bluuebunny/crossref_metadata_2025 huggingface dataset:
Data from Antitumor Effects in Gastrointestinal Stromal Tumors Using Photodynamic Therapy with a Novel Glucose-Conjugated Chlorin
Authors: Tanaka Mamoru , Kataoka Hiromi , Yano Shigenobu , Ohi Hiromi , Moriwaki Kazuhiro , Akashi Haruo , Taguchi Takahiro , Hayashi Noriyuki , Hamano Shingo , Mori Yoshinori , Kubota Eiji , Tanida Satoshi , Joh Takashi
Published: April 2023

Abstract
Gastrointestinal stromal tumors (GIST) are the most common mesenchymal tumors of the gastrointestinal tract. Except for surgical resection, no effective treatment strategies have been established. Photodynamic therapy (PDT) consists of intravenous administration of a photosensitizer, activated by a specific wavelength of light, which produces reactive oxygen species that directly kill tumor cells. We analyzed the efficacy of PDT using a newly developed photosensitizer, 5,10,15,20-tetrakis [4-[β-d-glucopyranosylthio-2,3,5,6-tetrafluorophenyl]-2,3,[methano[N-methyl] iminomethano] chlorin (H2TFPC-SGlc), for the GIST treatment. Various photosensitizers were administered in vitro to GIST (GIST-T1) and fibroblast (WI-38) cells, followed by irradiation, after which cell death was compared. We additionally established xenograft mouse models with GIST-T1 tumors and examined the accumulation and antitumor effects of these photosensitizers in vivo. In vitro, the expression of the glucose transporters GLUT1, GLUT3, and GLUT4, the cellular uptake of H2TFPC-SGlc, and apoptosis mediated by PDT with H2TFPC-SGlc were significantly higher in GIST-T1 than in WI-38 cells. In vivo, H2TFPC-SGlc accumulation was higher in xenograft tumors of GIST-T1 cells than in the adjacent normal tissue, and tumor growth was significantly suppressed following PDT. PDT with novel H2TFPC-SGlc is potentially useful for clinical applications about the treatment of GIST. Mol Cancer Ther; 13(4); 767–75. ©2014 AACR.
Data from Activity of a Novel Hec1-Targeted Anticancer Compound against Breast Cancer Cell Lines In Vitro and In Vivo
Authors: Huang Lynn Y.L. , Chang Chia-Chi , Lee Ying-Shuan , Chang Jia-Ming , Huang Jiann-Jyh , Chuang Shih-Hsien , Kao Kuo-Jang , Lau Gillian M.G. , Tsai Pei-Yi , Liu Chia-Wei , Lin Her-Sheng , Lau Johnson Y.N.
Published: April 2023

Abstract
Current cytotoxic chemotherapy produces clinical benefit in patients with breast cancer but the survival impact is modest. To explore novel cytotoxic agents for the treatment of advanced disease, we have characterized a new and pharmacokinetically improved Hec1-targeted compound, TAI-95. Nine of 11 breast cancer cell lines tested were sensitive to nanomolar levels of TAI-95 (GI50 = 14.29–73.65 nmol/L), and more importantly, TAI-95 was active on a number of cell lines that were resistant (GI50 > 10 μmol/L) to other established cytotoxic agents. TAI-95 demonstrates strong inhibition of in vivo tumor growth of breast cancer model when administered orally, without inducing weight loss or other obvious toxicity. Mechanistically, TAI-95 acts by disrupting the interaction between Hec1 and Nek2, leading to apoptotic cell death in breast cancer cells. Furthermore, TAI-95 is active on multidrug-resistant (MDR) cell lines and led to downregulation of the expression of P-glycoprotein (Pgp), an MDR gene. In addition, TAI-95 increased the potency of cytotoxic Pgp substrates, including doxorubicin and topotecan. Certain clinical subtypes of breast cancer more likely to respond to Hec1-targeted therapy were identified and these subtypes are the ones associated with poor prognosis. This study highlights the potential of the novel anticancer compound TAI-95 in difficult-to-treat breast cancers. Mol Cancer Ther; 13(6); 1419–30. ©2014 AACR.
Data from The NADPH Oxidase Inhibitor Imipramine-Blue in the Treatment of Burkitt Lymphoma
Authors: Klingenberg Marcel , Becker Jürgen , Eberth Sonja , Kube Dieter , Wilting Jörg
Published: April 2023

Abstract
Burkitt lymphoma is a rare malignancy arising from B cells. Current chemotherapeutic regimens achieve excellent overall survival rates in children, but less impressive rates in adults. There are cases with poor outcome caused by toxic effects of the therapy, tumor lysis syndrome, or metastatic spread of lymphomas to the central nervous system. Modulators of reactive oxygen species are currently discussed as potential drugs for the treatment of cancer. The NADPH oxidase 4 inhibitor imipramine-blue might satisfy the aforementioned requirements, and was studied here. We used MTT assay, crystal violet assay, and thymidine 3H-incorporation assay to analyze the effects of imipramine-blue on Burkitt lymphoma (BL2, BL2B95, BL30B95, BL41B95), neuroblastoma (KELLY, SH-SY5Y, SMS-KAN), cervix carcinoma (HeLa), breast cancer (MDA-MB231), angiosarcoma (AS-M), human embryonic kidney (HEK293WT), and nonmalignant (FLP1) cell lines. The effects of imipramine-blue on BL2B95 cells in vivo were investigated in xenografts on the chick chorioallantoic membrane (CAM). We report that imipramine-blue is a potent growth inhibitor for several cancer cell lines in vitro with IC50 values comparable to those of doxorubicin (0.16–7.7 μmol/L). Tumor size of BL2B95 cells inoculated in the CAM was reduced significantly (P < 0.05) after treatment with 10 μmol/L imipramine-blue. Lymphogenic dissemination of BL2B95 and the formation of blood and lymphatic vessels in experimental tumors were not affected. We show that imipramine-blue can be used to decrease the viability of cancer cell lines in vitro and in vivo. Imipramine-blue reduces the size of experimental Burkitt lymphoma significantly but does not affect the dissemination of BL2B95 cells, angiogenesis, and lymphangiogenesis. Mol Cancer Ther; 13(4); 833–41. ©2014 AACR.
Data from Targeting STAT5 in Hematologic Malignancies through Inhibition of the Bromodomain and Extra-Terminal (BET) Bromodomain Protein BRD2
Authors: Liu Suhu , Walker Sarah R. , Nelson Erik A. , Cerulli Robert , Xiang Michael , Toniolo Patricia A. , Qi Jun , Stone Richard M. , Wadleigh Martha , Bradner James E. , Frank David A.
Published: April 2023

