bluuebunny/crossref_metadata_2025 huggingface dataset:
Data from Noninvasive Detection of ctDNA Reveals Intratumor Heterogeneity and Is Associated with Tumor Burden in Gastrointestinal Stromal Tumor
Authors: Namløs Heidi M. , Boye Kjetil , Mishkin Skyler J. , Barøy Tale , Lorenz Susanne , Bjerkehagen Bodil , Stratford Eva W. , Munthe Else , Kudlow Brian A. , Myklebost Ola , Meza-Zepeda Leonardo A.
Published: March 2024

Abstract
Molecular analysis of circulating tumor DNA (ctDNA) has a large potential for clinical application by capturing tumor-specific aberrations through noninvasive sampling. In gastrointestinal stromal tumor (GIST), analysis of KIT and PDGFRA mutations is important for therapeutic decisions, but the invasiveness of traditional biopsies limits the possibilities for repeated sampling. Using targeted next-generation sequencing, we have analyzed circulating cell-free DNA from 50 GIST patients. Tumor-specific mutations were detected in 16 of 44 plasma samples (36%) from treatment-naïve patients and in three of six (50%) patients treated with tyrosine kinase inhibitors. A significant association between detection of ctDNA and the modified National Institutes of Health risk classification was found. All patients with metastatic disease had detectable ctDNA, and tumor burden was the most important detection determinant. Median tumor size was 13.4 cm for patients with detectable mutation in plasma compared with 4.4 cm in patients without detectable mutation (P = 0.006). ctDNA analysis of a patient with disease progression on imatinib revealed that multiple resistance mutations were synchronously present, and detailed analysis of tumor tissue showed that these were spatially distributed in the primary tumor. Plasma samples taken throughout the course of treatment demonstrated that clonal evolution can be monitored over time. In conclusion, we have shown that detection of GIST-specific mutations in plasma is particularly feasible for patients with high tumor burden. In such cases, we have demonstrated that mutational analysis by use of liquid biopsies can capture the molecular heterogeneity of the whole tumor, and may guide treatment decisions during progression. Mol Cancer Ther; 17(11); 2473–80. ©2018 AACR.
Data from TAS6417, A Novel EGFR Inhibitor Targeting Exon 20 Insertion Mutations
Authors: Hasako Shinichi , Terasaka Miki , Abe Naomi , Uno Takao , Ohsawa Hirokazu , Hashimoto Akihiro , Fujita Ryoto , Tanaka Kenji , Okayama Takashige , Wadhwa Renu , Miyadera Kazutaka , Aoyagi Yoshimi , Yonekura Kazuhiko , Matsuo Kenichi
Published: March 2024

Abstract
Activating mutations in the EGFR gene are important targets in cancer therapy because they are key drivers of non–small cell lung cancer (NSCLC). Although almost all common EGFR mutations, such as exon 19 deletions and the L858R point mutation in exon 21, are sensitive to EGFR-tyrosine kinase inhibitor (TKI) therapies, NSCLC driven by EGFR exon 20 insertion mutations is associated with poor clinical outcomes due to dose-limiting toxicity, demonstrating the need for a novel therapy. TAS6417 is a novel EGFR inhibitor that targets EGFR exon 20 insertion mutations while sparing wild-type (WT) EGFR. In cell viability assays using Ba/F3 cells engineered to express human EGFR, TAS6417 inhibited EGFR with various exon 20 insertion mutations more potently than it inhibited the WT. Western blot analysis revealed that TAS6417 inhibited EGFR phosphorylation and downstream molecules in NSCLC cell lines expressing EGFR exon 20 insertions, resulting in caspase activation. These characteristics led to marked tumor regression in vivo in both a genetically engineered model and in a patient-derived xenograft model. Furthermore, TAS6417 provided a survival benefit with good tolerability in a lung orthotopic implantation mouse model. These findings support the clinical evaluation of TAS6417 as an efficacious drug candidate for patients with NSCLC harboring EGFR exon 20 insertion mutations. Mol Cancer Ther; 17(8); 1648–58. ©2018 AACR.
Data from HMG-CoA Reductase Inhibition Delays DNA Repair and Promotes Senescence After Tumor Irradiation
Authors: Efimova Elena V. , Ricco Natalia , Labay Edwardine , Mauceri Helena J. , Flor Amy C. , Ramamurthy Aishwarya , Sutton Harold G. , Weichselbaum Ralph R. , Kron Stephen J.
Published: March 2024

Abstract
Despite significant advances in combinations of radiotherapy and chemotherapy, altered fractionation schedules and image-guided radiotherapy, many cancer patients fail to benefit from radiation. A prevailing hypothesis is that targeting repair of DNA double strand breaks (DSB) can enhance radiation effects in the tumor and overcome therapeutic resistance without incurring off-target toxicities. Unrepaired DSBs can block cancer cell proliferation, promote cancer cell death, and induce cellular senescence. Given the slow progress to date translating novel DSB repair inhibitors as radiosensitizers, we have explored drug repurposing, a proven route to improving speed, costs, and success rates of drug development. In a prior screen where we tracked resolution of ionizing radiation-induced foci (IRIF) as a proxy for DSB repair, we had identified pitavastatin (Livalo), an HMG-CoA reductase inhibitor commonly used for lipid lowering, as a candidate radiosensitizer. Here, we report that pitavastatin and other lipophilic statins are potent inhibitors of DSB repair in breast and melanoma models both in vitro and in vivo. When combined with ionizing radiation, pitavastatin increased persistent DSBs, induced senescence, and enhanced acute effects of radiation on radioresistant melanoma tumors. shRNA knockdown implicated HMG-CoA reductase, farnesyl diphosphate synthase, and protein farnesyl transferase in IRIF resolution, DSB repair, and senescence. These data confirm on-target activity of statins, although via inhibition of protein prenylation rather than cholesterol biosynthesis. In light of prior studies demonstrating enhanced efficacy of radiotherapy in patients taking statins, this work argues for clinical evaluation of lipophilic statins as nontoxic radiosensitizers to enhance the benefits of image-guided radiotherapy. Mol Cancer Ther; 17(2); 407–18. ©2017 AACR.

