bluuebunny/crossref_metadata_2025 huggingface dataset:
Data from Pharmacological Profile of BI 847325, an Orally Bioavailable, ATP-Competitive Inhibitor of MEK and Aurora Kinases
Authors: Sini Patrizia , Gürtler Ulrich , Zahn Stephan K. , Baumann Christoph , Rudolph Dorothea , Baumgartinger Rosa , Strauss Eva , Haslinger Christian , Tontsch-Grunt Ulrike , Waizenegger Irene C. , Solca Flavio , Bader Gerd , Zoephel Andreas , Treu Matthias , Reiser Ulrich , Garin-Chesa Pilar , Boehmelt Guido , Kraut Norbert , Quant Jens , Adolf Günther R.
Published: March 2024

Abstract
Although the MAPK pathway is frequently deregulated in cancer, inhibitors targeting RAF or MEK have so far shown clinical activity only in BRAF- and NRAS-mutant melanoma. Improvements in efficacy may be possible by combining inhibition of mitogenic signal transduction with inhibition of cell-cycle progression. We have studied the preclinical pharmacology of BI 847325, an ATP-competitive dual inhibitor of MEK and Aurora kinases. Potent inhibition of MEK1/2 and Aurora A/B kinases by BI 847325 was demonstrated in enzymatic and cellular assays. Equipotent effects were observed in BRAF-mutant cells, whereas in KRAS-mutant cells, MEK inhibition required higher concentrations than Aurora kinase inhibition. Daily oral administration of BI 847325 at 10 mg/kg showed efficacy in both BRAF- and KRAS-mutant xenograft models. Biomarker analysis suggested that this effect was primarily due to inhibition of MEK in BRAF-mutant models but of Aurora kinase in KRAS-mutant models. Inhibition of both MEK and Aurora kinase in KRAS-mutant tumors was observed when BI 847325 was administered once weekly at 70 mg/kg. Our studies indicate that BI 847325 is effective in in vitro and in vivo models of cancers with BRAF and KRAS mutation. These preclinical data are discussed in the light of the results of a recently completed clinical phase I trial assessing safety, tolerability, pharmacokinetics, and efficacy of BI 847325 in patients with cancer. Mol Cancer Ther; 15(10); 2388–98. ©2016 AACR.
Data from EGFR and RB1 as Dual Biomarkers in HPV-Negative Head and Neck Cancer
Authors: Beck Tim N. , Georgopoulos Rachel , Shagisultanova Elena I. , Sarcu David , Handorf Elizabeth A. , Dubyk Cara , Lango Miriam N. , Ridge John A. , Astsaturov Igor , Serebriiskii Ilya G. , Burtness Barbara A. , Mehra Ranee , Golemis Erica A.
Published: March 2024

Abstract
Clinical decision making for human papillomavirus (HPV)-negative head and neck squamous cell carcinoma (HNSCC) is predominantly guided by disease stage and anatomic location, with few validated biomarkers. The epidermal growth factor receptor (EGFR) is an important therapeutic target, but its value in guiding therapeutic decision making remains ambiguous. We integrated analysis of clinically annotated tissue microarrays with analysis of data available through the TCGA, to investigate the idea that expression signatures involving EGFR, proteins regulating EGFR function, and core cell-cycle modulators might serve as prognostic or drug response–predictive biomarkers. This work suggests that consideration of the expression of NSDHL and proteins that regulate EGFR recycling in combination with EGFR provides a useful prognostic biomarker set. In addition, inactivation of the tumor suppressor retinoblastoma 1 (RB1), reflected by CCND1/CDK6-inactivating phosphorylation of RB1 at T356, inversely correlated with expression of EGFR in patient HNSCC samples. Moreover, stratification of cases with high EGFR by expression levels of CCND1, CDK6, or the CCND1/CDK6-regulatory protein p16 (CDKN2A) identified groups with significant survival differences. To further explore the relationship between EGFR and RB1-associated cell-cycle activity, we evaluated simultaneous inhibition of RB1 phosphorylation with the CDK4/6 inhibitor palbociclib and of EGFR activity with lapatinib or afatinib. These drug combinations had synergistic inhibitory effects on the proliferation of HNSCC cells and strikingly limited ERK1/2 phosphorylation in contrast to either agent used alone. In summary, combinations of CDK and EGFR inhibitors may be particularly useful in EGFR and pT356RB1-expressing or CCND1/CDK6-overexpressing HPV-negative HNSCC. Mol Cancer Ther; 15(10); 2486–97. ©2016 AACR.
Data from Human Leukocyte Antigen–Presented Macrophage Migration Inhibitory Factor Is a Surface Biomarker and Potential Therapeutic Target for Ovarian Cancer
Authors: Patterson Andrea M. , Kaabinejadian Saghar , McMurtrey Curtis P. , Bardet Wilfried , Jackson Ken W. , Zuna Rosemary E. , Husain Sanam , Adams Gregory P. , MacDonald Glen , Dillon Rachelle L. , Ames Harold , Buchli Rico , Hawkins Oriana E. , Weidanz Jon A. , Hildebrand William H.
Published: March 2024