Abstract
The transcription factor signal STAT5 is constitutively activated in a wide range of leukemias and lymphomas, and drives the expression of genes necessary for proliferation, survival, and self-renewal. Thus, targeting STAT5 is an appealing therapeutic strategy for hematologic malignancies. Given the importance of bromodomain-containing proteins in transcriptional regulation, we considered the hypothesis that a pharmacologic bromodomain inhibitor could inhibit STAT5-dependent gene expression. We found that the small-molecule bromodomain and extra-terminal (BET) bromodomain inhibitor JQ1 decreases STAT5-dependent (but not STAT3-dependent) transcription of both heterologous reporter genes and endogenous STAT5 target genes. JQ1 reduces STAT5 function in leukemia and lymphoma cells with constitutive STAT5 activation, or inducibly activated by cytokine stimulation. Among the BET bromodomain subfamily of proteins, it seems that BRD2 is the critical mediator for STAT5 activity. In experimental models of acute T-cell lymphoblastic leukemias, where activated STAT5 contributes to leukemia cell survival, Brd2 knockdown or JQ1 treatment shows strong synergy with tyrosine kinase inhibitors (TKI) in inducing apoptosis in leukemia cells. In contrast, mononuclear cells isolated form umbilical cord blood, which is enriched in normal hematopoietic precursor cells, were unaffected by these combinations. These findings indicate a unique functional association between BRD2 and STAT5, and suggest that combinations of JQ1 and TKIs may be an important rational strategy for treating leukemias and lymphomas driven by constitutive STAT5 activation. Mol Cancer Ther; 13(5); 1194–205. ©2014 AACR.
Data from Mechanism and Efficacy of Sub–50-nm Tenfibgen Nanocapsules for Cancer Cell–Directed Delivery of Anti-CK2 RNAi to Primary and Metastatic Squamous Cell Carcinoma
Authors: Unger Gretchen M. , Kren Betsy T. , Korman Vicci L. , Kimbrough Tyler G. , Vogel Rachel I. , Ondrey Frank G. , Trembley Janeen H. , Ahmed Khalil
Published: April 2023

Abstract
Improved survival for patients with head and neck cancers (HNC) with recurrent and metastatic disease warrants that cancer therapy is specific, with protected delivery of the therapeutic agent to primary and metastatic cancer cells. A further objective should be that downregulation of the intracellular therapy target leads to cell death without compensation by an alternate pathway. To address these goals, we report the utilization of a sub–50-nm tenfibgen (s50-TBG) nanocapsule that delivers RNAi oligonucleotides directed against the essential survival signal protein kinase CK2 (RNAi-CK2) in a cancer cell–specific manner. We have evaluated mechanism and efficacy of using s50-TBG-RNAi-CK2 nanocapsules for therapy of primary and metastatic head and neck squamous cell carcinoma (HNSCC). s50-TBG nanocapsules enter cancer cells via the lipid raft/caveolar pathway and deliver their cargo (RNAi-CK2) preferentially to malignant but not normal tissues in mice. Our data suggest that RNAi-CK2, a unique single-stranded oligonucleotide, co-opts the argonaute 2/RNA-induced silencing complex pathway to target the CK2αα′ mRNAs. s50-TBG-RNAi-CK2 inhibited cell growth corresponding with reduced CK2 expression in targeted tumor cells. Treatment of three xenograft HNSCC models showed that primary tumors and metastases responded to s50-TBG-RNAi-CK2 therapy, with tumor shrinkage and 6-month host survival that was achieved at relatively low doses of the therapeutic agent without any adverse toxic effect in normal tissues in the mice. We suggest that our nanocapsule technology and anti-CK2 targeting combine into a therapeutic modality with a potential of significant translational promise. Mol Cancer Ther; 13(8); 2018–29. ©2014 AACR.
Data from Inhibition of Homologous Recombination and Promotion of Mutagenic Repair of DNA Double-Strand Breaks Underpins Arabinoside–Nucleoside Analogue Radiosensitization
Authors: Magin Simon , Papaioannou Maria , Saha Janapriya , Staudt Christian , Iliakis George
Published: April 2023

Abstract
In concurrent chemoradiotherapy, drugs are used to sensitize tumors to ionizing radiation. Although a spectrum of indications for simultaneous treatment with drugs and radiation has been defined, the molecular mechanisms underpinning tumor radiosensitization remain incompletely characterized for several such combinations. Here, we investigate the mechanisms of radiosensitization by the arabinoside nucleoside analogue 9-β-D-arabinofuranosyladenine (araA) placing particular emphasis on the repair of DNA double-strand breaks (DSB), and compare the results to those obtained with fludarabine (F-araA) and cytarabine (araC). Postirradiation treatment with araA strongly sensitizes cells to ionizing radiation, but leaves unchanged DSB repair by NHEJ in logarithmically growing cells, in sorted G1 or G2 phase populations, as well as in cells in the plateau phase of growth. Notably, araA strongly inhibits DSB repair by homologous recombination (HRR), as assessed by scoring ionizing radiation–induced RAD51 foci, and in functional assays using integrated reporter constructs. Cells compromised in HRR by RNAi-mediated transient knockdown of RAD51 show markedly reduced radiosensitization after treatment with araA. Remarkably, mutagenic DSB repair compensates for HRR inhibition in araA-treated cells. Compared with araA, F-araA and araC are only modestly radiosensitizing under the conditions examined. We propose that the radiosensitizing potential of nucleoside analogues is linked to their ability to inhibit HRR and concomitantly promote the error-prone processing of DSBs. Our observations pave the way to treatment strategies harnessing the selective inhibitory potential of nucleoside analogues and the development of novel compounds specifically utilizing HRR inhibition as a means of tumor cell radiosensitization. Mol Cancer Ther; 14(6); 1424–33. ©2015 AACR.
Data from REST Negatively and ISGF3 Positively Regulate the Human STAT1 Gene in Melanoma
Authors: Amalraj James , Cutler Samuel J. , Ghazawi Ibtisam , Boyle Glen M. , Ralph Stephen J.
Published: April 2023

