bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 1201: Amentoflavone inhibits cell growth and metastasis in colorectal cancer was associated with the suppression of KIAA1199
Authors: Ku Hsiang-Ju , Tan Zhao-Lin , Chiang I-Tsang , Chang Yuan , Hsu Fei-Ting
Published: July 2021

Amentoflavone (AF), a kind of diflavonoid compound, which was used as a traditional folk medicine thousands years ago. AF had been proven to prevent cells degeneration, aging, and could also induce cell cycle arrest and apoptosis in various human cancer cells to achieve anti-tumor effects. Cell migration-induced hyaluronic acid binding protein (CEMIP, KIAA1199), an oncogene protein, has been confirmed to be associated with the abnormal expression of epithelial-mesenchymal transition (EMT) markers. Several studies also reported that the inhibition of KIAA1199 can suppress the proliferation of colorectal cancer (CRC). At present, there is no study identify whether AF can inhibit the growth of colorectal cancer by regulating KIAA1199. The aim of this study was to investigate the anticancer effect and mechanism of AF in colorectal in vitro and in vivo. First, we indicated that the cytotoxic effect was induced by AF in human and mouse CRC (CT26 & HT29) cells. The fewest colony formation was found in AF treated group, which represent the suppression of proliferation. Cell cycle was arrest at G1 by AF treatment which was evaluated by flow cytometry. Then, the migration and invasion suppression was also found in amentoflavone treatment group by wound healing and invasion/migration transwell assay. Furthermore, real-time polymerase chain reaction detection and Western blotting results indicated that KIAA1199 related genes, such as E-cadherin, N-cadherin, Vimentin and Fibronectin were all downregulated by amentoflavone. In animal experiments, the CRC tumors volume were reduced in AF treatment groups. In summary, AF can achieve therapeutic effects in colorectal cancer by inhibiting cell proliferation, migration/invasion ability and EMT potential via suppression of KIAA1199.

Citation Format: Hsiang-Ju Ku, Zhao-Lin Tan, I-Tsang Chiang, Yuan Chang, Fei-Ting Hsu. Amentoflavone inhibits cell growth and metastasis in colorectal cancer was associated with the suppression of KIAA1199 [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 1201.
Abstract 1202: ERG344: A novel IRG1 inhibitor for the treatment of colon cancer
Authors: Papathanassiu Adonia E. , Lodi Francesca , Vu Hong A. , Lambrechts Diether
Published: July 2021

Immune responsive gene 1 (Irg1) is an LPS-inducible gene within macrophages (MF) whose protein product is responsible for the synthesis of itaconate from aconitate through a break in the TCA cycle. Although primarily present in proinflammatory macrophages, IRG1 expression has been linked with certain cancers (glioblastoma, ovarian carcinoma) and its tumor-driven upregulation in peritoneal resident macrophages (pResMF) has been shown to contribute to peritoneal tumor growth. Here, we report Irg1 gene expression at the single cell level (scRNAseq) in samples obtained from colorectal cancer patients (n=7; ~11,000 single cells). Transcriptomic analysis showed that Irg1 was primarily expressed by cancer cells, although other tumoral cell types also showed substantial levels of the gene. To determine if IRG1 is a druggable target in cancer, we synthesized a series of small MW inhibitors and selected ERG344 for in vivo testing based on its ability to inhibit itaconate synthesis in a rat glioblastoma cell line (C6) engineered to stably express Irg1. The IC50 value of inhibition was ~150 μM. In vivo, ERG344 suppressed tumor growth and increased survival probability in a syngeneic colon cancer model (CT26). Drug administration was initiated when the tumors reached an average tumor volume of ~100 mm3 and involved daily ERG344 doses of 0.2 mg/kg ip or 0.3 mg/kg po. Complete tumor regressions (~17%) were observed in the same model when ERG344 was administered ip at 3 mg/kg. Immunophenotyping of CT26 tumors treated with either vehicle or 0.2 mg/kg ERG344 ip indicated that IRG1 inhibition renders the tumor microenvironment less immunosuppressive by decreasing the frequency of monocytic myeloid suppressor cells (m-MDSCs), increasing the frequency of cytotoxic CD8+ T cells, and decreasing the CD8+ expression of the negative co-stimulatory molecule PD-1. To determine if ERG344 is also able to reduce pResMF-driven peritoneal tumor growth, murine melanoma B16F15 cells were injected into the peritoneal cavity of C57BL/6 mice treated with vehicle or 1 mg/kg ERG344 (n=8/group). Seven days after tumor inoculation, mice treated with ERG344 showed reduced tumor growth in the peritoneal cavity, which led to increased survival probability of the animals. The studies collectively suggest that IRG1 is a novel target for the treatment of primary and metastatic tumor growth in colorectal cancer and highlight the therapeutic potential of ERG344.

Citation Format: Adonia E. Papathanassiu, Francesca Lodi, Hong A. Vu, Diether Lambrechts. ERG344: A novel IRG1 inhibitor for the treatment of colon cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 1202.
Abstract 1208: Identifying a novel glycolytic inhibitor for treatment of aggressive prostate cancer
Authors: Stoyanova Tanya Ivanova
Published: July 2021

Among men, prostate cancer is the second leading cause of cancer-associated mortality, with advanced disease remaining a major clinical challenge. Chalcones are a major class of widely occurring natural products that are intermediates in plant flavonoid isoflavonoid synthesis. They are characterized by an α,β-unsaturated carbonyl structure with two aromatic rings and commonly act as free-radical scavengers.

