bluuebunny/crossref_metadata_2025 huggingface dataset:
Tumor-Induced Senescent T Cells with Suppressor Function: A Potential Form of Tumor Immune Evasion
Authors: Montes Carolina L. , Chapoval Andrei I. , Nelson Jonas , Orhue Vbenosa , Zhang Xiaoyu , Schulze Dan H. , Strome Scott E. , Gastman Brian R.
Published: February 2008

Senescent and suppressor T cells are reported to be increased in select patients with cancer and are poor prognostic indicators. Based on the association of these T cells and poor outcomes, we hypothesized that tumors induce senescence in T cells, which negatively effects antitumor immunity. In this report, we show that human T cells from healthy donors incubated with tumor for only 6 h at a low tumor to T-cell ratio undergo a senescence-like phenotype, characterized by the loss of CD27 and CD28 expression and telomere shortening. Tumor-induced senescence of T cells is induced by soluble factors and triggers increases in expression of senescence-associated molecules such as p53, p21, and p16. Importantly, these T cells are not only phenotypically altered, but also functionally altered as they can suppress the proliferation of responder T cells. This suppression requires cell-to-cell contact and is mediated by senescent CD4+ and CD8+ subpopulations, which are distinct from classically described natural T regulatory cells. Our observations support the novel concept that tumor can induce senescent T cells with suppressor function and may effect both the diagnosis and treatment of cancer. [Cancer Res 2008;68(3):870–9]
Multiple Alternative Splicing Markers for Ovarian Cancer
Authors: Klinck Roscoe , Bramard Anne , Inkel Lyna , Dufresne-Martin Geneviève , Gervais-Bird Julien , Madden Richard , Paquet Éric R. , Koh ChuShin , Venables Julian P. , Prinos Panagiotis , Jilaveanu-Pelmus Manuela , Wellinger Raymund , Rancourt Claudine , Chabot Benoit , Abou Elela Sherif
Published: February 2008

Intense efforts are currently being directed toward profiling gene expression in the hope of developing better cancer markers and identifying potential drug targets. Here, we present a sensitive new approach for the identification of cancer signatures based on direct high-throughput reverse transcription-PCR validation of alternative splicing events. This layered and integrated system for splicing annotation (LISA) fills a gap between high-throughput microarray studies and high-sensitivity individual gene investigations, and was created to monitor the splicing of 600 cancer-associated genes in 25 normal and 21 serous ovarian cancer tissues. Out of >4,700 alternative splicing events screened, the LISA identified 48 events that were significantly associated with serous ovarian tumor tissues. In a further screen directed at 39 ovarian tissues containing cancer pathologies of various origins, our ovarian cancer splicing signature successfully distinguished all normal tissues from cancer. High-volume identification of cancer-associated splice forms by the LISA paves the way for the use of alternative splicing profiling to diagnose subtypes of cancer. [Cancer Res 2008;68(3):657–63]
Tumor Immunobiological Differences in Prostate Cancer between African-American and European-American Men
Authors: Wallace Tiffany A. , Prueitt Robyn L. , Yi Ming , Howe Tiffany M. , Gillespie John W. , Yfantis Harris G. , Stephens Robert M. , Caporaso Neil E. , Loffredo Christopher A. , Ambs Stefan
Published: February 2008

The incidence and mortality rates of prostate cancer are significantly higher in African-American men when compared with European-American men. We tested the hypothesis that differences in tumor biology contribute to this survival health disparity. Using microarray technology, we obtained gene expression profiles of primary prostate tumors resected from 33 African-American and 36 European-American patients. These tumors were matched on clinical variables. We also evaluated 18 nontumor prostate tissues from seven African-American and 11 European-American patients. The resulting datasets were analyzed for expression differences on the gene and pathway level comparing African-American with European-American patients. Our analysis revealed a significant number of genes, e.g., 162 transcripts at a false-discovery rate of ≤5% to be differently expressed between African-American and European-American patients. Using a disease association analysis, we identified a common relationship of these transcripts with autoimmunity and inflammation. These findings were corroborated on the pathway level with numerous differently expressed genes clustering in immune response, stress response, cytokine signaling, and chemotaxis pathways. Several known metastasis-promoting genes, including autocrine mobility factor receptor, chemokine (C-X-C motif) receptor 4, and matrix metalloproteinase 9, were more highly expressed in tumors from African-Americans than European-Americans. Furthermore, a two-gene tumor signature that accurately differentiated between African-American and European-American patients was identified. This finding was confirmed in a blinded analysis of a second sample set. In conclusion, the gene expression profiles of prostate tumors indicate prominent differences in tumor immunobiology between African-American and European-American men. The profiles portray the existence of a distinct tumor microenvironment in these two patient groups. [Cancer Res 2008;68(3):927–36]
Tumor Cell–Secreted Caveolin-1 Has Proangiogenic Activities in Prostate Cancer
Authors: Tahir Salahaldin A. , Yang Guang , Goltsov Alexei A. , Watanabe Masami , Tabata Ken-ichi , Addai Josephine , Fattah El Moataz Abdel , Kadmon Dov , Thompson Timothy C.
Published: February 2008