Abstract
STAT1 plays a pivotal role in signal transduction and transcriptional activation in response to type I and II IFNs. Regulation of STAT1 expression has significant consequences in human cancer cells, where STAT1 deficiencies have been associated with cellular resistance to type I IFN. Distinct promoter, enhancer, and repressor regions have previously been described in the regulatory part of the human STAT1 gene extending as far as the second intron. A putative IFN-stimulated response element sequence in the STAT1 promoter is inducible by type I IFN and binds the IFN-α/β–induced complex, ISGF3. Together with the previously characterized IRF-E/GAS/IRF-E (IGI) motif, these positive regulatory elements provide a means for intracellular amplification of STAT1 expression, which is necessary for increasing cell responsiveness to the IFNs. In contrast, the transcriptional repressor REST binds to an RE-1 element in the STAT1 repressor region and in doing so represses transcription from the STAT1 gene regulatory region in melanoma cells lines. Repression significantly decreased in a REST-null cell line. Altering REST function from a transcriptional repressor into an activator as REST-VP16 increased expression from RE-1–targeted reporters. RNA expression of 65 melanoma cell lines by microarray and selected lines with known IFN responsiveness showed significant inverse correlations between STAT1/REST that were related to cellular responses to IFN. Thus REST, through the intronic RE-1 element, provides a means for downregulating STAT1 expression, affecting melanoma responsiveness to IFN. Intracellular levels of REST may be a useful marker to test for IFN resistance and as a novel therapeutic target in IFN-resistant melanomas. Mol Cancer Ther; 12(7); 1288–98. ©2013 AACR.
Data from Epithelial-to-Mesenchymal Transition Mediates Docetaxel Resistance and High Risk of Relapse in Prostate Cancer
Authors: Marín-Aguilera Mercedes , Codony-Servat Jordi , Reig Òscar , Lozano Juan José , Fernández Pedro Luis , Pereira María Verónica , Jiménez Natalia , Donovan Michael , Puig Pere , Mengual Lourdes , Bermudo Raquel , Font Albert , Gallardo Enrique , Ribal María José , Alcaraz Antonio , Gascón Pere , Mellado Begoña
Published: April 2023

Abstract
Molecular characterization of radical prostatectomy specimens after systemic therapy may identify a gene expression profile for resistance to therapy. This study assessed tumor cells from patients with prostate cancer participating in a phase II neoadjuvant docetaxel and androgen deprivation trial to identify mediators of resistance. Transcriptional level of 93 genes from a docetaxel-resistant prostate cancer cell lines microarray study was analyzed by TaqMan low-density arrays in tumors from patients with high-risk localized prostate cancer (36 surgically treated, 28 with neoadjuvant docetaxel + androgen deprivation). Gene expression was compared between groups and correlated with clinical outcome. VIM, AR and RELA were validated by immunohistochemistry. CD44 and ZEB1 expression was tested by immunofluorescence in cells and tumor samples. Parental and docetaxel-resistant castration-resistant prostate cancer cell lines were tested for epithelial-to-mesenchymal transition (EMT) markers before and after docetaxel exposure. Reversion of EMT phenotype was investigated as a docetaxel resistance reversion strategy. Expression of 63 (67.7%) genes differed between groups (P < 0.05), including genes related to androgen receptor, NF-κB transcription factor, and EMT. Increased expression of EMT markers correlated with radiologic relapse. Docetaxel-resistant cells had increased EMT and stem-like cell markers expression. ZEB1 siRNA transfection reverted docetaxel resistance and reduced CD44 expression in DU-145R and PC-3R. Before docetaxel exposure, a selected CD44+ subpopulation of PC-3 cells exhibited EMT phenotype and intrinsic docetaxel resistance; ZEB1/CD44+ subpopulations were found in tumor cell lines and primary tumors; this correlated with aggressive clinical behavior. This study identifies genes potentially related to chemotherapy resistance and supports evidence of the EMT role in docetaxel resistance and adverse clinical behavior in early prostate cancer. Mol Cancer Ther; 13(5); 1270–84. ©2014 AACR.
Data from Sarcoma Cell Line Screen of Oncology Drugs and Investigational Agents Identifies Patterns Associated with Gene and microRNA Expression
Authors: Teicher Beverly A. , Polley Eric , Kunkel Mark , Evans David , Silvers Thomas , Delosh Rene , Laudeman Julie , Ogle Chad , Reinhart Russell , Selby Michael , Connelly John , Harris Erik , Monks Anne , Morris Joel
Published: April 2023