Abstract
T cells recognize cancer cells via HLA/peptide complexes, and when disease overtakes these immune mechanisms, immunotherapy can exogenously target these same HLA/peptide surface markers. We previously identified an HLA-A2–presented peptide derived from macrophage migration inhibitory factor (MIF) and generated antibody RL21A against this HLA-A2/MIF complex. The objective of the current study was to assess the potential for targeting the HLA-A2/MIF complex in ovarian cancer. First, MIF peptide FLSELTQQL was eluted from the HLA-A2 of the human cancerous ovarian cell lines SKOV3, A2780, OV90, and FHIOSE118hi and detected by mass spectrometry. By flow cytometry, RL21A was shown to specifically stain these four cell lines in the context of HLA-A2. Next, partially matched HLA-A*02:01+ ovarian cancer (n = 27) and normal fallopian tube (n = 24) tissues were stained with RL21A by immunohistochemistry to assess differential HLA-A2/MIF complex expression. Ovarian tumor tissues revealed significantly increased RL21A staining compared with normal fallopian tube epithelium (P < 0.0001), with minimal staining of normal stroma and blood vessels (P < 0.0001 and P < 0.001 compared with tumor cells) suggesting a therapeutic window. We then demonstrated the anticancer activity of toxin-bound RL21A via the dose-dependent killing of ovarian cancer cells. In summary, MIF-derived peptide FLSELTQQL is HLA-A2–presented and recognized by RL21A on ovarian cancer cell lines and patient tumor tissues, and targeting of this HLA-A2/MIF complex with toxin-bound RL21A can induce ovarian cancer cell death. These results suggest that the HLA-A2/MIF complex should be further explored as a cell-surface target for ovarian cancer immunotherapy. Mol Cancer Ther; 15(2); 313–22. ©2015 AACR.
Data from The DNA Repair Inhibitor DT01 as a Novel Therapeutic Strategy for Chemosensitization of Colorectal Liver Metastasis
Authors: Herath Nirmitha I. , Devun Flavien , Lienafa Marie-Christine , Herbette Aurélie , Denys Alban , Sun Jian-Sheng , Dutreix Marie
Published: March 2024

Abstract
Metastatic liver disease from colorectal cancer is a significant clinical problem. This is mainly attributed to nonresectable metastases that frequently display low sensitivities to available chemotherapies and develop drug resistance partly via hyperactivation of some DNA repair functions. Combined therapies have shown some disease control; however, there is still a need for more efficient chemotherapies to achieve eradication of colorectal cancer liver metastasis. We investigated the tolerance and efficacy of a novel class of DNA repair inhibitors, Dbait, in association with conventional chemotherapy. Dbait mimics double-strand breaks and activates damage signaling, consequently inhibiting single- and double-stranded DNA repair enzyme recruitment. In vitro, Dbait treatment increases sensitivity of HT29 and HCT116 colorectal cancer cell lines. In vivo, the pharmacokinetics, biodistribution and the efficacy of the cholesterol-conjugated clinical form of Dbait, DT01, were assessed. The chemosensitizing abilities of DT01 were evaluated in association with oxaliplatin and 5-fluorouracil in intrahepatic HT29 xenografted mice used as a model for colorectal cancer liver metastasis. The high uptake of DT01 indicates that the liver is a specific target. We demonstrate significant antitumor efficacy in a liver metastasis model with DT01 treatment in combination with oxaliplatin and 5-fluorouracil (mean: 501 vs. 872 mm2, P = 0.02) compared to chemotherapy alone. The decrease in tumor volume is further associated with significant histologic changes in necrosis, proliferation, angiogenesis and apoptosis. Repeated cycles of DT01 do not increase chemotherapy toxicity. Combining DT01 with conventional chemotherapy may prove to be a safe and effective therapeutic strategy in the treatment of metastatic liver cancer. Mol Cancer Ther; 15(1); 15–22. ©2015 AACR.
Data from Lurbinectedin Specifically Triggers the Degradation of Phosphorylated RNA Polymerase II and the Formation of DNA Breaks in Cancer Cells
Authors: Santamaría Nuñez Gema , Robles Carlos Mario Genes , Giraudon Christophe , Martínez-Leal Juan Fernando , Compe Emmanuel , Coin Frédéric , Aviles Pablo , Galmarini Carlos María , Egly Jean-Marc
Published: March 2024

Abstract
We have defined the mechanism of action of lurbinectedin, a marine-derived drug exhibiting a potent antitumor activity across several cancer cell lines and tumor xenografts. This drug, currently undergoing clinical evaluation in ovarian, breast, and small cell lung cancer patients, inhibits the transcription process through (i) its binding to CG-rich sequences, mainly located around promoters of protein-coding genes; (ii) the irreversible stalling of elongating RNA polymerase II (Pol II) on the DNA template and its specific degradation by the ubiquitin/proteasome machinery; and (iii) the generation of DNA breaks and subsequent apoptosis. The finding that inhibition of Pol II phosphorylation prevents its degradation and the formation of DNA breaks after drug treatment underscores the connection between transcription elongation and DNA repair. Our results not only help to better understand the high specificity of this drug in cancer therapy but also improve our understanding of an important transcription regulation mechanism. Mol Cancer Ther; 15(10); 2399–412. ©2016 AACR.
Data from Sorafenib Suppresses JNK-Dependent Apoptosis through Inhibition of ZAK
Authors: Vin Harina , Ching Grace , Ojeda Sandra S. , Adelmann Charles H. , Chitsazzadeh Vida , Dwyer David W. , Ma Haiching , Ehrenreiter Karin , Baccarini Manuela , Ruggieri Rosamaria , Curry Jonathan L. , Ciurea Ana M. , Duvic Madeleine , Busaidy Naifa L. , Tannir Nizar M. , Tsai Kenneth Y.
Published: March 2024

Abstract
Sorafenib is U.S. Food and Drug Adminstration–approved for the treatment of renal cell carcinoma and hepatocellular carcinoma and has been combined with numerous other targeted therapies and chemotherapies in the treatment of many cancers. Unfortunately, as with other RAF inhibitors, patients treated with sorafenib have a 5% to 10% rate of developing cutaneous squamous cell carcinoma (cSCC)/keratoacanthomas. Paradoxical activation of extracellular signal–regulated kinase (ERK) in BRAF wild-type cells has been implicated in RAF inhibitor–induced cSCC. Here, we report that sorafenib suppresses UV-induced apoptosis specifically by inhibiting c-jun–NH2–kinase (JNK) activation through the off-target inhibition of leucine zipper and sterile alpha motif–containing kinase (ZAK). Our results implicate suppression of JNK signaling, independent of the ERK pathway, as an additional mechanism of adverse effects of sorafenib. This has broad implications for combination therapies using sorafenib with other modalities that induce apoptosis. Mol Cancer Ther; 13(1); 221–9. ©2013 AACR.
Data from A Novel Galectin-1 Inhibitor Discovered through One-Bead Two-Compound Library Potentiates the Antitumor Effects of Paclitaxel in vivo
Authors: Shih Tsung-Chieh , Liu Ruiwu , Fung Gabriel , Bhardwaj Gaurav , Ghosh Paramita M. , Lam Kit S.
Published: March 2024

