bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 367: Methods to enhance the optical resolution for 3D-SIM for the study of Hodgkin's lymphoma nuclei
Authors: Szczurek Aleksander T. , Contu Fabio , Vanni Roberta , Knecht Hans , Johnson Nathalie , Haliotis Tina , Mai Sabine
Published: August 2018

In spite of a great deal of knowledge already available, the precise higher order organization of chromatin is still a subject of an debate. Moreover, cancerous cells have an altered chromatin organization in comparison to their healthy counterparts. This is also the case for Hodgkin's lymphoma (HL) - a lymphoid malignancy of B cell origin. HL comprises two cell types, the Hodgkin cells and the diagnostic bi- or multinucleated Reed-Sternberg (RS) cells readily distinguishable from healthy lymphocytes. Patient stratitifcation has been proposed through the quantitative analysis of 3D nuclear telomere organization. With the advent of super resolution microscopy (SRM), further insights into the spatial organization of the cancer genome become feasible. This includes the study of chromatin arrangement with SRM. However, its application to HL remains limited due to technical difficulties: HL cells display thickness of >10µm resulting in light scattering and decreased signal-to-noise ratio.

Structured Illumination Microscopy (SIM, a SRM type) in particular has advanced studies of the sub-cellular structures. It relies on projection of excitation pattern on to a fluorescently labeled sample. Sample's information is then shifted to a detectable band doubling the 3D resolution. Sample's refractive index homogeneity and counteracting photo-bleaching are both crucial for maintenance of the sharp illumination pattern and high-quality SIM, particularly in thick samples. Nevertheless, sample mounting media for SIM have not undergone a significant evolution since almost a decade.

By identification and systematic comparison of non-hazardous components of mounting media we demonstrate increased sample's transparency and consequently improved SIM-quality. Using these novel sample clearing protocols we demonstrate high-resolution chromatin organization at ~120nm level in large RS cells of HL cell lines and in patient samples compared to lymphocytes. This work is of relevance of identification of new diagnostic structural biomarkers for HL.

Citation Format: Aleksander T. Szczurek, Fabio Contu, Roberta Vanni, Hans Knecht, Nathalie Johnson, Tina Haliotis, Sabine Mai. Methods to enhance the optical resolution for 3D-SIM for the study of Hodgkin's lymphoma nuclei [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 367.
Abstract 3687: Dot1l inhibition selectively impairs androgen receptor dependent prostate cancer growth through loss of telomere integrity
Authors: Vatapalli Rajita , Rodriguez Yara , Zhao Changsheng , Sagar Vinay , Anker Jonathan , Pamarthi Sahithi , Unno Kenji , Carneiro Benedito , Chakravarti Debabrata , Abdulkadir Sarki
Published: August 2018

The histone methyltransferase DOT1L methylates lysine 79 (K79) on histone H3 and this histone mark is associated with activation of gene expression. DOT1L has a well-known role in MLL fusion leukemogenesis, however, its role in prostate cancer is yet to be elucidated. Here we show that DOT1L is overexpressed in many solid tumors including prostate cancer and is associated with a poor outcome. Genetic and chemical targeting of DOT1L showed a preferential loss in cell viability and colony formation in androgen receptor (AR)-signaling competent prostate cancer cells, including castration-resistant and enzalutamide-resistant cells. DOT1L inhibition reduced AR levels and upregulated enzymes involved in testosterone catabolism but only affected the expression of a subset of AR target genes. More importantly, loss of DOT1L selectively impaired telomere integrity by promoting telomere uncapping and shortening in AR-signaling competent cells. DOT1L inhibition also reduced the expression of telomerase and Shelterin complex genes including TRF2 and POT1. Recruitment of AR to telomeres and K79 methylation at sub-telomeric regions was also diminished. Consequently, loss of DOT1L leads to induction of Telomere dysfunction induced foci (TIF) and activates a cellular senescence program in these cells. Hence, these results provide compelling evidence for DOT1L inhibition as a novel therapeutic approach in advanced prostate cancers.

Citation Format: Rajita Vatapalli, Yara Rodriguez, Changsheng Zhao, Vinay Sagar, Jonathan Anker, Sahithi Pamarthi, Kenji Unno, Benedito Carneiro, Debabrata Chakravarti, Sarki Abdulkadir. Dot1l inhibition selectively impairs androgen receptor dependent prostate cancer growth through loss of telomere integrity [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 3687.
Abstract 3688: A novel biomarker for pancreatic cancer, sTRA, and CA19-9 define separate subpopulations of PDAC cells with distinctions in behavior and molecular characteristics
Authors: Barnett Daniel , Liu Ying , Gao ChongFeng , Wisniewski Luke , Partyka Katie , Barry Anna , Hostetter Galen , Singhi Aatur , Brand Randall E. , Drake Richard R. , Haab Brian B.
Published: August 2018

Cancer cells in pancreatic ductal adenocarcinomas (PDACs) exhibit tremendous diversity in behavior and phenotype, but no biomarkers are available to identify subtypes with clinically significant differences in behavior. We recently identified a new marker of pancreatic cancer, called sTRA, that is expressed on cancer cells with different morphologies and molecular characteristics than cancer cells expressing the biomarker CA19-9. Here we tested the hypothesis that the two types of cells have differences between them in behavior, gene expression, and associations with outcome. In cell line models, sTRA-expressing cancer cells were more resistant to drugs, more invasive, and slower-growing than the CA19-9-expressing cells. Patient-derived xenograft tumors produced either CA19-9 or sTRA, and RNA-seq analysis revealed significant, nonrandom differences between the sTRA-expressing and CA19-9-expressing tumors. Each subpopulation was found in lymph nodes or livers with levels that significantly correlated with their matched primary tumors. In an analysis of two tissue microarrays covering 45 and 41 patients, the tumors containing high levels of sTRA-expressing cancer cells had the shortest survival times. These data support the existence of two distinct subtypes of PDAC cells, respectively marked by CA19-9 and sTRA. Together the markers could have value for predicting the behavior of tumors and for isolating, characterizing, and targeting specific subtypes of cancer cells.

