bluuebunny/crossref_metadata_2025 huggingface dataset:
Data from Imatinib Radiosensitizes Bladder Cancer by Targeting Homologous Recombination
Authors: Qiao Boling , Kerr Martin , Groselj Blaz , Teo Mark T.W. , Knowles Margaret A. , Bristow Robert G. , Phillips Roger M. , Kiltie Anne E.
Published: March 2024

Abstract
Radiotherapy is a major treatment modality used to treat muscle-invasive bladder cancer, with patient outcomes similar to surgery. However, radioresistance is a significant factor in treatment failure. Cell-free extracts of muscle-invasive bladder tumors are defective in nonhomologous end-joining (NHEJ), and this phenotype may be used clinically by combining radiotherapy with a radiosensitizing drug that targets homologous recombination, thereby sparing normal tissues with intact NHEJ. The response of the homologous recombination protein RAD51 to radiation is inhibited by the small-molecule tyrosine kinase inhibitor imatinib. Stable RT112 bladder cancer Ku knockdown (Ku80KD) cells were generated using short hairpin RNA technology to mimic the invasive tumor phenotype and also RAD51 knockdown (RAD51KD) cells to show imatinib's pathway selectivity. Ku80KD, RAD51KD, nonsilencing vector control, and parental RT112 cells were treated with radiation in combination with either imatinib or lapatinib, which inhibits NHEJ and cell survival assessed by clonogenic assay. Drug doses were chosen at approximately IC40 and IC10 (nontoxic) levels. Imatinib radiosensitized Ku80KD cells to a greater extent than RAD51KD or RT112 cells. In contrast, lapatinib radiosensitized RAD51KD and RT112 cells but not Ku80KD cells. Taken together, our findings suggest a new application for imatinib in concurrent use with radiotherapy to treat muscle-invasive bladder cancer. Cancer Res; 73(5); 1611–20. ©2012 AACR.
Data from RNA Trafficking by Acute Myelogenous Leukemia Exosomes
Authors: Huan Jianya , Hornick Noah I. , Shurtleff Matthew J. , Skinner Amy M. , Goloviznina Natalya A. , Roberts Charles T. , Kurre Peter
Published: March 2024

Abstract
Extrinsic signaling cues in the microenvironment of acute myelogenous leukemia (AML) contribute to disease progression and therapy resistance. Yet, it remains unknown how the bone marrow niche in which AML arises is subverted to support leukemic persistence at the expense of homeostatic function. Exosomes are cell membrane–derived vesicles carrying protein and RNA cargoes that have emerged as mediators of cell–cell communication. In this study, we examined the role of exosomes in developing the AML niche of the bone marrow microenvironment, investigating their biogenesis with a focus on RNA trafficking. We found that both primary AML and AML cell lines released exosome-sized vesicles that entered bystander cells. These exosomes were enriched for several coding and noncoding RNAs relevant to AML pathogenesis. Furthermore, their uptake by bone marrow stromal cells altered their secretion of growth factors. Proof-of-concept studies provided additional evidence for the canonical functions of the transferred RNA. Taken together, our findings revealed that AML exosome trafficking alters the proliferative, angiogenic, and migratory responses of cocultured stromal and hematopoietic progenitor cell lines, helping explain how the microenvironmental niche becomes reprogrammed during invasion of the bone marrow by AML. Cancer Res; 73(2); 918–29. ©2012 AACR.
Data from Earlier Detection of Breast Cancer with Ultrasound Molecular Imaging in a Transgenic Mouse Model
Authors: Bachawal Sunitha V. , Jensen Kristin C. , Lutz Amelie M. , Gambhir Sanjiv S. , Tranquart Francois , Tian Lu , Willmann Jürgen K.
Published: March 2024

Abstract
While there is an increasing role of ultrasound for breast cancer screening in patients with dense breast, conventional anatomical ultrasound lacks sensitivity and specificity for early breast cancer detection. In this study, we assessed the potential of ultrasound molecular imaging using clinically translatable vascular endothelial growth factor receptor type 2 (VEGFR2)-targeted microbubbles (MBVEGFR2) to improve the diagnostic accuracy of ultrasound in earlier detection of breast cancer and ductal carcinoma in situ (DCIS) in a transgenic mouse model [FVB/N-Tg(MMTV-PyMT)634Mul]. In vivo binding specificity studies (n = 26 tumors) showed that ultrasound imaging signal was significantly higher (P < 0.001) using MBVEGFR2 than nontargeted microbubbles and imaging signal significantly decreased (P < 0.001) by blocking antibodies. Ultrasound molecular imaging signal significantly increased (P < 0.001) when breast tissue (n = 315 glands) progressed from normal [1.65 ± 0.17 arbitrary units (a.u.)] to hyperplasia (4.21 ± 1.16), DCIS (15.95 ± 1.31), and invasive cancer (78.1 ± 6.31) and highly correlated with ex vivo VEGFR2 expression [R2 = 0.84; 95% confidence interval (CI), 0.72–0.91; P < 0.001]. At an imaging signal threshold of 4.6 a.u., ultrasound molecular imaging differentiated benign from malignant entities with a sensitivity of 84% (95% CI, 78–88) and specificity of 89% (95% CI, 81–94). In a prospective screening trail (n = 63 glands), diagnostic performance of detecting DCIS and breast cancer was assessed and two independent readers correctly diagnosed malignant disease in more than 95% of cases and highly agreed between each other [intraclass correlation coefficient (ICC) = 0.98; 95% CI, 97–99]. These results suggest that VEGFR2-targeted ultrasound molecular imaging allows highly accurate detection of DCIS and breast cancer in transgenic mice and may be a promising approach for early breast cancer detection in women. Cancer Res; 73(6); 1689–98. ©2012 AACR.
Data from Metalloprotease-Mediated Tumor Cell Shedding of B7-H6, the Ligand of the Natural Killer Cell–Activating Receptor NKp30
Authors: Schlecker Eva , Fiegler Nathalie , Arnold Annette , Altevogt Peter , Rose-John Stefan , Moldenhauer Gerhard , Sucker Antje , Paschen Annette , von Strandmann Elke Pogge , Textor Sonja , Cerwenka Adelheid
Published: March 2024

