bluuebunny/crossref_metadata_2025 huggingface dataset:
Functional Haplotypes in the Promoter of Matrix Metalloproteinase-2 Predict Risk of the Occurrence and Metastasis of Esophageal Cancer
Authors: Yu Chunyuan , Zhou Yifeng , Miao Xiaoping , Xiong Ping , Tan Wen , Lin Dongxin
Published: September 2005

Matrix metalloproteinase-2 (MMP-2) plays important roles in cancer development and aggression. Our previous studies revealed a strong association between the MMP-2 −1306C/T polymorphism and risk of several cancers. A novel −735C/T polymorphism in MMP-2 promoter has been identified but the function is undefined. This study examined our hypothesis that these two polymorphisms might have functional relevance and impact on risk of esophageal squamous cell carcinoma in the context of haplotype. Genotypes and haplotypes were analyzed in 527 cases and 777 controls and odds ratios (ORs) and 95% confidence intervals (CIs) were estimated by logistic regression. The function of the polymorphisms was examined by electrophoretic mobility shift assays, luciferase gene expression assays, and reverse transcriptase-PCR analyses. It was found that the −735C→T transition disrupts an Sp1 site and displays a lower promoter activity. The C-1306–C-735 haplotype had 7-fold increased luciferase expression and 3.7-fold increased MMP-2 mRNA levels in esophageal tissues compared with the T-1306–T-735 haplotype. A case-control analysis revealed a 1.52-fold (95% CI = 1.17–1.96) or 1.30-fold (95% CI = 1.04–1.63) excess risk of developing esophageal squamous cell carcinoma for the −1306CC or −735CC genotype carriers compared with noncarriers, respectively. A greater association was observed between elevated risk of developing esophageal squamous cell carcinoma and C-1306 or C-735 allele containing haplotypes, with the risk being highest for the C-1306–C-735 haplotype compared with the T-1306–T-735 haplotype (OR = 6.53; 95% CI = 2.78–15.33). The C-1306–C-735 haplotype was also associated with increased risk for distant metastasis of esophageal squamous cell carcinoma (OR = 3.34; 95% CI = 1.16–9.63). These findings suggest that the C-1306–C-735 haplotype in the MMP-2 promoter contributes to risk of the occurrence and metastasis of esophageal squamous cell carcinoma by increasing expression of MMP-2.
Sublethal Irradiation of Human Tumor Cells Modulates Phenotype Resulting in Enhanced Killing by Cytotoxic T Lymphocytes
Authors: Garnett Charlie T. , Palena Claudia , Chakarborty Mala , Tsang Kwong-Yok , Schlom Jeffrey , Hodge James W.
Published: September 2005

Local radiation of tumor masses is an established modality for the therapy of a range of human tumors. It has recently been recognized that doses of radiation, lower than or equal to those that cause direct cytolysis, may alter the phenotype of target tissue by up-regulating gene products that may make tumor cells more susceptible to T-cell–mediated immune attack. Previously, we demonstrated that radiation increased Fas (CD95) gene expression in carcinoembryonic antigen (CEA)-expressing murine tumor cells, which consequently enhanced their susceptibility to CEA-specific CTL-mediated killing. The present study was designed to determine whether these phenomena also occur with human tumor cells. Here, 23 human carcinoma cell lines (12 colon, 7 lung, and 4 prostate) were examined for their response to nonlytic doses of radiation (10 or 20 Gy). Seventy-two hours postirradiation, changes in surface expression of Fas (CD95), as well as expression of other surface molecules involved in T-cell–mediated immune attack such as intercellular adhesion molecule 1, mucin-1, CEA, and MHC class I, were examined. Twenty-one of the 23 (91%) cell lines up-regulated one or more of these surface molecules postirradiation. Furthermore, five of five irradiated CEA+/A2+ colon tumor cells lines demonstrated significantly enhanced killing by CEA-specific HLA-A2–restricted CD8+ CTLs compared with nonirradiated counterparts. We then used microarray analysis to broaden the scope of observed changes in gene expression after radiation and found that many additional genes had been modulated. These up-regulated gene products may additionally enhance the tumor cells’ susceptibility to T-cell–mediated immune attack or serve as additional targets for immunotherapy. Overall, the results of this study suggest that nonlethal doses of radiation can be used to make human tumors more amenable to immune system recognition and attack and form the rational basis for the combinatorial use of cancer vaccines and local tumor irradiation.
Cdc7 Inhibition Reveals a p53-Dependent Replication Checkpoint That Is Defective in Cancer Cells
Authors: Montagnoli Alessia , Tenca Pierluigi , Sola Francesco , Carpani Daniela , Brotherton Deborah , Albanese Clara , Santocanale Corrado
Published: September 2005

Cdc7 is an evolutionarily conserved kinase that regulates S phase by promoting replication origin activation. Down-regulation of Cdc7 by small interfering RNA in a variety of tumor cell lines causes an abortive S phase, leading to cell death by either p53-independent apoptosis or aberrant mitosis. Unlike replication fork blockade, Cdc7-depleted tumor cells do not elicit a robust checkpoint response; thus, inhibitory signals preventing additional cell cycle progression are not generated. In normal fibroblasts, however, a p53-dependent pathway actively prevents progression through a lethal S phase in the absence of sufficient Cdc7 kinase. We show that in this experimental system, p53 is required for the lasting maintenance of this checkpoint and for cell viability. With this work we reveal and begin to characterize a novel mechanism that regulates DNA synthesis in human cells, and we suggest that inhibition of Cdc7 kinase represents a promising approach for the development of a new generation of anticancer agents.
Ceramide Promotes Apoptosis in Lung Cancer-Derived A549 Cells by a Mechanism Involving c-Jun NH2-Terminal Kinase
Authors: Kurinna Svitlana M. , Tsao Chun Chui , Nica Alina Felicia , Jiffar Tilahun , Ruvolo Peter P.
Published: September 2005