Citation Format: Daniel Barnett, Ying Liu, ChongFeng Gao, Luke Wisniewski, Katie Partyka, Anna Barry, Galen Hostetter, Aatur Singhi, Randall E. Brand, Richard R. Drake, Brian B. Haab. A novel biomarker for pancreatic cancer, sTRA, and CA19-9 define separate subpopulations of PDAC cells with distinctions in behavior and molecular characteristics [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 3688.
Abstract 3711: Smart therapy: Using CCND1-targeted siRNA-loaded liposomes to sensitize mantle cell lymphoma cells to cisplatin
Authors: Gandhi Tanvi N. , Masamha Chioniso P. , Das Sudip K. , Das Nandita G.
Published: August 2018

Mantle cell lymphoma (MCL) is the most aggressive subtype of B-cell non-Hodgkin's lymphoma, due to its refractory nature and high relapse rate. It is characterized by the aberrant overexpression of the cell cycle regulatory oncogene, cyclin D1 (CCND1), which occurs as a result of a t (11; 14) chromosomal translocation event, the initiating lesion for MCL tumorigenesis. Current therapy includes a series of different chemotherapy regimens often involving a combination of at least four drugs, but there is no gold standard combination treatment regimen. One of the most commonly used drugs in combination treatment is the chemotherapeutic agent, cisplatin. High concentrations of cisplatin in the body cause nausea, vomiting, loss of taste and, more severely, nephrotoxicity. A commonly used approach to reduce the concentration of a chemotherapeutic agent is to use it in combination with a molecular targeting agent. Since cyclin D1 is overexpressed in MCL, we hypothesize that knocking down CCND1 by using siRNA will sensitize MCL cells to cisplatin. We developed CCND1 primers to detect reduction in CCND1 mRNA levels after RNAi using PCR. The greatest challenge against siRNA delivery is its poor stability in vivo and low efficacy of transfection into tumor cells. Our objective is to formulate a dosage form that could be practically adapted in a clinical setting in the future. We developed a liposome formulation that uses a balanced ratio of neutral and cationic lipids to serve as a carrier for the siRNA and improves delivery to tumor cells. Our CCND1 siRNA and control siRNA-loaded liposomes have an average particle size below 150 nm and an overall cationic charge less than 30V. These characteristics are important for the trafficking of the liposome carrier in vivo and its eventual uptake into tumor tissue. Fluorescence assays were used to detect and quantify the amounts of siRNA bound to the liposome. We determined the effect of the liposomes in combination with cisplatin on MCL cell viability using a colorimetric MTT assay. The novel CCND1 siRNA-loaded liposome combined with cisplatin was found to show a dose-dependent decrease in cell viability and was more potent than either CCND1 siRNA liposomes or cisplatin alone (p<0.05). In conclusion, our preliminary studies indicate a potential advantage of using smart therapy by co-administering cisplatin with CCND1 siRNA-loaded liposomes.

Citation Format: Tanvi N. Gandhi, Chioniso P. Masamha, Sudip K. Das, Nandita G. Das. Smart therapy: Using CCND1-targeted siRNA-loaded liposomes to sensitize mantle cell lymphoma cells to cisplatin [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 3711.
Abstract 3721: MMP9 responsive molecular beacon-loaded nanovesicles for imaging and therapy for triple negative breast cancer
Authors: Ranjan Amalendu P. , Fudala Rafal , Shah Sunil , Gdowski Andrew , Kumar Piyush , Grycznski Ignacy , Grycznski Zygmunt , Vishwanatha Jamboor K.
Published: August 2018

African American women are disproportionately affected by triple negative breast cancer (TNBC). Combination of tumor chemotherapy and imaging in an ‘all-in-one system' provides a useful multi-modal approach in the battle against metastatic breast cancer. A promising imaging technique, time gated molecular beacon probes, is a noninvasive and painless method for detection and monitoring. Molecular beacon probe-based theranostic nanoparticles is a novel concept in next-generation medicine that combines simultaneous diagnostics and therapeutics to radically change the way we diagnose, image and treat breast cancer. In this study, we formulated pH sensitive nanovesicles containing molecular beacons specific to MMP-9 for imaging tumor microenvironment along with an anticancer drug, thereby enabling visualization of the tumor together with therapy at the tumor site. This theranostic nanosystem will provide an exciting new tool for breast cancer diagnosis and therapy. Formulation of novel pH responsive nanovesicles were carried out using DMPC and DSPE-PG-8CH. Molecular beacons specific to MMP-9, along with cabazitaxel were encapsulated within the nanovesicles. Characterization of the formulated nanovesicles along with intracellular uptake studies were carried out in breast cancer cell lines. The hydrodynamic diameters of the vesicles were measured using a dynamic light scattering (DLS) instrument (Malvern Zetasizer Nano-ZS) and found to be ~65nm. The zeta potential varied between -55 to -60 mV. Validation of molecular beacon loading in liposome and its stability were done using spectroscopy. Results indicated a molecular beacon loading of ≈29 % in the liposomes and the liposomes were stable for atleast 2 weeks. Comparison of cleavage sequence with time MB and MB-loaded liposome showed that even after 72 hours, molecular beacon released from the liposomes were able to cleave MMP-9 and elicit an effect. This unique and innovative combinatorial theranostic strategy can improve the accuracy of imaging and therapy, provide better assessment of the severity of disease and even monitor the response to drug therapy. This innovative proposal of combining an imaging technique together with delivery of anticancer drug at the tumor site will enhance their clinical potential for diagnosis and therapy in metastatic breast cancer therapy.

