bluuebunny/crossref_metadata_2025 huggingface dataset:
Data from MKAD-21 Suppresses the Oncogenic Activity of the miR-21/PPP2R2A/ERK Molecular Network in Bladder Cancer
Authors: Koutsioumpa Marina , Chen Hsiao-Wang , O'Brien Neil , Koinis Filippos , Mahurkar-Joshi Swapna , Vorvis Christina , Soroosh Artin , Luo Tong , Issakhanian Shawnt , Pantuck Allan J. , Georgoulias Vassilis , Iliopoulos Dimitrios , Slamon Dennis J. , Drakaki Alexandra
Published: April 2023

Abstract
Bladder cancer represents a disease associated with significant morbidity and mortality. MiR-21 has been found to have oncogenic activity in multiple cancers, including bladder cancer, whereas inhibition of its expression suppresses tumor growth. Here, we examine the molecular network regulated by miR-21 in bladder cancer and evaluate the effects of i.v. and i.p. administration of a novel miR-21 chemical inhibitor in vivo. LNA miR-21 reduced the oncogenic potential of bladder cancer cells, whereas the MKAD-21 chemically modified antisense oligo against miR-21 dose-dependently blocked xenograft growth. I.v. administration of LNA miR-21 was more effective in suppressing tumor growth than was i.p. administration. Integration of computational and transcriptomic analyses in a panel of 28 bladder cancer lines revealed a 15-gene signature that correlates with miR-21 levels. Protein Phosphatase 2 Regulatory Subunit Balpha (PPP2R2A) was one of these 15 genes and was experimentally validated as a novel miR-21 direct target gene. Gene network and molecular analyses showed that PPP2R2A is a potent negative regulator of the ERK pathway activation and bladder cancer cell proliferation. Importantly, we show that PPP2R2A acts as a mediator of miR-21–induced oncogenic effects in bladder cancer. Integrative analysis of human bladder cancer tumors and a large panel of human bladder cancer cell lines revealed a novel 15-gene signature that correlates with miR-21 levels. Importantly, we provide evidence that PPP2R2A represents a new miR-21 direct target and regulator of the ERK pathway and bladder cancer cell growth. Furthermore, i.v. administration of the MKAD-21 inhibitor effectively suppressed tumor growth through regulation of the PPP2R2A–ERK network in mice. Mol Cancer Ther; 17(7); 1430–40. ©2018 AACR.
Data from Trastuzumab-Resistant HER2+ Breast Cancer Cells Retain Sensitivity to Poly (ADP-Ribose) Polymerase (PARP) Inhibition
Authors: Wielgos Monica E. , Zhang Zhuo , Rajbhandari Rajani , Cooper Tiffiny S. , Zeng Ling , Forero Andres , Esteva Francisco J. , Osborne C. Kent , Schiff Rachel , LoBuglio Albert F. , Nozell Susan E. , Yang Eddy S.
Published: April 2023

Abstract
HER2-targeted therapies, such as trastuzumab, have increased the survival rates of HER2+ breast cancer patients. However, despite these therapies, many tumors eventually develop resistance to these therapies. Our lab previously reported an unexpected sensitivity of HER2+ breast cancer cells to poly (ADP-ribose) polymerase inhibitors (PARPi), agents that target homologous recombination (HR)–deficient tumors, independent of a DNA repair deficiency. In this study, we investigated whether HER2+ trastuzumab-resistant (TR) breast cancer cells were susceptible to PARPi and the mechanism behind PARPi induced cytotoxicity. We demonstrate that the PARPi ABT-888 (veliparib) decreased cell survival in vitro and tumor growth in vivo of HER2+ TR breast cancer cells. PARP-1 siRNA confirmed that cytotoxicity was due, in part, to PARP-1 inhibition. Furthermore, PARP-1 silencing had variable effects on the expression of several NF-κB–regulated genes. In particular, silencing PARP-1 inhibited NF-κB activity and reduced p65 binding at the IL8 promoter, which resulted in a decrease in IL8 mRNA and protein expression. Our results provide insight in the potential mechanism by which PARPi induces cytotoxicity in HER2+ breast cancer cells and support the testing of PARPi in patients with HER2+ breast cancer resistant to trastuzumab. Mol Cancer Ther; 17(5); 921–30. ©2018 AACR.
Data from Unraveling the Interaction between Carboxylesterase 1c and the Antibody–Drug Conjugate SYD985: Improved Translational PK/PD by Using Ces1c Knockout Mice
Authors: Ubink Ruud , Dirksen Eef H.C. , Rouwette Myrthe , Bos Ebo S. , Janssen Ingrid , Egging David F. , Loosveld Eline M. , van Achterberg Tanja A. , Berentsen Kim , van der Lee Miranda M.C. , Bichat Francis , Raguin Olivier , van der Vleuten Monique A.J. , Groothuis Patrick G. , Dokter Wim H.A.
Published: April 2023

Abstract
Carboxylesterase 1c (CES1c) is responsible for linker-drug instability and poor pharmacokinetics (PK) of several antibody–drug conjugates (ADC) in mice, but not in monkeys or humans. Preclinical development of these ADCs could be improved if the PK in mice would more closely resemble that of humans and is not affected by an enzyme that is irrelevant for humans. SYD985, a HER2-targeting ADC based on trastuzumab and linker-drug vc-seco-DUBA, is also sensitive to CES1c. In the present studies, we first focused on the interaction between CES1c and SYD985 by size- exclusion chromatography, Western blotting, and LC/MS-MS analysis, using recombinant CES1c and plasma samples. Intriguingly, CES1c activity not only results in release of the active toxin DUBA but also in formation of a covalent bond between CES1c and the linker of vc-seco-DUBA. Mass spectrometric studies enabled identification of the CES1c cleavage site on the linker-drug and the structure of the CES1c adduct. To assess the in vivo impact, CES1c−/− SCID mice were generated that showed stable PK for SYD985, comparable to that in monkeys and humans. Patient-derived xenograft (PDX) studies in these mice showed enhanced efficacy compared with PDX studies in CES1c+/+ mice and provided a more accurate prediction of clinical efficacy of SYD985, hence delivering better quality data. It seems reasonable to assume that CES1c−/− SCID mice can increase quality in ADC development much broader for all ADCs that carry linker-drugs susceptible to CES1c, without the need of chemically modifying the linker-drug to specifically increase PK in mice. Mol Cancer Ther; 17(11); 2389–98. ©2018 AACR.
Data from Immune Effector Functions of Human IgG2 Antibodies against EGFR
Authors: Rösner Thies , Kahle Steffen , Montenegro Francesca , Matlung Hanke L. , Jansen J.H. Marco , Evers Mitchell , Beurskens Frank , Leusen Jeanette H.W. , van den Berg Timo K. , Valerius Thomas
Published: April 2023

