bluuebunny/crossref_metadata_2025 huggingface dataset:
Data from Cyclophosphamide-Mediated Tumor Priming for Enhanced Delivery and Antitumor Activity of HER2-Targeted Liposomal Doxorubicin (MM-302)
Authors: Geretti Elena , Leonard Shannon Curtis , Dumont Nancy , Lee Helen , Zheng Jinzi , De Souza Raquel , Gaddy Daniel F. , Espelin Christopher W. , Jaffray David A. , Moyo Victor , Nielsen Ulrik B. , Wickham Thomas J. , Hendriks Bart S.
Published: April 2023

Abstract
Given the bulky nature of nanotherapeutics relative to small molecules, it is hypothesized that effective tumor delivery and penetration are critical barriers to their clinical activity. HER2-targeted PEGylated liposomal doxorubicin (MM-302, HER2-tPLD) is an antibody–liposomal drug conjugate designed to deliver doxorubicin to HER2-overexpressing cancer cells while limiting uptake into nontarget cells. In this work, we demonstrate that the administration and appropriate dose sequencing of cyclophosphamide can improve subsequent MM-302 delivery and enhance antitumor activity in preclinical models without negatively affecting nontarget tissues, such as the heart and skin. We demonstrate that this effect is critically dependent on the timing of cyclophosphamide administration. Furthermore, the effect was found to be unique to cyclophosphamide and related analogues, and not shared by other agents, such as taxanes or eribulin, under the conditions examined. Analysis of the cyclophosphamide-treated tumors suggests that the mechanism for improved MM-302 delivery involves the induction of tumor cell apoptosis, reduction of overall tumor cell density, substantial lowering of interstitial fluid pressure, and increasing vascular perfusion. The novel dosing strategy for cyclophosphamide described herein is readily translatable to standard clinical regimens, represents a potentially significant advance in addressing the drug delivery challenge, and may have broad applicability for nanomedicines. This work formed the basis for clinical evaluation of cyclophosphamide for improving liposome deposition as part of an ongoing phase I clinical trial of MM-302 in HER2-positive metastatic breast cancer. Mol Cancer Ther; 14(9); 2060–71. ©2015 AACR.
Data from Sensitization of Glioblastoma Cells to Irradiation by Modulating the Glucose Metabolism
Authors: Shen Han , Hau Eric , Joshi Swapna , Dilda Pierre J. , McDonald Kerrie L.
Published: April 2023

Abstract
Because radiotherapy significantly increases median survival in patients with glioblastoma, the modulation of radiation resistance is of significant interest. High glycolytic states of tumor cells are known to correlate strongly with radioresistance; thus, the concept of metabolic targeting needs to be investigated in combination with radiotherapy. Metabolically, the elevated glycolysis in glioblastoma cells was observed postradiotherapy together with upregulated hypoxia-inducible factor (HIF)-1α and its target pyruvate dehydrogenase kinase 1 (PDK1). Dichloroacetate, a PDK inhibitor currently being used to treat lactic acidosis, can modify tumor metabolism by activating mitochondrial activity to force glycolytic tumor cells into oxidative phosphorylation. Dichloroacetate alone demonstrated modest antitumor effects in both in vitro and in vivo models of glioblastoma and has the ability to reverse the radiotherapy-induced glycolytic shift when given in combination. In vitro, an enhanced inhibition of clonogenicity of a panel of glioblastoma cells was observed when dichloroacetate was combined with radiotherapy. Further mechanistic investigation revealed that dichloroacetate sensitized glioblastoma cells to radiotherapy by inducing the cell-cycle arrest at the G2–M phase, reducing mitochondrial reserve capacity, and increasing the oxidative stress as well as DNA damage in glioblastoma cells together with radiotherapy. In vivo, the combinatorial treatment of dichloroacetate and radiotherapy improved the survival of orthotopic glioblastoma-bearing mice. In conclusion, this study provides the proof of concept that dichloroacetate can effectively sensitize glioblastoma cells to radiotherapy by modulating the metabolic state of tumor cells. These findings warrant further evaluation of the combination of dichloroacetate and radiotherapy in clinical trials. Mol Cancer Ther; 14(8); 1794–804. ©2015 AACR.
Data from Neuregulin Signaling Is a Mechanism of Therapeutic Resistance in Head and Neck Squamous Cell Carcinoma
Authors: Baro Marta , Lopez Sambrooks Cecilia , Burtness Barbara A. , Lemmon Mark A. , Contessa Joseph N.
Published: April 2023

Abstract
EGFR signaling confers resistance to radiotherapy and is a validated target in head and neck squamous cell carcinoma (HNSCC). The inhibition of EGFR in combination with radiotherapy improves local control and overall survival in these patients; however, therapeutic resistance limits the efficacy of this approach. We therefore sought to identify cellular mechanisms that cause resistance to EGFR inhibition and radiotherapy in HNSCC. Though clonal isolation of carcinoma cells exposed to increasing concentrations of cetuximab, we found that resistant cells upregulate prosurvival ErbB3 and AKT signaling. Using EFM-19 cells and confirmatory analysis of protein levels, we demonstrate that cetuximab resistance is characterized by enhanced neuregulin expression identifying a novel adaptive mechanism of therapeutic resistance. Inhibition of this autocrine loop with CDX-3379 (an ErbB3 specific antibody) was sufficient to block ErbB3/AKT signaling in cetuximab resistant cells. The combination of CDX-3379 and cetuximab reduced proliferation and survival after radiotherapy in several HNSCC cell lines. These in vitro findings were confirmed in xenograft tumor growth experiments including an approach using growth factor–supplemented Matrigel. In vivo, the delivery of EGFR and ErbB3 antibodies significantly reduced tumor growth in cetuximab-resistant FaDu and CAL27 xenografts. In summary, this work demonstrates that autocrine NRG ligand secretion is a mechanism for therapeutic resistance to cetuximab and radiotherapy. This cross-resistance to both therapeutic modalities identifies NRG as an actionable therapeutic target for improving treatment regimens in HNSCC.
Data from Monoclonal Antibody Targeting Sialyl-di-Lewisa–Containing Internalizing and Noninternalizing Glycoproteins with Cancer Immunotherapy Development Potential
Authors: Tivadar Silvana T. , McIntosh Richard S. , Chua Jia Xin , Moss Robert , Parsons Tina , Zaitoun Abed M. , Madhusudan Srinivasan , Durrant Lindy G. , Vankemmelbeke Mireille
Published: April 2023