See all articles in this MCT Focus section, “Developmental Therapeutics in Radiation Oncology.”
Data from JAK2 Inhibitor SAR302503 Abrogates PD-L1 Expression and Targets Therapy-Resistant Non–small Cell Lung Cancers
Authors: Pitroda Sean P. , Stack Melinda E. , Liu Gene-Fu , Song Sui-Sui , Chen Lucy , Liang Hua , Parekh Akash D. , Huang Xiaona , Roach Paul , Posner Mitchell C. , Weichselbaum Ralph R. , Khodarev Nikolai N.
Published: March 2024

Abstract
Lung cancer is the leading cause of cancer-related deaths worldwide. Approximately 85% of all lung cancers are non–small cell histology [non–small cell lung cancer (NSCLC)]. Modern treatment strategies for NSCLC target driver oncogenes and immune checkpoints. However, less than 15% of patients survive beyond 5 years. Here, we investigated the effects of SAR302503 (SAR), a selective JAK2 inhibitor, on NSCLC cell lines and tumors. We show that SAR is cytotoxic to NSCLC cells, which exhibit resistance to genotoxic therapies, such as ionizing radiation, cisplatin, and etoposide. We demonstrate that constitutive IFN-stimulated gene expression, including an IFN-related DNA damage resistance signature, predicts for sensitivity to SAR. Importantly, tumor cell–intrinsic expression of PD-L1 is IFN-inducible and abrogated by SAR. Taken together, these findings suggest potential dual roles for JAK2 inhibitors, both as a novel monotherapy in NSCLCs resistant to genotoxic therapies, and in tandem with immune checkpoint inhibition. Mol Cancer Ther; 17(4); 732–9. ©2018 AACR.
Data from Histone Deacetylase Inhibition Enhances the Antitumor Activity of a MEK Inhibitor in Lung Cancer Cells Harboring RAS Mutations
Authors: Yamada Tadaaki , Amann Joseph M. , Tanimoto Azusa , Taniguchi Hirokazu , Shukuya Takehito , Timmers Cynthia , Yano Seiji , Shilo Konstantin , Carbone David P.
Published: March 2024

Abstract
Non–small cell lung cancer (NSCLC) can be identified by precise molecular subsets based on genomic alterations that drive tumorigenesis and include mutations in EGFR, KRAS, and various ALK fusions. However, despite effective treatments for EGFR and ALK, promising therapeutics have not been developed for patients with KRAS mutations. It has been reported that one way the RAS–ERK pathway contributes to tumorigenesis is by affecting stability and localization of FOXO3a protein, an important regulator of cell death and the cell cycle. This is through regulation of apoptotic proteins BIM and FASL and cell-cycle regulators p21Cip1 and p27Kip1. We now show that an HDAC inhibitor affects the expression and localization of FOXO proteins and wanted to determine whether the combination of a MEK inhibitor with an HDAC inhibitor would increase the sensitivity of NSCLC with KRAS mutation. Combined treatment with a MEK inhibitor and an HDAC inhibitor showed synergistic effects on cell metabolic activity of RAS-mutated lung cancer cells through activation of FOXOs, with a subsequent increase in BIM and cell-cycle inhibitors. Moreover, in a mouse xenograft model, the combination of belinostat and trametinib significantly decreases tumor formation through FOXOs by increasing BIM and the cell-cycle inhibitors p21Cip1 and p27Kip1. These results demonstrate that control of FOXOs localization and expression is critical in RAS-driven lung cancer cells, suggesting that the dual molecular-targeted therapy for MEK and HDACs may be promising as novel therapeutic strategy in NSCLC with specific populations of RAS mutations. Mol Cancer Ther; 17(1); 17–25. ©2017 AACR.
Data from KRAS and EGFR Amplifications Mediate Resistance to Rociletinib and Osimertinib in Acquired Afatinib-Resistant NSCLC Harboring Exon 19 Deletion/T790M in EGFR
Authors: Nakatani Kaori , Yamaoka Toshimitsu , Ohba Motoi , Fujita Ken-Ichi , Arata Satoru , Kusumoto Sojiro , Taki-Takemoto Iori , Kamei Daisuke , Iwai Shinichi , Tsurutani Junji , Ohmori Tohru
Published: March 2024

Abstract
The critical T790M mutation in EGFR, which mediates resistance to first- and second-generation EGFR tyrosine kinase inhibitors (TKI; gefitinib, erlotinib, and afatinib), has facilitated the development of third-generation mutation-selective EGFR TKIs (rociletinib and osimertinib). We previously reported heterogeneous afatinib-resistant mechanisms, including emergence of T790M-EGFR, and responses to third-generation EGFR TKIs. Here, we used afatinib-resistant lung adenocarcinoma cells [AfaR (formerly AFR3) cells], carrying exon 19 deletion/T790M in EGFR. To identify the novel resistance mechanisms in post-afatinib treatment, RocR1/RocR2 and OsiR1/OsiR2 cells were established using increasing concentrations of rociletinib and osimertinib, respectively. Attenuation of exon 19 deletion and T790M was confirmed in both rociletinib-resistant cells; in addition, EGFR and KRAS amplification was observed in RocR1 and RocR2, respectively. Significant KRAS amplification was observed in the osimertinib-resistant cell lines, indicating a linear and reversible increase with increased osimertinib concentrations in OsiR1 and OsiR2 cells. OsiR1 cells maintained osimertinib resistance with KRAS amplification after osimertinib withdrawal for 2 months. OsiR2 cells exhibited KRAS attenuation, and osimertinib sensitivity was entirely recovered. Phospho-EGFR (Y1068) and growth factor receptor–bound protein 2 (GRB2)/son of sevenless homolog 1 (SOS1) complex was found to mediate osimertinib resistance in OsiR1 cells with sustained KRAS activation. After 2 months of osimertinib withdrawal, this complex was dissociated, and the EGFR signal, but not the GRB2/SOS1 signal, was activated. Concomitant inhibition of MAPK kinase and EGFR could overcome osimertinib resistance. Thus, we identified a heterogeneous acquired resistance mechanism for third-generation EGFR TKIs, providing insights into the development of novel treatment strategies.
Data from Targeting the BRD4-HOXB13 Coregulated Transcriptional Networks with Bromodomain-Kinase Inhibitors to Suppress Metastatic Castration-Resistant Prostate Cancer
Authors: Nerlakanti Niveditha , Yao Jiqiang , Nguyen Duy T. , Patel Ami K. , Eroshkin Alexey M. , Lawrence Harshani R. , Ayaz Muhammad , Kuenzi Brent M. , Agarwal Neha , Chen Yunyun , Gunawan Steven , Karim Rezaul M. , Berndt Norbert , Puskas John , Magliocco Anthony M. , Coppola Domenico , Dhillon Jasreman , Zhang Jingsong , Shymalagovindarajan Subramaniam , Rix Uwe , Kim Youngchul , Perera Ranjan , Lawrence Nicholas J. , Schonbrunn Ernst , Mahajan Kiran
Published: March 2024