Ceramide regulates diverse signaling pathways involving cell senescence, the cell cycle, and apoptosis. Ceramide is known to potently activate a number of stress-regulated enzymes, including the c-Jun NH2-terminal kinase (JNK). Although ceramide promotes apoptosis in human lung cancer-derived A549 cells, a role for JNK in this process is unknown. Here, we report that ceramide promotes apoptosis in A549 cells by a mechanism involving JNK. The JNK inhibitor SP600125 proved effective at protecting cells from the lethal effects of ceramide. To understand which JNK-mediated pathway may be involved, a number of JNK target proteins were examined, including the transcription factor, c-Jun, and the apoptotic regulatory proteins Bcl-XL and Bim. A549 cells exhibited basal levels of phosphorylated c-Jun in nuclear fractions, revealing that active c-Jun is present in these cells. Ceramide was found to inhibit c-Jun phosphorylation, suggesting that JNK-mediated phosphorylation of c-Jun is not likely involved in ceramide-induced apoptosis. Ceramide did not promote Bcl-XL phosphorylation. On the other hand, ceramide promoted phosphorylation of Bim and induced translocation of active JNK from the nucleus to the cytoplasm and mitochondrial fraction. Ceramide-mediated changes in localization of JNK were consistent with the observed changes in phosphorylation status of c-Jun and Bim. Furthermore, ceramide promoted Bim translocation to the mitochondria. Mitochondrial localization of Bim has been shown recently to promote apoptosis. These results suggest that JNK may participate in ceramide-induced apoptosis in A549 cells by a mechanism involving Bim.
Differentiation of Human Prostate Cancer PC-3 Cells Induced by Inhibitors of Inosine 5′-Monophosphate Dehydrogenase
Authors: Floryk Daniel , Tollaksen Sandra L. , Giometti Carol S. , Huberman Eliezer
Published: September 2005

To establish a system to study differentiation therapy drugs, we used the androgen-independent human prostate PC-3 tumor cell line as a target and mycophenolic acid (MPA), tiazofurin, or ribavirin, which are inhibitors of IMP dehydrogenase, as inducers. These inhibitors evoked replication arrest, caused an increase in cell size, and triggered vacuolization of the cytoplasm. By Northern and Western blotting and immunostaining, we demonstrated MPA-induced expression of 12 proteins reported to reside in prostasomes, organelles released by secretory luminal prostate cells. Additional MPA-induced proteins were identified by two-dimensional gel electrophoresis. Among these was keratin 17, a prostate cell differentiation marker. By Northern blotting, we also demonstrated the constitutive expression of keratins 8 and 18 and induced expression of keratin 19, three other prostate cell differentiation markers. In addition, we established that cells were committed to differentiate after the 2nd day of MPA treatment using guanosine, which can abrogate the effects of MPA. Based on the expression patterns of prostasomal proteins and keratins and the presence of tentative secretory vacuoles, we hypothesize that IMP dehydrogenase inhibitors induce androgen-independent PC-3 cells to mature into cells with a phenotype that resembles normal prostate luminal cells, but at their intermediate state of differentiation.
Tumor-Associated Endothelial Cells with Cytogenetic Abnormalities
Authors: Hida Kyoko , Hida Yasuhiro , Amin Dhara N. , Flint Alan F. , Panigrahy Dipak , Morton Cynthia C. , Klagsbrun Michael
Published: September 2005

Tumor angiogenesis is necessary for solid tumor progression and metastasis. Tumor blood vessels have been shown to differ from normal counterparts, for example, by changes in morphology. An important concept in tumor angiogenesis is that tumor endothelial cells are assumed to be genetically normal, although these endothelial cells are structurally and functionally abnormal. However, we hypothesized that given the phenotypic differences between tumor and normal blood vessels, there may be genotypic alterations as well. Mouse endothelial cells were isolated from two different human tumor xenografts, melanoma and liposarcoma, and from two normal endothelial cell counterparts, skin and adipose. Tumor-associated endothelial cells expressed typical endothelial cell markers, such as CD31. They had relatively large, heterogeneous nuclei. Unexpectedly, tumor endothelial cells were cytogenetically abnormal. Fluorescence in situ hybridization (FISH) analysis showed that freshly isolated uncultured tumor endothelial cells were aneuploid and had abnormal multiple centrosomes. The degree of aneuploidy was exacerbated by passage in culture. Multicolor FISH indicated that the structural chromosomal aberrations in tumor endothelial cells were heterogeneous, indicating that the cytogenetic alterations were not clonal. There was no evidence of human tumor-derived chromosomal material in the mouse tumor endothelial cells. In marked contrast, freshly isolated normal skin and adipose endothelial cells were diploid, had normal centrosomes, and remained cytogenetically stable in culture even up to 20 passages. FISH analysis of tumor sections also showed endothelial cell aneuploidy. We conclude that tumor endothelial cells can acquire cytogenetic abnormalities while in the tumor microenvironment.
A Major Role for Mitotic cdc2 Kinase Inactivation in the Establishment of the Mitotic DNA Damage Checkpoint
Authors: Bayart Emilie , Grigorieva Olga , Leibovitch Serge , Onclercq-Delic Rosine , Amor-Guéret Mounira
Published: September 2005

