgus monkeys for 5-7 days.

Results: CASC-578 is highly bound in plasma protein across all species. The apparent permeability is high in Caco2 bi-directional transport study and correlated well with a rapid absorption profile observed in vivo. CASC-578 is not a substrate of P-glycoporotein (efflux =1). There was no direct nor time dependent inhibition on human CYP450 enzymes, and only a slight induction of CYP3A4 was seen at 10 uM drug concentration in a transporter cell-based induction assay. In all animal species, CASC-578 exhibited species-dependent systemic clearance resulting from both phase I and phase II metabolism, and a moderate to high volume of distribution. The elimination kinetics appeared to be monophasic. Oral bioavailability was high in all species studied (>60% F). There was no significant difference in the pharmacokinetics of the drug between genders. Maximal plasma concentration and total drug exposure (AUC) appeared to be proportional from repeat dose studies. Overall, CASC-578 has very desirable drug-like properties and ideal pharmacokinetics for an oral once daily drug, and represents a suitable candidate for clinical development as a novel potential therapeutic approach for the treatment of solid and hematological malignancies

Citation Format: Dina Leviten, Teresa Sierra, Ashley Dozier, Richard Boyce, Bob Boyle, Scott Peterson, Alex C. Vo. Preclinical pharmacokinetics of CASC-578, a novel, selective, potent, and orally bioavailable small molecule checkpoint kinase 1 inhibitor [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4090. doi:10.1158/1538-7445.AM2017-4090
Abstract 4092: Targeting compensatory mechanisms of resistance to phosphatidylinositol 3-kinase inhibitors in head and neck squamous cell carcinoma
Authors: Michmerhuizen Nicole L. , Leonard Elizabeth , Foltin Susan K. , Kulkarni Aditi , Carey Thomas E. , Bradford Carol R. , Jiang Hui , Brenner Chad
Published: July 2017

Recent sequencing studies of head and neck squamous cell carcinomas (HNSCCs) have identified the phosphatidylinositol 3-kinase (PI3K) pathway as the most frequently mutated, oncogenic pathway in this cancer type. Despite the frequency of activating mutations or amplification in PIK3CA (the gene encoding the catalytic subunit of PI3K), targeted inhibitors of PI3K have not shown clinical efficacy as monotherapies. We tested a panel of more than 20 patient-derived oral cavity squamous cell carcinoma (OCSCC) cell lines, which were profiled by Nimblegen V3 exome sequencing, and observed resistance to PI3K inhibitors despite PIK3CA copy number amplification and/or mutation. Of six inhibitors tested, only alpha-isoform selective and pan-PI3K agents were somewhat effective; these inhibitors, despite on-target and downstream activity, did not cause an appreciable reduction in cell viability when administered at submicromolar concentrations. We hypothesized that other oncogenic pathways might still be functional in the presence of PI3K inhibitors and might serve as mediators of this resistance. For example, our group and others have evaluated co-dependence on the Ras-MEK-ERK pathway in OCSCC, showing that this serves as a compensatory mechanism in some models. In order to more fully characterize other novel mechanisms of resistance, we have also developed a high-throughput screening approach that utilizes a resazurin cell viability assay. This screen serves as an unbiased means of testing ~1400 inhibitors as monotherapies and in combination with alpha-isoform selective PI3K inhibitor HS-173 and pan-PI3K inhibitor BKM120 in several OCSCC models. Further validation of “hits” from this screen, which are drugs that are effective in combination but not as monotherapies, may identify additional resistance mechanisms and lead to combination therapies to improve HNSCC patient prognosis.