Abstract
The diversity in sarcoma phenotype and genotype make treatment of this family of diseases exceptionally challenging. Sixty-three human adult and pediatric sarcoma lines were screened with 100 FDA-approved oncology agents and 345 investigational agents. The investigational agents' library enabled comparison of several compounds targeting the same molecular entity allowing comparison of target specificity and heterogeneity of cell line response. Gene expression was derived from exon array data and microRNA expression was derived from direct digital detection assays. The compounds were screened against each cell line at nine concentrations in triplicate with an exposure time of 96 hours using Alamar blue as the endpoint. Results are presented for inhibitors of the following targets: aurora kinase, IGF-1R, MEK, BET bromodomain, and PARP1. Chemical structures, IC50 heat maps, concentration response curves, gene expression, and miR expression heat maps are presented for selected examples. In addition, two cases of exceptional responders are presented. The drug and compound response, gene expression, and microRNA expression data are publicly available at http://sarcoma.cancer.gov. These data provide a unique resource to the cancer research community. Mol Cancer Ther; 14(11); 2452–62. ©2015 AACR.
Data from Delineating the mTOR Kinase Pathway Using a Dual TORC1/2 Inhibitor, AZD8055, in Multiple Myeloma
Authors: Cirstea Diana , Santo Loredana , Hideshima Teru , Eda Homare , Mishima Yuko , Nemani Neeharika , Mahindra Anuj , Yee Andrew , Gorgun Gullu , Hu Yiguo , Ohguchi Hiroto , Suzuki Rikio , Cottini Francesca , Guichard Sylvie M. , Anderson Kenneth C. , Raje Noopur
Published: April 2023

Abstract
Despite promising preclinical results with mTOR kinase inhibitors in multiple myeloma, resistance to these drugs may arise via feedback activation loops. This concern is especially true for insulin-like growth factor 1 receptor (IGF1R), because IGF1R signaling is downregulated by multiple AKT and mTOR feedback mechanisms. We have tested this hypothesis in multiple myeloma using the novel selective mTOR kinase inhibitor AZD8055. We evaluated p-mTOR S2481 as the readout for mTORC2/Akt activity in multiple myeloma cells in the context of mTOR inhibition via AZD8055 or rapamycin. We next validated AZD8055 inhibition of mTORC1 and mTORC2 functions in multiple myeloma cells alone or in culture with bone marrow stroma cells and growth factors. Unlike rapamycin, AZD8055 resulted in apoptosis of multiple myeloma cells. AZD8055 treatment, however, induced upregulation of IGF1R phosphorylation in p-Akt S473–expressing multiple myeloma cell lines. Furthermore, exposure of AZD8055-treated cells to IGF1 induced p-Akt S473 and rescued multiple myeloma cells from apoptosis despite mTOR kinase inhibition and TORC2/Akt blockage. The addition of blocking IGF1R antibody resulted in reversing this effect and increased AZD8055-induced apoptosis. Our study suggests that combination treatment with AZD8055 and IGF1R-blocking agents is a promising strategy in multiple myeloma with potential IGF1R/Akt signaling–mediated survival. Mol Cancer Ther; 13(11); 2489–500. ©2014 AACR.
Data from Pharmacological Profiling of Kinase Dependency in Cell Lines across Triple-Negative Breast Cancer Subtypes
Authors: Fink Lauren S. , Beatty Alexander , Devarajan Karthik , Peri Suraj , Peterson Jeffrey R.
Published: April 2023

Abstract
Triple-negative breast cancers (TNBC), negative for estrogen receptor, progesterone receptor, and ERBB2 amplification, are resistant to standard targeted therapies and exhibit a poor prognosis. Furthermore, they are highly heterogeneous with respect to genomic alterations, and common therapeutic targets are lacking though substantial evidence implicates dysregulated kinase signaling. Recently, six subtypes of TNBC were identified based on gene expression and were proposed to predict sensitivity to a variety of therapeutic agents including kinase inhibitors. To test this hypothesis, we screened a large collection of well-characterized, small molecule kinase inhibitors for growth inhibition in a panel of TNBC cell lines representing all six subtypes. Sensitivity to kinase inhibition correlated poorly with TNBC subtype. Instead, unsupervised clustering segregated TNBC cell lines according to clinically relevant features including dependence on epidermal growth factor signaling and mutation of the PTEN tumor suppressor. We further report the discovery of kinase inhibitors with selective toxicity to these groups. Overall, however, TNBC cell lines exhibited diverse sensitivity to kinase inhibition consistent with the lack of common driver mutations in this disease. Although our findings support specific kinase dependencies in subsets of TNBC, they are not associated with gene expression–based subtypes. Instead, we find that mutation status can be an effective predictor of sensitivity to inhibition of particular kinase pathways for subsets of TNBC. Mol Cancer Ther; 14(1); 298–306. ©2014 AACR.
Data from Selective Nuclear Export Inhibitor KPT-330 Enhances the Antitumor Activity of Gemcitabine in Human Pancreatic Cancer
Authors: Kazim Sabiha , Malafa Mokenge P. , Coppola Domenico , Husain Kazim , Zibadi Sherma , Kashyap Trinayan , Crochiere Marsha , Landesman Yosef , Rashal Tami , Sullivan Daniel M. , Mahipal Amit
Published: April 2023

Abstract
Pancreatic cancer is an aggressive and deadly malignancy responsible for the death of over 37,000 Americans each year. Gemcitabine-based therapy is the standard treatment for pancreatic cancer but has limited efficacy due to chemoresistance. In this study, we evaluated the in vitro and in vivo effects of gemcitabine combined with the selective nuclear export (CRM1) inhibitor KPT-330 on pancreatic cancer growth. Human pancreatic cancer MiaPaCa-2 and metastatic pancreatic cancer L3.6pl cell lines were treated with different concentrations of KPT-330 and gemcitabine alone or in combination, and anchorage–dependent/independent growth was recorded. In addition, L3.6pl cells with luciferase were injected orthotopically into the pancreas of athymic nude mice, which were treated with (i) vehicle (PBS 1 mL/kg i.p., 2/week and povidone/pluronic F68 1 mL/kg p.o., 3/week), (ii) KPT-330 (20 mg/kg p.o., 3/week), (iii) gemcitabine (100 mg/kg i.p., 2/week), or (iv) KPT-330 (10 mg/kg) + gemcitabine (50 mg/kg) for 4 weeks. KPT-330 and gemcitabine alone dose-dependently inhibited anchorage-dependent growth in vitro and tumor volume in vivo compared with vehicle treatment. However, the combination inhibited growth synergistically. In combination, KPT-330 and gemcitabine acted synergistically to enhance pancreatic cancer cell death greater than each single-agent therapy. Mechanistically, KPT-330 and gemcitabine promoted apoptosis, induced p27, depleted survivin, and inhibited accumulation of DNA repair proteins. Together, our data suggest that KPT-330 potentiates the antitumor activity of gemcitabine in human pancreatic cancer through inhibition of tumor growth, depletion of the antiapoptotic proteins, and induction of apoptosis. Mol Cancer Ther; 14(7); 1570–81. ©2015 AACR.
Data from Effective Inhibition of Bone Morphogenetic Protein Function by Highly Specific Llama-Derived Antibodies
Authors: Calpe Silvia , Wagner Koen , El Khattabi Mohamed , Rutten Lucy , Zimberlin Cheryl , Dolk Edward , Verrips C. Theo , Medema Jan Paul , Spits Hergen , Krishnadath Kausilia K.
Published: April 2023