Abstract
Three FDA-approved epidermal growth factor receptor (EGFR) antibodies (cetuximab, panitumumab, necitumumab) are clinically available to treat patients with different types of cancers. Interestingly, panitumumab is of human IgG2 isotype, which is often considered to have limited immune effector functions. Unexpectedly, our studies unraveled that human IgG2 antibodies against EGFR mediated effective CDC when combined with another noncross-blocking EGFR antibody. This second antibody could be of human IgG1 or IgG2 isotype. Furthermore, EGFR antibodies of human IgG2 isotype were highly potent in recruiting myeloid effector cells such as M1 macrophages and PMN for tumor cell killing by ADCC. Tumor cell killing by PMN was more effective with IgG2 than with IgG1 antibodies if tumor cells expressed lower levels of EGFR. Additionally, lower expression levels of the “don′t eat me” molecule CD47 on tumor cells enabled ADCC also by M2 macrophages, and improved PMN and macrophage-mediated ADCC. A TCGA enquiry revealed broadly varying CD47 expression levels across different solid tumor types. Together, these results demonstrate that human IgG2 antibodies against EGFR can promote significant Fc-mediated effector functions, which may contribute to their clinical efficacy. The future challenge will be to identify clinical situations in which myeloid effector cells can optimally contribute to antibody efficacy.
Data from Inhibition of BMI1, a Therapeutic Approach in Endometrial Cancer
Authors: Buechel Megan , Dey Anindya , Dwivedi Shailendra Kumar Dhar , Crim Aleia , Ding Kai , Zhang Roy , Mukherjee Priyabrata , Moore Kathleen N. , Cao Liangxian , Branstrom Arthur , Weetall Marla , Baird John , Bhattacharya Resham
Published: April 2023

Abstract
With rising incidence rates, endometrial cancer is one of the most common gynecologic malignancies in the United States. Although surgery provides significant survival benefit to early-stage patients, those with advanced or recurrent metastatic disease have a dismal prognosis. Limited treatment options include chemotherapy and radiotherapy. Hence, there is a compelling need for developing molecularly targeted therapy. Here, we show that the polycomb ring finger protein BMI1, also known as a stem cell factor, is significantly overexpressed in endometrial cancer cell lines, endometrial cancer patient tissues as well as in nonendometrioid histologies and associated with poor overall survival. PTC-028, a second-generation inhibitor of BMI1 function, decreases invasion of endometrial cancer cells and potentiates caspase-dependent apoptosis, while normal cells with minimal expression of BMI1 remain unaffected. In an aggressive uterine carcinosarcoma xenograft model, single-agent PTC-028 significantly delayed tumor growth and increased tumor doubling time compared with the standard carboplatin/paclitaxel therapy. Therefore, anti-BMI1 strategies may represent a promising targeted approach in patients with advanced or recurrent endometrial cancer, a population where treatment options are limited. Mol Cancer Ther; 17(10); 2136–43. ©2018 AACR.
Data from A Simple Three-dimensional Hydrogel Platform Enables Ex Vivo Cell Culture of Patient and PDX Tumors for Assaying Their Response to Clinically Relevant Therapies
Authors: Hribar Kolin C. , Wheeler Christopher J. , Bazarov Alexey , Varshneya Kunal , Yamada Ryosuke , Buckley Padraig , Patil Chirag G.
Published: April 2023

Abstract
A cell culture platform that enables ex vivo tissue growth from patients or patient-derived xenograft (PDX) models and assesses sensitivity to approved therapies (e.g., temozolomide) in a clinically relevant time frame would be very useful in translational research and personalized medicine. Here, we present a novel three-dimensional (3D) ECM hydrogel system, VersaGel, for assaying ex vivo growth and therapeutic response with standard image microscopy. Specifically, multicellular spheroids deriving from either 5 patients with glioblastoma (GBM) or a renal cell carcinoma (RCC) PDX model were incorporated into VersaGel and treated with temozolomide and several other therapies, guided by the most recent advances in GBM treatment. RCC ex vivo tissue displayed invasive phenotypes in conditioned media. For the GBM patient tumor testing, all five clinical responses were predicted by the results of our 3D-temozolomide assay. In contrast, the MTT assay found no response to temozolomide regardless of the clinical outcome, and moreover, basement membrane extract failed to predict the 2 patient responders. Finally, 1 patient was tested with repurposed drugs currently being administered in GBM clinical trials. Interestingly, IC50s were lower than Cmax for crizotinib and chloroquine, but higher for sorafenib. In conclusion, a novel hydrogel platform, VersaGel, enables ex vivo tumor growth of patient and PDX tissue and offers insight into patient response to clinically relevant therapies. We propose a novel 3D hydrogel platform, VersaGel, to grow ex vivo tissue (patient and PDX) and assay therapeutic response using time-course image analysis.
Data from Targeting the IGF1R/PI3K/AKT Pathway Sensitizes Ewing Sarcoma to BET Bromodomain Inhibitors
Authors: Loganathan Sudan N. , Tang Nan , Holler Albert E. , Wang Nenghui , Wang Jialiang
Published: April 2023