Citation Format: Nicole L. Michmerhuizen, Elizabeth Leonard, Susan K. Foltin, Aditi Kulkarni, Thomas E. Carey, Carol R. Bradford, Hui Jiang, Chad Brenner. Targeting compensatory mechanisms of resistance to phosphatidylinositol 3-kinase inhibitors in head and neck squamous cell carcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4092. doi:10.1158/1538-7445.AM2017-4092
Abstract 4103: IL-6 dynamics regulate neuroendocrine transformation in gefitinib acquired resistance EGFR mutant lung cancer cells
Authors: Wu Shang-Yin , Yeh Hsuan-Heng , Hung Chun-Hua , Lin Chien-Chung , Su Wen-Pin , Su Wu-Chou
Published: July 2017

Transformation to small-cell lung cancer (SCLC, one of aggressive neuroendocrine [NE] tumor) is reported when activating epidermal growth factor receptor (EGFR) mutant non-small-cell lung cancer acquired resistance to tyrosine kinase inhibitors (TKI, such as gefitinib). IL-6 activation confers to acquire TKI resistance and associates with p53 and RB inactivation those are SCLC hallmark changes. Whether NE transformation could phenocopy in isogenic acquired resistance cell line and the role of IL-6 in this process remain unknown. We established 827GRs (including 827GR, 827GR+ and 827GR.M6) acquired resistance to gefitinib from HCC827 cells by long term stepwise treated with gefitinib and they still had EGFR exon 19 deletion without acquired T790M. 827GR was parental resistance line with unstable gefitinib resistance in drug-free medium by passage. We maintained 827GR in medium with or without 1μM gefitinib over 6 months to generate stable clones: 827GR+ and 827GR.M6. 827GRs had SCLC hallmark changes, i.e., inactivation of p53, RB and Notch by western blot and gene set enrichment analysis. Compared to HCC827, 827GRs were more sensitive to cisplatin and etoposide but not paclitaxel. IL-6 level was positive correlated with gefitinib resistance among 827GRs by cytokine array and ELISA. Interestingly, among 827GRs, 827GR.M6 harbored low IL-6 secretion had obviously NOTCH-ASCL1-DLL3 alteration, high NE marker expression and significant inter-rater agreement with selected Byers’ SCLC gene signature than high IL-6 secretion 827GR+, suggesting IL-6 dynamics might regulate NE marker expression. IL-6 genetic manipulation in HCC827 and 827GR+ also demonstrated this phenomenon. Moreover, IL-6 dynamics correlate with NE expression also showed in patient derived lung cancer cell line in published microarray dataset (GSE64322). In conclusion, our work demonstrated activating EGFR mutant lung cancer acquired resistance to TKI with NE transformation could phenocopy in isogenic cell line model and IL-6 dynamics might regulate this process.

Citation Format: Shang-Yin Wu, Hsuan-Heng Yeh, Chun-Hua Hung, Chien-Chung Lin, Wen-Pin Su, Wu-Chou Su. IL-6 dynamics regulate neuroendocrine transformation in gefitinib acquired resistance EGFR mutant lung cancer cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4103. doi:10.1158/1538-7445.AM2017-4103
Abstract 4104: Intrinsic and acquired resistance to cetuximab in colorectal cancer patients
Authors: Bray Steven M. , Lee Jeeyun , Kim Seung Tae , Ebert Philip J. , Calley John N. , Wulur Isabella H. , Gopalappa Thejaswini , Wong Swee Seong , Qian Hui-Rong , Ting Jason C. , Liu Jiangang , Willard Melinda D. , Aggarwal Amit , Novosiadly Ruslan D. , Kim Hee-Cheol , Reinhard Christoph
Published: July 2017

Anti-EGFR antibodies, such as cetuximab, are effective therapies for many late-stage colorectal cancer (CRC) patients; unfortunately, many tumors are initially unresponsive while others show initial efficacy but eventually develop acquired resistance. Genomic studies of patient tumors, cell lines, and xenograft models have identified putative anti-EGFR resistance markers, including mutations in KRAS, NRAS, BRAF, PIK3CA, and the EGFR extracellular domain, as well as amplifications in ERBB2 and MET. In order to further confirm and identify new resistance mechanisms to anti-EGFR treatment in CRC, we performed retrospective genomic profiling of 25 CRC patients treated at Samsung Medical Center from 2006-2015. Patients received cetuximab containing chemo regimens with varying duration of responses, including acquired resistance cases. Our analysis identifies mutations in receptor tyrosine kinases, such as EGFR, NTRK1, and PDGFRA, as well as RAS/MAPK pathway genes that affect cetuximab response. We also uncover genomic alterations in ERBB2 and c-KIT as potential novel mechanisms regulating sensitivity to anti-EGFR antibodies. Additional genomic analyses of acquired resistance tumors and in vitro studies of a patient-derived cell line provide added insights into clonal selection and signaling pathways that bypass the EGFR blockade. Overall, our study elucidates important new facets in the landscape of anti-EGFR resistance mechanisms.

