bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 4502: Cxcl-12-cxcr4 inhibition enhances immune response in pancreatic ductal adenocarcinoma
Authors: Garg Bharti , Ferrantella Anthony , Giri Bhuwan , Modi Shrey , Sethi Vrisketan , Kurtom Saba , Banerjee Sulagna , Sundaram Ramakrishnan , Gilboa Eli , Saluja Ashok , Dudeja Vikas
Published: August 2018

Introduction: Pancreatic ductal adenocarcinoma, one of the most aggressive malignancies and is refractory to Immunotherapy. This, in part, is mediated by the fibrotic stroma, creating an immune-suppressive microenvironment. CXCL12/SDF-1 has been shown to act as a chemo-repellant in several cancers. Therefore, we evaluated the role of stromal CXCL-12 in mediating an immunosuppressive phenotype within the pancreatic tumor.

Methods: Pancreatic cancer cells harvested from KPC, a genetically engineered mouse model for PDAC, were either injected or alone or co-injected with pancreatic stellate cells (PSCs) extracted from WT (C57/BL6) mice to induce tumors. SDF-1 expression levels were detected by IF and q-RT PCR in tumor sections. An SDF-1 inhibitor, AMD3100 (2mg/kg), or vehicle was administered i.p for 21 days in tumor bearing mice and tumor growth and immune infiltration were assessed as an end point by flow cytometry. To evaluate the T cell migration in vitro, PSCs were pre-treated with SDF-1 neutralizing antibody, educated with KPC cancer cells and further co-cultured with splenic CD3+ T cells extracted from KPC mice.

Results: In vitro results showed markedly increased secretion of SDF-1 by PSCs and neutralization of SDF-1 led to increased T-cell migration when cultured with cancer cells alone. We also evaluated the effect of inhibition of SDF-CXCR4 axis on tumor growth. Co-injection of KPC with WT PSC formed larger tumors with increased section of CXCL-12 as compared to when KPC cells were injected alone. Interestingly, Inhibition of SDF-1-CXCR4 interaction with AMD3100 led to reduced tumor growth with increased infiltration of activated CD8+ cytotoxic T cells as compared to the saline-treated mice.

Conclusion: Our results indicate that stromal cells contribute to tumor progression by blocking the infiltration of cytotoxic T cells via secretion of CXCL-12. Targeting CXCL-12 could pave the way for designing better therapeutic interventions against pancreatic cancer.

Citation Format: Bharti Garg, Anthony Ferrantella, Bhuwan Giri, Shrey Modi, Vrisketan Sethi, Saba Kurtom, Sulagna Banerjee, Ramakrishnan Sundaram, Eli Gilboa, Ashok Saluja, Vikas Dudeja. Cxcl-12-cxcr4 inhibition enhances immune response in pancreatic ductal adenocarcinoma [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 4502.
Abstract 4506: Loss of SIRT1 alters the secretome of breast cancer cells by impairing lysosomal integrity
Authors: Latifkar Arash , Ling Lu , Zhang Xiaoyu , Fischbach Claudia , Lin Hening , Cerione Richard , Antonyak Marc
Published: August 2018

Sirtuin 1 (SIRT1) is an NAD-dependent deacetylase implicated in processes ranging from lifespan promotion to tumor suppression. To probe its role as a tumor suppressor, we knocked down SIRT1 in breast cancer cells. This resulted in the decreased expression of one of the subunits comprising the multi-subunit vacuolar-type H+ ATPase (V-ATPase), which is responsible for the acidification of lysosomes and thus essential for proper lysosomal protein degradation. The impairment in lysosomal function led to a marked reduction in the number of multivesicular bodies (MVBs) targeted for lysosomal degradation, and a corresponding increase in MVBs fusing with the plasma membrane to release their content. Specifically, SIRT1 reduction increased the secretion of exosomes containing unique cargo and the release of soluble hydrolases that typically reside in the lysosome, producing a breast cancer cell secretome that strongly promotes cell invasion and survival.

Citation Format: Arash Latifkar, Lu Ling, Xiaoyu Zhang, Claudia Fischbach, Hening Lin, Richard Cerione, Marc Antonyak. Loss of SIRT1 alters the secretome of breast cancer cells by impairing lysosomal 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 4506.
Abstract 4509: SATB2/β-catenin/TCF-LEF pathway induces cellular transformation by generating cancer stem cells in colorectal cancer
Authors: Ma Yiming , Yu Wei , Shankar Sharmila , Srivastava Rakesh K.
Published: August 2018

Recent studies have demonstrated the involvement of colorectal cancer (CRC) stem cells (CSC) in transformation, cancer progression and metastasis. The main goal of this paper was to examine the molecular mechanisms by which SATB2 induced malignant transformation of colorectal epithelial cells. SATB2 induced malignant transformation and these transformed cells gained the characteristics of CSCs by expressing stem cell markers (CD44, CD133, LGR5 and DCLK1) and transcription factors (c-Myc, Nanog and Sox2). Overexpression of SATB2 in normal colorectal epithelial cells increased cell motility, migration and invasion, which were associated with an increase in N-cadherin and Zeb1, and decrease in E-cadherin expression. SATB2 overexpression also upregulated XIAP and cyclin D1, suggesting its role in cell survival and cell cycle. Furthermore, the expression of SATB2 was positively correlated with β-catenin expression in CRC. In contrary, depletion of SATB2 inhibited cell proliferation, colony formation, cell motility and expression of β-catenin, Snail, Slug, Zeb1 and N-cadherin, and upregulated E-cadherin. Furthermore, SATB2 silencing inhibited the expression of stem cell markers, pluripotency maintaining transcription factors, cell cycle and cell proliferation/survival genes and TCF/LEF targets. Finally, β-catenin/TCF-LEF pathway mediated the biological effects of SATB2 in CSCs. These studies support the role of SATB2/β-catenin/TCF-LEF pathway in transformation and carcinogenesis.