Cdc2 kinase is inactivated when DNA damage occurs during the spindle assembly checkpoint. Here, we show that the level of mitotic Bloom syndrome protein phosphorylation reflects the level of cdc2 activity. A complete inactivation of cdc2 by either introduction of DNA double-strand breaks or roscovitine treatment prevents exit from mitosis. Thus, mitotic cdc2 inactivation plays a major role in the establishment of the mitotic DNA damage checkpoint. In response to mitotic cdc2 inactivation, the M/G1 transition is delayed after releasing the drug block in nonmalignant cells, whereas tumor cells exit mitosis without dividing and rereplicate their DNA, which results in mitotic catastrophe. This opens the way for new chemotherapeutic strategies.
Dendritic Cells Strongly Boost the Antitumor Activity of Adoptively Transferred T Cells
In vivo
Authors: Lou Yanyan , Wang Gang , Lizée Gregory , Kim Grace J. , Finkelstein Steven E. , Feng Chiguang , Restifo Nicholas P. , Hwu Patrick
Published: September 2005

Dendritic cells (DCs) have been well characterized for their ability to initiate cell-mediated immune responses by stimulating naive T cells. However, the use of DCs to stimulate antigen-activated T cells in vivo has not been investigated. In this study, we determined whether DC vaccination could improve the efficacy of activated, adoptively transferred T cells to induce an enhanced antitumor immune response. Mice bearing B16 melanoma tumors expressing the gp100 tumor antigen were treated with cultured, activated T cells transgenic for a T-cell receptor specifically recognizing gp100, with or without concurrent peptide-pulsed DC vaccination. In this model, antigen-specific DC vaccination induced cytokine production, enhanced proliferation, and increased tumor infiltration of adoptively transferred T cells. Furthermore, the combination of DC vaccination and adoptive T-cell transfer led to a more robust antitumor response than the use of each treatment individually. Collectively, these findings illuminate a new potential application for DCs in the in vivo stimulation of adoptively transferred T cells and may be a useful approach for the immunotherapy of cancer.
PTEN Up-Regulates the Tumor Metastasis Suppressor Gene
Drg-1
in Prostate and Breast Cancer
Authors: Bandyopadhyay Sucharita , Pai Sudha K. , Hirota Shigeru , Hosobe Sadahiro , Tsukada Taisei , Miura Kunio , Takano Yukio , Saito Ken , Commes Therese , Piquemal David , Watabe Misako , Gross Steven , Wang Ying , Huggenvik Jodi , Watabe Kounosuke
Published: September 2005

PTEN (phosphatase and tensin homologue deleted on chromosome 10) has been shown to be inactivated in a wide variety of cancers, and the role of this gene as a tumor suppressor has been well established. On the other hand, results of recent animal studies as well as clinical evidence indicate that PTEN is also involved in tumor metastasis suppression. Although PTEN is known to play a key role in controlling cell growth and apoptosis, how PTEN exerts the metastasis suppressor function remains largely unknown. Recently, a microarray analysis identified the Drg-1 gene (differentiation related gene 1) as one of the potential targets of PTEN. The Drg-1 gene has been shown to suppress tumor metastasis in animal models of prostate and colon cancer, and the expression of this gene is significantly reduced with advancement of prostate and breast cancers in clinical setting. In this study, we explored the possibility that PTEN controls tumor metastasis by regulating the expression of the Drg-1 gene. Our results indicate that overexpression of PTEN significantly augments the endogenous expression of Drg-1 protein, whereas inhibition of PTEN by small interfering RNA decreases Drg-1 in a dose- and time-dependent manner. We also found that the control of the Drg-1 gene by PTEN seems to be at the transcriptional level, and that a phospho-Akt inhibitor restores the Drg-1 expression, indicating that PTEN controls Drg-1 by an Akt-dependent pathway. Consistent with these results, our immunohistochemical analysis revealed that PTEN expression correlates significantly with Drg-1 in both prostate and breast cancer cases. Furthermore, combination of the two markers, PTEN and Drg-1, emerged as a significantly better predictor of prostate and breast cancer patient survival than either marker alone.
Regulation of α-Fetoprotein by Nuclear Factor-κB Protects Hepatocytes from Tumor Necrosis Factor-α Cytotoxicity during Fetal Liver Development and Hepatic Oncogenesis
Authors: Cavin Lakita G. , Venkatraman Manickam , Factor Valentina M. , Kaur Swayamjot , Schroeder Insa , Mercurio Frank , Beg Amer A. , Thorgeirsson Snorri S. , Arsura Marcello
Published: September 2005

Nuclear factor-κB (NF-κB) plays a critical role during fetal liver development and hepatic oncogenesis. Here, we have assessed whether NF-κB activity is required for murine hepatocellular carcinoma cell survival. We show that adenoviral-mediated inhibition of inhibitor of NF-κB kinase-β (IKK-2) activity in hepatocellular carcinomas derived from transforming growth factor (TGF)-α/c-myc bitransgenic mice leads to inhibition of NF-κB and promotes tumor necrosis factor (TNF)-α–mediated cell death of malignant hepatocytes but not the surrounding peritumorous tissue. Induction of apoptosis is accompanied by inhibition of Bcl-XL and XIAP, two pro-survival NF-κB target genes. In addition, we have identified the α-fetoprotein (AFP) as a novel downstream target of NF-κB. We show that repression of IKK-2 activity in hepatocellular carcinomas promotes down-regulation of AFP gene expression. Likewise, genetic disruption of the RelA subunit results in reduced AFP gene expression during embryonic liver development, at a time in which fetal hepatocytes are sensitized to TNF-α–mediated cell killing. In this regard, we show that AFP inhibits TNF-α–induced cell death of murine hepatocellular carcinomas through association with TNF-α and inhibition of TNFRI signaling. Thus, NF-κB-mediated regulation of AFP gene expression during liver tumor formation and embryonic development of the liver constitutes a potential novel mechanism used by malignant and fetal hepatocytes to evade immune surveillance.
CYP3A4
,
CYP3A5
, and
CYP3A43
Genotypes and Haplotypes in the Etiology and Severity of Prostate Cancer
Authors: Zeigler-Johnson Charnita , Friebel Tara , Walker Amy H. , Wang Yiting , Spangler Elaine , Panossian Saarene , Patacsil Margerie , Aplenc Richard , Wein Alan J. , Malkowicz S. Bruce , Rebbeck Timothy R.
Published: September 2005