Caveolin, a major structural component of specialized plasma membrane invaginations (caveolae) that participate in diverse cellular activities, has been implicated in the pathogenesis of several human diseases, including cancer. We showed in earlier studies that caveolin-1 (cav-1) is consistently and strongly overexpressed in metastatic prostate cancer and is secreted in a biologically active form by virulent prostate cancer cells. Using both in vitro and in vivo model systems, we now present evidence supporting a proangiogenic role for cav-1 in prostate cancer development and progression. Recombinant cav-1 (rcav-1) was taken up by cav-1−/− endothelial cells through either a lipid raft/caveolae- or clathrin-dependent mechanism, leading to specific angiogenic activities (tubule formation, cell migration, and nitric oxide production) that were mediated by rcav-1 stimulation of the PI3K-Akt-eNOS signaling module. Pathologic angiogenesis induced by cav-1 in prostate cancer–bearing mice correlated with an increased frequency, number, and size of lung metastases. We propose that in addition to its antiapoptotic role, cav-1 secreted by prostate cancer cells functions critically as a proangiogenic factor in metastatic progression of this tumor. These new insights into cav-1 function in prostate cancer may provide a base for the design of clinically applicable therapeutic strategies. [Cancer Res 2008;68(3):731–9]
Tristetraprolin Down-regulates Interleukin-8 and Vascular Endothelial Growth Factor in Malignant Glioma Cells
Authors: Suswam Esther , Li Yanyan , Zhang Xiaowen , Gillespie G. Yancey , Li Xuelin , Shacka John J. , Lu Liang , Zheng Lei , King Peter H.
Published: February 2008

Malignant gliomas are highly aggressive tumors of the central nervous system that rely on production of growth factors for tumor progression. Vascular endothelial growth factor (VEGF), interleukin-8 (IL-8), and tumor necrosis factor-α, for example, are up-regulated in these tumors to promote angiogenesis and proliferation. RNA stability, mediated through adenine and uridine-rich elements (ARE) in the 3′ untranslated region, is a critical control point for regulating these growth factors. RNA half-life is predominantly governed by a balance between stabilizing and destabilizing factors that bind to ARE. We have previously shown that the stabilizing factor HuR is overexpressed in malignant gliomas and linked to RNA stabilization of angiogenic growth factors. Here, we report that the destabilizing factor tristetraprolin (TTP) is also ubiquitously expressed in primary malignant glioma tissues and cell lines. In contrast to benign astrogliotic tissues, however, the protein was hyperphosphorylated, with evidence implicating the p38/mitogen-activated protein kinase (MAPK) pathway. Conditional overexpression of TTP as a transgene in malignant glioma cells led to RNA destabilization of IL-8 and VEGF and down-regulation of protein production. Analysis of in vivo RNA binding indicated a shift of mRNA toward ectopic TTP and away from endogenous HuR. This biochemical phenotype was associated with a decrease in cell proliferation, loss of cell viability, and apoptosis. We postulate that hyperphosphorylation of TTP via p38/MAPK promotes progression of malignant gliomas by negatively regulating its RNA destabilizing function. [Cancer Res 2008;68(3):674–82]
The Tumor Suppressor LKB1 Regulates Lung Cancer Cell Polarity by Mediating cdc42 Recruitment and Activity
Authors: Zhang Shumin , Schafer-Hales Katherine , Khuri Fadlo R. , Zhou Wei , Vertino Paula M. , Marcus Adam I.
Published: February 2008

The tumor suppressor LKB1 is mutated in 30% of non–small cell lung cancer (NSCLC) tumors and cell lines and is proposed to be a key regulator of epithelial cell polarity; however, how LKB1 regulates cancer cell polarity is not known. The experiments described herein show for the first time that LKB1 is a dynamic, actin-associated protein that rapidly polarizes to the leading edge of motile cancer cells. LKB1 proves to be essential for NSCLC polarity, because LKB1 depletion results in classic cell polarity defects, such as aberrant Golgi positioning, reduced lamellipodia formation, and aberrant morphology. To probe how LKB1 regulates these events, we show that LKB1 colocalizes at the cellular leading edge with two key components of the polarity pathway — the small rho GTPase cdc42 and its downstream binding partner p21-activated kinase (PAK). Importantly, LKB1 functionality is required for cdc42 polarization to the leading edge, maintaining active cdc42 levels, and downstream PAK phosphorylation. To do this, LKB1 interacts only with active form of cdc42 and PAK, but not with inactive cdc42. Taken together, these results show that LKB1 is a critical mediator of the NSCLC polarity program in lung cancer cells through a novel LKB1-cdc42-PAK pathway. [Cancer Res 2008;68(3):740–8]
Spontaneous Squamous Cell Carcinoma Induced by the Somatic Inactivation of Retinoblastoma and Trp53 Tumor Suppressors
Authors: Martínez-Cruz Ana Belén , Santos Mirentxu , Lara M. Fernanda , Segrelles Carmen , Ruiz Sergio , Moral Marta , Lorz Corina , García-Escudero Ramón , Paramio Jesús M.
Published: February 2008

Squamous cell carcinomas (SCC) represent the most aggressive type of nonmelanoma skin cancer. Although little is known about the causal alterations of SCCs, in organ-transplanted patients the E7 and E6 oncogenes of human papillomavirus, targeting the p53- and pRb-dependent pathways, have been widely involved. Here, we report the functional consequences of the simultaneous elimination of Trp53 and retinoblastoma (Rb) genes in epidermis using Cre-loxP system. Loss of p53, but not pRb, produces spontaneous tumor development, indicating that p53 is the predominant tumor suppressor acting in mouse epidermis. Although the simultaneous inactivation of pRb and p53 does not aggravate the phenotype observed in Rb-deficient epidermis in terms of proliferation and/or differentiation, spontaneous SCC development is severely accelerated in doubly deficient mice. The tumors are aggressive and undifferentiated and display a hair follicle origin. Detailed analysis indicates that the acceleration is mediated by premature activation of the epidermal growth factor receptor/Akt pathway, resulting in increased proliferation in normal and dysplastic hair follicles and augmented tumor angiogenesis. The molecular characteristics of this model provide valuable tools to understand epidermal tumor formation and may ultimately contribute to the development of therapies for the treatment of aggressive squamous cancer. [Cancer Res 2008;68(3):683–92]
Repression of B-Cell Linker (BLNK) and B-Cell Adaptor for Phosphoinositide 3-Kinase (BCAP) Is Important for Lymphocyte Transformation by Rel Proteins
Authors: Gupta Nupur , Delrow Jeffrey , Drawid Amar , Sengupta Anirvan M. , Fan Gaofeng , Gélinas Céline
Published: February 2008