Herein, we describe a chalcone derivative, SU086, as an anticancer agent for prostate cancer. Proteomic and metabolomic profiling demonstrate that SU086 impairs glycolysis, a critical pathway for cancer growth and survival. SU086 inhibited prostate cancer cell growth, migration, and invasion in vitro. Moreover, SU086 significantly delayed the tumor growth of cell line-derived xenograft models of CRPC as well as patient-derived xenografts (PDXs) in vivo, and the proliferation of primary human prostate cancer patient-derived tissues ex vivo. Furthermore, SU086 strongly synergized with standard of care second-generation anti-androgens, enzalutamide and abiraterone, in inhibiting prostate cancer cell growth in vitro and tumor growth in vivo.

Our study identifies SU086 alone or in combination therapy settings as a novel treatment for aggressive prostate cancer. We demonstrate that SU086 represents a highly effective therapeutic strategy for both AR-sensitive and AR-insensitive prostate cancers and may potentially be applicable across multiple cancer types.

Citation Format: Tanya Ivanova Stoyanova. Identifying a novel glycolytic inhibitor for treatment of aggressive prostate cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 1208.
Abstract 1215: Targeting TIP1 with a novel radiosensitizing antibody-drug conjugate (ADC) enhances the therapeutic efficacy of radiation for non-small cell lung carcinoma treatment
Authors: Lewis Calvin , Singh Abhay K. , Thotala Dinesh , Hallahan Dennis E. , Kapoor Vaishali
Published: July 2021

Tax-interacting protein 1 (TIP1) is a multifunctional protein involved in cellular motility, cellular adhesion, migration, cancer cell protection from ionizing radiation, and metastasis. We found that TIP1 is a radiation inducible antigen that is translocated to the cancer cell surface. Antibody-drug-conjugates (ADCs) are emerging as promising anti-cancer immunoconjugates. ADCs carry antitumor payloads and allow site-specific targeting of cancer with increased cytotoxicity and decreased side effect profiles as compared to conventional chemotherapy. Monomethyl auristatin E (MMAE) is a potent radiosensitizing microtubule inhibitor with enhanced cancer cytotoxicity in combination with radiotherapy. We developed ADCs against radiation-inducible TIP1 for lung cancer treatment in combination with radiation. Out of the various anti-TIP1 antibodies, we prioritized the lead antibody that shows high affinity to TIP1 protein on the cancer cell surface and in vivo irradiated lung cancers. Our lead antibody, 7H5 undergoes endocytosis in cancer cells in vitro. We conjugated 7H5 to VcMMAE. Hydrophobic interaction chromatography (HIC) was performed to determine drug-to-antibody ratio (DAR). We obtained an average DAR of 3.7. Cytotoxic potential of 7H5-VcMMAE was evaluated in A549 and H1299 NSCLC cells. Cells were exposed to 7H5-VcMMAE or 7H5-antibody alone at various doses. At 10nM concentration, ~70% reduction in viable cells was observed following 7H5-VcMMAE treatment compared to 7H5 alone in both A549 (p=0.0032) and H1299 cells (p=0.0010). 7H5-VcMMAE sensitized A549 and H1299 cells to radiation as observed by significantly decreased (p<0.001) surviving fraction compared to 7H5 alone. In vivo therapeutic efficacy of the 7H5-VcMMAE was determined using mice bearing hind-limb human NSCLC tumors. The ADC showed a prolonged delay in tumor growth and improved tumor control was achieved with IR + 7H5-VcMMAE in A549 and H1299 hind-limb tumor models. Furthermore, mice in all groups displayed no toxicity associated with treatment. Our study suggests that targeting radiation-inducible TIP1 with a radiosensitizing ADC is a promising strategy to enhance therapeutic efficacy in lung cancer. This novel approach of targeting cancer using ADCs to radiation-inducible antigens will lead to clinical trials in lung cancer patients treated with radiotherapy.

Citation Format: Calvin Lewis, Abhay K. Singh, Dinesh Thotala, Dennis E. Hallahan, Vaishali Kapoor. Targeting TIP1 with a novel radiosensitizing antibody-drug conjugate (ADC) enhances the therapeutic efficacy of radiation for non-small cell lung carcinoma treatment [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 1215.
Abstract 1219: Deep mutational scanning of PDE3A identifies residues required for DNMDP response
Authors: Wu Xiaoyun , Papanastasiou Malvina , Schnitzler Gavin , Garvie Colin , Hoyt Stephanie , Zhang Terry , Mullahoo James , Baker Andrew , McGaunn Joseph , Kaplan Bethany , Lee Sooncheol , Lange Martin , Carr Steven , Yang Xiaoping , Piccioni Federica , Cherniack Andrew , Meyerson Matthew , Greulich Heidi
Published: July 2021