Abstract
Through the one-bead two-compound (OB2C) ultra–high-throughput screening method, we discovered a new small-molecule compound LLS2 that can kill a variety of cancer cells. Pull-down assay and LC/MS-MS indicated that galectin-1 is the target protein of LLS2. Galectin-1 is known to be involved in the regulation of proliferation, apoptosis, cell cycle, and angiogenesis. Binding of LLS2 to galectin-1 decreased membrane-associated H-Ras and K-Ras and contributed to the suppression of pErk pathway. Importantly, combination of LLS2 with paclitaxel (a very important clinical chemotherapeutic agent) was found to exhibit synergistic activity against several human cancer cell lines (ovarian cancer, pancreatic cancer, and breast cancer cells) in vitro. Furthermore, in vivo therapeutic study indicated that combination treatment with paclitaxel and LLS2 significantly inhibits the growth of ovarian cancer xenografts in athymic mice. Our results presented here indicate that the OB2C combinatorial technology is a highly efficient drug screening platform, and LLS2 discovered through this method can be further optimized for anticancer drug development. Mol Cancer Ther; 16(7); 1212–23. ©2017 AACR.
Data from Combining Antibody-Directed Presentation of IL-15 and 4-1BBL in a Trifunctional Fusion Protein for Cancer Immunotherapy
Authors: Kermer Vanessa , Hornig Nora , Harder Markus , Bondarieva Anastasiia , Kontermann Roland E. , Müller Dafne
Published: March 2024

Abstract
Influencing the cytokine receptor network that modulates the immune response holds great potential for cancer immunotherapy. Although encouraging results have been obtained by focusing on individual members of the common γ-chain (γc) receptor family and TNF receptor superfamily so far, combination strategies might be required to further improve the effectiveness of the antitumor response. Here, we propose the combination of interleukin (IL)-15 and 4-1BBL in a single, tumor-directed molecule. Therefore, a trifunctional antibody fusion protein was generated, composed of a tumor-specific recombinant antibody, IL-15 linked to a fragment of the IL-15Rα chain (RD) and the extracellular domain of 4-1BBL. In soluble and targeted forms, the trifunctional antibody fusion protein RD_IL-15_scFv_4-1BBL was shown to stimulate activated T-cell proliferation and induce T-cell cytotoxicity to a similar degree as the bifunctional scFv_RD_IL-15 fusion protein. On the other hand, in targeted form, the trifunctional fusion protein was much more effective in inducing T-cell proliferation and IFN-γ release of unstimulated peripheral blood mononuclear cells (PBMC). Here, the additional signal enhancement could be attributed to the costimulatory activity of 4-1BBL, indicating a clear benefit for the simultaneous presentation of IL-15 and 4-1BBL in one molecule. Furthermore, the trifunctional antibody fusion protein was more effective than the corresponding bifunctional fusion proteins in reducing metastases in a tumor mouse model in vivo. Hence, the targeted combination of IL-15 and 4-BBL in the form of a trifunctional antibody-fusion protein is a promising new approach for cancer immunotherapy. Mol Cancer Ther; 13(1); 112–21. ©2013 AACR.
Data from Targeted Photodynamic Virotherapy Armed with a Genetically Encoded Photosensitizer
Authors: Takehara Kiyoto , Tazawa Hiroshi , Okada Naohiro , Hashimoto Yuuri , Kikuchi Satoru , Kuroda Shinji , Kishimoto Hiroyuki , Shirakawa Yasuhiro , Narii Nobuhiro , Mizuguchi Hiroyuki , Urata Yasuo , Kagawa Shunsuke , Fujiwara Toshiyoshi
Published: March 2024

Abstract
Photodynamic therapy (PDT) is a minimally invasive antitumor therapy that eradicates tumor cells through a photosensitizer-mediated cytotoxic effect upon light irradiation. However, systemic administration of photosensitizer often makes it difficult to avoid a photosensitive adverse effect. The red fluorescent protein KillerRed generates reactive oxygen species (ROS) upon green light irradiation. Here, we show the therapeutic potential of a novel tumor-specific replicating photodynamic viral agent (TelomeKiller) constructed using the human telomerase reverse transcriptase (hTERT) promoter. We investigated the light-induced antitumor effect of TelomeKiller in several types of human cancer cell lines. Relative cell viability was investigated using an XTT assay. The in vivo antitumor effect was assessed using subcutaneous xenografted tumor and lymph node metastasis models. KillerRed accumulation resulted in ROS generation and apoptosis in light-irradiated cancer cells. Intratumoral injection of TelomeKiller efficiently delivered the KillerRed protein throughout the tumors and exhibited a long-lasting antitumor effect with repeated administration and light irradiation in mice. Moreover, intratumorally injected TelomeKiller could spread into the regional lymph node area and eliminate micrometastasis with limited-field laser irradiation. Our results suggest that KillerRed has great potential as a novel photosensitizer if delivered with a tumor-specific virus-mediated delivery system. TelomeKiller-based PDT is a promising antitumor strategy to efficiently eradicate tumor cells. Mol Cancer Ther; 15(1); 199–208. ©2015 AACR.
Data from Identification of Novel Radiosensitizers in a High-Throughput, Cell-Based Screen for DSB Repair Inhibitors
Authors: Goglia Alexander G. , Delsite Robert , Luz Antonio N. , Shahbazian David , Salem Ahmed F. , Sundaram Ranjini K. , Chiaravalli Jeanne , Hendrikx Petrus J. , Wilshire Jennifer A. , Jasin Maria , Kluger Harriet M. , Glickman J. Fraser , Powell Simon N. , Bindra Ranjit S.
Published: March 2024