Citation Format: Yiming Ma, Wei Yu, Sharmila Shankar, Rakesh K. Srivastava. SATB2/β-catenin/TCF-LEF pathway induces cellular transformation by generating cancer stem cells in colorectal 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 4509.
Abstract 4514: ASR458, a small molecule, targets Notch1 signaling in advanced colorectal cancer
Authors: Chandrasekaran Balaji , Pal Deeksha , Tyagi Ashish , Ramisetti Srinivasa R , Sharma Arun K , Ankem Murali , Damodaran chendil
Published: August 2018

Cancer-related mortality rates are amongst the highest in colorectal cancer (CRC). Previously we have reported that Withaferin A (WA), a natural compound, induces apoptosis and inhibits AKT mediated pro-survival signaling resulting in growth inhibition both in vitro and in vivo models of colon cancer. Owing to the encouraging results with WA, we have developed a series of acetylated pro-drug conjugates of WA and our initial structure-activity relationship (SAR) studies led to the identification of a novel small molecule ASR-458 as the lead compound. Interestingly, ASR-458 has demonstrated better efficacy by inhibiting colon cancer cell growth at nano-molar concentration, even in AKT overexpressing (AKT/HCT) HCT-116 cells (IC50: 750nm). Induction of apoptosis was seen in both control vector and AKT overexpressed colon cancer cell lines. Induction of caspase mediated signaling confirmed the pro-apoptotic function of ASR-458 in colon cancer cells. Inhibition of pAKT (ser473) resulted in downregulation of Notch1 downstream signaling pathways (Presenilin 1, NFkB activation and BCl-2 expression) in AKT/HCT colon cancer cells. Epithelial to mesenchymal transition (EMT) is a major hallmark of metastatic colon cancer. ASR-458 also downregulated the expression of EMT markers snail as well as β-Catenin and significantly impaired invasive as well as the migratory efficiency of AKT/HCT cells. Our ongoing xenograft studies will validate the in vivo efficacy of ASR-458 (1mg/kg/BW by IP weekly 2 times for six weeks) will confirm the chemotherapeutic effect of the compound against colon cancer cells. Overall these results emphasize ASR-458 to be a promising small molecule as compared to WA. ASR-458 targets both AKT and Notch1 signaling pathways which remains an important target for the development of effective treatment of metastatic stage of CRC.

Citation Format: Balaji Chandrasekaran, Deeksha Pal, Ashish Tyagi, Srinivasa R Ramisetti, Arun K Sharma, Murali Ankem, chendil Damodaran. ASR458, a small molecule, targets Notch1 signaling in advanced colorectal 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 4514.
Abstract 4520: Using SEREX approach to screen and identify the tumor-associated antigens in non-small cell lung cancer
Authors: Pei Lu , Wang Tingting , Wang Peng , Liu Hongchun , Ouyang Songyun , Zhang Jianying , Dai Liping
Published: August 2018

Background: Lung cancer is the most common cause of cancer-related deaths worldwide and approximately 85% of lung cancer cases are non-small-cell lung cancer (NSCLC). The average survival and 5-year survival rates of NSCLC patients still remain poor. Autoantibodies against tumor-associated antigens (TAAs) have been shown to be relevant tumor markers. There is an urgent need to better understand the mechanism and to identify useful biomarkers for early immunodiagnosis of NSCLC.

Materials and methods: Serological analysis of recombinant tumor cDNA expression libraries (SEREX) was applied to screen the lung cancer tumor-associated antigens (TAAs) with sera from lung cancer patients. Oncomine online database was used to analyze multiple microarray datasets and to identify potential genes in NSCLC progression. Autoantibody responses to TAAs were evaluated by enzyme-linked immunosorbent assay (ELISA) in sera from 196 patients with NSCLC and 196 normal controls.

Result: Seventy positive clones had been screened by SEREX approach and 35 genes with known biological function were further identified by mass spectrometry analysis. Ten out of 35 genes were determined to be tested the corresponding autoantibodies since they were consistently over-expressed in NSCLC tissue in three mRNA arrays. The results of ELISA show that the level and positive frequency of the autoantibodies to TOP2A,ACTR3, RPS6KA5 and PSIP1 in sera from NSCLC patients were significantly higher than that in normal control (Ρ<0.05). The sensitivity of the four autoantibodies for diagnosis of NSCLC ranged from 17.4% to 32.1% with the specificity of 90%. The area under curve(AUC)of TOP2A,ACTR3, RPS6KA5 and PSIP1 was 0.758, 0.787, 0.707 and 0.668, respectively. The sensitivity of the panel of this four TAAs was 47.2% and the specificity was 81.5%.

Conclusions: TOP2A, ACTR3, PSIP1, RPS6KA5 were tumor-associated antigens and their autoantibodies might be potential biomarkers for immunodiagnosis of NSCLC.