Abstract
Tumor glycans constitute attractive targets for therapeutic antibodies. The sialylated glycocalyx plays a prominent role in cancer progression and immune evasion. Here, we describe the characterization of the mAb, FG129, which targets tumor-associated sialylated glycan, and demonstrate its potential for multimodal cancer therapy. FG129, obtained through BALB/c mouse immunizations with liposomes containing membrane glycan extracts from the colorectal cancer cell line LS180, is an mIgG1κ that targets sialyl-di-Lewisa–containing glycoproteins. FG129, as well as its chimeric human IgG1 variant, CH129, binds with nanomolar functional affinity to a range of colorectal, pancreatic, and gastric cancer cell lines. FG129 targets 74% (135/182) of pancreatic, 50% (46/92) of gastric, 36% (100/281) of colorectal, 27% (89/327) of ovarian, and 21% (42/201) of non–small cell lung cancers, by IHC. In our pancreatic cancer cohort, high FG129 glyco-epitope expression was significantly associated with poor prognosis (P = 0.004). Crucially, the glyco-epitope displays limited normal tissue distribution, with FG129 binding weakly to a small percentage of cells within gallbladder, ileum, liver, esophagus, pancreas, and thyroid tissues. Owing to glyco-epitope internalization, we validated payload delivery by CH129 through monomethyl auristatin E (MMAE) or maytansinoid (DM1 and DM4) conjugation. All three CH129 drug conjugates killed high-binding colorectal and pancreatic cancer cell lines with (sub)nanomolar potency, coinciding with significant in vivo xenograft tumor control by CH129-vcMMAE. CH129, with its restricted normal tissue distribution, avid tumor binding, and efficient payload delivery, is a promising candidate for the treatment of sialyl-di-Lewisa–expressing solid tumors, as an antibody–drug conjugate or as an alternative cancer immunotherapy modality.
Data from A Multifunctional Therapy Approach for Cancer: Targeting Raf1- Mediated Inhibition of Cell Motility, Growth, and Interaction with the Microenvironment
Authors: Zhang Limin , Pattanayak Abhinandan , Li Wenqi , Ko Hyun-Kyung , Fowler Graham , Gordon Ryan , Bergan Raymond
Published: April 2023

Abstract
Prostate cancer cells move from their primary site of origin, interact with a distant microenvironment, grow, and thereby cause death. It had heretofore not been possible to selectively inhibit cancer cell motility. Our group has recently shown that inhibition of intracellular activation of Raf1 with the small-molecule therapeutic KBU2046 permits, for the first time, selective inhibition of cell motility. We hypothesized that simultaneous disruption of multiple distinct functions that drive progression of prostate cancer to induce death would result in advanced disease control. Using a murine orthotopic implantation model of human prostate cancer metastasis, we demonstrate that combined treatment with KBU2046 and docetaxel retains docetaxel's antitumor action, but provides improved inhibition of metastasis, compared with monotherapy. KBU2046 does not interfere with hormone therapy, inclusive of enzalutamide-mediated inhibition of androgen receptor (AR) function and cell growth inhibition, and inclusive of the ability of castration to inhibit LNCaP-AR cell outgrowth in mice. Cell movement is necessary for osteoclast-mediated bone degradation. KBU2046 inhibits Raf1 and its downstream activation of MEK1/2 and ERK1/2 in osteoclasts, inhibiting cytoskeleton rearrangement, resorptive cavity formation, and bone destruction in vitro, with improved effects observed when the bone microenvironment is chemically modified by pretreatment with zoledronic acid. Using a murine cardiac injection model of human prostate cancer bone destruction quantified by CT, KBU2046 plus zoledronic exhibit improved inhibitory efficacy, compared with monotherapy. The combined disruption of pathways that drive cell movement, interaction with bone, and growth constitutes a multifunctional targeting strategy that provides advanced disease control.
Data from MEN1309/OBT076, a First-In-Class Antibody–Drug Conjugate Targeting CD205 in Solid Tumors
Authors: Merlino Giuseppe , Fiascarelli Alessio , Bigioni Mario , Bressan Alessandro , Carrisi Corrado , Bellarosa Daniela , Salerno Massimiliano , Bugianesi Rossana , Manno Rosanna , Bernadó Morales Cristina , Arribas Joaquin , Bisht Arnima , Kaplan Angelo , Boyd Robert , Do Uyen T. , Swaminathan Sudha , Attanasio Nickolas , Lou San Lin , Dusek Rachel L. , Ackroyd James E. , Pham Phuoc Huy , Awdew Rahel , Aud Dee , Trang Michael , Lynch Carmel M. , Terrett Jonathan , Wilson Keith E. , Rohlff Christian , Manzini Stefano , Pellacani Andrea , Binaschi Monica
Published: April 2023