Abstract
Most cancer therapies involve a component of treatment that inflicts DNA damage in tumor cells, such as double-strand breaks (DSBs), which are considered the most serious threat to genomic integrity. Complex systems have evolved to repair these lesions, and successful DSB repair is essential for tumor cell survival after exposure to ionizing radiation (IR) and other DNA-damaging agents. As such, inhibition of DNA repair is a potentially efficacious strategy for chemo- and radiosensitization. Homologous recombination (HR) and nonhomologous end-joining (NHEJ) represent the two major pathways by which DSBs are repaired in mammalian cells. Here, we report the design and execution of a high-throughput, cell-based small molecule screen for novel DSB repair inhibitors. We miniaturized our recently developed dual NHEJ and HR reporter system into a 384-well plate-based format and interrogated a diverse library of 20,000 compounds for molecules that selectively modulate NHEJ and HR repair in tumor cells. We identified a collection of novel hits that potently inhibit DSB repair, and we have validated their functional activity in a comprehensive panel of orthogonal secondary assays. A selection of these inhibitors was found to radiosensitize cancer cell lines in vitro, which suggests that they may be useful as novel chemo- and radio sensitizers. Surprisingly, we identified several FDA-approved drugs, including the calcium channel blocker mibefradil dihydrochloride, that demonstrated activity as DSB repair inhibitors and radiosensitizers. These findings suggest the possibility for repurposing them as tumor cell radiosensitizers in the future. Accordingly, we recently initiated a phase I clinical trial testing mibefradil as a glioma radiosensitizer. Mol Cancer Ther; 14(2); 326–42. ©2014 AACR.
Data from Differential and Common DNA Repair Pathways for Topoisomerase I- and II-Targeted Drugs in a Genetic DT40 Repair Cell Screen Panel
Authors: Maede Yuko , Shimizu Hiroyasu , Fukushima Toru , Kogame Toshiaki , Nakamura Terukazu , Miki Tsuneharu , Takeda Shunichi , Pommier Yves , Murai Junko
Published: March 2024

Abstract
Clinical topoisomerase I (Top1) and II (Top2) inhibitors trap topoisomerases on DNA, thereby inducing protein-linked DNA breaks. Cancer cells resist the drugs by removing topoisomerase-DNA complexes, and repairing the drug-induced DNA double-strand breaks (DSB) by homologous recombination and nonhomologous end joining (NHEJ). Because numerous enzymes and cofactors are involved in the removal of the topoisomerase-DNA complexes and DSB repair, it has been challenging to comprehensively analyze the relative contribution of multiple genetic pathways in vertebrate cells. Comprehending the relative contribution of individual repair factors would give insights into the lesions induced by the inhibitors and genetic determinants of response. Ultimately, this information would be useful to target specific pathways to augment the therapeutic activity of topoisomerase inhibitors. To this end, we put together 48 isogenic DT40 mutant cells deficient in DNA repair and generated one cell line deficient in autophagy (ATG5). Sensitivity profiles were established for three clinically relevant Top1 inhibitors (camptothecin and the indenoisoquinolines LMP400 and LMP776) and three Top2 inhibitors (etoposide, doxorubicin, and ICRF-193). Highly significant correlations were found among Top1 inhibitors as well as Top2 inhibitors, whereas the profiles of Top1 inhibitors were different from those of Top2 inhibitors. Most distinct repair pathways between Top1 and Top2 inhibitors include NHEJ, TDP1, TDP2, PARP1, and Fanconi Anemia genes, whereas homologous recombination seems relevant especially for Top1 and, to a lesser extent, for Top2 inhibitors. We also found and discuss differential pathways among Top1 inhibitors and Top2 inhibitors. Mol Cancer Ther; 13(1); 214–20. ©2013 AACR.
Data from Edelfosine Promotes Apoptosis in Androgen-Deprived Prostate Tumors by Increasing ATF3 and Inhibiting Androgen Receptor Activity
Authors: Udayakumar Thirupandiyur S. , Stoyanova Radka , Shareef Mohammed M. , Mu Zhaomei , Philip Sakhi , Burnstein Kerry L. , Pollack Alan
Published: March 2024

Abstract
Edelfosine is a synthetic alkyl-lysophospholipid that possesses significant antitumor activity in several human tumor models. Here, we investigated the effects of edelfosine combined with androgen deprivation (AD) in LNCaP and VCaP human prostate cancer cells. This treatment regimen greatly decreased cell proliferation compared with single agent or AD alone, resulting in higher levels of apoptosis in LNCaP compared with VCaP cells. Edelfosine caused a dose-dependent decrease in AKT activity, but did not affect the expression of total AKT in either cell line. Furthermore, edelfosine treatment inhibited the expression of androgen receptor (AR) and was associated with an increase in activating transcription factor 3 (ATF3) expression levels, a stress response gene and a negative regulator of AR transactivation. ATF3 binds to AR after edelfosine + AD and represses the transcriptional activation of AR as demonstrated by PSA promoter studies. Knockdown of ATF3 using siRNA-ATF3 reversed the inhibition of PSA promoter activity, suggesting that the growth inhibition effect of edelfosine was ATF3 dependent. Moreover, expression of AR variant 7 (ARv7) and TMPRSS2-ERG fusion gene were greatly inhibited after combined treatment with AD and edelfosine in VCaP cells. In vivo experiments using an orthotopic LNCaP model confirmed the antitumor effects of edelfosine + AD over the individual treatments. A significant decrease in tumor volume and PSA levels was observed when edelfosine and AD were combined, compared with edelfosine alone. Edelfosine shows promise in combination with AD for the treatment of prostate cancer patients. Mol Cancer Ther; 15(6); 1353–63. ©2016 AACR.
Data from Silibinin Preferentially Radiosensitizes Prostate Cancer by Inhibiting DNA Repair Signaling
Authors: Nambiar Dhanya K. , Rajamani Paulraj , Deep Gagan , Jain Anil K. , Agarwal Rajesh , Singh Rana P.
Published: March 2024

