bluuebunny/crossref_metadata_2025 huggingface dataset:
Data from MET and AXL Inhibitor NPS-1034 Exerts Efficacy against Lung Cancer Cells Resistant to EGFR Kinase Inhibitors Because of MET or AXL Activation
Authors: Rho Jin Kyung , Choi Yun Jung , Kim Seon Ye , Kim Tae Won , Choi Eun Kyung , Yoon Seon-Joo , Park Bu Man , Park Eunhye , Bae Jong Hwan , Choi Chang-Min , Lee Jae Cheol
Published: March 2024

Abstract
In non–small cell lung cancer (NSCLC) with epidermal growth factor receptor (EGFR) mutations, acquired resistance to EGFR-tyrosine kinase inhibitors (EGFR-TKI) can occur through a generation of bypass signals such as MET or AXL activation. In this study, we investigated the antitumor activity of NPS-1034, a newly developed drug that targets both MET and AXL, in NSCLC cells with acquired resistance to gefitinib or erlotinib (HCC827/GR and HCC827/ER, respectively). Characterization of H820 cells and evaluation of NPS-1034 efficacy in these cells were also performed. The resistance of HCC827/GR was mediated by MET activation, whereas AXL activation led to resistance in HCC827/ER. The combination of gefitinib or erlotinib with NPS-1034 synergistically inhibited cell proliferation and induced cell death in both resistant cell lines. Accordingly, suppression of Akt was noted only in the presence of treatment with both drugs. NPS-1034 was also effective in xenograft mouse models of HCC827/GR. Although the H820 cell line was reported previously to have T790M and MET amplification, we discovered that AXL was also activated in this cell line. There were no antitumor effects of siRNA or inhibitors specific for EGFR or MET, whereas combined treatment with AXL siRNA or NPS-1034 and EGFR-TKIs controlled H820 cells, suggesting that AXL is the main signal responsible for resistance. In addition, NPS-1034 inhibited cell proliferation as well as ROS1 activity in HCC78 cells with ROS1 rearrangement. Our results establish the efficacy of NPS-1034 in NSCLC cells rendered resistant to EGFR-TKIs because of MET or AXL activation or ROS1 rearrangement. Cancer Res; 74(1); 253–62. ©2013 AACR.
Data from RSF1 Is a Positive Regulator of NF-κB–Induced Gene Expression Required for Ovarian Cancer Chemoresistance
Authors: Yang Yeong-In , Ahn Ji-Hye , Lee Kyung-Tae , Shih Ie-Ming , Choi Jung-Hye
Published: March 2024

Abstract
Overexpression or amplification of the RSF1 gene has been associated with poor prognosis in various human cancers, including ovarian cancer. In previous work, RSF1 was identified as an amplified gene that facilitated the development of paclitaxel-resistant ovarian cancer. In the present study, we further demonstrated that RSF1 expression inversely correlated with paclitaxel response in patients with ovarian cancer and the mouse xenograft model. In addition, RSF1-overexpressing paclitaxel-resistant ovarian cancer cell lines were found to express elevated levels of genes regulated by NF-κB, including some involved with the evasion of apoptosis (CFLAR, XIAP, BCL2, and BCL2L1) and inflammation (PTGS2). In addition, ectopic expression of RSF1 using Tet-off inducible SKOV3 cells significantly enhanced NF-κB–dependent gene expression and transcriptional activation of NF-κB. An RSF1 knockdown using short hairpin RNAs suppressed these same pathways. Moreover, pretreatment with NF-κB inhibitors or downregulation of NF-κB–regulated gene expression considerably enhanced paclitaxel sensitivity in RSF1-overexpressing OVCAR3 and/or RSF1-induced SKOV3 cells. A coimmunoprecipitation assay revealed that RSF1 interacts with NF-κB and CREB-binding protein, a ubiquitous coactivator for NF-κB. Recruitment of RSF1 to the NF-κB binding element in the PTGS2 and XIAP promoters was demonstrated by the chromatin immunoprecipitation assay. Furthermore, hSNF2H, a well-known binding partner of RSF1, was partially involved in the interaction between RSF1 and NF-κB. Taken together, these data suggest that RSF1 may function as a coactivator for NF-κB, consequently augmenting expression of genes necessary for the development of chemoresistance in ovarian cancer cells. Cancer Res; 74(8); 2258–69. ©2014 AACR.
Data from Induction of Immunoregulatory CD271+ Cells by Metastatic Tumor Cells That Express Human Endogenous Retrovirus H
Authors: Kudo-Saito Chie , Yura Masahiro , Yamamoto Ryusuke , Kawakami Yutaka
Published: March 2024

Abstract
Human endogenous retroviruses (HERV) are associated with many diseases such as autoimmune diseases and cancer. Although the frequent expression of a variety of HERVs in tumor cells has been demonstrated, their functional contributions in cancer are as yet unclear. Intriguingly, HERVs and other retroviruses include an immunosuppressive domain in their transmembrane envelope proteins, but its mechanism of action and cancer relevance are obscure. In this study, we demonstrate that the human endogenous retrovirus HERV-H has a critical role in tumor metastasis and immune escape. We found that expression of herv-h mRNA was elevated in metastatic tumor cells undergoing epithelial-to-mesenchymal transition (EMT) and in primary tumor tissues from advanced colon cancer. The immunosuppressive peptide H17 derived from HERV-H was sufficient to induce EMT in tumor cells that expressed low levels of HERV-H, and it amplified this event within the tumor microenvironment. H17 also stimulated CCL19 expression in tumor cells, which in turn recruited and expanded a population of pluripotent immunoregulatory CD271+ cells, which included mesenchymal stem cells and myeloid-derived suppressor cells. In tumor tissues from patients with advanced colon cancer, we confirmed that CD271+ cells were increased in HERV-H+CCL19+ tumor tissues. Notably, RNAi-mediated change of HERV-H or CCL19, or depletion of CD271+ cells, improved immune responses in vitro and in vivo accompanied by tumor regression. Together, our results argued that HERV-H is a critical determinant of immune escape in cancer, suggesting its candidacy as a promising therapeutic target to treat patients with advanced cancer. Cancer Res; 74(5); 1361–70. ©2014 AACR.
Data from HAVCR/KIM-1 Activates the IL-6/STAT-3 Pathway in Clear Cell Renal Cell Carcinoma and Determines Tumor Progression and Patient Outcome
Authors: Cuadros Thaïs , Trilla Enric , Sarró Eduard , Vilà Maya R. , Vilardell Jordi , de Torres Inés , Salcedo Mayte , López-Hellin Joan , Sánchez Alex , Ramón y Cajal Santiago , Itarte Emilio , Morote Juan , Meseguer Anna
Published: March 2024

