bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 2849: Axl: A promising therapeutic target that leads to multimodal inhibition of the metastatic pathway
Authors: Tanaka Mai , Siemann Dietmar W.
Published: August 2019

Cancer is the second leading cause of death in the United States and approximately 90% of cancer-related deaths result from metastasis, the spread of cancer cells to secondary sites. In tumors, the upregulation of certain signaling pathways promotes the metastatic phenotypes of cancer cells characterized by enhanced invasion, migration, survival, proliferation and induction of angiogenesis. A key pathway involved in metastasis is the receptor tyrosine kinase Axl. Axl is expressed in a variety of tumor types and is associated with poor prognosis, metastasis, and outcome. The purpose of the current study was to evaluate the efficacy of genetic and pharmacologic inhibitions of Axl on the metastatic phenotypes, specifically cell migration, invasion and angiogenesis.

Human breast and prostate cancer cell lines (MDA-MB-231 and PC3-ML, respectively), and human lung microvascular endothelial cell (HMVEC-L) were used in this study. Stable Axl short hairpin RNA (shRNA) knockdown MDA-MB-231 and PC3-ML cell lines were generated by Mission Lentiviral transduction particles (Sigma). The efficacy of genetic and pharmacologic inhibition of Axl on tumor cell migration and invasion was evaluated by transwell migration and invasion assays. The effect of Axl knockdown on prostate cancer cell metastasis in vivo was evaluated by an intracardiac bone metastasis model. Conditioned media of Axl knockdown or control MDA-MB-231 cells were analyzed for angiogenic factors using the human angiogenesis array. The effect of Axl knockdown conditioned medium on angiogenic properties in vitro were assessed by endothelial cell tube formation and sprouting. Induction of angiogenesis in vivo was measured by performing intradermal assay.

Genetic and pharmacologic inhibition of Axl decreases tumor cell migration and invasion. Axl knockdown inhibits metastatic disease burden of prostate cancer. Axl knockdown conditioned medium secretes less pro-angiogenic factors compared to its scramble control cells, suggesting that tumor cells utilize Axl pathway to promote the induction of angiogenesis. Axl knockdown conditioned medium impairs angiogenic properties, including endothelial cell tube formation and sprouting. Axl knockdown of tumor cells suppress tumor cell-induced angiogenesis in vivo. Collectively, these data indicate that Axl is involved in multiple steps of the metastatic pathway and that Axl is a promising anti-metastatic agent to inhibit tumor cell dissemination and initiation of angiogenesis. Further studies are ongoing to understand the downstream molecular signaling of Axl.

Citation Format: Mai Tanaka, Dietmar W. Siemann. Axl: A promising therapeutic target that leads to multimodal inhibition of the metastatic 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 2849.
Abstract 2852: PKM2 phosphorylates and stabilises Matrin 3 which promotes FOXC2-mediated tumorigenesis
Authors: Kumari Richa , Das Sanjeev
Published: August 2019

PKM2 is tumor specific isoform of Pyruvate kinase essential for Warburg effect. Apart from its well-known function in aerobic glycolysis, it has non-metabolic functions as well. Under oncogenic/mitogenic stimulation conditions it can translocate into the nucleus and acts as co-transactivator or kinase and promotes tumorigenesis. In order to explore its interactome we carried out a proteomic screen and found several interacting proteins. However, in vitro and in vivo studies confirmed Matrin 3 as a novel interacting partner of PKM2. Kinase assays revealed Matrin 3 as novel substrate of the PKM2-mediated phosphorylation. Further, we mapped the site of phosphorylation to the highly conserved T239 residue in Matrin 3. Intriguingly; this phosphorylation is inhibitory in nature as it prevents Matrin 3 degradation by abrogating K48-linked ubiquitylation. Moreover, the expression of a phospho-dead mutant of Matrin 3 or kinase-dead mutant of PKM2 increases ubiquitylation and leads to reduced level of Matrin 3.We also identified K132 as site of ubiquitylation which is conserved across species. Further, we screened a shRNA library targeting nuclear E3 ubiquitin ligases and identified FBXO11 as the cognate E3 ligase involved in this degradation. Matrin 3 is a RNA binding protein which mediates post-transcriptional regulation of various mRNAs. Further studies using qPCR array for EMT related genes and RNA immunoprecipitation assays established that Matrin 3 binds to FOXC2 and promotes post-transcriptional stability of FOXC2. FOXC2 is a transcription factor which regulates EMT, angiogenesis, invasion/migration by regulating Integrin β-3, ZEB1 and c-MET. Decreased Matrin 3 level leads to reduced proliferation capacity, migration and invasiveness of tumor cells. Furthermore, mouse tumor models confirmed that Matrin 3 promotes tumorigenesis, metastasis and invasion in FOXC2 dependent manner. Taken together, our findings add to the substrate repertoire of nuclear PKM2 kinase and provide key insights into FOXC2-mediated tumorigenesis.