Abstract
Radiotherapy, a frequent mode of cancer treatment, is often restricted by dose-related toxicity and development of therapeutic resistance. To develop a novel and selective radiosensitizer, we studied the radiosensitizing effects and associated mechanisms of silibinin in prostate cancer. The radiosensitizing effect of silibinin with ionizing radiation (IR) was assessed on radioresistant prostate cancer cell lines by clonogenic, cell cycle, cell death, and DNA repair assays. Tumor xenograft growth, immunohistochemical (IHC) analysis of tumor tissues, and toxicity-related parameters were measured in vivo. Silibinin (25 μmol/L) enhanced IR (2.5–10 Gy)-caused inhibition (up to 96%, P < 0.001) of colony formation selectively in prostate cancer cells, and prolonged and enhanced IR-caused G2–M arrest, apoptosis, and ROS production. Mechanistically, silibinin inhibited IR-induced DNA repair (ATM and Chk1/2) and EGFR signaling and attenuated the levels of antiapoptotic proteins. Specifically, silibinin suppressed IR-induced nuclear translocation of EGFR and DNA-PK, an important mediator of DSB repair, leading to an increased number of γ-H2AX (ser139) foci suggesting lesser DNA repair. In vivo, silibinin strongly radiosensitized DU145 tumor xenograft inhibition (84%, P < 0.01) with higher apoptotic response (10-fold, P < 0.01) and reduced repair of DNA damage, and rescued the mice from IR-induced toxicity and hematopoietic injury. Overall, silibinin enhanced the radiotherapeutic response via suppressing IR-induced prosurvival signaling and DSB repair by inhibiting nuclear translocation of EGFR and DNA-PK. Because silibinin is already in phase II clinical trial for prostate cancer patients, the present finding has translational relevance for radioresistant prostate cancer. Mol Cancer Ther; 14(12); 2722–34. ©2015 AACR.
Data from Targeting the Neurokinin-1 Receptor Compromises Canonical Wnt Signaling in Hepatoblastoma
Authors: Ilmer Matthias , Garnier Agnès , Vykoukal Jody , Alt Eckhard , von Schweinitz Dietrich , Kappler Roland , Berger Michael
Published: March 2024

Abstract
The substance P (SP)/NK-1 receptor (NK1R) complex represents an intriguing anticancer target for a variety of tumors, including hepatoblastoma (HB). Therefore, NK1R antagonists, such as the clinical drug aprepitant, recently have been proposed as potent anticancer agents. However, very little is known regarding the molecular basis of NK1R inhibition in cancer. Using reverse phase protein array, Western blot, Super TOP/FOP, confocal microscopy, and sphere formation ability (SFA) assays, we identified the AKT and Wnt signaling pathways as the key targets of aprepitant in three human HB cell lines (HepT1, HepG2, and HuH6). Following NK1R blockage, we observed decreased phosphorylation of p70S6K and 4E-BP1/2 and inhibition of the canonical Wnt pathway with subsequent decrease of HB cell growth. This effect was dependent of high baseline Wnt activity either by mutational status of β-catenin or extrinsic Wnt activation. Wnt inhibition seemed to be strengthened by disruption of the FOXM1–β-catenin complex. Furthermore, treatment of HB cells with aprepitant led to reduced expression of (liver) stemness markers (AFP, CD13, SOX2, NANOG, and OCT4) and SFA when grown under cancer stem cell conditions. Taken together, we show for the first time that targeting the SP/NK1R signaling cascade inhibits canonical Wnt signaling in HB cells. These findings reveal important insight into the molecular mechanisms of the SP/NK1R complex as a critical component in a model of pediatric liver cancer and may support the development of novel therapeutic interventions for HB and other Wnt-activated cancers. Mol Cancer Ther; 14(12); 2712–21. ©2015 AACR.
Data from ABCG2 and ABCB1 Limit the Efficacy of Dasatinib in a PDGF-B–Driven Brainstem Glioma Model
Authors: Mittapalli Rajendar K. , Chung Alexander H. , Parrish Karen E. , Crabtree Donna , Halvorson Kyle G. , Hu Guo , Elmquist William F. , Becher Oren J.
Published: March 2024

Abstract
Dasatinib is a multikinase inhibitor in clinical trials for glioma, and thus far has failed to demonstrate significant efficacy. We investigated whether the ABC efflux transporters ABCG2 and ABCB1 expressed in the blood–brain barrier (BBB), are limiting the efficacy of dasatinib in the treatment of glioma using genetic and pharmacologic approaches. We utilized a genetic brainstem glioma mouse model driven by platelet-derived growth factor-B and p53 loss using abcg2/abcb1 wild-type (ABC WT) or abcg2/abcb1 knockout mice (ABC KO). First, we observed that brainstem glioma tumor latency is significantly prolonged in ABC KO versus ABC WT mice (median survival of 47 vs. 34 days). Dasatinib treatment nearly doubles the survival of brainstem glioma-bearing ABC KO mice (44 vs. 80 days). Elacridar, an ABCG2 and ABCB1 inhibitor, significantly increases the efficacy of dasatinib in brainstem glioma-bearing ABC WT mice (42 vs. 59 days). Pharmacokinetic analysis demonstrates that dasatinib delivery into the normal brain, but not into the tumor core, is significantly increased in ABC KO mice compared with ABC WT mice. Surprisingly, elacridar did not significantly increase dasatinib delivery into the normal brain or the tumor core of ABC WT mice. Next, we demonstrate that the tight junctions of the BBB of this model are compromised as assessed by tissue permeability to Texas Red dextran. Finally, elacridar increases the cytotoxicity of dasatinib independent of ABCG2 and ABCB1 expression in vitro. In conclusion, elacridar improves the efficacy of dasatinib in a brainstem glioma model without significantly increasing its delivery to the tumor core. Mol Cancer Ther; 15(5); 819–29. ©2016 AACR.
Data from Targeted Drug Delivery with an Integrin-Binding Knottin–Fc–MMAF Conjugate Produced by Cell-Free Protein Synthesis
Authors: Currier Nicolas V. , Ackerman Shelley E. , Kintzing James R. , Chen Rishard , Filsinger Interrante Maria , Steiner Alexander , Sato Aaron K. , Cochran Jennifer R.
Published: March 2024