Note: This abstract was not presented at the meeting.

Citation Format: Steven M. Bray, Jeeyun Lee, Seung Tae Kim, Philip J. Ebert, John N. Calley, Isabella H. Wulur, Thejaswini Gopalappa, Swee Seong Wong, Hui-Rong Qian, Jason C. Ting, Jiangang Liu, Melinda D. Willard, Amit Aggarwal, Ruslan D. Novosiadly, Hee-Cheol Kim, Christoph Reinhard. Intrinsic and acquired resistance to cetuximab in colorectal cancer patients [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4104. doi:10.1158/1538-7445.AM2017-4104
Abstract 411: In vivo pooled shRNA library identifies KPNB1 as a new drug target for epithelial ovarian cancer
Authors: Kodama Michiko , Kodama Takahiro , Yoshihara Kosuke , Hashimoto Kae , Mabuchi Seiji , Sawada Kenjiro , Kimura Tadashi , Copeland Neal , Jenkins Nancy
Published: July 2017

Objective

Epithelial ovarian cancer (EOC) is a most lethal cancer in gynecology, of which cure rate is 30%. To seek its new therapeutic targets, we performed in vivo loss of function screen.

Method

Human EOC cell line, SKOV3, was transduced with pooled druggable shRNA library containing 42450 shRNAs targeting 7490 genes. Transduced cells were intraperitoneally injected into 12 female nude mice and monitored for PC tumor formation. Genomic DNA of 12 biggest PC tumors were sequenced to identify shRNAs depleted in these tumors.

Results

Ten potential drug targets were identified, including 2 known oncogenes, ERBB2 and RAF1. Second highest ranked gene, KPNB1, is known as a nuclear transporter. KPNB1 inhibition significantly decreased and overexpression increased in vitro cell proliferation in multiple EOC cell lines. KPNB1 inhibition caused multi-phase cell cycle delay at both of G1/S and G2/M transition via elevation of p21 and p27 and induced apoptosis. KPNB1 inhibition significantly decreased in vivo tumor formation through the same mechanism as in vitro, because more cleaved PARP and less Ki67 positive cells were found in KPNB1 knockdown tumors via immunochemical staining. We found a positive correlation between KPNB1 mRNA levels and poor survival of EOC patients, suggesting the oncogenic role of KPNB1 in human EOC. Comprehensive mass spectrometric study identified that KPNB1 positively regulated several members of anaphase promoting complex/cyclosome. Lastly, we found that ivermectin, a well-known anti-parasitic drug, exerted an anti-proliferative effect on EOC cell lines via KPNB1 inhibition, and its combination with paclitaxel synergistically suppressed cell proliferation in vitro and inhibited tumor formation in vivo.

Conclusion

In vivo pooled shRNA library screen identified KPNB1 as a new drug target for EOC. Ivermectin can be a new therapeutics for EOC especially combined with paclitaxel.

Citation Format: Michiko Kodama, Takahiro Kodama, Kosuke Yoshihara, Kae Hashimoto, Seiji Mabuchi, Kenjiro Sawada, Tadashi Kimura, Neal Copeland, Nancy Jenkins. In vivo pooled shRNA library identifies KPNB1 as a new drug target for epithelial ovarian cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 411. doi:10.1158/1538-7445.AM2017-411
Abstract 4110: Combinatory approaches targeting EGFR, HER2 and c-MET in recurrent SCCHN
Authors: Wang Dongsheng , Magliocca Kelly R. , Nannapaneni Sreenivas , Steuer Coner , Patel Mihir R. , El-Deiry Mark W. , Wang Xu , Chen Zhengjia , Shin Dong M. , Saba Nabil F. , Chen Zhuo G.
Published: July 2017