Citation Format: Richa Kumari, Sanjeev Das. PKM2 phosphorylates and stabilises Matrin 3 which promotes FOXC2-mediated tumorigenesis [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 2852.
Abstract 287: A novel class III receptor tyrosine kinase inhibitor synergizes with olaparib by inhibition of DNA repair-related genes in non-small cell lung cancer cells
Authors: Ryu Hwani , Song Jie-young , Hwang Sang-Gu , Ahn Jiyeon
Published: August 2019

The platelet-derived growth factor receptors (PDGFRs), which are classified with class III receptor tyrosine kinase (RTK) family, play critical roles in cell proliferation, differentiation, and malignancy in various types of human cancers. To develop novel class III RTK inhibitors, dozen novel oxazole amine derivatives were designed and synthesized. Among the synthesized compounds, KM201 showed inhibitory activities of pan-class III RTK by an in vitro kinase activity assay and potent anti-proliferative activities in variety of cancer cell lines including leukemia and solid cancer cells. Genome-wide RNAseq profiling revealed a significant decrease of DNA repair-related genes in non-small cell lung cancer A549 cells treated with KM201. Moreover, KM201-induced DNA damage was detected by H2AX phosphorylation, which led to cell cycle arrest in the G2/M phase. We hypothesized that KM201 in combination with a PARP inhibitor may exhibit synergistic effect on inhibition of proliferation since PARP inhibitors are primarily effective against cancers with loss-of-function mutations in BRCA1 and BRCA2. Combination of KM201 and olaparib (a PARP inhibitor) markedly more effective in anti-proliferation and apoptotic cell death in A549 and H1299 cells harboring wild type BRCA1/2, compared with either drug alone. Our results show that the novel class III RTK inhibitor KM201 inhibits proliferation of leukemia and solid tumor cells by potentiating DNA damage and exerts synergistic cytotoxicity in combination with olaparib. Further detailed studies could help to investigate the full potential of KM201 as a class III RTK inhibitor and a combination adjuvant of PARP inhibitors.

Citation Format: Hwani Ryu, Jie-young Song, Sang-Gu Hwang, Jiyeon Ahn. A novel class III receptor tyrosine kinase inhibitor synergizes with olaparib by inhibition of DNA repair-related genes in non-small cell lung cancer cells [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 287.
Abstract 2870: Genetic mechanisms of primary chemotherapy resistance in pediatric acute myeloid leukemia
Authors: McNeer Nicole , Philip John , Geiger Heather , Ries Rhonda E. , Lavallee Vincent-Philippe , Walsh Michael , Shah Minita , Arora Kanika , Emde Anne-Katrin , Robine Nicolas , Alonzo Todd A. , Kolb E. Anders , Gamis Alan S. , Smith Malcom , Gerhard Daniela Se , Guidry-Auvil Jaime , Meshinchi Soheil , Kentsis Alex
Published: August 2019

Survival for children with acute myeloid leukemia (AML) remains low, with a primary induction remission failure rate of 10-15%. Although some mutations have been identified that are associated with increased relapse risk, the genomic landscape of pediatric AML resistant to primary chemotherapy is not well characterized. As part of the TARGET initiative (Therapeutically Applicable Research To Generate Effective Treatments), we assembled a cohort of 28 pediatric AML patients with primary chemotherapy resistance and failure of induction chemotherapy, uniformly treated as part of the COG AAML0531 study. We analyzed whole-genome DNA, mRNA, and miRNA sequence data obtained at diagnosis and after induction chemotherapy. At least three genetically distinct groups were apparent in this cohort, including those with NUP98 rearrangements, somatic mutations of WT1 in the absence of NUP98 variants, and additional recurrent variants including those in KMT2C and MLLT10. Comparisons of mutations before and after chemotherapy revealed both common and distinct gene expression programs. On chemotherapy exposure, these leukemias exhibited diverse forms of clonal evolution. We observed selection for mutant alleles of FRMD8, DHX32, PIK3R1, SHANK3, MKLN1, as well as persistence of WT1 and TP53 mutant clones, and elimination or contraction of FLT3, PTPN11, and NRAS mutant clones. These findings suggest diverse genetic mechanisms for primary chemotherapy resistance in pediatric AML, which should guide new approaches for its diagnosis and therapy.

Citation Format: Nicole McNeer, John Philip, Heather Geiger, Rhonda E. Ries, Vincent-Philippe Lavallee, Michael Walsh, Minita Shah, Kanika Arora, Anne-Katrin Emde, Nicolas Robine, Todd A. Alonzo, E. Anders Kolb, Alan S. Gamis, Malcom Smith, Daniela Se Gerhard, Jaime Guidry-Auvil, Soheil Meshinchi, Alex Kentsis. Genetic mechanisms of primary chemotherapy resistance in pediatric acute myeloid leukemia [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 2870.
Abstract 2892: Genetic inhibition of STAT3 increases medulloblastoma chemosensitivity
Authors: Ray Sutapa , Coulter Donald , Wilder Phillip , Sughroue Jason , Chaturvedi Nagendra , Mcguire Timothy , Joshi Santharam , Sharp Graham , Bhakat Kishor , Rizzino Angie
Published: August 2019