PDE3A-SLFN12 complex formation is induced by a class of compounds, now called “velcrins”, exemplified by the small molecule, DNMDP. Cancer cells that express elevated levels of PDE3A and SLFN12 are sensitive to a velcrin-mediated cytotoxic response, which is independent of PDE3A inhibition. However, the details of complex formation have not yet been revealed. We solved the crystal structure of PDE3A with a series of ligands bound to the active site and found that PDE3A exists as a dimer, and velcrin binding does not cause any obvious structural changes in the PDE3A protein structure. Hydrogen-deuterium exchange (HDX-MS) experiments with velcrin-bound PDE3A in the absence and presence of SLFN12 identified three regions of PDE3A that are shielded from solvent as a result of velcrin-induced SLFN12 binding. Two of these regions are near the velcrin binding site, and the third region lies at the PDE3A homodimerization interface. In order to further investigate the structural relationship between PDE3A, DNMDP, and SLFN12, we took a deep-mutation scanning (DMS) approach to identify residues of PDE3A that impact DNMDP sensitivity. A library of PDE3A alleles was developed in which the sequence encoding amino acids 668-1141, including the PDE3A catalytic domain, was substituted with a codon for every other possible amino acid or a stop codon in the context of the full-length cDNA. The library was transduced into PDE3A-knockout GB1 glioblastoma cells and assessed for survival in the presence of DMSO or DNMDP. Corroborating the HDX-MS data, we identified three regions of PDE3A in which missense mutations abrogated DNMDP response: the active site, the homodimerization surface, and an alpha helix containing amino acid F914. We confirmed that mutations of F914 and the homodimer interface retain the ability to bind resin-conjugated compound but fail to complex with SLFN12. Taken together, the HDX and DMS results suggest that PDE3A dimerization is required to stabilize velcrin-induced SLFN12 binding and implicate the alpha helix containing F914 as the SLFN12 binding interface of PDE3A.

Citation Format: Xiaoyun Wu, Malvina Papanastasiou, Gavin Schnitzler, Colin Garvie, Stephanie Hoyt, Terry Zhang, James Mullahoo, Andrew Baker, Joseph McGaunn, Bethany Kaplan, Sooncheol Lee, Martin Lange, Steven Carr, Xiaoping Yang, Federica Piccioni, Andrew Cherniack, Matthew Meyerson, Heidi Greulich. Deep mutational scanning of PDE3A identifies residues required for DNMDP response [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 1219.
Abstract 1221: The landscape of 2,706 RET alterations from 89,754 adult patients with cancer: Clinical implications
Authors: Adashek Jacob J. , Andreev-Drakhlin Alexander , Roszik Jason , Desai Aakash P. , Subbiah Vivek
Published: July 2021

Background: Activating receptor-tyrosine kinase rearranged during transfection (RET) mutations and fusions have been recognized as potent drivers of oncogenesis in multiple malignancies. Recently, highly potent and selective RET inhibitors, selpercatinib and pralsetinib have been FDA approved for RET fusion+ NSCLC and selpercatinib for RET+ thyroid cancers. Here we present a comprehensive analysis of RET alterations in pan-cancer adult malignancies.

Patients and methods: 96,324 samples from 89,754 patients available from AACR Project Genie database version 8 were analyzed for the prevalence of RET fusions, mutations, and copy number alterations in diverse cancer types accessed July 21, 2020. The races of the samples within the cohort were 69,962 (72.6%) white, 5,388 (5.6%) Black, 4,909 (5.1%) Asian, 163 (0.17%) Native American, 48 (0.05%) Pacific Islander, and 15,854 (16.5%) were unknown.

Results: There were 56,382 (58.5%) samples from primary tumors, 24,204 (25.1%) samples from unspecified metastasis sites, 4,798 (5.0%) from distant organ metastasis, 1,379 (1.4%) from lymph node metastasis, 1,279 (1.3%) from local recurrence, and 8,282 (8.6%) unknown. In 96,324 tumor samples there were 2,706 (2.81%) RET alterations. This included 223 (0.23%) fusions, 1,689 RET mutations found (1.75%) in 21 tumor histologies, and 794 (0.82%) RET amplifications identified; where the most abundant tissues harboring RET fusions were NSCLC (n = 121), papillary thyroid cancer (n = 53), breast cancer (n = 8) and colorectal cancer (n = 7) and the most abundant tissues harboring RET missense mutations were NSCLC (n = 355), colorectal cancer (n = 292), melanoma (n = 236), and thyroid cancer (n = 127). NSCLC samples with RET fusions had significantly co-altered KRAS, SETD2, PVRL4, EZH1, and RRAGC.

Conclusions: RET fusions represent extremely rate events in multiple cancers. RET missense mutations occur in 2% of malignancies. Most RET missense variants are described as variants of unknown significance, limiting the impact of precision oncology for the majority of patients with RET alterations. Further functional characterization of RET variants is warranted because RET is highly targetable with therapeutics.

Citation Format: Jacob J. Adashek, Alexander Andreev-Drakhlin, Jason Roszik, Aakash P. Desai, Vivek Subbiah. The landscape of 2,706 RET alterations from 89,754 adult patients with cancer: Clinical implications [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 1221.
Abstract 1227: Oncofusion driven de novo enhancer assembly promotes malignancy in Ewing sarcomavia aberrant expression of the stereociliary protein LOXHD1
Authors: Deng Qu , Natesan Ramakrishnan , Cidre-Aranz Florencia , Arif Shehbeel , Liu Ying , Rasool Reyaz , Wang Pei , Crammer Zvi , Chou Margaret , Kumar Chandan , Weber Kristy , Eisinger Karin , Grillet Nicolas , Grünewald Thomas , Asangani Irfan
Published: July 2021

Ewing sarcoma (EwS) is a highly aggressive tumor of bone and soft tissues that mostly affects children and adolescents. The pathognomonic oncofusion EWSR1-ETS (EWS-FLI1/EWS-ERG) transcription factors drive EwS by orchestrating an oncogenic transcription program through de novo enhancers. Pharmacological targeting of these oncofusions has been challenged by unstructured prion-like domains and common DNA binding motifs in the EWSR1 and ETS, respectively. Alternatively, identification and characterization of mediators and downstream targets of EWS-FLI1 dependent or independent function could offer novel therapeutic options. By integrative analysis of thousands of transcriptomic datasets representing pan-cancer cell lines, primary cancer, metastasis, and normal tissues, we have identified a 32 gene signature (ESS32) in EwS that could stratify EwS from pan-cancer. Of the ESS32, LOXHD1 - coding for a stereociliary protein was the most exquisite gene expressed in EwS. CRISPR-Cas9 mediated deletion or silencing of EWS-FLI1 bound upstream de novo enhancer elements in EwS cells led to the loss of LOXHD1 expression and altered the EWS-FLI1, MYC, and HIF1a pathway genes, resulting in decreased proliferation and invasion in vitro and in vivo. These observations open up new avenues for developing LOXHD1-targeted small molecules or cellular therapies for this deadly disease.