Squamous cell carcinoma of the head and neck (SCCHN) cells that escape cetuximab inhibition exhibit HER2, HER3, and/or c-Met activation. Simultaneous inhibition of EGFR, HER2, HER3 and c-Met presents an attractive clinical strategy for treating SCCHN that has progresses despite EGFR-targeted therapy. In an effort to develop new combination drug therapy options for recurrent SCCHN, we evaluated three different c-Met inhibitors in combination with a pan-HER inhibitor (afatinib/crizotinib, afatinib/tivantinib, afatinib/cabozantinib) and investigated their anti-tumoral effects. SCCHN cell lines (JHU022 highly expresses c-Met, and SCC1-C is cetuximab resistant) as well as patient derived xenograft (PDX) animal models from patients with recurrent SCCHN were investigated. In our cell line study, western-blot assay indicated that activation of EGFR, HER2, and c-Met was blocked in all three combinations. In addition the downstream PI3K/AKT and ERK signaling pathways were inhibited. Sulforhodamin B colorimetric assay (SRB) revealed SCCHN cell growth was more effectively inhibited by the combinations compared to any of the single inhibitors in vitro. Furthermore, the combination was more potent in inducing apoptosis when compared to each of the single treatments. Finally in the PDX study, all treatment groups had significantly greater efficacy compared to the non-treated control group (p<0.005) and all combination treatments exhibited better efficacy in tumor growth inhibition than their respective single inhibitors (p<0.0l). In conclusion, our study demonstrates that targeting EGFR, HER2, and c-Met with combination of their inhibitors is more effective than each of the single inhibitors alone both in vitro and in SCCHN PDX models. This study paves the way for further clinical investigation of this combination in patients with SCCHN who have progressed after cetuximab-based therapy. (This study is supported by NIH/NCI R21 CA182662-01A1 to NFS and ZGC)

Citation Format: Dongsheng Wang, Kelly R. Magliocca, Sreenivas Nannapaneni, Coner Steuer, Mihir R. Patel, Mark W. El-Deiry, Xu Wang, Zhengjia Chen, Dong M. Shin, Nabil F. Saba, Zhuo G. Chen. Combinatory approaches targeting EGFR, HER2 and c-MET in recurrent SCCHN [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4110. doi:10.1158/1538-7445.AM2017-4110
Abstract 4116: Acquired lapatinib resistant induces EMT-phenotype in breast cancer cells via Src and RUNX3
Authors: Kim So Hyeon , Min Ahrum , Kim Seongyeong , Ha Dong Hyeon , Jang Hyemin , Kim Yu Jin , Lee Kyung-Hun , Kim Tae-Yong , Im Seock-Ah
Published: July 2017

Background: Lapatinib is an effective EGFR and HER2 targeting small molecular tyrosine kinase inhibitor which is widely used for HER2 positive breast cancer patients. However, patients eventually acquire resistance, limiting its long-term use. Overexpression of heregulin, a HER3 ligand, acquired stemness were mechanism that confers resistance to the anti-HER2 lapatinib. However, still, unknown mechanisms of developing lapatinib resistant remain as a question to solve. Thus, we tried to find out there is a novel mechanism which related to lapatinib resistant, and any specified molecules were involved in this process.

Methods: Acquired resistant SK-BR-3 cells were established by chronic exposure to lapatinib or trastuzumab. Lapatinib or trastuzumab sensitivity were confirmed by MTT assay. Western blotting was used to determine signal transduction molecule changes. Wound healing assay and Boyden chamber assay were conducted for verifying invasive ability. Whole exome sequencing (WES) and siRNA knock-down system were used for further analysis.

Results: Lapatinib resistant (LR) cell lines showed down-regulation of p-HER2, p-Akt, and p-Erk. The activity of Src family kinase was increased in LR cells. Vimentin, famous EMT marker, is also increased in LR cells. Migration and invasion were significantly increased in LR cells. Correlated with a missense mutation of RUNX3, which identified by WES, expression of RUNX3 was decreased in LR cells. Moreover, siRNA knock-down parental cells showed more resistance to lapatinib.

Conclusion: The increase of Src activation, cell migration, and invasion was observed in LR cells. RUNX3, which identified by WES, affected to lapatinib sensitivity in SK-BR-3 cells. Therefore, RUNX3 might be a specified molecule, which partially contributes resistance to lapatinib.