The CYP3A genes reside on chromosome 7q21 in a multigene cluster. The enzyme products of CYP3A4 and CYP3A43 are involved in testosterone metabolism. CYP3A4 and CYP3A5 have been associated previously with prostate cancer occurrence and severity. To comprehensively examine the effects of these genes on prostate cancer occurrence and severity, we studied 622 incident prostate cancer cases and 396 controls. Substantial and race-specific linkage disequilibrium was observed between CYP3A4 and CYP3A5 in both races but not between other pairs of loci. We found no association of CYP3A5 genotypes with prostate cancer or disease severity. CYP3A43*3 was associated with family history-positive prostate cancer (age- and race-adjusted odds ratio = 5.86, 95% confidence interval, 1.10–31.16). CYP3A4*1B was associated inversely with the probability of having prostate cancer in Caucasians (age-adjusted odds ratio = 0.54, 95% confidence interval, 0.32–0.94). We also observed significant interactions among these loci associated with prostate cancer occurrence and severity. There were statistically significant differences in haplotype frequencies involving these three genes in high-stage cases (P < 0.05) compared with controls. The observation that CYP3A4 and CYP3A43 were associated with prostate cancer, are not in linkage equilibrium, and are both involved in testosterone metabolism, suggest that both CYP3A4*1B and CYP3A43*3 may influence the probability of having prostate cancer and disease severity.
Maspin Expression Is Transactivated by p63 and Is Critical for the Modulation of Lung Cancer Progression
Authors: Kim Sejin , Han Joungho , Kim Jhingook , Park Chaehwa
Published: September 2005

Maspin inhibits metastasis of some cancer cells, and clinical studies have identified correlations between maspin loss and poor prognosis in several cancer types. Maspin was found to be significantly overexpressed in lung cancer samples as compared with matched normal lung tissues. However, the regulatory mechanism of maspin expression remains unclear. We show here that differential expression of maspin in carcinoma-derived lung cancer cells is regulated at the transcriptional level. We found that p63 is a critical factor for the transcription of maspin, which is lost in highly invasive cancer cells such as NCI-H157, NCI-322, and NCI-358. No correlation was found between maspin expression and the previously associated transcription factors, p53, Ets1, and Pdef. Instead, maspin expression was strictly dependent on the presence of p63 in lung cancer tissues (P < 0.001) and in the tested cell lines. Transient expression of p63 transactivated the maspin promoter with remarkable fold changes in cells expressing the TAp63, suggesting that TAp63 might be a novel stimulator of the maspin promoter in lung cancer. We have also demonstrated the binding of p63 protein to a previously identified p53-binding site on the maspin promoter by gel shift and chromatin immunoprecipitation assays. In tumor tissues, maspin expression was associated with lymph node involvement (P = 0.035) and tumor stage (P = 0.063) in all tested cases, except squamous carcinoma. In terms of function, ectopic expression of maspin inhibited cell invasion in squamous carcinoma as well as adenocarcinoma. Taken together, these results define maspin as a new molecular target of p63 that eventually inhibits the invasion of lung cancer.
C-Type Lectin-Like Molecule-1
Authors: Bakker Alexander B. H. , van den Oudenrijn Sonja , Bakker Arjen Q. , Feller Nicole , van Meijer Marja , Bia Judith A. , Jongeneelen Mandy A. C. , Visser Therese J. , Bijl Nora , Geuijen Cecilia A. W. , Marissen Wilfred E. , Radosevic Katarina , Throsby Mark , Schuurhuis Gerrit Jan , Ossenkoppele Gert J. , de Kruif John , Goudsmit Jaap , Kruisbeek Ada M.
Published: September 2005

Acute myeloid leukemia (AML) has a poor prognosis due to treatment-resistant relapses. A humanized anti-CD33 antibody (Mylotarg) showed a limited response rate in relapsed AML. To discover novel AML antibody targets, we selected a panel of single chain Fv fragments using phage display technology combined with flow cytometry on AML tumor samples. One selected single chain Fv fragment broadly reacted with AML samples and with myeloid cell lineages within peripheral blood. Expression cloning identified the antigen recognized as C-type lectin-like molecule-1 (CLL-1), a previously undescribed transmembrane glycoprotein. CLL-1 expression was analyzed with a human anti-CLL-1 antibody that was generated from the single chain Fv fragment. CLL-1 is restricted to the hematopoietic lineage, in particular to myeloid cells present in peripheral blood and bone marrow. CLL-1 is absent on uncommitted CD34+/CD38− or CD34+/CD33− stem cells and present on subsets of CD34+/CD38+ or CD34+/CD33+ progenitor cells. CLL-1 is not expressed in any other tissue. In contrast, analysis of primary AMLs demonstrated CLL-1 expression in 92% (68 of 74) of the samples. As an AML marker, CLL-1 was able to complement CD33, because 67% (8 of 12) of the CD33− AMLs expressed CLL-1. CLL-1 showed variable expression (10–60%) in CD34+ cells in chronic myelogenous leukemia and myelodysplastic syndrome but was absent in 12 of 13 cases of acute lymphoblastic leukemia. The AML reactivity combined with the restricted expression on normal cells identifies CLL-1 as a novel potential target for AML treatment.
A Gene Expression Signature Associated with Metastatic Outcome in Human Leiomyosarcomas
Authors: Lee Yin-Fai , John Megan , Falconer Alison , Edwards Sandra , Clark Jeremy , Flohr Penny , Roe Toby , Wang Rubin , Shipley Janet , Grimer Robert J. , Mangham D. Chas , Thomas J. Meirion , Fisher Cyril , Judson Ian , Cooper Colin S.
Published: September 2005