Abstract
Antibody–drug conjugates (ADC) have generated significant interest as targeted therapeutics for cancer treatment, demonstrating improved clinical efficacy and safety compared with systemic chemotherapy. To extend this concept to other tumor-targeting proteins, we conjugated the tubulin inhibitor monomethyl-auristatin-F (MMAF) to 2.5F–Fc, a fusion protein composed of a human Fc domain and a cystine knot (knottin) miniprotein engineered to bind with high affinity to tumor-associated integrin receptors. The broad expression of integrins (including αvβ3, αvβ5, and α5β1) on tumor cells and their vasculature makes 2.5F-Fc an attractive tumor-targeting protein for drug delivery. We show that 2.5F-Fc can be expressed by cell-free protein synthesis, during which a non-natural amino acid was introduced into the Fc domain and subsequently used for site-specific conjugation of MMAF through a noncleavable linker. The resulting knottin–Fc–drug conjugate (KFDC), termed 2.5F-Fc-MMAF, had approximately 2 drugs attached per KFDC. 2.5F–Fc–MMAF inhibited proliferation in human glioblastoma (U87MG), ovarian (A2780), and breast (MB-468) cancer cells to a greater extent than 2.5F–Fc or MMAF alone or added in combination. As a single agent, 2.5F–Fc–MMAF was effective at inducing regression and prolonged survival in U87MG tumor xenograft models when administered at 10 mg/kg two times per week. In comparison, tumors treated with 2.5F–Fc or MMAF were nonresponsive, and treatment with a nontargeted control, CTRL–Fc–MMAF, showed a modest but not significant therapeutic effect. These studies provide proof-of-concept for further development of KFDCs as alternatives to ADCs for tumor targeting and drug delivery applications. Mol Cancer Ther; 15(6); 1291–300. ©2016 AACR.
Data from Irreversible Inhibition of EGFR: Modeling the Combined Pharmacokinetic–Pharmacodynamic Relationship of Osimertinib and Its Active Metabolite AZ5104
Authors: Yates James W.T. , Ashton Susan , Cross Darren , Mellor Martine J. , Powell Steve J. , Ballard Peter
Published: March 2024

Abstract
Osimertinib (AZD9291) is a potent, selective, irreversible inhibitor of EGFR-sensitizing (exon 19 and L858R) and T790M-resistant mutation. In vivo, in the mouse, it is metabolized to an active des-methyl metabolite, AZ5104. To understand the therapeutic potential in patients, this study aimed to assess the relationship between osimertinib pharmacokinetics, the pharmacokinetics of the active metabolite, the pharmacodynamics of phosphorylated EGFR reduction, and efficacy in mouse xenograft models of EGFR-driven cancers, including two NSCLC lines. Osimertinib was dosed in xenografted models of EGFR-driven cancers. In one set of experiments, changes in phosphorylated EGFR were measured to confirm target engagement. In a second set of efficacy studies, the resulting changes in tumor volume over time after repeat dosing of osimertinib were observed. To account for the contributions of both molecules, a mathematical modeling approach was taken to integrate the resulting datasets. The model was able to describe the pharmacokinetics, pharmacodynamics, and efficacy in A431, PC9, and NCI-H1975 xenografts, with the differences in sensitivity described by the varying potency against wild-type, sensitizing, and T790M-mutant EGFR and the phosphorylated EGFR reduction required to reduce tumor volume. It was inferred that recovery of pEGFR is slower after chronic dosing due to reduced resynthesis. It was predicted and further demonstrated that although inhibition is irreversible, the resynthesis of EGFR is such that infrequent intermittent dosing is not as efficacious as once daily dosing. Mol Cancer Ther; 15(10); 2378–87. ©2016 AACR.
Data from The Role of HMGB1 in Radioresistance of Bladder Cancer
Authors: Shrivastava Sanhita , Mansure Jose Joao , Almajed Wael , Cury Fabio , Ferbeyre Gerardo , Popovic Marija , Seuntjens Jan , Kassouf Wassim
Published: March 2024

Abstract
Although radical cystectomy surgery is the standard-of-care for muscle-invasive bladder cancer, it entails complete removal of the bladder and surrounding organs which leads to substantial loss in the quality-of-life of patients. Radiotherapy, which spares the bladder, would be a more appropriate treatment modality if we can utilize molecular markers to select patients with better response to radiation. In this study, we investigate a protein called high mobility group box protein 1 (HMGB1) as a predictive marker for radiotherapy response in bladder cancer. Our in vitro results indicate a positive correlation between higher levels of HMGB1 protein and resistance to radiation in various cell lines. Upon HMGB1 protein knockdown, highly significant (>1.5-fold) sensitization to radiotherapy was achieved. We saw that loss of HMGB1 was associated with at least two times higher (P < 0.001) DNA damage in cell lines postradiation. Our results also depicted that autophagy was inhibited more than 3-fold (P < 0.001) upon HMGB1 knockdown, implicating its role in autophagy as another cause of bladder cancer radioresistance. Further validation was done in vivo by conducting mouse tumor xenograft experiments, where HMGB1 knockdown tumors showed a significantly better (P < 0.001) response to radiotherapy and decreased autophagy (shown by P62 staining) as compared with controls. The cumulative findings of our in vitro and in vivo studies highlight the significance of HMGB1 as a radiation response marker as well as its utility in radiosensitization of bladder cancer. Mol Cancer Ther; 15(3); 471–9. ©2015 AACR.
Data from RON Nuclear Translocation under Hypoxia Potentiates Chemoresistance to DNA Double-Strand Break–Inducing Anticancer Drugs
Authors: Chang Hong-Yi , Chang Ting-Chia , Huang Wen-Ya , Lee Chung-Ta , Yen Chia-Jui , Tsai Yuh-Shyan , Tzai Tzong-Shin , Chen Shu-Hui , Chow Nan-Haw
Published: March 2024