Abstract
CD205 is a type I transmembrane glycoprotein and is a member of the C-type lectin receptor family. Analysis by mass spectrometry revealed that CD205 was robustly expressed and highly prevalent in a variety of solid malignancies from different histotypes. IHC confirmed the increased expression of CD205 in pancreatic, bladder, and triple-negative breast cancer (TNBC) compared with that in the corresponding normal tissues. Using immunofluorescence microscopy, rapid internalization of the CD205 antigen was observed. These results supported the development of MEN1309/OBT076, a fully humanized CD205-targeting mAb conjugated to DM4, a potent maytansinoid derivate, via a cleavable N-succinimidyl-4-(2-pyridyldithio) butanoate linker. MEN1309/OBT076 was characterized in vitro for target binding affinity, mechanism of action, and cytotoxic activity against a panel of cancer cell lines. MEN1309/OBT076 displayed selective and potent cytotoxic effects against tumor cells exhibiting strong and low to moderate CD205 expression. In vivo, MEN1309/OBT076 showed potent antitumor activity resulting in durable responses and complete tumor regressions in many TNBC, pancreatic, and bladder cancer cell line–derived and patient-derived xenograft models, independent of antigen expression levels. Finally, the pharmacokinetics and pharmacodynamic profile of MEN1309/OBT076 was characterized in pancreatic tumor–bearing mice, demonstrating that the serum level of antibody–drug conjugate (ADC) achieved through dosing was consistent with the kinetics of its antitumor activity. Overall, our data demonstrate that MEN1309/OBT076 is a novel and selective ADC with potent activity against CD205-positive tumors. These data supported the clinical development of MEN1309/OBT076, and further evaluation of this ADC is currently ongoing in the first-in-human SHUTTLE clinical trial.
Data from Preclinical Development of the Anti-LAG-3 Antibody REGN3767: Characterization and Activity in Combination with the Anti-PD-1 Antibody Cemiplimab in Human PD-1xLAG-3–Knockin Mice
Authors: Burova Elena , Hermann Aynur , Dai Jie , Ullman Erica , Halasz Gabor , Potocky Terra , Hong Seongwon , Liu Matt , Allbritton Omaira , Woodruff Amy , Pei Jerry , Rafique Ashique , Poueymirou William , Martin Joel , MacDonald Douglas , Olson William C. , Murphy Andrew , Ioffe Ella , Thurston Gavin , Mohrs Markus
Published: April 2023

Abstract
In the tumor microenvironment, multiple inhibitory checkpoint receptors can suppress T-cell function, thereby enabling tumor immune evasion. Blockade of one of these checkpoint receptors, PD-1, with therapeutic antibodies has produced positive clinical responses in various cancers; however, the efficacy of this approach can be further improved. Simultaneously targeting multiple inhibitory checkpoint receptors has emerged as a promising therapeutic strategy. Here, we report the development and characterization of REGN3767, a fully human IgG4 antibody targeting LAG-3, another inhibitory receptor on T cells. REGN3767 binds human and monkey LAG-3 with high affinity and specificity and blocks the interaction of LAG-3 with its ligand, MHC class II. In an engineered T-cell/antigen-presenting cell bioassay, REGN3767 alone, or in combination with cemiplimab (REGN2810, human anti-PD-1 antibody), blocked inhibitory signaling to T cells mediated by hLAG-3/MHCII in the presence of PD-1/PD-L1. To test the in vivo activity of REGN3767 alone or in combination with cemiplimab, we generated human PD-1xLAG-3 knockin mice, in which the extracellular domains of mouse Pdcd1 and Lag3 were replaced with their human counterparts. In these humanized mice, treatment with cemiplimab and REGN3767 showed increased efficacy in a mouse tumor model and enhanced the secretion of proinflammatory cytokines by tumor-specific T cells. The favorable pharmacokinetics and toxicology of REGN3767 in nonhuman primates, together with enhancement of antitumor efficacy of anti-PD-1 antibody in preclinical tumor models, support its clinical development.
Data from TAS0728, A Covalent-binding, HER2-selective Kinase Inhibitor Shows Potent Antitumor Activity in Preclinical Models
Authors: Irie Hiroki , Ito Kimihiro , Fujioka Yayoi , Oguchi Kei , Fujioka Akio , Hashimoto Akihiro , Ohsawa Hirokazu , Tanaka Kenji , Funabashi Kaoru , Araki Hikari , Kawai Yuichi , Shimamura Tadashi , Wadhwa Renu , Ohkubo Shuichi , Matsuo Kenichi
Published: April 2023

Abstract
Activated HER2 is a promising therapeutic target for various cancers. Although several reports have described HER2 inhibitors in development, no covalent-binding inhibitor selective for HER2 has been reported. Here, we report a novel compound TAS0728 that covalently binds to HER2 at C805 and selectively inhibits its kinase activity. Once TAS0728 bound to HER2 kinase, the inhibitory activity was not affected by a high ATP concentration. A kinome-wide biochemical panel and cellular assays established that TAS0728 possesses high specificity for HER2 over wild-type EGFR. Cellular pharmacodynamics assays using MCF10A cells engineered to express various mutated HER2 genes revealed that TAS0728 potently inhibited the phosphorylation of mutated HER2 and wild-type HER2. Furthermore, TAS0728 exhibited robust and sustained inhibition of the phosphorylation of HER2, HER3, and downstream effectors, thereby inducing apoptosis of HER2-amplified breast cancer cells and in tumor tissues of a xenograft model. TAS0728 induced tumor regression in mouse xenograft models bearing HER2 signal–dependent tumors and exhibited a survival benefit without any evident toxicity in a peritoneal dissemination mouse model bearing HER2-driven cancer cells. Taken together, our results demonstrated that TAS0728 may offer a promising therapeutic option with improved efficacy as compared with current HER2 inhibitors for HER2-activated cancers. Assessment of TAS0728 in ongoing clinical trials is awaited (NCT03410927).
Data from Dipyridamole Enhances the Cytotoxicities of Trametinib against Colon Cancer Cells through Combined Targeting of HMGCS1 and MEK Pathway
Authors: Zhou Sheng , Xu Huanji , Tang Qiulin , Xia Hongwei , Bi Feng
Published: April 2023