Abstract
Resistance to androgen receptor (AR) antagonists is a significant problem in the treatment of castration-resistant prostate cancers (CRPC). Identification of the mechanisms by which CRPCs evade androgen deprivation therapies (ADT) is critical to develop novel therapeutics. We uncovered that CRPCs rely on BRD4-HOXB13 epigenetic reprogramming for androgen-independent cell proliferation. Mechanistically, BRD4, a member of the BET bromodomain family, epigenetically promotes HOXB13 expression. Consistently, genetic disruption of HOXB13 or pharmacological suppression of its mRNA and protein expression by the novel dual-activity BET bromodomain-kinase inhibitors directly correlates with rapid induction of apoptosis, potent inhibition of tumor cell proliferation and cell migration, and suppression of CRPC growth. Integrative analysis revealed that the BRD4-HOXB13 transcriptome comprises a proliferative gene network implicated in cell-cycle progression, nucleotide metabolism, and chromatin assembly. Notably, although the core HOXB13 target genes responsive to BET inhibitors (HOTBIN10) are overexpressed in metastatic cases, in ADT-treated CRPC cell lines and patient-derived circulating tumor cells (CTC) they are insensitive to AR depletion or blockade. Among the HOTBIN10 genes, AURKB and MELK expression correlates with HOXB13 expression in CTCs of mCRPC patients who did not respond to abiraterone (ABR), suggesting that AURKB inhibitors could be used additionally against high-risk HOXB13-positive metastatic prostate cancers. Combined, our study demonstrates that BRD4-HOXB13-HOTBIN10 regulatory circuit maintains the malignant state of CRPCs and identifies a core proproliferative network driving ADT resistance that is targetable with potent dual-activity bromodomain-kinase inhibitors.
Data from Targeting Polo-like Kinase 1 by a Novel Pyrrole-Imidazole Polyamide–Hoechst Conjugate Suppresses Tumor Growth In Vivo
Authors: Liu Ke , Fang Lijing , Sun Haiyan , Pan Zhengyin , Zhang Jianchao , Chen Juntao , Shao Ximing , Wang Wei , Tan Yuanyan , Ding Zhihao , Ao Lijiao , Wu Chunlei , Liu Xiaoqi , Li Huashun , Wang Rui , Su Wu , Li Hongchang
Published: March 2024

Abstract
The serine/threonine kinase Polo-like kinase 1 (Plk1) plays a pivotal role in cell proliferation and has been validated as a promising anticancer drug target. However, very limited success has been achieved in clinical applications using existing Plk1 inhibitors, due to lack of sufficient specificity toward Plk1. To develop a novel Plk1 inhibitor with high selectivity and efficacy, we designed and synthesized a pyrrole-imidazole polyamide–Hoechst conjugate, PIP3, targeted to specific DNA sequence in the PLK1 promoter. PIP3 could specifically inhibit the cell cycle–regulated Plk1 expression and consequently retard tumor cell growth. Cancer cells treated with PIP3 exhibited severe mitotic defects and increased apoptosis, whereas normal cells were not affected by PIP3 treatment. Furthermore, subcutaneous injection of PIP3 into mice bearing human cancer xenografts induced significant tumor growth suppression with low host toxicity. Therefore, PIP3 exhibits the potential as an effective agent for targeted cancer therapy. Mol Cancer Ther; 17(5); 988–1002. ©2018 AACR.
Data from Monitoring Tumor Burden in Response to FOLFIRINOX Chemotherapy Via Profiling Circulating Cell-Free DNA in Pancreatic Cancer
Authors: Wei Tao , Zhang Qi , Li Xiang , Su Wei , Li Guogang , Ma Tao , Gao Shunliang , Lou Jianying , Que Risheng , Zheng Lei , Bai Xueli , Liang Tingbo
Published: March 2024

Abstract
We aimed to explore the application of circulating cell-free DNA (cfDNA) profiling in monitoring tumor burden in patients with pancreatic ductal adenocarcinoma (PDAC). Thirty-eight patients with advanced PDAC receiving first-line FOLFIRINOX chemotherapy were prospectively enrolled. Next-generation sequencing for a panel of 560 genes covering a wide range of cancer-related loci was performed to profile cfDNA. In total, 25 patients (65.8%) had at least one common driver gene alterations (KRAS, TP53, SMAD4, CDKN2A) detected within cfDNA. In contrast, no above tumor-related recurrent mutations were found in plasma from 13 healthy individuals. Concordant alterations in plasma cfDNA and tumor tissue DNA was confirmed in two of three patients with available tissues. Further analysis showed that mutant allele fraction (MAF) for altered loci in cfDNA correlated with tumor stage, metastatic burden, and overall survival. Serial blood samples were collected from 17 patients after chemotherapy. We found that allele fraction for specific altered loci declined in chemotherapy-responding subjects. For cases who were resistant to this therapeutic regimen, increased ctDNA MAF was observed at the time of disease progression. Meanwhile, the dynamics of total cfDNA concentration correlated with tumor burden following chemotherapy. Collectively, we provide evidence that pretreatment ctDNA level correlates with tumor burden in PDAC, and serial cfDNA analysis is a robust tool for monitoring cancer response to chemotherapy.
Data from Arginine Deprivation Therapy: Putative Strategy to Eradicate Glioblastoma Cells by Radiosensitization
Authors: Hinrichs C. Noreen , Ingargiola Mirjam , Käubler Theresa , Löck Steffen , Temme Achim , Köhn-Luque Alvaro , Deutsch Andreas , Vovk Olena , Stasyk Oleh , Kunz-Schughart Leoni A.
Published: March 2024