Abstract
Bone morphogenetic proteins (BMP) have important but distinct roles in tissue homeostasis and disease, including carcinogenesis and tumor progression. A large number of BMP inhibitors are available to study BMP function; however, as most of these antagonists are promiscuous, evaluating specific effects of individual BMPs is not feasible. Because the oncogenic role of the different BMPs varies for each neoplasm, highly selective BMP inhibitors are required. Here, we describe the generation of three types of llama-derived heavy chain variable domains (VHH) that selectively bind to either BMP4, to BMP2 and 4, or to BMP2, 4, 5, and 6. These generated VHHs have high affinity to their targets and are able to inhibit BMP signaling. Epitope binning and docking modeling have shed light into the basis for their BMP specificity. As opposed to the wide structural reach of natural inhibitors, these small molecules target the grooves and pockets of BMPs involved in receptor binding. In organoid experiments, specific inhibition of BMP4 does not affect the activation of normal stem cells. Furthermore, in vitro inhibition of cancer-derived BMP4 noncanonical signals results in an increase of chemosensitivity in a colorectal cancer cell line. Therefore, because of their high specificity and low off-target effects, these VHHs could represent a therapeutic alternative for BMP4+ malignancies. Mol Cancer Ther; 14(11); 2527–40. ©2015 AACR.
Data from Polymorphisms in Genes Involved in EGFR Turnover Are Predictive for Cetuximab Efficacy in Colorectal Cancer
Authors: Stintzing Sebastian , Zhang Wu , Heinemann Volker , Neureiter Daniel , Kemmerling Ralf , Kirchner Thomas , Jung Andreas , Folwaczny Matthias , Yang Dongyun , Ning Yan , Sebio Ana , Stremitzer Stefan , Sunakawa Yu , Matsusaka Satoshi , Yamauchi Shinichi , Loupakis Fotios , Cremolini Chiara , Falcone Alfredo , Lenz Heinz-Josef
Published: April 2023

Abstract
Transmembrane receptors, such as the EGFR, are regulated by their turnover, which is dependent on the ubiquitin-proteasome system. We tested in two independent study cohorts whether SNPs in genes involved in EGFR turnover predict clinical outcome in cetuximab-treated metastatic colorectal cancer (mCRC) patients. The following SNPs involved in EGFR degradation were analyzed in a screening cohort of 108 patients treated with cetuximab in the chemorefractory setting: c-CBL (rs7105971; rs4938637; rs4938638; rs251837), EPS15 (rs17567; rs7308; rs1065754), NAE1 (rs363169; rs363170; rs363172), SH3KBP1 (rs7051590; rs5955820; rs1017874; rs11795873), SGIP1 (rs604737; rs6570808; rs7526812), UBE2M (rs895364; rs895374), and UBE2L3 (rs5754216). SNPs showing an association with response or survival were analyzed in BRAF and RAS wild-type samples from the FIRE-3 study. One hundred and fifty-three FOLFIRI plus cetuximab-treated patients served as validation set, and 168 patients of the FOLFIRI plus bevacizumab arm served as controls. EGFR FISH was done in 138 samples to test whether significant SNPs were associated with EGFR expression. UBE2M rs895374 was significantly associated with progression-free survival (log-rank P = 0.005; HR, 0.60) within cetuximab-treated patients. No association with bevacizumab-treated patients (n = 168) could be established (P = 0.56; HR, 0.90). rs895374 genotype did not affect EGFR FISH measurements. EGFR recycling is an interesting mechanism of secondary resistance to cetuximab in mCRC. This is the first report suggesting that germline polymorphisms in the degradation process predict efficacy of cetuximab in patients with mCRC. Genes involved in EGFR turnover may be new targets in the treatment of mCRC. Mol Cancer Ther; 14(10); 2374–81. ©2015 AACR.
Data from Elevated LIM Kinase 1 in Nonmetastatic Prostate Cancer Reflects Its Role in Facilitating Androgen Receptor Nuclear Translocation
Authors: Mardilovich Katerina , Gabrielsen Mads , McGarry Lynn , Orange Clare , Patel Rachana , Shanks Emma , Edwards Joanne , Olson Michael F.
Published: April 2023