Abstract
Renal cell carcinoma (RCC), the third most prevalent urological cancer, claims more than 100,000 lives/year worldwide. The clear cell variant (ccRCC) is the most common and aggressive subtype of this disease. While commonly asymptomatic, more than 30% of ccRCC are diagnosed when already metastatic, resulting in a 95% mortality rate. Notably, nearly one-third of organ-confined cancers treated by nephrectomy develop metastasis during follow-up care. At present, diagnostic and prognostic biomarkers to screen, diagnose, and monitor renal cancers are clearly needed. The gene encoding the cell surface molecule HAVCR1/KIM-1 is a suggested susceptibility gene for ccRCC and ectodomain shedding of this molecule may be a predictive biomarker of tumor progression. Microarray analysis of 769-P ccRCC-derived cells where HAVCR/KIM-1 levels have been upregulated or silenced revealed relevant HAVCR/KIM-1–related targets, some of which were further analyzed in a cohort of 98 ccRCC patients with 100 month follow-up. We found that HAVCR/KIM-1 activates the IL-6/STAT-3/HIF-1A axis in ccRCC-derived cell lines, which depends on HAVCR/KIM-1 shedding. Moreover, we found that pSTAT-3 S727 levels represented an independent prognostic factor for ccRCC patients. Our results suggest that HAVCR/KIM-1 upregulation in tumors might represent a novel mechanism to activate tumor growth and angiogenesis and that pSTAT-3 S727 is an independent prognostic factor for ccRCC. Cancer Res; 74(5); 1416–28. ©2014 AACR.
Data from miRNA-491-5p and GIT1 Serve as Modulators and Biomarkers for Oral Squamous Cell Carcinoma Invasion and Metastasis
Authors: Huang Wei-Chieh , Chan Shih-Hsuan , Jang Te-Hsuan , Chang Jer-Wei , Ko Ying-Chin , Yen Tzu-Chen , Chiang Shang-Lun , Chiang Wei-Fan , Shieh Tien-Yu , Liao Chun-Ta , Juang Jyh-Lyh , Wang Hsueh-Chun , Cheng Ann-Joy , Lu Ya-Ching , Wang Lu-Hai
Published: March 2024

Abstract
MicroRNAs offer tools to identify and treat invasive cancers. Using highly invasive isogenic oral squamous cell carcinoma (OSCC) cells, established using in vitro and in vivo selection protocols from poorly invasive parental cell populations, we used microarray expression analysis to identify a relative and specific decrease in miR-491-5p in invasive cells. Lower expression of miR-491-5p correlated with poor overall survival of patients with OSCCs. miR-491-5p overexpression in invasive OSCC cells suppressed their migratory behavior in vitro and lung metastatic behavior in vivo. We defined the G-protein—coupled receptor kinase-interacting protein 1 (GIT1)—as a direct target gene for miR-491-5p control. GIT1 overexpression was sufficient to rescue miR-491-5p–mediated inhibition of migration/invasion and lung metastasis. Conversely, GIT1 silencing phenocopied the ability of miR-491-5p to inhibit migration/invasion and metastasis of OSCC cells. Mechanistic investigations indicated that miR-491-5p overexpression or GIT1 attenuation reduced focal adhesions, with a concurrent decrease in steady-state levels of paxillin, phospho-paxillin, phospho-FAK, EGF/EGFR-mediated extracellular signal–regulated kinase (ERK1/2) activation, and MMP2/9 levels and activities. In clinical specimens of OSCCs, GIT1 levels were elevated relative to paired normal tissues and were correlated with lymph node metastasis, with expression levels of miR-491-5p and GIT1 correlated inversely in OSCCs, where they informed tumor grade. Together, our findings identify a functional axis for OSCC invasion that suggests miR-491-5p and GIT1 as biomarkers for prognosis in this cancer. Cancer Res; 74(3); 751–64. ©2013 AACR.
Data from Compensatory Functions and Interdependency of the DNA-Binding Domain of BRCA2 with the BRCA1–PALB2–BRCA2 Complex
Authors: Al Abo Muthana , Dejsuphong Donniphat , Hirota Kouji , Yonetani Yasukazu , Yamazoe Mitsuyoshi , Kurumizaka Hitoshi , Takeda Shunichi
Published: March 2024