Abstract
Natural killer (NK) cells are potent immune effector cells capable of mediating antitumor responses. Thus, during immunoediting, tumor cell populations evolve strategies to escape NK-cell–mediated recognition. In this study, we report a novel mechanism of immune escape involving tumor cell shedding of B7-H6, a ligand for the activating receptor NKp30 that mediates NK-cell binding and NK-cell–mediated killing. Tumor cells from different cancer entities released B7-H6 by ectodomain shedding mediated by the cell surface proteases “a disintegrin and metalloproteases” (ADAM)-10 and ADAM-17, as demonstrated through the use of pharmacologic inhibitors or siRNA-mediated gene attenuation. Inhibiting this proteolytic shedding process increased the levels of B7-H6 expressed on the surface of tumor cells, enhancing NKp30-mediated activation of NK cells. Notably, we documented elevated levels of soluble B7-H6 levels in blood sera obtained from a subset of patients with malignant melanoma, compared with healthy control individuals, along with evidence of elevated B7-H6 expression in melanoma specimens in situ. Taken together, our results illustrated a novel mechanism of immune escape in which tumor cells impede NK-mediated recognition by metalloprotease-mediated shedding of B7-H6. One implication of our findings is that therapeutic inhibition of specific metalloproteases may help support NK-cell–based cancer therapy. Cancer Res; 74(13); 3429–40. ©2014 AACR.
Data from 14-3-3ζ Orchestrates Mammary Tumor Onset and Progression via miR-221–Mediated Cell Proliferation
Authors: Rehman Sumaiyah K. , Li Shau-Hsuan , Wyszomierski Shannon L. , Wang Qingfei , Li Ping , Sahin Ozgur , Xiao Yi , Zhang Siyuan , Xiong Yan , Yang Jun , Wang Hai , Guo Hua , Zhang Jitao D. , Medina Daniel , Muller William J. , Yu Dihua
Published: March 2024

Abstract
14-3-3ζ is overexpressed in more than 40% of breast cancers, but its pathophysiologic relevance to tumorigenesis has not been established. Here, we show that 14-3-3ζ overexpression is sufficient to induce tumorigenesis in a transgenic mouse model of breast cancer. MMTV-LTR promoter-driven HA-14-3-3ζ transgenic mice (MMTV-HA-14-3-3ζ) developed mammary tumors, whereas control mice did not. Whey acidic protein promoter-driven HA-14-3-3ζ transgenic mice (WAP-HA-14-3-3ζ) developed hyperplastic lesions and showed increased susceptibility to carcinogen-induced tumorigenesis. When crossed with MMTV-neu transgenic mice, 14-3-3ζ.neu transgenic mice exhibited accelerated mammary tumorigenesis and metastasis compared with MMTV-neu mice. Mechanistically, 14-3-3ζ overexpression enhanced MAPK/c-Jun signaling, leading to increased miR-221 transcription, which inhibited p27 CDKI translation and, consequently, promoted cell proliferation. Importantly, this 14-3-3ζ–miR-221–p27 proliferation axis is also functioning in breast tumors in patients and is associated with high-grade cancers. Taken together, our findings show that overexpression of 14-3-3ζ has a causal role in mammary tumorigenesis and progression, acting through miR-221 in cooperation with known oncogenic events to drive neoplastic cell proliferation. Cancer Res; 74(1); 363–73. ©2013 AACR.
Data from MAPK Kinase 3 Is a Tumor Suppressor with Reduced Copy Number in Breast Cancer
Authors: MacNeil Adam J. , Jiao Shun-Chang , McEachern Lori A. , Yang Yong Jun , Dennis Amanda , Yu Haiming , Xu Zhaolin , Marshall Jean S. , Lin Tong-Jun
Published: March 2024

Abstract
Cancers are initiated as a result of changes that occur in the genome. Identification of gains and losses in the structure and expression of tumor-suppressor genes and oncogenes lies at the root of the understanding of cancer cell biology. Here, we show that the mitogen–activated protein kinase (MAPK) MKK3 suppresses the growth of breast cancer, in which it varies in copy number. A pervasive loss of MKK3 gene copy number in patients with breast cancer is associated with an impairment of MKK3 expression and protein level in malignant tissues. To assess the functional role of MKK3 in breast cancer, we showed in an animal model that MKK3 activity is required for suppression of tumor growth. Active MKK3 enhanced expression of the cyclin-dependent kinase inhibitors p21Cip1/Waf1 and p27Kip1, leading to increased cell-cycle arrest in G1 phase of the cell cycle. Our results reveal the functional significance of MKK3 as a tumor suppressor and improve understanding of the dynamic role of the MAPK pathway in tumor progression. Cancer Res; 74(1); 162–72. ©2013 AACR.
Data from A DNA Methylation Prognostic Signature of Glioblastoma: Identification of NPTX2-PTEN-NF-κB Nexus
Authors: Shukla Sudhanshu , Pia Patric Irene Rosita , Thinagararjan Sivaarumugam , Srinivasan Sujaya , Mondal Baisakhi , Hegde Alangar S. , Chandramouli Bangalore A. , Santosh Vani , Arivazhagan Arimappamagan , Somasundaram Kumaravel
Published: March 2024