Abstract
Prostate cancer affects a large proportion of the male population, and is primarily driven by androgen receptor (AR) activity. First-line treatment typically consists of reducing AR signaling by hormone depletion, but resistance inevitably develops over time. One way to overcome this issue is to block AR function via alternative means, preferably by inhibiting protein targets that are more active in tumors than in normal tissue. By staining prostate cancer tumor sections, elevated LIM kinase 1 (LIMK1) expression and increased phosphorylation of its substrate Cofilin were found to be associated with poor outcome and reduced survival in patients with nonmetastatic prostate cancer. A LIMK-selective small molecule inhibitor (LIMKi) was used to determine whether targeted LIMK inhibition was a potential prostate cancer therapy. LIMKi reduced prostate cancer cell motility, as well as inhibiting proliferation and increasing apoptosis in androgen-dependent prostate cancer cells more effectively than in androgen-independent prostate cancer cells. LIMK inhibition blocked ligand-induced AR nuclear translocation, reduced AR protein stability and transcriptional activity, consistent with its effects on proliferation and survival acting via inhibition of AR activity. Furthermore, inhibition of LIMK activity increased αTubulin acetylation and decreased AR interactions with αTubulin, indicating that the role of LIMK in regulating microtubule dynamics contributes to AR function. These results indicate that LIMK inhibitors could be beneficial for the treatment of prostate cancer both by reducing nuclear AR translocation, leading to reduced proliferation and survival, and by inhibiting prostate cancer cell dissemination. Mol Cancer Ther; 14(1); 246–58. ©2014 AACR.
Data from Identification of Kinase Inhibitor Targets in the Lung Cancer Microenvironment by Chemical and Phosphoproteomics
Authors: Gridling Manuela , Ficarro Scott B. , Breitwieser Florian P. , Song Lanxi , Parapatics Katja , Colinge Jacques , Haura Eric B. , Marto Jarrod A. , Superti-Furga Giulio , Bennett Keiryn L. , Rix Uwe
Published: April 2023

Abstract
A growing number of gene mutations, which are recognized as cancer drivers, can be successfully targeted with drugs. The redundant and dynamic nature of oncogenic signaling networks and complex interactions between cancer cells and the microenvironment, however, can cause drug resistance. While these challenges can be addressed by developing drug combinations or polypharmacology drugs, this benefits greatly from a detailed understanding of the proteome-wide target profiles. Using mass spectrometry-based chemical proteomics, we report the comprehensive characterization of the drug–protein interaction networks for the multikinase inhibitors dasatinib and sunitinib in primary lung cancer tissue specimens derived from patients. We observed in excess of 100 protein kinase targets plus various protein complexes involving, for instance, AMPK, TBK1 (sunitinib), and ILK (dasatinib). Importantly, comparison with lung cancer cell lines and mouse xenografts thereof showed that most targets were shared between cell lines and tissues. Several targets, however, were only present in tumor tissues. In xenografts, most of these proteins were of mouse origin suggesting that they originate from the tumor microenvironment. Furthermore, intersection with subsequent global phosphoproteomic analysis identified several activated signaling pathways. These included MAPK, immune, and integrin signaling, which were affected by these drugs in both cancer cells and the microenvironment. Thus, the combination of chemical and phosphoproteomics can generate a systems view of proteins, complexes, and signaling pathways that are simultaneously engaged by multitargeted drugs in cancer cells and the tumor microenvironment. This may allow for the design of novel anticancer therapies that concurrently target multiple tumor compartments. Mol Cancer Ther; 13(11); 2751–62. ©2014 AACR.
Data from BRAF Inhibition Decreases Cellular Glucose Uptake in Melanoma in Association with Reduction in Cell Volume
Authors: Theodosakis Nicholas , Held Matthew A. , Marzuka-Alcala Alexander , Meeth Katrina M. , Micevic Goran , Long Georgina V. , Scolyer Richard A. , Stern David F. , Bosenberg Marcus W.
Published: April 2023

Abstract
BRAF kinase inhibitors have dramatically affected treatment of BRAFV600E/K-driven metastatic melanoma. Early responses assessed using [18F]fluorodeoxyglucose uptake-positron emission tomography (FDG-PET) have shown dramatic reduction of radiotracer signal within 2 weeks of treatment. Despite high response rates, relapse occurs in nearly all cases, frequently at sites of treated metastatic disease. It remains unclear whether initial loss of 18FDG uptake is due to tumor cell death or other reasons. Here, we provide evidence of melanoma cell volume reduction in a patient cohort treated with BRAF inhibitors. We present data demonstrating that BRAF inhibition reduces melanoma glucose uptake per cell, but that this change is no longer significant following normalization for cell volume changes. We also demonstrate that volume normalization greatly reduces differences in transmembrane glucose transport and hexokinase-mediated phosphorylation. Mechanistic studies suggest that this loss of cell volume is due in large part to decreases in new protein translation as a consequence of vemurafenib treatment. Ultimately, our findings suggest that cell volume regulation constitutes an important physiologic parameter that may significantly contribute to radiographic changes observed in clinic. Mol Cancer Ther; 14(7); 1680–92. ©2015 AACR.
Data from Targeting Ribonucleotide Reductase M2 and NF-κB Activation with Didox to Circumvent Tamoxifen Resistance in Breast Cancer
Authors: Shah Khyati N. , Wilson Elizabeth A. , Malla Ritu , Elford Howard L. , Faridi Jesika S.
Published: April 2023

Abstract
Tamoxifen is widely used as an adjuvant therapy for patients with estrogen receptor (ERα)–positive tumors. However, the clinical benefit is often limited because of the emergence of drug resistance. In this study, overexpression of ribonucleotide reductase M2 (RRM2) in MCF-7 breast cancer cells resulted in a reduction in the effectiveness of tamoxifen, through downregulation of ERα66 and upregulation of the 36-kDa variant of ER (ERα36). We identified that NF-κB, HIF1α, and MAPK/JNK are the major pathways that are affected by RRM2 overexpression and result in increased NF-κB activity and increased protein levels of EGFR, HER2, IKKs, Bcl-2, RelB, and p50. RRM2-overexpressing cells also exhibited higher migratory and invasive properties. Through time-lapse microscopy and protein profiling studies of tamoxifen-treated MCF-7 and T-47D cells, we have identified that RRM2, along with other key proteins, is altered during the emergence of acquired tamoxifen resistance. Inhibition of RRM2 using siRRM2 or the ribonucleotide reductase (RR) inhibitor didox not only eradicated and effectively prevented the emergence of tamoxifen-resistant populations but also led to the reversal of many of the proteins altered during the process of acquired tamoxifen resistance. Because didox also appears to be a potent inhibitor of NF-κB activation, combining didox with tamoxifen treatment cooperatively reverses ER-α alterations and inhibits NF-κB activation. Finally, inhibition of RRM2 by didox reversed tamoxifen-resistant in vivo tumor growth and decreased in vitro migratory and invasive properties, revealing a beneficial effect of combination therapy that includes RRM2 inhibition to delay or abrogate tamoxifen resistance. Mol Cancer Ther; 14(11); 2411–21. ©2015 AACR.
Data from Targeted Silencing of MLL5β Inhibits Tumor Growth and Promotes Gamma-Irradiation Sensitization in HPV16/18-Associated Cervical Cancers
Authors: Nin Dawn Sijin , Yew Chow Wenn , Tay Sun Kuie , Deng Lih-Wen
Published: April 2023