Medulloblastoma (MB) is the most common malignant brain tumor in children that arises from cerebellar neuronal progenitor cells. Post-surgical radiotherapy in combination with adjuvant chemotherapy are considered as standard treatment of care for MB. However, this long-term treatment often leads to harmful neurologic effects to the developing brain in children. Therefore, identification of novel therapeutic target to increase efficacy and reduce toxicity in MB represent an unmet clinical need. Signal transducers and activators of transcription-3 (STAT3) is constitutively activated in MB, where it functions as an oncoprotein, mediating cancer cell proliferation. Here, to evaluate the biological consequences of specific targeting of STAT3 in detail, we engineered MYC expressing Group 3 MB cells to stably express STAT3 shRNA under a doxycycline (Dox) inducible promoter and assessed the its effect on STAT3 function. Treatment of MB cells with Dox leads to growth inhibition and cell cycle arrest. Dox treatment downregulated expression of STAT3 and its target genes/proteins including MYC and delayed migration of MB cells. Expression of STAT3 shRNA decreased association of STAT3, BRD4, phospho-RNA Pol II to the proximal promoter of MYC and CCND1. It further downregulated occupancy of acetylated histone H3 K27 to the MYC and CCND1 promoter indicating gene repression. Moreover, we showed that combination Dox and cisplatin significantly decreased highly aggressive MYC-amplified MB cell growth and induced apoptosis by downregulating STAT3 regulated proliferation and anti-apoptotic gene expression. Together, our results revealed an important role of STAT3 in regulating MB pathogenesis. Disruption of this pathway with STAT3 inhibitor, therefore, may serves as a promising candidate for targeted MB therapy by enhancing chemo-sensitivity of MB cells, potentially improving outcomes in high-risk patients.

Citation Format: Sutapa Ray, Donald Coulter, Phillip Wilder, Jason Sughroue, Nagendra Chaturvedi, Timothy Mcguire, Santharam Joshi, Graham Sharp, Kishor Bhakat, Angie Rizzino. Genetic inhibition of STAT3 increases medulloblastoma chemosensitivity [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 2892.
Abstract 2893: ALK amplification and rearrangements are recurrent targetable events in glioblastoma
Authors: Blandin Anne-Florence
Published: August 2019

Anaplastic Lymphoma Kinase (ALK) expression, rearrangements, and single nucleotide variants have been reported in several brain tumor types, but the significance and function of each aberration in adults and children have not been clearly established. To determine the degree to which ALK represents a relevant therapeutic target in gliomas, we first examined ALK expression using immunohistochemistry (IHC) in a panel of 148 adult GBM and 49 pediatric GBM/high grade gliomas. We identified high ALK expression was most frequent in pediatric gliomas (32%, 16/49, IHC score 2+ or 3+). Copy arrays/sequencing and FISH for the ALK locus revealed high levelALK amplification in 31% of ALK-expressing cases (5/16) but was a rare event in gliomas overall. Whole-genome sequencing and RNA sequencing identified novel and recurrent PPP1CB-ALKfusions in 43% of ALK-expressing pediatric GBM (7/16), suggesting IHC may be an efficient means of screening for ALK aberrations as in the identification of EML4-ALK lung cancer. All ALK- amplified cases harbored PPP1CB-ALK fusion but 2 PPP1CB-ALK cases were copy neutral. The phosphatase PPP1CB was fused in-frame to ALK at exon 20 with preservation of the ALK kinase domain and predicted to activate via the same mechanism as other ALK rearranged cancers. ALKfusion proteins promoted cell proliferation and constitutive kinase activity and upregulated STAT and AKT signaling pathways. However, expression of novel ALK missense mutations in NSCs did not promote proliferation. Administration of ALK inhibitor Crizotinib reduced tumor growth in a PDX GBM from a patient with a novel ALK fusion. This work validates amplification and rearrangement of ALK as a highly recurrent driver event and therapeutic target in GBM, particularly in young children where it may be the sole driver event.

Note: This abstract was not presented at the meeting.

Citation Format: Anne-Florence Blandin. ALK amplification and rearrangements are recurrent targetable events in glioblastoma [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 2893.
Abstract 290: Formulation of tolerable protocols for combination regimens to control triple-negative breast cancer cell-derived xenograft tumor development in animals
Authors: Pattarawat Pawat , Wallace Shelby , Odoi Agricola , Pfisterer Bianca , Wang Hwa-Chain R.
Published: August 2019

Cumulative research and clinical results suggest an advantage to use a multiple drug combination over a single drug to control tumor growth and metastasis. In general, combination therapy may result in lower treatment failure rates, lower case fatality ratios, slower development of resistance, and fewer side effects than monotherapy, as well as reducing cost. Triple-negative breast cancer (TNBC) is aggressive, lethal, and heterogeneous. The molecular heterogeneity may account for the differential responses of TNBC to chemotherapies. TNBC is sensitive to conventional chemotherapies with initially high response rates; however, the prognosis is not optimal due to cancer recurrence and metastasis. Although recent advancements in drug development of targeted therapeutics and immunotherapy were somewhat effective in treating TNBC, these therapeutics still need extensive study. Although combination regimens are thought to have better therapeutic outcomes than single drug treatments, drug combinations may also come with overlapped toxicities. Thus, it is important to identify combination regimens that are safe and effectively treat cancers. Based on our in vitro results of combination regiments effective in the synergistic induction of TNBC cell death, we systemically investigated the toxicity and efficacy of combined triple and double agents at various doses and administration protocols to assess the treatment of mice bearing TNBC cell-derived xenograft tumors. We analyzed the adverse effects of combination regimens on the bone marrows, livers, and kidneys, as well as the blood cell profiles in immune-competent and -deficient mice. Our studies successfully identified tolerable protocols for triple and double combination regimens of gemcitabine, romidepsin, and cisplatin, which are FDA-approved anticancer agents, as well as the efficacy of these combination regimens in controlling TNBC xenograft tumors in immune-deficient mice. Our results indicated that the triple combination of gemcitabine plus romidepsin and cisplatin regimen was more effective than double combination regimens in the control of TNBC tumor development in vivo. In conclusion, our studies suggested that the triple combination regimens should be promptly considered as an advanced treatment of TNBC over the conventional gemcitabine and cisplatin regimen or the clinical trial romidepsin plus cisplatin regimen.