Metastasis is a major factor associated with poor prognosis in cancer, but little is known of its molecular mechanisms. Although the clinical behavior of soft tissue sarcomas is highly variable, few reliable determinants of outcome have been identified. New markers that predict clinical outcome, in particular the ability of primary tumors to develop metastatic tumors, are urgently needed. Here, we have chosen leiomyosarcoma as a model for examining the relationship between gene expression profile and the development of metastasis in soft tissue sarcomas. Using cDNA microarray, we have identified a gene expression signature associated with metastasis in sarcoma that allowed prediction of the future development of metastases of primary tumors (Kaplan-Meier analysis P = 0.001). Our finding may aid the tailoring of therapy for individual sarcoma patients, where the aggressiveness of treatment is affected by the predicted outcome of disease.
Cyclooxygenase 2-Dependent Expression of Survivin Is Critical for Apoptosis Resistance in Non-Small Cell Lung Cancer
Authors: Krysan Kostyantyn , Dalwadi Harnisha , Sharma Sherven , Põld Mehis , Dubinett Steven
Published: September 2005

Elevated tumor cyclooxygenase 2 (COX-2) expression is associated with increased angiogenesis, tumor invasion, and promotion of tumor cell resistance to apoptosis. In our previous studies using non-small cell lung cancer (NSCLC) cell lines constitutively expressing COX-2 cDNA in sense and antisense orientations, we demonstrated that constitutive overexpression of COX-2 leads to stabilization of the inhibitor of apoptosis protein survivin resulting in the elevated apoptosis resistance of COX-2–overexpressing cells. Genetic or pharmacologic suppression of COX-2 activity increased proteasomal degradation of survivin and cellular response to apoptosis induction. Our data show that expression of survivin in non-small cell lung cancer cells can be significantly down-regulated by RNA interference. Whereas COX-2–overexpressing NSCLC cells have significantly higher apoptosis resistance than the parental cells, inhibition of survivin expression by small interfering RNA decreases apoptosis resistance to the level of the parental non-small cell lung cancer. We conclude that COX-2-dependent expression of survivin is critical for apoptosis resistance in non-small cell lung cancer.
Convection-Enhanced Delivery of Tumor Necrosis Factor-Related Apoptosis-Inducing Ligand with Systemic Administration of Temozolomide Prolongs Survival in an Intracranial Glioblastoma Xenograft Model
Authors: Saito Ryuta , Bringas John R. , Panner Amith , Tamas Matyas , Pieper Russell O. , Berger Mitchel S. , Bankiewicz Krystof S.
Published: September 2005

Although tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is a potent activator of cell death, preferentially killing neoplastic cells over normal cells, the efficacy of TRAIL for the treatment of glioma might be limited due to cellular resistance and, importantly, poor distribution after systemic administration. TRAIL and temozolomide (TMZ) were recently shown to have a synergistic antitumor effect against U87MG glioma cells in vitro. Convection-enhanced delivery (CED) can effectively distribute TRAIL protein throughout a brain tumor mass. In this study, we evaluated CED of TRAIL, alone and in conjunction with systemic TMZ administration, for antitumor efficacy. CED of TRAIL demonstrated safe and effective distribution in both normal brain and a U87MG intracranial xenograft model. Individually, both CED of TRAIL and systemic TMZ administration prolonged survival in tumor-bearing rats. However, the combination of these two treatments was significantly more effective than either treatment alone. CED of TRAIL in conjunction with systemic TMZ treatment is a promising strategy for the treatment of malignant gliomas.
Characterization of a Carcinogenesis Rat Model of Ovarian Preneoplasia and Neoplasia
Authors: Stewart Sherri L. , Querec Troy D. , Ochman Alexander R. , Gruver Briana N. , Bao Rudi , Babb James S. , Wong Thang S. , Koutroukides Theodoros , Pinnola Aaron D. , Klein-Szanto Andres , Hamilton Thomas C. , Patriotis Christos
Published: September 2005

Animal models of ovarian cancer are crucial for understanding the pathogenesis of the disease and for testing new treatment strategies. A model of ovarian carcinogenesis in the rat was modified and improved to yield ovarian preneoplastic and neoplastic lesions that pathogenetically resemble human ovarian cancer. A significantly lower dose (2 to 5 μg per ovary) of 7,12-dimethylbenz(a)anthracene (DMBA) was applied to the one ovary to maximally preserve its structural integrity. DMBA-induced mutagenesis was additionally combined with repetitive gonadotropin hormone stimulation to induce multiple cycles of active proliferation of the ovarian surface epithelium. Animals were treated in three arms of different doses of DMBA alone or followed by hormone administration. Comparison of the DMBA-treated ovaries with the contralateral control organs revealed the presence of epithelial cell origin lesions at morphologically distinct stages of preneoplasia and neoplasia. Their histopathology and path of dissemination to other organs are very similar to human ovarian cancer. Hormone cotreatment led to an increased lesion severity, indicating that gonadotropins may promote ovarian cancer progression. Point mutations in the Tp53 and Ki-Ras genes were detected that are also characteristic of human ovarian carcinomas. Additionally, an overexpression of estrogen and progesterone receptors was observed in preneoplastic and early neoplastic lesions, suggesting a role of these receptors in ovarian cancer development. These data indicate that this DMBA animal model gives rise to ovarian lesions that closely resemble human ovarian cancer and it is adequate for additional studies on the mechanisms of the disease and its clinical management.
Interferon γ Enhances the Effectiveness of Tumor Necrosis Factor-Related Apoptosis–Inducing Ligand Receptor Agonists in a Xenograft Model of Ewing’s Sarcoma
Authors: Merchant Melinda S. , Yang Xuezhong , Melchionda Fraia , Romero Maria , Klein Ruth , Thiele Carol J. , Tsokos Maria , Kontny H. Udo , Mackall Crystal L.
Published: September 2005

