bluuebunny/crossref_metadata_2025 huggingface dataset:
Data from Expression and Immunotherapeutic Targeting of the SSX Family of Cancer–Testis Antigens in Prostate Cancer
Authors: Smith Heath A. , Cronk Robert J. , Lang Joshua M. , McNeel Douglas G.
Published: March 2024

Abstract
Recent U.S. Food and Drug Administration approval of the first immunotherapy for prostate cancer encourages efforts to improve immune targeting of this disease. The synovial sarcoma X chromosome breakpoint (SSX) proteins comprise a set of cancer–testis antigens that are upregulated in MHC class I–deficient germline cells and in various types of advanced cancers with a poor prognosis. Humoral and cell-mediated immune responses to the SSX family member SSX2 can arise spontaneously in prostate cancer patients. Thus, SSX2 and other proteins of the SSX family may offer useful targets for tumor immunotherapy. In this study, we evaluated the expression of SSX family members in prostate cancer cell lines and tumor biopsies to identify which members might be most appropriate for immune targeting. We found that SSX2 was expressed most frequently in prostate cell lines, but that SSX1 and SSX5 were also expressed after treatment with the DNA demethylating agent 5-aza-2′-deoxycytidine. Immunohistochemical analysis of microarrayed tissue biopsies confirmed a differential level of SSX protein expression in human prostate cancers. Notably, SSX expression in patient tumor samples was restricted to metastatic lesions (5/22; 23%) and no expression was detected in primary prostate tumors examined (0/73; P < 0.001). We determined that cross-reactive immune responses to a dominant HLA-A2–specific SSX epitope (p103-111) could be elicited by immunization of A2/DR1 transgenic mice with SSX vaccines. Our findings suggest that multiple SSX family members are expressed in metastatic prostate cancers which are amenable to simultaneous targeting. Cancer Res; 71(21); 6785–95. ©2011 AACR.
Data from The First Tianjin, China Forum on Tumor Microenvironment
Authors: Keller Evan T. , Li Lu-Yuan
Published: March 2024

Abstract
Although it is well recognized that the tumor microenvironment plays a key role in regulating tumor progression, the mechanisms through which this occurs need to be defined. Current international research activities toward defining the role of the tumor microenvironment in cancer progression were the subject of the first Tianjin Forum on Tumor Microenvironment held at Nankai University in Tianjin, China, July 2 to 4, 2010. The importance of variety of processes, such as inflammation and angiogenesis, in the role of tumor progression was described for multiple tumor types including breast, prostate, and hepatic cancers, as well as the process of bone metastasis. Identification of novel signaling pathways that impact both angiogenesis and bone remodeling were presented. Several themes emerged from this meeting, such as: (i) tumor cells modify the microenvironment to enhance their own survival and progression; (ii) targeting host factors, in addition to targeting tumor cells, will have important therapeutic effects; and (iii) host cells distribution within the tumor has both prognostic and therapeutic significance. Several priorities for future research were defined including use of a systems biology approach to define the role of host factors in tumor progression, to define the importance of targeting both arms of the bone remodeling process for therapy of bone metastasis, and to determine how different cell subsets contribute to microenvironment-mediated regulation of tumor progression. Cancer Res; 71(2); 310–3. ©2011 AACR.
Data from Ror1 Is a Pseudokinase That Is Crucial for Met-Driven Tumorigenesis
Authors: Gentile Alessandra , Lazzari Luca , Benvenuti Silvia , Trusolino Livio , Comoglio Paolo M.
Published: March 2024

Abstract
The human kinome includes Ror1, a poorly characterized orphan receptor. Here we report the findings of an investigation of Ror1 contributions to cancer, undertaken through an integrated screening of 43 cancer cell lines where we measured protein expression, tyrosine phosphorylation, and growth response following RNAi-mediated Ror1 suppression. Ror1 was expressed in approximately 75% of the cancer cell lines without apparent histotype distribution. Gastric carcinoma cells (HS746T) and non–small cell lung carcinoma cells (NCI-H1993) exhibited high levels of Ror1 tyrosine phosphorylation, and Ror1 suppression caused growth inhibition. Biochemical assays revealed unexpectedly that Ror1 is a pseudokinase that is devoid of catalytic activity. Intriguingly, the two cell lines featuring tyrosine-phosphorylated Ror1 both exhibited amplification and activation of the Met oncogene. Ror1 phosphorylation was abrogated by Met inhibition, indicating Met-dependent transphosphorylation of Ror1. Conversely, Ror1 was not transphosphorylated by other constitutively active tyrosine kinases, including EGFR and ErbB2. Constitutive silencing of Ror1 in HS746T and NCI-H1993 carcinoma cells impaired proliferation in vitro and induced a dramatic inhibition of tumorigenesis in vivo. Together, our findings suggest a critical role for Ror1 in malignant phenotypes sustained by the Met oncogene. Cancer Res; 71(8); 3132–41. ©2011 AACR.
Data from Select Heterozygous Keap1 Mutations Have a Dominant-Negative Effect on Wild-Type Keap1 In Vivo
Authors: Suzuki Takafumi , Maher Jonathan , Yamamoto Masayuki
Published: March 2024