Citation Format: Pawat Pattarawat, Shelby Wallace, Agricola Odoi, Bianca Pfisterer, Hwa-Chain R. Wang. Formulation of tolerable protocols for combination regimens to control triple-negative breast cancer cell-derived xenograft tumor development in animals [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 290.
Abstract 2904: Intratumor δ-catenin heterogeneity driven by genomic rearrangement dictates growth factor dependent prostate cancer cell fate and behavior
Authors: Li Mingchuan , Nopparat Jongdee , Zhang Jiao , Aguilar Byron J. , Chen Yan-Hua , Du Jie , Ai Xin , Luo Yong , Jiang Yongguang , Boykin Christi , Lu Qun
Published: August 2019

Only a small number of genes are bona fide oncogenes and tumor suppressors such as Ras, Myc, p53 and PTEN. However, targeting these cancer drivers frequently fail to demonstrate sustained cancer remission. Tumor heterogeneity and evolution contribute to cancer resistance and pose challenges for cancer therapy due to differential gene expression profiles driving distinct tumor responses to treatments. Here we report that intratumor heterogeneity of Wnt/β-catenin/armadillo modulator δ-catenin controls individual cell behavior to promote cancer. The differential intratumor subcellular localization of δ-catenin mirrors its compartmentalization in prostate cancer xenograft cultures as a result of mutation-rendered δ-catenin truncations. Wildtype and δ-catenin mutants displayed non-overlapping protein interactomes that highlight rewiring of signal networks. Localization specific δ-catenin mutants influenced p120ctn-dependent Rho GTPase phosphorylation and shifted cells towards bFGF-responsive growth, a known signal to bypass androgen receptor dependence. Mutant δ-catenin promoted Myc-induced prostate tumorigenesis by increasing proliferation over apoptosis as well as β-catenin stabilization and HIF-1α expression. Therefore, intratumor δ-catenin heterogeneity by genetic remodeling promotes prostate cancer expansion towards androgen independence, supporting a neomorphism model paradigm for targeting tumor progression.

Citation Format: Mingchuan Li, Jongdee Nopparat, Jiao Zhang, Byron J. Aguilar, Yan-Hua Chen, Jie Du, Xin Ai, Yong Luo, Yongguang Jiang, Christi Boykin, Qun Lu. Intratumor δ-catenin heterogeneity driven by genomic rearrangement dictates growth factor dependent prostate cancer cell fate and behavior [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 2904.
Abstract 2912A: Intratumoral heterogeneity and immune checkpoint inhibitor response in the KPC pancreatic cancer model
Authors: Roth Sarah Martinez
Published: August 2019

Cancer cells are subjected to evolutionary selection and adaptation of clonal populations by changes in the tumor and metastatic microenvironment as well as their response to drug treatment. We wished to evaluate how this tumor heterogeneity impacts the efficacy and responses to immune checkpoint blockade. To understand the contribution of clonal subpopulations to the malignant progression and to the response to drugs, we established a model of tumor heterogeneity from six syngeneic, clonal primary cancer cells isolated from a p48-CRE X LSLmutKras X LSLmutP53 mouse pancreatic cancer (KPC). The clonal cell lines were characterized for genomic mutations, gene expression and tumor allografts reconstituted in syngeneic host mice from mixes of the clonal cell lines. Each of the clonal cells formed invasive and metastatic lesions when grafted into hosts. The original tumor and clonal cell lines harbored common mutations in 99 genes demonstrating their common ancestry. Additional unique mutations in the clonal lines were used to identify and quantitate clones in heterogeneous cell pools. The clones showed different levels of MAP kinase signaling, unique morphologies, different growth rates in vitro and tumor growth rates in immune competent mice. Moreover, the sensitivity to ~200 anticancer drugs revealed an up to 25-fold varying in vitro sensitivity of the clones to signal transduction inhibitors and cytotoxic drugs. Drug sensitivity of individual clones when included in a heterogeneous cell population was strikingly different from their drug sensitivity when growing on their own including the sensitivity of different clones to MEK or PI3K inhibition. Furthermore, the sensitivity of clones to an anti-PD1 checkpoint inhibitor was distinct across the clonal cells growing in the heterogeneous mixture: Some clones were resistant and others highly sensitive to the checkpoint blockade. We will discuss pathways and drivers of resistance as well as sensitivity in the different subpopulations. We conclude that malignant progression and selection of checkpoint inhibitor sensitive cancer cell subpopulations is impacted by the crosstalk between clonal cell populations present in heterogeneous tumors and the host environment.