Citation Format: Lu Pei, Tingting Wang, Peng Wang, Hongchun Liu, Songyun Ouyang, Jianying Zhang, Liping Dai. Using SEREX approach to screen and identify the tumor-associated antigens in non-small cell lung 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 4520.
Abstract 453: The role of centrosome amplification in HCC
Authors: Yeung Sai Fung , Ching Yick Pang
Published: August 2018

Centrosome is the major microtubule organizing center (MTOC) in mammalian cells which maintain cell polarity, organization of microtubules and regulate cell cycle progression. In normal cells, centrosome duplication cycle is tightly coupled with cell cycle, DNA synthesis, mitosis as these event were controlled by parallel pathways. Centrosomal defect is reported in numerous type of solid and hematologic malignancy, both structurally (enlarged PCM, string-like etc) and numerically (<2 or >=3). Centrosome amplification (CA, n>=3) is the most commonly reported. CA is casually linked to chromosomal instability (CIN), tumor-initiation, advanced tumor stage and chemo-resistance. CA arises through multiple distinct but non-redundant mechanisms in tumor, for example, aberrant cell cycle, hypoxia, and chemotherapy. Recently studies suggest CA might not be responsible for HCC initiation. Yet, around 90% of HCC cells carry certain degree of CA. It is associated with p53 mutation and tumor-aneuploidy but no other clinicopathological features. The role of CA in HCC progression deserve a more comprehensive study. To investigate the role of CA in HCC, first, we use CA20, an expression signature-score includes centrosomal structural genes and genes results in CA when dyregulated. We use CA20 as surrogate marker to evaluate the clinical outcome of CA in HCC from GEO datasets. CA carrying HCC was found to have poor overall survival and larger tumor size. Next, we developed several inducible PLK4 overexpressing HCC cell line. Preliminary data shown that PLK4 overexpression concomitantly leaded to centrosome over-duplication in HCC cell lines. Functionally, PLK4 overexpression resulted in increased cell migration, but retarded growth rate in p53+/+ HCC cells. Furthermore, we identified another cell cycle-related kinase - Aurora A, as a novel interacting partner of PLK4 suggest that these kinases work together to promote malignant transformation.

Citation Format: Sai Fung Yeung, Yick Pang Ching. The role of centrosome amplification in HCC [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 453.
Abstract 4577: ESR1 methylation: A liquid biopsy-based epigenetic assay for the follow up of patients with metastatic breast cancer receiving endocrine treatment
Authors: Mastoraki Sofia , Strati Areti , Tzanikou Eleni , Chimonidou Maria , Politaki Eleni , Voutsina Alexandra , Psyrri Amanda , Georgoulias Vassilis , Lianidou Evi S.
Published: August 2018

Introduction: Liquid biopsy provides real-time monitoring of tumor evolution and response to therapy through analysis of CTCs and plasma-ctDNA. ESR1 epigenetic silencing potentially affects response to endocrine treatment. We evaluated ESR1 methylation in CTCs and paired plasma-ctDNA. We evaluated ESR1 methylation in CTCs and paired plasma-ctDNA as a potential biomarker for response to everolimus/exemestane treatment. Materials and methods: A highly sensitive and specific real-time MSP assay for ESR1 methylation was developed and validated in: a) 65 primary breast tumors (FFPEs), b) EpCAM+ CTC-fractions (122 patients and 30 healthy donors; HD), c) plasma-ctDNA (108 patients and 30HD), d) in CTCs (CellSearch®) and in paired plasma-ctDNA for 58 BrCa patients. ESR1 methylation status was investigated in CTCs isolated from serial peripheral blood samples of 19 patients with ER+/ HER2- advanced BrCa receiving everolimus/exemestane. Results: ESR1 methylation was detected in: a) 25/65(38.5%) FFPEs, b) EpCAM+ CTC-fractions: 26/112(23.3%) patients and 1/30(3.3%) HD, c) plasma-ctDNA: 8/108(7.4%) patients and 1/30(3.3%) HD. ESR1 methylation was highly concordant in 58 paired DNA samples, isolated from CTCs (CellSearch®) and corresponding plasma. In serial peripheral blood samples of patients treated with everolimus/exemestane, ESR1 methylation was observed in 10/36(27.8%) CTC-positive samples, and was associated with lack of response to treatment (p=0.023 Fisher's Exact Test). Conclusions: We report for the first time the detection of ESR1 methylation in CTCs and a high concordance with paired plasma-ctDNA. ESR1 methylation in CTCs was associated with lack of response to everolimus/exemestane regimen. ESR1 methylation should be further evaluated as a potential liquid biopsy-based biomarker.

Citation Format: Sofia Mastoraki, Areti Strati, Eleni Tzanikou, Maria Chimonidou, Eleni Politaki, Alexandra Voutsina, Amanda Psyrri, Vassilis Georgoulias, Evi S. Lianidou. ESR1 methylation: A liquid biopsy-based epigenetic assay for the follow up of patients with metastatic breast cancer receiving endocrine 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 4577.
Abstract 4602: PTEN and ERG expression in MRI-ultrasound guided fusion biopsy correlated with radical prostatectomy findings in men with prostate cancer
Authors: Erickson Andrew , Lokman Utku , Lahdensuo Kanerva , Tornberg Sara , Visapää Harri , Bergroth Robin , Santti Henrikki , Petas Anssi , Mirtti Tuomas , Rannikko Antti
Published: August 2018

Introduction & Objectives

We previously compared ERG and PTEN protein expression in systematic biopsies with radical prostatectomy (RP) findings. MRI-Ultrasound (MRI-US) guided biopsies are expected to more accurately reflect the biological changes in the RP specimens. Here, we studied the correlation of PTEN and ERG status in MRI-US fusion biopsies (FBx) and RP specimens, and assessed the predictive value of FBx on disease stage and grade at RP.