Abstract
Glioblastoma (GBM) is the most common, malignant adult primary tumor with dismal patient survival, yet the molecular determinants of patient survival are poorly characterized. Global methylation profile of GBM samples (our cohort; n = 44) using high-resolution methylation microarrays was carried out. Cox regression analysis identified a 9-gene methylation signature that predicted survival in GBM patients. A risk-score derived from methylation signature predicted survival in univariate analysis in our and The Cancer Genome Atlas (TCGA) cohort. Multivariate analysis identified methylation risk score as an independent survival predictor in TCGA cohort. Methylation risk score stratified the patients into low-risk and high-risk groups with significant survival difference. Network analysis revealed an activated NF-κB pathway association with high-risk group. NF-κB inhibition reversed glioma chemoresistance, and RNA interference studies identified interleukin-6 and intercellular adhesion molecule-1 as key NF-κB targets in imparting chemoresistance. Promoter hypermethylation of neuronal pentraxin II (NPTX2), a risky methylated gene, was confirmed by bisulfite sequencing in GBMs. GBMs and glioma cell lines had low levels of NPTX2 transcripts, which could be reversed upon methylation inhibitor treatment. NPTX2 overexpression induced apoptosis, inhibited proliferation and anchorage-independent growth, and rendered glioma cells chemosensitive. Furthermore, NPTX2 repressed NF-κB activity by inhibiting AKT through a p53-PTEN-dependent pathway, thus explaining the hypermethylation and downregulation of NPTX2 in NF-κB-activated high-risk GBMs. Taken together, a 9-gene methylation signature was identified as an independent GBM prognosticator and could be used for GBM risk stratification. Prosurvival NF-κB pathway activation characterized high-risk patients with poor prognosis, indicating it to be a therapeutic target. Cancer Res; 73(22); 6563–73. ©2013 AACR.
Data from Phase I Trial of Recombinant Modified Vaccinia Ankara Encoding Epstein–Barr Viral Tumor Antigens in Nasopharyngeal Carcinoma Patients
Authors: Hui Edwin P. , Taylor Graham S. , Jia Hui , Ma Brigette B.Y. , Chan Stephen L. , Ho Rosalie , Wong Wai-Lap , Wilson Steven , Johnson Benjamin F. , Edwards Ceri , Stocken Deborah D. , Rickinson Alan B. , Steven Neil M. , Chan Anthony T.C.
Published: March 2024

Abstract
Epstein–Barr virus (EBV) is associated with several malignancies including nasopharyngeal carcinoma, a high incidence tumor in Chinese populations, in which tumor cells express the two EBV antigens EB nuclear antigen 1 (EBNA1) and latent membrane protein 2 (LMP2). Here, we report the phase I trial of a recombinant vaccinia virus, MVA-EL, which encodes an EBNA1/LMP2 fusion protein designed to boost T-cell immunity to these antigens. The vaccine was delivered to Hong Kong patients with nasopharyngeal carcinoma to determine a safe and immunogenic dose. The patients, all in remission more than 12 weeks after primary therapy, received three intradermal MVA-EL vaccinations at three weekly intervals, using five escalating dose levels between 5 × 107 and 5 × 108 plaque-forming unit (pfu). Blood samples were taken during prescreening, immediately before vaccination, one week afterward and at intervals up to one year later. Immunogenicity was tested by IFN-γ ELIspot assays using complete EBNA1 and LMP2 15-mer peptide mixes and known epitope peptides relevant to patient MHC type. Eighteen patients were treated, three per dose level one to four and six at the highest dose, without dose-limiting toxicity. T-cell responses to one or both vaccine antigens were increased in 15 of 18 patients and, in many cases, were mapped to known CD4 and CD8 epitopes in EBNA1 and/or LMP2. The range of these responses suggested a direct relationship with vaccine dose, with all six patients at the highest dose level giving strong EBNA1/LMP2 responses. We concluded that MVA-EL is both safe and immunogenic, allowing the highest dose to be forwarded to phase II studies examining clinical benefit. Cancer Res; 73(6); 1676–88. ©2012 AACR.
Data from Re-engineering Vesicular Stomatitis Virus to Abrogate Neurotoxicity, Circumvent Humoral Immunity, and Enhance Oncolytic Potency
Authors: Muik Alexander , Stubbert Lawton J. , Jahedi Roza Z. , Geiβ Yvonne , Kimpel Janine , Dold Catherine , Tober Reinhard , Volk Andreas , Klein Sabine , Dietrich Ursula , Yadollahi Beta , Falls Theresa , Miletic Hrvoje , Stojdl David , Bell John C. , von Laer Dorothee
Published: March 2024

Abstract
As cancer treatment tools, oncolytic viruses (OV) have yet to realize what some see as their ultimate clinical potential. In this study, we have engineered a chimeric vesicular stomatitis virus (VSV) that is devoid of its natural neurotoxicity while retaining potent oncolytic activity. The envelope glycoprotein (G) of VSV was replaced with a variant glycoprotein of the lymphocytic choriomeningitis virus (LCMV-GP), creating a replicating therapeutic, rVSV(GP), that is benign in normal brain but can effectively eliminate brain cancer in multiple preclinical tumor models in vivo. Furthermore, it can be safely administered systemically to mice and displays greater potency against a spectrum of human cancer cell lines than current OV candidates. Remarkably, rVSV(GP) escapes humoral immunity, thus, for the first time, allowing repeated systemic OV application without loss of therapeutic efficacy. Taken together, rVSV(GP) offers a considerably improved OV platform that lacks several of the major drawbacks that have limited the clinical potential of this technology to date. Cancer Res; 74(13); 3567–78. ©2014 AACR.
Data from Doxorubicin Eliminates Myeloid-Derived Suppressor Cells and Enhances the Efficacy of Adoptive T-Cell Transfer in Breast Cancer
Authors: Alizadeh Darya , Trad Malika , Hanke Neale T. , Larmonier Claire B. , Janikashvili Nona , Bonnotte Bernard , Katsanis Emmanuel , Larmonier Nicolas
Published: March 2024