Citation Format: Sarah Martinez Roth. Intratumoral heterogeneity and immune checkpoint inhibitor response in the KPC pancreatic cancer model [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 2912A.
Abstract 292: PTC596 combination therapy for sarcoma
Authors: Weetall Marla , Branstrom Art , Baird John , Cao Liang , Sheedy Josephine , O'Keefe Kylie , Ingham Matthew , Schwartz Gary K. , Spiegel Robert , O'Mara Edward
Published: August 2019

Sarcomas are rare cancers derived from mesenchymal tissues. Although rare, there are approximately 15,000 new cases of sarcoma diagnosed each year in the United States. Certain soft tissue sarcomas are treated with doxorubicin and olaratumabas first line, gemcitabine as second line, and often dacarbazine (DTIC) as third line. PTC596 is a first-in-class, oral investigational new drug that reduces levels of BMI1, a protein required for cancer stem cell survival. PTC596 acts by binding to tubulin causing a G2M cell cycle arrest. PTC596 lowers levels of BMI1 in preclinical tumor models and is generally well tolerated as a monotherapy at doses that result in preclinical target plasma concentrations. Efficacy of PTC596 was evaluated in a series of preclinical models. PTC596 delayed tumor growth as monotherapy and significantly enhanced, in combination, the activity of standard chemotherapeutics including gemcitabine, doxorubicin/ doxil, dacarbazine (DTIC), and other tubulin binding agents. Based on these results, a Ph1b clinical trial in patients with relapsed refractory leiomyosarcoma is to be initiated. It is a dose escalation study of a combination regimen of dacarbazine and PTC596 with the dose-limiting toxicity (DLT) to be determined using a continuous reassessment methodology. Previously, a Phase I multi-center dose escalation study was conducted in patients with advanced solid tumors. PTC596 was administered as an oral monotherapy in 4-week cycles using bodyweight-adjusted twice-per-week (biw) dosing. A maximum tolerated dose (MTD) was not determined though a well-tolerated recommended Phase 2 dose of 7mg/kg biw was identified. The most relevant toxicities observed were neutropenia, nausea, and vomiting which were generally mild to moderate, manageable and reversible.

Citation Format: Marla Weetall, Art Branstrom, John Baird, Liang Cao, Josephine Sheedy, Kylie O'Keefe, Matthew Ingham, Gary K. Schwartz, Robert Spiegel, Edward O'Mara. PTC596 combination therapy for sarcoma [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 292.
Abstract 2930: Baicalein attenuates radiation-induced enteritis by improving endothelial dysfunction
Authors: Jang Hyosun , Park Sunhoo , Shim Sehwan , Myung Jae Kyung
Published: August 2019

Background: Radiation-induced intestinal injury is frequently observed following clinical application of radiation for abdominal and pelvic cancers or occurs secondary to radiation exposure following a nuclear accident. Radiation-induced enteritis may be considered an ideal model of gastrointestinal inflammation. The endothelium is a crucial component of inflammation, and the endothelial dysfunction following radiation exposure induces the intestinal proinflammatory response and progression of radiation enteritis. Baicalein (5,6,7-trihydroxyflavonoid) is a flavonoid from Scutellaria baicalensis used in oriental herbal medicine. Baicalein has been found to have multiple beneficial properties including antioxidant, anti-inflammatory, anti-allergic, and anti-cancer activities. Here, we investigated the therapeutic effects of baicalein on endothelial dysfunction in radiation-induced intestinal inflammation. Methods: We performed histological analysis, bacterial translocation assays, and intestinal permeability assays, and also assessed infiltration of leukocytes and inflammatory cytokine expression using a radiation-induced enteritis model. In addition, to investigate the effect of baicalein in endothelial dysfunction, we analyzed endothelial-derived adherent molecules in human umbilical vein endothelial cells and irradiated intestinal tissue. Results: Histological damage such as shortening of villi length and impaired intestinal crypt function was observed in the radiation-induced enteritis model. However, intestinal damage was attenuated in baicalein-treated groups with improvement of intestinal barrier function. Baicalein inhibited the expression of radiation-induced adherent molecules in the endothelial cells and increased leukocyte infiltration in the irradiated intestine. We also determined that baicalein could accelerate crypt regeneration via recovery of endothelial damage. Conclusions: Baicalein has a therapeutic effect on radiation-induced intestinal inflammation by attenuating endothelial damage.

Citation Format: Hyosun Jang, Sunhoo Park, Sehwan Shim, Jae Kyung Myung. Baicalein attenuates radiation-induced enteritis by improving endothelial dysfunction [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 2930.
Abstract 2931: The compounding effects of coenzyme q10 and radiation treatment on glial fibrillary acidic protein network of glioma in vitro
Authors: Liao Chong-Chun , Jhunjhunwala Megha , Chung Li-Han , Chen Chi-Shuo
Published: August 2019

Introduction: Astrocytoma is an aggressive primary malignant brain tumor in adults. Radiation therapy is an effective medical treatment, but one of its undesired side-effects is the induced genomic instability of surrounding astrocytes, which can lead abnormal distribution of GFAP and associates with severe brain injury (BI).

Purpose: In order to cope with this serious difficulty, various antioxidants have been applied with radiation therapy. Among antioxidants, Coenzyme Q10 (Q10) is one of the few candidates without double-edged sword effect. However, the understand about Q10 therapeutic effect on radiological protection is limited. In this study, we aimed to investigate the potential therapeutic effects of Q10 on brain tumor radiation treatment.

Materials and Methods: Astrocyte and glioma cell lines were cultivated with Q10 (10μM~ 50 μM) and exposed to 10 Gy single dose from Cobalt-60 (60Co). After the radiation exposure, cell viability was analyzed using MTT assay, GFAP responses was examined by immunofluorescence staining and qPCR, and other cell phenotype indexes, such as the morphology, migration, and invasion in vitro, were observed by microscopy.