Abstract
Both the MAPK pathway and mevalonate (MVA) signaling pathway play an increasingly significant role in the carcinogenesis of colorectal carcinoma, whereas the cross-talk between these two pathways and its implication in targeted therapy remains unclear in colorectal carcinoma. Here, we identified that HMGCS1 (3-hydroxy-3-methylglutaryl-CoA synthase 1), the rate-limiting enzyme of the MVA pathway, is overexpressed in colon cancer tissues and positively regulates the cell proliferation, migration, and invasion of colon cancer cells. In addition, HMGCS1 could enhance the activity of pERK independent of the MVA pathway, and the suppression of HMGCS1 could completely reduce the EGF-induced proliferation of colon cancer cells. Furthermore, we found that trametinib, a MEK inhibitor, could only partially abolish the upregulation of HMGCS1 induced by EGF treatment, while combination with HMGCS1 knockdown could completely reverse the upregulation of HMGCS1 induced by EGF treatment and increase the sensitivity of colon cancer cells to trametinib. Finally, we combined trametinib and dipyridamole, a common clinically used drug that could suppress the activity of SREBF2 (sterol regulatory element-binding transcription factor 2), a transcription factor regulating HMGCS1 expression, and identified its synergistic effect in inhibiting the proliferation and survival of colon cancer cells in vitro as well as the in vivo tumorigenic potential of colon cancer cells. Together, the current data indicated that HMGCS1 may be a novel biomarker, and the combination of targeting HMGCS1 and MEK might be a promising therapeutic strategy for patients with colon cancer.
Data from Dual HER2/PIK3CA Targeting Overcomes Single-Agent Acquired Resistance in HER2-Amplified Uterine Serous Carcinoma Cell Lines In Vitro and In Vivo
Authors: Lopez Salvatore , Cocco Emiliano , Black Jonathan , Bellone Stefania , Bonazzoli Elena , Predolini Federica , Ferrari Francesca , Schwab Carlton L. , English Diana P. , Ratner Elena , Silasi Dan-Arin , Azodi Masoud , Schwartz Peter E. , Terranova Corrado , Angioli Roberto , Santin Alessandro D.
Published: April 2023

Abstract
HER2/neu gene amplification and PIK3CA driver mutations are common in uterine serous carcinoma (USC) and may represent ideal therapeutic targets against this aggressive variant of endometrial cancer. We examined the sensitivity to neratinib, taselisib, and the combination of the two compounds in in vitro and in vivo experiments using PIK3CA-mutated and PIK3CA wild-type HER2/neu–amplified USC cell lines. Cell viability and cell-cycle distribution were assessed using flow-cytometry assays. Downstream signaling was assessed by immunoblotting. Preclinical efficacy of single versus dual inhibition was evaluated in vivo using two USC xenografts. We found both single-agent neratinib and taselisib to be active but only transiently effective in controlling the in vivo growth of USC xenografts harboring HER2/neu gene amplification with or without oncogenic PIK3CA mutations. In contrast, the combination of the two inhibitors caused a stronger and long-lasting growth inhibition in both USC xenografts when compared with single-agent therapy. Combined targeting of HER2 and PIK3CA was associated with a significant and dose-dependent increase in the percentage of cells in the G0–G1 phase of the cell cycle and a dose-dependent decline in the phosphorylation of S6. Importantly, dual inhibition therapy initiated after tumor progression in single-agent–treated mice was still remarkably effective at inducing tumor regression in both large PIK3CA and pan-ErbB inhibitor–resistant USC xenografts. Dual HER2/PIK3CA blockade may represent a novel therapeutic option for USC patients harboring tumors with HER2/neu gene amplification and mutated or wild-type PIK3CA resistant to chemotherapy. Mol Cancer Ther; 14(11); 2519–26. ©2015 AACR.
Data from Maternal Embryonic Leucine Zipper Kinase (MELK), a Potential Therapeutic Target for Neuroblastoma
Authors: Chlenski Alexandre , Park Chanyoung , Dobratic Marija , Salwen Helen R. , Budke Brian , Park Jae-Hyun , Miller Ryan , Applebaum Mark A. , Wilkinson Emma , Nakamura Yusuke , Connell Philip P. , Cohn Susan L.
Published: April 2023

Abstract
Maternal embryonic leucine zipper kinase (MELK) activates pathways that mediate aggressive tumor growth and therapy resistance in many types of adult cancers. Pharmacologic and genomic inhibition of MELK impairs tumor growth and increases sensitivity to radiation and chemotherapy. On the basis of these promising preclinical studies, early-phase adult clinical trials testing the MELK inhibitor OTS167 are ongoing. To investigate whether MELK is also a therapeutic target in neuroblastoma, we analyzed MELK expression in primary tumors and cell lines, and examined the effects of OTS167 on neuroblastoma growth. In primary tumors, high levels of MELK were associated with advanced stage disease and inferior survival. Higher levels of MELK were also detected in tumorigenic versus nontumorigenic neuroblastoma cell lines, and cells with higher levels of MELK expression were more sensitive to OTS167 than low-MELK expressing cells. OTS167 suppressed the growth of neuroblastoma xenografts, and in a preclinical model of minimal residual disease, survival was prolonged with MELK inhibition. OTS167 treatment downregulated MELK and its target enhancer of zeste homolog 2 (EZH2), a component of the polycomb repressive complex 2 (PRC2) that is known to modulate the DNA damage response. We also show that OTS167 reduced the formation of collapsed replication forks induced by camptothecin or radiation. Taken together, our results indicate that MELK indirectly mediates efficient processing of replication-associated DNA lesions in neuroblastoma, and that OTS167 sensitizes cells to DNA-damaging agents by abrogating this process. Further studies evaluating the activity of combination treatment regimens with OTS167 in neuroblastoma are warranted.
Data from Targeting AXL and the DNA Damage Response Pathway as a Novel Therapeutic Strategy in Melanoma
Authors: Flem-Karlsen Karine , McFadden Erin , Omar Nasrin , Haugen Mads H. , Øy Geir Frode , Ryder Truls , Gullestad Hans Petter , Hermann Robert , Mælandsmo Gunhild Mari , Flørenes Vivi Ann
Published: April 2023

Abstract
Receptor tyrosine kinase AXL is found upregulated in various types of cancer, including melanoma, and correlates with an aggressive cancer phenotype, inducing cell proliferation and epithelial-to-mesenchymal transition. In addition, AXL has recently been linked to chemotherapy resistance, and inhibition of AXL is found to increase DNA damage and reduce expression of DNA repair proteins. In light of this, we aimed to investigate whether targeting AXL together with DNA damage response proteins would be therapeutically beneficial. Using melanoma cell lines, we observed that combined reduction of AXL and CHK1/CHK2 signaling decreased proliferation, deregulated cell-cycle progression, increased apoptosis, and reduced expression of DNA damage response proteins. Enhanced therapeutic effect of combined treatment, as compared with mono-treatment, was further observed in a patient-derived xenograft model and, of particular interest, when applying a three-dimensional ex vivo spheroid drug sensitivity assay on tumor cells harvested directly from 27 patients with melanoma lymph node metastases. Together, these results indicate that targeting AXL together with the DNA damage response pathway could be a promising treatment strategy in melanoma, and that further investigations in patient groups lacking treatment alternatives should be pursued.
Data from The FOXM1 Inhibitor RCM-1 Decreases Carcinogenesis and Nuclear β-Catenin
Authors: Shukla Samriddhi , Milewski David , Pradhan Arun , Rama Nihar , Rice Kathryn , Le Tien , Flick Matthew J. , Vaz Sara , Zhao Xueheng , Setchell Kenneth D. , Logarinho Elsa , Kalinichenko Vladimir V. , Kalin Tanya V.
Published: April 2023