Abstract
Under homeostatic conditions, Keap1 constitutively mediates the proteasomal degradation Nrf2. However, tertiary changes in Keap1 in response to the cellular environment allow for liberation of Nrf2 to transcriptionally regulate downstream cytoprotective genes that aid in cell survival. KEAP1/NRF2 somatic mutations causing constitutive NRF2 activation have been estimated to occur in approximately 25% of human lung tumors, with similar rates believed to exist in other tissue subtypes. As the stoichiometry between Keap1 and Nrf2 is 2:1, we hypothesized that heterozygous Keap1 mutations could suppress wild-type Keap1 (Keap1WT) activity by functioning as a dominant-negative protein through heterodimerization of mutant Keap1 (Keap1mutant) with Keap1WT. When Keap1G430C or Keap1G364C mutants were expressed in lieu of Keap1WT, premature juvenile mortality was observed. To test the hypothesis of a dominant-negative effect, Keap1-null mice were engineered to coexpress both Keap1WT and Keap1G430C transgenes, a phenotype analogous to that previously observed from a human lung tumor. These mice were viable, but phenotypically displayed hyperactivation of downstream Nrf2 target genes and moderate esophageal hyperkeratosis. Similar to the transgenic mouse Keap1G430C mutant, Keap1C273&288A substitutions also diminished Keap1WT activity in vivo. To further delineate involvement of the dominant-negative heterodimer, transgenic mice with a deletion or strategic mutation in Broad-complex, Tramtrack and Bric-a-Brac (BTB) domain that disallowed Keap1 dimerization were generated in the presence of Keap1WT, and failed to induce the dominant-negative effect in vivo. These results thus demonstrate that sequestration of Keap1WT into a Keap1mutant–Keap1WT heterodimer leads to a dominant-negative effect in vivo and gives rise to Nrf2 activation. Cancer Res; 71(5); 1700–9. ©2010 AACR.
Data from HIF-1α Confers Aggressive Malignant Traits on Human Tumor Cells Independent of Its Canonical Transcriptional Function
Authors: Yoo Young-Gun , Christensen Jared , Huang L. Eric
Published: March 2024

Abstract
Hypoxia is known to favor tumor survival and progression. Numerous studies have shown that hypoxia-inducible factor 1α (HIF-1α), an oxygen-sensitive transcription factor, is overexpressed in various types of human cancers and upregulates a battery of hypoxia-responsive genes for the growth and survival of cancer cells. Although tumor progression involves the acquisition of genetic and/or epigenetic changes that confer additional malignant traits, the underlying mechanisms of these changes remain obscure. We recently identified an alternative mechanism of HIF-1α function by which HIF-1α suppresses DNA repair by counteracting c-Myc transcriptional activity that maintains gene expression. Here, we show that this HIF-α–c-Myc pathway plays an essential role in mediating hypoxic effects on malignant progression via genetic alterations, resulting in the formation of malignant tumors with aggressive local invasion and epithelial–mesenchymal transition. We show an absolute requirement of the HIF-α–c-Myc pathway for malignant progression, whereas the canonical transcription function of HIF-1α alone is insufficient and seemingly dispensable. This study indicates that HIF-1α induction of genetic alteration is the underlying cause of tumor progression, especially by the hypoxic microenvironment. Cancer Res; 71(4); 1244–52. ©2011 AACR.
Data from Noncytotoxic Differentiation Treatment of Renal Cell Cancer
Authors: Negrotto Soledad , Hu Zhenbo , Alcazar Oscar , Ng Kwok Peng , Triozzi Pierre , Lindner Daniel , Rini Brian , Saunthararajah Yogen
Published: March 2024

Abstract
Current drug therapy for metastatic renal cell cancer (RCC) results in temporary disease control but not cure, necessitating continued investigation into alternative mechanistic approaches. Drugs that inhibit chromatin-modifying enzymes involved in transcription repression (chromatin-relaxing drugs) could have a role, by inducing apoptosis and/or through differentiation pathways. At low doses, the cytosine analogue decitabine (DAC) can be used to deplete DNA methyl-transferase 1 (DNMT1), modify chromatin, and alter differentiation without causing apoptosis (cytotoxicity). Noncytotoxic regimens of DAC were evaluated for in vitro and in vivo efficacy against RCC cell lines, including a p53-mutated RCC cell line developed from a patient with treatment-refractory metastatic RCC. The cell division–permissive mechanism of action—absence of early apoptosis or DNA damage, increase in expression of HNF4α (hepatocyte nuclear factor 4α), a key driver associated with the mesenchymal to epithelial transition, decrease in mesenchymal marker expression, increase in epithelial marker expression, and late increase in cyclin-dependent kinase inhibitor CDKN1B (p27) protein—was consistent with differentiation-mediated cell-cycle exit. In vivo blood counts and animal weights were consistent with minimal toxicity of therapy. The distinctive mechanism of action of a dose and schedule of DAC designed for noncytotoxic depletion of DNMT1 suggests a potential role in treating RCC. Cancer Res; 71(4); 1431–41. ©2011 AACR.
Data from Apoptosis Inhibitor ARC Promotes Breast Tumorigenesis, Metastasis, and Chemoresistance
Authors: Medina-Ramirez Christina M. , Goswami Sumanta , Smirnova Tatiana , Bamira Daniel , Benson Benjamin , Ferrick Neal , Segall Jeffrey , Pollard Jeffrey W. , Kitsis Richard N.
Published: March 2024

Abstract
Apoptosis repressor with caspase recruitment domain (ARC) inhibits both death receptor- and mitochondrial/ER-mediated pathways of apoptosis. Although expressed mainly in terminally differentiated cells, ARC is markedly upregulated in a variety of human cancers, where its potential contributions have not yet been defined. In this study, we provide evidence of multiple critical pathophysiologic functions for ARC in breast carcinogenesis. In the polyoma middle T-antigen (PyMT) transgenic mouse model of breast cancer, in which endogenous ARC is strongly upregulated, deletion of the ARC-encoding gene nol3 decreased primary tumor burden without affecting tumor onset or multiplicity. More notably, ARC deficiency also limited tumor cell invasion and the number of circulating cancer cells, markedly reducing the number of lung metastases. Conversely, ectopic overexpression of ARC in a PyMT-derived metastatic breast cancer cell line increased invasion in vitro and lung metastasis in vivo. We confirmed these results in a humanized orthotopic model based on MDA-MB-231-derived LM2 metastatic breast cancer cells, in which RNAi-mediated knockdown of ARC levels was shown to reduce tumor volume, local invasion, and lung metastases. Lastly, we found that endogenous levels of ARC conferred chemoresistance in primary tumors and invading cell populations. Our results establish that ARC promotes breast carcinogenesis by driving primary tumor growth, invasion, and metastasis as well as by promoting chemoresistance in invasive cells. Cancer Res; 71(24); 7705–15. ©2011 AACR.
Data from Differentiation of NUT Midline Carcinoma by Epigenomic Reprogramming
Authors: Schwartz Brian E. , Hofer Matthias D. , Lemieux Madeleine E. , Bauer Daniel E. , Cameron Michael J. , West Nathan H. , Agoston Elin S. , Reynoird Nicolas , Khochbin Saadi , Ince Tan A. , Christie Amanda , Janeway Katherine A. , Vargas Sara O. , Perez-Atayde Antonio R. , Aster Jon C. , Sallan Stephen E. , Kung Andrew L. , Bradner James E. , French Christopher A.
Published: March 2024

