bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 2700: ORM-6151: A first-in-class CD33-antibody enabled GSPT1 degrader for AML
Authors: Palacino James , Lee Pedro , Jeong Hangyeol , Kim Yeonjoon , Song Yoojin , Permpoon Uttapol , Wong Wesley , Bai Chen , Fishkin Nathan , Takouri Khuloud , Yu Eunjun , Yi Yong , Skaletskaya Anna , Kim Min-Soo , Kim Da-Yeong , Choi Dong-Ki , Park Peter U.
Published: April 2023

Targeted protein degraders (TPDs) have expanded the breadth of therapeutic options through both their catalytic mechanism of action and ability to degrade previously “undruggable” target proteins. Prior reports of small-molecule GSPT1 degraders such as CC-90009 in AML demonstrate potent anti-tumor cytotoxicity, but with a potentially narrow therapeutic index. To increase the efficacy vs. tolerability window of TPDs and improve drug delivery, we introduce TPD-Squared (TPD2 TM), a dual-targeted protein degradation approach of combining the catalytic mechanism of targeted protein degradation with the precision of tumor-targeting therapeutic antibodies. We have previously shown in vitro and in vivo efficacy with a HER2-targeted TPD2 conjugate: ORM-5029. Following on that success, we generated conjugates using a CD33-targeting antibody (OR000283) produced by engineering the FAb (H&L) sequences from gemtuzumab onto an IgG1 Fc with N297A variant to inhibit Fc-γR binding. Medicinal chemistry optimization of linker-payloads led to the identification of ORM-6151, which is composed of SMol006, a highly potent GSPT1 degrader conjugated to OR000283 via a novel β-glucuronide releasable linker. ORM-6151 treatment in CD33-expressing cell lines showed picomolar activity with 10-1000-fold greater potency compared to several GSPT1 degrader molecules, including CC-90009 or Mylotarg, and had robust activity in Mylotarg-resistant lines (AML193 and Kasumi6). ORM-6151 also exhibited picomolar potency in in vitro cytotoxicity to primary relapsed/refractory AML patient blasts, with better potency than CC-90009 and Mylotarg. We evaluated ORM-6151 in several in vivo disseminated xenograft models and observed robust efficacy following a single treatment at doses as low as 0.1 mg/kg. Tumor growth inhibition correlated with the degree and duration of GSPT1 depletion and changes in the expression of previously described integrated stress response biomarker genes. In summary, ORM-6151 is a promising, potential therapy for AML and currently in preclinical development as a first-in-class targeted protein degrader therapy with CD33-targeted delivery.

Citation Format: James Palacino, Pedro Lee, Hangyeol Jeong, Yeonjoon Kim, Yoojin Song, Uttapol Permpoon, Wesley Wong, Chen Bai, Nathan Fishkin, Khuloud Takouri, Eunjun Yu, Yong Yi, Anna Skaletskaya, Min-Soo Kim, Da-Yeong Kim, Dong-Ki Choi, Peter U. Park. ORM-6151: A first-in-class CD33-antibody enabled GSPT1 degrader for AML [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 2700.
Abstract 2766: Automation of linear range determination: Enzymatic progress curve applications
Authors: May Earl William , Urul Daniel , Cornell-Kennon Susan , Lu Zhibing , Schaefer Erik , Hoare Sam , Laliberté France , Vong Quay , Payette Paul , Marois Jean
Published: April 2023

To characterize modulators of enzymatic activity, a continuous assay format will quantify with confidence the initial reaction velocity far better than an end point assay. When the progress curve is linear from the start and remains linear throughout the experiment, a single end point reading can approximate the reaction rate, but a kinetic assay will provide the rate more accurately. However, if there is a delay in the onset of the reaction, or there are other changes in reaction rate over time, then a single end point reading is insufficient. Thus, important information about the reaction can be missed or mischaracterized. While visual inspection is the most common way to determine the range of the progress curve from which to extract rate information, this method is not practical when thousands of progress curves are generated in an experimental day. We have developed an automated protocol to streamline and optimize the process. The heuristic algorithm analyzes the progress curve to identify different regions for characterization (e.g. lag, primary rate, secondary rate, final plateau) and then extract rates of interest for each of these regions. These rates are subsequently used to measure the specific activity of the enzyme under various assay conditions, and to characterize the modulation of that activity: simple dose-response testing, mode of inhibition analysis, time-dependent inhibition determination, reversibility testing, determination of residence time for reversible inhibitors, and kinact/KI analysis for irreversible inhibitors. We describe the algorithm and several applications as they apply to protein kinases using the PhosphoSens assay platform from AssayQuant within the Analyze module of the Scigilian data analysis package.