Material & Methods

The study included patients who had undergone RP in Helsinki University Hospital between June 2015 and May 2017, and had preoperative FBx tissue available (n=110). Matched FBx specimens and tissue microarrays constructed from RP were immunostained with ERG and PTEN antibodies, and scored as either negative or positive. The RP TMA contained one to three clinically relevant cancer foci per patient.

Results

A high correlation of both PTEN and ERG status was observed between FBx and RP materials (Table 1). The correlation of PTEN status was particularly better compared with our previous findings in systematic 12-core biopsies (Lokman et al. 2017), where there was no significant concordance. High grade RP (grade group 4&5) correlated with ERG negativity in FBx (p=0.021), whereas PTEN was lost in high stage RP (pT≥3) to a higher extent than in low stage RP (pT2, p= n.s). Higher FBx grade group was associated with stage increase in RP (p=0.014).

Conclusions

FBx is feasible method to assess ERG and PTEN status correctly in RP specimens. More validation studies, accompanied with MRI features, are warranted.

Table 1A. Concordance of ERG IHC status in fusion biopsies (FBx) and radical prostatectomy (RP) specimens.RP ERG NegativeRP ERG PositiveP-valueFBx ERG Negative54 (90.0)6 (10.0)<0.001aFBx ERG Positive3 (7.1)39 (92.9)Table 1B. Concordance of PTEN IHC (Any PTEN Loss) status in FBx and RP specimens.RP Any PTEN LossRP PTEN IntactP-valueFBx Any PTEN Loss14 (73.7)5 (26.3)0.002aFBx PTEN Intact22 (32.4)46 (67.6)Table 1C. Concordance of PTEN IHC (Complete PTEN Loss) status in FBx and RP specimens.RP Complete PTEN LossRP PTEN IntactP-valueFBx Complete PTEN Loss6 (50.0)3 (50.0)<0.001aFBx PTEN Intact3 (4.0)72 (96.0)aFisher''s exact test. All p-values two-tailed.

Citation Format: Andrew Erickson, Utku Lokman, Kanerva Lahdensuo, Sara Tornberg, Harri Visapää, Robin Bergroth, Henrikki Santti, Anssi Petas, Tuomas Mirtti, Antti Rannikko. PTEN and ERG expression in MRI-ultrasound guided fusion biopsy correlated with radical prostatectomy findings in men with prostate 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 4602.
Abstract 4632: Decitabine for neuroblastoma cure: Target therapy induced ongoing acquisition of RD3 loss and reverts tumor evolution
Authors: Natarajan Aravindan , Somasundaram Dinesh Babu , Aravindan Sheeja , Natarajan Mohan , Herman Terence
Published: August 2018

Recently, we defined the novel tumor evolution stabilization role of Retinal degeneration protein 3 (RD3), regulating the metastatic state of neuroblastoma (NB) cells in vitro and their metastatic potential in vivo. Our earlier studies in various tumor models recognized the role of therapy resistant residual cells in tumor recurrence and relapse. Herein, we investigated the ongoing acquisition of RD3 transcriptional regulation in radiotherapy surviving NB cells and further identified the potential drug candidates that can reprogram and reinstate RD3 transcription in these cells. Human NB (SH-SY5Y, SK-N-AS) cells exposed to single dose (10, 20, 50cGY, 1, 2, 4Gy) or fractionated (FIR, 2Gy/Day for 5 days) irradiation resulted in significant transcriptional repression of RD3. Drug screening with a panel of drugs that are in current clinical use, those in pipelines or in developmental stages by exposing radioresistant cells identified many potential drug candidates that could effectively restore RD3 transcription in this setting. Evidently, we found RD3 promoter region hypermethylation drives its transcriptional regulation in therapy resistant cells. To that note, FDA approved hypomethylating agent decitabine significantly reinforced RD3 transcription in this setting and further promoted cellular differentiation and completely inhibited the formation of organized tumorosphere under stem-cell culture conditions. Together, these results demonstrate the ongoing acquisition of RD3 loss in therapy resistant cells and further recognized the mechanism of how RD3 is regulated in this setting. More importantly, this results of this study identified a drug candidate, that has been already in clinical use, that could be beneficial in mitigating therapy resistance and better clinical outcomes for the patients presented with high-risk advanced disease. Funding: NIH-COBRE-IP20GM103639-01, OUHSC-COM-Radiation Oncology Research Development Funds

Citation Format: Aravindan Natarajan, Dinesh Babu Somasundaram, Sheeja Aravindan, Mohan Natarajan, Terence Herman. Decitabine for neuroblastoma cure: Target therapy induced ongoing acquisition of RD3 loss and reverts tumor evolution [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 4632.
Abstract 4665: Neurotensin receptor-based targeted delivery of thymoquinone for non-small cell lung cancer
Authors: Singh Santosh Kumar , Lillard James W. , Singh Rajesh
Published: August 2018