Abstract
BRCA1, BRCA2, and PALB2 are key players in cellular tolerance to chemotherapeutic agents, including camptothecin, cisplatin, and PARP inhibitor. The N-terminal segment of BRCA2 interacts with PALB2, thus contributing to the formation of the BRCA1–PALB2–BRCA2 complex. To understand the role played by BRCA2 in this complex, we deleted its N-terminal segment and generated BRCA2ΔN mutant cells. Although previous studies have suggested that BRCA1–PALB2 plays a role in the recruitment of BRCA2 to DNA-damage sites, BRCA2ΔN mutant cells displayed a considerably milder phenotype than did BRCA2−/− null-deficient cells. We hypothesized that the DNA-binding domain (DBD) of BRCA2 might compensate for a defect in BRCA2ΔN that prevented stable interaction with PALB2. To test this hypothesis, we disrupted the DBD of BRCA2 in wild-type and BRCA2ΔN cells. Remarkably, although the resulting BRCA2ΔDBD cells displayed a moderate phenotype, the BRCA2ΔN+ΔDBD cells displayed a very severe phenotype, as did the BRCA2−/− cells, suggesting that the N-terminal segment and the DBD play a substantially overlapping role in the functionality of BRCA2. We also showed that the formation of both the BRCA1–PALB2–BRCA2 complex and the DBD is required for efficient recruitment of BRCA2 to DNA-damage sites. Our study revealed the essential role played by both the BRCA1–PALB2–BRCA2 complex and the DBD in the functionality of BRCA2, as each can compensate for the other in the recruitment of BRCA2 to DNA-damage sites. This knowledge adds to our ability to accurately predict the efficacy of antimalignant therapies for patients carrying mutations in the BRCA2 gene. Cancer Res; 74(3); 797–807. ©2013 AACR.
Data from Attenuation of microRNA-126 Expression That Drives CD34+38− Stem/Progenitor Cells in Acute Myeloid Leukemia Leads to Tumor Eradication
Authors: de Leeuw David C. , Denkers Fedor , Olthof Marjolein C. , Rutten Arjo P. , Pouwels Walter , Jan Schuurhuis Gerrit , Ossenkoppele Gert J. , Smit Linda
Published: March 2024

Abstract
Despite high remission rates after therapy, 60% to 70% of patients with acute myeloid leukemia (AML) do not survive 5 years after their initial diagnosis. The main cause of treatment failures may be insufficient eradication of a subpopulation of leukemic stem-like cells (LSC), which are thought to be responsible for relapse by giving rise to more differentiated leukemic progenitors (LP). To address the need for therapeutic targets in LSCs, we compared microRNA (miRNA) expression patterns in highly enriched healthy CD34+CD38− hematopoietic stem cells (HSC), CD34+CD38− LSCs, and CD34+CD38+ LPs, all derived from the same patients' bone marrow (BM) specimens. In this manner, we identified multiple differentially expressed miRNAs, in particular miR-126, which was highly expressed in HSCs and increased in LSCs compared with LPs, consistent with a stem-like cell function. High miR-126 expression in AML was associated with poor survival, higher chance of relapse, and expression of genes present in LSC/HSC signatures. Notably, attenuating miR-126 expression in AML cells reduced in vitro cell growth by inducing apoptosis, but did not affect the survival of normal BM in which it instead enhanced expansion of HSCs. Furthermore, targeting miR-126 in LSCs and LPs reduced their clonogenic capacity and eliminated leukemic cells, again in the absence of similar inhibitory effects on normal BM cells. Our results define miR-126 as a therapeutic focus to specifically eradicate LSCs and improve AML outcome. Cancer Res; 74(7); 2094–105. ©2014 AACR.
Data from Intratumoral Modeling of Gefitinib Pharmacokinetics and Pharmacodynamics in an Orthotopic Mouse Model of Glioblastoma
Authors: Sharma Jyoti , Lv Hua , Gallo James M.
Published: March 2024

Abstract
Like many solid tumors, glioblastomas are characterized by intratumoral biologic heterogeneity that may contribute to a variable distribution of drugs and their associated pharmacodynamic responses, such that the standard pharmacokinetic approaches based on analysis of whole-tumor homogenates may be inaccurate. To address this aspect of tumor pharmacology, we analyzed intratumoral pharmacokinetic/pharmacodynamic characteristics of the EGFR inhibitor gefitinib in mice with intracerebral tumors and developed corresponding mathematical models. Following a single oral dose of gefitinib (50 or 150 mg/kg), tumors were processed at selected times according to a novel brain tumor sectioning protocol that generated serial samples to measure gefitinib concentrations, phosphorylated extracellular signal-regulated kinase (pERK), and immunohistochemistry in 4 different regions of tumors. Notably, we observed up to 3-fold variations in intratumoral concentrations of gefitinib, but only up to half this variability in pERK levels. As we observed a similar degree of variation in the immunohistochemical index termed the microvessel pericyte index (MPI), a measure of permeability in the blood–brain barrier, we used MPI in a hybrid physiologically-based pharmacokinetic (PBPK) model to account for regional changes in drug distribution that were observed. Subsequently, the PBPK models were linked to a pharmacodynamic model that could account for the variability observed in pERK levels. Together, our tumor sectioning protocol enabled integration of the intratumoral pharmacokinetic/pharmacodynamic variability of gefitinib and immunohistochemical indices followed by the construction of a predictive PBPK/pharmacodynamic model. These types of models offer a mechanistic basis to understand tumor heterogeneity as it impacts the activity of anticancer drugs. Cancer Res; 73(16); 5242–52. ©2013 AACR.
Data from Reprogramming the Chromatin Landscape: Interplay of the Estrogen and Glucocorticoid Receptors at the Genomic Level
Authors: Miranda Tina B. , Voss Ty C. , Sung Myong-Hee , Baek Songjoon , John Sam , Hawkins Mary , Grøntved Lars , Schiltz R. Louis , Hager Gordon L.
Published: March 2024

Abstract
Cross-talk between estrogen receptors (ER) and glucocorticoid receptors (GR) has been shown to contribute to the development and progression of breast cancer. Importantly, the ER and GR status in breast cancer cells is a significant factor in determining the outcome of the disease. However, mechanistic details defining the cellular interactions between ER and GR are poorly understood. We investigated genome-wide binding profiles for ER and GR upon coactivation and characterized the status of the chromatin landscape. We describe a novel mechanism dictating the molecular interplay between ER and GR. Upon induction, GR modulates access of ER to specific sites in the genome by reorganization of the chromatin configuration for these elements. Binding to these newly accessible sites occurs either by direct recognition of ER response elements or indirectly through interactions with other factors. The unveiling of this mechanism is important for understanding cellular interactions between ER and GR and may represent a general mechanism for cross-talk between nuclear receptors in human disease. Cancer Res; 73(16); 5130–9. ©2013 AACR.
Data from Fusobacterium in Colonic Flora and Molecular Features of Colorectal Carcinoma
Authors: Tahara Tomomitsu , Yamamoto Eiichiro , Suzuki Hiromu , Maruyama Reo , Chung Woonbok , Garriga Judith , Jelinek Jaroslav , Yamano Hiro-o , Sugai Tamotsu , An Byonggu , Shureiqi Imad , Toyota Minoru , Kondo Yutaka , Estécio Marcos R.H. , Issa Jean-Pierre J.
Published: March 2024