Citation Format: Earl William May, Daniel Urul, Susan Cornell-Kennon, Zhibing Lu, Erik Schaefer, Sam Hoare, France Laliberté, Quay Vong, Paul Payette, Jean Marois. Automation of linear range determination: Enzymatic progress curve applications [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 2766.
Abstract 2786: Targeting oncogene and inflammation for cancer therapy
Authors: Wang Wei , Datta Sayantap , Velu Sadanandan E. , Luo Ming , Zhang Ruiwen
Published: April 2023

Accumulating evidence has demonstrated that the overexpression of and the loss of tumor suppressor genes contribute to the aggressiveness, poor prognosis, and poor response to treatment associated with advanced cancer. Overexpression and activation of the MDM2 and NFAT1 oncogenes frequently occur in human cancer and is associated with invasive and high grade/late-stage tumors, metastasis, and recurrence, and are negative prognostic factors for cancer patients. Dual targeting MDM2 and NFAT1 represents a novel molecular target for the treatment of cancer. However, most of the current MDM2 inhibitors have been designed to block the binding between MDM2 and p53, and have limited efficacy against tumors with mutant or deficient p53. Considering that high incidence of TP53 mutations and MDM2 overexpression in tumors, these MDM2 SMIs are expected to have low or no efficacy against those types of cancer. Therefore, there is an urgent need to identify a novel, p53-independent strategy to inhibit MDM2, in order to affirm the therapeutic value of targeting MDM2. In addition, as an important inflammatory factor, there are no specific NFAT1 inhibitors developed for cancer therapy. By employing crystallization screening, NMR-based screening, and high-throughput virtual and cell-based screening assays, we discovered a class of makaluvamine analogs with the desired property. One of these analogs, MA242, was identified as a potent and selective MDM2 and NFAT1 inhibitor. Its in vitro and in vivo anti-breast cancer activities and underlying mechanisms of action were evaluated in breast cancer cell lines with various p53 backgrounds. Our results demonstrated that MA242 directly bound to MDM2 and NFAT1 protein with high affinity and induced its protein degradation. As a result of this binding, MA242 decreased cell proliferation, and induced apoptosis and G2/M phase arrest in breast cancer cell lines, regardless of the p53 status. Furthermore, MA242 inhibited the tumor growth and metastasis in orthotopic and patient-derived xenograft (PDX) models, without any host toxicity. Single-cell sequencing results provided the molecular and cellular crosstalk between cancer and immune system, and identified the predictive biomarkers of response after the treatment. In conclusion, MA242 is a potent and selective MDM2 and NFAT1 dual inhibitor with distinct mechanisms of action compared to the existing inhibitors. Our data suggest that the dual targeting oncogene and inflammation is a promising strategy for the treatment of human cancer. (Supported by NIH R01CA214019 and a UH DDI Seed Grant.)

Citation Format: Wei Wang, Sayantap Datta, Sadanandan E. Velu, Ming Luo, Ruiwen Zhang. Targeting oncogene and inflammation for cancer therapy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 2786.
Abstract 2796: Tumor pharmacokinetics, pharmacodynamics and efficacy analysis of WEE1 inhibitor, zn-c3 in patient-derived xenograft models of glioblastoma
Authors: Mehta Shwetal , Tien An-Chi , Patel Sonam , Margaryan Tigran , Shivanna Anilkumar Thaghalli , Elena Leonel , Molloy Jennifer , Knight William , Hon Ruiheng , Elliott Mackenna , Stavnichuk Mariya , Opachich Zorana , Chang Yu-Wei , Montgomery Chelsea , Himes Sarah , Hopkins Barbara , Tovmasyan Artak , Sanai Nader
Published: April 2023

WEE1 kinase regulates G2/M checkpoint transition via phosphorylation of CDK1 and prevents entry into mitosis. WEE1 inhibition increases genomic instability due to G2/M checkpoint inactivation and can result in mitotic catastrophe as monotherapy or when combined with DNA damaging agents. In this study, we evaluated the efficacy as well as pharmacokinetic and pharmacodynamic properties of ZN-c3, a best-in-class WEE1 inhibitor, in orthotopic patient-derived xenograft (PDX) models of GBM. Mice with intracranial tumors were randomized to 80 mg/kg ZN-c3 PO QD x 2 weeks vs. placebo. ZN-c3 levels in plasma and contrast-enhancing tumor tissue were measured by liquid chromatography tandem mass spectrometry (LC-MS/MS). Unbound fractions were determined by equilibrium dialysis. Immunohistochemistry was performed to assess levels of pCDK1, phospho-Histone H3 (pHH3), and cleaved caspase 3 (CC3). The median unbound concentrations of ZN-c3 were 315 nmol/L and 15 nmol/kg in plasma and tumor tissue, respectively - higher than the biochemical IC50 of ZN-c3 for inhibition of WEE1 (3.8nM). An increase in pHH3(+) cells (0.40% vs. 6.57%, p=0.03) indicated drug-induced mitotic entry upon ZN-c3 treatment. ZN-c3 was potently cytotoxic across multiple patient-derived xenograft (PDX)-derived cell lines (IC50- 150-10000nM). Time and dose-escalation experiments exhibited target engagement at concentrations lower than IC50 values within one hour of treatment. Basal levels of WEE1 and pCDK1 were correlated with cell viability in response to ZN-c3 across multiple PDX cell lines. Overall, ZN-c3 is well tolerated, achieves pharmacologically-relevant unbound concentrations in GBM PDX models, and is associated with significant checkpoint modulation. Preclinical evaluation of ZN-c3 in combination with radiation therapy and DNA damage response pathway inhibitors is currently underway, which will support future combinatorial strategy for glioblastoma treatment.