Citation Format: Amalendu P. Ranjan, Rafal Fudala, Sunil Shah, Andrew Gdowski, Piyush Kumar, Ignacy Grycznski, Zygmunt Grycznski, Jamboor K. Vishwanatha. MMP9 responsive molecular beacon-loaded nanovesicles for imaging and therapy for triple negative breast cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 3721.
Abstract 3723: Nanoengineered mesenchymal stem cells successfully inhibit tumor progression in a syngeneic mouse model
Authors: Layek Buddhadev , Panyam Jayanth , Prabha Swayam
Published: August 2018

Active tumor-targeted drug delivery holds great promise for enhancing therapeutic efficacy and mitigating toxic side effects resulting from nonspecific distribution of chemotherapeutic agents to healthy tissues. However, the majority of current drug delivery strategies depend on inefficient passive accumulation of the drug carrier in the tumor. We have developed a novel and truly active tumor-targeting approach that relies on the tumor tropism of mesenchymal stem cells (MSCs). Our work emphases nanoengineering of MSCs with paclitaxel-loaded nanoparticles to create cellular drug depots capable of selectively homing to tumor sites and releasing the drug over an extended duration. Paclitaxel-loaded PLGA nanoparticles (18.1 ± 1.9 % w/w paclitaxel; diameter of 282.5 ± 5.2 nm; and zeta potential of −18.4 ± 2.5 mV) were formulated by emulsion-solvent evaporation method. Nanoengineered MSCs were generated by incubating MSCs with 100 µg/mL paclitaxel-loaded nanoparticles for 4 hours at 37°C without altering their viability and migration potential. Anticancer efficacy of nanoengineered MSCs was evaluated in C57BL/6 albino female mice bearing orthotopic Lewis Lung Carcinoma (LL/2-luc) tumors. Despite significantly lower doses of paclitaxel (~2.5 mg/kg total dose for nanoengineered MSCs vs. 120 mg/kg for free- and nanoparticle-encapsulated drug), nanoengineered MSCs resulted in significant greater tumor inhibition and superior survival. Furthermore, administration of human MSCs did not elicit any overt immunologic responses in mice. In summary, our results demonstrate that nanoengineered MSCs can serve as an efficient carrier for tumor-specific delivery of anticancer drugs, resulting in greatly improved therapeutic efficacy.

Citation Format: Buddhadev Layek, Jayanth Panyam, Swayam Prabha. Nanoengineered mesenchymal stem cells successfully inhibit tumor progression in a syngeneic mouse model [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 3723.
Abstract 3724: 5-FU-loaded Nucleoside Nanoparticles for Therapeutic Efficiency of Oral Cancer by various administrations
Authors: FENG HUI , ZHAO Hang , Ji Ning , Li Jing , Wang Zhiyong , jiang lu , Chen Qianming
Published: August 2018

Drug delivery systems are designed to improve bioavailability, reduce degradation, and alleviate the side effect of the loaded drugs. Here, we reported the development of a novel monomeric self-assembled nucleoside nanoparticle (SNNP) into an efficient drug delivery system in such field. Initially, we used a L-configurational pyrimido[4,5-d]pyrimidine nucleoside building nano-bundles and then found its high biocompatibility and low toxicity in vitro and in vivo. Afterwards, the stability in blood circulation and the distribution of 5-FU in OSCC tissues was remarkably increased by the loading with SNNP. Most importantly, 5-FU-SNNP markedly retarded the in vivo growth of OSCC xenografts in mouse models compared with free 5-FU and SNNP by intratumoral, intraperitoneal and intravenous injection, respectively. It was worth mentioning that, SNNP can even reduce the toxic side effects of 5-FU using intraperitoneal injection on OSCC xenograft mouse model. Furthermore, the superior in vivo antitumor efficacy of 5-FU-SNNP compared with free 5-FU and SNNP was related to inhibit cell proliferation and promote cell apoptosis by TUNEL and immunohistochemistry analyses. These findings indicated that when loaded with 5-FU loaded with SNNP has better antineoplastic efficacy using various administrations and lower side-effects, suggesting that this new type of SNNP has a high hope to be a promising candidate nanoparticle-delivery strategy for cancer therapy clinically in the future.