Abstract
Fusobacterium species are part of the gut microbiome in humans. Recent studies have identified overrepresentation of Fusobacterium in colorectal cancer tissues, but it is not yet clear whether this is pathogenic or simply an epiphenomenon. In this study, we evaluated the relationship between Fusobacterium status and molecular features in colorectal cancers through quantitative real-time PCR in 149 colorectal cancer tissues, 89 adjacent normal appearing mucosae and 72 colonic mucosae from cancer-free individuals. Results were correlated with CpG island methylator phenotype (CIMP) status, microsatellite instability (MSI), and mutations in BRAF, KRAS, TP53, CHD7, and CHD8. Whole-exome capture sequencing data were also available in 11 cases. Fusobacterium was detectable in 111 of 149 (74%) colorectal cancer tissues and heavily enriched in 9% (14/149) of the cases. As expected, Fusobacterium was also detected in normal appearing mucosae from both cancer and cancer-free individuals, but the amount of bacteria was much lower compared with colorectal cancer tissues (a mean of 250-fold lower for Pan-fusobacterium). We found the Fusobacterium-high colorectal cancer group (FB-high) to be associated with CIMP positivity (P = 0.001), TP53 wild-type (P = 0.015), hMLH1 methylation positivity (P = 0.0028), MSI (P = 0.018), and CHD7/8 mutation positivity (P = 0.002). Among the 11 cases where whole-exome sequencing data were available, two that were FB-high cases also had the highest number of somatic mutations (a mean of 736 per case in FB-high vs. 225 per case in all others). Taken together, our findings show that Fusobacterium enrichment is associated with specific molecular subsets of colorectal cancers, offering support for a pathogenic role in colorectal cancer for this gut microbiome component. Cancer Res; 74(5); 1311–8. ©2014 AACR.
Data from B-cell Expansion and Lymphomagenesis Induced by Chronic CD40 Signaling Is Strictly Dependent on CD19
Authors: Hojer Caroline , Frankenberger Samantha , Strobl Lothar J. , Feicht Samantha , Djermanovic Kristina , Jagdhuber Franziska , Hömig-Hölzel Cornelia , Ferch Uta , Ruland Jürgen , Rajewsky Klaus , Zimber-Strobl Ursula
Published: March 2024

Abstract
CD40, a member of the TNF receptor family, is expressed on all mature B cells and on most B-cell lymphomas. Recently, we have shown that constitutive activation of CD40 signaling in B cells induced by a fusion protein consisting of the transmembrane part of the Epstein–Barr viral latent membrane protein 1 (LMP1) and the cytoplasmic part of CD40 (LMP1/CD40) drives B-cell lymphoma development in transgenic mice. Because LMP1/CD40-expressing B cells showed an upregulation of CD19, we investigated CD19's function in CD40-driven B-cell expansion and lymphomagenesis. Here, we demonstrate that ablation of CD19 in LMP1/CD40 transgenic mice resulted in a severe loss and reduced lifespan of mature B cells and completely abrogated development of B-cell lymphoma. CD19 is localized to lipid rafts and constitutively activated by the LMP1/CD40 fusion protein in B cells. We provide evidence that the improved survival and malignant transformation of LMP1/CD40-expressing B cells are dependent on activation of the MAPK Erk that is mediated through CD19 in a PI3K-dependent manner. Our data suggest that constitutively active CD40 is dependent on CD19 to transmit survival and proliferation signals. Moreover, we detected a similarly functioning prosurvival pathway involving phosphorylated CD19 and PI3K-dependent Erk phosphorylation in human diffuse large B-cell lymphoma cell lines. Our data provide evidence that CD19 plays an important role in transmitting survival and proliferation signals downstream of CD40 and therefore might be an interesting therapeutic target for the treatment of lymphoma undergoing chronic CD40 signaling. Cancer Res; 74(16); 4318–28. ©2014 AACR.
Data from Alarmin IL-33 Acts as an Immunoadjuvant to Enhance Antigen-Specific Tumor Immunity
Authors: Villarreal Daniel O. , Wise Megan C. , Walters Jewell N. , Reuschel Emma L. , Choi Min Joung , Obeng-Adjei Nyamekye , Yan Jian , Morrow Matthew P. , Weiner David B.
Published: March 2024

Abstract
Studies of interleukin (IL)-33 reveal a number of pleiotropic properties. Here, we report that IL-33 has immunoadjuvant effects in a human papilloma virus (HPV)–associated model for cancer immunotherapy where cell-mediated immunity is critical for protection. Two biologically active isoforms of IL-33 exist that are full-length or mature, but the ability of either isoform to function as a vaccine adjuvant that influences CD4 T helper 1 or CD8 T-cell immune responses is not defined. We showed that both IL-33 isoforms are capable of enhancing potent antigen-specific effector and memory T-cell immunity in vivo in a DNA vaccine setting. In addition, although both IL-33 isoforms drove robust IFN-γ responses, neither elevated secretion of IL-4 or immunoglobulin E levels. Further, both isoforms augmented vaccine-induced antigen-specific polyfunctional CD4+ and CD8+ T-cell responses, with a large proportion of CD8+ T cells undergoing plurifunctional cytolytic degranulation. Therapeutic studies indicated that vaccination with either IL-33 isoform in conjunction with an HPV DNA vaccine caused rapid and complete regressions in vivo. Moreover, IL-33 could expand the magnitude of antigen-specific CD8+ T-cell responses and elicit effector–memory CD8+ T cells. Taken together, our results support the development of these IL-33 isoforms as immunoadjuvants in vaccinations against pathogens, including in the context of antitumor immunotherapy. Cancer Res; 74(6); 1789–800. ©2014 AACR.
Data from EGF Receptor Activates MET through MAPK to Enhance Non–Small Cell Lung Carcinoma Invasion and Brain Metastasis
Authors: Breindel Jerrica L. , Haskins Jonathan W. , Cowell Elizabeth P. , Zhao Minghui , Nguyen Don X. , Stern David F.
Published: March 2024