Abstract
Tumor cells—even if nonauxotrophic—are often highly sensitive to arginine deficiency. We hypothesized that arginine deprivation therapy (ADT) if combined with irradiation could be a new treatment strategy for glioblastoma (GBM) patients because systemic ADT is independent of local penetration and diffusion limitations. A proof-of-principle in vitro study was performed with ADT being mimicked by application of recombinant human arginase or arginine-free diets. ADT inhibited two-dimensional (2-D) growth and cell-cycle progression, and reduced growth recovery after completion of treatment in four different GBM cell line models. Cells were less susceptible to ADT alone in the presence of citrulline and in a three-dimensional (3-D) environment. Migration and 3-D invasion were not unfavorably affected. However, ADT caused a significant radiosensitization that was more pronounced in a GBM cell model with p53 loss of function as compared with its p53-wildtype counterpart. The synergistic effect was independent of basic and induced argininosuccinate synthase or argininosuccinate lyase protein expression and not abrogated by the presence of citrulline. The radiosensitizing potential was maintained or even more distinguishable in a 3-D environment as verified in p53-knockdown and p53-wildtype U87-MG cells via a 60-day spheroid control probability assay. Although the underlying mechanism is still ambiguous, the observation of ADT-induced radiosensitization is of great clinical interest, in particular for patients with GBM showing high radioresistance and/or p53 loss of function. Mol Cancer Ther; 17(2); 393–406. ©2017 AACR.

See all articles in this MCT Focus section, “Developmental Therapeutics in Radiation Oncology.”
Data from Identification of FDA-Approved Oncology Drugs with Selective Potency in High-Risk Childhood Ependymoma
Authors: Donson Andrew M. , Amani Vladimir , Warner Elliot A. , Griesinger Andrea M. , Witt Davis A. , Levy Jean M. Mulcahy , Hoffman Lindsey M. , Hankinson Todd C. , Handler Michael H. , Vibhakar Rajeev , Dorris Kathleen , Foreman Nicholas K.
Published: March 2024

Abstract
Children with ependymoma (EPN) are cured in less than 50% of cases, with little improvement in outcome over the last several decades. Chemotherapy has not affected survival in EPN, due in part to a lack of preclinical models that has precluded comprehensive drug testing. We recently developed two human EPN cell lines harboring high-risk phenotypes which provided us with an opportunity to execute translational studies. EPN and other pediatric brain tumor cell lines were subject to a large-scale comparative drug screen of FDA-approved oncology drugs for rapid clinical application. The results of this in vitro study were combined with in silico prediction of drug sensitivity to identify EPN-selective compounds, which were validated by dose curve and time course modeling. Mechanisms of EPN-selective antitumor effect were further investigated using transcriptome and proteome analyses. We identified three classes of oncology drugs that showed EPN-selective antitumor effect, namely, (i) fluorinated pyrimidines (5-fluorouracil, carmofur, and floxuridine), (ii) retinoids (bexarotene, tretinoin and isotretinoin), and (iii) a subset of small-molecule multireceptor tyrosine kinase inhibitors (axitinib, imatinib, and pazopanib). Axitinib's antitumor mechanism in EPN cell lines involved inhibition of PDGFRα and PDGFRβ and was associated with reduced mitosis-related gene expression and cellular senescence. The clinically available, EPN-selective oncology drugs identified by our study have the potential to critically inform design of upcoming clinical studies in EPN, in particular for those children with recurrent EPN who are in the greatest need of novel therapeutic approaches. Mol Cancer Ther; 17(9); 1984–94. ©2018 AACR.
Data from TRP53 Mutants Drive Neuroendocrine Lung Cancer Through Loss-of-Function Mechanisms with Gain-of-Function Effects on Chemotherapy Response
Authors: Akeno Nagako , Reece Alisa L. , Callahan Melissa , Miller Ashley L. , Kim Rebecca G. , He Diana , Lane Adam , Moulton Jonathan S. , Wikenheiser-Brokamp Kathryn A.
Published: March 2024

Abstract
Lung cancer is the leading cause of cancer-related deaths with small-cell lung cancer (SCLC) as the most aggressive subtype. Preferential occurrence of TP53 missense mutations rather than loss implicates a selective advantage for TP53-mutant expression in SCLC pathogenesis. We show that lung epithelial expression of R270H and R172H (R273H and R175H in humans), common TRP53 mutants in lung cancer, combined with RB1 loss selectively results in two subtypes of neuroendocrine carcinoma, SCLC and large cell neuroendocrine carcinoma (LCNEC). Tumor initiation and progression occur in a remarkably consistent time frame with short latency and uniform progression to lethal metastatic disease by 7 months. R270H or R172H expression and TRP53 loss result in similar phenotypes demonstrating that TRP53 mutants promote lung carcinogenesis through loss-of-function and not gain-of-function mechanisms. Tumor responses to targeted and cytotoxic therapeutics were discordant in mice and corresponding tumor cell cultures demonstrating need to assess therapeutic response at the organismal level. Rapamycin did not have therapeutic efficacy in the mouse model despite inhibiting mTOR signaling and markedly suppressing tumor cell growth in culture. In contrast, cisplatin/etoposide treatment using a patient regimen prolonged survival with development of chemoresistance recapitulating human responses. R270H, but not R172H, expression conferred gain-of-function activity in attenuating chemotherapeutic efficacy. These data demonstrate a causative role for TRP53 mutants in development of chemoresistant lung cancer, and provide tractable preclinical models to test novel therapeutics for refractory disease. Mol Cancer Ther; 16(12); 2913–26. ©2017 AACR.
Data from Efficacy of the MDM2 Inhibitor SAR405838 in Glioblastoma Is Limited by Poor Distribution Across the Blood–Brain Barrier
Authors: Kim Minjee , Ma Daniel J. , Calligaris David , Zhang Shuangling , Feathers Ryan W. , Vaubel Rachael A. , Meaux Isabelle , Mladek Ann C. , Parrish Karen E. , Jin Fang , Barriere Cedric , Debussche Laurent , Watters James , Tian Shulan , Decker Paul A , Eckel-Passow Jeanette E. , Kitange Gaspar J. , Johnson Aaron J. , Parney Ian F. , Anastasiadis Panos Z. , Agar Nathalie Y.R. , Elmquist William F. , Sarkaria Jann N.
Published: March 2024