Citation Format: Shwetal Mehta, An-Chi Tien, Sonam Patel, Tigran Margaryan, Anilkumar Thaghalli Shivanna, Leonel Elena, Jennifer Molloy, William Knight, Ruiheng Hon, Mackenna Elliott, Mariya Stavnichuk, Zorana Opachich, Yu-Wei Chang, Chelsea Montgomery, Sarah Himes, Barbara Hopkins, Artak Tovmasyan, Nader Sanai. Tumor pharmacokinetics, pharmacodynamics and efficacy analysis of WEE1 inhibitor, zn-c3 in patient-derived xenograft models of glioblastoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 2796.
Abstract 2804: 3D printing of perfusable alveolar model for efficacy evaluation of polyisoprenylated cysteinyl amide inhibitors on lung cancer cells
Authors: Romero Diana Isabel , Ren Bing , Leon Christopher , Offringa Ite A. , Lamango Nazarius S. , Huang Yong
Published: April 2023

Lung cancer is the leading cause of cancer death in the United States, and Black Americans are being disproportionality affected. Lung adenocarcinoma (LUAD) is the most common histological lung cancer subtype among all lung cancer patients, including black patients. There is still no available physiologically relevant three-dimensional (3D) in vitro model that can be used to study the treatment efficacy on LUAD cells, in particular, those from Black patients. In this study, we aim to develop a 3D alveolar model with a perfusable epithelialized channel using 3D biofabrication technologies. We will apply the model to test their efficacies of polyisoprenylated cysteinyl amide inhibitors (PCAIs) and other drugs on LUAD. First, a perfusable channel is constructed within a gelatin composite extracellular matrix (ECM) using a sacrificial material-assisted 3D embedded printing technology. Next, the channel is seeded with KRAS-mutated NCI-H23 LUAD (derived from a Black patient) or hAEC-C7 (untransformed, immortalized human alveolar epithelial cells) respectively, and exposed to drugs to test the anti-cancer efficacy. In particular, PCAIs, which are potential therapeutics targeting activated KRAS, are investigated for their cytotoxicity on H23 LUAD and hAEC-C7 cells for comparison. Compared to two-dimensional (2D) models, the proposed 3D alveolar model can offer a more physiologically relevant 3D cell-to-ECM environment to test LUAD therapeutics. The use of H23 cells and, in the future, other LUAD cells from Black patients ensures that any developed drugs constitute valid treatment options for black patients with RAS-mutated pathways, thus minimizing health disparities.

Citation Format: Diana Isabel Romero, Bing Ren, Christopher Leon, Ite A. Offringa, Nazarius S. Lamango, Yong Huang. 3D printing of perfusable alveolar model for efficacy evaluation of polyisoprenylated cysteinyl amide inhibitors on lung cancer cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 2804.
Abstract 2833: Exploring the impact of IL-17 pathway modification on radiation dermatitis and radiation therapy efficacy
Authors: Pirtle Megan E. , Kost Yana , Deutsch Alana , Shinoda Kosaku , McLellan Beth N.
Published: April 2023

Here we explore the role of Interleukin-17 (IL-17) in the promotion of radiation dermatitis (RD) and radiation therapy (RT) efficacy. RD is a common and potentially treatment-limiting skin toxicity that occurs following RT. When the treated tumor is close to the skin, as in head and neck or breast cancer, RD is the most common acute adverse event which negatively impacts patients’ quality of life; however, evidence-based treatments are limited. We performed RNA sequencing of RT-treated skin in both human skin and a murine model, which each showed increased expression of IL-17 Receptor type C (IL-17RC). To further explore the role of the IL-17 pathway in the development of RD, both genetic knockout of IL-17RC and pharmacologic blocking of IL-17A in mouse models were studied, and both were found to have attenuated histopathological signs of RD, including inflammation, acanthosis, and fibrosis when compared to controls. After establishing the importance of the IL-17 pathway on RD, we explored the impact of such IL-17 pathway modification on the anti-tumorigenic efficacy of RT, an important step when considering a future IL-17 neutralizing therapy for RD. A Trans-PyMT murine model of triple-negative breast cancer was used to evaluate the impact of IL-17A neutralization on RT efficacy. There was no difference found in the efficacy of RT in mice treated with IL-17A neutralizing antibody as compared with saline control. Overall, we present a clinically relevant murine model which advances our understanding of the immunopathogenesis of RD and suggests further exploration of targeted therapies for RD prophylaxis is warranted. Additionally, we show that modifying the IL-17 pathway is effective in mitigating RD phenotype with no impact on RT efficacy.

Citation Format: Megan E. Pirtle, Yana Kost, Alana Deutsch, Kosaku Shinoda, Beth N. McLellan. Exploring the impact of IL-17 pathway modification on radiation dermatitis and radiation therapy efficacy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 2833.
Abstract 2845: PpIX synthesis increases PDT resistant cells due to the modulating effect of EGCG on the heme synthesis pathway
Authors: León Daniela , Gutiérrez Álvaro , Weber Helga , Silva Ramón , Reyes María Elena , Viscarra Tamara , Buchegger Kurt , Ili Carmen , Brebi Priscilla
Published: April 2023

Introduction: Photodynamic therapy (PDT) is a treatment for non melanoma skin cancer. PDT kills cells through reactive oxygen species (ROS), produced by interaction between cellular O2 and an excited photosensitizer (PS) by a specific light. One of the most used PS in dermatology is Protoporphyrin IX (PpIX) and its precursor methyl aminolevulinate (MAL). MAL enters into cells and is converted to PpIX by enzymes of the heme group synthesis pathway. The insertion of ferrous iron into PpIX forms a heme molecule, which has no PS action. A previous study shows that efficacy of PDT, in resistant cells, can be improved by addition of epigallocatechin gallate (EGCG), a green tea polyphenol. Therefore, the aim of this work is to evaluate the rol of EGCG on PPIX synthesis.

