bluuebunny/crossref_metadata_2025 huggingface dataset:
Data from Bobel-24 and Derivatives Induce Caspase-Independent Death in Pancreatic Cancer Regardless of Apoptotic Resistance
Authors: Parreño Matilde , Casanova Isolda , Céspedes María Virtudes , Vaqué Jose Pedro , Pavón Miguel Angel , Leon Javier , Mangues Ramon
Published: March 2024

Abstract
The poor prognosis of pancreatic cancer and poor sensitivity to current therapeutics, associated with resistance to apoptosis, urge the search for new drugs. We previously described the induction of caspase-independent mithochondrial death in leukemia cells by Bobel-24 (AM-24) and derivatives. Here, we explored whether these compounds induce a similar cytotoxicity in human pancreatic carcinoma cell lines (NP18, NP9, NP31, and NP29). Bobel-24 or Bobel-16 induced cytotoxicity and DNA synthesis inhibition in all cell lines and apoptosis in all lines, except for NP9. Caspase and/or poly(ADP-ribose) polymerase-1 (PARP-1) activity inhibition experiments showed that cytotoxicity was mainly induced through apoptosis in NP18 and through a caspase-independent process in NP9. Moreover, in NP29 or NP31 cell lines, both caspase-dependent and caspase-independent cell death mechanisms coexisted. Cell death was associated with reactive oxygen species (ROS) production, mitochondrial depolarization, cytochrome c and apoptosis-inducing factor (AIF) release, AIF nuclear translocation, and lysosomal cathepsin release. Inhibition of ROS production, mitochondrial pore permeability, PARP-1, or phospholipase A2 partially prevented cell death. Moreover, cathepsin B inhibition or down-regulation by small interfering RNA partially blocked cell death. In conclusion, Bobel-24 and derivatives trigger caspase-independent lysosomal and mitochondrial death in all tested human pancreatic cancer lines, irrespective of their degree of apoptotic sensitivity, becoming the only active cytotoxic mechanism in the apoptosis-resistant NP9 line. This mechanism may overcome the resistance to apoptosis observed in pancreatic carcinoma when treated with current genotoxic drugs. [Cancer Res 2008;68(15):6313–23]
Data from Potent In vitro and In vivo Activity of an Fc-Engineered Anti-CD19 Monoclonal Antibody against Lymphoma and Leukemia
Authors: Horton Holly M. , Bernett Matthew J. , Pong Erik , Peipp Matthias , Karki Sher , Chu Seung Y. , Richards John O. , Vostiar Igor , Joyce Patrick F. , Repp Roland , Desjarlais John R. , Zhukovsky Eugene A.
Published: March 2024

Abstract
CD19 is a pan B-cell surface receptor expressed from pro–B-cell development until its down-regulation during terminal differentiation into plasma cells. CD19 represents an attractive immunotherapy target for cancers of lymphoid origin due to its high expression levels on the vast majority of non–Hodgkin's lymphomas and some leukemias. A humanized anti-CD19 antibody with an engineered Fc domain (XmAb5574) was generated to increase binding to Fcγ receptors on immune cells and thus increase Fc-mediated effector functions. In vitro, XmAb5574 enhanced antibody-dependent cell-mediated cytotoxicity 100-fold to 1,000-fold relative to an anti-CD19 IgG1 analogue against a broad range of B-lymphoma and leukemia cell lines. Furthermore, XmAb5574 conferred antibody-dependent cell-mediated cytotoxicity against patient-derived acute lymphoblastic leukemia and mantle cell lymphoma cells, whereas the IgG1 analogue was inactive. XmAb5574 also increased antibody-dependent cellular phagocytosis and apoptosis. In vivo, XmAb5574 significantly inhibited lymphoma growth in prophylactic and established mouse xenograft models, and showed more potent antitumor activity than its IgG1 analogue. Comparisons with a variant incapable of Fcγ receptor binding showed that engagement of these receptors is critical for optimal antitumor efficacy. These results suggest that XmAb5574 exhibits potent tumor cytotoxicity via direct and indirect effector functions and thus warrants clinical evaluation as an immunotherapeutic for CD19+ hematologic malignancies. [Cancer Res 2008;68(19):8049–57]
Data from MicroRNAs 221 and 222 Bypass Quiescence and Compromise Cell Survival
Authors: Medina Ricardo , Zaidi Sayyed K. , Liu Chang-Gong , Stein Janet L. , vanWijnen Andre J. , Croce Carlo M. , Stein Gary S.
Published: March 2024