Abstract
The oncogenic transcription factor FOXM1 has been previously shown to play a critical role in carcinogenesis by inducing cellular proliferation in multiple cancer types. A small-molecule compound, Robert Costa Memorial drug-1 (RCM-1), has been recently identified from high-throughput screen as an inhibitor of FOXM1 in vitro and in mouse model of allergen-mediated lung inflammation. In the present study, we examined antitumor activities of RCM-1 using tumor models. Treatment with RCM-1 inhibited tumor cell proliferation as evidenced by increased cell-cycle duration. Confocal imaging of RCM-1–treated tumor cells indicated that delay in cellular proliferation was concordant with inhibition of FOXM1 nuclear localization in these cells. RCM-1 reduced the formation and growth of tumor cell colonies in the colony formation assay. In animal models, RCM-1 treatment inhibited growth of mouse rhabdomyosarcoma Rd76-9, melanoma B16-F10, and human H2122 lung adenocarcinoma. RCM-1 decreased FOXM1 protein in the tumors, reduced tumor cell proliferation, and increased tumor cell apoptosis. RCM-1 decreased protein levels and nuclear localization of β-catenin, and inhibited protein–protein interaction between β-catenin and FOXM1 in cultured tumor cells and in vivo. Altogether, our study provides important evidence of antitumor potential of the small-molecule compound RCM-1, suggesting that RCM-1 can be a promising candidate for anticancer therapy.
Data from The Novel ATR Inhibitor BAY 1895344 Is Efficacious as Monotherapy and Combined with DNA Damage–Inducing or Repair–Compromising Therapies in Preclinical Cancer Models
Authors: Wengner Antje M. , Siemeister Gerhard , Lücking Ulrich , Lefranc Julien , Wortmann Lars , Lienau Philip , Bader Benjamin , Bömer Ulf , Moosmayer Dieter , Eberspächer Uwe , Golfier Sven , Schatz Christoph A. , Baumgart Simon J. , Haendler Bernard , Lejeune Pascale , Schlicker Andreas , von Nussbaum Franz , Brands Michael , Ziegelbauer Karl , Mumberg Dominik
Published: April 2023

Abstract
The DNA damage response (DDR) secures the integrity of the genome of eukaryotic cells. DDR deficiencies can promote tumorigenesis but concurrently may increase dependence on alternative repair pathways. The ataxia telangiectasia and Rad3-related (ATR) kinase plays a central role in the DDR by activating essential signaling pathways of DNA damage repair. Here, we studied the effect of the novel selective ATR kinase inhibitor BAY 1895344 on tumor cell growth and viability. Potent antiproliferative activity was demonstrated in a broad spectrum of human tumor cell lines. BAY 1895344 exhibited strong monotherapy efficacy in cancer xenograft models that carry DNA damage repair deficiencies. The combination of BAY 1895344 with DNA damage–inducing chemotherapy or external beam radiotherapy (EBRT) showed synergistic antitumor activity. Combination treatment with BAY 1895344 and DDR inhibitors achieved strong synergistic antiproliferative activity in vitro, and combined inhibition of ATR and PARP signaling using olaparib demonstrated synergistic antitumor activity in vivo. Furthermore, the combination of BAY 1895344 with the novel, nonsteroidal androgen receptor antagonist darolutamide resulted in significantly improved antitumor efficacy compared with respective single-agent treatments in hormone-dependent prostate cancer, and addition of EBRT resulted in even further enhanced antitumor efficacy. Thus, the ATR inhibitor BAY 1895344 may provide new therapeutic options for the treatment of cancers with certain DDR deficiencies in monotherapy and in combination with DNA damage–inducing or DNA repair–compromising cancer therapies by improving their efficacy.
Data from Identifying Candidate Druggable Targets in Canine Cancer Cell Lines Using Whole-Exome Sequencing
Authors: Das Sunetra , Idate Rupa , Cronise Kathryn E. , Gustafson Daniel L. , Duval Dawn L.
Published: April 2023

Abstract
Cancer cell culture has been a backbone in cancer research, in which analysis of human cell line mutational profiles often correlates with oncogene addiction and drug sensitivity. We have conducted whole-exome sequence analyses on 33 canine cancer cell lines from 10 cancer types to identify somatic variants that contribute to pathogenesis and therapeutic sensitivity. A total of 66,344 somatic variants were identified. Mutational load ranged from 15.79 to 129.37 per Mb, and 13.2% of variants were located in protein-coding regions (PCR) of 5,085 genes. PCR somatic variants were identified in 232 genes listed in the Cancer Gene Census (COSMIC). Cross-referencing variants with human driving mutations on cBioPortal identified 61 variants as candidate cancer drivers in 30 cell lines. The most frequently mutated cancer driver was TP53 (15 mutations in 12 cell lines). No drivers were identified in three cell lines. We identified 501 non-COSMIC genes with PCR variants that functionally annotate with COSMIC genes. These genes frequently mapped to the KEGG MAPK and PI3K–AKT pathways. We evaluated the cell lines for ERK1/2 and AKT(S473) phosphorylation and sensitivity to the MEK1/2 inhibitor, trametinib. Twelve of the 33 cell lines were trametinib-sensitive (IC50 < 32 nmol/L), all 12 exhibited constitutive or serum-activated ERK1/2 phosphorylation, and 8 carried MAPK pathway cancer driver variants: NF1(2), BRAF(3), N/KRAS(3). This functionally annotated database of canine cell line variants will inform hypothesis-driven preclinical research to support the use of companion animals in clinical trials to test novel combination therapies.
Data from Blood Interactions, Pharmacokinetics, and Depth-Dependent Ablation of Rat Mammary Tumors with Photoactivatable, Liposomal Doxorubicin
Authors: Carter Kevin A. , Luo Dandan , Geng Jumin , Stern Stephan T. , Lovell Jonathan F.
Published: April 2023