Abstract
We previously identified a novel MLL5 isoform, MLL5β, which was essential for E6 and E7 transcriptional activation in HPV16/18-associated cervical cancers. In this report, we investigated the potential of RNAi-mediated silencing of MLL5β through the use of MLL5β-siRNA as a novel therapeutic strategy for HPV16/18-positive cervical cancer. We observed concurrent downregulation of E6 and E7 after MLL5β silencing, leading to growth inhibition via the activation of apoptosis and senescence in the HeLa cell model. This corresponded with the enhanced antitumor effects of MLL5β-siRNA compared with E6- or E7-siRNA single treatments. Significant reduction in tumor size after MLLβ-siRNA treatment in the HeLa xenograft tumor model further emphasized the importance of MLL5β in HPV16/18-associated tumor growth and the potential of RNAi therapeutics that target MLL5β. We also identified MLL5β as a modulator of gamma-irradiation (IR) sensitization properties of cisplatin. We observed that while MLL5β silencing alone was enough to evoke cisplatin-like IR sensitization in tumor cells in vitro, overexpression of MLL5β inhibited the ability of cisplatin to sensitize HeLa cells to IR-induced cytotoxicity. MLL5β-siRNA-IR cotreatment was also observed to enhance tumor growth inhibition in vivo. Taken together, our findings highlight the potential of targeted silencing of MLL5β via the use of MLL5β-siRNA as a novel therapeutic strategy and propose that MLL5β-siRNA could be a viable alternative for cisplatin in the current cisplatin-based chemotherapeutics for HPV16/18-associated cervical cancers. Mol Cancer Ther; 13(11); 2572–82. ©2014 AACR.
Data from A Comprehensive Evaluation of Biomarkers Predictive of Response to PI3K Inhibitors and of Resistance Mechanisms in Head and Neck Squamous Cell Carcinoma
Authors: Mazumdar Tuhina , Byers Lauren A. , Ng Patrick Kwok Shing , Mills Gordon B. , Peng Shaohua , Diao Lixia , Fan You-Hong , Stemke-Hale Katherine , Heymach John V. , Myers Jeffrey N. , Glisson Bonnie S. , Johnson Faye M.
Published: April 2023

Abstract
The PI3K/AKT/mTOR pathway is frequently activated in head and neck squamous cell carcinoma (HNSCC), but pathway inhibition has variable efficacy. Identification of predictive biomarkers and mechanisms of resistance would allow selection of patients most likely to respond and novel therapeutic combinations. The purpose of this study was to extend recent discoveries regarding the PI3K/AKT/mTOR pathway in HNSCC by more broadly examining potential biomarkers of response, by examining pathway inhibitors with a diverse range of targets, and by defining mechanisms of resistance and potential combination therapies. We used reverse-phase protein arrays (RPPA) to simultaneously evaluate expression of 195 proteins; SNP array to estimate gene copy number; and mass array to identify mutations. We examined altered signaling at baseline and after pathway inhibition. Likewise, we examined the activation of the PI3K/AKT/mTOR pathway in HNSCC tumors by RPPA. Cell lines with PIK3CA mutations were sensitive to pathway inhibitors, whereas amplification status did not predict sensitivity. While we identified a set of individual candidate biomarkers of response to pathway inhibitors, proteomic pathway scores did not correlate with amplification or mutation and did not predict response. Several receptor tyrosine kinases, including EGFR and ERK, were activated following PI3K inhibition in resistant cells; dual pathway inhibition of PI3K and EGFR or MEK demonstrated synergy. Combined MEK and PI3K inhibition was markedly synergistic in HRAS-mutant cell lines. Our findings indicate that clinical trials of single-agent PI3K/AKT/mTOR pathway inhibitors in selected populations and of PI3K/EGFR or PI3K/MEK inhibitor combinations are warranted; we plan to conduct such trials. Mol Cancer Ther; 13(11); 2738–50. ©2014 AACR.
Data from Improved Circulating Tumor Cell Detection by a Combined EpCAM and MCAM CellSearch Enrichment Approach in Patients with Breast Cancer Undergoing Neoadjuvant Chemotherapy
Authors: Onstenk Wendy , Kraan Jaco , Mostert Bianca , Timmermans Mieke M. , Charehbili Ayoub , Smit Vincent T.H.B.M. , Kroep Judith R. , Nortier Johan W.R. , van de Ven Saskia , Heijns Joan B. , Kessels Lonneke W. , van Laarhoven Hanneke W.M. , Bos Monique M.E.M. , van de Velde Cornelis J.H. , Gratama Jan W. , Sieuwerts Anieta M. , Martens John W.M. , Foekens John A. , Sleijfer Stefan
Published: April 2023