Persistent Rel/nuclear factor-κB (NF-κB) activity is a hallmark of many human cancers, and the Rel proteins are implicated in leukemia/lymphomagenesis but the mechanism is not fully understood. Microarray analysis to identify transformation-impacting genes regulated by NF-κB's oncogenic v-Rel and c-Rel proteins uncovered that Rel protein expression leads to transcriptional repression of key B-cell receptor (BCR) components and signaling molecules like B-cell linker (BLNK), the B-cell adaptor for phosphoinositide 3-kinase (BCAP) and immunoglobulin λ light chain (Igλ), and is accompanied by a block in BCR-mediated activation of extracellular signal-regulated kinase, Akt, and c-Jun-NH2-kinase in response to anti-IgM. The BLNK and BCAP proteins were also down-regulated in lymphoid cells expressing a transformation-competent chimeric RelA/v-Rel protein, suggesting a correlation with the capacity of Rel proteins to transform lymphocytes. DNA-binding studies identified functional NF-κB–binding sites, and chromatin immunoprecipitation (ChIP) data showed binding of Rel to the endogenous blnk and bcap promoters in vivo. Importantly, restoration of either BLNK or BCAP expression strongly inhibited transformation of primary chicken lymphocytes by the potent NF-κB oncoprotein v-Rel. These findings are interesting because blnk and other BCR components and signaling molecules are down-regulated in primary mediastinal large B-cell lymphomas and Hodgkin's lymphomas, which depend on c-Rel for survival, and are consistent with the tumor suppressor function of BLNK. Overall, our results indicate that down-regulation of BLNK and BCAP is an important contributing factor to the malignant transformation of lymphocytes by Rel and suggest that gene repression may be as important as transcriptional activation for Rel's transforming activity. [Cancer Res 2008;68(3):808–14]
TBX3 Is Overexpressed in Breast Cancer and Represses p14ARF by Interacting with Histone Deacetylases
Authors: Yarosh Will , Barrientos Tomasa , Esmailpour Taraneh , Lin Limin , Carpenter Philip M. , Osann Kathryn , Anton-Culver Hoda , Huang Taosheng
Published: February 2008

TBX3 is a transcription factor of the T-box gene family. Mutations in the TBX3 gene can cause hypoplastic or absent mammary glands. Previous studies have shown that TBX3 might be associated with breast cancer. Here, we show that TBX3 is overexpressed in malignant cells of primary breast cancer tissues by immunohistochemistry. TBX3 interacts with histone deacetylases (HDAC) 1, 2, 3, and 5. TBX3 interacts with HDAC1, 2, and 3 via two distinct binding sites. However, deletion of the repression domain (amino acids 566–624) of TBX3 completely abolishes its interaction with HDAC5. Endogenous TBX3 and HDACs interaction and colocalization are found in a breast cancer cell line by coimmunoprecipitation and immunofluorescence, respectively. The functional significance of the interaction between TBX3 and HDAC is also tested in a p14ARF-luciferase reporter system. Results indicate that TBX3 represses expression of p14ARF tumor suppressor and that a HDAC inhibitor is able to reverse the TBX3 repressive function in a dosage-dependant manner. This study suggests that TBX3 may function by recruiting HDACs to the T-box binding site in the promoter region. TBX3 repression to its targets is dependent on HDAC activity. TBX3 may serve as a biomarker for breast cancer and have significant applications in both breast cancer diagnosis and treatment. [Cancer Res 2008;68(3):693–9]
Sixteen–Kinase Gene Expression Identifies Luminal Breast Cancers with Poor Prognosis
Authors: Finetti Pascal , Cervera Nathalie , Charafe-Jauffret Emmanuelle , Chabannon Christian , Charpin Colette , Chaffanet Max , Jacquemier Jocelyne , Viens Patrice , Birnbaum Daniel , Bertucci François
Published: February 2008

Breast cancer is a heterogeneous disease made of various molecular subtypes with different prognosis. However, evolution remains difficult to predict within some subtypes, such as luminal A, and treatment is not as adapted as it should be. Refinement of prognostic classification and identification of new therapeutic targets are needed. Using oligonucleotide microarrays, we profiled 227 breast cancers. We focused our analysis on two major breast cancer subtypes with opposite prognosis, luminal A (n = 80) and basal (n = 58), and on genes encoding protein kinases. Whole-kinome expression separated luminal A and basal tumors. The expression (measured by a kinase score) of 16 genes encoding serine/threonine kinases involved in mitosis distinguished two subgroups of luminal A tumors: Aa, of good prognosis and Ab, of poor prognosis. This classification and its prognostic effect were validated in 276 luminal A cases from three independent series profiled across different microarray platforms. The classification outperformed the current prognostic factors in univariate and multivariate analyses in both training and validation sets. The luminal Ab subgroup, characterized by high mitotic activity compared with luminal Aa tumors, displayed clinical characteristics and a kinase score intermediate between the luminal Aa subgroup and the luminal B subtype, suggesting a continuum in luminal tumors. Some of the mitotic kinases of the signature represent therapeutic targets under investigation. The identification of luminal A cases of poor prognosis should help select appropriate treatment, whereas the identification of a relevant kinase set provides potential targets. [Cancer Res 2008;68(3):767–76]
Mitochondrial Cytochrome B Gene Mutation Promotes Tumor Growth in Bladder Cancer
Authors: Dasgupta Santanu , Hoque Mohammad Obaidul , Upadhyay Sunil , Sidransky David
Published: February 2008