Citation Format: Qu Deng, Ramakrishnan Natesan, Florencia Cidre-Aranz, Shehbeel Arif, Ying Liu, Reyaz Rasool, Pei Wang, Zvi Crammer, Margaret Chou, Chandan Kumar, Kristy Weber, Karin Eisinger, Nicolas Grillet, Thomas Grünewald, Irfan Asangani. Oncofusion driven de novo enhancer assembly promotes malignancy in Ewing sarcomavia aberrant expression of the stereociliary protein LOXHD1 [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 1227.
Abstract 1240: RRM2 and mutant p53 as therapeutic targets in TNBC
Authors: Sultana Nahid , Wilson Elizabeth A. , Elford Howard L. , Faridi Jesika S.
Published: July 2021

Triple negative breast cancer (TNBC) is a highly aggressive type of cancer associated with poor prognosis and characterized by the absence of estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor type 2 (HER2). TNBC accounts for 10 - 15% of all new cases of breast cancer. TNBC is heterogenous in nature (70% basal-like) and currently doesn't have effective targeted therapy. As such, dose-dense chemotherapeutic agents used in combination, such as doxorubicin (DOXO) with cyclophosphamide, is the regimen of choice for TNBC. However, DOXO has limited efficacy as a therapeutic agent owing to acquired drug resistance and its cardiotoxic effects. Ribonucleotide reductase (RR) is the rate limiting enzyme required for the conversion of ribonucleotide to deoxyribonucleotide in DNA synthesis during cell proliferation. Didox (3,4 dihydroxybenzohydroxamic acid) is a unique RR inhibitor with iron chelating and free radical scavenging properties. We have previously identified that ribonucleotide reductase M2 (RRM2) is upregulated in TNBC cells and is a key contributor to acquired drug resistance. We found that Didox not only inhibits RRM2, but it also reduces mutant p53 protein levels and inhibits the activation of the NF-κB pathway. Through this inhibition, we found that Didox works synergistically with DOXO to inhibit TNBC tumor growth while also minimizing DOXO-induced cardiac damage in mice. In our present study, we have observed that RRM2 expression is upregulated in TNBC patients from three independent data sets and that high RRM2 levels are associated with lower recurrence free survival (RFS) and overall survival (OS). Interestingly, high levels of RRM2 were only predictive of lower RFS and OS in patients with wild-type p53 but not mutant p53. Additionally, we have found that Didox downregulates mutant p53 protein levels in TNBC cell lines but does not alter total p53 in cells with functioning p53. Our data confirms that Didox induced downregulation of mutant p53 is not a transcriptional effect. Finally, we have identified that RRM2 protein levels increase in TNBC with progression of stage as measured in patient tissue microarray analysis. Our data presents a novel and promising approach for the treatment of TNBC that involves inhibition of RRM2, NF-kB activation, and mutant p53 that merits further clinical investigation in human models.

Citation Format: Nahid Sultana, Elizabeth A. Wilson, Howard L. Elford, Jesika S. Faridi. RRM2 and mutant p53 as therapeutic targets in TNBC [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 1240.
Abstract 1246: Anticancer activitiy of indolo[2,3-c]quinoline stabilization of the KRAS promoter G4mid structure
Authors: Psaras Alexandra Maria , Miller Jared , Tumey L. Nathan , Brooks Tracy A.
Published: July 2021

KRAS is a well validated anti-cancer therapeutic target; many active drug discovery programs are ongoing with foci on individual mutant isoforms, necessitating a wide array of drugs to be developed and missing cancers with dysregulation of non-mutant KRAS. Transcriptional down-regulation has been demonstrated to be lethal to tumor cells with aberrant KRAS signaling, irrespective of mutational status, and to potentially have a wide therapeutic window. G-quadruplex (G4) formation within KRAS's core promoter offers a molecular target to decrease the gene expression. Targeted G4-stabilization within the KRAS promoter targets cancer cells' acquired addiction to the transforming event of aberrant KRAS signaling through an activating mutation or protein overexpression, and thus is applicable to both of these deviant states. Small molecules that specifically inhibit transcriptional expression of KRAS genes have great potential for patients whose tumors have disregulated KRAS function. In the current works, compounds clarify the physiologically relevant G4 within the KRAS promoter (G4mid) through a combination of ex vivo screening, luciferase, cytotoxicity, and transcriptional regulation assays. A small set of novel indolo[2,3-c]quinoline compounds were synthesized and a newly optimized FRET Melt2 assay with a Z' score of >0.5 was used to determine KRAS G4mid stabilization efficacy and selectivity. Compounds were then examined for KRAS promoter stabilization using a luciferase assay, pancreatic and ovarian cancer cytotoxicity by an MTS assay, and correlative changes in KRAS transcription as measured by multiplexed qPCR. JM-222 is the lead indolo[2,3-c]quinoline compound that demonstrates KRAS G4mid selective stabilization and promoter regulation, cancer cell cytotoxicity and altered KRAS transcription. These works highlight the function of G4mid in regulating KRAS transcription, novel synthetic methods for indolo[2,3-c]quinoline synthesis, the improved utility of the FRET Melt2 assay, and the overall potential for small compound-mediated KRAS promoter G4 stabilization for patients harboring tumors with aberrant KRAS signaling.