Results: Our results indicated that Q10 treatment was capable of maintaining GFAP network of astrocyte after radiation exposure. Besides, Q10 synergistically eliminated glioma proliferation after radiation treatment. By extending horizontally along the base of GFAP remodeling, we further investigated the ability of 3D tumor invasion in co-culture model which simulated the microenvironment composed of reactive astrocyte and glioma in clinical research. Results indicated that radiation therapy with Q10 can further suppress the invasive ability in vitro.

Conclusions: In sum, our results demonstrated the potential radiological protection of Q10 on astrocyte and amplified the therapeutic effectiveness for brain tumor therapy.

Citation Format: Chong-Chun Liao, Megha Jhunjhunwala, Li-Han Chung, Chi-Shuo Chen. The compounding effects of coenzyme q10 and radiation treatment on glial fibrillary acidic protein network of glioma in vitro [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 2931.
Abstract 2939: Developing new therapeutic strategy to bladder cancer by targeting CK1 delta
Authors: Lin Yu-Chen , Chen Mei-chuan , Liou Jing-Ping , Chen Chun-Han
Published: August 2019

Bladder cancer is a common malignancy with high recurrent rate, but targeted therapy other than immune checkpoint inhibitors is currently unavailable. Hence, there is an unmet medical need for the discovery of new therapeutic approach to bladder cancer. By investigating Oncomine database, the mRNA level of CK1 delta is higher in bladder cancer compared to normal tissue, which correlates with survival rate. The aim of this study is to develop new CK1 delta inhibitors and examine their therapeutic potential to bladder cancer as well as the pharmacological mechanisms. Cell viability, cell cycle progression, apoptosis, migration and downstream signaling pathway were analyzed. The results showed that treatment of CK1 delta inhibitors decreased cell viability and inhibited wnt/β-catenin pathway in bladder cancer cell lines. CK1 delta inhibitors increased the accumulation of sub-G1 phase by flow cytometry analysis, as well as the activation of caspase-3, 8, 9 and PARP cleavage by western blot, indicating the promotion of cell apoptosis. Meanwhile, necroptosis was also involved as evident by the rescuing effects by knocking down MLKL in bladder cancer cells. In conclusion, this study demonstrates that CK1 delta is a potential target for bladder cancer therapy in the future.

Note: This abstract was not presented at the meeting.

Citation Format: Yu-Chen Lin, Mei-chuan Chen, Jing-Ping Liou, Chun-Han Chen. Developing new therapeutic strategy to bladder cancer by targeting CK1 delta [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 2939.
Abstract 2942: Cathepsin S inhibition alleviates oxaliplatin-induced peripheral neuropathy through regulation of Ca2+ homeostasis
Authors: Chen Szu-Jung , Shen Meng-Ru , Chen Li-Hsien , Lin Hsiao-Han , Hsu Shih-Han , Chang Jang-Yang
Published: August 2019

Chemotherapeutic drug oxaliplatin is frequently causing chemotherapy-induced peripheral neuropathy. Currently, there is no effective drug to prevent neuropathy in the clinic. Therefore, identification of the potential target to treat to alleviate oxaliplatin-induced neuropathy is urgent. Previously, the release of cathepsin S (CTSS) from microglial cells, which causes neuropathic pain, has been reported, but the detailed mechanism remains unclear. In this study, we discovered that oxaliplatin treatment triggers CTSS expression accompanies with prompted calcium influx from SOCE in vitro. And, the oxaliplatin treated mice displayed increased tail-withdrawal temperature hyperalgesia and impaired locomotor activity along with the loss of neuromuscular function. Furthermore, oxaliplatin-induced peripheral neuropathy was inhibited by the highly selective CTSS inhibitor, 58, which significantly improved the thermal sensitivity and alleviated mechanical allodynia on the heat tail-withdrawal and von Frey tests in oxaliplatin-treated mice, respectively. The grip strength test showed that 58 significantly improved the motor strength and neuromuscular function of oxaliplatin-treated mice. The ultrastructure of sciatic nerve myelin integrity through G ratio quantification supported the observations in our oxaliplatin-induced peripheral neuropathy mouse behavioral tests. Also, inhibition of CTSS enzymatic activity by 58 resulted in the suppression of STIM1 aggregation and decreasing the oxaliplatin-induced calcium influx from SOCE. These results revel a novel molecular mechanism of CTSS in the involvement of oxaliplatin-induced peripheral neuropathy. (This study was supported by the following grants: the National Health Research Institutes (CA-107-PP-22), the Ministry of Science and Technology (MOST 106-2314-B-006-076-MY3)

Citation Format: Szu-Jung Chen, Meng-Ru Shen, Li-Hsien Chen, Hsiao-Han Lin, Shih-Han Hsu, Jang-Yang Chang. Cathepsin S inhibition alleviates oxaliplatin-induced peripheral neuropathy through regulation of Ca2+ homeostasis [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 2942.
Abstract 2948: Novel cell line barcoding method reveals tepoxalin as a selective drug against MDR1-high tumor cells
Authors: Corsello Steven M. , Spangler Ryan D. , Nagari Rohith T. , Kocak Mustafa , Rossen Jordan , O'Hearn Patrick , Roth Jennifer , Gonzalez Alfredo , Dumont Nancy , Doench John , Boehm Jesse S. , Vazquez Francisca , Tsherniak Aviad , Golub Todd R.
Published: August 2019