References

Hang Zhao, Hui Feng, Dongjuan Liu, Jiang Liu, Ning Ji, Fangman Chen, Xiaobo Luo, Yu Zhou, Hongxia Dan, Xin Zeng, Jing Li, Congkui Sun, Jinyu Meng, Xiaojie Ju, Min Zhou, Hanshuo Yang, Longjiang Li, Xinhua Liang, Liangyin Chu, Lu Jiang, Yang He, and Qianming Chen. Self-Assembling Monomeric Nucleoside Molecular Nanoparticles Loaded with 5-FU Enhancing Therapeutic Efficacy against Oral Cancer. ACS nano. 2015; 9(10): 9638 - 9651.

The authors gratefully acknowledge support from the National Natural Science Foundation of China (81520108009, 81500860,81700988).

Citation Format: HUI FENG, Hang ZHAO, Ning Ji, Jing Li, Zhiyong Wang, lu jiang, Qianming Chen. 5-FU-loaded Nucleoside Nanoparticles for Therapeutic Efficiency of Oral Cancer by various administrations [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 3724.
Abstract 3787: Exploring the effect of chemotherapies on STING-dependent cytokine release
Authors: Wilkinson Richard D. , Johnston David I. , Parkes Eileen E. , McCabe Nuala , Kennedy Richard D.
Published: August 2018

Introduction: Blockade of PD-1/PD-L1 has shown potent antitumor activity but these therapies are limited to certain diseases with higher intrinsic somatic mutation burden. A key research priority is now optimising response to these agents in diseases with limited clinical response. Activation of the cGAS-STING innate immune pathway has been identified as synergistic with anti-PD-1 therapy, and also a means of overcoming resistance to IO (immune-oncology therapy). We have reported activation of the cGAS-STING immune pathway as a result of cytosolic DNA released in response to intrinsic and extrinsic DNA damage, and that upregulation of PD-L1 in response to DNA damage is dependent on STING. Therefore, activating the STING pathway as a combination treatment with IO therapy could result in improved clinical responses. Experimental procedures: We perform qPCR analysis of the STING target genes, CXCL10/CCL5 after treatment with different classes of chemotherapy. We perform immunofluorescence to determine dsDNA translocation to the cytosol and the requirement of STING for this, an siRNA screening approach was used to identify the key nucleases involved in cytosolic dsDNA translocation and chemokines expression. Results: We observed increased expression of CXCL10/CCL5 gene expression following treatment with the topoisomerase I (irinotecan) and II (Doxorubicin and Etoposide) inhibitors. This chemokine expression was associated with increased expression of dsDNA in the cytosol. Using an siRNA approach, depletion of STING and the DNA nuclease MUS81 demonstrated abrogation of CXCL10/CCL5 expression following treatment with Doxorubicin. Conclusions: Here, we show that topoisomerase I and II inhibitors are the most potent chemotherapy at activating the cGAS-STING pathway and associated expression of interferon-dependent chemokines. We propose that combination therapies of topoisomerase I and II inhibitors with IO therapy will be effective in tumours which have had limited clinical response to single agent IO therapy.

Citation Format: Richard D. Wilkinson, David I. Johnston, Eileen E. Parkes, Nuala McCabe, Richard D. Kennedy. Exploring the effect of chemotherapies on STING-dependent cytokine release [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 3787.
Abstract 3811: Targeted Interleukin 2 and synergy with immune check-point inhibitors
Authors: Hutmacher-Berndt Cornelia Deborah , Neri Dario
Published: August 2018

Systemic high-dose Interleukin 2 (IL2) is able to elicit complete responses in patients suffering from metastatic melanoma. However, the majority of patients cannot receive the whole treatment dose due to severe toxicities. Other approved drugs for the treatment of metastatic melanoma include chemotherapeutics (e.g. Dacarbazine), a protein kinase B-raf inhibitor (Vemurafenib) and an immune check-point inhibitor (Ipilimumab, an anti CTLA-4 antibody). These drugs provide a clear benefit to patients, but cancer cures are still rare.

Targeting IL2 to the site of disease represents a promising strategy to circumvent the toxicity and maximize the efficacy of this immunomodulatory payload. Various formats of targeted IL2 fusion proteins are currently in clinical development. Furthermore, recent successful approaches in the field of immunotherapy focus on the inhibition of check-point pathways, aiming to release the immunosuppressive brakes of the immune system. To explore the possibility of improving therapeutic efficacy of the single agents, a targeted version of IL2 (namely F8-IL2, where the F8 antibody recognizes the alternatively-spliced extra-domain A of fibronectin) was investigated in combination with an anti PD-1, anti PD-L1, or anti CTLA-4 antibody in an immunocompetent mouse model of CT26 colon carcinoma. In a first study, the combination of F8-IL2 and CTLA-4 blockade led to significant tumor growth retardation (curing 3/ 5 mice). Increasing the dose of F8-IL2 from 30 to 45 µg led to a 100 % cure rate with no signs of toxicity (body weight loss <5 %). Moreover, all cured mice acquired protective long-term immunity, which prevented tumor growth upon subsequent rechallenge with CT26 colon carcinoma cells. Furthermore, high dose F8-IL2 combined with the anti PD-1 antibody showed better therapeutic results than the respective monotherapies. In contrast, combination of F8-IL2 with the anti PD-L1 antibody did not improve the therapeutic outcome.

Taken together, these data provide a strong rationale for the clinical use of targeted IL2 in combination with Ipilimumab.