Abstract
NUT midline carcinoma (NMC) is a lethal pediatric tumor defined by the presence of BRD-NUT fusion proteins that arrest differentiation. Here we explore the mechanisms underlying the ability of BRD4-NUT to prevent squamous differentiation. In both gain-of and loss-of-expression assays, we find that expression of BRD4-NUT is associated with globally decreased histone acetylation and transcriptional repression. Bulk chromatin acetylation can be restored by treatment of NMC cells with histone deacetylase inhibitors (HDACi), engaging a program of squamous differentiation and arrested growth in vitro that closely mimics the effects of siRNA-mediated attenuation of BRD4-NUT expression. The potential therapeutic utility of HDACi differentiation therapy was established in three different NMC xenograft models, where it produced significant growth inhibition and a survival benefit. Based on these results and translational studies performed with patient-derived primary tumor cells, a child with NMC was treated with the FDA-approved HDAC inhibitor, vorinostat. An objective response was obtained after five weeks of therapy, as determined by positron emission tomography. These findings provide preclinical support for trials of HDACi in patients with NMC. Cancer Res; 71(7); 2686–96. ©2011 AACR.
Data from Cancer Causes Cardiac Atrophy and Autophagy in a Sexually Dimorphic Manner
Authors: Cosper Pippa F. , Leinwand Leslie A.
Published: March 2024

Abstract
Approximately one-third of cancer deaths are caused by cachexia, a severe form of skeletal muscle and adipose tissue wasting that affects men more than women. The heart also undergoes atrophy in cancer patients, but the mechanisms and the basis for apparent sex differences are unclear. In a mouse colon-adenocarcinoma model, cancer causes a loss of cardiac mass due to a decrease in cardiac myocyte size that is associated with reduced levels of all sarcomeric proteins. Unlike skeletal muscle cachexia, atrophic hearts do not upregulate the ubiquitin-proteasome system or its activity but increase autophagy. Thus, cancer causes cardiac atrophy by a mechanism distinct from that in skeletal muscle. Male tumor-bearing mice have a more severe phenotype than females, including greater cardiac mass loss and mortality, a more robust pro-inflammatory response to the tumor, and greater cardiac autophagy. In females, estrogen protects against cancer-induced cardiac atrophy and body weight loss by signaling through its receptor. Sex differences in cardiac atrophy need to be considered during the treatment of patients suffering from chemotherapy-induced cardiomyopathy to prevent exacerbation of cardiac dysfunction. Cancer Res; 71(5); 1710–20. ©2010 AACR.
Data from Tyrosine Isomers Mediate the Classical Phenomenon of Concomitant Tumor Resistance
Authors: Ruggiero Raúl A. , Bruzzo Juan , Chiarella Paula , di Gianni Pedro , Isturiz Martín A. , Linskens Susana , Speziale Norma , Meiss Roberto P. , Bustuoabad Oscar D. , Pasqualini Christiane D.
Published: March 2024

Abstract
Concomitant tumor resistance (CR) is a phenomenon originally described in 1906 in which a tumor-bearing host is resistant to the growth of secondary tumor implants and metastasis. Although recent studies have indicated that T-cell–dependent processes mediate CR in hosts bearing immunogenic small tumors, manifestations of CR induced by immunogenic and nonimmunogenic large tumors have been associated with an elusive serum factor. In this study, we identify this serum factor as tyrosine in its meta and ortho isoforms. In three different murine models of cancer that generate CR, both meta-tyrosine and ortho-tyrosine inhibited tumor growth. In addition, we showed that both isoforms of tyrosine blocked metastasis in a fourth model that does not generate CR but is sensitive to CR induced by other tumors. Mechanistic studies showed that the antitumor effects of the tyrosine isoforms were mediated, in part, by early inhibition of mitogen-activated protein/extracellular signal-regulated kinase pathway and inactivation of STAT3, potentially driving tumor cells into a state of dormancy. By revealing a molecular basis for the classical phenomenon of CR, our findings may stimulate new generalized approaches to limit the development of metastases that arise after resection of primary tumors, an issue of pivotal importance to oncologists and their patients. Cancer Res; 71(22); 7113–24. ©2011 AACR.
Data from TGF-β Promotion of Gli2-Induced Expression of Parathyroid Hormone-Related Protein, an Important Osteolytic Factor in Bone Metastasis, Is Independent of Canonical Hedgehog Signaling
Authors: Johnson Rachelle W. , Nguyen Mai P. , Padalecki Susan S. , Grubbs Barry G. , Merkel Alyssa R. , Oyajobi Babatunde O. , Matrisian Lynn M. , Mundy Gregory R. , Sterling Julie A.
Published: March 2024