Citation Format: Alexandra Maria Psaras, Jared Miller, L. Nathan Tumey, Tracy A. Brooks. Anticancer activitiy of indolo[2,3-c]quinoline stabilization of the KRAS promoter G4mid structure [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 1246.
Abstract 1268: A novel treatment approach for melanoma by dually targeting MCT1 and MCT4 lactate transporters
Authors: Sharma Sambad , Goreczny Gregory , Noonepalle Satish Kumar , Palmer Erica , Garcia-Hernandez Maria , Banerjee Daliya , Escobedo Jaime , Villagra Alejandro , Sandanayaka Vincent
Published: July 2021

Cancer cells are metabolically rewired to activate glycolysis, which results in the generation and excretion of lactate as a byproduct. Although lactate was previously thought to be a waste product of anaerobic respiration, increasing evidence has revealed that distinct cell populations within tumors use lactate as a source of energy through TCA cycle. This metabolic symbiosis between distinct cell populations, hypoxic lactate consumers, and oxidative glycolytic lactate exporters within the tumor is regulated by differential expression of lactate transporters, mainly MCT1 and MCT4. Therefore, dual targeting of MCT1 and MCT4 is a novel approach to treat cancer. We have developed a compound, NGY-B, which binds and inhibits both MCT1 and MCT4 transporters. This compound has shown to significantly increase intracellular lactate levels in melanoma models and thereby decreasing in vitro cell proliferation. When cultured in the media with exogenous lactate to mimic the tumor microenvironment, NGY-B greatly reduced lactate uptake by cancer cells. Mechanistically, NGY-B deactivated glycolytic pathway by reducing hexokinase 2 (HK2), phosphoglycerate dehydrogenase (PHGDH), and pyruvate dehydrogenase kinase 1 (PDK1) expression. Additionally, NGY-B treatment strongly decreased STAT3 and mTOR signaling pathways. Furthermore, the in vivo therapeutic efficacy of NGY-B was validated in xenograft and syngeneic mouse models of melanoma. While a significant reduction in tumor size was observed in A375 xenograft model treated with NGY-B, a robust tumor growth reduction was evident in SM1 immunocompetent syngeneic melanoma mouse model, suggesting the involvement of immune cells for higher response in this model. Supporting this premise, we also found that NGY-B treated cells showed a decrease in PD-L1, B7-H3, and B7-H4 expression. Overall, our results indicate that NGY-B inhibits melanoma by targeting metabolic symbiosis and activating antitumor immune response mechanisms.

Citation Format: Sambad Sharma, Gregory Goreczny, Satish Kumar Noonepalle, Erica Palmer, Maria Garcia-Hernandez, Daliya Banerjee, Jaime Escobedo, Alejandro Villagra, Vincent Sandanayaka. A novel treatment approach for melanoma by dually targeting MCT1 and MCT4 lactate transporters [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 1268.
Abstract 1284: P53-independent restoration of p53 pathway in tumors with mutated p53 through ATF4 transcriptional modulation
Authors: Tian Xiaobing , Ahsan Nagib , El-Deiry Wafik S.
Published: July 2021

A long-term goal in the cancer-field has been to develop strategies for treating p53-mutated tumors. A novel small-molecule, PG3-Oc, restores p53 pathway-signaling in tumor cells with mutant-p53, independently of p53/p73. PG3-Oc partially upregulates the p53-transcriptome (13.7% of public p53 target-gene dataset; 15.2% of in-house dataset) and p53-proteome (18%, HT29; 16%, HCT116-p53-/-). Bioinformatic analysis indicates critical p53-effectors of growth-arrest (p21), apoptosis (PUMA, DR5, Noxa), autophagy (DRAM1), and metastasis-suppression (NDRG1) are induced by PG3-Oc. ERK1/2- and CDK9-kinases are required to upregulate ATF4 by PG3-Oc which restores p53 transcriptomic-targets in cells without functional-p53. PG3-Oc represses MYC (ATF4-independent), and upregulates PUMA (ATF4-dependent) in mediating cell death. With largely nonoverlapping transcriptomes, induced-ATF4 restores p53 transcriptomic targets in drug-treated cells including functionally important mediators such as PUMA and DR5. Our results demonstrate novel p53-independent drug-induced molecular reprogramming involving ERK1/2, CDK9, and ATF4 to restore upregulation of p53 effector genes required for cell death and tumor suppression.