Abstract
Controversy exists surrounding whether heterogeneous disruption of the blood–brain barrier (BBB), as seen in glioblastoma (GBM), leads to adequate drug delivery sufficient for efficacy in GBM. This question is especially important when using potent, targeted agents that have a poor penetration across an intact BBB. Efficacy of the murine double minute-2 (MDM2) inhibitor SAR405838 was tested in patient-derived xenograft (PDX) models of GBM. In vitro efficacy of SAR405838 was evaluated in PDX models with varying MDM2 expression and those with high (GBM108) and low (GBM102) expression were evaluated for flank and orthotopic efficacy. BBB permeability, evaluated using TexasRed-3 kDa dextran, was significantly increased in GBM108 through VEGFA overexpression. Drug delivery, MRI, and orthotopic survival were compared between BBB-intact (GBM108-vector) and BBB-disrupted (GBM108-VEGFA) models. MDM2-amplified PDX lines with high MDM2 expression were sensitive to SAR405838 in comparison with MDM2 control lines in both in vitro and heterotopic models. In contrast with profound efficacy observed in flank xenografts, SAR405838 was ineffective in orthotopic tumors. Although both GBM108-vector and GBM108-VEGFA readily imaged on MRI following gadolinium contrast administration, GBM108-VEGFA tumors had a significantly enhanced drug and gadolinium accumulation, as determined by MALDI-MSI. Enhanced drug delivery in GBM108-VEGFA translated into a marked improvement in orthotopic efficacy. This study clearly shows that limited drug distribution across a partially intact BBB may limit the efficacy of targeted agents in GBM. Brain penetration of targeted agents is a critical consideration in any precision medicine strategy for GBM. Mol Cancer Ther; 17(9); 1893–901. ©2018 AACR.
Data from Cholesterol Depletion by TASIN-1 Induces Apoptotic Cell Death through the ER Stress/ROS/JNK Signaling in Colon Cancer Cells
Authors: Zhang Lu , Kim Sang Bum , Luitel Krishna , Shay Jerry W.
Published: March 2024

Abstract
Truncated APC selective inhibitor-1 (TASIN-1) is a recently identified small molecule that selectively kills colorectal cancer cells that express truncated adenomatous polyposis coli (APC) by reducing cellular cholesterol levels. However, the downstream mechanism responsible for its cytotoxicity is not well understood. In this study, we show that TASIN-1 leads to apoptotic cell death via inducing ER stress-dependent JNK activation in human truncated APC colon cancer cells, accompanied by production of reactive oxygen species (ROS). In addition, TASIN-1 inhibits AKT activity through a cholesterol-dependent manner. Human colon tumor xenografts in immunodeficient mice also show the same TASIN-1 induced molecular mechanisms of tumor cell death as observed in vitro. Taken together, cholesterol depletion by TASIN-1 treatment induces apoptotic cell death through activating ER stress/ROS/JNK axis and inhibiting AKT pro-survival signaling in colon cancer cells with truncated APC both in vitro and in vivo. Mol Cancer Ther; 17(5); 943–51. ©2018 AACR.
Data from Role of EphB3 Receptor in Mediating Head and Neck Tumor Growth, Cell Migration, and Response to PI3K Inhibitor
Authors: Bhatia Shilpa , Griego Anastacia , Lennon Shelby , Oweida Ayman , Sharma Jaspreet , Rohmer Christina , Uyanga Nomin , Bukkapatnam Sanjana , Van Court Benjamin , Raben David , Young Christian , Heasley Lynn , Karam Sana D.
Published: March 2024

Abstract
Eph proteins have emerged as critical drivers affecting tumor growth and progression in human malignancies. Our The Cancer Genome Atlas (TCGA) data analysis showed that EphB3, a receptor tyrosine kinase, is frequently coamplified with PIK3CA in head and neck squamous cell carcinoma (HNSCC). We therefore hypothesized that EphB3 amplification plays a protumorigenic role in HNSCC and that EphB3 and PIK3CA are cooperating oncogenes that contribute toward its pathogenesis. This hypothesis was not experimentally supported, because EphB3 knockdown failed to alter HNSCC tumor cell growth in vitro or in vivo with an orthotopic model. However, responsiveness of EphB3 knockdown tumors to the PI3K inhibitor, BKM120, was significantly decreased in terms of both tumor growth delay and survival. This is correlated with an increase in prosurvival proteins, S6 and BcL-XL, in the EphB3 shRNA tumors treated with BKM120 compared with controls. We further observed that EphB3 knockdown resulted in increased migration in vitro and increased EMT gene signature in vivo. To explain these results, we examined EphB3 phosphorylation levels in HNSCC at baseline. Although total EphB3 levels were high, we found low phospho-EphB3 levels in HNSCCs. Forced EphB3 phosphorylation with an ephrin-B2–Fc fusion protein resulted in decreased HNSCC migration and cell growth, and enhanced response to BKM120 in vitro. These data collectively indicate that progression of HNSCC selects for low/inhibited EphB3 activity to enhance their survival and migratory abilities and decrease response to PI3K signaling. Therefore, strategies focused on activating EphB3 might be helpful to inhibit tumor growth and enhance sensitivity to PI3K inhibitors in HNSCC. Mol Cancer Ther; 17(9); 2049–59. ©2018 AACR.
Data from TAS-114, a First-in-Class Dual dUTPase/DPD Inhibitor, Demonstrates Potential to Improve Therapeutic Efficacy of Fluoropyrimidine-Based Chemotherapy
Authors: Yano Wakako , Yokogawa Tatsushi , Wakasa Takeshi , Yamamura Keisuke , Fujioka Akio , Yoshisue Kunihiro , Matsushima Eiji , Miyahara Seiji , Miyakoshi Hitoshi , Taguchi Junko , Chong Khoon Tee , Takao Yayoi , Fukuoka Masayoshi , Matsuo Kenichi
Published: March 2024