Drug repurposing for cancer therapy has seen notable success, such as the reintroduction of thalidomide. To discover new indications, all existing drugs known to be safe should be systematically evaluated for anti-cancer properties. However, given cost and throughput considerations, phenotypic screens are typically limited along the cell line (e.g., NCI-60 cell lines) or compound dimension (e.g., testing only several hundred cancer drugs). To identify new repurposing opportunities at scale, we tested more than 4,600 existing drugs for cytotoxicity against 578 diverse cancer cell lines using PRISM, a recently developed multiplexed cell viability assay. High gene expression of the ABCB1 transporter (MDR1/p-glycoprotein) was strongly correlated with resistance to numerous approved cancer therapeutics including taxanes, anthracyclines, vinca alkaloids, and proteasome inhibitors. Surprisingly, we identified a single drug, tepoxalin, with the opposite profile: selective activity against MDR1-high cancer cell lines.

Tepoxalin, an oral cyclooxygenase inhibitor, is FDA-approved for treatment of osteoarthritis in dogs and was previously found to be safe in human trials. To evaluate for alternative mechanism of action and genomic mediators of tepoxalin resistance, we conducted pooled genome-wide CRISPR-Cas9 modifier screens in the LS1034 colorectal cancer cell line. The CRISPR knockout screen revealed ABCB1 as the top enriched gene mediating tepoxalin resistance, while the CRISPR activation screen revealed ABCB1 as the top depleted gene. Overexpression of ABCB1 in ovarian cancer cell lines also sensitized to tepoxalin killing. Small molecule combination testing demonstrated rescue of tepoxalin killing by known ABCB1 inhibitors. Future studies will include biophysical characterization of the interaction between tepoxalin and the ABCB1 protein as well as in vivo efficacy testing. Our results demonstrate that tepoxalin or related derivatives may be useful in the treatment of chemotherapy-resistant colorectal cancer, ovarian cancer, lymphoma, and other malignancies.

Citation Format: Steven M. Corsello, Ryan D. Spangler, Rohith T. Nagari, Mustafa Kocak, Jordan Rossen, Patrick O'Hearn, Jennifer Roth, Alfredo Gonzalez, Nancy Dumont, John Doench, Jesse S. Boehm, Francisca Vazquez, Aviad Tsherniak, Todd R. Golub. Novel cell line barcoding method reveals tepoxalin as a selective drug against MDR1-high tumor cells [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 2948.
Abstract 2959: Deoxysappanchalcone inhibits cell growth by regulation of TOPK signaling pathway in colon cancer
Authors: Zhao Ran , Huang Hai , Choi Bu Young , Song Mengqiu , Yin Fanxiang , Fu Xiaorong , Chen Hanyong , Shim Jung Hyun , Lee Mee-Hyun , Dong Zigang
Published: August 2019

Background: Colorectal cancer is one of the most common cancer death causes in the worldwide. Still systemic chemotherapies are limited to many complications and relapse. T-lymphokine-activated killer cell-originated protein kinase (TOPK) is highly expressed and activated in colon cancer, and plays important roles in inflammation, proliferation and survival of cancer cells. Therefore, suppression of the TOPK activity and its downstream signaling cascades is considered to be a rational therapeutic/preventive strategy of colon cancers.

Purpose: Deoxysappanchalcone (DSC), a component of Caesalpinia sappan L., is a natural oriental medicine. In the present study, we investigated the effects of DSC on colon cancer cell growth and elucidated its underlying molecular mechanism by targeting TOPK.

Study Design and Methods: To evaluate the effects of DSC on colon cancers, we performed cell proliferation assay, propidium iodide- or annexin V-staining analysis and western blotting. Targeting TOPK by DSC was identified by kinase/binding assay and computational docking models. Results: DSC inhibited the kinase activity of TOPK but not mitogen-activated protein kinase (MEK). The direct binding of DSC with TOPK was explored using a computational docking model and binding assay in vitro & ex vivo. DSC inhibited colon cancer cell proliferation, anchorage-independent cell growth, and induced G2/M cell cycle arrest and apoptosis. Treatment of colon cancer cells with DSC induced protein expressions which are involved in cell cycle (cyclin B1) and apoptosis (cleaved-PARP, cleaved-caspase-3 and cleaved-caspase-7), and suppressed protein expressions of extracellular signal-regulated kinase (ERK)-1/2, ribosomal S6 kinase (RSK) or cellular jun (c-Jun) which are regulated by the upstream kinases TOPK.

Conclusion: DSC suppresses colon cancer cell growth by direct targeting TOPK-mediated signaling pathway.

Citation Format: Ran Zhao, Hai Huang, Bu Young Choi, Mengqiu Song, Fanxiang Yin, Xiaorong Fu, Hanyong Chen, Jung Hyun Shim, Mee-Hyun Lee, Zigang Dong. Deoxysappanchalcone inhibits cell growth by regulation of TOPK signaling pathway in colon 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 2959.
Abstract 2976: A comparative study between the therapeutic efficacy of vitamin D3 and its analogue, paricalcitol, in the treatment of colon cancer in rat
Authors: Baghdadi Mohammed Abbas , Aslam Mohammed , Ahmad Jawwad , Idris Shakir , Refaat Bassem
Published: August 2019

Background: Vitamin D3 (VD) and its analogue, Paricalcitol (Pcal), have previously shown anti-tumorigenic activities against colorectal cancer (CRC). Hence, this study compared the therapeutic efficacy of both VD types with or without chemotherapy (5-FU) in azoxymethane (AOM)-induced CRC in rat.