Abstract
Circulating tumor cells (CTC) are detected by the CellSearch System in 20% to 25% of patients with primary breast cancer (pBC). To improve CTC detection, we investigated melanoma cell adhesion molecule (MCAM) as enrichment marker next to epithelial cell adhesion molecule (EpCAM) and tested the clinical relevance of MCAM-positive CTCs in patients with HER2-negative stage II/III pBC starting neoadjuvant chemotherapy (NAC) in the NEOZOTAC trial. Using the CellSearch System, EpCAM-positive and MCAM-positive CTCs were separately enriched from 7.5 mL blood, at baseline and after the first NAC cycle. Circulating endothelial cells (CEC) were measured using flow cytometry. Primary objective was to improve the CTC detection rate to ≥40% combining EpCAM/MCAM. Correlations of CTC and CEC counts and pathologic complete response (pCR) were also explored. At baseline, we detected EpCAM-positive and MCAM-positive CTCs in 12 of 68 (18%) and 8 of 68 (12%) patients, respectively. After one cycle, this was 7 of 44 (16%) and 7 of 44 (16%) patients, respectively. The detection rate improved from 18% at baseline and 16% after one cycle with EpCAM to 25% (P = 0.08) and 30% (P = 0.02), respectively, with EpCAM/MCAM. No patients with MCAM-positive CTCs versus 23% of patients without MCAM-positive CTCs at baseline achieved pCR (P = 0.13). EpCAM-positive CTCs and CEC counts were not correlated to pCR. Combined EpCAM/MCAM CellSearch enrichment thus increased the CTC detection rate in stage II/III pBC. We found no associations of CTC and CEC counts with pCR to NAC. The clinical relevance of MCAM-positive CTCs deserves further study. Mol Cancer Ther; 14(3); 821–7. ©2014 AACR.
Data from Synergistic Simvastatin and Metformin Combination Chemotherapy for Osseous Metastatic Castration-Resistant Prostate Cancer
Authors: Babcook Melissa A. , Shukla Sanjeev , Fu Pingfu , Vazquez Edwin J. , Puchowicz Michelle A. , Molter Joseph P. , Oak Christine Z. , MacLennan Gregory T. , Flask Chris A. , Lindner Daniel J. , Parker Yvonne , Daneshgari Firouz , Gupta Sanjay
Published: April 2023

Abstract
Docetaxel chemotherapy remains a standard of care for metastatic castration-resistant prostate cancer (CRPC). Docetaxel modestly increases survival, yet results in frequent occurrence of side effects and resistant disease. An alternate chemotherapy with greater efficacy and minimal side effects is needed. Acquisition of metabolic aberrations promoting increased survival and metastasis in CRPC cells includes constitutive activation of Akt, loss of adenosine monophosphate-activated protein kinase (AMPK) activity due to Ser-485/491 phosphorylation, and overexpression of 3-hydroxy-3-methylglutaryl–Coenzyme A reductase (HMG-CoAR). We report that combination of simvastatin and metformin, within pharmacologic dose range (500 nmol/L to 4 μmol/L simvastatin and 250 μmol/L to 2 mmol/L metformin), significantly and synergistically reduces C4-2B3/B4 CRPC cell viability and metastatic properties, with minimal adverse effects on normal prostate epithelial cells. Combination of simvastatin and metformin decreased Akt Ser-473 and Thr-308 phosphorylation and AMPKα Ser-485/491 phosphorylation; increased Thr-172 phosphorylation and AMPKα activity, as assessed by increased Ser-79 and Ser-872 phosphorylation of acetyl-CoA carboxylase and HMG-CoAR, respectively; decreased HMG-CoAR activity; and reduced total cellular cholesterol and its synthesis in both cell lines. Studies of C4-2B4 orthotopic NCr-nu/nu mice further demonstrated that combination of simvastatin and metformin (3.5–7.0 μg/g body weight simvastatin and 175–350 μg/g body weight metformin) daily by oral gavage over a 9-week period significantly inhibited primary ventral prostate tumor formation, cachexia, bone metastasis, and biochemical failure more effectively than 24 μg/g body weight docetaxel intraperitoneally injected every 3 weeks, 7.0 μg/g/day simvastatin, or 350 μg/g/day metformin treatment alone, with significantly less toxicity and mortality than docetaxel, establishing combination of simvastatin and metformin as a promising chemotherapeutic alternative for metastatic CRPC. Mol Cancer Ther; 13(10); 2288–302. ©2014 AACR.
Data from Hsp27 Inhibition with OGX-427 Sensitizes Non–Small Cell Lung Cancer Cells to Erlotinib and Chemotherapy
Authors: Lelj-Garolla Barbara , Kumano Masafumi , Beraldi Eliana , Nappi Lucia , Rocchi Palma , Ionescu Diana N. , Fazli Ladan , Zoubeidi Amina , Gleave Martin E.
Published: April 2023

Abstract
Non–small cell lung cancer (NSCLC) is the most frequent cause of death from cancer worldwide. Despite the availability of active chemotherapy regimens and EGFR tyrosine kinase inhibitors, all advanced patients develop recurrent disease after first-line therapy. Although Hsp27 is a stress-induced chaperone that promotes acquired resistance in several cancers, its relationship to treatment resistance in NSCLC has not been defined. Understanding adaptive responses of acquired resistance will help guide new strategies to control NSCLC. Hsp27 levels were evaluated in an HCC827 erlotinib-resistant–derived cell line (HCC-827Resistant), and sensitivity to erlotinib was examined in Hsp27-overexpressing A549 cells. The role of Hsp27 in both erlotinib and cytotoxic treatment resistance was evaluated in HCC-827 and A549 NSCLC cells using the Hsp27 antisense drug OGX-427. The effect of OGX-427 in combination with erlotinib was also assessed in mice bearing A549 xenografts. Hsp27 is induced by erlotinib and protects NSCLC cells from treatment-induced apoptosis, whereas OGX-427 sensitizes NSCLC cells to erlotinib. Interestingly, increased resistance to erlotinib was observed when Hsp27 was increased either in HCC827 erlotinib-resistant or overexpressing A549 cells. Combining OGX-427 with erlotinib significantly enhanced antitumor effects in vitro and delayed A549 xenograft growth in vivo. OGX-427 also significantly enhanced the activity of cytotoxic drugs used for NSCLC. These data indicate that treatment-induced Hsp27 contributes to the development of resistance, and provides preclinical proof-of-principle that inhibition of stress adaptive pathways mediated by Hsp27 enhances the activity of erlotinib and chemotherapeutics. Mol Cancer Ther; 14(5); 1107–16. ©2015 AACR.