Citation Format: So Hyeon Kim, Ahrum Min, Seongyeong Kim, Dong Hyeon Ha, Hyemin Jang, Yu Jin Kim, Kyung-Hun Lee, Tae-Yong Kim, Seock-Ah Im. Acquired lapatinib resistant induces EMT-phenotype in breast cancer cells via Src and RUNX3 [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4116. doi:10.1158/1538-7445.AM2017-4116
Abstract 4126: Validation of hypoglycosylated MUC1-CIN85 protein-protein interaction as a new therapeutic target for prevention of cancer invasion and metastasis
Authors: Cascio Sandra , Faylo Jacque , Sriram Raahul , Vlad Anda , Camacho Carlos , Finn Olivera J.
Published: July 2017

Overexpression and abnormal glycosylation of the epithelial glycoprotein MUC1 in cancer cells promotes metastasis. We have identified CIN85 (Cbl-interacting protein 85 KDa), as a binding partner of MUC1 in tumors. MUC1/CIN85 complex is found in early as well as advanced clinical stages of breast, ovarian, colon and prostate cancers among others. Co-localization of MUC1 and CIN85 on invadopodia structures enhances invasion and migration of cancer cells. Our hypothesis is that preventing the formation or dissociating existing CIN85/MUC1 complexes may result in a less aggressive tumor by decreasing local invasion and preventing distant metastases. To test this hypothesis, we have already identified and tested two novel compounds that significantly reduce the association between hypoglycosylated form of MUC1 and CIN85, and at 10μM concentration drastically reduce the migratory activity of mouse and human epithelial cancer cells. Our preliminary data also suggest that dissociation of the MUC1 and CIN85 complex decreases expression of hypoglycosylated MUC1, restoring the expression of its normal, fully glycosylated form. We are currently investigating the MUC1/CIN85-dependent signaling pathway with a particular focus on the ability of CIN85 to modulate MUC1 glycosylation by controlling its plasma membrane-Golgi trafficking. Ongoing experiments in an in vivo mouse model will confirm the ability of these drug compounds to decrease tumor growth and metastasis and validate CIN85/MUC1 complex as a viable therapeutic target and support development and testing of more potent antagonists.

Citation Format: Sandra Cascio, Jacque Faylo, Raahul Sriram, Anda Vlad, Carlos Camacho, Olivera J. Finn. Validation of hypoglycosylated MUC1-CIN85 protein-protein interaction as a new therapeutic target for prevention of cancer invasion and metastasis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4126. doi:10.1158/1538-7445.AM2017-4126
Abstract 4130: Characterization of URST1 as a prognostic biomarker and therapeutic target for lung cancer
Authors: Takano Atsushi , Miyagi Yohei , Daigo Yataro
Published: July 2017

Lung cancer is the most frequent cause of cancer deaths worldwide and its overall prognosis remains poor. Therefore, next generation of biomarkers and therapeutic strategies for lung cancer are eagerly awaited. We selected genes that were overexpressed in the majority of lung cancer using our gene expression profile database. During this process, we identified URST1 (Up-regulated in solid tumor 1) as a candidate. Immunohistochemical staining showed that URST1 expression was observed in the majority of non-small cell lung cancer (NSCLC) patients (P = 0.0013 by log rank test). Multivariate analysis revealed high level of URST1 expression was an independent prognostic factor for NSCLC patients. Moreover, reduction of URST1 by siRNA or treatment with URST1 inhibitor significantly suppressed lung cancer cell growth probably through cell cycle arrest at G2/M. Exposure of cancer cells to URST1 inhibitor significantly suppressed These data suggest that URST1 is a possible prognostic biomarker and therapeutic target for lung cancer.