Abstract
Inhibitors of the bromodomain and extra-terminal domain (BET) family proteins modulate EWS-FLI1 activities in Ewing sarcoma. However, the efficacy of BET inhibitors as a monotherapy was moderate and transient in preclinical models. The objective of this study was to identify the mechanisms mediating intrinsic resistance to BET inhibitors and develop more effective combination treatments for Ewing sarcoma. Using a panel of Ewing sarcoma cell lines and patient-derived xenograft lines (PDX), we demonstrated that IGF1R inhibitors synergistically increased sensitivities to BET inhibitors and induced potent apoptosis when combined with BET inhibitors. Constitutively activated AKT significantly protected Ewing sarcoma cells against BET inhibitors, suggesting that IGF1R regulates responsiveness to BET inhibitors mainly through the PI3K/AKT pathway. Although two Ewing sarcoma cell lines were resistant to IGF1R inhibitors, they retained synergistic response to a combination of BET inhibitors and mTOR inhibitors, suggesting that BET proteins, when IGF1R is not functional, cross-talk with its downstream molecules. Furthermore, the combination of a BET inhibitor and an IGF1R inhibitor induced potent and durable response in xenograft tumors, whereas either agent alone was less effective. Taken together, our results suggest that IGF1R and the downstream PI3K/AKT/mTOR kinase cascade mediate intrinsic resistance to BET inhibitors in Ewing sarcoma. These results provide the proof-of-concept for combining BET inhibitors with agents targeting the IGF1R pathway for treating advanced Ewing sarcoma.
Data from Small Molecule–Mediated Activation of RAS Elicits Biphasic Modulation of Phospho-ERK Levels that Are Regulated through Negative Feedback on SOS1
Authors: Howes Jennifer E. , Akan Denis T. , Burns Michael C. , Rossanese Olivia W. , Waterson Alex G. , Fesik Stephen W.
Published: April 2023

Abstract
Oncogenic mutation of RAS results in aberrant cellular signaling and is responsible for more than 30% of all human tumors. Therefore, pharmacologic modulation of RAS has attracted great interest as a therapeutic strategy. Our laboratory has recently discovered small molecules that activate Son of Sevenless (SOS)–catalyzed nucleotide exchange on RAS and inhibit downstream signaling. Here, we describe how pharmacologically targeting SOS1 induced biphasic modulation of RAS-GTP and ERK phosphorylation levels, which we observed in a variety of cell lines expressing different RAS-mutant isoforms. We show that compound treatment caused an increase in phosphorylation at ERK consensus motifs on SOS1 that was not observed with the expression of a non-phosphorylatable S1178A SOS1 mutant or after pretreatment with an ERK inhibitor. Phosphorylation at S1178 on SOS1 is known to inhibit the association between SOS1 and GRB2 and disrupt SOS1 membrane localization. Consistent with this, we show that wild-type SOS1 and GRB2 dissociated in a time-dependent fashion in response to compound treatment, and conversely, this interaction was enhanced with the expression of an S1178A SOS1 mutant. Furthermore, in cells expressing either S1178A SOS1 or a constitutively membrane-bound CAAX box tagged SOS1 mutant, we observed elevated RAS-GTP levels over time in response to compound, as compared with the biphasic changes in RAS-GTP exhibited in cells expressing wild-type SOS1. These results suggest that small molecule targeting of SOS1 can elicit a biphasic modulation of RAS-GTP and phospho-ERK levels through negative feedback on SOS1 that regulates the interaction between SOS1 and GRB2. Mol Cancer Ther; 17(5); 1051–60. ©2018 AACR.
Data from Impact of the Anticancer Drug NT157 on Tyrosine Kinase Signaling Networks
Authors: Su Shih-Ping , Flashner-Abramson Efrat , Klein Shoshana , Gal Mor , Lee Rachel S. , Wu Jianmin , Levitzki Alexander , Daly Roger J.
Published: April 2023

Abstract
The small-molecule drug NT157 has demonstrated promising efficacy in preclinical models of a number of different cancer types, reflecting activity against both cancer cells and the tumor microenvironment. Two known mechanisms of action are degradation of insulin receptor substrates (IRS)-1/2 and reduced Stat3 activation, although it is possible that others exist. To interrogate the effects of this drug on cell signaling pathways in an unbiased manner, we have undertaken mass spectrometry–based global tyrosine phosphorylation profiling of NT157-treated A375 melanoma cells. Bioinformatic analysis of the resulting dataset resolved 5 different clusters of tyrosine-phosphorylated peptides that differed in the directionality and timing of response to drug treatment over time. The receptor tyrosine kinase AXL exhibited a rapid decrease in phosphorylation in response to drug treatment, followed by proteasome-dependent degradation, identifying an additional potential target for NT157 action. However, NT157 treatment also resulted in increased activation of p38 MAPK α and γ, as well as the JNKs and specific Src family kinases. Importantly, cotreatment with the p38 MAPK inhibitor SB203580 attenuated the antiproliferative effect of NT157, while synergistic inhibition of cell proliferation was observed when NT157 was combined with a Src inhibitor. These findings provide novel insights into NT157 action on cancer cells and highlight how globally profiling the impact of a specific drug on cellular signaling networks can identify effective combination treatments. Mol Cancer Ther; 17(5); 931–42. ©2018 AACR.
Data from Selective and Concentrated Accretion of SN-38 with a CEACAM5-Targeting Antibody–Drug Conjugate (ADC), Labetuzumab Govitecan (IMMU-130)
Authors: Sharkey Robert M. , Govindan Serengulam V. , Cardillo Thomas M. , Donnell Jennifer , Xia Jing , Rossi Edmund A. , Chang Chien-Hsing , Goldenberg David M.
Published: April 2023