Abstract
MicroRNAs (miRNA) have tumor suppressive and oncogenic potential in human cancer, but whether and how miRNAs control cell cycle progression is not understood. To address this question, we carried out a comprehensive analysis of miRNA expression during serum stimulation of quiescent human cells. Time course analyses revealed that four miRNAs are up-regulated and >100 miRNAs are down-regulated, as cells progress beyond the G1-S phase transition. We analyzed the function of two up-regulated miRNAs (miR-221 and miR-222) that are both predicted to target the cell growth suppressive cyclin-dependent kinase inhibitors p27 and p57. Our results show that miR-221 and miR-222 both directly target the 3′ untranslated regions of p27 and p57 mRNAs to reduce reporter gene expression, as well as diminish p27 and p57 protein levels. Functional studies show that miR-221 and miR-222 prevent quiescence when elevated during growth factor deprivation and induce precocious S-phase entry, thereby triggering cell death. Thus, the physiologic up-regulation of miR-221 and miR-222 is tightly linked to a cell cycle checkpoint that ensures cell survival by coordinating competency for initiation of S phase with growth factor signaling pathways that stimulate cell proliferation. [Cancer Res 2008;68(8):2773–80]
Data from Human Adrenomedullin Up-regulates Interleukin-13 Receptor α2 Chain in Prostate Cancer In vitro and In vivo: A Novel Approach to Sensitize Prostate Cancer to Anticancer Therapy
Authors: Joshi Bharat H. , Leland Pamela , Calvo Alfonso , Green Jeffrey E. , Puri Raj K.
Published: March 2024

Abstract
Interleukin-13 (IL-13) receptor α2 (IL-13Rα2), a high-affinity IL-13 binding subunit and a tumor antigen, is amplified in a variety of human tumor cell lines and tumors in vivo. By cDNA microarray, we have shown that gene transfer of human and rat adrenomedullin (AM) up-regulates IL-13Rα2 in a human prostate tumor cell line. Here, we show that IL-13Rα2 mRNA and protein are also up-regulated in PC-3 prostate tumor cells by recombinant AM (rAM) and human synthetic AM peptide in a dose-dependent manner in vitro and in vivo in mouse prostate tumor model. The 8- to 10-fold up-regulation of IL-13Rα2 by rAM or AM peptide in prostate tumor cells in vitro and in vivo increased their sensitivity to IL-13PE cytotoxin consisting of IL-13 and a truncated form of Pseudomonas exotoxin. Immunodeficient mice with established prostate tumors transfected with AM or treated with AM peptide showed reduction in tumor size by intratumoral administration of IL-13PE in a dose-dependent manner. At the highest dose (three 100 μg/kg/d every alternate day), >70% reduction of tumor size was observed compared with controls (P ≤ 0.01). These results indicate that two completely unrelated hormones (AM and IL-13) are closely related to each other and that we have identified a novel role of AM in sensitizing certain types of prostate tumors to IL-13R–directed therapeutic agent. [Cancer Res 2008;68(22):9311–7]
Data from Molecular Mechanisms of Patupilone Resistance
Authors: Mozzetti Simona , Iantomasi Raffaella , De Maria Ilaria , Prislei Silvia , Mariani Marisa , Camperchioli Alessia , Bartollino Silvia , Gallo Daniela , Scambia Giovanni , Ferlini Cristiano
Published: March 2024