Abstract
Tumor hypoxia is associated with radioresistance, chemoresistance, and metastasis, which eventually lead to cancer progression and a poor patient prognosis. RON [also known as macrophage-stimulating protein receptor (MST1R)] belongs to the c-MET [also known as hepatocyte growth factor receptor (HGFR)] receptor tyrosine kinase (RTK) superfamily. To identify the interaction partners of RON nuclear translocation in response to hypoxia, the nuclear extract of TSGH8301 bladder cancer cells was immunoprecipitated for tandem mass profiling analysis. Nuclear RON interacted with adenosine triphosphate (ATP)-dependent DNA helicase 2 (Ku70) and DNA-dependent protein kinase catalytic subunit (DNA-PKcs) to activate nonhomologous end joining (NHEJ) DNA repair. The interaction was time dependent, extending 3 to 24 hours posthypoxia or until the components had been exposed to the chemotherapeutic drugs doxorubicin and epirubicin. Stable knockdown experiments in vitro suggest the importance of RON for the chemoresistance of cancer cells under hypoxia. In addition, the tyrosine kinase domain of nuclear RON is crucial for interaction with Ku70 under hypoxia. J82 cells transfected with RON showed a survival advantage in the presence of epirubicin and hypoxia. This suggests that nuclear RON activates NHEJ repair by interacting with Ku70/DNA-PKcs and inhibiting RON activity to increase cancer cell chemosensitivity. Mol Cancer Ther; 15(2); 276–86. ©2016 AACR.
Data from A New Class of Bifunctional Major Histocompatibility Class I Antibody Fusion Molecules to Redirect CD8 T Cells
Authors: Schmittnaegel Martina , Hoffmann Eike , Imhof-Jung Sabine , Fischer Cornelia , Drabner Georg , Georges Guy , Klein Christian , Knoetgen Hendrik
Published: March 2024

Abstract
Bifunctional antibody fusion proteins engaging effector T cells for targeted elimination of tumor cells via CD3 binding have shown efficacy in both preclinical and clinical studies. Different from such a polyclonal T-cell recruitment, an alternative concept is to engage only antigen-specific T-cell subsets. Recruitment of specific subsets of T cells may be as potent but potentially lead to fewer side effects. Tumor-targeted peptide–MHC class I complexes (pMHCI-IgGs) bearing known antigenic peptides complexed with MHC class I molecules mark tumor cells as antigenic and utilize the physiologic way to interact with and activate T-cell receptors. If, for example, virus-specific CD8+ T cells are addressed, the associated strong antigenicity and tight immune surveillance of the effector cells could lead to efficacious antitumor treatment in various tissues. However, peptide–MHC class I fusions are difficult to express recombinantly, especially when fused to entire antibody molecules. Consequently, current formats are largely limited to small antibody fragment fusions expressed in bacteria followed by refolding or chemical conjugation. Here, we describe a new molecular format bearing a single pMHCI complex per IgG fusion molecule characterized by enhanced stability and expression yields. This molecular format can be expressed in a full immunoglobulin format and can be designed as mono- or bivalent antibody binders. Mol Cancer Ther; 15(9); 2130–42. ©2016 AACR.
Data from High XIST and Low 53BP1 Expression Predict Poor Outcome after High-Dose Alkylating Chemotherapy in Patients with a BRCA1-like Breast Cancer
Authors: Schouten Philip C. , Vollebergh Marieke A. , Opdam Mark , Jonkers Martijn , Loden Martin , Wesseling Jelle , Hauptmann Michael , Linn Sabine C.
Published: March 2024

Abstract
In previous studies, high expression of XIST and low expression of 53BP1 were respectively associated with poor systemic therapy outcome in patients and therapy resistance in BRCA1-deficient mouse tumor models, but have not been evaluated in BRCA1-deficient patients. Previously, we demonstrated that classifying breast cancer copy number profiles as BRCA1-like or non–BRCA1-like identified patients enriched for defects in BRCA1 that benefit from high-dose (HD) alkylating chemotherapy compared with a conventional standard regimen. We investigated whether XIST and 53BP1 expression predicted poor outcome of HD chemotherapy within 28 BRCA1-like patients from a trial randomizing between HD [4 cycles 5-fluorouracil, epirubicin, cyclophosphamide (FEC) followed by 1 cycle HD carboplatin, thiotepa, cyclophosphamide] or conventional chemotherapy (5 cycles FEC), for which both XIST and 53BP1 statuses were available. High RNA expression of XIST (n = 5) and low protein expression of 53BP1 (n = 3) expression did not coincide. Patients with either one had poor outcome after treatment with HD chemotherapy, whereas patients with low expression of XIST and high expression of 53BP1 derived substantial benefit of this regimen on recurrence-free survival, disease-free survival, and overall survival, corroborating preclinical findings. XIST and 53BP1 may be predictive biomarkers in BRCA1-like breast cancer. Mol Cancer Ther; 15(1); 190–8. ©2015 AACR.
Data from MOR209/ES414, a Novel Bispecific Antibody Targeting PSMA for the Treatment of Metastatic Castration-Resistant Prostate Cancer
Authors: Hernandez-Hoyos Gabriela , Sewell Toddy , Bader Robert , Bannink Jeannette , Chenault Ruth A. , Daugherty Mollie , Dasovich Maria , Fang Hang , Gottschalk Rebecca , Kumer John , Miller Robert E. , Ravikumar Padma , Wiens Jennifer , Algate Paul A. , Bienvenue David , McMahan Catherine J. , Natarajan Sateesh K. , Gross Jane A. , Blankenship John W.
Published: March 2024