Abstract
Breast cancer frequently metastasizes to bone, in which tumor cells receive signals from the bone marrow microenvironment. One relevant factor is TGF-β, which upregulates expression of the Hedgehog (Hh) signaling molecule, Gli2, which in turn increases secretion of important osteolytic factors such as parathyroid hormone–related protein (PTHrP). PTHrP inhibition can prevent tumor-induced bone destruction, whereas Gli2 overexpression in tumor cells can promote osteolysis. In this study, we tested the hypothesis that Hh inhibition in bone metastatic breast cancer would decrease PTHrP expression and therefore osteolytic bone destruction. However, when mice engrafted with human MDA-MB-231 breast cancer cells were treated with the Hh receptor antagonist cyclopamine, we observed no effect on tumor burden or bone destruction. In vitro analyses revealed that osteolytic tumor cells lack expression of the Hh receptor, Smoothened, suggesting an Hh-independent mechanism of Gli2 regulation. Blocking Gli signaling in metastatic breast cancer cells with a Gli2-repressor gene (Gli2-rep) reduced endogenous and TGF-β–stimulated PTHrP mRNA expression, but did not alter tumor cell proliferation. Furthermore, mice inoculated with Gli2-Rep–expressing cells exhibited a decrease in osteolysis, suggesting that Gli2 inhibition may block TGF-β propagation of a vicious osteolytic cycle in this MDA-MB-231 model of bone metastasis. Accordingly, in the absence of TGF-β signaling, Gli2 expression was downregulated in cells, whereas enforced overexpression of Gli2 restored PTHrP activity. Taken together, our findings suggest that Gli2 is required for TGF-β to stimulate PTHrP expression and that blocking Hh-independent Gli2 activity will inhibit tumor-induced bone destruction. Cancer Res; 71(3); 822–31. ©2010 AACR.
Data from Cyclin D1 Inhibits Mitochondrial Activity in B Cells
Authors: Tchakarska Guergana , Roussel Mikel , Troussard Xavier , Sola Brigitte
Published: March 2024

Abstract
Cyclin D1 is a cell cycle regulatory protein that acts at the G1-S transition, following its binding to and activation by the cyclin-dependent kinases 4 or 6. Cyclin D1 is absent from the entire B-cell lineage but is present in a large percentage of 2 types of malignant B-cell hemopathy—mantle cell lymphoma and multiple myeloma— suggesting a major role of this protein in the malignancy process. We show here, in an experimental model of cyclin D1 fusion protein transduction in mature B cells, that, cyclin D1 inhibits total mitochondrial activity. Cyclin D1 is localized at the outer mitochondrial membrane, bound to a voltage-dependent anion channel through its central domain, and it competes with hexokinase 2 for binding to this channel. The bound cyclin D1 decreases the supply of ADP, ATP, and metabolites, thereby reducing energy production. This function of cyclin D1 was also reported by others in normal and transformed mammary epithelial cells, suggesting that it may be ubiquitous. Cancer Res; 71(5); 1690–9. ©2011 AACR.
Data from Functional EGFR Germline Polymorphisms May Confer Risk for EGFR Somatic Mutations in Non–Small Cell Lung Cancer, with a Predominant Effect on Exon 19 Microdeletions
Authors: Liu Wanqing , He Lijun , Ramírez Jacqueline , Krishnaswamy Soundararajan , Kanteti Rajani , Wang Yi-Ching , Salgia Ravi , Ratain Mark J.
Published: March 2024

Abstract
Somatic mutations in the EGFR tyrosine kinase domain play a critical role in the development and treatment of non–small cell lung cancer (NSCLC). Strong genetic influence on susceptibility to these mutations has been suggested. To identify the genetic factors conferring risk for the EGFR tyrosine kinase mutations in NSCLC, a case–control study was conducted in 141 Taiwanese NSCLC patients by focusing on three functional polymorphisms in the EGFR gene [−216G/T, intron 1 (CA)n, and R497K]. Allelic imbalance of the EGFR −216G/T polymorphism was also tested in the heterozygous patients and in the NCI-60 cancer cell lines to further verify its function. We found that the frequencies of the alleles −216T and CA-19 are significantly higher in the patients with any mutation (P = 0.032 and 0.01, respectively), in particular in those with exon 19 microdeletions (P = 0.006 and 0.033, respectively), but not in the patients with L858R mutation. The −216T allele is favored to be amplified in both tumor DNA of lung cancer patients and cancer cell lines. We conclude that the local haplotype structures across the EGFR gene may favor the development of cellular malignancies and thus significantly confer risk to the occurrence of EGFR mutations in NSCLC, particularly the exon 19 microdeletions. Cancer Res; 71(7); 2423–7. ©2011 AACR.
Data from The RASSF3 Candidate Tumor Suppressor Induces Apoptosis and G1–S Cell-Cycle Arrest via p53
Authors: Kudo Takumi , Ikeda Mitsunobu , Nishikawa Misa , Yang Zeyu , Ohno Kikuo , Nakagawa Kentaro , Hata Yutaka
Published: March 2024

Abstract
RASSF3 is the smallest member of the RASSF family of proteins that function as tumor suppressors. Unlike other members of this important family, the mechanisms through which RASSF3 suppresses tumor formation remain unknown. Here, we show that RASSF3 expression induces p53-dependent apoptosis and its depletion attenuates DNA damage–induced apoptosis. We found that RASSF3-induced apoptosis depended upon p53 expression. Exogenous expression of RASSF3 induced G1–S arrest, which was also p53 dependent. In contrast, loss of RASSF3 promoted cell-cycle progression, abrogated UVB- and VP-16–induced G1–S arrest, decreased p53 protein and target gene expression, and prevented DNA repair. RASSF3 was shown to directly interact with and facilitate the ubiquitination of MDM2, the E3 ligase that targets p53 for degradation, thereby increasing p53 stabilization. Together, our findings show the tumor suppressor activity of RASSF3, which occurs through p53 stabilization and regulation of apoptosis and the cell cycle. Cancer Res; 72(11); 2901–11. ©2012 AACR.
Data from A Zebrafish Model to Study and Therapeutically Manipulate Hypoxia Signaling in Tumorigenesis
Authors: Santhakumar Kirankumar , Judson Emma C. , Elks Philip M. , McKee Sarah , Elworthy Stone , van Rooijen Ellen , Walmsley Sarah S. , Renshaw Stephen A. , Cross Simon S. , van Eeden Fredericus J.M.
Published: March 2024