Abstract
MET amplification as a mechanism of acquired resistance to EGF receptor (EGFR)-targeted therapies in non–small cell lung carcinoma (NSCLC) led to investigation of novel combinations of EGFR and MET kinase inhibitors. However, promiscuous interactions between MET and ERBB family members have made it difficult to evaluate the effects of MET on EGFR signaling, both independent of drug treatment and in the context of drug resistance. We addressed this issue by establishing a 32D model cell system wherein ERBBs or MET are expressed alone and in combination. Using this model, we determined that EGFR signaling is sufficient to induce MET phosphorylation, although MET activation is enhanced by coexpression of ERBB3. EGFR–MET cross-talk was not direct, but occurred by a combined regulation of MET levels and intermediary signaling through mitogen-activated protein kinases (MAPK). In NSCLCs harboring either wild-type or mutant EGFR, inhibiting EGFR or MAPK reduced MET activation and protein levels. Furthermore, MET signaling promoted EGFR-driven migration and invasion. Finally, EGFR–MET signaling was enhanced in a highly metastatic EGFR-mutant cell subpopulation, compared with the indolent parental line, and MET attenuation decreased the incidence of brain metastasis. Overall, our results establish that EGFR–MET signaling is critical for aggressive behavior of NSCLCs and rationalize its continued investigation as a therapeutic target for tumors harboring both wild-type and mutant EGFR at early stages of progression. Cancer Res; 73(16); 5053–65. ©2013 AACR.
Data from Cyclophilin B Supports Myc and Mutant p53-Dependent Survival of Glioblastoma Multiforme Cells
Authors: Choi Jae Won , Schroeder Mark A. , Sarkaria Jann N. , Bram Richard J.
Published: March 2024

Abstract
Glioblastoma multiforme is an aggressive, treatment-refractory type of brain tumor for which effective therapeutic targets remain important to identify. Here, we report that cyclophilin B (CypB), a prolyl isomerase residing in the endoplasmic reticulum (ER), provides an essential survival signal in glioblastoma multiforme cells. Analysis of gene expression databases revealed that CypB is upregulated in many cases of malignant glioma. We found that suppression of CypB reduced cell proliferation and survival in human glioblastoma multiforme cells in vitro and in vivo. We also found that treatment with small molecule inhibitors of cyclophilins, including the approved drug cyclosporine, greatly reduced the viability of glioblastoma multiforme cells. Mechanistically, depletion or pharmacologic inhibition of CypB caused hyperactivation of the oncogenic RAS–mitogen-activated protein kinase pathway, induction of cellular senescence signals, and death resulting from loss of MYC, mutant p53, Chk1, and Janus-activated kinase/STAT3 signaling. Elevated reactive oxygen species, ER expansion, and abnormal unfolded protein responses in CypB-depleted glioblastoma multiforme cells indicated that CypB alleviates oxidative and ER stresses and coordinates stress adaptation responses. Enhanced cell survival and sustained expression of multiple oncogenic proteins downstream of CypB may thus contribute to the poor outcome of glioblastoma multiforme tumors. Our findings link chaperone-mediated protein folding in the ER to mechanisms underlying oncogenic transformation, and they make CypB an attractive and immediately targetable molecule for glioblastoma multiforme therapy. Cancer Res; 74(2); 484–96. ©2013 AACR.
Data from TLR7 Promotes Tumor Progression, Chemotherapy Resistance, and Poor Clinical Outcomes in Non–Small Cell Lung Cancer
Authors: Chatterjee Saradiya , Crozet Lucile , Damotte Diane , Iribarren Kristina , Schramm Catherine , Alifano Marco , Lupo Audrey , Cherfils-Vicini Julien , Goc Jeremy , Katsahian Sandrine , Younes Mohammad , Dieu-Nosjean Marie Caroline , Fridman Wolf Herman , Sautès-Fridman Catherine , Cremer Isabelle
Published: March 2024

Abstract
Toll-like receptors (TLR) recognize pathogen molecules and danger-associated signals that stimulate inflammatory processes. TLRs have been studied mainly in antigen-presenting cells, where they exert important immune regulatory functions, but they are also expressed by epithelial tumor cells, where they have been implicated in tumor progression. In this study, we demonstrate that the injection of TLR7 agonist in NOD/SCID mice, in C57BL/6 wild-type, and TLR7-deficient mice grafted with lung adenocarcinoma tumor cells leads to increased tumor progression and chemotherapeutic resistance. In patients with non–small cell lung cancer, expression analyses revealed that high TLR7 expression was strongly associated with resistance to neoadjuvant chemotherapy and poor clinical outcomes. Our findings delineate a crucial role for TLR7 in lung cancer physiopathology. Cancer Res; 74(18); 5008–18. ©2014 AACR.
Data from LIMD2 Is a Small LIM-Only Protein Overexpressed in Metastatic Lesions That Regulates Cell Motility and Tumor Progression by Directly Binding to and Activating the Integrin-Linked Kinase
Authors: Peng Hongzhuang , Talebzadeh-Farrooji Mehdi , Osborne Michael J. , Prokop Jeremy W. , McDonald Paul C. , Karar Jayashree , Hou Zhaoyuan , He Mei , Kebebew Electron , Orntoft Torben , Herlyn Meenhard , Caton Andrew J. , Fredericks William , Malkowicz Bruce , Paterno Christopher S. , Carolin Alexandra S. , Speicher David W. , Skordalakes Emmanuel , Huang Qihong , Dedhar Shoukat , Borden Katherine L.B. , Rauscher Frank J.
Published: March 2024

