bluuebunny/crossref_metadata_2025_split huggingface dataset:
Abstract 5905: Propentofylline enhances GBM sensitivity to temozolomide via targeting TROY signaling
Authors: Eghlimi Ryan , Nascari David , Beniwal Angad , Alton Drake , Grief Dustin , Loftus Joseph , Haluska Melanie , Coleman David , Tran Nhan 
Published: March 2024

Abstract
Glioblastoma (GBM) is a high grade glioma that accounts for the majority of primary malignant brain tumors. The standard of care for GBM consists of maximal surgical resection, concurrent radiation and temozolomide (TMZ), and adjuvant TMZ. However, this has only led to a modest increase in median patient survival. TROY (TNFRSF19) is an orphan member of the TNF receptor superfamily that is differentially upregulated in GBM with low expression in normal brain tissue. Previously, we have reported that TROY is overexpressed in GBM and signals to mediate cell invasion and therapeutic resistance. Propentofylline (PPF) is a well-studied synthetic methylxanthine derivative that has strong BBB penetrance. We have shown that PPF decreases TROY expression in gliomas, inhibits invasion, and sensitizes GBM to TMZ in vitro. Here we examined the efficacy of PPF in combination with TMZ using in vivo studies of intracranial models of GBM patient-derived xenograft (PDX) models in murine. We tested 3 models of GBM PDX cells with various TROY expression levels (GBM8-high TROY; GBM43-moderate TROY; GBM22-low/no TROY). Our intracranial PDX experiments showed that PPF treatment alone did not increase survival in all PDX cells. The combination of PPF and TMZ treatment did provide a survival benefit (p &lt; 0.039) relative to TMZ alone (only in GBM8-high TROY and GBM43-moderate TROY) that was partially lost when treatment was discontinued. However, continuous PPF administration following a concomitant PPF and TMZ treatment course led to extended survival (p &lt; 0.0015) compared to TMZ alone resulting in increased DNA damage (γH2AX) and apoptotic markers (Cleaved Caspase-3). Immunohistochemical analyses showed that TROY expression was decreased in tumors treated with PPF. In addition, PPF-treated tumors showed a differential myeloid population with well circumscribed tumors as compared to control-treated or TMZ-treated tumors. Thus, our data demonstrates that PPF may provide a pharmacological approach to targeting TROY concomitant with standard-of-care to increase patient survival.
Citation Format: Ryan Eghlimi, David Nascari, Angad Beniwal, Drake Alton, Dustin Grief, Joseph Loftus, Melanie Haluska, David Coleman, Nhan Tran. Propentofylline enhances GBM sensitivity to temozolomide via targeting TROY signaling [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5905.
Abstract 5931: Investigating the therapeutic potential of STK17A inhibition in GBM
Authors: Castro Jesus R. 
Published: March 2024

Abstract
For decades, the survival rate for glioblastoma (GBM) has remained nearly stagnant, and currently the 5-year survival rate is only 5%. There is an unmet medical need for therapeutic development, as GBM is the most common primary brain tumor, yet only four FDA approved drugs have been developed for GBM over the last century. GBM is notoriously heterogeneous, and this has posed a challenge for researchers seeking to find therapeutic targets. However, by taking advantage of RNA sequencing, a potential biomarker and target for GBM has been identified: the kinase STK17A (Serine/Threonine Kinase 17A), also known as DRAK1. We confirmed that STK17A is overexpressed in brain cancers by analyzing public databases and single-cell RNA sequencing data from GBM patients, and further associated it with poor patient outcome. Little is known about STK17A, but it has been found to be involved with cell proliferation, tumorigenesis, and tumor metastasis. The role of STK17A in GBM pathophysiology and its therapeutic potential as a drug target remains a critical knowledge gap.In order to better understand STK17A’s role in GBM pathophysiology, we first knocked down STK17A in GBM cell lines and determined that STK17A had functional roles in proliferation and morphology. Similar conclusions were drawn after knocking down STK17A in vivo in GBM xenograft mouse models. These findings supported STK17A as a viable therapeutic target. We then designed and optimized novel brain-penetrant STK17A inhibitors with IC50 values of &lt;20nM in enzyme assays and &lt;1μM in cell-based targeting engagement and proliferative assays. The designed and prepared novel STK17A inhibitors were further evaluated through kinase enzymatic assays and biological assays as well as in vitro proliferation and toxicity assays. We further characterized the inhibitors by showing Drug Metabolism and Pharmacokinetics (DMPK) properties in vivo in mouse models at 10 mg/kg via oral administration. We then used these potent, selective, and highly brain penetrant STK17A inhibitors to investigate the anti-tumor effects of STK17A inhibition in GBM in vivo and demonstrate the efficacy of our novel STK17A inhibitors.In conclusion, this work seeks to contribute to the field of targeted therapies for GBM by optimizing and examining the first iterations of novel brain penetrant STK17A inhibitors, initiating studies for the treatment of GBM in vitro and in vivo, and providing proof of efficacy for further studies in GBM patients. Ultimately, the results from our findings will lead to novel strategies for targeted drug development and more robust therapeutic options for GBM patients.