Abstract
Photosensitizers can be integrated with drug delivery vehicles to develop chemophototherapy agents with antitumor synergy between chemo- and photocomponents. Long-circulating doxorubicin (Dox) in porphyrin–phospholipid (PoP) liposomes (LC-Dox-PoP) incorporates a phospholipid-like photosensitizer (2 mole %) in the bilayer of Dox-loaded stealth liposomes. Hematological effects of endotoxin-minimized LC-Dox-PoP were characterized via standardized assays. In vitro interaction with erythrocytes, platelets, and plasma coagulation cascade were generally unremarkable, whereas complement activation was found to be similar to that of commercial Doxil. Blood partitioning suggested that both the Dox and PoP components of LC-Dox-PoP were stably entrapped or incorporated in liposomes. This was further confirmed with pharmacokinetic studies in Fischer rats, which showed the PoP and Dox components of the liposomes both had nearly identical, long circulation half-lives (25–26 hours). In a large orthotopic mammary tumor model in Fischer rats, following intravenous dosing (2 mg/kg Dox), the depth of enhanced Dox delivery in response to 665 nm laser irradiation was over 1 cm. LC-Dox-PoP with laser treatment cured or potently suppressed tumor growth, with greater efficacy observed in tumors 0.8 to 1.2 cm, compared with larger ones. The skin at the treatment site healed within approximately 30 days. Taken together, these data provide insight into nanocharacterization and photo-ablation parameters for a chemophototherapy agent.
Data from Prognostic and Biologic Relevance of Clinically Applicable Long Noncoding RNA Profiling in Older Patients with Cytogenetically Normal Acute Myeloid Leukemia
Authors: Papaioannou Dimitrios , Nicolet Deedra , Ozer Hatice G. , Mrózek Krzysztof , Volinia Stefano , Fadda Paolo , Carroll Andrew J. , Kohlschmidt Jessica , Kolitz Jonathan E. , Wang Eunice S. , Stone Richard M. , Byrd John C. , Garzon Ramiro , Bloomfield Clara D.
Published: April 2023

Abstract
We have previously shown that expression levels of 48 long noncoding RNAs (lncRNA) can generate a prognostic lncRNA score that independently associates with outcome of older patients with cytogenetically normal acute myeloid leukemia (CN-AML). However, the techniques used to identify and measure prognostic lncRNAs (i.e., RNA sequencing and microarrays) are not tailored for clinical testing. Herein, we report on an assay (based on the nCounter platform) that is designed to produce targeted measurements of prognostic lncRNAs in a clinically applicable manner. We analyzed a new cohort of 76 older patients with CN-AML and found that the nCounter assay yielded reproducible measurements and that the lncRNA score retained its prognostic value; patients with high lncRNA scores had lower complete remission (CR) rates (P = 0.009; 58% vs. 87%), shorter disease-free (P = 0.05; 3-year rates: 0% vs. 21%), overall (OS; P = 0.02, 3-year rates: 10% vs. 29%), and event-free survival (EFS; P = 0.002, 3-year rates: 0% vs. 18%) than patients with low lncRNA scores. In multivariable analyses, the lncRNA score independently associated with CR rates (P = 0.02), OS (P = 0.02), and EFS (P = 0.02). To gain biological insights, we examined our initial cohort of 71 older patients with CN-AML, previously analyzed with RNA sequencing. Genes involved in immune response and B-cell receptor signaling were enriched in patients with high lncRNA scores. We conclude that clinically applicable lncRNA profiling is feasible and potentially useful for risk stratification of older patients with CN-AML. Furthermore, we identify potentially targetable molecular pathways that are active in the high-risk patients with high lncRNA scores.
Data from Targeting of BRM Sensitizes BRG1-Mutant Lung Cancer Cell Lines to Radiotherapy
Authors: Zernickel Erika , Sak Ali , Riaz Assad , Klein Diana , Groneberg Michael , Stuschke Martin
Published: April 2023

Abstract
Targeting of epigenetic regulators as the chromatin remodeler SWI/SNF is proving to be a promising therapeutic strategy for individualized treatment of cancer patients. Here, we tested whether targeting one of the two mutually exclusive subdomains of the SWI/SNF complex BRM/SMARCA2 can sensitize specifically non–small cell lung carcinoma (NSCLC) cells with mutations in the other subunit BRG1/SMARCA4 toward ionizing radiation (IR). Knockdown of BRM with siRNA or shRNA and its consequences for radiation sensitivity as measured by clonogenic survival and plaque-monolayer control was studied in different NSCLC lines with or without BRG1 mutations and in primary fibroblasts. Furthermore, the effect on double-strand break (DSB) repair markers measured by immunofluorescence staining of 53BP1-, γ-H2AX-, and Rad51-foci was investigated. BRG1-mutated cell lines showed an increased surviving fraction compared with BRG1 proficient cells. Depletion of BRM (i) leads to a decreased proliferation rate and plating efficiency specifically in BRG1-mutated cells, (ii) specifically sensitized BRG1-mutant NSCLC cells toward IR as characterized by a survival reducing factor of 0.63 [95% confidence interval (CI), 0.57–0.69] in the dose range between 2 and 6 Gy, and (iii) decreased the tumor control doses after daily fractionation at 4 Gy in BRG1-mutant NSCLC cell lines A549 and H1299 in minimonolayers by 9.9% ± 1.3% and 13.6% ± 1.8%, respectively. In addition, an increase of residual Rad51-foci at 24 hours after irradiation in BRG1-mutant cells was demonstrated. Therefore, targeting of BRM in combination with radiotherapy is supposed to improve the therapeutic outcome of lung cancer patients harboring BRG1 mutations.