Abstract
Proteins that communicate signals from the cytoskeleton to the nucleus are prime targets for effectors of metastasis as they often transduce signals regulating adhesion, motility, and invasiveness. LIM domain proteins shuttle between the cytoplasm and the nucleus, and bind to partners in both compartments, often coupling changes in gene expression to extracellular cues. In this work, we characterize LIMD2, a mechanistically undefined LIM-only protein originally found to be overexpressed in metastatic lesions but absent in the matched primary tumor. LIMD2 levels in fresh and archival tumors positively correlate with cell motility, metastatic potential, and grade, including bladder, melanoma, breast, and thyroid tumors. LIMD2 directly contributes to these cellular phenotypes as shown by overexpression, knockdown, and reconstitution experiments in cell culture models. The solution structure of LIMD2 that was determined using nuclear magnetic resonance revealed a classic LIM-domain structure that was highly related to LIM1 of PINCH1, a core component of the integrin-linked kinase–parvin–pinch complex. Structural and biochemical analyses revealed that LIMD2 bound directly to the kinase domain of integrin-linked kinase (ILK) near the active site and strongly activated ILK kinase activity. Cells that were null for ILK failed to respond to the induction of invasion by LIMD2. This strongly suggests that LIMD2 potentiates its biologic effects through direct interactions with ILK, a signal transduction pathway firmly linked to cell motility and invasion. In summary, LIMD2 is a new component of the signal transduction cascade that links integrin-mediated signaling to cell motility/metastatic behavior and may be a promising target for controlling tumor spread. Cancer Res; 74(5); 1390–403. ©2014 AACR.
Data from Vaccine-Mediated Immunotherapy Directed against a Transcription Factor Driving the Metastatic Process
Authors: Ardiani Andressa , Gameiro Sofia R. , Palena Claudia , Hamilton Duane H. , Kwilas Anna , King Thomas H. , Schlom Jeffrey , Hodge James W.
Published: March 2024

Abstract
Numerous reports have now demonstrated that the epithelial-to-mesenchymal transition (EMT) process is involved in solid tumor progression, metastasis, and drug resistance. Several transcription factors have been implicated as drivers of EMT and metastatic progression, including Twist. Overexpression of Twist has been shown to be associated with poor prognosis and drug resistance for many carcinomas and other tumor types. The role of Twist in experimental cancer metastases has been principally studied in the 4T1 mammary tumor model, where silencing of Twist in vitro has been shown to greatly reduce in vivo metastatic spread. Transcription factors such as Twist are generally believed to be “undruggable” because of their nuclear location and lack of a specific groove for tight binding of a small molecule inhibitor. An alternative approach to drug therapy targeting transcription factors driving the metastatic process is T-cell–mediated immunotherapy. A therapeutic vaccine platform that has been previously characterized consists of heat-killed recombinant Saccharomyces cerevisiae (yeast) capable of expressing tumor-associated antigen protein. We report here the construction and characterization of a recombinant yeast expressing the entire Twist protein, which is capable of inducing both CD8+ and CD4+ Twist-specific T-cell responses in vivo. Vaccination of mice reduced the size of primary transplanted 4T1 tumors and had an even greater antitumor effect on lung metastases of the same mice, which was dependent on Twist-specific CD8+ T cells. These studies provide the rationale for vaccine-induced T-cell–mediated therapy of transcription factors involved in driving the metastatic process. Cancer Res; 74(7); 1945–57. ©2014 AACR.
Data from Loss of Androgen Receptor Expression Promotes a Stem-like Cell Phenotype in Prostate Cancer through STAT3 Signaling
Authors: Schroeder Anne , Herrmann Andreas , Cherryholmes Gregory , Kowolik Claudia , Buettner Ralf , Pal Sumanta , Yu Hua , Müller-Newen Gerhard , Jove Richard
Published: March 2024

Abstract
Androgen receptor (AR) signaling is important for prostate cancer progression. However, androgen-deprivation and/or AR targeting-based therapies often lead to resistance. Here, we demonstrate that loss of AR expression results in STAT3 activation in prostate cancer cells. AR downregulation further leads to development of prostate cancer stem-like cells (CSC), which requires STAT3. In human prostate tumor tissues, elevated cancer stem-like cell markers coincide with those cells exhibiting high STAT3 activity and low AR expression. AR downregulation-induced STAT3 activation is mediated through increased interleukin (IL)-6 expression. Treating mice with soluble IL-6 receptor fusion protein or silencing STAT3 in tumor cells significantly reduced prostate tumor growth and CSCs. Together, these findings indicate an opposing role of AR and STAT3 in prostate CSC development. Cancer Res; 74(4); 1227–37. ©2013 AACR.
Data from Molecular Rules Governing De Novo Methylation in Cancer
Authors: Nejman Deborah , Straussman Ravid , Steinfeld Israel , Ruvolo Michael , Roberts Douglas , Yakhini Zohar , Cedar Howard
Published: March 2024

Abstract
De novo methylation of CpG islands is seen in many cancers, but the general rules governing this process are not known. By analyzing DNA from tumors, as well as normal tissues, and by utilizing a range of published data, we have identified a universal set of tumor targets, each with its own “coefficient” of methylation that is largely correlated with its inherent relative ability to recruit polycomb. This pattern is initially formed by a slow process of de novo methylation that occurs during aging and then undergoes expansion early in tumorigenesis, where we hypothesize that it may act as an inhibitor of development-associated gene activation. Cancer Res; 74(5); 1475–83. ©2014 AACR.
Data from Tumor-Infiltrating Myeloid Cells Activate Dll4/Notch/TGF-β Signaling to Drive Malignant Progression
Authors: Ohnuki Hidetaka , Jiang Kan , Wang Dunrui , Salvucci Ombretta , Kwak Hyeongil , Sánchez-Martín David , Maric Dragan , Tosato Giovanna
Published: March 2024