Abstract
5-Fluorouracil (5-FU) is an antimetabolite and exerts antitumor activity via intracellularly and physiologically complicated metabolic pathways. In this study, we designed a novel small molecule inhibitor, TAS-114, which targets the intercellular metabolism of 5-FU to enhance antitumor activity and modulates catabolic pathway to improve the systemic availability of 5-FU. TAS-114 strongly and competitively inhibited deoxyuridine 5′-triphosphate nucleotidohydrolase (dUTPase), a gatekeeper protein preventing aberrant base incorporation into DNA, and enhanced the cytotoxicity of fluoropyrimidines in cancer cells; however, it had little intrinsic activity. In addition, TAS-114 had moderate and reversible inhibitory activity on dihydropyrimidine dehydrogenase (DPD), a catabolizing enzyme of 5-FU. Thus, TAS-114 increased the bioavailability of 5-FU when coadministered with capecitabine in mice, and it significantly improved the therapeutic efficacy of capecitabine by reducing the required dose of the prodrug by dual enzyme inhibition. Enhancement of antitumor efficacy caused by the addition of TAS-114 was retained in the presence of a potent DPD inhibitor containing oral fluoropyrimidine (S-1), indicating that dUTPase inhibition plays a major role in enhancing the antitumor efficacy of fluoropyrimidine-based therapy. In conclusion, TAS-114, a dual dUTPase/DPD inhibitor, demonstrated the potential to improve the therapeutic efficacy of fluoropyrimidine. Dual inhibition of dUTPase and DPD is a novel strategy for the advancement of oral fluoropyrimidine-based chemotherapy for cancer treatment. Mol Cancer Ther; 17(8); 1683–93. ©2018 AACR.
Data from Induced Telomere Damage to Treat Telomerase Expressing Therapy-Resistant Pediatric Brain Tumors
Authors: Sengupta Satarupa , Sobo Matthew , Lee Kyungwoo , Senthil Kumar Shiva , White Angela R. , Mender Ilgen , Fuller Christine , Chow Lionel M.L. , Fouladi Maryam , Shay Jerry W. , Drissi Rachid
Published: March 2024

Abstract
Brain tumors remain the leading cause of cancer-related deaths in children and often are associated with long-term sequelae among survivors of current therapies. Hence, there is an urgent need to identify actionable targets and to develop more effective therapies. Telomerase and telomeres play important roles in cancer, representing attractive therapeutic targets to treat children with poor-prognosis brain tumors such as diffuse intrinsic pontine glioma (DIPG), high-grade glioma (HGG), and high-risk medulloblastoma. We have previously shown that DIPG, HGG, and medulloblastoma frequently express telomerase activity. Here, we show that the telomerase-dependent incorporation of 6-thio-2′deoxyguanosine (6-thio-dG), a telomerase substrate precursor analogue, into telomeres leads to telomere dysfunction–induced foci (TIF) along with extensive genomic DNA damage, cell growth inhibition, and cell death of primary stem-like cells derived from patients with DIPG, HGG, and medulloblastoma. Importantly, the effect of 6-thio-dG is persistent even after drug withdrawal. Treatment with 6-thio-dG elicits a sequential activation of ATR and ATM pathways and induces G2–M arrest. In vivo treatment of mice bearing medulloblastoma xenografts with 6-thio-dG delays tumor growth and increases in-tumor TIFs and apoptosis. Furthermore, 6-thio-dG crosses the blood–brain barrier and specifically targets tumor cells in an orthotopic mouse model of DIPG. Together, our findings suggest that 6-thio-dG is a promising novel approach to treat therapy-resistant telomerase-positive pediatric brain tumors. Mol Cancer Ther; 17(7); 1504–14. ©2018 AACR.
Data from Combinatorial Treatment with mTOR Inhibitors and Streptozotocin Leads to Synergistic In Vitro and In Vivo Antitumor Effects in Insulinoma Cells
Authors: Bollard Julien , Patte Céline , Massoma Patrick , Goddard Isabelle , Gadot Nicolas , Benslama Noura , Hervieu Valérie , Ferraro-Peyret Carole , Cordier-Bussat Martine , Scoazec Jean-Yves , Roche Colette , Walter Thomas , Vercherat Cécile
Published: March 2024

Abstract
Streptozotocin-based chemotherapy is the first-line chemotherapy recommended for advanced pancreatic neuroendocrine tumors (pNETs), whereas targeted therapies, including mTOR inhibitors, are available in second-line treatment. Unfortunately, objective response rates to both treatments are limited. Because mTOR pathway activation, commonly observed in pNETs, has been reported as one of the major mechanisms accounting for chemoresistance, we investigated the potential benefit of mTOR inhibition combined with streptozotocin treatment in a subset of pNETs, namely insulinomas. To evaluate the potential of mTOR inhibition in combination with streptozotocin, we selected four different inhibitors acting at various levels of the pathway (everolimus: inhibition of mTORC1; MK-2206: inhibition of AKT; BKM120: inhibition of PI3K, mTORC1, and mTORC2; and BEZ235: inhibition of mTORC1 and mTORC2). Effects on cell viability and apoptosis were assessed in insulinoma cell lines INS-1E (rat) and MIN6 (mouse) in vitro and were confirmed in vivo by using a mouse model of hepatic tumor dissemination after intrasplenic xenograft. In vitro, all four combinations display synergistic effects. These combinations lead to heterogeneous mTOR pathway inhibition, in agreement with their respective target, and increased apoptosis. In vivo, tumor growth in the liver was significantly inhibited by combining streptozotocin with everolimus (P = 0.0014), BKM120 (P = 0.0092), or BEZ235 (P = 0.008) as compared to each agent alone. These results suggest that targeting the mTOR pathway in combination with streptozotocin could be of potential benefit for insulinomas and pNET patients and thus support further clinical investigations. Mol Cancer Ther; 17(1); 60–72. ©2017 AACR.
Data from The Mutational Landscape of Gastrointestinal Malignancies as Reflected by Circulating Tumor DNA
Authors: Riviere Paul , Fanta Paul T. , Ikeda Sadakatsu , Baumgartner Joel , Heestand Gregory M. , Kurzrock Razelle
Published: March 2024