Citation Format: Cornelia Deborah Hutmacher-Berndt, Dario Neri. Targeted Interleukin 2 and synergy with immune check-point inhibitors [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 3811.
Abstract 383: Metabolomic analysis of uterine serous carcinoma with acquired resistance to paclitaxel
Authors: Seino Manabu , Ohta Tsuyoshi , Sakaki Hirotsugu , Sudo Takeshi , Nagase Satoru
Published: August 2018

Introduction: Uterine serous carcinoma (USC) is more aggressive than other subtypes of endometrial carcinoma and is associated with a poor prognosis. We analyzed the metabolomic profile of USC with acquired resistance to paclitaxel.

Method: We compared metabolic profiles and reactions to paclitaxel in both a wild-type USC cell line (USPC-1) and PTX-1, a cell line derived from USPC-1 that acquired paclitaxel resistance, using a capillary electrophoresis CE-MS/MS system.

Results: Glutathione (GSH) concentration in PTX-1 cells was higher than in USPC-1 cells. In addition, GSH concentration in the USPC-1 cells increased after treatment with paclitaxel but was unchanged in PTX-1 cells. Glucose-6-phosphate (G6P) and ribose-5-phosphate (R5P) concentrations in PTX-1 cells were higher than those in USPC-1 cells. G6P concentration in the USPC-1 cells was unchanged after treatment with paclitaxel, while it decreased in PTX-1 cells.

Conclusion: Our results indicate that increased GSH and glucose metabolism may be related to acquiring resistance to paclitaxel in USC and thus may be targets for anti-USC therapy.

Citation Format: Manabu Seino, Tsuyoshi Ohta, Hirotsugu Sakaki, Takeshi Sudo, Satoru Nagase. Metabolomic analysis of uterine serous carcinoma with acquired resistance to paclitaxel [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 383.
Abstract 3844: TAK-659, a SYK kinase inhibitor, demonstrates preclinical antitumor activity in solid tumor models
Authors: Sappal Jessica J. , Theisen Matthew , Xiang Zhongmin , Tirrell Stephen , Christmas Rudy , Yu Jie , Zhang Mengkun , Kannan Karuppiah
Published: August 2018

TAK-659 is a highly potent, reversible inhibitor of spleen tyrosine kinase (SYK) and fms related tyrosine kinase 3 (FLT3) that is currently being investigated in Phase I and II clinical trials. SYK is expressed ubiquitously in hematopoietic cells, and abnormal function of SYK has been implicated in several types of hematopoietic malignancies, including diffuse large B-cell lymphoma (DLBCL), chronic lymphocytic leukemia (CLL), and peripheral T-cell lymphoma (PTCL). Although there are considerable data supporting a role for SYK signaling in hematological cancers, data on the relevance of SYK in solid tumors are emerging. The literature suggests that SYK expression plays a role in the growth of breast and ovarian cancers, and the pancreatic adenocarcinoma microenvironment has been shown to be B-cell rich, giving us a basis to explore the activity of TAK-659 in these indications. Furthermore, ovarian cancer patients with recurrent disease have been shown to have an increase in pSYK at the time of relapse versus at diagnosis, suggesting a role for SYK in chemoresistance. The ability of TAK-659 to inhibit ex vivo colony formation of cells with the ability to grow anchorage independently in semi-solid medium was examined in 31 different human tumor xenografts. TAK-659 showed concentration-dependent inhibition of tumor colony growth in 5/31 tumor models tested, including gastric, breast, and ovarian cancers. Pre-clinically, TAK-659 has exhibited significant antitumor activity in a number of mouse xenograft models of solid tumors. We demonstrate here that daily oral administration of TAK-659 at 60mg/kg over 21 days leads to significant antitumor activity in primary human tumor models of gastric, pancreatic, triple negative breast (TNBC), and ovarian cancers, all of which express pSYK. Significant anti-tumor activity was also observed in the HCC70 TNBC xenograft model which does not express total SYK, demonstrating that TAK-659 may have anti-tumor effects beyond the inhibition of pSYK signaling. A decrease in myeloid derived suppressor cells was seen following TAK-659 treatment in this xenograft model, suggesting an immunomodulatory response may be driving the antitumor activity. Taken together, these data along with published information support the rationale for the investigation of TAK-659 in solid tumor cancer indications.

Citation Format: Jessica J. Sappal, Matthew Theisen, Zhongmin Xiang, Stephen Tirrell, Rudy Christmas, Jie Yu, Mengkun Zhang, Karuppiah Kannan. TAK-659, a SYK kinase inhibitor, demonstrates preclinical antitumor activity in solid tumor models [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 3844.
Abstract 3851: Novel small-molecule inhibitor of PD1/PDL1 pathway demonstrated single agent and drug combo effectiveness in cancer immunotherapy
Authors: Wang Yuguang , Zhou He , Zhang Nong , Wang Feilan , Zhao Qiang , Wu Tianzhi , Zhu Haiyan , Liu Yuzhi
Published: August 2018