Abstract
Labetuzumab govitecan (IMMU-130), an antibody–drug conjugate (ADC) with an average of 7.6 SN-38/IgG, was evaluated for its potential to enhance delivery of SN-38 to human colonic tumor xenografts. Mice bearing LS174T or GW-39 human colonic tumor xenografts were injected with irinotecan or IMMU-130 (SN-38 equivalents ∼500 or ∼16 μg, respectively). Serum and homogenates of tumors, liver, and small intestine were extracted, and SN-38, SN-38G (glucuronidated SN-38), and irinotecan concentrations determined by reversed-phase HPLC. Irinotecan cleared quickly from serum, with only 1% to 2% injected dose/mL after 5 minutes; overall, approximately 20% was converted to SN-38 and SN-38G. At 1 hour with IMMU-130, 45% to 63% injected dose/mL of the SN-38 was in the serum, with >90% bound to the ADC over 3 days, and with low levels of SN-38G. Total SN-38 levels decreased more quickly than the IgG, confirming a gradual SN-38 release from the ADC. AUC analysis found that SN-38 levels were approximately 11- and 16-fold higher in LS174T and GW-39 tumors, respectively, in IMMU-130–treated animals. This delivery advantage is amplified >30-fold when normalized to SN-38 equivalents injected for each product. Levels of SN-38 and SN-38G were appreciably lower in the liver and small intestinal contents in animals given IMMU-130. On the basis of the SN-38 equivalents administered, IMMU-130 potentially delivers >300-fold more SN-38 to CEA-producing tumors compared with irinotecan, while also reducing levels of SN-38 and SN-38G in normal tissues. These observations are consistent with preclinical and clinical data showing efficacy and improved safety. Mol Cancer Ther; 17(1); 196–203. ©2017 AACR.
Data from JQ1 Induces DNA Damage and Apoptosis, and Inhibits Tumor Growth in a Patient-Derived Xenograft Model of Cholangiocarcinoma
Authors: Garcia Patrick L. , Miller Aubrey L. , Gamblin Tracy L. , Council Leona N. , Christein John D. , Arnoletti J. Pablo , Heslin Marty J. , Reddy Sushanth , Richardson Joseph H. , Cui Xiangqin , van Waardenburg Robert C.A.M. , Bradner James E. , Yang Eddy S. , Yoon Karina J.
Published: April 2023

Abstract
Cholangiocarcinoma (CCA) is a fatal disease with a 5-year survival of <30%. For a majority of patients, chemotherapy is the only therapeutic option, and virtually all patients relapse. Gemcitabine is the first-line agent for treatment of CCA. Patients treated with gemcitabine monotherapy survive ∼8 months. Combining this agent with cisplatin increases survival by ∼3 months, but neither regimen produces durable remissions. The molecular etiology of this disease is poorly understood. To facilitate molecular characterization and development of effective therapies for CCA, we established a panel of patient-derived xenograft (PDX) models of CCA. We used two of these models to investigate the antitumor efficacy and mechanism of action of the bromodomain inhibitor JQ1, an agent that has not been evaluated for the treatment of CCA. The data show that JQ1 suppressed the growth of the CCA PDX model CCA2 and demonstrate that growth suppression was concomitant with inhibition of c-Myc protein expression. A second model (CCA1) was JQ1-insensitive, with tumor progression and c-Myc expression unaffected by exposure to this agent. Also selective to CCA2 tumors, JQ1 induced DNA damage and apoptosis and downregulated multiple c-Myc transcriptional targets that regulate cell-cycle progression and DNA repair. These findings suggest that c-Myc inhibition and several of its transcriptional targets may contribute to the mechanism of action of JQ1 in this tumor type. We conclude that BET inhibitors such as JQ1 warrant further investigation for the treatment of CCA. Mol Cancer Ther; 17(1); 107–18. ©2017 AACR.
Data from Development of MGD007, a gpA33 x CD3-Bispecific DART Protein for T-Cell Immunotherapy of Metastatic Colorectal Cancer
Authors: Moore Paul A. , Shah Kalpana , Yang Yinhua , Alderson Ralph , Roberts Penny , Long Vatana , Liu Daorong , Li Jonathan C. , Burke Steve , Ciccarone Valentina , Li Hua , Fieger Claudia B. , Hooley Jeff , Easton Ann , Licea Monica , Gorlatov Sergey , King Kathy L. , Young Peter , Adami Arash , Loo Deryk , Chichili Gurunadh R. , Liu Liqin , Smith Douglas H. , Brown Jennifer G. , Chen Francine Z. , Koenig Scott , Mather Jennie , Bonvini Ezio , Johnson Syd
Published: April 2023

Abstract
We have developed MGD007 (anti-glycoprotein A33 x anti-CD3), a DART protein designed to redirect T cells to target gpA33 expressing colon cancer. The gpA33 target was selected on the basis of an antibody-based screen to identify cancer antigens universally expressed in both primary and metastatic colorectal cancer specimens, including putative cancer stem cell populations. MGD007 displays the anticipated-bispecific binding properties and mediates potent lysis of gpA33-positive cancer cell lines, including models of colorectal cancer stem cells, through recruitment of T cells. Xenograft studies showed tumor growth inhibition at doses as low as 4 μg/kg. Both CD8 and CD4 T cells mediated lysis of gpA33-expressing tumor cells, with activity accompanied by increases in granzyme and perforin. Notably, suppressive T-cell populations could also be leveraged to mediate lysis of gpA33-expressing tumor cells. Concomitant with CTL activity, both T-cell activation and expansion are observed in a gpA33-dependent manner. No cytokine activation was observed with human PBMC alone, consistent with the absence of gpA33 expression on peripheral blood cell populations. Following prolonged exposure to MGD007 and gpA33 positive tumor cells, T cells express PD-1 and LAG-3 and acquire a memory phenotype but retain ability to support potent cell killing. In cynomolgus monkeys, 4 weekly doses of 100 μg/kg were well tolerated, with prolonged PK consistent with that of an Fc-containing molecule. Taken together, MGD007 displays potent activity against colorectal cancer cells consistent with a mechanism of action endowed in its design and support further investigation of MGD007 as a potential novel therapeutic treatment for colorectal cancer. Mol Cancer Ther; 17(8); 1761–72. ©2018 AACR.
Data from Antitumor Activity of MEDI3726 (ADCT-401), a Pyrrolobenzodiazepine Antibody–Drug Conjugate Targeting PSMA, in Preclinical Models of Prostate Cancer
Authors: Cho Song , Zammarchi Francesca , Williams David G. , Havenith Carin E.G. , Monks Noel R. , Tyrer Peter , D'Hooge Francois , Fleming Ryan , Vashisht Kapil , Dimasi Nazzareno , Bertelli Francois , Corbett Simon , Adams Lauren , Reinert Halla W. , Dissanayake Sandamali , Britten Charles E. , King Wanda , Dacosta Karma , Tammali Ravinder , Schifferli Kevin , Strout Patrick , Korade Martin , Masson Hinrichs Mary Jane , Chivers Simon , Corey Eva , Liu He , Kim Sae , Bander Neil H. , Howard Philip W. , Hartley John A. , Coats Steve , Tice David A. , Herbst Ronald , van Berkel Patrick H.
Published: April 2023