Material and methods: It was used a A-431 cell line from skin squamous cell carcinoma. The EC50 of EGCG was determined by MTT assay after 24 hours. Clonogenic assay was carried out using EGCG 10, 20 and 40 μM, for 4 and 24 hours of incubation. To evaluate PpIX and ROS, A-431 cells were exposed to EGCG (10, 20, 40 μM) with or without MAL 2 mM. After 4 hours, some plates were irradiated with red light to generate ROS. PpIX and ROS were detected by flow cytometry. Gene expression of enzymes of heme synthesis was analyzed by RT-qPCR. Intracellular iron was measured using a commercial kit. ﻿

Results: EC50 determined a concentration of 50 μM of EGCG at 24 hours. EGCG concentrations from 10 μM reduced cell clonogenic capacity, even with only 4 hours of incubation. A-431 cells show PDT resistance with MAL 2 mM and a fluence of 4 J/cm2. The addition of EGCG to MAL-PDT showed a decrement of cell viability with an increase of PpIX and ROS. Besides, incubation with EGCG for 4 hours, triggered an increment of HMBS enzyme and decrease of FECH. In addition, EGCG reduced intracellular iron concentrations.

Conclusion: These findings show that EGCG has a PDT enhancing effect, decreasing intracellular iron levels and modulating gene expression of heme synthesis enzymes, which are directly related with high levels of PpIX production and ROS levels, causing the death of resistant cells.Acknowledgements: Postdoctoral FONDECYT Nº 3210618, IDeA I+D FONDEF ID21I10027

Citation Format: Daniela León, Álvaro Gutiérrez, Helga Weber, Ramón Silva, María Elena Reyes, Tamara Viscarra, Kurt Buchegger, Carmen Ili, Priscilla Brebi. PpIX synthesis increases PDT resistant cells due to the modulating effect of EGCG on the heme synthesis pathway [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 2845.
Abstract 2875: Evidence of immunosuppression in patients with breast ductal carcinoma in situ
Authors: Taghinezhad-S Sedigheh , Mohseni Amir Hossein , Beatty Pamela L. , Emens Leisha A. , Finn Olivera J.
Published: April 2023

Introduction: Ductal carcinoma in situ (DCIS) is a noninvasive precursor to invasive breast cancer. Although not all DCISlesions progress to cancer, most DCIS are treated as early breast cancer, given the uncertainty of which lesions will progress. The current increase in the incidence of DCIS has sparked interest in the immune contexture of the DCIS lesions as well as the immune status of DCIS patients, as a means to predict which DCIS lesions will progress to cancer. Studies done so far in invasive breast cancer showed that the immune system can mediate both tumor-promoting influence (via T regulatory (Treg) cells, M2 macrophages, myeloid-derived suppressor cells (MDSCs)), as well as tumor-suppressing influences (via CD8+ and CD4+ effector T cells, natural killer cells (NK), M1 macrophages, tissue-resident memory T (Trm) cells, B cell and dendritic (DCs) cells). Similar studies are still lacking in DCIS. Our aim was to start closing the gap in our understanding of the DCIS immune microenvironment, which will pave the way for novel preventative and therapeutic strategy.

Methods: We analyzed by flow cytometry peripheral blood mononuclear cells (PBMCs) from newly diagnosed DCIS patients for the presence of various immune cell types expressing specific phenotypic markers of immune effectors or immune suppressors and compared them with PBMC from age-matched healthy individuals.

Results: We found a statistically significant increase in the frequency of FoxP3+ regulatory T cells in DCIS PBMC compared with healthy controls. There was also a significant increase in Tim-3+CD8+ T effector memory cells (P= 0.035) and Tim-3+ CD8+ NKT cells (P = 0.033) in the PBMCs of patients with DCIS compared with healthy controls. T cells expressing other exhaustion markers, such as PD-1+ and LAG-3+ were present at very low levels in both groups.

Conclusion: Our results suggest that some of the many immunosuppressive mechanisms seen in patients with invasive breast cancer, such as regulatory T cells, are already present in pre-cancer DCIS. Evidence of the beginning of immune suppression is also reflected in the increased frequency of CD4+ and CD8+ T cells expressing the exhaustion marker Tim-3.