With 5 antibodies approved for cancer treatments, PD-1/PD-L1 pathway has been the most successful target in cancer Immuno-therapy. Small molecules that inhibit PD-1/PD-L1 interaction are also attractive because their better tissue penetration may lead to stronger and broader anti-tumor efficacy in addition to more convenient dosing regimen. A series of such small molecule inhibitors have been developed by Maxinovel. Among them, Max 10043 and its 2nd generation compound MAX-10129 potently inhibited PD-1/PD-L1 interaction, reversed PD-L1 suppression of anti-CD3 mediated activation of human T cells, and was well tolerated in animal studies. MAX-10043 also demonstrated anti-tumor efficacy in CT26 murine colorectal carcinoma model. MAX-10129, with improved oral bioavailability, displayed significant inhibition of tumor progression with dose dependency in murine colorectal carcinoma MC-38 model. MAX-10129 also demonstrated synergistic anti-tumor efficacy in different combinations with an anti-CTLA4 antibody, an IDO inhibitor Epacadostat, a COX-2 inhibitor Celebrex and a chemo drug Cisplatin, respectively. The p value of the combo treatment group relative to the vehicle group is less than 0.01 for the Epacadostat combo, the Celebrex Combo and the Cisplatin combo while it is less than 0.05 for the anti-CTLA4 combo. More studies are on-going to illustrate mechanism of action as well as the possibility of all oral triple and quadruple combinations . These data suggest the MAX-10129, a small molecule inhibitor of PD-1/PDL-1 interaction, may represent a novel, orally administrated, safe and effective immunotherapy agent.

Citation Format: Yuguang Wang, He Zhou, Nong Zhang, Feilan Wang, Qiang Zhao, Tianzhi Wu, Haiyan Zhu, Yuzhi Liu. Novel small-molecule inhibitor of PD1/PDL1 pathway demonstrated single agent and drug combo effectiveness in cancer immunotherapy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 3851.
Abstract 386: Heme function in promoting tumorigenic potential of lung cancer cells
Authors: Vidal Chantal , Sohoni Sagar , Zhang Li
Published: August 2018

Heme, also known as iron protoporphyrin IX, is an essential molecule for living organisms. Heme serves as a prosthetic group in enzymes, and acts as a signaling molecule in diverse cellular processes. Mammalian cells can synthesize heme endogenously, or they can import heme from circulation via heme transporters. The synthesis of heme is carried out by eight enzymes, the first of which is the rate-limiting enzyme 5-aminolevulinate (ALA) synthase. Heme can also be transported intracellularly by transporters, such as HCP1 (heme carrier protein 1) and HRG1 (heme responsive gene 1). Finally, levels of heme are also maintained by the degrading enzyme, heme oxygenase-1 (HO-1). HO-1 is localized to the endoplasmic reticulum and is the rate-limiting enzyme in the catabolism of heme. HO-1 cleaves heme to biliverdin and carbon monoxide. Biliverdin is converted to bilirubin, which is an antioxidant and scavenger of ROS. Heme also serves as a catalytic site for various proteins that are involved in aerobic metabolism, such as respiratory chain cytochromes. For example, complex II, III, and IV of the mitochondria require heme for proper function. Importantly, epidemiologic studies have shown the association of dietary heme intake, mainly from red meat, with different cancers, including lung cancer. Therefore, we have analyzed the levels of heme synthesis, uptake, degradation, oxygen consumption and mitochondrial proteins in an immortalized, nontumorigenic human bronchial epithelial cell line (NL20) compared to the tumorigenic counterpart (NL20-TA). These studies showed that the tumorigenic cell line expressed significantly higher levels of heme flux compared to the nontumorigenic cell line. This led us to alter heme availability by overexpressing the rate-limiting enzyme of heme synthesis as well as the rate-limiting enzyme of heme degradation. Experiments are under way to characterize their effects on tumor growth and metastasis.

Citation Format: Chantal Vidal, Sagar Sohoni, Li Zhang. Heme function in promoting tumorigenic potential of lung cancer cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 386.
Abstract 3864: Development of high-specific and sensitive reporter assays for the detection of Wnt/β-catenin signaling activity
Authors: Yamaguchi Kiyoshi , Zhu Chi , Ohsugi Tomoyuki , Saku Akari , Ikenoue Tsuneo , Furukawa Yoichi
Published: August 2018

The Wnt/β-catenin signaling pathway is involved in development, tissue homeostasis, and regeneration. Since aberrant activation of this pathway plays a crucial role in human carcinogenesis, inhibition of this pathway has been shown to be a promising therapeutic strategy for cancers with de-regulated Wnt signaling. Although cell-based assays using synthetic TCF/LEF reporters (also known as TOPFLASH) have contributed to the discovery of small molecules that modulate Wnt signaling pathway, these assays often raise a problem of the specificity in the screening. In this study, we aimed to develop a specific reporter for the detection of Wnt signaling activity. We performed integrated transcriptome analysis and found that expression of histidine ammonia-lyase gene (HAL) is negatively regulated by β-catenin/TCF. In addition to TOPFLASH, we leveraged a promoter region of HAL as another transcriptional readout of Wnt signaling. Subsequently, HepG2 cells stably expressing both optimized HAL promoter reporter and TOPFLASH reporter were established. Since inhibition of the β-catenin/TCF transcriptional activity decreased TOPFLASH activity and simultaneously increased HAL reporter activity, we termed this assay as a bidirectional reporter assay. To verify the effectiveness of this assay, we compared the number of hits in the screening of a test library using the bidirectional assay with that using the conventional TOPFLASH/FOPFLASH assay. Among the 361 compounds in the library, the bidirectional reporter assay identified 9 hits, while the TOPFLASH/FOPFLASH assay did 79 hits. Four compounds were overlapped between these assays, suggesting that the bidirectional assay decreased false positives compared with the conventional assay. The concept of bidirectional assay might be useful for the screening of compounds that regulate other transcriptional factors and/or disease-associated signaling pathways.