Non-small cell lung cancer (NSCLC) is a very recalcitrant cancer, accounting for 80% to 85% of all lung cancer diagnoses. About 40% of NSCLC are adenocarcinomas. Thus, there is an urgent need to identify targeted therapies, specifically for NSCLC. Although, multiple signaling molecules have now been identified within the last decade, among them Neurotensin receptor 1 (NTSR1) have afforded an improved understanding of the underlying pathology and significant heterogeneity of NSCLC. NTSR1 belongs to the G-protein coupled receptors (GPCR) superfamily that has been shown numerous oncogenic effects in tumor initiation, progression, proliferation, apoptosis, and metastasis. In the present study, we used a novel method for targeted delivery of Thymoquinone (TQ), a constituent of Nigella sativa at the desired location. We described a proprietary planetary ball milling (PBM) approach that uses a natural polysaccharide (starch; FDA approved) to create a drug-polysaccharide nanoparticle as a core that is subsequently coated with poly (ϵ-caprolactone) / poly (ethylene glycol) copolymer and conjugated with anti-NTSR1-mAb, which allows binding to high-affinity NTSR1 receptors presents on NSCLC. Our tissue microarray data show higher expression of NTSR1 in lung cancer patients, which were negligible in normal cells. These studies were further confirmed by targeting NTSR1 in lung cancer cell lines NCI-H1563, NCI-H1975 and MRC-5 using our novel anti-NTSR1 conjugated, and TQ encapsulated PBM nanoparticle and further, validated using flow cytometry, immunofluorescence, qRT-PCR and western blot techniques. Our result showed the PBM nanoparticles encapsulated with TQ rapidly internalized and depolymerized the microtubule network by inducing apoptosis. The up-regulation of pro-apoptotic (BAX, BID) and down-regulation of anti-apoptotic (BCL-2, MCL-1) makers to confirm the targeted delivery of PBM-NPs to the tumor cells. This study strongly suggests anti-NTSR1-mAb conjugated PBM-NPs has its application to drugs targeting for the treatment of NSCLC. In summary, this study combines innovative ideas with an innovative technology to create new therapeutics and a new strategy to improve the treatment of NSCLC and has the potential to create a new class of targeted treatments for advanced lung cancer.

Citation Format: Santosh Kumar Singh, James W. Lillard, Rajesh Singh. Neurotensin receptor-based targeted delivery of thymoquinone for non-small cell lung 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 4665.
Abstract 4667: The use of fragment-based screening approaches to improve the specificity of inhibitors targeting malignant melanoma
Authors: Mukherjee Sreya , Spriggs Shardell , Wilder Paul , Yu Wenbo , Varney Kristen , MacKerell Alexander D. , Weber David J.
Published: August 2018

S100B belongs to the S100 protein family of Ca2+-binding proteins. Prior studies have shown that S100B is a biological marker for malignant melanoma. Increases in S100B levels are predictive of disease progression, recurrence, and overall low survival in the patients. It was shown previously that S100B binds to p53 and down-regulates its tumor suppression activities including growth arrest and apoptosis. Chemical biology and structure-based drug design methods are underway to inhibit S100B and restore p53 function. However, highly specific S100B inhibitors are required, so S100B can be blocked in melanoma without impairing S100A1 function in skeletal and cardiac muscle. With this goal in mind, a fragment-based screening approach using NMR and computational approaches is being applied. Results to date indicate that these methods can be used to identify specific small molecule fragments that target S100B and not S100A1. The fragments that uniquely bind S100B will then be considered with structural data of existing S100B-SBiX complexes to improve their specificity for binding S100B (i.e. versus S100A1). The inhibitor design strategy will also include improving the stability of the compounds their cell permeability, and their overall drug-like properties. The most promising of these new inhibitors will ultimately be used to target high levels of S100B found in malignant and rescue p53-dependent tumor suppression pathways in vivo with the goal of them having therapeutic value for treating malignant melanoma.

Citation Format: Sreya Mukherjee, Shardell Spriggs, Paul Wilder, Wenbo Yu, Kristen Varney, Alexander D. MacKerell, David J. Weber. The use of fragment-based screening approaches to improve the specificity of inhibitors targeting malignant melanoma [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 4667.
Abstract 4673: Selective delivery of tumor specific antigen to dendritic cells by mannose-labeled PLGA nanoparticles to induce immune response for cancer immunotherapy
Authors: Byeon Yeongseon , Won Ji Eun , Kim Ga Hee , Kim Min Gi , Park Yeong Min , HAN Hee Dong
Published: August 2018

Objective: To overcome limitation of ex vivo manipulation against dendritic cells (DC) vaccines, we developed mannose-labeled poly(d,l-lactide-co-glycolide) nanoparticles (MN-PLGA-NPs). The MN-PLGA-NPs enabled selective delivery of tumor-specific antigen to mannose receptor overexpressed DCs without ex vivo manipulation.

Methods: Conjugation of mannose (MN) and polyvinyl alcohol (PVA) was analyzed by H-NMR. Size and zeta potential of the MN-PLGA-NPs were examined by dynamic light scattering using an electrophoretic light scattering photometer. Selective delivery efficiency of MN-PLGA-NPs to DCs was examined by confocal microscope and flow cytometry. Migration of DCs containing MN-PLGA-NPs was assessed flow cytometry. Therapeutic efficacy of MN-PLGA(OVA+poly I:C)-NPs was examined in EG7 tumor-bearing mouse models. Biological effect and activated CD8+ T cells in tumor tissue were confirmed by immunohistochemistry assay.