Abstract
Myeloid cells that orchestrate malignant progression in the tumor microenvironment offer targets for a generalized strategy to attack solid tumors. Through an analysis of tumor microenvironments, we explored an experimental model of lung cancer that uncovered a network of Dll4/Notch/TGF-β1 signals that links myeloid cells to cancer progression. Myeloid cells attracted to the tumor microenvironment by the tumor-derived cytokines CCL2 and M-CSF expressed increased levels of the Notch ligand Dll4, thereby activating Notch signaling in the tumor cells and amplifying tumor-intrinsic Notch activation. Heightened Dll4/Notch signaling in tumor cells magnified TGF-β–induced pSMAD2/3 signaling and was required to sustain TGF-β–induced tumor cell growth. Conversely, Notch blockade reduced TGF-β signaling and limited lung carcinoma tumor progression. Corroborating these findings, by interrogating RNAseq results from tumor and adjacent normal tissue in clinical specimens of human head and neck squamous carcinoma, we found evidence that TGF-β/Notch crosstalk contributed to progression. In summary, the myeloid cell-carcinoma signaling network we describe uncovers novel mechanistic links between the tumor microenvironment and tumor growth, highlighting new opportunities to target tumors where this network is active. Cancer Res; 74(7); 2038–49. ©2014 AACR.
Data from Netrin-1 Promotes Medulloblastoma Cell Invasiveness and Angiogenesis, and Demonstrates Elevated Expression in Tumor Tissue and Urine of Patients with Pediatric Medulloblastoma
Authors: Akino Tomoshige , Han Xuezhe , Nakayama Hironao , McNeish Brendan , Zurakowski David , Mammoto Akiko , Klagsbrun Michael , Smith Edward
Published: March 2024

Abstract
Invasion and dissemination of medulloblastoma within the central nervous system is the principal factor predicting medulloblastoma treatment failure and death. Netrin-1 is an axon guidance factor implicated in tumor and vascular biology, including in invasive behaviors. We found that exogenous netrin-1 stimulated invasion of human medulloblastoma cells and endothelial cells in contrast to VEGF-A, which promoted invasion of endothelial cells but not medulloblastoma cells. Furthermore, medulloblastoma cells expressed endogenous netrin-1 along with its receptors, neogenin and UNC5B. Blockades in endogenous netrin-1, neogenin, or UNC5B reduced medulloblastoma invasiveness. Neogenin blockade inhibited netrin-1–induced endothelial cells tube formation and recruitment of endothelial cells into Matrigel plugs, two hallmarks of angiogenesis. In patients with pediatric medulloblastoma, netrin-1 mRNA levels were increased 1.7-fold in medulloblastoma tumor specimens compared with control specimens from the same patient. Immunohistochemical analyses showed that netrin-1 was elevated in medulloblastoma tumors versus cerebellum controls. Notably, urinary levels of netrin-1 were 9-fold higher in patients with medulloblastoma compared with control individuals. Moreover, urinary netrin-1 levels were higher in patients with invasive medulloblastoma compared with patients with noninvasive medulloblastoma. Finally, we noted that urinary netrin-1 levels diminished after medulloblastoma resection in patients. Our results suggest netrin-1 is a candidate biomarker capable of detecting an invasive, disseminated phenotype in patients with medulloblastoma and predicting their disease status. Cancer Res; 74(14); 3716–26. ©2014 AACR.
Data from Maintaining Glycogen Synthase Kinase-3 Activity Is Critical for mTOR Kinase Inhibitors to Inhibit Cancer Cell Growth
Authors: Koo Junghui , Yue Ping , Gal Anthony A. , Khuri Fadlo R. , Sun Shi-Yong
Published: March 2024

Abstract
mTOR kinase inhibitors that target both mTORC1 and mTORC2 are being evaluated in cancer clinical trials. Here, we report that glycogen synthase kinase-3 (GSK3) is a critical determinant for the therapeutic response to this class of experimental drugs. Pharmacologic inhibition of GSK3 antagonized their suppressive effects on the growth of cancer cells similarly to genetic attenuation of GSK3. Conversely, expression of a constitutively activated form of GSK3β sensitized cancer cells to mTOR inhibition. Consistent with these findings, higher basal levels of GSK3 activity in a panel of human lung cancer cell lines correlated with more efficacious responses. Mechanistic investigations showed that mTOR kinase inhibitors reduced cyclin D1 levels in a GSK3β-dependent manner, independent of their effects on suppressing mTORC1 signaling and cap binding. Notably, selective inhibition of mTORC2 triggered proteasome-mediated cyclin D1 degradation, suggesting that mTORC2 blockade is responsible for GSK3-dependent reduction of cyclin D1. Silencing expression of the ubiquitin E3 ligase FBX4 rescued this reduction, implicating FBX4 in mediating this effect of mTOR inhibition. Together, our findings define a novel mechanism by which mTORC2 promotes cell growth, with potential implications for understanding the clinical action of mTOR kinase inhibitors. Cancer Res; 74(9); 2555–68. ©2014 AACR.
Data from Cysteine Catabolism: A Novel Metabolic Pathway Contributing to Glioblastoma Growth
Authors: Prabhu Antony , Sarcar Bhaswati , Kahali Soumen , Yuan Zhigang , Johnson Joseph J. , Adam Klaus-Peter , Kensicki Elizabeth , Chinnaiyan Prakash
Published: March 2024