Abstract
Myeloid-derived suppressor cells (MDSC) expand in tumor-bearing hosts and play a central role in cancer immune evasion by inhibiting adaptive and innate immunity. They therefore represent a major obstacle for successful cancer immunotherapy. Different strategies have thus been explored to deplete and/or inactivate MDSC in vivo. Using a murine mammary cancer model, we demonstrated that doxorubicin selectively eliminates MDSC in the spleen, blood, and tumor beds. Furthermore, residual MDSC from doxorubicin-treated mice exhibited impaired suppressive function. Importantly, the frequency of CD4+ and CD8+ T lymphocytes and consequently the effector lymphocytes or natural killer (NK) to suppressive MDSC ratios were significantly increased following doxorubicin treatment of tumor-bearing mice. In addition, the proportion of NK and cytotoxic T cell (CTL) expressing perforin and granzyme B and of CTL producing IFN-γ was augmented by doxorubicin administration. Of therapeutic relevance, this drug efficiently combined with Th1 or Th17 lymphocytes to suppress tumor development and metastatic disease. MDSC isolated from patients with different types of cancer were also sensitive to doxorubicin-mediated cytotoxicity in vitro. These results thus indicate that doxorubicin may be used not only as a direct cytotoxic drug against tumor cells, but also as a potent immunomodulatory agent that selectively impairs MDSC-induced immunosuppression, thereby fostering the efficacy of T-cell–based immunotherapy. Cancer Res; 74(1); 104–18. ©2013 AACR.
Data from Microbiota Modulate Tumoral Immune Surveillance in Lung through a γδT17 Immune Cell-Dependent Mechanism
Authors: Cheng Min , Qian Liting , Shen Guodong , Bian Geng , Xu Tingjuan , Xu Weiping , Shen Gan , Hu Shilian
Published: March 2024

Abstract
Commensal bacteria are crucial to maintain immune homeostasis in mucosal tissues and disturbances in their ecology can affect disease susceptibility. Here, we report evidence that commensal bacteria shape the efficiency of immune surveillance in mucosal tissues. Antibiotic-treated (Abt) mice were more susceptible to development of engrafted B16/F10 melanoma and Lewis lung carcinoma, exhibiting a shortened mean survival time with more numerous and larger tumor foci in the lungs. The defective antitumor response of Abt mice was independent of dehydration caused by antibiotics. Host defenses relied upon intact commensal bacteria with no class specificity. Mechanistic investigations revealed a defective induction of the γδT17 cell response in lungs of Abt mice; here, more aggressive tumor development was observed, possibly related to a reduction in IL6 and IL23 expression there. Adding normal γδT cells or supplementing IL17 restored the impaired immune surveillance phenotype in Abt mice. Overall, our results demonstrated the importance of commensal bacteria in supporting the host immune response against cancer, defined an important role for γδT17 responses in the mechanism, and suggested deleterious effects of antibiotic treatment on cancer susceptibility and progression. Cancer Res; 74(15); 4030–41. ©2014 AACR.
Data from FOXP3 Regulates Sensitivity of Cancer Cells to Irradiation by Transcriptional Repression of BRCA1
Authors: Li Weiquan , Katoh Hiroto , Wang Lizhong , Yu Xiaochun , Du Zhanwen , Yan Xiaoli , Zheng Pan , Liu Yang
Published: March 2024

Abstract
FOXP3 is an X-linked tumor suppressor gene and a master regulator in T regulatory cell function. This gene has been found to be mutated frequently in breast and prostate cancers and to inhibit tumor cell growth, but its functional significance in DNA repair has not been studied. We found that FOXP3 silencing stimulates homologous recombination-mediated DNA repair and also repair of γ-irradiation-induced DNA damage. Expression profiling and chromatin-immunoprecipitation analyses revealed that FOXP3 regulated the BRCA1-mediated DNA repair program. Among 48 FOXP3-regulated DNA repair genes, BRCA1 and 12 others were direct targets of FOXP3 transcriptional control. Site-specific interaction of FOXP3 with the BRCA1 promoter repressed its transcription. Somatic FOXP3 mutants identified in breast cancer samples had reduced BRCA1 repressor activity, whereas FOXP3 silencing and knock-in of a prostate cancer-derived somatic FOXP3 mutant increased the radioresistance of cancer cells. Together our findings provide a missing link between FOXP3 function and DNA repair programs. Cancer Res; 73(7); 2170–80. ©2012 AACR.
Data from Sphingosine Kinase 2 Promotes Acute Lymphoblastic Leukemia by Enhancing MYC Expression
Authors: Wallington-Beddoe Craig T. , Powell Jason A. , Tong Daochen , Pitson Stuart M. , Bradstock Kenneth F. , Bendall Linda J.
Published: March 2024

Abstract
Sphingosine kinase 2 (SK2) may have utility as a prognostic marker in inflammatory diseases such as cancer in which it has been rationalized as a candidate therapeutic target. Here, we show that SK2 has an oncogenic role in acute lymphoblastic leukemia (ALL) by influencing expression of MYC. Genetic ablation of SK2 impaired leukemia development in a mouse model of ALL and pharmacologic inhibition extended survival in mouse xenograft models of human disease. SK2 attenuation in both the settings reduced MYC expression in leukemic cells, with reduced levels of acetylated histone H3 within the MYC gene associated with reduced levels of MYC protein and expression of MYC-regulated genes. Our results demonstrated that SK2 regulates MYC, which has a pivotal role in hematologic malignancies, providing a preclinical proof of concept for this pathway as a broad-based therapeutic target in this setting. Cancer Res; 74(10); 2803–15. ©2014 AACR.
Data from Anti-CD20 Antibody Promotes Cancer Escape via Enrichment of Tumor-Evoked Regulatory B Cells Expressing Low Levels of CD20 and CD137L
Authors: Bodogai Monica , Lee Chang Catalina , Wejksza Katarzyna , Lai Jinping , Merino Maria , Wersto Robert P. , Gress Ronald E. , Chan Andrew C. , Hesdorffer Charles , Biragyn Arya
Published: March 2024