Tumor necrosis factor–related apoptosis-inducing ligand (TRAIL) induces selective apoptosis in a variety of tumors, including most cell lines derived from Ewing’s sarcoma family of tumors, an aggressive sarcoma that afflicts children and young adults. To determine the in vivo efficacy of TRAIL receptor agonists in Ewing’s sarcoma family of tumors, mice with orthotopic xenografts were treated with anti-TRAIL-R2 monoclonal antibody or TRAIL/Apo2L in a model that can identify effects on both primary tumors and metastases. Administration of either agonist slowed tumor growth in 60% of animals and induced durable remissions in 11 to 19% but did not alter the incidence of metastatic disease. Response rates were not improved by concurrent doxorubicin treatment. Cells recovered from both TRAIL receptor agonist–treated and nontreated tumors were found to be resistant to TRAIL-induced death in vitro unless pretreated with interferon (IFN) γ. This resistance coincided with a selective down-regulation of TRAIL receptor expression on tumor cells. In vivo treatment with IFNγ increased tumor expression of TRAIL receptors and caspase 8, but did not increase the antitumor effect of TRAIL receptor agonists on primary tumors. However, IFNγ treatment alone or in combination with a TRAIL receptor agonist significantly decreased the incidence of metastatic disease and the combination of TRAIL receptor agonist therapy with IFNγ-mediated impressive effects on both primary tumors and metastatic disease. These data demonstrate that in vivo growth favors TRAIL resistance but that TRAIL receptor agonists are active in Ewing’s sarcoma family of tumors and that the combination of TRAIL receptor agonists with IFNγ is a potent regimen in this disease capable of controlling both primary and metastatic tumors.
The Novel Sequence-Specific DNA Cross-Linking Agent SJG-136 (NSC 694501) Has Potent and Selective
In vitro
Cytotoxicity in Human B-Cell Chronic Lymphocytic Leukemia Cells with Evidence of a p53-Independent Mechanism of Cell Kill
Authors: Pepper Christopher J. , Hambly Rachel M. , Fegan Christopher D. , Delavault Patrick , Thurston David E.
Published: September 2005

SJG-136 (NSC 694501) is a novel DNA cross-linking agent that binds in a sequence-selective manner in the minor groove of the DNA helix. It is structurally novel compared with other clinically used DNA cross-linking agents and has exhibited a unique multilog differential pattern of activity in the NCI 60-cell line screen (i.e., is COMPARE negative to other cross-linking agents). Given this profile, we undertook a preclinical evaluation of SJG-136 in primary tumor cells derived from 34 B-cell chronic lymphocytic leukemia (B-CLL) patients. SJG-136 induced apoptosis in all of the B-CLL samples tested with a mean LD50 value (the concentration of drug required to kill 50% of the cells) of 9.06 nmol/L. Its cytotoxicity was undiminished in B-CLL cells derived from patients treated previously, those with unmutated VH genes, and those with p53 mutations (P = 0.17; P = 0.63; P = 0.42, respectively). SJG-136-induced apoptosis was associated with the activation of caspase-3 that could be partially abrogated by the caspase-9 inhibitor Z-LEHD-FMK. Furthermore, SJG-136 did not trigger the phosphorylation of p53 or the up-regulation of GADD45 expression in B-CLL cells whereas the cross-linking agent chlorambucil elicited both of these effects. This suggests that SJG-136 cross-linking adducts are not subject to p53-mediated DNA excision repair mechanisms in B-CLL cells. Taken together, these data demonstrate a novel mechanism of action for SJG-136 that appears to circumvent the effects of poor prognostic markers. This unique cytotoxicity profile warrants further investigation and supports the evaluation of this agent in Phase I clinical trials for patients with B-CLL.
Homeobox D10 Induces Phenotypic Reversion of Breast Tumor Cells in a Three-Dimensional Culture Model
Authors: Carrio Meritxell , Arderiu Gemma , Myers Connie , Boudreau Nancy J.
Published: September 2005

Homeobox (Hox) genes are master regulatory genes that direct organogenesis and maintain differentiated tissue function. We previously reported that HoxD10 helps to maintain a quiescent, differentiated phenotype in endothelial cells by suppressing expression of genes involved in remodeling the extracellular matrix and cell migration. Here we investigated whether HoxD10 could also promote or maintain a differentiated phenotype in epithelial cells. We observed that HoxD10 expression is progressively reduced in epithelial cells as malignancy increases in both breast and endometrial tumors. Retroviral gene transfer to restore expression of HoxD10 in the malignant breast tumor cells MDA-MB-231 significantly impaired migration, and when these cells were cultured in a three-dimensional laminin-rich basement membrane (3DlrBM) model, they formed polarized, acinar structures. This phenotypic reversion was accompanied by decreased α3 integrin expression and reduced proliferation. Importantly, expression of HoxD10 in the MDA-MB-231 cells inhibited their ability to form tumors in mouse xenografts. Taken together, our results suggest that HoxD10 has tumor-suppressive functions for mammary epithelial cells.
Invasive Potential Induced under Long-Term Oxidative Stress in Mammary Epithelial Cells
Authors: Mori Kazunori , Shibanuma Motoko , Nose Kiyoshi
Published: September 2005