Citation Format: Xiaobing Tian, Nagib Ahsan, Wafik S. El-Deiry. P53-independent restoration of p53 pathway in tumors with mutated p53 through ATF4 transcriptional modulation [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 1284.
Abstract 1287: Novel NSAID derivatives containing selenium as potent cytotoxic agents against cancer
Authors: Ramos-Inza Sandra , Encío Ignacio , Sharma Arun K. , Sanmartín Carmen , Plano Daniel
Published: July 2021

Cancer is currently one of the major health problems of the human population and a prominent cause of death worldwide. The introduction of a selenium atom (Se) in the structure of organic molecules has demonstrated to be a valid approximation in the design of novel chemotherapeutic agents with several biological effects, including antitumoral activity. On the other hand, non-steroidal anti-inflamatory drugs (NSAIDs) have gained interest in recent years in terms of their chemopreventive and chemotherapeutic activities, whether when they are evaluated alone, as a combination therapy, or in the form of structurally modified analogs.On the basis of these findings, and taking into account the results of previous studies by our research group, we have developed a new series of twenty-five NSAID analogs bearing Se in their structure with several variations. The new compounds were tested in four cancer cell lines (HTB-54, DU-145, HT-29 and MCF-7) and two non-malignant cells (184B5 and BEAS-2B), showing promising results with IC50 values below 10 μM. The cytotoxicity of the five most potent and selective molecules was further studied in other cancer cell lines as well. Taken together, this work supports the design of new derivatives containing Se as potential antitumoral agents.

Citation Format: Sandra Ramos-Inza, Ignacio Encío, Arun K. Sharma, Carmen Sanmartín, Daniel Plano. Novel NSAID derivatives containing selenium as potent cytotoxic agents against cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 1287.
Abstract 1307: Assessment of long IVT mRNA fragments with the Fragment Analyzer system
Authors: Luttgeharm Kyle D. , Borg Solange , Pocernich Chava
Published: July 2021

Quality control analysis of long in vitro transcribed (IVT) RNAs is challenging due to the lack of commercially available kits for sizing RNA over 6,000 nt, thus, to analyze long IVT RNAs, an extended separation method was developed for the Agilent 5200 Fragment Analyzer using a commercially available RNA ladder. IVT mRNA was produced using the RiboMAX Large Scale RNA Production System (Promega). RNA transcripts 9,000 and 10,000 nt in length were diluted in nuclease-free water and separated on the Agilent 5200 Fragment Analyzer system with the Agilent RNA kit (15 nt) (p/n DNF-471) with the following modifications. The Lonza RNA marker (Lonza) (long RNA Ladder) replaced the Agilent RNA Ladder and was diluted in nuclease-free water to 96 ng/μL. The long RNA Ladder was added to the Agilent RNA Diluent Marker (15 nt) (p/n DNF-369-0004) according to the RNA kit protocol. The standard separation method (8 kV for 45 minutes) for the RNA kit (15 nt) was manually altered to the extended RNA method (4 kV for 90 minutes) in the Agilent 5200 Fragment Analyzer software for fragments greater than 6,000 nt. The extended RNA method with the long RNA Ladder was employed for all subsequent runs. The long RNA Ladder separated with the extended method displayed enhanced resolution compared to separation with the standard method as seen by the increased spacing between the ladder peaks and the increased sharpness of the 9,000 nt peak. The extended RNA method reported a lower average sizing percent error (-0.7 %) over the entire concentration range of the kit compared to the standard RNA method (8.4 %) for the 9,000 nt sample. The 10,000 nt IVT mRNA average percent sizing error was similar between the two separation methods throughout the dilution series. Using the extended method, the 9,000 and 10,000 nt IVT mRNA samples were successfully analyzed with good sizing precision and accuracy, demonstrating that a commercially available RNA ladder can be used with the Fragment Analyzer system to provide accurate sizing of large IVT mRNA samples. The extended RNA method is recommended when extremely accurate sizing or high resolution is needed for determining the presence of degradation or sizing differences from incomplete transcription in IVT mRNA samples longer than 6,000 nt. For Research Use Only. Not for use in diagnostic procedures.

Citation Format: Kyle D. Luttgeharm, Solange Borg, Chava Pocernich. Assessment of long IVT mRNA fragments with the Fragment Analyzer system [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 1307.
Abstract 1312: Anticancer activity of CA102N in breast cancer cells in vitro and in vivo
Authors: Tchaparian Eskouhie , Lin Louis , Wang Ann
Published: July 2021

CA102N is a novel anticancer product designed to deliver its payload (Nim) to cells via the CD44 receptor. CA102N is currently in Phase 1 clinical trial for the treatment of metastatic colorectal cancer (mCRC). The major target of CA102N is the PI3K/Akt/mTOR cell signaling pathway, one of the most significantly deregulated pathway in several human cancers, including breast cancer. In the present study, the anticancer activity of CA102N was assessed on cell signaling, cell proliferation, and apoptosis in vitro in MDA-MB-231 human breast cancer cells. The antitumor efficacy was also tested in vivo in xenograft mice. We demonstrated that CA102N selectively inhibited MDA-MB-231 breast cancer cell growth and proliferation in vitro Administration of CA102N at 4.6mg/kg in xenograft mice resulted in effective tumor growth inhibition (TGI, 80%) with no apparent treatment-related toxicity. Suppression of PI3K/Akt downstream signaling was also detected in vitro. These results suggest that CA102N may represent a new potential treatment option for breast cancer. Combinations therapies and schedules are currently being explored in mice. to maximize the basis for its advancement therapy into the clinic.