Citation Format: Atsushi Takano, Yohei Miyagi, Yataro Daigo. Characterization of URST1 as a prognostic biomarker and therapeutic target for lung cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4130. doi:10.1158/1538-7445.AM2017-4130
Abstract 4136: Effect of prorenin receptor PRR knock down and telmisartan on endometrial cancer growth
Authors: Mohammed Riazuddin , Delforce Sarah J. , Wang Yu , Verrills Nicole M. , Lumbers Eugenie R. , Pringle Kirsty G.
Published: July 2017

Endometrial cancer is the most common gynaecological malignancy and its incidence is increasing. Tissue renin angiotensin systems (RAS) are known to stimulate angiogenesis, cell proliferation and migration. All of these actions potentiate cancer growth and spread. We have previously demonstrated that endometrioid endometrial cancers express both prorenin and prorenin receptor ((P)RR) mRNA and have significantly greater levels of these proteins than normal adjacent endometrial tissue. Prorenin acting via the (P)RR can activate both RAS dependent and independent signalling pathways. Therefore we hypothesized that endometrial cancer growth can be inhibited by drugs that block Ang II/AT1R interactions and prorenin/(P)RR mediated signaling pathways. To determine the functional role of (P)RR in endometrial cancer growth, we used siRNA transfection to knock down (P)RR expression in three endometrial cancer cell lines (Ishikawa, HEC-1A and AN3CA) at 24h, 48h, 72h & 96h. The effect of RAS blockers on cell viability was also assessed by Resazurin assay at 48h in the three endometrial cancer cell lines.

All three of the endometrial cancer cell lines examined (Ishikawa, HEC-1A and AN3CA) expressed (P)RR and prorenin mRNA, however levels of (P)RR were much higher in Ishikawa cells. Transfection of the three cell lines with a (P)RR siRNA resulted in 90% knockdown of (P)RR mRNA expression and reduced the cell viability of both Ishikawa and AN3CA but not HEC-1A cells, as measured by a resazurin assay after 48h incubation. Aliskiren (a renin inhibitor) inhibited Ishikawa cell growth by 20%. There was no effect of Aliskiren on cell viability in HEC-1A and AN3CA cell lines. Perindoprilat (an ACE inhibitor) and Losartan (an angiotensin II type 1 receptor (AT1R) inhibitor) had no effect on cell viability in any cell line. Another AT1R antagonist, telmisartan, which also acts as a selective agonist of peroxisome proliferator-activated receptor gamma (PPAR-γ), did however significantly reduce cell viability in all cell lines (Ishikawa 75%, HEC-1A 50% and AN3CA 60%).

Removal of the prorenin receptor inhibits the growth and development of some endometrial cancer cell lines. Only telmisartan, which has properties additional to Ang II antagonism, was effective in inhibiting endometrial cancer cell growth. (P)RR knockdown and telmisartan are therefore potential therapeutic drugs for the treatment of endometrial cancer.

Citation Format: Riazuddin Mohammed, Sarah J. Delforce, Yu Wang, Nicole M. Verrills, Eugenie R. Lumbers, Kirsty G. Pringle. Effect of prorenin receptor PRR knock down and telmisartan on endometrial cancer growth [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4136. doi:10.1158/1538-7445.AM2017-4136
Abstract 4140: Identification of a selective MKLP2/KIF20A inhibitor with high in-vivo antitumor activity
Authors: Collette Yves , Miserey-Lenkei Stephanie , Guillou Catherine , Carniato Denis , Pau Bernard , Goud Bruno , Vey Norbert , Bougeret Cecile E.
Published: July 2017

Mitotic kinesins are essential regulators of cancer cell replication and migration. The mitotic kinesin MKLP2/KIF20A, a member of the kinesin-6 family, plays an essential role during cytokinesis and was identified as a potential new target for cancer chemotherapy1. We have previously identified Paprotrain, a new synthetic compound, as the first selective MKLP2 inhibitor2. Recently, we obtained Paprotrain analogues with higher potency on MKLP23. Herein we describe the identification and characterization of BKS0349, a new potent analogue of Paprotrain.

BKS0349 compound is 10 times more potent than paprotain on MKLP2 inhibition and has shown an even more restricted specificity profile when tested on a large set of kinases. In-vitro this compound is highly cytotoxic on a wide panel of human cancer cell lines (IC50 ranged 10-70 nM, which corresponds to 1000 fold improvement of paprotrain potency) while no toxicity is observed on human normal cells such as peripheral blood mononuclear cells (PBMC) and primary hepatocytes (IC50 >50µM). BKS0349 compound is well tolerated in mice using repeated intravenous administrations (200 mg/kg, twice a week for 4 weeks). In xenografted nude mice, in-vivo treatment with BKS0349 compound demonstrates a high antitumor activity against various human cancer cell models, either sensitive or resistant to some standard-of-care treatments. In addition, human cancer cells treated in-vitro as well as in-vivo with BSK0349 compound display Golgi scattering and a mitotic arrest leading to cell death, as hallmarks of BKS0349’ mode of action.