Abstract
Hypoxic signaling is a central modulator of cellular physiology in cancer. Core members of oxygen-sensing pathway including the von Hippel-Lindau tumor suppressor protein (pVHL) and the hypoxia inducible factor (HIF) transcription factors have been intensively studied, but improved organismal models might speed advances for both pathobiologic understanding and therapeutic modulation. To study HIF signaling during tumorigenesis and development in zebrafish, we developed a unique in vivo reporter for hypoxia, expressing EGFP driven by prolyl hydroxylase 3 (phd3) promoter/regulatory elements. Modulation of HIF pathway in Tg(phd3::EGFP) embryos showed a specific role for hypoxic signaling in the transgene activation. Zebrafish vhl mutants display a systemic hypoxia response, reflected by strong and ubiquitous transgene expression. In contrast to human VHL patients, heterozygous Vhl mice and vhl zebrafish are not predisposed to cancer. However, upon exposure to dimethylbenzanthracene (DMBA), the vhl heterozygous fish showed an increase in the occurrence of hepatic and intestinal tumors, a subset of which exhibited strong transgene expression, suggesting loss of Vhl function in these tumor cells. Compared with control fish, DMBA-treated vhl heterozygous fish also showed an increase in proliferating cell nuclear antigen-positive renal tubules. Taken together, our findings establish Vhl as a genuine tumor suppressor in zebrafish and offer this model as a tool to noninvasively study VHL and HIF signaling during tumorigenesis and development. Cancer Res; 72(16); 4017–27. ©2012 AACR.
Data from Systemic Delivery of Salmonella typhimurium Transformed with IDO shRNA Enhances Intratumoral Vector Colonization and Suppresses Tumor Growth
Authors: Blache Céline A. , Manuel Edwin R. , Kaltcheva Teodora I. , Wong Andrea N. , Ellenhorn Joshua D.I. , Blazar Bruce R. , Diamond Don J.
Published: March 2024

Abstract
Generating antitumor responses through the inhibition of tumor-derived immune suppression represents a promising strategy in the development of cancer immunotherapeutics. Here, we present a strategy incorporating delivery of the bacterium Salmonella typhimurium (ST), naturally tropic for the hypoxic tumor environment, transformed with a small hairpin RNA (shRNA) plasmid against the immunosuppressive molecule indoleamine 2,3-dioxygenase 1 (shIDO). When systemically delivered into mice, shIDO silences host IDO expression and leads to massive intratumoral cell death that is associated with significant tumor infiltration by polymorphonuclear neutrophils (PMN). shIDO-ST treatment causes tumor cell death independently of host IDO and adaptive immunity, which may have important implications for use in immunosuppressed patients with cancer. Furthermore, shIDO-ST treatment increases reactive oxygen species (ROS) produced by infiltrating PMNs and, conversely, PMN immunodepletion abrogates tumor control. Silencing of host IDO significantly enhances S. typhimurium colonization, suggesting that IDO expression within the tumor controls the immune response to S. typhimurium. In summary, we present a novel approach to cancer treatment that involves the specific silencing of tumor-derived IDO that allows for the recruitment of ROS-producing PMNs, which may act primarily to clear S. typhimurium infection, but in the process also induces apoptosis of surrounding tumor tissue resulting in a vigorous antitumor effect. Cancer Res; 72(24); 6447–56. ©2012 AACR.
Data from Integrin α5β1 Plays a Critical Role in Resistance to Temozolomide by Interfering with the p53 Pathway in High-Grade Glioma
Authors: Janouskova Hana , Maglott Anne , Leger David Y. , Bossert Catherine , Noulet Fanny , Guerin Eric , Guenot Dominique , Pinel Sophie , Chastagner Pascal , Plenat François , Entz-Werle Natacha , Lehmann-Che Jacqueline , Godet Julien , Martin Sophie , Teisinger Jan , Dontenwill Monique
Published: March 2024

Abstract
Integrins play a role in the resistance of advanced cancers to radiotherapy and chemotherapy. In this study, we show that high expression of the α5 integrin subunit compromises temozolomide-induced tumor suppressor p53 activity in human glioblastoma cells. We found that depletion of the α5 integrin subunit increased p53 activity and temozolomide sensitivity. However, when cells were treated with the p53 activator nutlin-3a, the protective effect of α5 integrin on p53 activation and cell survival was lost. In a functional p53 background, nutlin-3a downregulated the α5 integrin subunit, thereby increasing the cytotoxic effect of temozolomide. Clinically, α5β1 integrin expression was associated with a more aggressive phenotype in brain tumors, and high α5 integrin gene expression was associated with decreased survival of patients with high-grade glioma. Taken together, our findings indicate that negative cross-talk between α5β1 integrin and p53 supports glioma resistance to temozolomide, providing preclinical proof-of-concept that α5β1 integrin represents a therapeutic target for high-grade brain tumors. Direct activation of p53 may remain a therapeutic option in the subset of patients with high-grade gliomas that express both functional p53 and a high level of α5β1 integrin. Cancer Res; 72(14); 3463–70. ©2012 AACR.
Data from The Vitamin E Analogue α-TEA Stimulates Tumor Autophagy and Enhances Antigen Cross-Presentation
Authors: Li Yuhuan , Hahn Tobias , Garrison Kendra , Cui Zhi-Hua , Thorburn Andrew , Thorburn Jacqueline , Hu Hong-Ming , Akporiaye Emmanuel T.
Published: March 2024