Citation Format: Jesus R. Castro. Investigating the therapeutic potential of STK17A inhibition in GBM [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5931.
Abstract 5991: Improved venetoclax therapy by a novel conjugate with artemisinin by NOXA-mediated reduction of Mcl-1 and cyclin D1 protein in myeloid leukemia cells
Authors: Zhang Jingyi , Zhang Zhenwei , Waxman Samuel , Zhao Linxiang , Jing Yongkui 
Published: March 2024

Abstract
Evasion of apoptosis is crucial for the growth, survival and chemoresistance of myeloid leukemia. The Bcl-2 selective inhibitor venetoclax is the only apoptosis inducer approved for clinical use. Venetoclax in combination with hypomethylating agents or low-dose cytarabine has now become the standard care for elderly AML patients. However, a sizeable fraction of patients are either refractory to venetoclax combination therapy or ultimately relapse. High or induced expression of Mcl-1 and Bcl-xL mediates venetoclax resistance. Previously we reported that artemisinin enhances venetoclax apoptosis induction by degrading Mcl-1 through NOXA induction. We designed a novel conjugate A1 of venetoclax with dihydroartemisinin. A1 shows dual functions of inhibiting Bcl-2 and inducing NOXA. A1 treatment releases Bim from both Bcl-2 and Mcl-1, further degrades Mcl-1 protein, and presents ten-fold stronger apoptotic induction ability in venetoclax insensitive cells. Acquired increase of Mcl-1 protein was observed in venetoclax resistant MOLM-13/VEN cells, which are sensitive to A1-induced apoptosis. In Bcl-xL expressing venetoclax refractory leukemia cells A1 obtains a new mechanism of inhibiting cell cycling by downregulating cyclin D1 through a new NOXA/cyclin D1 cascade, mediated through the endoperoxide moiety of artemisinin and intracellular iron, independent of Bcl-2 inhibition. We reveal a new compound A1 overcoming venetoclax resistance by NOXA-mediated degradation of Mcl-1 and cyclin D1 protein.
Citation Format: Jingyi Zhang, Zhenwei Zhang, Samuel Waxman, Linxiang Zhao, Yongkui Jing. Improved venetoclax therapy by a novel conjugate with artemisinin by NOXA-mediated reduction of Mcl-1 and cyclin D1 protein in myeloid leukemia cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5991.
Abstract 60: Functional mapping of glioblastoma recurrence reveals targetable dependencies in an axonal guidance pathway in highly invasive brain cancers
Authors: Singh Sheila Kumari , Chokshi Chirayu , Shaikh Vaseem , Brakel Benjamin , Anand Alisha , Venugopal Chitra , Kislinger Thomas , Henry Kevin , Rossotti Martin , Brown Kevin , Lazo John , Moffat Jason 
Published: March 2024

Abstract
Resistance to genotoxic therapies and tumor recurrence are hallmarks of glioblastoma (GBM), an aggressive brain tumor. Here, we explore the functional drivers of post-treatment recurrent GBM. By conducting genome-wide CRISPR-Cas9 screens in patient-derived GBM models, we uncover distinct genetic dependencies in recurrent tumor cells that were absent in their patient-matched primary predecessors, accompanied by increased mutational burden and differential transcript and protein expression. These analyses map a multilayered genetic response to drive tumor recurrence, identifying protein tyrosine phosphatase 4A2 (PTP4A2) as a novel modulator of self-renewal, proliferation and tumorigenicity at GBM recurrence. Genetic perturbation or small molecule inhibition of PTP4A2 represses axon guidance activity through a dephosphorylation axis with roundabout guidance receptor 1 (ROBO1), exploiting a functional dependency on ROBO signaling. Importantly, engineered anti-ROBO1 single-domain antibodies also mimic effects of PTP4A2 inhibition. Since a pan-PTP4A inhibitor was limited by poor penetrance across the blood brain barrier (BBB) in vivo, a second-generation chimeric antigen receptor (CAR)-T cell therapy was engineered against ROBO1 that elicits specific and potent anti-tumor responses in vivo. A single dose of anti-ROBO1 CAR-T cells doubles median survival in patient-derived xenograft (PDX) models of recurrent glioblastoma, and also eradicates tumors in around 50% of mice engrafted with PDX models of lung-to-brain metastases and pediatric relapsed medulloblastoma. We conclude that functional reprogramming drives tumorigenicity and dependence on a multi-targetable PTP4A-ROBO1 signaling axis at GBM recurrence, with potential in other malignant brain tumors.