Abstract
Treatment of metastatic, castration-resistant prostate cancer (mCRPC) remains a highly unmet medical need and current therapies ultimately result in disease progression. Immunotherapy is a rapidly growing approach for treatment of cancer but has shown limited success to date in the treatment of mCRPC. We have developed a novel humanized bispecific antibody, MOR209/ES414, built on the ADAPTIR (modular protein technology) platform, to redirect T-cell cytotoxicity toward prostate cancer cells by specifically targeting T cells through CD3ϵ to prostate cancer cells expressing PSMA (prostate-specific membrane antigen). In vitro cross-linking of T cells with PSMA-expressing tumor cells by MOR209/ES414 triggered potent target-dependent tumor lysis and induction of target-dependent T-cell activation and proliferation. This activity occurred at low picomolar concentrations of MOR209/ES414 and was effective at low T-effector to tumor target cell ratios. In addition, cytotoxic activity was equivalent over a wide range of PSMA expression on target cells, suggesting that as few as 3,700 PSMA receptors per cell are sufficient for tumor lysis. In addition to high sensitivity and in vitro activity, MOR209/ES414 induced limited production of cytokines compared with other bispecific antibody formats. Pharmacokinetic analysis of MOR209/ES414 demonstrated a serum elimination half-life in NOD/SCID γ (NSG) mice of 4 days. Administration of MOR209/ES414 in murine xenograft models of human prostate cancer significantly inhibited tumor growth, prolonged survival, and decreased serum prostate-specific antigen levels only in the presence of adoptively transferred human T cells. On the basis of these preclinical findings, MOR209/ES414 warrants further investigation as a potential therapeutic for the treatment of CRPC. Mol Cancer Ther; 15(9); 2155–65. ©2016 AACR.
Data from Applying Small Molecule Signal Transducer and Activator of Transcription-3 (STAT3) Protein Inhibitors as Pancreatic Cancer Therapeutics
Authors: Arpin Carolyn C. , Mac Stephen , Jiang Yanlin , Cheng Huiwen , Grimard Michelle , Page Brent D.G. , Kamocka Malgorzata M. , Haftchenary Sina , Su Han , Ball Daniel P. , Rosa David A. , Lai Ping-Shan , Gómez-Biagi Rodolfo F. , Ali Ahmed M. , Rana Rahul , Hanenberg Helmut , Kerman Kagan , McElyea Kyle C. , Sandusky George E. , Gunning Patrick T. , Fishel Melissa L.
Published: March 2024

Abstract
Constitutively activated STAT3 protein has been found to be a key regulator of pancreatic cancer and a target for molecular therapeutic intervention. In this study, PG-S3-001, a small molecule derived from the SH-4-54 class of STAT3 inhibitors, was found to inhibit patient-derived pancreatic cancer cell proliferation in vitro and in vivo in the low micromolar range. PG-S3-001 binds the STAT3 protein potently, Kd = 324 nmol/L by surface plasmon resonance, and showed no effect in a kinome screen (>100 cancer-relevant kinases). In vitro studies demonstrated potent cell killing as well as inhibition of STAT3 activation in pancreatic cancer cells. To better model the tumor and its microenvironment, we utilized three-dimensional (3D) cultures of patient-derived pancreatic cancer cells in the absence and presence of cancer-associated fibroblasts (CAF). In this coculture model, inhibition of tumor growth is maintained following STAT3 inhibition in the presence of CAFs. Confocal microscopy was used to verify tumor cell death following treatment of 3D cocultures with PG-S3-001. The 3D model was predictive of in vivo efficacy as significant tumor growth inhibition was observed upon administration of PG-S3-001. These studies showed that the inhibition of STAT3 was able to impact the survival of tumor cells in a relevant 3D model, as well as in a xenograft model using patient-derived cells. Mol Cancer Ther; 15(5); 794–805. ©2016 AACR.
Data from Quantitative Phosphoproteomics Reveals Wee1 Kinase as a Therapeutic Target in a Model of Proneural Glioblastoma
Authors: Lescarbeau Rebecca S. , Lei Liang , Bakken Katrina K. , Sims Peter A. , Sarkaria Jann N. , Canoll Peter , White Forest M.
Published: March 2024

Abstract
Glioblastoma (GBM) is the most common malignant primary brain cancer. With a median survival of about a year, new approaches to treating this disease are necessary. To identify signaling molecules regulating GBM progression in a genetically engineered murine model of proneural GBM, we quantified phosphotyrosine-mediated signaling using mass spectrometry. Oncogenic signals, including phosphorylated ERK MAPK, PI3K, and PDGFR, were found to be increased in the murine tumors relative to brain. Phosphorylation of CDK1 pY15, associated with the G2 arrest checkpoint, was identified as the most differentially phosphorylated site, with a 14-fold increase in phosphorylation in the tumors. To assess the role of this checkpoint as a potential therapeutic target, syngeneic primary cell lines derived from these tumors were treated with MK-1775, an inhibitor of Wee1, the kinase responsible for CDK1 Y15 phosphorylation. MK-1775 treatment led to mitotic catastrophe, as defined by increased DNA damage and cell death by apoptosis. To assess the extensibility of targeting Wee1/CDK1 in GBM, patient-derived xenograft (PDX) cell lines were also treated with MK-1775. Although the response was more heterogeneous, on-target Wee1 inhibition led to decreased CDK1 Y15 phosphorylation and increased DNA damage and apoptosis in each line. These results were also validated in vivo, where single-agent MK-1775 demonstrated an antitumor effect on a flank PDX tumor model, increasing mouse survival by 1.74-fold. This study highlights the ability of unbiased quantitative phosphoproteomics to reveal therapeutic targets in tumor models, and the potential for Wee1 inhibition as a treatment approach in preclinical models of GBM. Mol Cancer Ther; 15(6); 1332–43. ©2016 AACR.