The present study shows that the moderate radioresponsiveness of NSCLC cells with BRG1 mutations can be increased upon BRM depletion that is associated with a prolonged Rad51-foci prevalence at DNA DSBs.
Data from Mutant-Selective Irreversible EGFR Inhibitor, Naquotinib, Inhibits Tumor Growth in NSCLC Models with EGFR-Activating Mutations, T790M Mutation, and AXL Overexpression
Authors: Tanaka Hiroaki , Sakagami Hideki , Kaneko Naoki , Konagai Satoshi , Yamamoto Hiroko , Matsuya Takahiro , Yuri Masatoshi , Yamanaka Yosuke , Mori Masamichi , Takeuchi Masahiro , Koshio Hiroyuki , Hirano Masaaki , Kuromitsu Sadao
Published: April 2023

Abstract
First- and second-generation EGFR tyrosine kinase inhibitors (TKI) are effective clinical therapies for patients with non–small cell lung cancer (NSCLC) harboring EGFR-activating mutations. However, almost all patients develop resistance to these drugs. The EGFR T790M mutation of EGFR is the most predominant mechanism for resistance. In addition, activation of AXL signaling is one of the suggested alternative bypassing pathways for resistance to EGFR-TKIs. Here, we report that naquotinib, a pyrazine carboxamide–based EGFR-TKI, inhibited EGFR with activating mutations, as well as T790M resistance mutation while sparing wild-type (WT) EGFR. In in vivo murine xenograft models using cell lines and a patient-derived xenograft model, naquotinib induced tumor regression of NSCLC with EGFR-activating mutations with or without T790M resistance mutation, whereas it did not significantly inhibit WT EGFR signaling in skin. Furthermore, naquotinib suppressed tumor recurrence during the treatment period of 90 days. In addition, unlike erlotinib and osimertinib, naquotinib inhibited the phosphorylation of AXL and showed antitumor activity against PC-9 cells overexpressing AXL in vitro and in vivo. Our findings suggest that naquotinib has therapeutic potential in patients with NSCLC with EGFR-activating mutations, T790M resistance mutation, and AXL overexpression.
Data from Antiproliferative Effects of Monoclonal Antibodies against (Pro)Renin Receptor in Pancreatic Ductal Adenocarcinoma
Authors: Rahman Asadur , Matsuyama Makoto , Ebihara Akio , Shibayama Yuki , Hasan Arif Ul , Nakagami Hironori , Suzuki Fumiaki , Sun Jiao , Kobayashi Tomoe , Hayashi Hiroki , Nakano Daisuke , Kobara Hideki , Masaki Tsutomu , Nishiyama Akira
Published: April 2023

Abstract
We previously reported that silencing of the PRR gene, which encodes the (pro)renin receptor [(P)RR], significantly reduced Wnt/β-catenin–dependent development of pancreatic ductal adenocarcinoma (PDAC). Here, we examined the effects of a panel of blocking mAbs directed against the (P)RR extracellular domain on proliferation of the human PDAC cell lines PK-1 and PANC-1 in vitro and in vivo. We observed that four rat anti-(P)RR mAbs induced accumulation of cells in the G0–G1-phase of the cell cycle and significantly reduced proliferation in vitro concomitant with an attenuation of Wnt/β-catenin signaling. Systemic administration of the anti-(P)RR mAbs to nude mice bearing subcutaneous PK-1 xenografts significantly decreased tumor expression of active β-catenin and the proliferation marker Ki-67, and reduced tumor growth. In contrast, treatment with the handle region peptide of (pro)renin did not inhibit tumor growth in vitro or in vivo, indicating that the effects of the anti-(P)RR mAbs were independent of the renin–angiotensin system. These data indicate that mAbs against human (P)RR can suppress PDAC cell proliferation by hindering activation of the Wnt/β-catenin signaling pathway. Thus, mAb-mediated (P)RR blockade could be an attractive therapeutic strategy for PDAC.
Data from Upregulation of AKT3 Confers Resistance to the AKT Inhibitor MK2206 in Breast Cancer
Authors: Stottrup Casey , Tsang Tiffany , Chin Y. Rebecca
Published: April 2023

Abstract
Acquired resistance to molecular targeted therapy represents a major challenge for the effective treatment of cancer. Hyperactivation of the PI3K/AKT pathway is frequently observed in virtually all human malignancies, and numerous PI3K and AKT inhibitors are currently under clinical evaluation. However, mechanisms of acquired resistance to AKT inhibitors have yet to be described. Here, we use a breast cancer preclinical model to identify resistance mechanisms to a small molecule allosteric AKT inhibitor, MK2206. Using a step-wise and chronic high-dose exposure, breast cancer cell lines harboring oncogenic PI3K resistant to MK2206 were established. Using this model, we reveal that AKT3 expression is markedly upregulated in AKT inhibitor–resistant cells. Induction of AKT3 is regulated epigenetically by the bromodomain and extra terminal domain proteins. Importantly, knockdown of AKT3, but not AKT1 or AKT2, in resistant cells restores sensitivity to MK2206. AKT inhibitor–resistant cells also display an epithelial to mesenchymal transition phenotype as assessed by alterations in the levels of E-Cadherin, N-Cadherin, and vimentin, as well as enhanced invasiveness of tumor spheroids. Notably, the invasive morphology of resistant spheroids is diminished upon AKT3 depletion. We also show that resistance to MK2206 is reversible because upon drug removal resistant cells regain sensitivity to AKT inhibition, accompanied by reexpression of epithelial markers and reduction of AKT3 expression, implying that epigenetic reprogramming contributes to acquisition of resistance. These findings provide a rationale for developing therapeutics targeting AKT3 to circumvent acquired resistance in breast cancer. Mol Cancer Ther; 15(8); 1964–74. ©2016 AACR.
Data from Identification of a Small Molecule That Overcomes HdmX-Mediated Suppression of p53
Authors: Karan Goutam , Wang Huaiyu , Chakrabarti Amit , Karan Sukanya , Liu Zhigang , Xia Zhiqiang , Gundluru Mahesh , Moreton Stephen , Saunthararajah Yogen , Jackson Mark W. , Agarwal Mukesh K. , Wald David N.
Published: April 2023