Abstract
The semisynthetic vitamin E derivative alpha-tocopheryloxyacetic acid (α-TEA) induces tumor cell apoptosis and may offer a simple adjuvant supplement for cancer therapy if its mechanisms can be better understood. Here we report that α-TEA also triggers tumor cell autophagy and that it improves cross-presentation of tumor antigens to the immune system. α-TEA stimulated both apoptosis and autophagy in murine mammary and lung cancer cells and inhibition of caspase-dependent apoptosis enhanced α-TEA–induced autophagy. Cell exposure to α-TEA generated double-membrane–bound vesicles indicative of autophagosomes, which efficiently cross-primed antigen-specific CD8+ T cells. Notably, vaccination with dendritic cells pulsed with α-TEA–generated autophagosomes reduced lung metastases and increased the survival of tumor-bearing mice. Taken together, our findings suggest that both autophagy and apoptosis signaling programs are activated during α-TEA–induced tumor cell killing. We suggest that the ability of α-TEA to stimulate autophagy and enhance cross-priming of CD8+ T cells might be exploited as an adjuvant strategy to improve stimulation of antitumor immune responses. Cancer Res; 72(14); 3535–45. ©2012 AACR.
Data from FRMD4A Upregulation in Human Squamous Cell Carcinoma Promotes Tumor Growth and Metastasis and Is Associated with Poor Prognosis
Authors: Goldie Stephen J. , Mulder Klaas W. , Tan David Wei-Min , Lyons Scott K. , Sims Andrew H. , Watt Fiona M.
Published: March 2024

Abstract
New therapeutic strategies are needed to improve treatment of head and neck squamous cell carcinoma (HNSCC), an aggressive tumor with poor survival rates. FRMD4A is a human epidermal stem cell marker implicated previously in epithelial polarity that is upregulated in SCC cells. Here, we report that FRMD4A upregulation occurs in primary human HNSCCs where high expression levels correlate with increased risks of relapse. FRMD4A silencing decreased growth and metastasis of human SCC xenografts in skin and tongue, reduced SCC proliferation and intercellular adhesion, and stimulated caspase-3 activity and expression of terminal differentiation markers. Notably, FRMD4A attenuation caused nuclear accumulation of YAP, suggesting a potential role for FRMD4A in Hippo signaling. Treatment with the HSP90 inhibitor 17-DMAG or ligation of CD44 with hyaluronan caused nuclear depletion of FRMD4A, nuclear accumulation of YAP and reduced SCC growth and metastasis. Together, our findings suggest FRMD4A as a novel candidate therapeutic target in HNSCC based on the key role in metastatic growth we have identified. Cancer Res; 72(13); 3424–36. ©2012 AACR.
Data from 3′-UTR and Functional Secretor Haplotypes in Mannose-Binding Lectin 2 Are Associated with Increased Colon Cancer Risk in African Americans
Authors: Zanetti Krista A. , Haznadar Majda , Welsh Judith A. , Robles Ana I. , Ryan Bríd M. , McClary Andrew C. , Bowman Elise D. , Goodman Julie E. , Bernig Toralf , Chanock Stephen J. , Harris Curtis C.
Published: March 2024

Abstract
Because chronic intestinal inflammation is a risk factor for colorectal cancer, we hypothesized that genetic variants of inflammatory mediators, such as mannose-binding lectin 2 (MBL2), are associated with colon cancer susceptibility. Here, we report the association of 24 MBL2 single-nucleotide polymorphisms (SNP) and corresponding haplotypes with colon cancer risk in a case–control study. Four SNPs in the 3′-untranslated region (UTR) of the gene (rs10082466, rs2120132, rs2099902, and rs10450310) were associated with an increased risk of colon cancer in African Americans. ORs for homozygous variants versus wild-type ranged from 3.17 [95% confidence interval (CI), 1.57–6.40] to 4.51 (95% CI, 1.94–10.50), whereas the 3′-UTR region haplotype consisting of these four variants had an OR of 2.10 (95% CI, 1.42–3.12). The C allele of rs10082466 exhibited a binding affinity of miR-27a and this allele was associated with both lower MBL plasma levels and activity. We found that 5′ secretor haplotypes known to correlate with moderate and low MBL serum levels exhibited associations with increased risk of colon cancer in African Americans, specifically as driven by two haplotypes, LYPA and LYQC, relative to the referent HYPA haplotype (LYPA: OR, 2.60; 95% CI, 1.33–5.08 and LYQC: OR, 2.28; 95% CI, 1.20–4.30). Similar associations were not observed in Caucasians. Together, our results support the hypothesis that genetic variations in MBL2 increase colon cancer susceptibility in African Americans. Cancer Res; 72(6); 1467–77. ©2012 AACR.
Data from RANK Induces Epithelial–Mesenchymal Transition and Stemness in Human Mammary Epithelial Cells and Promotes Tumorigenesis and Metastasis
Authors: Palafox Marta , Ferrer Irene , Pellegrini Pasquale , Vila Sergi , Hernandez-Ortega Sara , Urruticoechea Ander , Climent Fina , Soler Maria Teresa , Muñoz Purificación , Viñals Francesc , Tometsko Mark , Branstetter Dan , Dougall William C. , González-Suárez Eva
Published: March 2024

Abstract
Paracrine signaling through receptor activator of NF-κB (RANK) pathway mediates the expansion of mammary epithelia that occurs during pregnancy, and activation of RANK pathway promotes mammary tumorigenesis in mice. In this study we extend these previous data to human cells and show that the RANK pathway promotes the development of mammary stem cells and breast cancer. Overexpression of RANK (FL-RANK) in a panel of tumoral and normal human mammary cells induces the expression of breast cancer stem and basal/stem cell markers. High levels of RANK in untransformed MCF10A cells induce changes associated with both stemness and transformation, including mammary gland reconstitution, epithelial–mesenchymal transition (EMT), increased migration, and anchorage-independent growth. In addition, spheroids of RANK overexpressing MCF10A cells display disrupted acinar formation, impair growth arrest and polarization, and luminal filling. RANK overexpression in tumor cells with nonfunctional BRCA1 enhances invasiveness in acinar cultures and increases tumorigenesis and metastasis in immunodeficient mice. High levels of RANK were found in human primary breast adenocarcinomas that lack expression of the hormone receptors, estrogen and progesterone, and in tumors with high pathologic grade and proliferation index; high RANK/RANKL expression was significantly associated with metastatic tumors. Together, our findings show that RANK promotes tumor initiation, progression, and metastasis in human mammary epithelial cells by increasing the population of CD44+CD24− cells, inducing stemness and EMT. These results suggest that RANK expression in primary breast cancer associates with poor prognosis. Cancer Res; 72(11); 2879–88. ©2012 AACR.
Data from Extracellular Matrix Protein CCN1 Limits Oncolytic Efficacy in Glioma
Authors: Haseley Amy , Boone Sean , Wojton Jeffrey , Yu Lianbo , Yoo Ji Young , Yu Jianhua , Kurozumi Kazuhiko , Glorioso Joseph C. , Caligiuri Michael A. , Kaur Balveen
Published: March 2024