Abstract
The relevance of cysteine metabolism in cancer has gained considerable interest in recent years, largely focusing on its role in generating the antioxidant glutathione. Through metabolomic profiling using a combination of high-throughput liquid and gas chromatography–based mass spectrometry on a total of 69 patient-derived glioma specimens, this report documents the discovery of a parallel pathway involving cysteine catabolism that results in the accumulation of cysteine sulfinic acid (CSA) in glioblastoma. These studies identified CSA to rank as one of the top metabolites differentiating glioblastoma from low-grade glioma. There was strong intratumoral concordance of CSA levels with expression of its biosynthetic enzyme cysteine dioxygenase 1 (CDO1). Studies designed to determine the biologic consequence of this metabolic pathway identified its capacity to inhibit oxidative phosphorylation in glioblastoma cells, which was determined by decreased cellular respiration, decreased ATP production, and increased mitochondrial membrane potential following pathway activation. CSA-induced attenuation of oxidative phosphorylation was attributed to inhibition of the regulatory enzyme pyruvate dehydrogenase. Studies performed in vivo abrogating the CDO1/CSA axis using a lentiviral-mediated short hairpin RNA approach resulted in significant tumor growth inhibition in a glioblastoma mouse model, supporting the potential for this metabolic pathway to serve as a therapeutic target. Collectively, we identified a novel, targetable metabolic pathway involving cysteine catabolism contributing to the growth of aggressive high-grade gliomas. These findings serve as a framework for future investigations designed to more comprehensively determine the clinical application of this metabolic pathway and its contributory role in tumorigenesis. Cancer Res; 74(3); 787–96. ©2013 AACR.
Data from Survival in Patients with High-Risk Prostate Cancer Is Predicted by miR-221, Which Regulates Proliferation, Apoptosis, and Invasion of Prostate Cancer Cells by Inhibiting IRF2 and SOCS3
Authors: Kneitz Burkhard , Krebs Markus , Kalogirou Charis , Schubert Maria , Joniau Steven , van Poppel Hein , Lerut Evelyne , Kneitz Susanne , Scholz Claus Jürgen , Ströbel Philipp , Gessler Manfred , Riedmiller Hubertus , Spahn Martin
Published: March 2024

Abstract
A lack of reliably informative biomarkers to distinguish indolent and lethal prostate cancer is one reason this disease is overtreated. miR-221 has been suggested as a biomarker in high-risk prostate cancer, but there is insufficient evidence of its potential utility. Here we report that miR-221 is an independent predictor for cancer-related death, extending and validating earlier findings. By mechanistic investigations we showed that miR-221 regulates cell growth, invasiveness, and apoptosis in prostate cancer at least partially via STAT1/STAT3-mediated activation of the JAK/STAT signaling pathway. miR-221 directly inhibits the expression of SOCS3 and IRF2, two oncogenes that negatively regulate this signaling pathway. miR-221 expression sensitized prostate cancer cells for IFN-γ–mediated growth inhibition. Our findings suggest that miR-221 offers a novel prognostic biomarker and therapeutic target in high-risk prostate cancer. Cancer Res; 74(9); 2591–603. ©2014 AACR.
Data from Targeting Akt3 Signaling in Triple-Negative Breast Cancer
Authors: Chin Y. Rebecca , Yoshida Taku , Marusyk Andriy , Beck Andrew H. , Polyak Kornelia , Toker Alex
Published: March 2024

Abstract
Triple-negative breast cancer (TNBC) is currently the only major breast tumor subtype without effective targeted therapy and, as a consequence, in general has a poor outcome. To identify new therapeutic targets in TNBC, we performed a short hairpin RNA (shRNA) screen for protein kinases commonly amplified and overexpressed in breast cancer. Using this approach, we identified AKT3 as a gene preferentially required for the growth of TNBCs. Downregulation of Akt3 significantly inhibits the growth of TNBC lines in three-dimensional (3D) spheroid cultures and in mouse xenograft models, whereas loss of Akt1 or Akt2 have more modest effects. Akt3 silencing markedly upregulates the p27 cell-cycle inhibitor and this is critical for the ability of Akt3 to inhibit spheroid growth. In contrast with Akt1, Akt3 silencing results in only a minor enhancement of migration and does not promote invasion. Depletion of Akt3 in TNBC sensitizes cells to the pan-Akt inhibitor GSK690693. These results imply that Akt3 has a specific function in TNBCs; thus, its therapeutic targeting may provide a new treatment option for this tumor subtype. Cancer Res; 74(3); 964–73. ©2013 AACR.
Data from Identification of Alternative Splicing Events Regulated by the Oncogenic Factor SRSF1 in Lung Cancer
Authors: de Miguel Fernando J. , Sharma Ravi D. , Pajares María J. , Montuenga Luis M. , Rubio Angel , Pio Ruben
Published: March 2024

Abstract
Abnormal alternative splicing has been associated with cancer. Genome-wide microarrays can be used to detect differential splicing events. In this study, we have developed ExonPointer, an algorithm that uses data from exon and junction probes to identify annotated cassette exons. We used the algorithm to profile differential splicing events in lung adenocarcinoma A549 cells after downregulation of the oncogenic serine/arginine-rich splicing factor 1 (SRSF1). Data were generated using two different microarray platforms. The PCR-based validation rate of the top 20 ranked genes was 60% and 100%. Functional enrichment analyses found a substantial number of splicing events in genes related to RNA metabolism. These analyses also identified genes associated with cancer and developmental and hereditary disorders, as well as biologic processes such as cell division, apoptosis, and proliferation. Most of the top 20 ranked genes were validated in other adenocarcinoma and squamous cell lung cancer cells, with validation rates of 80% to 95% and 70% to 75%, respectively. Moreover, the analysis allowed us to identify four genes, ATP11C, IQCB1, TUBD1, and proline-rich coiled-coil 2C (PRRC2C), with a significantly different pattern of alternative splicing in primary non–small cell lung tumors compared with normal lung tissue. In the case of PRRC2C, SRSF1 downregulation led to the skipping of an exon overexpressed in primary lung tumors. Specific siRNA downregulation of the exon-containing variant significantly reduced cell growth. In conclusion, using a novel analytical tool, we have identified new splicing events regulated by the oncogenic splicing factor SRSF1 in lung cancer. Cancer Res; 74(4); 1105–15. ©2013 AACR.