Mitochondria-encoded Cytochrome B (CYTB) gene mutations were reported in different cancers, but the effect of these mutations on cellular metabolism and growth is unknown. In a murine xenograft and human model of bladder cancer, we show the functional effect of overexpression of a 21-bp deletion mutation (mt) of CYTB. Overexpression of mtCYTB generated increased reactive oxygen species (ROS) accompanied by increased oxygen consumption and lactate production. MtCYTB overexpression induced significant tumor growth in vitro and in vivo by triggering rapid cell cycle progression through up-regulation of the nuclear factor-κB2 signaling pathway. Tumor-generated ROS induced in vitro lysis of normal splenocytes. Thus, we present physiologic and functional evidence for the role of a bonafide mitochondrial gene mutation in cancer. [Cancer Res 2008;68(3):700–06]
Tolerability, Pharmacodynamics, and Pharmacokinetics Studies of Depsipeptide (Romidepsin) in Patients with Acute Myelogenous Leukemia or Advanced Myelodysplastic Syndromes
Authors: Klimek Virginia M. , Fircanis Sophia , Maslak Peter , Guernah Ilhem , Baum Michael , Wu Nian , Panageas Katherine , Wright John J. , Pandolfi Pier Paolo , Nimer Stephen D.
Published: February 2008

Purpose: Epigenetic modulation of gene expression plays an important role in cancer, including leukemia. Furthermore, histone deacetylase inhibitors may induce the reexpression or repression of genes critical for normal hematopoiesis. The purpose of this study was to evaluate the toxicity, pharmacokinetic profile, and selected pharmacodynamic properties of the histone deacetylase inhibitor depsipeptide in patients with myelodysplastic syndromes (MDS) or acute myelogenous leukemia (AML).

Experimental Design: Depsipeptide was administered to MDS or AML patients at a (solid tumor) phase I dose of 18 mg/m2 i.v. on days 1 and 5 every 3 weeks. Toxicities and clinical activity were monitored and pharmacokinetic and pharmacodynamic studies were done.

Results: Twelve patients (nine with AML, three with MDS) received one to five cycles of depsipeptide. The most common grade 3/4 toxicities were febrile neutropenia/infection (five patients), neutropenia/thrombocytopenia (nine patients), nausea (nine patients), and asymptomatic hypophosphatemia (three patients). No clinically significant cardiac toxicity was observed. The best response of 11 assessed patients was one complete remission in a patient with AML, stable disease in six patients, and progression of disease in four patients. Exploratory laboratory studies showed modest but rapid increases in apoptosis and changes in myeloid maturation marker expression. Histone H3 and H4 acetylation levels were evaluated in five patients; no consistent changes were observed.

Conclusion: Depsipeptide therapy can be administered with acceptable short-term toxicity. However, gastrointestinal symptoms and fatigue seem to be treatment-limiting after multiple cycles. Depsipeptide monotherapy has limited clinical activity in unselected AML/MDS patients.
WP1066, a Novel JAK2 Inhibitor, Suppresses Proliferation and Induces Apoptosis in Erythroid Human Cells Carrying the JAK2 V617F Mutation
Authors: Verstovsek Srdan , Manshouri Taghi , Quintás-Cardama Alfonso , Harris David , Cortes Jorge , Giles Francis J. , Kantarjian Hagop , Priebe Waldemar , Estrov Zeev
Published: February 2008

Purpose: The discovery of an activating somatic mutation in codon 617 of the gene encoding the Janus kinase (JAK)-2 (JAK2 V617F) in patients with myeloproliferative disorders has opened new avenues for the development of targeted therapies for these malignancies. However, no effective JAK2 inhibitors are currently available for clinical use.

Experimental Design: We investigated the activity of (E)-3(6-bromopyridin-2-yl)-2-cyano-N-(S0-1phenylethyl)acrylamide (WP1066), a novel analogue of the JAK2 inhibitor AG490, in JAK2 V617F–positive erythroleukemia HEL cells and in blood cells from patients with polycythemia vera.

Results: We found that WP1066 significantly inhibited JAK2 and its downstream signal transducer and activator of transcription-3, signal transducer and activator of transcription-5, and extracellular signal-regulated kinase-1/2 pathways in a dose- and time-dependent manner. As a result, WP1066 concentrations in the low micromolar range induced time- and dose-dependent antiproliferative and proapoptotic effects in HEL cells. As expected, WP1066 inhibited the proliferation of peripheral blood hematopoietic progenitors of patients with polycythemia vera carrying the JAK2 V617F mutation in a dose-dependent manner.

Conclusions: Our data suggest that WP1066 is active both in vitro and ex vivo and should be further developed for the treatment of neoplasms expressing the JAK2 V617F mutation.
Immune Function Abnormalities in Peripheral Blood Mononuclear Cell Cytokine Expression Differentiates Stages of Cutaneous T-Cell Lymphoma/Mycosis Fungoides
Authors: Chong Benjamin F. , Wilson Adam J. , Gibson Heather M. , Hafner Mikehl S. , Luo Yu , Hedgcock Carrie J. , Wong Henry K.
Published: February 2008

Purpose: Mycosis fungoides (MF) is a cutaneous T-cell lymphoma (CTCL) characterized by neoplastic skin-homing T cells. To better understand the immunopathogenesis of MF, we analyzed the functional ability of peripheral blood mononuclear cells (PBMC) from early and late MF/CTCL patients to express cytokine genes. In late stage MF/CTCL, patients were separated into those with blood involvement (+B) and without blood involvement (−B).