Citation Format: Sheila Kumari Singh, Chirayu Chokshi, Vaseem Shaikh, Benjamin Brakel, Alisha Anand, Chitra Venugopal, Thomas Kislinger, Kevin Henry, Martin Rossotti, Kevin Brown, John Lazo, Jason Moffat. Functional mapping of glioblastoma recurrence reveals targetable dependencies in an axonal guidance pathway in highly invasive brain cancers [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 60.
Abstract 6027: 89Zr-matuzumab and 225Ac-matuzumab as a theranostic for epidermal growth factor receptor-positive KRAS wild-type colorectal and breast cancer xenografts
Authors: Tikum Florence Anjong , Fonge Humphrey , Njotu Fabrice , Babeker Hanan , Pougoue Jessica K. , Henning Nikita , Doroudi Alireza 
Published: March 2024

Abstract
Background: About 80% of colorectal cancer (CRC) and 50 % of Triple-Negative breast cancer (TNBC) patients overexpress epidermal growth factor receptor (EGFR). Mutations in the KRAS oncogene (present in 40% of mCRC) lead to constitutive over-activation of EGFR and drive de novo resistance to anti-EGFR drugs. Here, we propose to target KRAS-mutant/BRAF mutant EGFR positive mCRC and TNBC using 225Ac-labeled matuzumab, a humanized anti-EGFR monoclonal antibody.
Methods: p- -SCN-macropa was used to conjugate matuzumab for radiolabeling with 225Ac and SCN-deferoxamine was used to conjugate matuzumab for labelling with 89Zr. The radioimmunoconjugates were characterized by flow cytometry, HPLC and iTLC. in vitro cytotoxicity was evaluated in EGFR-positive mCRC, TNBC cell lines and 3D spheroids with different levels of EGFR density. Tumor growth was monitored using digital caliper. Mice were treated with either 10 MBq of 89Zr-matuzumab for imaging or three doses of 13 KBq/dose administered of 225Ac-matuzumab 10 days apart. In vivo study endpoint was tumor volume greater than or equal to 1500 mm3.
Results: Flow cytometry showed about 95% binding to the cells in all EGFR-positive colorectal cell lines (DLD-1, SW620, SNU-C2B, HT-29) and breast cancer cell lines (MDA-MB-468, MDA-MB-231). in vitro studies showed enhanced cytotoxicity of 225Ac-matuzumab compared with matuzumab. IC50 in the MDA-MB-468 cell line for 225Ac-matuzumab (1.86 ± nM) was 35 times more effective than matuzumab (65.25± 7 nM). Similar trends were observed in the other KRAS-mutant mCRC cell lines and breast cancer cell lines. In 3D spheroid models, the IC50 of 225Ac-matuzumab (3.0 ± 2 nM) in MDA-MB-468, was 20.79 times more effective than matuzumab (62.3 ± 1.38 nM). Similar trends were observed for all the other spheroid models as well. High uptake of 89Zr-matuzumab was observed in both mCRC and TNBC xenografts. 225Ac-matuzumab slowed tumor growth rate in MDA-MB-468 and MDA-MB-231 tumors models compared with control antibody or non-treated controls for 30 days. This study is still ongoing and will last for 2 more months.