Citation Format: Eskouhie Tchaparian, Louis Lin, Ann Wang. Anticancer activity of CA102N in breast cancer cells in vitro and in vivo [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 1312.
Abstract 1313: TH1902, a docetaxel peptide-drug conjugate, shows pre-clinical efficacy in several Sortilin-positive (SORT1+) cancers
Authors: Marsolais Christian , Currie Jean-Christophe , Demeule Michel , Charfi Cyndia , Larocque Alain , Zgheib Alain , Béliveau Richard , Annabi Borhane
Published: July 2021

One strategy to achieve greater selectivity of anticancer drug to cancer cells is the conjugation of cytotoxic agents to peptide ligands that selectively target receptors abundantly expressed in these tumor cells. Recently, increased expression of sortilin (SORT1), a scavenging receptor, has been observed in various cancers including breast, ovarian, endometrial, skin, colorectal and pancreatic cancers. In light of these SORT1 levels, we developed a peptide conjugation platform to target SORT1 and to increase cell selectivity and internalization of anticancer agents. Docetaxel was conjugated to a sortilin-binding proprietary peptide (TH19P01). High in vitro intracellular internalization of TH19P01 in TNBC cells was first confirmed and was reduced when SORT1 expression was silenced using siRNA or upon competition with the SORT1 ligands neurotensin and progranulin. Significant in vitro intracellular delivery of the docetaxel-TH19P01 conjugate (TH1902) was observed in SORT1+ cancer cell lines while maintaining efficient docetaxel cytotoxic mechanism. TH1902 further exerted potent anti-proliferative and anti-migratory activities when tested on TNBC-derived MDA-MB-231 cells. TH1902 also triggered faster and more potent apoptotic cell death than did docetaxel. Pre-clinical in vivo studies were performed in human SORT1+ tumor xenografts grown in mice including TNBC (MDA-MB-231 and HCC-70), melanoma (SK-MEL-28), colorectal (HT-29) and pancreatic (PANC-1) cancer models. Mice were treated with either TH1902 or docetaxel by IV bolus injections at equivalent doses of docetaxel (MTD or ¼ MTD). In all cases, TH1902 showed more potent inhibition than Docetaxel. These results strongly support future clinical development of TH1902 as novel therapeutics in SORT1+ cancers.

Citation Format: Christian Marsolais, Jean-Christophe Currie, Michel Demeule, Cyndia Charfi, Alain Larocque, Alain Zgheib, Richard Béliveau, Borhane Annabi. TH1902, a docetaxel peptide-drug conjugate, shows pre-clinical efficacy in several Sortilin-positive (SORT1+) cancers [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 1313.
Abstract 1318: Mechanochemical dynamic therapy for focal cancer treatment
Authors: Kim Gun , Wu Qiong , Chu James L. , Smith Emily J. , Oelze Michael L. , Li King C. , Moore Jeffrey S.
Published: July 2021

This study proposes a new cancer drug delivery modality that allows for spatiotemporal control over activation of the therapeutic. Current standard cancer therapies of surgery, chemotherapy, and radiation therapy have their limitations, such as invasiveness and systemic toxicities. Developing a new modality that is localized and triggerable is becoming increasingly advantageous. Currently, photodynamic therapy (PDT) has been shown to be clinically effective but is limited by poor tissue penetration of light. Sonodynamic therapy (SDT) bypasses this pitfall with increased tissue penetration depth of ultrasound. However, PDT has limitations as it relies on the potentially damaging ultrasound cavitation effect and requires sonosensitizers or nanoparticles that have issues with bioavailability, biostability, and biosafety. In this study, we propose a novel ultrasound-based cancer treatment modality called mechanochemical dynamic therapy (MDT). In MDT, high intensity focused ultrasound (HIFU) delivers mechanical forces to force-responsive moieties of azo mechanophores that are embedded into biocompatible polyethylene glycol (PEG) hydrogel polymers. Upon focal sonication with HIFU, these mechanophores generate highly reactive free radicals (FRs) that are converted to reactive oxygen species (ROSs). The sonicated gels are then placed into in vitro cultures, allowing for the diffusion of ROSs into the cells to induce oxidative cytotoxicity and eventually cell death. Cell proliferation is monitored at 24-hour intervals, and by 72 hours, the sonicated gels produced cell killing effects comparable to lethal doses of H2O2 in both in vitro mouse melanoma (B16F10) and breast cancer (E0771) models. Sonication of control hydrogels that did not contain mechanophores showed minimal cytotoxicity. This study shows the potential of MDT as a drug delivery platform that overcomes the limitations of PDT and SDT and has the potential to be applied synergistically with other current cancer treatments. This is the first demonstration of using HIFU-activated mechanophores to non-invasively deliver cancer therapies with spatiotemporal control.

Citation Format: Gun Kim, Qiong Wu, James L. Chu, Emily J. Smith, Michael L. Oelze, King C. Li, Jeffrey S. Moore. Mechanochemical dynamic therapy for focal cancer treatment [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 1318.
Abstract 1319: Rapid accumulation of cytotoxic payload in tumor tissue drives BT5528 activity in tumor models
Authors: Lahdenranta Johanna , Bennett Gavin , Huxley Philip , Mudd Gemma , Upadhyaya Punit , Jeffrey Phil , Keen Nicholas
Published: July 2021