Results: Conjugation of MN and PVA was confirmed that the peaks for the CH2 of methylene group in PVA was observed at 1.48 ppm and 1.59 ppm, and CH of tetrahydropyran group in MN was observed at 3.40 ppm, 3.49 ppm, 3.76 ppm, and 5.41 ppm. Size and zeta potential of MN-PLGA-NPs were 200 nm formed spherical shape and -10 mV, respectively. Loading efficiency of OVA or poly I:C into MN-PLGA-NPs was 90 % or 45 %, individually. Intracellular uptake of MN-PLGA-NPs in DCs was increased through selective binding between MN and MN-receptor compared to PLGA-NPs. Additionally, DCs containing MN-PLGA-NPs exhibited efficient migration to popliteal lymph node.

Therapeutic efficacy of MN-PLGA-NPs showed significant inhibition of tumor growth in EG7 tumor-bearing mice compared to the control (p < 0.001) and PLGA-NPs (p < 0.05), and showed 100% of survival up to 60 days. Additionally, MN-PLGA-NPs treatment group showed a greater number of activated CD8+ T cells in tumor tissue compared to the other groups (p < 0.001), and prevention effect of tumor growth resulted in effectively suppressed compared to the control (p < 0.001) or PLGA-NPs (p < 0.001).

Conclusion: MN-PLGA-NPs is an attractive system that can directly activate DC in vivo without ex vivo manipulation, which overcome the limitation of existing DC vaccine.

Keyword: dendritic cells, selective delivery, PLGA nanoparticle, cancer immunotherapy.

Citation Format: Yeongseon Byeon, Ji Eun Won, Ga Hee Kim, Min Gi Kim, Yeong Min Park, Hee Dong HAN. Selective delivery of tumor specific antigen to dendritic cells by mannose-labeled PLGA nanoparticles to induce immune response for 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 4673.
Abstract 4675: B-cell and T-cell repertoire sequencing enables somatic hypermutation and minimal residual disease assessment
Authors: Song Chen , Liu Pingfang , Barry Andrew , Dimalanta Eileen T. , Stewart Fiona J. , Russello Salvatore , Davis Theodore B.
Published: August 2018

The study of complex immunological diseases has progressed through recent developments that enable the sequencing of the immune repertoire. Using this approach, the interrogation of disease progression is facilitated through analysis of millions of V(D)J combinations from both B-cell antibodies and T-cell Receptors (TCR). One major challenge of immune repertoire sequencing is to capture the structural and sequence complexities of antibody and TCR genes. We have developed and optimized a method for accurate sequencing of full-length immune gene repertoires of B-cells and T-cells. RNA extracted from PBMCs were used to generate immune sequencing libraries in duplicate from a single patient. Using a unique barcoding scheme specifically designed to discretely barcode each mRNA molecule with a unique molecule index (UMI), PCR copies of each mRNA fragment can be collapsed into a single consensus sequence, improving accuracy through the resolution of PCR bias and sequencing errors. Utilization of the UMIs enabled absolute quantification of input RNA molecules and accurate ranking of the antibody/TCR clone abundance. This approach was also applied to the analysis of tumor samples for abundance of expanded clones through clustering based on V gene, J gene and CDR3 similarity and ranking by mRNA abundance. The use of isotype-specific primers (IgM, IgD, IgG, IgA and IgE) enabled measurement of the heavy chain isotype proportions within the samples. Full-length heavy chain antibody sequences generated using this method were aligned to germline genes from reference databases, enabling quantitation of the mutation level of each antibody sequence, providing information on the overall maturity and mutational profile of the sample repertoire. Additionally, this approach was capable of detecting minimal residual diseases by sensitive quantification of TCR rearrangement. This novel method allows for exhaustive somatic mutation profiling across complete V, D and J segments and full isotype information analysis. The information obtained enables the possibility for synthesis and expression of complete antibody chains and T-cell receptor chains for downstream immunological assays.

Citation Format: Chen Song, Pingfang Liu, Andrew Barry, Eileen T. Dimalanta, Fiona J. Stewart, Salvatore Russello, Theodore B. Davis. B-cell and T-cell repertoire sequencing enables somatic hypermutation and minimal residual disease assessment [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 4675.
Abstract 4678: High-throughput single-cell linking of antigen specificities with T cell receptor sequences using de novo generated DNA-linked MHC tetramers
Authors: Jiang Ning , Zhang Shu-qi , He Chenfeng , Sun Eric , Zhang Mingliang , Jia Weiping
Published: August 2018