Experimental Design: We analyzed TH1 (interleukin 2 (IL-2), IFN-γ), TH2 (IL-4, IL-5, IL-10, IL-13), and TH17 (IL-17) cytokine gene expression from activated PBMCs from normal (n = 12), psoriasis (n = 6), early MF/CTCL (n = 11), and late MF/CTCL+B (n = 4) and MF/CTCL−B (n = 3) by quantitative real-time PCR.

Results: PBMCs from early MF/CTCL and psoriasis showed higher induction of IL-2, IL-4, and IFN-γ genes than those from normal and late MF/CTCL−B and MF/CTCL+B (P < 0.05) in descending order. PBMCs from late MF/CTCL−B exhibited generally the highest level of IL-5, IL-10, IL-13, and IL-17 expression compared with the other groups. PBMCs from early MF/CTCL and late MF/CTCL−B had similarly elevated IL-13 and IL-17. Of all groups, PBMCs from late MF/CTCL+B had the lowest levels of IL-2 (P < 0.05), IL-4, IFN-γ, IL-13, and IL-17.

Conclusions: The different pattern of cytokine gene expression suggests a change in immune function in MF/CTCL from early MF/CTCL to late MF/CTCL−B to late MF/CTCL+B. These stages are consistent with localized disease associated with an anti-tumor immune response and late MF/CTCL associated with a loss of immune function mediated by malignant T cells that share regulatory T cell–like properties.
Prognostic Value of CCN3 in Osteosarcoma
Authors: Perbal Bernard , Zuntini Monia , Zambelli Diana , Serra Massimo , Sciandra Marika , Cantiani Lara , Lucarelli Enrico , Picci Piero , Scotlandi Katia
Published: February 2008

Purpose: Osteosarcoma, the most common bone tumor, lacks prognostic markers that could distinguish patients before therapy and drive treatment choices. We assessed the prognostic value of CCN1, CCN2, and CCN3 genes, involved in fundamental biological processes.

Experimental Design: Expression of CCN1, CCN2, and CCN3 was measured by quantitative PCR in 45 newly diagnosed osteosarcomas. Cancer-specific survival was estimated using the Kaplan-Meier method. Associations with osteoblastic differentiation and/or drug response genes were assessed in tumor cells using Spearman correlation and Fisher's exact tests.

Results: CCN1 and CCN2 expression was associated with genes involved in commitment of mesenchymal stem cells toward osteoblasts and in early phases of osteoblastic differentiation (RUNX family genes; cadherin 4, 11, and 13; jun and fos; collagen I and SPARC). Although CCN3 is barely expressed in normal proliferating osteoblasts and mesenchymal stem cells, its expression was generally high in osteosarcoma and its level of expression did not correlate with any specific osteoblastic differentiation genes. High expression of CCN3 significantly correlated with worse prognosis in osteosarcoma. This may be only partly explained by the association with the expression of multidrug resistance–related protein 1 and 4, two ATP-binding cassette transporters that also acted as predictors of worse outcome in our study.

Conclusions: Our study showed temporal and coordinated expression of CCN1, CCN2, and CCN3 genes during osteoblastic differentiation and highlighted significant differences between human normal and osteosarcoma cell differentiation in vitro. CCN1 and CCN2 expression shows no prognostic relevance in osteosarcoma. In contrast, assessment for CCN3 expression levels at diagnosis may represent a useful molecular tool to early identification of patients with different prognosis.
Immune Expression and Inhibition of Heat Shock Protein 90 in Uveal Melanoma
Authors: Faingold Dana , Marshall Jean-Claude , Antecka Emilia , Di Cesare Sebastian , Odashiro Alexandre N. , Bakalian Silvin , Fernandes Bruno F. , Burnier Miguel N.
Published: February 2008

Purpose: To examine the immunohistochemical profile of heat shock protein 90 (Hsp90) in uveal melanoma and the cytotoxicity of an Hsp90 inhibitor, 17-allylamino-17-demethoxygeldanamycin (17-AAG), in uveal melanoma cell lines.

Experimental Design: Hsp90 expression was determined by immunohistochemistry in 44 paraffin-embedded sections of primary human uveal melanoma and in five uveal melanoma cell lines (92.1, OCM-1, MKT-BR, SP6.5, and UW-1). Sulforhodamine B–based proliferation assay was used to compare uveal melanoma cell growth with a range of concentrations of 17-AAG. Changes in cell migration, invasion, cell cycle fractions, and apoptotic activity were also evaluated. Expression of intracellular proteins was determined by Western blot analysis after 17-AAG exposure.

Results: Immunohistochemical expression of Hsp90 was identified in 68% of the paraffin-embedded sections and significantly associated with largest tumor dimension (P = 0.03). 17-AAG significantly reduced the proliferation rates of uveal melanoma cell lines, with concentrations of 100 to 0.1 μmol/L. 17-AAG also significantly reduced the migratory and invasive capabilities of uveal melanoma cell lines. Cell cycle analysis showed that 17-AAG induced accumulations of cells in G1. Caspase-3 protease activity analysis, a marker for apoptosis, showed a significant increase after drug exposure. The cytotoxic effect of 17-AAG was associated with decreased levels of phosphorylated Akt and cyclin-dependent kinase 4.

Conclusions: The immunohistochemical expression of Hsp90 in uveal melanoma indicates worse prognosis. To the best of our knowledge, this is the first report showing the inhibitory effect on uveal melanoma cells using 17-AAG to target Hsp90. Therefore, Hsp90 may be used as a potential target for treatment of patients with uveal melanoma.
Polycyclic Aromatic Hydrocarbon–DNA Adducts in Prostate and Biochemical Recurrence after Prostatectomy
Authors: Rybicki Benjamin A. , Neslund-Dudas Christine , Bock Cathryn H. , Rundle Andrew , Savera Adnan T. , Yang James J. , Nock Nora L. , Tang Deliang
Published: February 2008

Purpose: DNA adduct levels may be influenced by metabolic activity, DNA repair capabilities, and genomic integrity, all of which play a role in cancer progression.