BT5528 was developed as a Bicycle® toxin conjugate to deliver monomethyl auristatin E (MMAE) -payload to EphA2 overexpressing tumors. It consists of a bicyclic peptide targeting the tumor antigen EphA2, linked to the cytotoxin MMAE via a molecular spacer and cleavable linker. Administration of BT5528 results in rapid uptake of payload into EphA2 overexpressing xenograft tumors associated with persistent toxin levels in tumor tissue and limited systemic exposure of both parent drug and payload (1). BT5528 showed a favorable preclinical profile supporting the initiation of a first-in-human Phase I/II study (NCT04180371) to investigate safety and efficacy of BT5528 in indications with evidence of EphA2 expression including non-small-cell lung cancer (NSCLC), ovarian cancer, triple-negative breast cancer (TNBC), gastric/upper gastrointestinal (GI), pancreatic and urothelial cancers (2). We have used EphA2 overexpressing tumor xenograft models in both mice and rats to elucidate the relative differences between toxin payload delivery and systemic exposure of BT5528. Comparison of payload-delivery and systemic exposure from EphA2 -targeted Bicycle toxin conjugate and antibody-drug conjugate (ADC) demonstrate the differentiation of these toxin-payload delivery platforms. ADC payload delivery depends upon a sustained plateau-like pharmacokinetic (PK) profile that exposes target and potentially nontarget organs to intact ADC for several days. In contrast, BT5528 achieves prolonged toxin delivery to tumors, following transient exposure in plasma of less than one hour. A Phase I/II study of BT5528 in patients with solid tumors is ongoing, which will investigate if this PK novel, differentiated pharmacokinetic profile, unique to Bicycle toxin conjugates, gives rise to a favorable balance of efficacy and safety. References: 1. Bennett et al. Mol. Cancer Ther. 2020;19:1385-942. 2. Bendell et al. TPS3655 Journal of Clinical Oncology 38, no. 15_suppl

Citation Format: Johanna Lahdenranta, Gavin Bennett, Philip Huxley, Gemma Mudd, Punit Upadhyaya, Phil Jeffrey, Nicholas Keen. Rapid accumulation of cytotoxic payload in tumor tissue drives BT5528 activity in tumor models [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 1319.
Abstract 1322: Evaluating intracellular accumulation profiles of chemotherapeutic agents using CLENs for the treatment of Y79 retinoblastoma
Authors: Luo Nan , Patel Virali , Patel Minesh , Conte Eric , Campbell Robert
Published: July 2021

Retinoblastoma is the most common intraocular malignancy in children, with approximately 200-300 new cases in the United States each year. Currently, conventional chemotherapy agents (carboplatin, cisplatin, doxorubicin, vincristine, and cyclophosphamide) used to treat retinoblastoma, are rapidly eliminated from circulation. Novel lipid nanoparticles (LNP) have been shown to improve delivery of encapsulated chemotherapeutic agents to Y79 retinoblastoma cells, and therefore the agents are less toxic to healthy cells. Past studies have supported the use of LNP delivery systems to enhance chemotherapeutic drug action against Y79 retinoblastoma cells as well. The experimental plan will now evaluate the use of cellular membrane lipid-extracted nanoliposomes (CLENs) to examine targeting using cellular models of retinoblastoma. Y79 cells were cultured in RPMI growth medium supplemented by 20% FBS. CLENs and lipid extracts (LE) were prepared according to previously published protocols. Following the development of Y79-LE nano-preparations consisting of DOPC, Y79-LE, and cholesterol at different ratios, preparations were evaluated in terms of physicochemical properties and uptake by Y79 cells. The additional inclusion of cationic lipid DOTAP in Y79-LE preparations was evaluated for select preparations. Particle sizes and zeta potential values were determined for each preparation type by ZetaPALS. CLENs exhibited an average particle size between 400 to 600 nm. Experiments with Y79-CLENs prepared in the absence and presence of DOTAP, showed they were taken up by the target cell population. In general, the inclusion of Y79-LE increased cellular uptake. The inclusion of cholesterol in combination with DOTAP showed enhanced liposomal uptake in Y79 retinoblastoma cells. Evidence from previous studies suggest a benefit of using lipid nanoparticles compared to more conventional treatment options. Preliminary findings suggest a positive correlation between the particle size and degree of cellular uptake. Additional optimization studies are currently underway.

Citation Format: Nan Luo, Virali Patel, Minesh Patel, Eric Conte, Robert Campbell. Evaluating intracellular accumulation profiles of chemotherapeutic agents using CLENs for the treatment of Y79 retinoblastoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 1322.
Abstract 1323: Novel autophagy inhibitor to treat pancreatic cancer
Authors: Ramachandran Mythili , Ma Zhao , Li Yuanpei
Published: July 2021

In this study, we develop a novel autophagy inhibitor targeting one of the most aggressive cell populations present in pancreatic tumors, the pancreatic cancer stem cell (CSC). Targeting this population which has the malignant properties of tumorigenesis/tumor recurrence, the ability to differentiate into a heterogenous tumor cell types and can self-renew is a new strategy to alleviate the current dismal 10% five-year survival rate of pancreatic cancer. Here we characterize an autophagy inhibitor which is a first-in-class nanoparticle comprised of a chloroquine-derived small molecule drug that can self-assemble into a micelle. Due to its favorable pharmacokinetic properties and the CSC reliance on autophagy, our compound is able to selectively target this cell population both in vitro and in vivo. Additionally, the compound has shown synergy with the current standard of care chemotherapeutic, gemcitabine, with an 88.9% reduction in tumor volume in the combination of the two drugs compared to gemcitabine treated alone (p<0.0001) in two separate treatment regimens using a pancreatic PDX mouse model. We further illustrate that the stem cell population is targeted by inhibiting tumorsphere formation in established pancreatic cancer cell lines MIA-PaCa2 and PANC-1 and in pancreatic PDX-derived CSCs in vitro. The drug treatment also promotes a decrease in pluripotency markers, particularly in Sox2 levels. Finally, the drug is well-tolerated with a maximum tolerated dose above 100 mg/kg in mice and is orally bioavailable.

Citation Format: Mythili Ramachandran, Zhao Ma, Yuanpei Li. Novel autophagy inhibitor to treat pancreatic cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 1323.