Although the causal relationship between chronic inflammation and carcinogenesis has long been discussed, the molecular basis of the relation is poorly understood. In the present study, we focused on reactive oxygen species (ROS) and their signals under inflammatory conditions leading to the carcinogenesis of epithelial cells and found that repeated treatment with a low dose of H2O2 (0.2 mmol/L) for periods of 2 to 4 days caused a phenotypic conversion of mouse NMuMG mammary epithelial cells from epithelial to fibroblast-like as in malignant transformation. The phenotypic conversion included the dissolution of cell-cell contacts, redistribution of E-cadherin in the cytoplasm, and up-regulation of a set of integrin family members (integrin α2, α6, and β3) and matrix metalloproteinases (MMPs; MMP-3, -10, and -13), as analyzed using Northern blot analysis and quantitative reverse transcription-PCR. Gelatin zymography indicated post-transcriptional activation of gelatinases, including MMP-2 and -9. In parallel, p38 mitogen-activated protein kinase and extracellular signal-regulated kinase 1/2 were activated, which contributed to the induction of MMP-13, and a glutathione S-transferase pull-down assay showed the activation of a small GTPase, Rac1. Surprisingly, the prolonged oxidative treatment was sufficient to induce all of the aforementioned events. Most importantly, depending on the MMP activities, the epithelial cells exposed to oxidative conditions eventually acquired invasiveness in a reconstituted model system with a Matrigel invasion chamber containing normal fibroblasts at the bottom, providing the first substantial evidence supporting the direct role of ROS signals in the malignant transformation of epithelial cells.
Membrane-Associated and Secreted Genes in Breast Cancer
Authors: Stitziel Nathan O. , Mar Brenton G. , Liang Jie , Westbrook Carol A.
Published: September 2005

The identification of membrane-associated and secreted genes that are differentially expressed is a useful step in defining new targets for the diagnosis and treatment of cancer. Extracting information on the subcellular localization of genes represented on DNA microarrays is difficult and is limited by the incomplete sequence and annotation that is available in existing databases. Here we combine a biochemical and bioinformatic approach to identify membrane-associated and secreted genes expressed in the MCF-7 breast cancer cell line. Our approach is based on the analysis of differential hybridization levels of RNAs that have been physically separated by virtue of their association with polysomes on the endoplasmic reticulum. This approach is specifically applicable to oligonucleotide microarrays such as Affymetrix, which use single-color hybridization instead of dual-color competitive hybridizations. Assignment to membrane-associated and secreted class membership is based on both the differential hybridization levels and an expression threshold, which are calculated empirically from data collected on a reference set of known cytoplasmic and membrane proteins. This method enabled the identification of 755 membrane-associated and secreted probe sets expressed in MCF-7 cells for which this annotation did not previously exist. The data were used to filter a previously reported expression dataset to identify membrane-associated and secreted genes which are associated with poor prognosis in breast cancer and represent potential targets for diagnosis and treatment. The approach reported here should provide a useful tool for the analysis of gene expression patterns, identifying membrane-associated or secreted genes with biological relevance that have the potential for clinical applications in diagnosis or treatment.
A Recurrent Chromosome Breakpoint in Breast Cancer at the
NRG1
/
Neuregulin 1
/
Heregulin
Gene
Authors: Huang Huai-En , Chin Suet-Feung , Ginestier Christophe , Bardou Valérie-Jeanne , Adélaïde José , Iyer N. Gopalakrishna , Garcia Maria J. , Pole Jessica C. , Callagy Grace M. , Hewitt Stephen M. , Gullick William J. , Jacquemier Jocelyne , Caldas Carlos , Chaffanet Max , Birnbaum Daniel , Edwards Paul A. W.
Published: September 2005

Most studies of genomic rearrangements in common cancers have focused on regional gains and losses, but some rearrangements may break within specific genes. We previously reported that five breast cancer cell lines have chromosome translocations that break in the NRG1 gene and that could cause abnormal NRG1 expression. NRG1 encodes the Neuregulins 1 (formerly the Heregulins), ligands for members of the ErbB/epidermal growth factor-receptor family, which includes ErbB2/HER2. We have now screened for breaks at NRG1 in paraffin sections of breast tumors. Tissue microarrays were screened by fluorescence in situ hybridization, with hybridization probes proximal and distal to the expected breakpoints. This screen detects breaks but does not distinguish between translocation or deletion breakpoints. The screen was validated with array-comparative genomic hybridization on a custom 8p12 high-density genomic array to detect a lower copy number of the sequences that were lost distal to the breaks. We also precisely mapped the breaks in five tumors with different hybridization probes. Breaks in NRG1 were detected in 6% (19 of 323) of breast cancers and in some lung and ovarian cancers. In an unselected series of 213 cases with follow-up, breast cancers where the break was detected tended to be high-grade (65% grade III compared with 28% of negative cases). They were, like breast tumors in general, mainly ErbB2 low (11 of 13 were low) and estrogen receptor positive (11 of 13 positive).
Gene-Environment Interaction Signatures by Quantitative mRNA Profiling in Exfoliated Buccal Mucosal Cells
Authors: Spivack Simon D. , Hurteau Gregory J. , Jain Ritu , Kumar Shalini V. , Aldous Kenneth M. , Gierthy John F. , Kaminsky Laurence S.
Published: September 2005