Conclusion: 225Ac-matuzumab shows very promising outcomes in KRAS-mutant mCRC models and breast cancer models and warrants further investigation.
Citation Format: Florence Anjong Tikum, Humphrey Fonge, Fabrice Njotu, Hanan Babeker, Jessica K. Pougoue, Nikita Henning, Alireza Doroudi. 89Zr-matuzumab and 225Ac-matuzumab as a theranostic for epidermal growth factor receptor-positive KRAS wild-type colorectal and breast cancer xenografts [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 6027.
Abstract 6042: CBP-8008: A first-in-class targeted pan-Bet protein degradation therapy using bi-specific XDC (Bi-XDC) technology for TNBC and mCRPC
Authors: Wang Tao , Zhang Zhiguang , Wang Guitao , Pan Fan , Huang Robert 
Published: March 2024

Abstract
Bi-XDC is a breakthrough cellular targeting technology using multi-targeting ligands to effectively deliver the payload to and into specific cells. Several anticancer Bi-ligand drug conjugates including CBP-1008, CBP-1018, and CBP-1019 have been brought into various clinical stages in China and US. Targeted protein degradation molecules can degrade previously “undruggable” target proteins through their catalytic mechanism of action. The field target protein degradation has evolved since 2001, and more than 20 PROTACs are under clinical trials at different stages.
To increase the efficacy vs. tolerability window, we combine Bi-XDC technology and the catalytic approach of targeted protein degradation, to form C-PROTAC, by taking advantage of our privileged Bi-XDC technology and PROTAC’s degradation property. Further medicinal chemistry optimization, spacer optimization, and evaluation of many linker payloads led to the identification of our preclinical candidate CBP-8008, a highly potent pan-Bet protein degrader conjugated to bi-ligand via a cleavable linker.
A small panel of cell lines was screened to identify which tumors were sensitive to the pan-Bet protein degradation. All the tested breast cancer and prostate cell lines were the most sensitive to the payload. CBP-8008 had a high affinity to the Prostate Specific Membrane Antigen (PSMA) and the folate receptor alpha (FRα). Much more CBP-8008 were binding the 293T-FP which overexpress both FR-α and PSMA than the cell lines which only express one target (293T-F or 293T-P) or negative cell line (293T). CBP-8008 can quickly enter cells through endocytosis after treatment for 15 min, and degradation of BRD2, BRD3, and BRD4 was observed in MDA-MB-231 after 6 h, which was similar to its payload. The compound was very stable in mouse and human plasma in vitro, and limited free payload was detected which potentially avoids hematotoxicity in clinical. In the tumor-beaning mice DMPK study, fewer free payload was detected in 6 hours while much more free payload was detected in the tumor than in the blood and the time was extended to 72 hours after a single dose treatment. We evaluated CBP-8008 in TNBC and mCRPC xenograft model and robust efficacy was observed as lower as 3 MPK, significantly better than BMS-986158, a potent Bet inhibitor in clinical.
In conclusion: CBP-8008 is currently in preclinical development as a potential first-in-class pan-Bet protein degradation therapy using Bi-XDC technology for TNBC and mCRPC
Citation Format: Tao Wang, Zhiguang Zhang, Guitao Wang, Fan Pan, Robert Huang. CBP-8008: A first-in-class targeted pan-Bet protein degradation therapy using bi-specific XDC (Bi-XDC) technology for TNBC and mCRPC [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 6042.