These findings show that MKLP2 is a potential new target for cancer chemotherapy and BKS0349 a good candidate to be developed for cancer treatment.

1Paclitaxel targets FOXM1 to regulate KIF20A in mitotic catastrophe and breast cancer paclitaxel resistance. P. Khongkow et al. Oncogene, 2015, 1-13.

2Relocation of Aurora B and Survivin from centromeres to the central spindle impaired by a kinesin-specific MKLP-2 inhibitor. S. Tcherniuk et al. Angew. Chem. Int. Ed., 2010, 49:8228-8231.

3New MKLP-2 inhibitors in the paprotrain series: design, synthesis and biological evaluations. C. Labrière et al. Bioorg and Med Chem, 2016, 24:731-734.

Note: This abstract was not presented at the meeting.

Citation Format: Yves Collette, Stephanie Miserey-Lenkei, Catherine Guillou, Denis Carniato, Bernard Pau, Bruno Goud, Norbert Vey, Cecile E. Bougeret. Identification of a selective MKLP2/KIF20A inhibitor with high in-vivo antitumor activity [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4140. doi:10.1158/1538-7445.AM2017-4140
Abstract 4155: Crosstalk of SOX2 and epithelial-to-mesenchymal transition on EGFR-TKI resistance
Authors: Lee An-Chun , Chiu Yu-Fan , Kuo Ming-Han , Wang Yuan-Hung , Chou Yu-Ting
Published: July 2017

EGFR-tyrosine kinase inhibitors (TKIs) have been shown to produce profound therapeutic responses in lung adenocarcinoma harboring EGFR mutations. Despite this initial response, patients with EGFR-mutated lung adenocarcinoma ultimately developed resistance to EGFR-TKIs. Although both SOX2 and epithelial-to-mesenchymal (EMT) have been linked to the EGFR-TKI resistance in lung adenocarcinoma, the interplay between SOX2 and EMT in EGFR-TKI resistance is not known. Here, we report that cancer plasticity switched by SOX2 and EMT regulates EGFR-TKI resistance. We found that the selection of EGFR-TKI resistant cells induced EMT while attenuating SOX2 expression. We observed that EGFR-TKI treatment induced SOX2 expression in EGFR-mutated lung cancer cells, and SOX2 silencing encouraged EGFR-TKI resistance. Preselection of EGFR-mutated lung cancer cells with the EMT feature endowed cells with EGFR-TKI resistance but suppressed SOX2 expression. We found that TGF-β induced EMT but attenuated SOX2 expression, resulting in increased EGFR-TKI resistance. Pharmacological inhibition of HDACs in EGFR-mutated cells attenuated SOX2 expression but induced EMT, causing increased EGFR-TKI resistance. Enriching SOX2 expression in EGFR-mutated cells attenuated EMT and rendered cells more sensitive to EGFR-TKIs. Correlation analysis exhibited negative correlations between SOX2 and EMT markers in primary non-small cell lung cancer. Kaplan-Meier analysis revealed that a SOX2 low/Vimentin high signature predicted a poor survival in EGFR-mutated lung adenocarcinoma. Our findings support the notion that the cancer plasticity regulated by SOX2 and EMT plays a critical role in EGFR-TKI resistance, and SOX2 and Vimentin can function as prognostic biomarkers in lung cancer progression.