Abstract
The possible therapeutic benefits of B-cell depletion in combating tumoral immune escape have been debated. In support of this concept, metastasis of highly aggressive 4T1 breast cancer cells in mice can be abrogated by inactivation of tumor-evoked regulatory B cells (tBreg). Here, we report the unexpected finding that B-cell depletion by CD20 antibody will greatly enhance cancer progression and metastasis. Both murine and human tBregs express low levels of CD20 and, as such, anti-CD20 mostly enriches for these cells. In the 4T1 model of murine breast cancer, this effect of enriching for tBregs suggests that B-cell depletion by anti-CD20 may not be beneficial at all in some cancers. In contrast, we show that in vivo–targeted stimulation of B cells with CXCL13-coupled CpG oligonucleotides (CpG-ODN) can block cancer metastasis by inhibiting CD20Low tBregs. Mechanistic investigations suggested that CpG-ODN upregulates low surface levels of 4-1BBL on tBregs to elicit granzyme B–expressing cytolytic CD8+ T cells, offering some explanative power for the effect. These findings underscore the immunotherapeutic importance of tBreg inactivation as a strategy to enhance cancer therapy by targeting both the regulatory and activating arms of the immune system in vivo. Cancer Res; 73(7); 2127–38. ©2013 AACR.
Data from xCT Inhibition Depletes CD44v-Expressing Tumor Cells That Are Resistant to EGFR-Targeted Therapy in Head and Neck Squamous Cell Carcinoma
Authors: Yoshikawa Momoko , Tsuchihashi Kenji , Ishimoto Takatsugu , Yae Toshifumi , Motohara Takeshi , Sugihara Eiji , Onishi Nobuyuki , Masuko Takashi , Yoshizawa Kunio , Kawashiri Shuichi , Mukai Makio , Asoda Seiji , Kawana Hiromasa , Nakagawa Taneaki , Saya Hideyuki , Nagano Osamu
Published: March 2024

Abstract
The targeting of antioxidant systems that allow stem-like cancer cells to avoid the adverse consequences of oxidative stress might be expected to improve the efficacy of cancer treatment. Here, we show that head and neck squamous cell carcinoma (HNSCC) cells that express variant isoforms of CD44 (CD44v) rely on the activity of the cystine transporter subunit xCT for control of their redox status. xCT inhibition selectively induces apoptosis in CD44v-expressing tumor cells without affecting CD44v-negative differentiated cells in the same tumor. In contrast to CD44v-expressing undifferentiated cells, CD44v-negative differentiated cells manifest EGF receptor (EGFR) activation and rely on EGFR activity for their survival. Combined treatment with inhibitors of xCT-dependent cystine transport and of EGFR resulted in a synergistic reduction of EGFR-expressing HNSCC tumor growth. Thus, xCT-targeted therapy may deplete CD44v-expressing undifferentiated HNSCC cells and concurrently sensitize the remaining differentiating cells to available treatments including EGFR-targeted therapy. Cancer Res; 73(6); 1855–66. ©2012 AACR.
Data from The HSP90 Inhibitor Ganetespib Synergizes with the MET Kinase Inhibitor Crizotinib in both Crizotinib-Sensitive and -Resistant MET-Driven Tumor Models
Authors: Miyajima Naoto , Tsutsumi Shinji , Sourbier Carole , Beebe Kristin , Mollapour Mehdi , Rivas Candy , Yoshida Soichiro , Trepel Jane B. , Huang Ying , Tatokoro Manabu , Shinohara Nobuo , Nonomura Katsuya , Neckers Len
Published: March 2024

Abstract
The proto-oncogene MET is aberrantly activated via overexpression or mutation in numerous cancers, making it a prime anticancer molecular target. However, the clinical success of MET-directed tyrosine kinase inhibitors (TKI) has been limited due, in part, to mutations in the MET kinase domain that confer therapeutic resistance. Circumventing this problem remains a key challenge to improving durable responses in patients receiving MET-targeted therapy. MET is an HSP90-dependent kinase, and in this report we show that HSP90 preferentially interacts with and stabilizes activated MET, regardless of whether the activation is ligand-dependent or is a consequence of kinase domain mutation. In contrast, many MET-TKI show a preference for the inactive form of the kinase, and activating mutations in MET can confer resistance. Combining the HSP90 inhibitor ganetespib with the MET-TKI crizotinib achieves synergistic inhibition of MET, its downstream signaling pathways, and tumor growth in both TKI-sensitive and -resistant MET-driven tumor models. These data suggest that inclusion of an HSP90 inhibitor can partially restore TKI sensitivity to previously resistant MET mutants, and they provide the foundation for clinical evaluation of this therapeutic combination in patients with MET-driven cancers. Cancer Res; 73(23); 7022–33. ©2013 AACR.
Data from LSECtin Expressed on Melanoma Cells Promotes Tumor Progression by Inhibiting Antitumor T-cell Responses
Authors: Xu Feng , Liu Jing , Liu Di , Liu Biao , Wang Min , Hu Zhiyuan , Du Xuemei , Tang Li , He Fuchu
Published: March 2024

Abstract
Therapeutic antibodies that target T-cell co-inhibitory molecules display potent antitumor effects in multiple types of cancer. LSECtin is a cell surface lectin of the DC-SIGN family expressed in dendritic cells that inhibits T-cell responses. LSECtin limits T-cell activity in infectious disease, but it has not been studied in cancer. Here we report the finding that LSECtin is expressed commonly in melanomas where it blunts tumor-specific T-cell responses. When expressed in B16 melanoma cells, LSECtin promoted tumor growth, whereas its blockade slowed tumor growth in either wild-type or LSECtin-deficient mice. The tumor-promoting effects of LSECtin were abrogated in Rag1−/− mice or in response to CD4+ or CD8+ T-cell depletion. Mechanistic investigations determined that LSECtin inhibited the proliferation of tumor-specific effector T cells by downregulating the cell cycle kinases CDK2, CDK4, and CDK6. Accordingly, as expressed in B16, tumor cells LSECtin inhibited tumor-specific T-cell responses relying upon proliferation in vitro and in vivo. Notably, LSECtin interacted with the co-regulatory molecule LAG-3, the blockade of which restored IFNγ secretion that was reduced by melanoma-derived expression of LSECtin. Together, our findings reveal that common expression of LSECtin in melanoma cells engenders a mechanism of immune escape, with implications for novel immunotherapeutic combination strategies. Cancer Res; 74(13); 3418–28. ©2014 AACR.
Data from Distinguishing between Benign and Malignant Melanocytic Nevi by In Vivo Multiphoton Microscopy
Authors: Balu Mihaela , Kelly Kristen M. , Zachary Christopher B. , Harris Ronald M. , Krasieva Tatiana B. , König Karsten , Durkin Anthony J. , Tromberg Bruce J.
Published: March 2024