Citation Format: Sedigheh Taghinezhad-S, Amir Hossein Mohseni, Pamela L. Beatty, Leisha A. Emens, Olivera J. Finn. Evidence of immunosuppression in patients with breast ductal carcinoma in situ [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 2875.
Abstract 3068: CREBBP/EP300 disruption promotes tumor progression and confers synthetic lethality in anaplastic thyroid cancers
Authors: Haase Jacob , Gebhard Talia A. , Liu Qi , Bernabé Sara G. , Hao Jingzhu , Unegbu Chisom , Bikas Athanasios , Qi Jun , Landa Iñigo
Published: April 2023

Anaplastic thyroid cancers (ATC) are fast-growing, undifferentiated tumors and almost invariably fatal, primarily due to the lack of effective therapeutic options. The recent approval of dabrafenib plus trametinib for the treatment of BRAFV600E-mutant ATCs improved the prognosis of a subset of patients, but ineligibility and acquired resistance still limit their use. Overall, ATC patients remain in great need of tailored therapeutic options. We previously showed that loss-of-function alterations targeting histone acetyltransferase (HAT) genes, namely CREBBP and EP300, occur in 15-20% of ATCs, but only in <1% of their well-differentiated counterparts. What remains unknown are the specific mechanisms by which HAT disruptions perturb chromatin architecture, impact gene homeostasis, and unleash cellular processes in these aggressive tumors. We are assessing the HAT-mediated thyroid cancer progression. CREBBP/EP300 knockouts enhanced thyroid cancer cell proliferation in vitro and induced thyroid gland growth in a thyroid-specific mouse model of HAT loss. We are leveraging these animals to characterize the in vivo effects of Crebbp/Ep300 knockout, alone or in combination with BrafV600E, in thyroid cancer phenotypes and epigenetic reconfiguration. In addition, we are exploiting the molecular consequences of HAT loss to explore tailored treatments. CRISPR/Cas9 screens identified a mutual CREBBP/EP300-dependency of HAT-mutant human cancer cell models. Our experiments in thyroid cancer cells employing CREBBP/EP300-targeting proteolysis-targeting chimera (PROTAC) compounds specifically degraded these proteins and decreased histone acetylation. Our findings prove the oncogenicity of HAT loss in thyroid cancer progression and support exploring synthetic lethality dependencies in CREBBP/EP300-mutant ATCs. In summary, we provide pre-clinical basis to inform genomics-driven and mechanism-oriented decisions for the clinical management of patients with HAT-altered ATC.

Citation Format: Jacob Haase, Talia A. Gebhard, Qi Liu, Sara G. Bernabé, Jingzhu Hao, Chisom Unegbu, Athanasios Bikas, Jun Qi, Iñigo Landa. CREBBP/EP300 disruption promotes tumor progression and confers synthetic lethality in anaplastic thyroid cancers [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 3068.
Abstract 3070: Leveraging oxysterol sulfation by SULT2B1b sulfotransferase and liver X receptor inactivation to suppress advanced prostate cancer
Authors: Park Bobae , Knapczyk-Stwora Katarzyna , Liu Yaguang , Song Chung S. , Chatterjee Bandana
Published: April 2023

Advanced prostate cancer is a heterogeneous disease driven by diverse genetic alterations, with metastasis and lethal progression as the inevitable outcome. We observed that a subset of clinical primary prostate cancer is markedly reduced for SULT2B1b (SULT2B) sulfotransferase, which is an oxysterol-sulfating enzyme. Metastasized castration-resistant prostate cancer (CRPC) uniformly lacks SULT2B. Oxysterols are oxidized cholesterol metabolites and in agonist function, they activate liver X receptors (LXRα/β), which are members of the nuclear receptor family and regulators of lipogenesis, cholesterol homeostasis and immune functions. LXR signaling is enzymatically inhibited by SULT2B activity since sulfated oxysterols are LXR-inert. We previously reported that genetic silencing of SULT2B led to escalated CRPC proliferation; enhanced xenograft tumor growth; increased cell migration, invasion; reduced stiffness, adhesiveness; and EMT activation. SULT2B-depleted CRPC cells showed robust upregulation of AKR1C3 aldo-keto reductase and AKR1C3-dependent activation of the ERK1/2 survival signal. AKR1C3 regulates intratumoral androgen biosynthesis, and it is known to be elevated in advanced prostate cancer. In the current study, we validate our previous result by showing that ectopic expression of SULT2B caused AKR1C3 reduction in CRPC cells. Mechanistically, we observed that enhanced AKR1C3 expression in SULT2B-depleted cells was prevented upon genetic or pharmacologic inactivation of LXR. In addition, ERRα, another non-steroid nuclear receptor, was reduced in LXR-inactivated cells and notably, AKR1C3 was reduced in CRPC cells upon ERRα degradation by an ERRα-selective PROTAC. The LXR dependence of ERRα and AKR1C3 expression was observed in both androgen receptor expressing and non-expressing CRPC cells.

Conclusion & Translational Significance: Above results reveal a novel LXR-ERRα-AKR1C3-ERK axis which is activated in SULT2B-deficient CRPC cells irrespective of the androgen receptor status of these cells. Notably, elevated ERRα portends poor prognosis for prostate cancer and cholesterol is an ERRα agonist. Considering that statin can diminish ERRα activity (PMID 26777690) and AKR1C3 inhibitors are in clinical trials, this novel axis revealed from our study may be actionable for the clinical interception of the progression in SULT2B-low advanced prostate cancer.