Identification of correlated antigens recognized by T cell and its T cell receptor (TCR) sequences at single cell level is extremely useful to the understanding and treating immune-related diseases. Although mass cytometry, CyTOF, has pushed the number of antigenic peptides that can be interrogated at once to around 100, the destructive nature of CyTOF prohibits linking pMHCs recognized by a T cell with its TCR receptor sequences. In addition, the high cost associated with peptide synthesis process prevents the quick generation of a peptide library that can be tailored to any pathogens or diseases. Here we describe a new technology, TetATCR-Seq for Tetramer Associated TCR sequencing, that is capable of de novo generating a large amount of peptides and mapping antigen recognition with single cell TCR sequences by DNA barcoded tetramers. It evolves three major steps: 1) de novo peptide generation, 2) DNA barcoded tetramer generation, and 3) single cell sequencing of tetramer DNA barcode and TCR sequences. By spiking in 5 altered peptide ligands (APL) that are known to bind to a HCV T cell clone with other 90 irrelevant peptides, we showed that the binding of all these 5 APLs can be faithfully detected by sequencing while non-specific binding is minimum. Using a published set of cancer neo-antigen sequences, we showed that these peptides and their wild type counterparts can be quickly generated. Resulted tetramers can be used to clearly identify a population of neo-antigen only or wild type antigen only or double positive T cells. Subsequent single cell TCR sequencing showed that TCR paired α and β chain sequences can be obtained in more than 80% of single sorted T cells. Simultaneous tetramer DNA barcode sequencing showed that many T cells are found to cross-reactive to both neo-antigen and its wild type counterpart, suggesting the necessity of strict screening for neo-antigen only TCR in adoptive cell transfer therapy. In summary, the TetaTCR-seq tool we developed here enables one to quickly survey antigen repertoire again TCR repertoire at single cell level for a large number of peptides. This is an extremely useful tool in profiling T cell repertoire reactivity in infection and vaccination. It is also a useful tool to screen for T cell cross-reactivity and select neo-antigen specific TCR for cancer immunotherapy.

Citation Format: Ning Jiang, Shu-qi Zhang, Chenfeng He, Eric Sun, Mingliang Zhang, Weiping Jia. High-throughput single-cell linking of antigen specificities with T cell receptor sequences using de novo generated DNA-linked MHC tetramers [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 4678.
Abstract 4692: High density of cytotoxic and regulatory T-lymphocytes in gastric cancers with microsatellite instability
Authors: Kim Hyoung-Il , Shin Su-Jin , Kim Sang Yong , Choi Yoon Young , Son Taeil , Cheong Jae-Ho , Hyung Woo Jin , Noh Sung Hoon
Published: August 2018

Introduction: MSI-high (MSI-H) colorectal cancer is known to be associated with increased tumor-infiltrating lymphocytes (TILs) and good prognosis. In gastric cancer, however, MSI status has rarely been evaluated in accordance with TILs. The objectives of our study were to clarify the relationships between MSI status and antitumor host immune response and to identify the impact of these factors on the prognosis of gastric cancer.

Methods: We evaluated 345 patients with gastric cancer who underwent gastrectomy with MSI typing. The numbers of TILs in tumor center was counted after immunohistochemical staining with anti-CD3, CD4, CD8, Foxp3, and granzyme B to quantify the subset of TILs. To evaluate systemic immune response, differential white blood cell count and prognostic nutritional index (PNI) were obtained.

Results: Of the 345 patients, 57 were MSI-H and 288 were non-MSI-H groups. MSI-H tumors carried significantly higher numbers of CD8+ T-cells, Foxp3+ T-cells, GZB+ T cells and higher ratio of Foxp3/CD4 and GZB/CD8. The prognostic effect of TILs was different in MSI-H and non-MSI-H groups. All subsets of TILs were not significant prognostic factor for recurrent-free survival (RFS) and overall survival (OS) in MSI-H group. However, in non-MSI-H group, multivariate analysis showed that stage, PNI and CD4+ T cells was independent prognostic factor for RFS; on the other hand, stage, PNI and ratio of Foxp3/CD4 was independent prognostic factor for OS.

Conclusions: The number of subset of TILs and the prognostic influence of systemic and local immune response were different between MSI-H and non-MSI-H tumors. The immunogenicity caused by microsatellite instability and subsequent host immune response is associated with cancer progression and patient prognosis of gastric cancer.

Citation Format: Hyoung-Il Kim, Su-Jin Shin, Sang Yong Kim, Yoon Young Choi, Taeil Son, Jae-Ho Cheong, Woo Jin Hyung, Sung Hoon Noh. High density of cytotoxic and regulatory T-lymphocytes in gastric cancers with microsatellite instability [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 4692.
Abstract 4695: Murine tumor growth suppression through CD8+CTLs via activated DEC-205+dendritic cells by sequential administration of α-galactosylceramide in vivo
Authors: Kogo Hideki , Takahashi Hidemi , Uchida Eiji
Published: August 2018

Cancer immunotherapy is mediated by the effective priming and activation of tumor-specific class I major histocompatibility complex molecule-restricted CD8+ cytotoxic T lymphocytes. DEC-205+ dendritic cells can cross-present the epitopes of captured tumor antigens associated with class I MHC molecules alongside co-stimulatory molecules to prime and activate tumor-specific CD8+ CTLs. Immunosuppressive tolerogenic DCs with reduced co-stimulatory molecules may be a cause of insufficient CTL induction. Hepa1-6-1 cells were established from the mouse hepatoma cell line Hepa1-6; these cells grow continuously after subcutaneous implantation into syngeneic C57BL/6 mice and do not prime CD8+ CTLs. Here, we show that the growing of tumors was suppressed by activated CD8+ CTLs with tumor-specific cytotoxicity through the administration of the glycolipid α-galactosylceramide, which is a compound known to stimulate invariant natural killer T cells and selectively activate DEC-205+ DCs. Moreover, we demonstrated that sequential repetitive intraperitoneal inoculation of α-GalCer every 48 hour appeared to convert tolerogenic DEC-205+ DCs into immunogenic DCs with a higher expression of co-stimulatory molecules and a greater cross-presentation capacity, which primed CTL precursors and induced tumor-specific CD8+ CTLs within the tumor environment without activating iNKT cells. These findings provide a new basis for cancer immunotherapy to convert tolerogenic DEC-205+ DCs within tumors into immunogenic DCs via the sequential administration of an immuno-potent lipid/glycolipid, and activated immunogenic DCs expressing sufficient suitable co-stimulatory molecules will prime and activate tumor-specific CD8+ CTLs within the tumor to control tumor growing.