Experimental Design: To determine if elevated DNA adducts are a marker for prostate cancer progression, we measured polycyclic aromatic hydrocarbon–DNA adducts by immunohistochemistry in prostate cells of 368 surgical prostate cancer patients treated at the Henry Ford Hospital in Detroit, Michigan, between September 1999 and July 2004. Patients were followed up to 5 years after surgery with relative risk for biochemical recurrence (BCR) estimated with a Cox proportional hazards model that adjusted for standard clinical risk factors.

Results: At 1 year of follow-up, patients with adduct levels above the median in tumor cells [hazard ratio (HR), 2.40; 95% confidence interval (95% CI), 1.10-5.27] and nontumor cells (HR, 3.22; 95% CI, 1.40-7.39) had significant increased risk of BCR, but these HRs decreased to 1.12 (95% CI, 0.68-1.83) and 1.46 (95% CI, 0.89-2.41) in tumor and nontumor cells at 5 years postsurgery. When we restricted our analysis to patients with advanced-stage (III+) disease, those with high adduct levels in either tumor (53.5% versus 30.2%; P = 0.07) or nontumor (55.2% versus 28.6%; P = 0.02) cells had BCR rates almost 2-fold higher. In race-stratified analyses, the greatest risk of BCR associated with high adduct levels (in nontumor cells) was for African American patients younger than 60 years old (HR, 3.79; 95% CI, 1.01-14.30).

Conclusions: High polycyclic aromatic hydrocarbon–DNA adduct levels in nontumor prostate cells are most strongly associated with BCR between 1 and 2 years after surgery and in patient subsets defined by younger age, advanced tumor stage, and African American race.
Effective Inhibition of the Epidermal Growth Factor/Epidermal Growth Factor Receptor Binding by Anti–Epidermal Growth Factor Antibodies Is Related to Better Survival in Advanced Non–Small-Cell Lung Cancer Patients Treated with the Epidermal Growth Factor Cancer Vaccine
Authors: García Beatriz , Neninger Elia , de la Torre Ana , Leonard Idrissa , Martínez Rocío , Viada Carmen , González Gisela , Mazorra Zaima , Lage Agustín , Crombet Tania
Published: February 2008

Purpose: Epidermal growth factor (EGF) might be a suitable immunotherapeutic target in non–small-cell lung cancer (NSCLC). Our approach consists of active immunotherapy with EGF. The aim of the study is to characterize the humoral response and its effects on signal transduction in relation with the clinical outcome.

Experimental Design: Eighty NSCLC patients treated with first-line chemotherapy were randomized to receive the EGF vaccine or supportive care. EGF concentration in sera, anti-EGF antibodies and their capacity to inhibit the binding between EGF/EGF receptor (EGFR), and the EGFR phosphorylation were measured.

Results: Seventy-three percent of vaccinated patients developed a good antibody response, whereas none of the controls did. In good antibody-responder patients, self EGF in sera was significantly reduced. In 58% of vaccinated patients, the post-immune sera inhibited EGF/EGFR binding; in the control group, no inhibition occurred. Post-immune sera inhibited the EGFR phosphorylation whereas sera from control patients did not have this capacity. Good antibody-responder patients younger than 60 years had a significantly better survival. A high correlation between anti-EGF antibody titers, EGFR phosphorylation inhibition, and EGF/EGFR binding inhibition was found. There was a significantly better survival for vaccinated patients that showed the higher capacity to inhibit EGF/EGFR binding and for those who showed an immunodominance by the central region of EGF molecule.

Conclusions: Immunization with the EGF vaccine induced neutralizing anti-EGF antibodies capable of inhibiting EGFR phosphorylation. There was a significant positive correlation between antibody titers, EGF/EGFR binding inhibition, immunodominance of anti-EGF antibodies, and survival in advanced NSCLC patients.
Aberrant Expression of Connexin 26 Is Associated with Lung Metastasis of Colorectal Cancer
Authors: Ezumi Koji , Yamamoto Hirofumi , Murata Kohei , Higashiyama Masahiko , Damdinsuren Bazarragchaa , Nakamura Yurika , Kyo Naganori , Okami Jiro , Ngan Chew Yee , Takemasa Ichiro , Ikeda Masataka , Sekimoto Mitsugu , Matsuura Nariaki , Nojima Hiroshi , Monden Morito
Published: February 2008

Purpose: Connexin 26 (Cx26) is one of the gap junction–forming family members classically considered to be tumor suppressors. However, recent studies show association of elevated expression of Cx26 with poor prognosis in several human malignancies. Furthermore, Cx26 has been observed to be indispensable to spontaneous metastasis of melanoma cells. Here, we assessed Cx26 expression in primary colorectal cancer (CRC) and the metastatic lesions to elucidate its role in metastasis.

Experimental Design: Cx26 expression was assessed in 25 adenomas, 167 CRCs, and normal mucosa, together with the metastatic lesions.

Results: Normal mucosa and adenomatous tissue expressed Cx26 mainly in the plasma membrane, whereas cancer cells mostly contained Cx26 in the cytoplasm. The incidence of aberrant Cx26 expression varied widely in CRC (mean, 49.5 ± 35.5%), and the expression levels were confirmed by Western blot and quantitative reverse transcription–PCR. Clinicopathologic survey revealed association of high expression with less differentiated histology and venous invasion (P = 0.0053 and P = 0.0084, respectively). Notably, high Cx26 expression was associated with shorter disease-free survival and shorter lung metastasis–free survival in 154 curatively resected CRC sets (P = 0.041 and P = 0.028, respectively). Survey of metastatic lesions revealed that lung metastasis, but not liver and lymph nodes metastases, expressed higher Cx26 than the CRC series or corresponding primary CRCs (P < 0.0001 and P = 0.0001, respectively).