Abstract
Prostate-specific membrane antigen (PSMA) is a membrane-bound glutamate carboxypeptidase that is highly expressed in nearly all prostate cancers with the highest expression in metastatic castration-resistant prostate cancer (mCRPC). The prevalence of increased surface expression and constitutive internalization of PSMA make it an attractive target for an antibody–drug conjugate (ADC) approach to treating patients with mCRPC. MEDI3726 (previously known as ADCT-401) is an ADC consisting of an engineered version of the anti-PSMA antibody J591 site specifically conjugated to the pyrrolobenzodiazepine (PBD) dimer tesirine. MEDI3726 specifically binds the extracellular domain of PSMA and, once internalized, releases the PBD dimer to crosslink DNA and trigger cell death. In vitro, MEDI3726 demonstrated potent and specific cytotoxicity in a panel of PSMA-positive prostate cancer cell lines, consistent with internalization and DNA interstrand crosslinking. In vivo, MEDI3726 showed robust antitumor activity against the LNCaP and the castration-resistant CWR22Rv1 prostate cancer cell line xenografts. MEDI3726 also demonstrated durable antitumor activity in the PSMA-positive human prostate cancer patient–derived xenograft (PDX) LuCaP models. This activity correlated with increased phosphorylated Histone H2AX in tumor xenografts treated with MEDI3726. MEDI3726 is being evaluated in a phase I clinical trial as a treatment for patients with metastatic castrate-resistant prostate cancer (NCT02991911). Mol Cancer Ther; 17(10); 2176–86. ©2018 AACR.
Data from The Unfolded Protein Response: A Novel Therapeutic Target for Poor Prognostic BRAF Mutant Colorectal Cancer
Authors: Forsythe Nicholas , Refaat Alaa , Javadi Arman , Khawaja Hajrah , Weir Jessica-Anne , Emam Heba , Allen Wendy L. , Burkamp Frank , Popovici Vlad , Jithesh Puthen V. , Isella Claudio , Labonte Melissa J. , Mills Ian G. , Johnston Patrick G. , Van Schaeybroeck Sandra
Published: April 2023

Abstract
BRAFV600E mutations occur in ∼10% of colorectal cancer cases, are associated with poor survival, and have limited responses to BRAF/MEK inhibition with or without EGFR inhibition. There is an unmet need to understand the biology of poor prognostic BRAFMT colorectal cancer. We have used differential gene expression and pathway analyses of untreated stage II and stage III BRAFMT (discovery set: n = 31; validation set: n = 26) colorectal cancer, and an siRNA screen to characterize the biology underpinning the BRAFMT subgroup with poorest outcome. These analyses identified the unfolded protein response (UPR) as a novel and druggable pathway associated with the BRAFMT colorectal cancer subgroup with poorest outcome. We also found that oncogenic BRAF drives endoplasmic reticulum (ER) stress and UPR pathway activation through MEK/ERK. Furthermore, inhibition of GRP78, the master regulator of the UPR, using siRNA or small molecule inhibition, resulted in acute ER stress and apoptosis, in particular in BRAFMT colorectal cancer cells. In addition, dual targeting of protein degradation using combined Carfilzomib (proteasome inhibitor) and ACY-1215 (HDAC6-selective inhibitor) treatment resulted in marked accumulation of protein aggregates, acute ER stress, apoptosis, and therapeutic efficacy in BRAFMT in vitro and xenograft models. Mechanistically, we found that the apoptosis following combined Carfilzomib/ACY-1215 treatment is mediated through increased CHOP expression. Taken together, our findings indicate that oncogenic BRAF induces chronic ER stress and that inducers of acute ER stress could be a novel treatment strategy for poor prognostic BRAFMT colorectal cancer. Mol Cancer Ther; 17(6); 1280–90. ©2018 AACR.
Data from p110α Inhibition Overcomes Stromal Cell–Mediated Ibrutinib Resistance in Mantle Cell Lymphoma
Authors: Guan Jiyu , Huang Dan , Yakimchuk Konstantin , Okret Sam
Published: April 2023

Abstract
Acquired resistance to cancer drugs is common, also for modern targeted drugs like the Bruton tyrosine kinase (BTK) inhibitor ibrutinib, a new drug approved for the treatment of the highly aggressive and relapsing mantle cell lymphoma (MCL). The tumor microenvironment often impacts negatively on drug response. Here, we demonstrate that stromal cells protect MCL cells from ibrutinib-induced apoptosis and support MCL cell regrowth after drug removal by impairing ibrutinib-mediated downregulation of PI3K/AKT signaling. Importantly, the stromal cell–mediated ibrutinib resistance was overcome in vitro by inhibiting AKT activity using the PI3K catalytic p110α subunit–specific inhibitor BYL719. This was seen both for MCL cell lines and primary MCL cells. Furthermore, inhibition of p110α activity by BYL719 potentiated the ability of ibrutinib to inhibit MCL tumor growth in vivo in a mouse xenograft model. The stromal cell–mediated ibrutinib resistance was found to be due to a direct interaction with MCL cells and involves the integrin VLA-4, as disrupting stromal cell–MCL cell interaction using a VLA-4 blocking antibody abrogated the ibrutinib resistance. This suggests that combined treatment with ibrutinib and a p110α inhibitor, alternatively by disrupting stromal cell–MCL cell interaction, may be a promising therapeutic strategy to overcome stromal cell–mediated ibrutinib resistance in MCL. Mol Cancer Ther; 17(5); 1090–100. ©2018 AACR.
Data from Lycorine Promotes Autophagy and Apoptosis via TCRP1/Akt/mTOR Axis Inactivation in Human Hepatocellular Carcinoma
Authors: Yu Haiyang , Qiu Yuling , Pang Xu , Li Jian , Wu Song , Yin Shuangshuang , Han Lifeng , Zhang Yi , Jin Chengyun , Gao Xiumei , Hu Wenwei , Wang Tao
Published: April 2023