Citation Format: An-Chun Lee, Yu-Fan Chiu, Ming-Han Kuo, Yuan-Hung Wang, Yu-Ting Chou. Crosstalk of SOX2 and epithelial-to-mesenchymal transition on EGFR-TKI resistance [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4155. doi:10.1158/1538-7445.AM2017-4155
Abstract 4158: Targeting the imatinib-resistant BCR-ABL T315I mutation in chronic myeloid leukemia through a novel BCR-ABL inhibitor
Authors: Gupta Pranav , Kathawala Rishil , Wei Liuya , Wang Fang , Wang XiaoKun , Druker Brian J. , FU Li-Wu , Chen Zhe-Sheng
Published: July 2017

Chronic Myeloid Leukemia (CML), a hematological malignancy, is largely caused by the Philadelphia (Ph) chromosome carrying the Break point Cluster Region-Abelson (BCR-ABL) oncogene. Imatinib is a BCR-ABL-targeted therapy and considered the standard of care in CML management. Resistance to imatinib therapy often develops because of mutations in the BCR-ABL kinase domain. In this study, we evaluated PBA2, a novel BCR-ABL inhibitor, for its anti-cancer activity against BCR-ABL expressing BaF3 cells. PBA2 shows potent activity against wild-type and T315I mutated BaF3 cells as compared with imatinib. PBA2 inhibited the phosphorylation of BCR-ABL and its downstream signaling in BaF3/WT and BaF3/T315I cells. PBA2 inhibited the mRNA expression of BCR-ABL in BaF3/WT and BaF3/T315I cells. Mechanistically, PBA2 increased the cell population in sub G1 phase of the cell cycle, induced apoptosis and elevated ROS production in both BaF3/WT and BaF3/T315I cells. Taken together, our results indicate that PBA2 exhibits anti-proliferative effects and inhibits the imatinib-resistant T315I BCR-ABL mutation. PBA2 may be a novel drug candidate for overcoming the resistance to imatinib in CML patients.

Note: This abstract was not presented at the meeting.

Citation Format: Pranav Gupta, Rishil Kathawala, Liuya Wei, Fang Wang, XiaoKun Wang, Brian J. Druker, Li-Wu FU, Zhe-Sheng Chen. Targeting the imatinib-resistant BCR-ABL T315I mutation in chronic myeloid leukemia through a novel BCR-ABL inhibitor [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4158. doi:10.1158/1538-7445.AM2017-4158
Abstract 4159: In vitro drug response (IVDR) and tumor-associated biomarker (BM) expression profiles in lung carcinoma (LC)
Authors: Parker Ricardo J. , Schiltz Patric M. , Myers Michael P.
Published: July 2017

Assessing IVDR to Chemo and BM expression in tumors of patients (Pts) before treatment can stratify therapy and improve outcome. Historical IVDR and BM data were analyzed retrospectively on 582 human LC specimens including 311 adenocarcinomas (ADCA), 131 non-small cell lung carcinomas (NSCLC), and 140 squamous cell carcinomas (SQCC) resected from Pts diagnosed with primary (PD), recurrent (RD) or metastatic disease (MD), and tested at a single clinical reference lab between March 2004 and July 2006. Pt and specimen information were unlinked directly and anonymized. IVDR was determined in prepared aliquots of Pts’ viable tumor cell suspensions after 5-day exposures to single physiologic doses of Chemo (CARBO, CPLAT, GMCB, NVBL, TAXOL, TXTR, VP16, TOPO). IVDR was bifurcated into extreme resistance (ER, non-response) or low resistance (LR, response). Standard immunohistochemistry (IHC) was performed on the same Pts’ paraffin-embedded LC sections to detect BMs mutant-p53 (mp53; n=322), EGFR (n=250), and BCL-2 (n=270), and results showed 57% overexpressed mp53, 91% overexpressed EGFR, and 32% expressed BCL-2. IVDR profiles for ADAC and NSCLC were similar, while SQCC was comparatively less resistant. IVDR profiles for PD, RD and MD of a given histology were relatively dissimilar. In ADCA, RD was more resistant than PD and MD. In NSCLC and SQCC, MD was more resistant. Significant portions of LCs showed prevalent ER to CARBO, TAXOL, TXTR, and VP16; and cross resistance to combinations, suggesting no clinical benefit from toxic ineffective Chemo. In such settings, disease progression may negatively impact a Pt’s tolerance to further Chemo. Pre-assessment of IVDR and BMs may identify ER factors, stratify treatment, and potentially improve clinical outcomes.

Citation Format: Ricardo J. Parker, Patric M. Schiltz, Michael P. Myers. In vitro drug response (IVDR) and tumor-associated biomarker (BM) expression profiles in lung carcinoma (LC) [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4159. doi:10.1158/1538-7445.AM2017-4159