Abstract
Oncolytic viral therapy has been explored widely as an option for glioma treatment but its effectiveness has remained limited. Cysteine rich 61 (CCN1) is an extracellular matrix (ECM) protein elevated in cancer cells that modulates their adhesion and migration by binding cell surface receptors. In this study, we examined a hypothesized role for CCN1 in limiting the efficacy of oncolytic viral therapy for glioma, based on evidence of CCN1 induction that occurs in this setting. Strikingly, we found that exogenous CCN1 in glioma ECM orchestrated a cellular antiviral response that reduced viral replication and limited cytolytic efficacy. Gene expression profiling and real-time PCR analysis revealed a significant induction of type-I interferon responsive genes in response to CCN1 exposure. This induction was accompanied by activation of the Jak/Stat signaling pathway, consistent with induction of an innate antiviral cellular response. Both effects were mediated by the binding of CCN1 to the cell surface integrin α6β1, activating its signaling and leading to rapid secretion of interferon-α, which was essential for the innate antiviral effect. Together, our findings reveal how an integrin signaling pathway mediates activation of a type-I antiviral interferon response that can limit the efficacy of oncolytic viral therapy. Furthermore, they suggest therapeutic interventions to inhibit CCN1–integrin α6 interactions to sensitize gliomas to viral oncolysis. Cancer Res; 72(6); 1353–62. ©2012 AACR.
Data from Frequent PVT1 Rearrangement and Novel Chimeric Genes PVT1-NBEA and PVT1-WWOX Occur in Multiple Myeloma with 8q24 Abnormality
Authors: Nagoshi Hisao , Taki Tomohiko , Hanamura Ichiro , Nitta Masakazu , Otsuki Takemi , Nishida Kazuhiro , Okuda Keiko , Sakamoto Natsumi , Kobayashi Satoru , Yamamoto-Sugitani Mio , Tsutsumi Yasuhiko , Kobayashi Tsutomu , Matsumoto Yosuke , Horiike Shigeo , Kuroda Junya , Taniwaki Masafumi
Published: March 2024

Abstract
Chromosome 8q24 rearrangements are occasionally found in multiple myeloma and are associated with tumor progression. The 8q24 rearrangements were detected by FISH in 12 of 54 patients with multiple myeloma (22.2%) and in 8 of 11 multiple myeloma cell lines (72.7%). The breakpoints of 8q24 in 10 patients with multiple myeloma and in all multiple myeloma cell lines were assigned to a 360 kb segment, which was divided into 4 regions: approximately 120 kb centromeric to MYC (5′ side of MYC), the region centromerically adjacent to PVT1 (∼ 170 kb region, including MYC, of 5′ side of PVT1), the PVT1 region, and the telomeric region to PVT1. PVT1 rearrangements were most common and found in 7 of 12 patients (58.3%) and 5 of 8 cell lines (62.5%) with 8q24 abnormalities. A combination of spectral karyotyping (SKY), FISH, and oligonucleotide array identified several partner loci of PVT1 rearrangements, such as 4p16, 4q13, 13q13, 14q32, and 16q23-24. Two novel chimeric genes were identified: PVT1-NBEA in the AMU-MM1 cell line harboring t(8;13)(q24;q13) and PVT1-WWOX in RPMI8226 cell line harboring der(16)t(16;22)ins(16;8)(q23;q24). The PVT1-NBEA chimera in which PVT1 exon 1 was fused to NBEA exon 2 and the PVT1-WWOX in which PVT1 exon 1 was fused to WWOX exon 9 were associated with the expression of abnormal NBEA and WWOX lacking their N-terminus, respectively. These findings suggest that PVT1 rearrangements may represent a novel molecular paradigm underlying the pathology of 8q24 rearrangement–positive multiple myeloma. Cancer Res; 72(19); 4954–62. ©2012 AACR.
Data from Neuropilin-1 Stimulates Tumor Growth by Increasing Fibronectin Fibril Assembly in the Tumor Microenvironment
Authors: Yaqoob Usman , Cao Sheng , Shergill Uday , Jagavelu Kumaravelu , Geng Zhimin , Yin Meng , de Assuncao Thiago M. , Cao Ying , Szabolcs Anna , Thorgeirsson Snorri , Schwartz Martin , Yang Ju Dong , Ehman Richard , Roberts Lewis , Mukhopadhyay Debabrata , Shah Vijay H.
Published: March 2024