Citation Format: Bobae Park, Katarzyna Knapczyk-Stwora, Yaguang Liu, Chung S. Song, Bandana Chatterjee. Leveraging oxysterol sulfation by SULT2B1b sulfotransferase and liver X receptor inactivation to suppress advanced prostate cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 3070.
Abstract 3099: Hnd-01: a potent inhibitor of wild type mutant BTK
Authors: Zhang Jing , Samatar Ahmed A. , Tan Yue , Pi Shiqing , Zhou Zhigang , Xu Yan , Yang Daihong
Published: April 2023

Dasatinib is an oral dual BCR/ABL and Src family tyrosine kinase inhibitor approved for use in patients with chronic myelogenous leukemia and Philadelphia chromosome-positive acute lymphoblastic leukemia. Based on the in vitro and in vivo characterization studies of dasatanib, several metabolites were identified. Dasatinib and its metabolite 20 were the major circulating species identified which represented 25.5% and 12.5% of total radioactivity in human plasma respectively. Here, we report the identification of HND-01, a small molecule inhibitor of Bruton’s tyrosine kinase (BTK) which was achieved by modifying metabolite 20 of dasatinib. Bruton’s tyrosine kinase (BTK) is a non-receptor kinase and a key regulator of the B-cell receptor (BCR) signaling pathway. BCR is critical for proliferation and survival of leukemic cells in many B cell malignancies, including chronic lymphocytic leukemia (CLL). BTK is a key target for the development of small molecule inhibitors in B cell malignancies. There are several covalent BTK inhibitors including ibrutinib that have been approved. These covalent inhibitors bind with high affinity to Cys-481 in the active site of BTK. However, some patients develop acquired resistance to ibrutinib due to Cys-481 mutation in the BTK binding site. The acquired resistance to covalent inhibitors can be overcome with the design of new reversible BTK inhibitors. The reversible BTK inhibitors will bind to different sites other than the cysteine residue of BTK and inactivate BTK. These drugs would potentially be active in the presence or absence of the cysteine-to-serine mutation. HND-01, a novel and potent reversible BTK inhibitor inhibits wild type & C481S mutant BTK with IC50 values of 0.157 nM for WTBTK and 0.032 nM for C481SBTK. HND-01 inhibits K562 cell proliferation (IC50 0.183 nM) and it is more stable than dasatinib in human liver microsomes (in vitro clearance; 142 mL/min/kg for HND-01 vs 211 mL/min/kg for dasatinib). In an established human lymphoma efficacy model (TMD-8 model), HND-01 showed stronger tumor inhibition (80.6%) than Ibrutinib (58%). These data demonstrates that HND-01 is a BTK inhibitor that is more potent with potential desirable ADME properties than ibrutinib. HND-01 was filled for international patents, China patent application # 202080030953.6, US patent application #17/636,476, EU application # EP 20853834.8, and Canada application # CA 3148436.

Citation Format: Jing Zhang, Ahmed A. Samatar, Yue Tan, Shiqing Pi, Zhigang Zhou, Yan Xu, Daihong Yang. Hnd-01: a potent inhibitor of wild type mutant BTK [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 3099.
Abstract 3106: Design, synthesis, and screening of niclosamide analogs as androgen receptor degraders for hepatocellular carcinoma
Authors: Cheng Jeffrey , Xing Enming , Mohammed Shabber , Montgomery Emma , Granchie Lauren , Coss Christopher , Li Pui-Kai
Published: April 2023

Hepatocellular Carcinoma (HCC) is the leading form of liver cancer, the 6th most common type, and the 4th leading cause of cancer death worldwide. Interestingly, HCC occurs two to four times more in males than females. A possible explanation for this sexual dimorphism is the implication of androgen and the Androgen Receptor (AR). However, previous clinical trials among HCC patients have shown no significant survival benefit after the administration of antiandrogen drugs (e.g. Enzalutamide) that block the Ligand-Binding Domain (LBD) of the Full-length Androgen Receptor (AR-FL). Instead, our lab has developed a novel approach using small molecular analogs of the previously FDA-approved drug, Niclosamide, to degrade full-length AR and its spliced variants within HCC cell lines. The primary goal of this project was to evaluate the minimal necessary pharmacophores for the biological activity of the Niclosamide scaffold. To do so, 23 analogs were synthesized and tested on three different HCC cell lines (SNU 475, 423, and LM3) using a CCK8 cell viability assay. Preliminary results have shown that only Niclosamide analogs with i.) electron-withdrawing groups on the aniline ring; ii) a conserved hydroxy group on the salicylic ring, and iii) a free amide group in the middle have cytotoxic activity. Further work will be completed using western blot to determine if there’s any correlation between androgen receptor degradation and in vitro potency. In conclusion, Niclosamide analogs have indicated promising potential to inhibit HCC cell lines by targeting the Androgen Receptor.