Abstract
We aimed to assess the utility of a novel, noninvasive method of detecting genomic alterations in patients with gastrointestinal malignancies, i.e., the use of liquid biopsies to obtain blood-derived circulating tumor DNA (ctDNA) through an analysis of the genomic landscape of ctDNA (68 genes) from 213 patients with advanced gastrointestinal cancers. The most common cancer types were colorectal adenocarcinoma (N = 55; 26%), appendiceal adenocarcinoma (N = 46; 22%), hepatocellular carcinoma (N = 31; 15%), and pancreatic ductal adenocarcinoma (N = 25; 12%). The majority of patients (58%) had ≥1 characterized alteration (excluded variants of unknown significance). The median number of characterized alterations was 1 (range, 0–13). The number of detected alterations per patient varied between different cancer types: in hepatocellular carcinoma, 74% of patients (23/31) had ≥1 characterized alteration(s) versus 24% of appendiceal adenocarcinoma patients (11/46). The median percent ctDNA among characterized alterations was 2.50% (interquartile range, 0.76%–8.96%). Overall, 95% of patients (117/123) had distinct molecular portfolios with 143 unique characterized alterations within 56 genes. Overall, concordance rates of 96%, 94%, 95%, and 91%, respectively, were found between ctDNA and tissue biopsy (N = 105 patients) in the four most common alterations (KRAS amplification, MYC amplification, KRAS G12V, and EGFR amplification). Of 123 patients with characterized alterations, >99% (122/123; 57% of entire population tested; 122/213) had one or more alterations potentially actionable by experimental or approved drugs. These observations suggest that many patients with gastrointestinal tumors, including difficult-to-biopsy malignancies like hepatocellular cancers, frequently have discernible and theoretically pharmacologically tractable ctDNA alterations that merit further studies in prospective trials. Mol Cancer Ther; 17(1); 297–305. ©2017 AACR.
Data from Radiosensitization In Vivo by Histone Deacetylase Inhibition with No Increase in Early Normal Tissue Radiation Toxicity
Authors: Groselj Blaz , Ruan Jia-Ling , Scott Helen , Gorrill Jessica , Nicholson Judith , Kelly Jacqueline , Anbalagan Selvakumar , Thompson James , Stratford Michael R.L. , Jevons Sarah J. , Hammond Ester M. , Scudamore Cheryl L. , Kerr Martin , Kiltie Anne E.
Published: March 2024

Abstract
As the population ages, more elderly patients require radiotherapy-based treatment for their pelvic malignancies, including muscle-invasive bladder cancer, as they are unfit for major surgery. Therefore, there is an urgent need to find radiosensitizing agents minimally toxic to normal tissues, including bowel and bladder, for such patients. We developed methods to determine normal tissue toxicity severity in intestine and bladder in vivo, using novel radiotherapy techniques on a small animal radiation research platform (SARRP). The effects of panobinostat on in vivo tumor growth delay were evaluated using subcutaneous xenografts in athymic nude mice. Panobinostat concentration levels in xenografts, plasma, and normal tissues were measured in CD1-nude mice. CD1-nude mice were treated with drug/irradiation combinations to assess acute normal tissue effects in small intestine using the intestinal crypt assay, and later effects in small and large intestine at 11 weeks by stool assessment and at 12 weeks by histologic examination. In vitro effects of panobinostat were assessed by qPCR and of panobinostat, TMP195, and mocetinostat by clonogenic assay, and Western blot analysis. Panobinostat resulted in growth delay in RT112 bladder cancer xenografts but did not significantly increase acute (3.75 days) or 12 weeks' normal tissue radiation toxicity. Radiosensitization by panobinostat was effective in hypoxic bladder cancer cells and associated with class I HDAC inhibition, and protein downregulation of HDAC2 and MRE11. Pan-HDAC inhibition is a promising strategy for radiosensitization, but more selective agents may be more useful radiosensitizers clinically, resulting in fewer systemic side effects. Mol Cancer Ther; 17(2); 381–92. ©2017 AACR.

See all articles in this MCT Focus section, “Developmental Therapeutics in Radiation Oncology.”
Data from EPHA2 Is a Predictive Biomarker of Resistance and a Potential Therapeutic Target for Improving Antiepidermal Growth Factor Receptor Therapy in Colorectal Cancer
Authors: Martini Giulia , Cardone Claudia , Vitiello Pietro Paolo , Belli Valentina , Napolitano Stefania , Troiani Teresa , Ciardiello Davide , Della Corte Carminia Maria , Morgillo Floriana , Matrone Nunzia , Sforza Vincenzo , Papaccio Gianpaolo , Desiderio Vincenzo , Paul Mariel C. , Moreno-Viedma Veronica , Normanno Nicola , Rachiglio Anna Maria , Tirino Virginia , Maiello Evaristo , Latiano Tiziana Pia , Rizzi Daniele , Signoriello Giuseppe , Sibilia Maria , Ciardiello Fortunato , Martinelli Erika
Published: March 2024