Abstract
Lycorine is a multifunctional bioactive compound, and it possesses potential anticancer activities. However, little is known about the underlying mechanism. In this research, we have found that lycorine significantly induces the apoptotic and autophagic capacities of hepatocellular carcinoma (HCC) cells in vitro and in vivo. Treatment with specific autophagy inhibitor (3-methyladenine/Bafilomycin A1) or knockdown of LC-3B/Atg5 by siRNA drastically enhances the apoptotic cell death effect by facilitating the switch from autophagy to apoptosis. Molecular validation mechanistically demonstrates that lycorine-induced apoptosis and autophagy in HCC cells is associated with decreased protein levels of tongue cancer resistance–associated protein 1 (TCRP1), and we further find that inhibition of TCRP1 decreases phosphorylation level of Akt and represses Akt/mTOR signaling. Finally, lycorine-induced apoptosis and autophagy suppress the growth of xenograft hepatocellular tumors without remarkable toxicity. Our results elucidate a novel molecular mechanism whereby lycorine promotes apoptosis and autophagy through the TCRP1/Akt/mTOR pathway in HCC. Our results reveal that lycorine might be a potential therapeutic agent for the treatment of HCC. Mol Cancer Ther; 16(12); 2711–23. ©2017 AACR.
Data from RON Receptor Tyrosine Kinase as a Therapeutic Target for Eradication of Triple-Negative Breast Cancer: Efficacy of Anti-RON ADC Zt/g4-MMAE
Authors: Suthe Sreedhar Reddy , Yao Hang-Ping , Weng Tian-Hao , Hu Chen-Yu , Feng Liang , Wu Zhi-Gang , Wang Ming-Hai
Published: April 2023

Abstract
Triple-negative breast cancer (TNBC) is a highly diverse group of malignant neoplasia with poor outcome. Currently, the lack of effective therapy has fostered a major effort to discover new targets to treat this malignant cancer. Here we identified the RON receptor tyrosine kinase as a therapeutic target for potential TNBC treatment. We analyzed RON expression in 168 primary TNBC samples via tissue microarray using anti-RON IHC staining and demonstrated that RON was widely expressed in 76.8% TNBC samples with overexpression in 76 cases (45.2%). These results provide the molecular basis to target RON for TNBC therapy. To this end, anti-RON monoclonal antibody Zt/g4-drug monomethyl auristatin E conjugate (Zt/g4-MMAE) was developed with a drug to antibody ratio of 3.29 and tested in a panel of TNBC cell lines with different phenotypes. In vitro, Zt/g4-MMAE rapidly induced RON internalization, resulted in cell-cycle arrest followed by massive cell death. The calculated IC50 values ranged from 0.06 to 3.46 μg/mL dependent on individual TNBC cell lines tested. Zt/g4-MMAE also effectively killed TNBC stem-like cells with RON+/CD44+/CD24− phenotypes and RON-negative TNBC cells through the bystander effect. In vivo, Zt/g4-MMAE at 10 mg/kg in a Q12 × 2 regimen completely eradicated TNBC xenografts without the regrowth of xenograft tumors. In conclusion, increased RON expression is a pathogenic feature in primary TNBC samples. Zt/g4-MMAE is highly effective in eradicating TNBC xenografts in preclinical models. These findings lay the foundation for using anti-RON Zt/g4-MMAE in clinical trials as a novel strategy for TNBC treatment.
Data from Oleanolic Acid Inhibits Epithelial–Mesenchymal Transition of Hepatocellular Carcinoma by Promoting iNOS Dimerization
Authors: Wang Hongzhi , Zhong Weilong , Zhao Jianmin , Zhang Heng , Zhang Qiang , Liang Yuan , Chen Shuang , Liu Huijuan , Zong Shumin , Tian Yixuan , Zhou Honggang , Sun Tao , Liu Yanrong , Yang Cheng
Published: April 2023

Abstract
Oleanolic acid exhibits extensive pharmacologic activities and takes significant antitumor effects. Its pharmacologic mechanism, however, still remained to be further clarified. In this study, we demonstrated that oleanolic acid attenuated the migration and invasion abilities, resulting in the suppression of the epithelial–mesenchymal transition (EMT) process in liver cancer cells, and inhibited the tumor growth of the peritoneal lymphocytes–bearing mice. We further proved that inducible nitric oxide synthase (iNOS) may be the potential target of oleanolic acid. We confirmed that oleanolic acid could promote the dimerization of iNOS, activating it, and subsequently increasing the production of nitric oxide. Further experiments indicated that oleanolic acid promoted the nitration of specific proteins and consequently suppressed their EMT-related biological functions. Furthermore, it has been confirmed that oleanolic acid enhanced the antitumor effects of regorafenib in liver cancer treatment. These results deepened our understanding of the pharmacologic mechanism of the antitumor effect oleanolic acid, and the importance of nitric oxide synthetase as a therapeutic target for liver cancer treatment.
Data from Potent Immune Modulation by MEDI6383, an Engineered Human OX40 Ligand IgG4P Fc Fusion Protein
Authors: Oberst Michael D. , Augé Catherine , Morris Chad , Kentner Stacy , Mulgrew Kathy , McGlinchey Kelly , Hair James , Hanabuchi Shino , Du Qun , Damschroder Melissa , Feng Hui , Eck Steven , Buss Nicholas , de Haan Lolke , Pierce Andrew J. , Park Haesun , Sylwester Andrew , Axthelm Michael K. , Picker Louis , Morris Nicholas P. , Weinberg Andrew , Hammond Scott A.
Published: April 2023