Abstract
The tumor microenvironment, including stromal myofibroblasts and associated matrix proteins, regulates cancer cell invasion and proliferation. Here, we report that neuropilin-1 (NRP-1) orchestrates communications between myofibroblasts and soluble fibronectin that promote α5β1 integrin–dependent fibronectin fibril assembly, matrix stiffness, and tumor growth. Tumor growth and fibronectin fibril assembly were reduced by genetic depletion or antibody neutralization of NRP-1 from stromal myofibroblasts in vivo. Mechanistically, the increase in fibronectin fibril assembly required glycosylation of serine 612 of the extracellular domain of NRP-1, an intact intracellular NRP-1 SEA domain, and intracellular associations between NRP-1, the scaffold protein GIPC, and the nonreceptor tyrosine kinase c-Abl that augmented α5β1 fibronectin fibril assembly activity. Analysis of human cancer specimens established an association between tumoral NRP-1 levels and clinical outcome. Our findings indicate that NRP-1 activates the tumor microenvironment, thereby promoting tumor growth. These results not only identify new molecular mechanisms of fibronectin fibril assembly but also have important implications for therapeutic targeting of the myofibroblast in the tumor microenvironment. Cancer Res; 72(16); 4047–59. ©2012 AACR.
Data from The ABL Switch Control Inhibitor DCC-2036 Is Active against the Chronic Myeloid Leukemia Mutant BCR-ABLT315I and Exhibits a Narrow Resistance Profile
Authors: Eide Christopher A. , Adrian Lauren T. , Tyner Jeffrey W. , Mac Partlin Mary , Anderson David J. , Wise Scott C. , Smith Bryan D. , Petillo Peter A. , Flynn Daniel L. , Deininger Michael W.N. , O'Hare Thomas , Druker Brian J.
Published: March 2024

Abstract
Acquired point mutations within the BCR-ABL kinase domain represent a common mechanism of resistance to ABL inhibitor therapy in patients with chronic myeloid leukemia (CML). The BCR-ABLT315I mutant is highly resistant to imatinib, nilotinib, and dasatinib, and is frequently detected in relapsed patients. This critical gap in resistance coverage drove development of DCC-2036, an ABL inhibitor that binds the switch control pocket involved in conformational regulation of the kinase domain. We evaluated the efficacy of DCC-2036 against BCR-ABLT315I and other mutants in cellular and biochemical assays and conducted cell-based mutagenesis screens. DCC-2036 inhibited autophosphorylation of ABL and ABLT315I enzymes, and this activity was consistent with selective efficacy against Ba/F3 cells expressing BCR-ABL (IC50: 19 nmol/L), BCR-ABLT315I (IC50: 63 nmol/L), and most kinase domain mutants. Ex vivo exposure of CML cells from patients harboring BCR-ABL or BCR-ABLT315I to DCC-2036 revealed marked inhibition of colony formation and reduced phosphorylation of the direct BCR-ABL target CrkL. Cell-based mutagenesis screens identified a resistance profile for DCC-2036 centered around select P-loop mutations (G250E, Q252H, Y253H, E255K/V), although a concentration of 750 nmol/L DCC-2036 suppressed the emergence of all resistant clones. A decreased concentration of DCC-2036 (160 nmol/L) in dual combination with either nilotinib or dasatinib achieved the same zero outgrowth result. Further screens for resistance due to BCR-ABL compound mutations (two mutations in the same clone) identified BCR-ABLE255V / T315I as the most resistant mutant. Taken together, these findings support continued evaluation of DCC-2036 as an important new agent for treatment-refractory CML. Cancer Res; 71(9); 3189–95. ©2011 AACR.
Data from Novel Transcriptional Targets of the SRY-HMG Box Transcription Factor SOX4 Link Its Expression to the Development of Small Cell Lung Cancer
Authors: Castillo Sandra D. , Matheu Ander , Mariani Niccolo , Carretero Julian , Lopez-Rios Fernando , Lovell-Badge Robin , Sanchez-Cespedes Montse
Published: March 2024

Abstract
The HMG box transcription factor SOX4 involved in neuronal development is amplified and overexpressed in a subset of lung cancers, suggesting that it may be a driver oncogene. In this study, we sought to develop this hypothesis including by defining targets of SOX4 that may mediate its involvement in lung cancer. Ablating SOX4 expression in SOX4-amplified lung cancer cells revealed a gene expression signature that included genes involved in neuronal development such as PCDHB, MYB, RBP1, and TEAD2. Direct recruitment of SOX4 to gene promoters was associated with their upregulation upon ectopic overexpression of SOX4. We confirmed upregulation of the SOX4 expression signature in a panel of primary lung tumors, validating their specific response by a comparison using embryonic fibroblasts from Sox4-deficient mice. Interestingly, we found that small cell lung cancer (SCLC), a subtype of lung cancer with neuroendocrine characteristics, was generally characterized by high levels of SOX2, SOX4, and SOX11 along with the SOX4-specific gene expression signature identified. Taken together, our findings identify a functional role for SOX genes in SCLC, particularly for SOX4 and several novel targets defined in this study. Cancer Res; 72(1); 176–86. ©2011 AACR.
Data from Induction of the Stem-like Cell Regulator CD44 by Rho Kinase Inhibition Contributes to the Maintenance of Colon Cancer–Initiating Cells
Authors: Ohata Hirokazu , Ishiguro Tatsuya , Aihara Yuki , Sato Ai , Sakai Hiroaki , Sekine Shigeki , Taniguchi Hirokazu , Akasu Takayuki , Fujita Shin , Nakagama Hitoshi , Okamoto Koji
Published: March 2024

Abstract
The difficulty in expanding cancer-initiating cells in vitro is one of major obstacles for their biochemical characterization. We found that Rho kinase (ROCK) inhibitors as well as blebbistatin, a myosin II inhibitor, greatly facilitated the establishment of spheroids from primary colon cancer. The spheroid cells expressed cancer stem cell markers, showed the ability to differentiate, and induced tumors in mice. The spheroids were composed of cells that express various levels of CD44, whereas CD44high cells were associated with increased sphere-forming ability, expression of the activating form of β-catenin, and elevated levels of glycolytic genes, CD44−/low cells showed increased levels of differentiation markers and apoptotic cells. The spheroid cells expressed variant forms of CD44 including v6, and the induction of the variants was associated with the activating phosphorylation of c-Met. As expected from the predicted hierarchy, CD44high cells differentiated into CD44−/low cells. Unexpectedly, a fraction of CD44−/low cells generated CD44high cells, and the ROCK inhibitor or blebbistatin primed the transition by inducing CD44 expression. We propose that the transition from CD44−/low to CD44high state helps to maintain a CD44high fraction and the tumorigenic diversity in colon cancer. Cancer Res; 72(19); 5101–10. ©2012 AACR.