Methods: seventy male Wistar rats were equally allocated into 7 groups: Control, AOM, VD, Pcal, 5-FU, 5-FU/VD and 5-FU/Pcal. AOM was subcutaneously injected for 2 weeks (15mg/kg/week). The study duration was 25 weeks. VD (500 IU/rat/day; 3 days/week) and Pcal (2.5 μg/kg/day; 3 days/week) were injected subcutaneously from week-15 till the end of the study. 5-FU intraperitoneal injections started in week-21 (12 mg/kg/day; 4 successive days) and continued in week-22 (6 mg/kg/4 doses every other day). The colons were collected for gross and histopathological examination. The expression of VD signalling system, Wnt, β-catenin, NF-κB, COX-2, iNOS, VEGF, smad4, p21 and p27 proteins was measured by immune-histochemistry/fluorescence. The mRNA expression of Wnt, β-catenin, DKK-1 and COX-2 genes was measured by Quantitative RT-PCR. ELISA was used to measure the concentrations of TGF-β1, VEGF and COX-2 proteins in tissues.

Results: The AOM and 5-FU groups showed marked inhibitions in the VD receptor and binding protein compared with controls (P < 0.05). VD and Pcal monotherapies significantly increased the expression of the VD molecules and the VD group showed the utmost elevations. Moreover, the tumour numbers and sizes were equally and significantly reduced in the 5-FU, VD and Pcal groups compared with the AOM group (P < 0.05). Interestingly, the 5-FU/VD and 5-FU/Pcal resulted in significantly lower numbers of tumours compared with the remaining study groups and the highest significant reduction was observed in the former group. At the molecular level, the 5-FU/VD markedly inhibited the pro-oncogenic molecules (Wnt, β-catenin, NF-κB, COX-2, iNOS & VEGF) as well as significantly upregulated the anti-tumorigenic molecules (DKK-1, TGF-β1, smad4, p21 and p27) compared with the other study groups (P < 0.05).

Conclusions: Vitamin D3 showed a better synergism than Pcal with 5-FU. The enhanced anti-tumorigenic actions of 5-FU/VD involved the modulation of the Wnt/β-catenin and TGF-β1/smad4 pathways, angiogenesis and cell cycle arrest. Further studies are required to elucidate the therapeutic significance of VD in clinical settings

Citation Format: Mohammed Abbas Baghdadi, Mohammed Aslam, Jawwad Ahmad, Shakir Idris, Bassem Refaat. A comparative study between the therapeutic efficacy of vitamin D3 and its analogue, paricalcitol, in the treatment of colon cancer in rat [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 2976.
Abstract 2989: An all-in-one transcriptome-based assay to identify therapy-related biomarkers in lung cancer
Authors: Kok Klaas , Wei Jiacong , Rybczynska Anna A. , Meng Pei , Terpstra Martijn M. , Wekken Anthonie J. van der , Hiltermann Jeroen T. , Schuuring Ed , Groen Harry J. , Berg Anke van den
Published: August 2019

Background. In the past decade, treatment of advanced stage lung cancer patients guided by somatic aberrations has become routine practice. Different molecular tests are being applied to detect all targetable mutations and fusions. However, in most cases tissue biopsies are small, hampering multiple independent diagnostic tests. To optimize diagnostic testing we developed an all-in-one transcriptome-based assay.

Methods. We have developed a targeted next generation sequencing protocol that uses total RNA as input and is based on the Single Primed enrichment Technology (SPET). We included 11 cell lines, four frozen biopsies, 12 pleural effusion samples and 32 FFPE samples with in total 41 known mutations (including EGFR n=15; KRAS n=11; BRAF n=2; PIK3CA n=3 ), 21 fusion genes (including ALK n=15; ROS n=3) and 3 cases of MET exon14 skipping.

Results. We confirmed presence of 32 out of 41 mutations, 19 out of 23 fusions and all three cases of exon skipping by our assay. Besides confirming the fusions, we were also able to identify the fusion gene partner for all detected fusion transcripts. For the samples for which we failed to detect the mutations or fusions, the read depth of the target region was less than four, indicating low expression, low tumor content or insufficient unique reads. Independent RNA-based ddPCR on six unconfirmed mutations were all positive, albeit with low numbers of mutant droplets in some cases. One of three undetected fusions was positive in a NanoString fusion gene detection assay. For one of two negative cases, the fusion was most likely false positive by FISH, as this patient was FISH-break positive for both ALK and RET, which is never reported before.

Conclusions. This study proved feasibility of this targeted all-in-one transcriptome-based assay for simultaneous detection of mutations and fusions even in relatively small FFPE tissue biopsies. Moreover, we were able to detect the fusion partner genes in all positive cases. We expect that for routine diagnostic testing using an enrichment for tumor cell-rich areas of recently prepared FFPE blocks, the success rate of the all-in-one transcriptome approach will reach similar sensitivity as currently used diagnostic tests.

Citation Format: Klaas Kok, Jiacong Wei, Anna A. Rybczynska, Pei Meng, Martijn M. Terpstra, Anthonie J. van der Wekken, Jeroen T. Hiltermann, Ed Schuuring, Harry J. Groen, Anke van den Berg. An all-in-one transcriptome-based assay to identify therapy-related biomarkers in lung 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 2989.