Abstract
Ligation of OX40 (CD134, TNFRSF4) on activated T cells by its natural ligand (OX40L, CD252, TNFSF4) enhances cellular survival, proliferation, and effector functions such as cytokine release and cellular cytotoxicity. We engineered a recombinant human OX40L IgG4P Fc fusion protein termed MEDI6383 that assembles into a hexameric structure and exerts potent agonist activity following engagement of OX40. MEDI6383 displayed solution-phase agonist activity that was enhanced when the fusion protein was clustered by Fc gamma receptors (FcγRs) on the surface of adjacent cells. The resulting costimulation of OX40 on T cells induced NFκB promoter activity in OX40-expressing T cells and induced Th1-type cytokine production, proliferation, and resistance to regulatory T cell (Treg)-mediated suppression. MEDI6383 enhanced the cytolytic activity of tumor-reactive T cells and reduced tumor growth in the context of an alloreactive human T cell:tumor cell admix model in immunocompromised mice. Consistent with the role of OX40 costimulation in the expansion of memory T cells, MEDI6383 administered to healthy nonhuman primates elicited peripheral blood CD4 and CD8 central and effector memory T-cell proliferation as well as B-cell proliferation. Together, these results suggest that OX40 agonism has the potential to enhance antitumor immunity in human malignancies. Mol Cancer Ther; 17(5); 1024–38. ©2018 AACR.
Data from Drug-Sensitivity Screening and Genomic Characterization of 45 HPV-Negative Head and Neck Carcinoma Cell Lines for Novel Biomarkers of Drug Efficacy
Authors: Lepikhova Tatiana , Karhemo Piia-Riitta , Louhimo Riku , Yadav Bhagwan , Murumägi Astrid , Kulesskiy Evgeny , Kivento Mikko , Sihto Harri , Grénman Reidar , Syrjänen Stina M. , Kallioniemi Olli , Aittokallio Tero , Wennerberg Krister , Joensuu Heikki , Monni Outi
Published: April 2023

Abstract
There is an unmet need for effective targeted therapies for patients with advanced head and neck squamous cell carcinoma (HNSCC). We correlated gene expression, gene copy numbers, and point mutations in 45 human papillomavirus–negative HNSCC cell lines with the sensitivity to 220 anticancer drugs to discover predictive associations to genetic alterations. The drug response profiles revealed diverse efficacy of the tested drugs across the cell lines. Several genomic abnormalities and gene expression differences were associated with response to mTOR, MEK, and EGFR inhibitors. NOTCH1 and FAT1 were the most commonly mutated genes after TP53 and also showed some association with response to MEK and/or EGFR inhibitors. MYC amplification and FAM83H overexpression associated with sensitivity to EGFR inhibitors, and PTPRD deletion with poor sensitivity to MEK inhibitors. The connection between high FAM83H expression and responsiveness to the EGFR inhibitor erlotinib was validated by gene silencing and from the data set at the Cancer Cell Line Encyclopedia. The data provide several novel genomic alterations that associated to the efficacy of targeted drugs in HNSCC. These findings require further validation in experimental models and clinical series. Mol Cancer Ther; 17(9); 2060–71. ©2018 AACR.
Data from Simultaneous Targeting of Two Distinct Epitopes on MET Effectively Inhibits MET- and HGF-Driven Tumor Growth by Multiple Mechanisms
Authors: Grandal Michael M. , Havrylov Serhiy , Poulsen Thomas T. , Koefoed Klaus , Dahlman Anna , Galler Gunther R. , Conrotto Paolo , Collins Sara , Eriksen Karsten W. , Kaufman Dafna , Woude George F.Vande , Jacobsen Helle J. , Horak Ivan D. , Kragh Michael , Lantto Johan , Bouquin Thomas , Park Morag , Pedersen Mikkel W.
Published: April 2023

Abstract
Increased MET activity is linked with poor prognosis and outcome in several human cancers currently lacking targeted therapies. Here, we report on the characterization of Sym015, an antibody mixture composed of two humanized IgG1 antibodies against nonoverlapping epitopes of MET. Sym015 was selected by high-throughput screening searching for antibody mixtures with superior growth-inhibitory activity against MET-dependent cell lines. Synergistic inhibitory activity of the antibodies comprising Sym015 was observed in several cancer cell lines harboring amplified MET locus and was confirmed in vivo. Sym015 was found to exert its activity via multiple mechanisms. It disrupted interaction of MET with the HGF ligand and prompted activity-independent internalization and degradation of the receptor. In addition, Sym015 induced high levels of CDC and ADCC in vitro. The importance of these effector functions was confirmed in vivo using an Fc-effector function–attenuated version of Sym015. The enhanced effect of the two antibodies in Sym015 on both MET degradation and CDC and ADCC is predicted to render Sym015 superior to single antibodies targeting MET. Our results demonstrate strong potential for use of Sym015 as a therapeutic antibody mixture for treatment of MET-driven tumors. Sym015 is currently being tested in a phase I dose escalation clinical trial (NCT02648724). Mol Cancer Ther; 16(12); 2780–91. ©2017 AACR.
Data from Evaluating the Mechanism and Therapeutic Potential of PTC-028, a Novel Inhibitor of BMI-1 Function in Ovarian Cancer
Authors: Dey Anindya , Xiong Xunhao , Crim Aleia , Dwivedi Shailendra Kumar Dhar , Mustafi Soumyajit Banerjee , Mukherjee Priyabrata , Cao Liangxian , Sydorenko Nadiya , Baiazitov Ramil , Moon Young-Choon , Dumble Melissa , Davis Thomas , Bhattacharya Resham
Published: April 2023

Abstract
BMI-1, also known as a stem cell factor, is frequently upregulated in several malignancies. Elevated expression of BMI-1 correlates with poor prognosis and is therefore considered a viable therapeutic target in a number of malignancies including ovarian cancer. Realizing the immense pathologic significance of BMI-1, small-molecule inhibitors against BMI-1 are recently being developed. In this study, we functionally characterize PTC-028, an orally bioavailable compound that decreases BMI-1 levels by posttranslational modification. We report that PTC-028 treatment selectively inhibits cancer cells in clonal growth and viability assays, whereas normal cells remain unaffected. Mechanistically, hyperphosphorylation-mediated depletion of cellular BMI-1 by PTC-028 coupled with a concurrent temporal decrease in ATP and a compromised mitochondrial redox balance potentiates caspase-dependent apoptosis. In vivo, orally administered PTC-028, as a single agent, exhibits significant antitumor activity comparable with the standard cisplatin/paclitaxel therapy in an orthotopic mouse model of ovarian cancer. Thus, PTC-028 has the potential to be used as an effective therapeutic agent in patients with epithelial ovarian cancer, where treatment options are limited. Mol Cancer Ther; 17(1); 39–49. ©2017 AACR.
Data from RAS–MAPK Reactivation Facilitates Acquired Resistance in FGFR1-Amplified Lung Cancer and Underlies a Rationale for Upfront FGFR–MEK Blockade
Authors: Bockorny Bruno , Rusan Maria , Chen Wankun , Liao Rachel G. , Li Yvonne , Piccioni Federica , Wang Jun , Tan Li , Thorner Aaron R. , Li Tianxia , Zhang Yanxi , Miao Changhong , Ovesen Therese , Shapiro Geoffrey I. , Kwiatkowski David J. , Gray Nathanael S. , Meyerson Matthew , Hammerman Peter S. , Bass Adam J.
Published: April 2023