Abstract
The EPHA2 tyrosine kinase receptor is implicated in tumor progression and targeted therapies resistance. We evaluated EPHA2 as a potential resistance marker to the antiepidermal growth factor receptor (EGFR) monoclonal antibody cetuximab in colorectal cancer. We studied activation of EPHA2 in a panel of human colorectal cancer cell lines sensitive or resistant to anti-EGFR drugs. The in vitro and in vivo effects of ALW-II-41-27 (an EPHA2 inhibitor) and/or cetuximab treatment were tested. Formalin-fixed paraffin-embedded tumor specimens from 82 RAS wild-type (WT) metastatic colorectal cancer patients treated with FOLFIRI + cetuximab as first-line therapy in the CAPRI-GOIM trial were assessed for EPHA2 expression by immunohistochemistry and correlated with treatment efficacy. EPHA2 was differentially activated in colorectal cancer cell lines. Combined treatment with ALW-II-41-27 plus cetuximab reverted primary and acquired resistance to cetuximab, causing cell growth inhibition, inducing apoptosis and cell-cycle G1–G2 arrest. In tumor xenograft models, upon progression to cetuximab, ALW-II-41-27 addition significantly inhibited tumor growth. EPHA2 protein expression was detected in 55 of 82 tumor samples, frequently expressed in less-differentiated and left-sided tumors. High levels of EPHA2 significantly correlated with worse progression-free survival [8.6 months; confidence interval (CI) 95%, 6.4–10.8; vs. 12.3 months; CI 95%, 10.4–14.2; P = 0.03] and with increased progression rate (29% vs. 9%, P = 0.02). A specific EPHA2 inhibitor reverts in vitro and in vivo primary and acquired resistance to anti-EGFR therapy. EPHA2 levels are significantly associated with worse outcome in patients treated with FOLFIRI + cetuximab. These results highlight EPHA2 as a potential therapeutic target in metastatic colorectal cancer.
Data from Preclinical Development of a Bispecific Antibody that Safely and Effectively Targets CD19 and CD47 for the Treatment of B-Cell Lymphoma and Leukemia
Authors: Buatois Vanessa , Johnson Zoë , Salgado-Pires Susana , Papaioannou Anne , Hatterer Eric , Chauchet Xavier , Richard Françoise , Barba Leticia , Daubeuf Bruno , Cons Laura , Broyer Lucile , D'Asaro Matilde , Matthes Thomas , LeGallou Simon , Fest Thierry , Tarte Karin , Clarke Hinojosa Robert K. , Genescà Ferrer Eulàlia , Ribera José María , Dey Aditi , Bailey Katharine , Fielding Adele K. , Eissenberg Linda , Ritchey Julie , Rettig Michael , DiPersio John F. , Kosco-Vilbois Marie H. , Masternak Krzysztof , Fischer Nicolas , Shang Limin , Ferlin Walter G.
Published: March 2024

Abstract
CD47, an ubiquitously expressed innate immune checkpoint receptor that serves as a universal “don't eat me” signal of phagocytosis, is often upregulated by hematologic and solid cancers to evade immune surveillance. Development of CD47-targeted modalities is hindered by the ubiquitous expression of the target, often leading to rapid drug elimination and hemotoxicity including anemia. To overcome such liabilities, we have developed a fully human bispecific antibody, NI-1701, designed to coengage CD47 and CD19 selectively on B cells. NI-1701 demonstrates favorable elimination kinetics with no deleterious effects seen on hematologic parameters following single or multiple administrations to nonhuman primates. Potent in vitro and in vivo activity is induced by NI-1701 to kill cancer cells across a plethora of B-cell malignancies and control tumor growth in xenograft mouse models. The mechanism affording maximal tumor growth inhibition by NI-1701 is dependent on the coengagement of CD47/CD19 on B cells inducing potent antibody-dependent cellular phagocytosis of the targeted cells. NI-1701–induced control of tumor growth in immunodeficient NOD/SCID mice was more effective than that achieved with the anti-CD20 targeted antibody, rituximab. Interestingly, a synergistic effect was seen when tumor-implanted mice were coadministered NI-1701 and rituximab leading to significantly improved tumor growth inhibition and regression in some animals. We describe herein, a novel bispecific antibody approach aimed at sensitizing B cells to become more readily phagocytosed and eliminated thus offering an alternative or adjunct therapeutic option to patients with B-cell malignancies refractory/resistant to anti-CD20–targeted therapy. Mol Cancer Ther; 17(8); 1739–51. ©2018 AACR.
Data from An Infrared Dye–Conjugated Virus-like Particle for the Treatment of Primary Uveal Melanoma
Authors: Kines Rhonda C. , Varsavsky Isabella , Choudhary Sanghamitra , Bhattacharya Debaditya , Spring Sean , McLaughlin Roger , Kang Shin J. , Grossniklaus Hans E. , Vavvas Demetrios , Monks Stephen , MacDougall John R. , de los Pinos Elisabet , Schiller John T.
Published: March 2024

Abstract
The work outlined herein describes AU-011, a novel recombinant papillomavirus-like particle (VLP) drug conjugate and its initial evaluation as a potential treatment for primary uveal melanoma. The VLP is conjugated with a phthalocyanine photosensitizer, IRDye 700DX, that exerts its cytotoxic effect through photoactivation with a near-infrared laser. We assessed the anticancer properties of AU-011 in vitro utilizing a panel of human cancer cell lines and in vivo using murine subcutaneous and rabbit orthotopic xenograft models of uveal melanoma. The specificity of VLP binding (tumor targeting), mediated through cell surface heparan sulfate proteoglycans (HSPG), was assessed using HSPG-deficient cells and by inclusion of heparin in in vitro studies. Our results provide evidence of potent and selective anticancer activity, both in vitro and in vivo. AU-011 activity was blocked by inhibiting its association with HSPG using heparin and using cells lacking surface HSPG, indicating that the tumor tropism of the VLP was not affected by dye conjugation and cell association is critical for AU-011–mediated cytotoxicity. Using the uveal melanoma xenograft models, we observed tumor uptake following intravenous (murine) and intravitreal (rabbit) administration and, after photoactivation, potent dose-dependent tumor responses. Furthermore, in the rabbit orthotopic model, which closely models uveal melanoma as it presents in the clinic, tumor treatment spared the retina and adjacent ocular structures. Our results support further clinical development of this novel therapeutic modality that might transform visual outcomes and provide a targeted therapy for the early-stage treatment of patients with this rare and life-threatening disease. Mol Cancer Ther; 17(2); 565–74. ©2017 AACR.