Citation Format: Jeffrey Cheng, Enming Xing, Shabber Mohammed, Emma Montgomery, Lauren Granchie, Christopher Coss, Pui-Kai Li. Design, synthesis, and screening of niclosamide analogs as androgen receptor degraders for hepatocellular carcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 3106.
Abstract 3120: Sex differences in pediatric cancer genomics
Authors: Oh Jieun , Zhu Chenghao , Zeltser Nicole , Li Constance H. , Tsai Brandon L. , Boutros Paul C.
Published: April 2023

Sex differences have been observed in the incidence, prognosis and mortality of many different adult cancer types, linked to differences in tumor genomics. By contrast, sex differences in pediatric cancers have been understudied, with almost no genomic studies. To fill this gap, we have performed analyses on the genome, epigenome and transcriptome in eight different pediatric cancer types in nearly 3,000 tumors. Pediatric cancers had distinctive somatic mutational patterns when it came to sex differences, with acute lymphoblastic leukemia exhibiting sex-biases in its transcriptome and other cancer types showing stronger biases in their methylomes. However, no sex differences in somatic mutational profiles were identified. This stands in stark contrast to adult tumors, where we further previous genomic and transcriptomic studies by identifying sex differences in the proteomes, in drug sensitivity profiles and in functional genomics. In summary, our study reveals that sex differences in pediatric cancers are more modest than those in adult tumors and this may shed light into potential mechanisms by which sex influences the cancer genome.

Citation Format: Jieun Oh, Chenghao Zhu, Nicole Zeltser, Constance H. Li, Brandon L. Tsai, Paul C. Boutros. Sex differences in pediatric cancer genomics [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 3120.
Abstract 3137: Somatic structure variants as a biomarker to predict immune checkpoint inhibitor response by generating anti-tumour antigen
Authors: Cha Hongui , Simpson Benjamin , Swanton Charles , Litchfield Kevin , Consortium Genomics England Research
Published: April 2023

The introduction of checkpoint inhibitors (CPI) has revolutionised the treatment of advanced cancers, which act to ameliorate the anti-tumour response through blocking inhibitive immune checkpoint receptors. Whole-exome sequencing (WES) based estimates of tumour mutational burden (TMB) has been robustly associated with response to CPI therapy across multiple tumour types and a threshold of ≥10 mutations per megabase (Mb) is now an FDA-approved biomarker for treatment with pembrolizumab. However, studies to date have been limited to whole exome sequencing (WES), with no data yet reported on the utility of whole genome sequencing (WGS) as a biomarker to predict CPI response. WGS data can identify non-coding alterations which impact the expression of immune regulatory genes, variants likely to form non-coding epitopes, including novel open reading frame mutations especially structure variants (SV). Here, we have identified a pan-cancer cohort of n=364 patients treated with CPI from Genomics England 100,000 Genomes Project (GEL). We find that SV burden is highly associated with worse CPI response (HR =1.3 (1.0-1.8) , p-value = 0.037) and high SV burden group have low tumour-infiltrating lymphocyte (TIL) score (P-value < 0.0001). However, we found that patients who have high proportion of SV derived neoantigen group improved overall survival (HR = 0.44 (0.27-0.73) , p-value = 0.002). In addition, enhancer region alteration of antigen present gene was observed in 43 patients (12%) and was associated with worse CPI response. (HR = 1.5 (1.0-2.2), P-value = 0.034). We further explored the SV derived neoantigen generate neoantigen-specific T cell response.

Summary of Cox Model from structure variant Variables No. patients HR (95% CI) P Sex Female 164 Male 200 1.15 ( 0.87-1.52) 0.3285 Cancer Type Others 59 Lung 88 1.39 (0.91-2.14) 0.1255 Melanoma 155 0.84 (0.56-1.28) 0.4267 Renal 62 0.84 (0.52-1.38) 0.495 TMB estimated WGS 364 0.98 (0.97-0.99) 0.0036 SV burden Low 182 High 182 1.36 (1.02-1.81) 0.0358 Proportion of anti-tumour antigen from SV Low 49 High 47 0.48 (0.29-0.8) 0.0045 antigen non-generate 268 0.49 (0.35-0.7) < 0.0001

Citation Format: Hongui Cha, Benjamin Simpson, Charles Swanton, Kevin Litchfield, Genomics England Research Consortium. Somatic structure variants as a biomarker to predict immune checkpoint inhibitor response by generating anti-tumour antigen [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 3137.
Abstract 3138: Topological analysis of spatial transcriptomics reveals different spatial interaction patterns in tumor microenvironment of lung cancer
Authors: Bae Sungwoo , Lee Hyekyoung , Na Kwon Joong , Lee Dong Soo , Choi Hongyoon , Kim Young Tae
Published: April 2023

Background: As the tumor microenvironment (TME) consists of various cell types with complex spatial interaction, its spatial organization patterns affect response to immune-oncology treatment. Therefore, describing the spatial composition and interaction of cells in the tumor microenvironment (TME) is necessary. Here, we developed a tool, STopover, which adopts topological analysis in spatial transcriptomics to reveal cell-cell colocalization patterns in TME and capture the key components and niche of intercellular communication, and applied it to human lung cancer data.

Methods: The spatial colocalization pattern of pairs of features was defined using topological data analysis with Morse filtration. The spatial network of spatial gene expression data was generated for each sample and then the patterns were summarized as connected components (CCs) based on the spatial distance between unit tissue regions and the persistence of each CC. The global and local extent of spatial overlap of a feature pair was calculated as Jaccard indices between extracted CC pairs. We applied STopover to 11 barcode-based spatial transcriptomic data of human lung adenocarcinoma with different PD-L1 expressions. Spatial mapping of cell types in TME was performed by CellDART. In addition, image-based spatial transcriptomic data of lung cancer were also used to find key spatial molecular interactions in TME using STopover.