Abstract
The FGFR kinases are promising therapeutic targets in multiple cancer types, including lung and head and neck squamous cell carcinoma, cholangiocarcinoma, and bladder cancer. Although several FGFR kinase inhibitors have entered clinical trials, single-agent clinical efficacy has been modest and resistance invariably occurs. We therefore conducted a genome-wide functional screen to characterize mechanisms of resistance to FGFR inhibition in a FGFR1-dependent lung cancer cellular model. Our screen identified known resistance drivers, such as MET, and additional novel resistance mediators including members of the neurotrophin receptor pathway (NTRK), the TAM family of tyrosine kinases (TYRO3, MERTK, AXL), and MAPK pathway, which were further validated in additional FGFR-dependent models. In an orthogonal approach, we generated a large panel of resistant clones by chronic exposure to FGFR inhibitors in FGFR1- and FGFR3-dependent cellular models and characterized gene expression profiles employing the L1000 platform. Notably, resistant clones had enrichment for NTRK and MAPK signaling pathways. Novel mediators of resistance to FGFR inhibition were found to compensate for FGFR loss in part through reactivation of MAPK pathway. Intriguingly, coinhibition of FGFR and specific receptor tyrosine kinases identified in our screen was not sufficient to suppress ERK activity or to prevent resistance to FGFR inhibition, suggesting a redundant reactivation of RAS–MAPK pathway. Dual blockade of FGFR and MEK, however, proved to be a more powerful approach in preventing resistance across diverse FGFR dependencies and may represent a therapeutic opportunity to achieve durable responses to FGFR inhibition in FGFR-dependent cancers. Mol Cancer Ther; 17(7); 1526–39. ©2018 AACR.
Data from Characterizing the Potency and Impact of Carbon Ion Therapy in a Primary Mouse Model of Soft Tissue Sarcoma
Authors: Brownstein Jeremy M. , Wisdom Amy J. , Castle Katherine D. , Mowery Yvonne M. , Guida Peter , Lee Chang-Lung , Tommasino Francesco , Tessa Chiara La , Scifoni Emanuele , Gao Junheng , Luo Lixia , Campos Lorraine Da Silva , Ma Yan , Williams Nerissa , Jung Sin-Ho , Durante Marco , Kirsch David G.
Published: April 2023

Abstract
Carbon ion therapy (CIT) offers several potential advantages for treating cancers compared with X-ray and proton radiotherapy, including increased biological efficacy and more conformal dosimetry. However, CIT potency has not been characterized in primary tumor animal models. Here, we calculate the relative biological effectiveness (RBE) of carbon ions compared with X-rays in an autochthonous mouse model of soft tissue sarcoma. We used Cre/loxP technology to generate primary sarcomas in KrasLSL-G12D/+; p53fl/fl mice. Primary tumors were irradiated with a single fraction of carbon ions (10 Gy), X-rays (20 Gy, 25 Gy, or 30 Gy), or observed as controls. The RBE was calculated by determining the dose of X-rays that resulted in similar time to posttreatment tumor volume quintupling and exponential growth rate as 10 Gy carbon ions. The median tumor volume quintupling time and exponential growth rate of sarcomas treated with 10 Gy carbon ions and 30 Gy X-rays were similar: 27.3 and 28.1 days and 0.060 and 0.059 mm3/day, respectively. Tumors treated with lower doses of X-rays had faster regrowth. Thus, the RBE of carbon ions in this primary tumor model is 3. When isoeffective treatments of carbon ions and X-rays were compared, we observed significant differences in tumor growth kinetics, proliferative indices, and immune infiltrates. We found that carbon ions were three times as potent as X-rays in this aggressive tumor model and identified unanticipated differences in radiation response that may have clinical implications. Mol Cancer Ther; 17(4); 858–68. ©2018 AACR.
Data from Improving the In Vivo Efficacy of an Anti-Tac (CD25) Immunotoxin by Pseudomonas Exotoxin A Domain II Engineering
Authors: Kaplan Gilad , Mazor Ronit , Lee Fred , Jang Youjin , Leshem Yasmin , Pastan Ira
Published: April 2023

Abstract
Tac (CD25) is expressed on multiple hematologic malignancies and is a target for cancer therapies. LMB-2 is an extremely active anti-Tac recombinant immunotoxin composed of an Fv that binds to Tac and a 38-kDa fragment of Pseudomonas exotoxin A (PE38). Although LMB-2 has shown high cytotoxicity toward Tac-expressing cancer cells in clinical trials, its efficacy was hampered by the formation of anti-drug antibodies against the immunogenic bacterial toxin and by dose-limiting off-target toxicity. To reduce toxin immunogenicity and nonspecific toxicity, we introduced six point mutations into domain III that were previously shown to reduce T-cell immunogenicity and deleted domain II from the toxin, leaving only the 11aa furin cleavage site, which is required for cytotoxic activity. Although this strategy has been successfully implemented for mesothelin and CD22-targeting immunotoxins, we found that removal of domain II significantly lowered the cytotoxic activity of anti-Tac immunotoxins. To restore cytotoxic activity in the absence of PE domain II, we implemented a combined rational design and screening approach to isolate highly active domain II–deleted toxin variants. The domain II–deleted variant with the highest activity contained an engineered disulfide-bridged furin cleavage site designed to mimic its native conformation within domain II. We found that this approach restored 5-fold of the cytotoxic activity and dramatically improved the MTD. Both of these improvements led to significantly increased antitumor efficacy in vivo. We conclude that the next-generation anti-Tac immunotoxin is an improved candidate for targeting Tac-expressing malignancies. Mol Cancer Ther; 17(7); 1486–93. ©2018 AACR.