Abstract
Inactivation of the p53 tumor suppressor by mutation or overexpression of negative regulators occurs frequently in cancer. As p53 plays a key role in regulating proliferation or apoptosis in response to DNA-damaging chemotherapies, strategies aimed at reactivating p53 are increasingly being sought. Strategies to reactivate wild-type p53 include the use of small molecules capable of releasing wild-type p53 from key, cellular negative regulators, such as Hdm2 and HdmX. Derivatives of the Hdm2 antagonist Nutlin-3 are in clinical trials. However, Nutlin-3 specifically disrupts Hdm2-p53, leaving tumors harboring high levels of HdmX resistant to Nutlin-3 treatment. Here, we identify CTX1, a novel small molecule that overcomes HdmX-mediated p53 repression. CTX1 binds directly to HdmX to prevent p53–HdmX complex formation, resulting in the rapid induction of p53 in a DNA damage–independent manner. Treatment of a panel of cancer cells with CTX1 induced apoptosis or suppressed proliferation and, importantly, CTX1 demonstrates promising activity as a single agent in a mouse model of circulating primary human leukemia. CTX1 is a small molecule HdmX inhibitor that demonstrates promise as a cancer therapeutic candidate. Mol Cancer Ther; 15(4); 574–82. ©2016 AACR.
Data from Intermittent High-Dose Scheduling of AZD8835, a Novel Selective Inhibitor of PI3Kα and PI3Kδ, Demonstrates Treatment Strategies for PIK3CA-Dependent Breast Cancers
Authors: Hudson Kevin , Hancox Urs J. , Trigwell Cath , McEwen Robert , Polanska Urszula M. , Nikolaou Myria , Morentin Gutierrez Pablo , Avivar-Valderas Alvaro , Delpuech Oona , Dudley Phillippa , Hanson Lyndsey , Ellston Rebecca , Jones Alys , Cumberbatch Marie , Cosulich Sabina C. , Ward Lara , Cruzalegui Francisco , Green Stephen
Published: April 2023

Abstract
The PIK3CA gene, encoding the p110α catalytic unit of PI3Kα, is one of the most frequently mutated oncogenes in human cancer. Hence, PI3Kα is a target subject to intensive efforts in identifying inhibitors and evaluating their therapeutic potential. Here, we report studies with a novel PI3K inhibitor, AZD8835, currently in phase I clinical evaluation. AZD8835 is a potent inhibitor of PI3Kα and PI3Kδ with selectivity versus PI3Kβ, PI3Kγ, and other kinases that preferentially inhibited growth in cells with mutant PIK3CA status, such as in estrogen receptor–positive (ER+) breast cancer cell lines BT474, MCF7, and T47D (sub-μmol/L GI50s). Consistent with this, AZD8835 demonstrated antitumor efficacy in corresponding breast cancer xenograft models when dosed continuously. In addition, an alternative approach of intermittent high-dose scheduling (IHDS) was explored given our observations that higher exposures achieved greater pathway inhibition and induced apoptosis. Indeed, using IHDS, monotherapy AZD8835 was able to induce tumor xenograft regression. Furthermore, AZD8835 IHDS in combination with other targeted therapeutic agents further enhanced antitumor activity (up to 92% regression). Combination partners were prioritized on the basis of our mechanistic insights demonstrating signaling pathway cross-talk, with a focus on targeting interdependent ER and/or CDK4/6 pathways or alternatively a node (mTOR) in the PI3K-pathway, approaches with demonstrated clinical benefit in ER+ breast cancer patients. In summary, AZD8835 IHDS delivers strong antitumor efficacy in a range of combination settings and provides a promising alternative to continuous dosing to optimize the therapeutic index in patients. Such schedules merit clinical evaluation. Mol Cancer Ther; 15(5); 877–89. ©2016 AACR.
Data from The T197A Knock-in Model of Cdkn1b Gene to Study the Effects of p27 Restoration In Vivo
Authors: De Marco Carmela , Rinaldo Nicola , De Vita Fernanda , Forzati Floriana , Caira Elvira , Iovane Valentina , Paciello Orlando , Montanaro Donatella , D'Andrea Sara , Baldassarre Gustavo , Papparella Serenella , Malanga Donatella , Baldi Alfonso , Viglietto Giuseppe
Published: April 2023

Abstract
The CDK inhibitor, p27kip1, encoded by the Cdkn1b gene can negatively modulate cell proliferation. The control of p27 activity during the cell cycle is regulated at multiple levels, including transcription, translation, and protein stability. The last residue of p27 (threonine 198 in human, threonine 197 in mouse) is involved in the control of protein stability. We have generated a murine knock-in model (Cdkn1bT197A) in which threonine 197 is replaced by alanine, which renders p27 protein highly unstable due to a high rate of proteasomal degradation. Expectedly, Cdkn1bT197A/T197A mice present with increased body size and weight, organomegaly, and multiple organ hyperplasia, similar to what is observed in Cdkn1bKO/KO mice. We investigated the effects exerted by the restoration of normal levels of p27 protein in the tissue of Cdkn1bT197A/T197A mice. We found that proteasome inhibition with bortezomib rescues the hyperplasia induced by the lack of p27 expression in Cdkn1bT197A/T197A but not in Cdkn1bKO/KO mice. However, BAY 11-7082, a proteasome inhibitor that stabilizes IκB but not p27, fails to rescue hyperplasia in Cdkn1bT197A/T197A mice. Bortezomib increases p27 half-life and reduces the proliferation in MEFs derived from Cdkn1bT197A/T197A but not from Cdkn1bWT/WT mice, whereas BAY 11-7082 had no effect on the protein levels of p27 and on the proliferation rate of Cdkn1bT197A/T197A MEFs.

The results presented here demonstrate that Cdkn1bT197A/T197A mice represent an attractive in vivo model to investigate whether the targeting of p27 degradation machinery might prove beneficial in the treatment of a variety of human proliferative disorders caused by increased turnover of p27 protein.