Citation Format: Kiyoshi Yamaguchi, Chi Zhu, Tomoyuki Ohsugi, Akari Saku, Tsuneo Ikenoue, Yoichi Furukawa. Development of high-specific and sensitive reporter assays for the detection of Wnt/β-catenin signaling activity [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 3864.
Abstract 3867: Activating ESR1 mutations detection by single ddPCR assay
Authors: Bidard Francois-Clement , Jeannot Emmanuelle , Cabel Luc , Epaillard Nicolas , Ayachy Radouane El , Noret Aurelien , Vincent-Salomon Anne , Pierga Jean-Yves , Bieche Ivan , Proudhon Charlotte , Stern Marc-Henri
Published: August 2018

Background: In metastatic breast cancer, most mutations of ESR1 (which encodes the estrogen receptor alpha ERα) occur in exon 5 (E380Q) and/or 8 (L536, Y537, D538). These mutations are responsible for acquired resistance to hormone deprivation but can be targeted by selective estrogen receptor degraders (SERD) such as fulvestrant. Circulating tumor DNA (ctDNA) allows a non-invasive assessment of ESR1 mutations, but implementing its routine use requires a sensitive, specific and fast technique, at a moderate cost.

Methods: We designed a ddPCR assay scanning for all mutations targeting the 536-538 amino acid residues of ERα with a unique pair of probes and multiplexed it with other probes targeting E380Q. Sensitivity and specificity were assessed in vitro; this multiple hotspot scanning (MHS) ddPCR was used to detect ESR1 mutants in cohorts of patients with hormone deprivation-resistant metastatic breast cancer.

Results: All the above-mentioned mutations were detected in a single MHS ddPCR assay with a high specificity and with a limit of detection of ~0.1% in mutant allele frequency, allowing ESR1 mutant detection in circulating tumor DNA. A perfect concordance with targeted next generation sequencing was observed in the first 31 clinical plasma samples tested. This technique also detected ESR1 polyclonal mutations.

Conclusion: This technique allows for a sensitive, large scale and repeated screening of ESR1 mutants with a single ddPCR assay. The clinical utility of ESR1 mutation detection by this technique is now investigated in the randomized phase 3 PADA-1 trial (sponsors: Unicancer/Gineco), in which patients with rising levels of circulating ESR1 mutants during aromatase inhibitor / palbociclib therapy are eventually switched to fulvestrant / palbociclib (NCT03079011).

ESR1 mutants detectable in a single ddPCR assayAA changesMutant frequency (as per Toy et al, Cancer Discov 2017).E380Q19%L536H4%L536P2%L536R1%Y537S11%Y537C6%Y537N5%Y537D1%D538G32%D538-L539ins1%total % of mutations covered~82% (Many of the 18% remaining mutations occur outside exon 5 & 8 and have no proven functional impact)

Citation Format: Francois-Clement Bidard, Emmanuelle Jeannot, Luc Cabel, Nicolas Epaillard, Radouane El Ayachy, Aurelien Noret, Anne Vincent-Salomon, Jean-Yves Pierga, Ivan Bieche, Charlotte Proudhon, Marc-Henri Stern. Activating ESR1 mutations detection by single ddPCR assay [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 3867.
Abstract 3876: Development and in vitro evaluation of cell membrane lipid-extracted nanoliposomes for lung cancer treatment
Authors: King Jasmine , Bhatt Aarohi , Goodrich Drew , Preteroti Thomas , Alharbi Hanan , Campbell Robert
Published: August 2018

Background: Every year more deaths are attributed to lung cancer compared to colon, prostate, and breast cancers combined. Lung cancer is typically diagnosed at late stages, and has demonstrated poor treatment outcomes due to acquired drug resistance. Unfortunately, as one method is introduced to overcome drug resistance a new mechanism can arise. In an effort to overcome drug resistance lipid extracts (LE) were derived from target cells, and the ingredients were used to develop nanoliposomes that would selectively target a desired cell population compared to controls. The early studies were designed to demonstrate the use of CLENs (cellular membrane lipid-extracted nanoliposomes) for the targeting of lung cancer. Experimental Procedures: CLENs were initially prepared using various ratios of LE/DOPC/Chol/PEG by thin film evaporation. Particle size and zeta potential values were determined for all preparations of CLENs (with and without drug). CLENs were evaluated for selectivity for target compared to control cells. Cytotoxicity studies were performed on various doxorubicin hydrochloride-loaded CLENs using a cell model of lung cancer (ChagGo-K-1). For cellular uptake studies ChaGo-K-1 cells were seeded at 10,000 cells/mL in a 48-well plate and allowed to incubate for 24 hours prior to cell studies. A fluorescence microplate reader was used to determine fluorescence intensity values for the two studies. Results: ChaGo-K-1 CLENs demonstrated an average particle size of 206+/-2 nm and zeta-potential of -21+/-3 mV, illustrating favorable characteristics for drug delivery and interstitial drug targeting. The cellular uptake studies suggested that ChaGo-K-1 CLENs were selective for ChaGo-K-1 cells in vitro, when compared to all other control varieties of CLENs. Drug-loaded ChaGo-K-1 CLENs displayed significant cytotoxicity against ChaGo-K-1 cells compared to control cells. Fluorescence microscopy revealed association of ChagGo-K-1 CLENs with target cells. Conclusions: Based on promising early finding CLENs may represent a relatively tumor specific drug delivery system that can be used to overcome drug resistance, improve efficacy, and to limit off-target drug effects. Preclinical studies will investigate whether the relative selectivity and cytotoxicity observed against lung cancer cells in vitro translates to favorable tumor uptake and efficacy in vivo.