Conclusions: These findings suggest that aberrant expression of Cx26 plays an essential role in lung metastasis. Thus, Cx26 is a promising therapeutic target, particularly for CRC patients who develop lung metastasis.
Follistatin Suppresses the Production of Experimental Multiple-Organ Metastasis by Small Cell Lung Cancer Cells in Natural Killer Cell–Depleted SCID Mice
Authors: Ogino Hirokazu , Yano Seiji , Kakiuchi Soji , Muguruma Hiroaki , Ikuta Kenji , Hanibuchi Masaki , Uehara Hisanori , Tsuchida Kunihiro , Sugino Hiromu , Sone Saburo
Published: February 2008

Purpose: Follistatin (FST), an inhibitor of activin, regulates a variety of biological functions, including cell proliferation, differentiation, and apoptosis. However, the role of FST in cancer metastasis is still unknown. Previous research established a multiple-organ metastasis model of human small cell lung cancer in natural killer cell–depleted SCID mice. In this model, i.v. inoculated tumor cells produced metastatic colonies in multiple organs including the lung, liver, and bone. The purpose of this study is to determine the role of FST in multiple-organ metastasis using this model.

Experimental Design: A human FST gene was transfected into the small cell lung cancer cell lines SBC-3 and SBC-5 and established transfectants secreting biologically active FST. The metastatic potential of the transfectants was evaluated using the metastasis model.

Results: FST-gene transfection did not affect the cell proliferation, motility, invasion, or adhesion to endothelial cells in vitro. I.v. inoculated SBC-3 or SBC-5 cells produced metastatic colonies into multiple organs, including the lung, liver, and bone in the natural killer cell–depleted SCID mice. FST transfectants produced significantly fewer metastatic colonies in these organs when compared with their parental cells or vector control clones. Immunohistochemical analyses of the liver metastases revealed that the number of proliferating tumor cells and the tumor-associated microvessel density were significantly less in the lesions produced by FST transfectants.

Conclusions: These results suggest that FST plays a critical role in the production of multiple-organ metastasis, predominantly by inhibiting the angiogenesis. This is the first report to show the role of FST in metastases.
Effective Treatment of Established Human Breast Tumor Xenografts in Immunodeficient Mice with a Single Dose of the α-Emitting Radioisotope Astatine-211 Conjugated to Anti-HER2/neu Diabodies
Authors: Robinson Matthew K. , Shaller Calvin , Garmestani Kayhan , Plascjak Paul S. , Hodge Kathryn M. , Yuan Qing-An , Marks James D. , Waldmann Thomas A. , Brechbiel Martin W. , Adams Gregory P.
Published: February 2008

Purpose: Successful radioimmunotherapy strategies depend on selecting radioisotopes with physical properties complementary to the biological properties of the targeting vehicle. Small, engineered antitumor antibody fragments are capable of rapid, highly specific tumor targeting in immunodeficient mouse models. We hypothesized that the C6.5 diabody, a noncovalent anti-HER2 single-chain Fv dimer, would be an ideal radioisotope carrier for the radioimmunotherapy of established tumors using the short-lived α-emitting radioisotope 211At.

Experimental Design: Immunodeficient nude mice bearing established HER2/neu–positive MDA-MB-361/DYT2 tumors treated with N-succinimidyl N-(4-[211At]astatophenethyl)succinamate (211At-SAPS)-C6.5 diabody. Additional cohorts of mice were treated with 211At-SAPS T84.66 diabody targeting the carcinoembryonic antigen or 211At-SAPS on a diabody specific for the Müllerian inhibiting substance type II receptor, which is minimally expressed on this tumor cell line.

Results: A single i.v. injection of 211At-SAPS C6.5 diabody led to a 30-day delay in tumor growth when a 20 μCi dose was administered and a 57-day delay in tumor growth (60% tumor-free after 1 year) when a 45 μCi dose was used. Treatment of mice bearing the same tumors with 211At-SAPS T84.66 diabody at the same doses led to a delay in tumor growth, but no complete responses, likely due to substantially lower expression of this antigen on the MDA-MB-361/DYT2 tumors. In contrast, a dose of 20 μCi of 211At-SAPS on the anti–Müllerian-inhibiting substance type II receptor diabody did not affect tumor growth rate, demonstrating specificity of the therapeutic effect.

Conclusions: These findings indicate that diabody molecules can be effective agents for targeted radioimmunotherapy of solid tumors using powerful, short-lived α-emitting radioisotopes.
Targeting Akt and Heat Shock Protein 90 Produces Synergistic Multiple Myeloma Cell Cytotoxicity in the Bone Marrow Microenvironment
Authors: Huston Alissa , Leleu Xavier , Jia Xiaoying , Moreau Anne-Sophie , Ngo Hai T. , Runnels Judith , Anderson Judy , Alsayed Yazan , Roccaro Aldo , Vallet Sonia , Hatjiharissi Evdoxia , Tai Yu-Tsu , Sportelli Peter , Munshi Nikhil , Richardson Paul , Hideshima Teru , Roodman David G. , Anderson Kenneth C. , Ghobrial Irene M.
Published: February 2008

Purpose: We hypothesized that targeting both Akt and heat shock protein (HSP) 90 would induce cytotoxic activity against multiple myeloma (MM) cells and target the bone marrow (BM) microenvironment to inhibit angiogenesis, osteoclast formation, as well as migration and adhesion of MM cells.