Exfoliated cytologic specimens from mouth (buccal) epithelium may contain viable cells, permitting assay of gene expression for direct and noninvasive measurement of gene-environment interactions, such as for inhalation (e.g., tobacco smoke) exposures. We determined specific mRNA levels in exfoliated buccal cells collected by cytologic brush, using a recently developed RNA-specific real-time quantitative reverse transcription-PCR strategy. In a pilot study, metabolic activity of exfoliated buccal cells was verified by 3-[4,5-dimethylthiazol-2-yl]-2,5- diphenyltetrazolium assay in vitro. Transcriptional activity was observed, after timed in vivo exposure to mainstream tobacco smoke resulted in induction of CYP1B1 in serially collected buccal samples from the one subject examined. For a set of 11 subjects, mRNA expression of nine genes encoding carcinogen- and oxidant-metabolizing enzymes qualitatively detected in buccal cells was then shown to correlate with that in laser-microdissected lung from the same individuals (χ2 = 52.91, P < 0.001). Finally, quantitative real-time reverse transcription-PCR assays for seven target gene (AhR, CYP1A1, CYP1B1, GSTM1, GSTM3, GSTP1, and GSTT1) and three reference gene [glyceraldehyde-3-phosphate dehydrogenase (GAPDH), β-actin, and 36B4] transcripts were performed on buccal specimens from 42 subjects. In multivariate analyses, gender, tobacco smoke exposure, and other factors were associated with the level of expression of CYP1B1, GSTP1, and other transcripts on a gene-specific basis, but substantial interindividual variability in mRNA expression remained unexplained. Within the power limits of this pilot study, gene expression signature was not clearly predictive of lung cancer case or control status. This noninvasive and quantitative method may be incorporated into high-throughput human applications for probing gene-environment interactions associated with cancer.
Granulocyte-Macrophage Colony-Stimulating Factor and Interleukin-2 Fusion cDNA for Cancer Gene Immunotherapy
Authors: Stagg John , Wu Jian Hui , Bouganim Nathaniel , Galipeau Jacques
Published: September 2005

Genetic engineering of tumor cells to express both granulocyte-macrophage colony-stimulating factor (GM-CSF) and interleukin (IL)-2 can induce synergistic immune antitumor effects. Paradoxically, the combination has also been reported to down-regulate certain immune functions, highlighting the unpredictability of dual cytokine use. We hypothesized that a GM-CSF and IL-2 fusion transgene (GIFT) could circumvent such limitations yet preserve synergistic features. We designed a fusion cDNA of murine GM-CSF and IL-2. Protein structure computer modeling of GIFT protein predicted for intact ligand binding domains for both cytokines. B16 mouse melanoma cells were gene modified to express GIFT (B16GIFT), and these cells were unable to form tumors in C57bl/6 mice. Irradiated B16GIFT whole-cell tumor vaccine could also induce absolute protective immunity against challenge by live B16 cells. In mice with established melanoma, B16GIFT therapeutic cellular vaccine significantly improved tumor-free survival when compared with B16 expressing both IL-2 and GM-CSF. We show that GIFT induced a significantly greater tumor site recruitment of macrophages than combined GM-CSF and IL-2 and that macrophage recruitment arises from novel chemotactic feature of GIFT. In contrast to suppression by GM-CSF of natural killer (NK) cell recruitment despite coexpression of IL-2, GIFT leads to significant functional NK cell infiltration as confirmed in NK-defective beige mice. In conclusion, we demonstrated that a fusion between GM-CSF and IL-2 can invoke greater antitumor effect than both cytokines in combination, and novel immunobiological properties can arise from such chimeric constructs.
Large-Scale Association Study Identifies
ICAM
Gene Region as Breast and Prostate Cancer Susceptibility Locus
Authors: Kammerer Stefan , Roth Richard B. , Reneland Richard , Marnellos George , Hoyal Carolyn R. , Markward Nathan J. , Ebner Florian , Kiechle Marion , Schwarz-Boeger Ulrike , Griffiths Lyn R. , Ulbrich Christian , Chrobok Korbinian , Forster Gerhard , Praetorius Georg M. , Meyer Peter , Rehbock Joachim , Cantor Charles R. , Nelson Matthew R. , Braun Andreas
Published: September 2005

We conducted a large-scale association study to identify genes that influence nonfamilial breast cancer risk using a collection of German cases and matched controls and >25,000 single nucleotide polymorphisms located within 16,000 genes. One of the candidate loci identified was located on chromosome 19p13.2 [odds ratio (OR) = 1.5, P = 0.001]. The effect was substantially stronger in the subset of cases with reported family history of breast cancer (OR = 3.4, P = 0.001). The finding was subsequently replicated in two independent collections (combined OR = 1.4, P < 0.001) and was also associated with predisposition to prostate cancer in an independent sample set of prostate cancer cases and matched controls (OR = 1.4, P = 0.002). High-density single nucleotide polymorphism mapping showed that the extent of association spans 20 kb and includes the intercellular adhesion molecule genes ICAM1, ICAM4, and ICAM5. Although genetic variants in ICAM5 showed the strongest association with disease status, ICAM1 is expressed at highest levels in normal and tumor breast tissue. A variant in ICAM5 was also associated with disease progression and prognosis. Because ICAMs are suitable targets for antibodies and small molecules, these findings may not only provide diagnostic and prognostic markers but also new therapeutic opportunities in breast and prostate cancer.