Abstract
Monitoring of atypical nevi is an important step in early detection of melanoma, a clinical imperative in preventing the disease progression. Current standard diagnosis is based on biopsy and histopathologic examination, a method that is invasive and highly dependent upon physician experience. In this work, we used a clinical multiphoton microscope to image in vivo and noninvasively melanocytic nevi at three different stages: common nevi without dysplastic changes, dysplastic nevi with structural and architectural atypia, and melanoma. We analyzed multiphoton microscopy (MPM) images corresponding to 15 lesions (five in each group) both qualitatively and quantitatively. For the qualitative analysis, we identified the morphologic features characteristic of each group. MPM images corresponding to dysplastic nevi and melanoma were compared with standard histopathology to determine correlations between tissue constituents and morphology and to evaluate whether standard histopathology criteria can be identified in the MPM images. Prominent qualitative correlations included the morphology of epidermal keratinocytes, the appearance of nests of nevus cells surrounded by collagen fibers, and the structure of the epidermal–dermal junction. For the quantitative analysis, we defined a numerical multiphoton melanoma index (MMI) based on three-dimensional in vivo image analysis that scores signals derived from two-photon excited fluorescence, second harmonic generation, and melanocyte morphology features on a continuous 9-point scale. Indices corresponding to common nevi (0–1), dysplastic nevi (1–4), and melanoma (5–8) were significantly different (P < 0.05), suggesting the potential of the method to distinguish between melanocytic nevi in vivo. Cancer Res; 74(10); 2688–97. ©2014 AACR.
Data from Chemotherapy Acts as an Adjuvant to Convert the Tumor Microenvironment into a Highly Permissive State for Vaccination-Induced Antitumor Immunity
Authors: Kang Tae Heung , Mao Chih-Ping , Lee Sung Yong , Chen Alexander , Lee Ji-Hyun , Kim Tae Woo , Alvarez Ronald D. , Roden Richard B.S. , Pardoll Drew , Hung Chien-Fu , Wu T.-C.
Published: March 2024

Abstract
Multiple classes of pharmacologic agents have the potential to induce the expression and release of proinflammatory factors from dying tumor cells. As a result, these cells can in theory elicit an immune response through various defined mechanisms to permanently eradicate disseminated cancer. However, the impact of chemotherapy on the tumor-specific immune response in the context of the tumor microenvironment is largely unknown. Within the tumor microenvironment, the immune response promoted by chemotherapy is antagonized by an immune-suppressive milieu, and the balance of these opposing forces dictates the clinical course of disease. Here, we report that high antigen exposure within the tumor microenvironment following chemotherapy is sufficient to skew this balance in favor of a productive immune response. In elevating antigen exposure, chemotherapy can achieve long-term control of tumor progression without the need of an additional adjuvant. We found that chemotherapy initiated this phenomenon in the tumor microenvironment through an accumulation of dendritic cells, which stimulated CD8+ T cells and the type I IFN pathway. From this conceptual base, we developed a simple approach to cancer therapy combining chemotherapy and vaccination that may be widely applicable. Cancer Res; 73(8); 2493–504. ©2013 AACR.
Data from Biallelic DICER1 Mutations in Sporadic Pleuropulmonary Blastoma
Authors: Seki Masafumi , Yoshida Kenichi , Shiraishi Yuichi , Shimamura Teppei , Sato Yusuke , Nishimura Riki , Okuno Yusuke , Chiba Kenichi , Tanaka Hiroko , Kato Keisuke , Kato Motohiro , Hanada Ryoji , Nomura Yuko , Park Myoung-Ja , Ishida Toshiaki , Oka Akira , Igarashi Takashi , Miyano Satoru , Hayashi Yasuhide , Ogawa Seishi , Takita Junko
Published: March 2024

Abstract
Pleuropulmonary blastoma (PPB) is a rare pediatric malignancy whose pathogens are poorly understood. Recent reports suggest that germline mutations in the microRNA-processing enzyme DICER1 may contribute to PPB development. To investigate the genetic basis of this cancer, we performed whole-exome sequencing or targeted deep sequencing of multiple cases of PPB. We found biallelic DICER1 mutations to be very common, more common than TP53 mutations also found in many tumors. Somatic ribonuclease III (RNase IIIb) domain mutations were identified in all evaluable cases, either in the presence or absence of nonsense/frameshift mutations. Most cases had mutated DICER1 alleles in the germline with or without an additional somatic mutation in the remaining allele, whereas other cases displayed somatic mutations exclusively where the RNase IIIb domain was invariably affected. Our results highlight the role of RNase IIIb domain mutations in DICER1 along with TP53 inactivation in PPB pathogenesis. Cancer Res; 74(10); 2742–9. ©2014 AACR.
Data from Collections of Simultaneously Altered Genes as Biomarkers of Cancer Cell Drug Response
Authors: Masica David L. , Karchin Rachel
Published: March 2024