Experimental Design: MM cell lines were incubated with perifosine (5 and 10 μmol/L) and 17-(dimethylaminoethylamino)-17-demethoxygeldanamycin (17-DMAG; 50 and 100 nmol/L) alone and in combination.

Results: The combination of Akt inhibitor perifosine and HSP90 inhibitor 17-DMAG was synergistic in inducing MM cell cytotoxicity, evidenced by inhibition of DNA synthesis and induction of apoptosis. In addition, perifosine and 17-DMAG almost completely inhibited osteoclast formation: perifosine interfered with both early and late stages of osteoclast progenitor development, whereas 17-DMAG targeted only early stages. We next showed that combined therapy overcomes tumor growth and resistance induced by BM stromal cells and endothelial cells as well as the proliferative effect of exogenous interleukin-6, insulin-like growth factor-I, and vascular endothelial growth factor. Moreover, the combination also induced apoptosis and growth inhibition in endothelial cells and inhibited angiogenesis. Finally, we showed that the two agents prevented migration of MM cells toward stromal-derived factor-1 and vascular endothelial growth factor, which are present in the BM milieu, and also prevented adhesion of MM cells to fibronectin.

Conclusions: This study provides the preclinical framework for treatment protocols targeting both the Akt and HSP pathways in MM.
A Phase I Study of OGX-011, a 2′-Methoxyethyl Phosphorothioate Antisense to Clusterin, in Combination with Docetaxel in Patients with Advanced Cancer
Authors: Chi Kim N. , Siu Lillian L. , Hirte Hal , Hotte Sebastien J. , Knox Jennifer , Kollmansberger Christian , Gleave Martin , Guns Emma , Powers Jean , Walsh Wendy , Tu Dongsheng , Eisenhauer Elizabeth
Published: February 2008

Purpose: Clusterin is a cytoprotective chaperone protein that promotes cell survival and confers broad-spectrum treatment resistance. OGX-011 is a 2′-methoxyethyl–modified phosphorothioate antisense oligonucleotide that is complementary to clusterin mRNA, has a prolonged tissue half life, enhances drug efficacy in xenograft models, and reduces clusterin expression in humans with a biologically effective dose of 640 mg. The objective of this study was to determine a recommended phase II dose of OGX-011 in combination with docetaxel.

Experimental Design: Patients with cancers known from the literature to express clusterin were eligible. OGX-011 was given by 2-h i.v. infusion starting at 40 mg weekly after loading doses on days 1, 3, and 5. Docetaxel was given i.v. 30 mg/m2 weekly for 5 of 6 weeks (schedule A) or 75 mg/m2 every 3 weeks (schedule B). All patients had serial samples of peripheral blood mononuclear cells and serum assessed for clusterin expression.

Results: Forty patients were enrolled to eight cohorts. OGX-011 could be given at the full biologically effective single-agent dose of 640 mg with both docetaxel schedules. Toxic effects were primarily myelosuppression, fatigue, hair loss, gastrointestinal effects (expected docetaxel effects), as well as dose-related chills and fever (expected OGX-011 effects). OGX-011 AUC and Cmax increased proportionally with no apparent effect on docetaxel pharmacokinetics. At the end of cycle 1, serum clusterin showed mean decreases of 34% and 38% (range, 15-99%) at the 640-mg dose levels.

Conclusions: OGX-011 can be given at a biologically effective dose with standard doses of docetaxel. Phase II trials of combined OGX-011 and chemotherapy are ongoing in patients with prostate, breast, and lung cancers.
Higher Expression of the Androgen-Regulated Gene PSA/HK3 mRNA in Prostate Cancer Tissues Predicts Biochemical Recurrence-Free Survival
Authors: Sterbis Joseph R. , Gao Chunling , Furusato Bungo , Chen Yongmei , Shaheduzzaman Syed , Ravindranath Lakshmi , Osborn David J. , Rosner Inger L. , Dobi Albert , McLeod David G. , Sesterhenn Isabell A. , Srivastava Shiv , Cullen Jennifer , Petrovics Gyorgy
Published: February 2008

Purpose: Alterations of the androgen receptor (AR)-mediated signaling through numerous mechanisms are increasingly recognized in prostate cancer (CaP) progression. We hypothesized that the assessment of well-defined AR transcriptional targets (e.g., PSA/HK3 mRNA) in CaP tissues will provide in vivo readout of AR dysfunctions. Moreover, quantitative expression features of PSA/HK3 mRNA in prostate tumor cells may serve as a prognostic indicator of disease progression.

Experimental Design: Paired benign and malignant epithelial cells (242 specimens) were obtained from laser capture microdissection of frozen OCT-embedded tissue sections prepared from radical prostatectomy specimens of 121 patients. Quantitative expression of PSA/HK3 mRNA in the matched malignant and benign cells was analyzed by real-time reverse transcription-PCR.

Results: CaP cells express significantly lower PSA/HK3 mRNA levels than matched benign cells (P = 0.0133). Moreover, low PSA/HK3 mRNA expression in malignant cells was associated with increased risk of biochemical recurrence (P = 0.0217), as well as with time to recurrence (P = 0.0371), in patients with intermediate preoperative serum prostate-specific antigen levels (2-10 ng/mL). The expression of androgen-dependent genes in clinical samples correlates with each other in patients with higher expression of PSA/HK3 mRNA but not in patients with lower expression of PSA/HK3 mRNA reflecting AR pathway dysfunction.

Conclusions: Our study has unraveled a novel prognostic utility of quantitative measurements of PSA/HK3 mRNA reflecting AR transcriptional activity in CaP cells, which is independent of serum prostate-specific antigen. It also has potential in stratifying subsets of patients exhibiting progressive disease associated with dampened AR transcriptional functions who may be targeted by tailored therapeutic strategies.