Citation Format: Jasmine King, Aarohi Bhatt, Drew Goodrich, Thomas Preteroti, Hanan Alharbi, Robert Campbell. Development and in vitro evaluation of cell membrane lipid-extracted nanoliposomes for lung cancer treatment [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 3876.
Abstract 3887: Whole exome sequencing to identify genetic markers for trastuzumab-induced cardiotoxicity
Authors: Udagawa Chihiro , Nakamura Hiromi , Ohnishi Hiroshi , Tamura Kenji , Shimoi Tatsunori , Yoshida Masayuki , Yoshida Teruhiko , Okamura Hiroshi , Totoki Yasushi , Shibata Tatsuhiro , Zembutsu Hitoshi
Published: August 2018

Although trastuzumab-induced cardiotoxicity is an important determinant to limit the use of this drug, the molecular mechanism of risk for this toxicity is not well understood. To identify a genetic marker(s) determining the risk of trastuzumab-induced cardiotoxicity, we performed whole exome sequencing of germline DNA samples from 9 patients with trastuzumab-induced cardiotoxicity, and conducted a case-control association study of 2,258 genetic variants between 9 cases (with trastuzumab-induced cardiotoxicity) and general Japanese population controls registered in Human Genetic Variation Database (HGVD). To further validate the result of the screening study, we carried out a replication study of 10 variants showing Pmin < 0.001 in the screening study using 234 independent patients treated with trastuzumab, including 10 cases and 224 controls (without trastuzumab-induced cardiotoxicity). In the replication study, we observed that three variants had effect in the same direction as in the screening study (SNV1 in exon 2 of HERADR1, SNV2 in exon 2 of HERADR2 and SNV3 in exon 44 of HERADR3). A combined result of the screening and the replication studies suggested an association of a locus on chromosome 6q12 with trastuzumab-induced cardiotoxicity (SNV3 in HERADR3, combined-Pmin = 0.00056, OR = 13.73). This finding provides new insights into personalized trastuzumab therapy for the patients with HER2 positive cancer.

Citation Format: Chihiro Udagawa, Hiromi Nakamura, Hiroshi Ohnishi, Kenji Tamura, Tatsunori Shimoi, Masayuki Yoshida, Teruhiko Yoshida, Hiroshi Okamura, Yasushi Totoki, Tatsuhiro Shibata, Hitoshi Zembutsu. Whole exome sequencing to identify genetic markers for trastuzumab-induced cardiotoxicity [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 3887.
Abstract 390: Genome-wide CRISPR screens in brain tumor initiating cells (BTICs) identify potent sensitizers and resistors of conventional chemoradiotherapy
Authors: Chokshi Chirayu , Tieu David , Brown Kevin , Venugopal Chitra , Vora Parvez , Chan Katherine , Tong Amy , Qazi Maleeha , Singh Mohini , Savage Neil , Habsid Andrea , Moffat Jason , Singh Sheila
Published: August 2018

Glioblastoma (GBM) is a highly aggressive and most common form of malignant primary brain tumors in adults (WHO grade IV). Despite surgical and therapeutic interventions, including chemotherapy with the alkylating agent Temozolomide (TMZ) and cranial irradiation, GBM relapse is inevitable with a median survival of <15 months. Extensive intratumoral heterogeneity in GBM is believed to be the leading cause of therapy resistance and disease relapse, suggesting that therapy acts as a bottleneck for tumor evolution. Recently, the advent of CRISPR-Cas9 technology has led to the development of genome-wide libraries of sgRNAs capable of introducing insertion-deletion (indels) within exonic regions of genes, leading to a frameshift mutation two-thirds of the time. Here, we present the first genome-wide CRISPR-Cas9 knockout screen in patient-derived GBM BTICs aimed to discover synthetic lethal sensitizers of conventional chemoradiotherapy. Briefly, we performed genome-wide CRISPR-Cas9 screens in treatment-naïve GBM BTICs subjected to in vitro chemotherapy with TMZ and irradiation. By comparing sgRNA dynamics at each doubling period, we were able to identify potent sensitizer genes exclusive to combined chemoradiotherapy, and not TMZ or irradiation alone. Candidate sensitizer genes were validated in an arrayed format to evaluate impact on GBM BTIC self renewal, proliferation, and sensitivity to TMZ and radiation. We aim to further validate these sensitizers of conventional chemoradiotherapy by performing a focused CRISPR-Cas9 genetic screen in our patient-derived xenograft model of treatment-refractory GBM. Ultimately, adjuvants targeting sensitizer genes could greatly enhance the impact of conventional chemoradiotherapy in GBM patients, leading to an increase in patient survival.

Citation Format: Chirayu Chokshi, David Tieu, Kevin Brown, Chitra Venugopal, Parvez Vora, Katherine Chan, Amy Tong, Maleeha Qazi, Mohini Singh, Neil Savage, Andrea Habsid, Jason Moffat, Sheila Singh. Genome-wide CRISPR screens in brain tumor initiating cells (BTICs) identify potent sensitizers and resistors of conventional chemoradiotherapy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 390.