Abstract 6045: Development and characterization of ATC-324: An AUTOTAC-based androgen receptor degrader for prostate cancer treatment
Authors: Pham Tri , Bae Tae Hyun , Sung Ki Woon , Najy Abdo , Zamiri Alaleh , Jang Hyejeong , Mun Su Ran , Kim Seongho , Shi Dongping , Kregel Steven , Heath Elizabeth , Cher Michael , Kwon Yong Tae , Kim Hyeong-Reh 
Published: March 2024

Abstract
Prostate cancer (PCa) progression is largely driven by the androgen receptor (AR), making it a prime target for therapy. However, therapy resistance often arises due to AR mutations and splice variants, such as AR-v7. AUTOTAC (AUTOphagy-TArgeting Chimera) is a novel protein degradation platform that utilizes the autophagy-lysosomal pathway to selectively degrade disease-causing proteins. In this study, we characterize ATC-324, an AUTOTAC-based AR degrader designed for the treatment of PCa. ATC-324 comprises enzalutamide linked to YT 6-2, a small molecule activator of the autophagy receptor p62/SQSTM1. ATC-324 induces the formation of the AR/p62 complex while activating autophagic flux, leading to the autophagy-lysosomal degradation of AR. To characterize ATC-324, we employed various AR-dependent, AR-null, and enzalutamide-resistant PCa cell lines. Given that bone metastasis is a major clinical complication of castrate-resistant PCa associated with greater morbidity and mortality, we utilized the bone-in-culture array (BICA) assay, an ex vivo bones culture model, to investigate the impact of ATC-324 on PCa cell survival and growth in the bone microenvironment. We demonstrated that ATC-324 effectively degrades wild-type, mutant, and splice variants of AR. In addition, ATC-324 induces AR-dependent apoptosis and cytotoxicity. Importantly, ATC-324 maintains its potency in enzalutamide-resistant PCa cells. Utilizing the BICA assay, we showed that ATC-324 exhibits cytotoxicity against 22Rv1 bone micrometastases at even lower concentrations than in 2D cell culture. In conclusion, our study demonstrates the successful development and characterization of ATC-324 as a potent and selective degrader of various forms of AR. Furthermore, its effectiveness against enzalutamide-resistant cells indicates its capability to overcome therapy resistance. The observed cytotoxicity against bone micrometastases suggests a therapeutic potential for combating bone metastasis, a major complication of castration-resistant PCa. Our study underscores the potential of the AUTOTAC platform to selectively degrade disease-causing proteins
Citation Format: Tri Pham, Tae Hyun Bae, Ki Woon Sung, Abdo Najy, Alaleh Zamiri, Hyejeong Jang, Su Ran Mun, Seongho Kim, Dongping Shi, Steven Kregel, Elizabeth Heath, Michael Cher, Yong Tae Kwon, Hyeong-Reh Kim. Development and characterization of ATC-324: An AUTOTAC-based androgen receptor degrader for prostate cancer treatment [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 6045.
Abstract 6057: Evaluation of a highly potent and selective STAT3 degrader as a new class of immunotherapy
Authors: Bai Longchuan , Zhou Haibin , Zhou Jiajia , Wu Dimin , Acharyya Ranjan Kumar , Metwally Hoda , McEachern Donna , Wen Bo , Sun Duxin , Zou Weiping , Wang Shaomeng 
Published: March 2024

Abstract
STAT3 (signal transducer and activator of transcription 3) is a transcription factor and a promising therapeutic target for cancer and other human diseases. In addition to its role in regulation of tumor cells, STAT3 also plays a key role in regulation of immunity and is a promising therapeutic target for the development of new immuno-oncology drugs. Our laboratory has previously reported the development of potent and highly selective STAT3 degraders, including SD-36 and SD-91. Extensive optimization of SD-36 and SD-91 yielded new, highly potent, selective and efficacious STAT3 degraders. In direct comparison, our most potent, new STAT3 degrader (compound 1) is &gt;50-times more potent than SD-36 in inducing STAT3 degradation in cells and demonstrates &gt;500-fold degradation selectivity over other STAT members. A single intravenous administration of compound 1 in mice is highly effective in inducing complete depletion of STAT3 protein in tissues for 48-96 h without reducing the levels of other STAT proteins. Compound 1 is very effective in inhibition of tumor growth not only in tumor models responsive to immune checkpoint blockade (ICB) but also in tumor models resistant to ICB. Furthermore, combination of compound 1 with PD-1/PD-L1 antibodies greatly enhances the antitumor activity as compared to SD-1218 or ICB. Of significance, compound 1 is well tolerated in mice without any signs of toxicity in mice at highly efficacious doses. Our mechanistic studies show that STAT3 depletion has a major effect in modulation of the immune cells in mice. Collectively, our data suggest that selective STAT3 degradation hold great promise for new cancer immunotherapy.
Citation Format: Longchuan Bai, Haibin Zhou, Jiajia Zhou, Dimin Wu, Ranjan Kumar Acharyya, Hoda Metwally, Donna McEachern, Bo Wen, Duxin Sun, Weiping Zou, Shaomeng Wang. Evaluation of a highly potent and selective STAT3 degrader as a new class of immunotherapy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 6057.