Citation Format: Hideki Kogo, Hidemi Takahashi, Eiji Uchida. Murine tumor growth suppression through CD8+CTLs via activated DEC-205+dendritic cells by sequential administration of α-galactosylceramide in vivo [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 4695.
Abstract 4705: The novel oncolytic peptide, DTT-304, induces regression of colorectal cancer tumors in vivo
Authors: Fleten Karianne G. , Eksteen Johannes J. , Mauseth Brynjar , Camilio Ketil , Rekdal Øystein , Wang Meng Yu , Mælandsmo Gunhild M. , Flatmark Kjersti
Published: August 2018

Colorectal cancer (CRC) is the third most common cancer in the world, and approximately 50% of the patients develop liver metastasis, which is a major cause of disease mortality. New drugs and treatment options are therefore necessary to improve the survival of these patients. Lately, different types of immunotherapy, such as check point inhibitors, have shown great promise in the treatment of metastatic cancer, although for most patients with CRC the efficacy has been restricted to cases with microsatellite instable disease. Another novel immunotherapeutic strategy is oncolytic immunotherapy, which has been shown to cause immunogenic cancer cell death. Following cancer cell lysis, damage associated molecular patterns (DAMPs) are released, which are recognized by immune cell receptors. Pro-inflammatory responses will then be triggered to induce release of tumor specific antigens that are presented to the immune system, leading to tumor-specific immune responses.

In the present study, we have investigated the efficacy of a novel oncolytic peptide, DTT-304, using two mouse models. Subcutaneous tumors were established in Balb c mice using the cell line CT26 and in C57Bl6 mice using the cell line MC38, both murine CRC cell lines. In both models, intra-tumoral injection of the peptide induced tumor necrosis and complete regression a few days after initiation of treatment, thus showing the potential of this peptide for use in colorectal cancer.

In ongoing experiments we are investigating if the peptide has the potential to induce long lasting protective tumor-specific immune responses by re-challenging previously treated mice with the same cell line in a liver metastasis model. In addition, the possibility of treating liver tumors by direct peptide injection will be investigated.

Citation Format: Karianne G. Fleten, Johannes J. Eksteen, Brynjar Mauseth, Ketil Camilio, Øystein Rekdal, Meng Yu Wang, Gunhild M. Mælandsmo, Kjersti Flatmark. The novel oncolytic peptide, DTT-304, induces regression of colorectal cancer tumors in vivo [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 4705.
Abstract 4708: Imprime (beta-1,3/1,6 glucan) synergizes with a CD40 agonist to stimulate T cell-dependent antitumor activity in a poorly immunogenic model of pancreatic carcinoma
Authors: Liu Mingen , Graham Kathleen , Chan Anissa S. , Ottoson Nadine R. , Bose Nandita , Beatty Gregory L.
Published: August 2018

Introduction: While some solid tumors show remarkable sensitivity to immunotherapy, pancreatic ductal adenocarcinoma (PDAC) has demonstrated impressive resistance. This poor responsiveness to immunotherapy may reflect multiple mechanisms necessary for generating productive T-cell immunosurveillance, including ineffective tumor antigen presentation by myeloid cells. Here, we hypothesized that combining two immune agonists capable of “licensing” myeloid cells with enhanced T-cell stimulatory properties would synergize to reverse the poorly immunogenic state of pancreatic cancer and, in doing so, drive productive T cell-dependent antitumor immunity.

Methods: C57BL/6 mice were challenged subcutaneously with a syngeneic PDAC cell line (7940B.PDA) derived from a tumor arising spontaneously in the KrasG12D/+; Trp53R172H/+; Pdx-1 Cre (KPC) mouse model. Mice with tumors measuring approximately 5 mm3 in diameter were treated with defined combinations of gemcitabine chemotherapy, a CD40 agonist (FGK45), and Imprime (a yeast β-1,3/1,6 glucan that coordinately activates innate and adaptive immune responses through pattern recognition receptors). CD4 and CD8 T cells were depleted in vivo using GK1.5 and 2.43 antibodies, respectively. Tumor growth curves and overall survival were determined.

Results: Monotherapy with Imprime or a CD40 agonist only modestly delayed tumor outgrowth compared to chemotherapy alone. Delivering chemotherapy 48 hours prior to Imprime administration produced a two-fold increase in the median overall survival, but responses were not durable and all mice relapsed. In contrast, concurrent single administration of Imprime and a CD40 agonist induced complete and durable regressions in 60% of mice. Tumor-free mice resisted tumor rechallenge and therapeutic efficacy was completely abrogated with CD4/CD8 cell depletion.

Conclusions: The combination of two myeloid-directed immune agonists (Imprime and a CD40 agonist) shows promising activity for stimulating T cell-dependent antitumor immunity against PDAC, a poorly immunogenic cancer.

Citation Format: Mingen Liu, Kathleen Graham, Anissa S. Chan, Nadine R. Ottoson, Nandita Bose, Gregory L. Beatty. Imprime (beta-1,3/1,6 glucan) synergizes with a CD40 agonist to stimulate T cell-dependent antitumor activity in a poorly immunogenic model of pancreatic carcinoma [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 4708.