Results: First, STopover disclosed the distinct immune and stromal infiltration patterns in lung cancer tissues. Spatial colocalization of cancer cells and T-cells was heterogeneous and correlated with the immune-related markers such as MHC class I signature. The cancer types were clustered according to spatial colocalization patterns of various immune cells with cancer cells, which showed different infiltration patterns of immune cells. Moreover, STopover could estimate the top cell-cell interaction and emphasize the key locations based on the literature-supported ligand-receptor database.

Conclusion: STopover is expected to account for significant spatial cell interactions in tumor-immune and tumor-stromal components and could be utilized as a platform to decipher the mechanisms underlying immune-oncology treatment response.

Citation Format: Sungwoo Bae, Hyekyoung Lee, Kwon Joong Na, Dong Soo Lee, Hongyoon Choi, Young Tae Kim. Topological analysis of spatial transcriptomics reveals different spatial interaction patterns in tumor microenvironment of lung cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 3138.
Abstract 3174: Integrative analysis of genome-wide DNA replication origins in human cells
Authors: Tian Mengxue , Wang Zhenjia , Zang Chongzhi , Su Zhangli , Shibata Etsuko , Shibata Yoshiyuki , Dutta Anindya
Published: April 2023

Dysregulated DNA replication is associated with cancer development. DNA replication initiates from ~50,000 sites in each cell cycle. Genome-wide profiles of replication origins can be generated using various sequencing-based methods following different molecular capture strategies. No previous study has integrated the results from these different experiments to characterize the most reproducible origins or their association with the replication initiation factor, Origin Recognition Complex (ORC), known to be important for origin-specification. We conducted an integrative analysis of 98 human origin profiling datasets from four different techniques including NS-seq, Repli-seq, Rerep-seq and Bubble-seq, and identified a total of 1,460,610 origins in the human genome. Of these, only 0.12% (1,746) were high-confidence “shared origins” that were detected by all four techniques. Compared with all origins, the shared origins have higher GC content and overlap more with gene promoters, CTCF binding sites, transcription factor (TF) binding hotspots, G-quadruplex sites and activating histone marks. Only ~20% of the shared origins (343) overlap with known ORC binding sites. Despite the low overlap between shared origins and ORC binding sites, permutation tests suggest that the overlap between shared origins, ORC binding sites, R-loops and promoters are all significantly higher than random expectation. The variability in origin identification by different techniques and by same techniques in different groups suggests that replication origins are specified by highly variable stochastic events influenced by epigenetic variability.

Citation Format: Mengxue Tian, Zhenjia Wang, Chongzhi Zang, Zhangli Su, Etsuko Shibata, Yoshiyuki Shibata, Anindya Dutta. Integrative analysis of genome-wide DNA replication origins in human cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 3174.
Abstract 3219: Development of a quality-of-life assessment module in patients with radiation dermatitis
Authors: Allen Olivia S. , Moadel-Robblee Alyson B. , Fox Jana , Yap Johnny , McLellan Beth N.
Published: April 2023

Introduction: Radiation dermatitis (RD) is one of the most common side effects of radiation therapy (RT), experienced by up to 95% of oncology patients. RD can be progressive, painful, and difficult to manage, thereby profoundly affecting patients’ quality of life (QOL). Current QOL assessments address dermatologic or oncologic concerns, with no existing tool integrating both areas to enable assessment of RD-specific QOL. Furthermore, RD grade does not consistently correlate with QOL scores in these assessments. The aims of this study are to identify unexplored QOL concerns in patients with RD and to create a new, RD-specific, validated assessment module to evaluate QOL in this patient population.

Methods: We conducted open-ended interviews with 20 patients with breast cancer with current or former RD during a radiation oncology clinic visit to determine RD-specific QOL concerns. We analyzed the most high-yield concerns to determine areas that are not addressed by current QOL assessments. With a workgroup of radiation oncologists, dermatologists, a psycho-oncologist, and patients, we evaluated our findings and used common themes to generate a new QOL survey.

Results: Among our patient cohort, 3 (15%) were undergoing current RT, 7 (35%) were at their first post-RT visit, 9 (45%) were at a follow-up visit within 12 months of completing RT, and 1 (5%) was at a follow-up visit over 12 months after completing RT. We uncovered four key areas affecting patients that are not incorporated into current QOL assessments: changes in clothing in 18 (90%) patients (e.g. wearing looser clothing, changing to a different bra, using a layer of bandages), changes in skin color in 17 (85%) patients (hyper- or hypopigmentation), changes in sleep due to skin changes in 13 (65%) patients (e.g. difficulty finding a comfortable position), and changes in ability to use the affected side in 9 (45%) patients (e.g. carrying items, avoiding contact with irritating material). We incorporated these four areas of concern into a six-question, RD-specific QOL assessment module to the Skindex-16, a validated and widely used QOL assessment in dermatology.

Conclusions: This pilot study enabled us to discover previously unexplored QOL concerns in patients with RD that are not addressed in current dermatology and oncology focused assessments. Future work includes validation of this module in patients with acute RD with the goal of identifying opportunities to optimize treatment and enhance patient-centered care for this population.

Citation Format: Olivia S. Allen, Alyson B. Moadel-Robblee, Jana Fox, Johnny Yap, Beth N. McLellan. Development of a quality-of-life assessment module in patients with radiation dermatitis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 3219.