Abstract
Computational analysis of cancer pharmacogenomics data has resulted in biomarkers predictive of drug response, but the majority of response is not captured by current methods. Methods typically select single biomarkers or groups of related biomarkers but do not account for response that is strictly dependent on many simultaneous genetic alterations. This shortcoming reflects the combinatorics and multiple-testing problem associated with many-body biologic interactions. We developed a novel approach, Multivariate Organization of Combinatorial Alterations (MOCA), to partially address these challenges. Extending on previous work that accounts for pairwise interactions, the approach rapidly combines many genomic alterations into biomarkers of drug response, using Boolean set operations coupled with optimization; in this framework, the union, intersection, and difference Boolean set operations are proxies of molecular redundancy, synergy, and resistance, respectively. The algorithm is fast, broadly applicable to cancer genomics data, is of immediate use for prioritizing cancer pharmacogenomics experiments, and recovers known clinical findings without bias. Furthermore, the results presented here connect many important, previously isolated observations. Cancer Res; 73(6); 1699–708. ©2012 AACR.
Data from HNRNPAB Induces Epithelial–Mesenchymal Transition and Promotes Metastasis of Hepatocellular Carcinoma by Transcriptionally Activating SNAIL
Authors: Zhou Zheng-Jun , Dai Zhi , Zhou Shao-Lai , Hu Zhi-Qiang , Chen Qing , Zhao Yi-Ming , Shi Ying-Hong , Gao Qiang , Wu Wei-Zhong , Qiu Shuang-Jian , Zhou Jian , Fan Jia
Published: March 2024

Abstract
Expression of heterogeneous nuclear ribonucleoprotein AB (HNRNPAB) has been reported to be dysregulated in tumors, but its specific contributions to tumor formation and progression are not fully understood. Here, we demonstrate that HNRNPAB is overexpressed in highly metastatic cells and tumor tissues from patients with hepatocellular carcinoma (HCC) with recurrence. We found that HNRNPAB overexpression promoted epithelial–mesenchymal transition (EMT) in a manner associated with HCC metastasis in vitro and in vivo. RNA interference-mediated silencing of the EMT factor SNAIL attenuated HNRNPAB-enhanced cell invasion in vitro and lung metastasis in vivo. Mechanistically, HNRNPAB acted to transactivate SNAIL1 transcription, which in turn inhibited transcription of the pivotal SNAIL target gene E-cadherin. Overexpression of HNRNPAB in HCC samples correlated with higher SNAIL levels, shorter overall survival, and higher tumor recurrence. HNRNPAB overexpression, alone or in combination with SNAIL, was found to be a significant independent risk factor for recurrence and survival after curative resection. In conclusion, our findings define HNRNPAB as an activator of EMT and metastasis in HCC that predicts poor clinical outcomes. Cancer Res; 74(10); 2750–62. ©2014 AACR.
Data from Neuromedin U: A Candidate Biomarker and Therapeutic Target to Predict and Overcome Resistance to HER-Tyrosine Kinase Inhibitors
Authors: Rani Sweta , Corcoran Claire , Shiels Liam , Germano Serena , Breslin Susan , Madden Stephen , McDermott Martina S. , Browne Brigid C. , O'Donovan Norma , Crown John , Gogarty Martina , Byrne Annette T. , O'Driscoll Lorraine
Published: March 2024

Abstract
Intrinsic and acquired resistance to HER-targeting drugs occurs in a significant proportion of HER2-overexpressing breast cancers. Thus, there remains a need to identify predictive biomarkers that could improve patient selection and circumvent these types of drug resistance. Here, we report the identification of neuromedin U (NmU) as an extracellular biomarker in cells resistant to HER-targeted drugs. NmU overexpression occurred in cells with acquired or innate resistance to lapatinib, trastuzumab, neratinib, and afatinib, all of which displayed a similar trend upon short-term exposure, suggesting NmU induction may be an early response. An analysis of 3,489 cases of breast cancer showed NmU to be associated with poor patient outcome, particularly those with HER2-overexpressing tumors independent of established prognostic indicators. Ectopic overexpression of NmU in drug-sensitive cells conferred resistance to all HER-targeting drugs, whereas RNAi-mediated attenuation sensitized cells exhibiting acquired or innate drug resistance. Mechanistic investigations suggested that NmU acted through HSP27 as partner protein to stabilize HER2 protein levels. We also obtained evidence of functional NmU receptors on HER2-overexpressing cells, with the addition of exogenous NmU eliciting an elevation in HER2 and EGFR expression along with drug resistance. Finally, we found that NmU seemed to function in cell motility, invasion, and anoikis resistance. In vivo studies revealed that NmU attenuation impaired tumor growth and metastasis. Taken together, our results defined NmU as a candidate drug response biomarker for HER2-overexpressing cancers and as a candidate therapeutic target to limit metastatic progression and improve the efficacy of HER-targeted drugs. Cancer Res; 74(14); 3821–33. ©2014 AACR.
Data from Impact of Tumor Progression on Cancer Incidence Curves
Authors: Luebeck E. Georg , Curtius Kit , Jeon Jihyoun , Hazelton William D.
Published: March 2024

Abstract
Cancer arises through a multistage process, but it is not fully clear how this process influences the age-specific incidence curve. Studies of colorectal and pancreatic cancer using the multistage clonal expansion (MSCE) model have identified two phases of the incidence curves. One phase is linear, beginning about age of 60 years, suggesting that at least two rare rate-limiting mutations occur before clonal expansion of premalignant cells. A second phase is exponential, seen in early-onset cancers occurring before the age of 60 years that are associated with premalignant clonal expansion. Here, we extend the MSCE model to include clonal expansion of malignant cells, an advance that permits study of the effects of tumor growth and extinction on the incidence of colorectal, gastric, pancreatic, and esophageal adenocarcinomas in the digestive tract. After adjusting the age-specific incidence for birth-cohort and calendar-year trends, we found that initiating mutations and premalignant cell kinetics can explain the primary features of the incidence curve. However, we also found that the incidence data of these cancers harbored information on the kinetics of malignant clonal expansion before clinical detection, including tumor growth rates and extinction probabilities on three characteristic time scales for tumor progression. In addition, the data harbored information on the mean sojourn times for premalignant clones until occurrence of either the first malignant cell or the first persistent (surviving) malignant clone. Finally, the data also harbored information on the mean sojourn time of persistent malignant clones to the time of diagnosis. In conclusion, cancer incidence curves can harbor significant information about hidden processes of tumor initiation, premalignant clonal expansion, and malignant transformation, and even some limited information on tumor growth before clinical detection. Cancer Res; 73(3); 1086–96. ©2012 AACR.
Data from Dual Functions of the Homeoprotein DLX4 in Modulating Responsiveness of Tumor Cells to Topoisomerase II-Targeting Drugs
Authors: Trinh Bon Q. , Ko Song Yi , Barengo Nicolas , Lin Shiaw-Yih , Naora Honami
Published: March 2024

Abstract
Topoisomerase II (TOP2)-targeting poisons such as anthracyclines and etoposide are commonly used for cancer chemotherapy and kill tumor cells by causing accumulation of DNA double-strand breaks (DSB). Several lines of evidence indicate that overexpression of TOP2A, the gene encoding topoisomerase IIα, increases sensitivity of tumor cells to TOP2 poisons, but it is not clear why some TOP2A-overexpressing (TOP2A-High) tumors respond poorly to these drugs. In this study, we identified that TOP2A expression is induced by DLX4, a homeoprotein that is overexpressed in breast and ovarian cancers. Analysis of breast cancer datasets revealed that TOP2A-high cases that also highly expressed DLX4 responded more poorly to anthracycline-based chemotherapy than TOP2A-high cases that expressed DLX4 at low levels. Overexpression of TOP2A alone in tumor cells increased the level of DSBs induced by TOP2 poisons. In contrast, DLX4 reduced the level of TOP2 poison-induced DSBs irrespective of its induction of TOP2A. DLX4 did not stimulate homologous recombination–mediated repair of DSBs. However, DLX4 interacted with Ku proteins, stimulated DNA-dependent protein kinase activity, and increased erroneous end-joining repair of DSBs. Whereas DLX4 did not reduce levels of TOP2 poison-induced DSBs in Ku-deficient cells, DLX4 stimulated DSB repair and reduced the level of TOP2 poison–induced DSBs when Ku was reconstituted in these cells. Our findings indicate that DLX4 induces TOP2A expression but reduces sensitivity of tumor cells to TOP2 poisons by stimulating Ku-dependent repair of DSBs. These opposing activities of DLX4 could explain why some TOP2A-overexpressing tumors are not highly sensitive to TOP2 poisons. Cancer Res; 73(2); 1000–10. ©2012 AACR.
Data from Activation of SOX2 Expression by BRD4-NUT Oncogenic Fusion Drives Neoplastic Transformation in NUT Midline Carcinoma
Authors: Wang Ranran , Liu Wei , Helfer Christine M. , Bradner James E. , Hornick Jason L. , Janicki Susan M. , French Christopher A. , You Jianxin
Published: March 2024

Abstract
BRD4 is implicated in the pathogenesis of a number of different cancers. It is also the target of translocation t(15;19) that accounts for the highly aggressive NUT midline carcinoma (NMC). We discovered that t(15;19) NMC cells display the ability to grow into stem cell–like spheres and express an exceptionally high level of the stem cell marker, SOX2. The BRD4-NUT fusion oncogene resulting from t(15;19) translocation is required for the abnormal activation of SOX2, which drives the stem cell–like proliferation and cellular transformation in NMC cells. SOX2 knockdown phenocopies the effects of BRD4-NUT inhibition, whereas ectopic SOX2 expression rescues the phenotype. The BRD4-NUT–induced abnormal SOX2 activation was observed in multiple NMC cell lines as well as in NMC primary tumors. We further demonstrate that BRD4-NUT oncoprotein recruits p300 to stimulate transcription activation and that inhibition of p300 represses SOX2 transcription in NMC cells. These studies identify this stem cell marker as a novel BRD4-NUT target that supports the highly aggressive transforming activity of t(15;19) carcinomas. Our study provides new mechanistic insights for understanding how alteration of BRD4 function by BRD4-NUT oncogene leads to the highly malignant NMC carcinoma. Because abnormal stem cell self-renewal is frequently observed during tumor formation and metastasis, the aberrant stem cell–like proliferation associated with BRD4 dysregulation observed in NMC carcinoma may have implications for studying the oncogenic mechanism of other BRD4-associated tumors. Cancer Res; 74(12); 3332–43. ©2014 AACR.
Data from FOXO3a Is a Major Target of Inactivation by PI3K/AKT Signaling in Aggressive Neuroblastoma
Authors: Santo Evan E. , Stroeken Peter , Sluis Peter V. , Koster Jan , Versteeg Rogier , Westerhout Ellen M.
Published: March 2024

Abstract
Neuroblastoma is a pediatric tumor of the peripheral sympathetic nervous system with a highly variable prognosis. Activation of the phosphoinositide 3-kinase (PI3K)/AKT pathway in neuroblastoma is correlated with poor patient prognosis, but the precise downstream effectors mediating this effect have not been determined. Here we identify the forkhead transcription factor FOXO3a as a key target of the PI3K/AKT pathway in neuroblastoma. FOXO3a expression was elevated in low-stage neuroblastoma tumors and normal embryonal neuroblasts, but reduced in late-stage neuroblastoma. Inactivation of FOXO3a by AKT was essential for neuroblastoma cell survival. Treatment of neuroblastoma cells with the dual PI3K/mTOR inhibitor PI-103 activated FOXO3a and triggered apoptosis. This effect was rescued by FOXO3a silencing. Conversely, apoptosis induced by PI-103 or the AKT inhibitor MK-2206 was potentiated by FOXO3a overexpression. Furthermore, levels of total or phosphorylated FOXO3a correlated closely with apoptotic sensitivity to MK-2206. In clinical specimens, there was an inverse relationship between gene expression signatures regulated by PI3K signaling and FOXO3a transcriptional activity. Moreover, high PI3K activity and low FOXO3a activity were each associated with an extremely poor prognosis. Our work indicates that expression of FOXO3a and its targets offer useful prognostic markers as well as biomarkers for PI3K/AKT inhibitor efficacy in neuroblastoma. Cancer Res; 73(7); 2189–98. ©2013 AACR.