Abstract
Patupilone is an epothilone in advanced clinical development that has shown promising efficacy in heavily pretreated patients. This study aimed at characterizing the mechanisms of patupilone activity in resistant patients. To this end, we generated patupilone-resistant cells using two cellular models, the first characterized by high chemosensitivity and low class III β-tubulin (TUBB3) expression (A2780), and the second by low chemosensitivity and high TUBB3 expression (OVCAR-3). The obtained cell lines were named EPO3 and OVCAR-EPO, respectively. The same selection procedure was done in A2780 cells to generate a paclitaxel-resistant cell line (TAX50). Factors of resistance are expected to increase in the drug-resistant cell lines, whereas factors of drug sensitivity will be down-regulated. Using this approach, we found up-regulation of TUBB3 in TAX50, but not EPO3, cells, showing that TUBB3 mediates the resistance to paclitaxel but not to patupilone. Moreover, TUBB3 was a factor of patupilone sensitivity because OVCAR-EPO cells exhibited a dramatic reduction of TUBB3 and a concomitant sensitization to hypoxia and cisplatin-based chemotherapy. To identify the mechanisms underlying patupilone resistance, tubulin genes were sequenced, thereby revealing that a prominent mechanism of drug resistance is represented by point mutations in class I β-tubulin. Overall, these results suggest that paclitaxel and patupilone have nonoverlapping mechanisms of resistance, thus allowing the use of patupilone for those patients relapsing after paclitaxel-based chemotherapy. Furthermore, patupilone represents a promising first-line option for the treatment of high-risk ovarian cancer patients, who exhibit high TUBB3 levels and poor response to standard paclitaxel-platin chemotherapy. [Cancer Res 2008;68(24):10197–204]
Data from A Requirement for DICER to Maintain Full Promoter CpG Island Hypermethylation in Human Cancer Cells
Authors: Ting Angela H. , Suzuki Hiromu , Cope Leslie , Schuebel Kornel E. , Lee Byron H. , Toyota Minoru , Imai Kohzoh , Shinomura Yasuhisa , Tokino Takashi , Baylin Stephen B.
Published: March 2024

Abstract
Promoter hypermethylation is a prevalent phenomenon, found in virtually all cancer types studied thus far, and accounts for tumor suppressor gene silencing in the absence of genetic mutations. The mechanism behind the establishment and maintenance of such aberrant hypermethylation has been under intense study. Here, we have uncovered a link between aberrant gene silencing associated with promoter CpG island DNA methylation and the siRNA/miRNA processing enzyme, DICER, in human cancer cells. By comparing demethylated HCT116 colon cancer cells with HCT116 cells genetically rendered hypomorphic for DICER, we identified a group of epigenetically silenced genes that became reactivated in the absence of functional DICER. This reactivation is associated with a dramatic loss of localized promoter DNA hypermethylation. Thus, intact DICER is required to maintain full promoter DNA hypermethylation of select epigenetically silenced loci in human cancer cells. [Cancer Res 2008;68(8):2570–5]
Data from Identification of Transformation-Related Pathways in a Breast Epithelial Cell Model Using a Ribonomics Approach
Authors: Mazan-Mamczarz Krystyna , Hagner Patrick R. , Dai Bojie , Wood William H. , Zhang Yongqing , Becker Kevin G. , Liu Zhenqui , Gartenhaus Ronald B.
Published: March 2024

Abstract
The aberrant expression of many genes is a common feature in the malignant transformation of cells. In mammalian cells, posttranscriptional gene regulatory processes are emerging as critical determinants controlling gene expression both in physiologic and pathologic conditions. These regulatory mechanisms are directed primarily by the interaction of mRNAs with specific RNA-binding proteins (RBP). There is an emerging body of data demonstrating that two RBPs, AUF1 and HuR, can antagonistically affect the posttranscriptional fate of target mRNAs, as well as concurrently bind to common target transcripts. Employing MCT-1 oncogene-mediated transformation of immortalized breast epithelial MCF10A cells, we characterized the largely reciprocal association of these two RBPs with target mRNAs and their influence on protein expression vis-a-vis cellular transformation. Using a ribonomics approach, we identified mRNAs from cancer-related pathways whose association with AUF1 and/or HuR were altered when comparing immortalized with transformed MCF10A cells. Significantly, we were able to show that knockdown of HuR expression using RNA interference reduced anchorage-independent growth capacity in transformed MCF10A cells and decreased protein expression of a number of validated target genes. Our data show that the global alterations in binding of HuR and AUF1 with target transcripts have a critical role in posttranscriptional regulation of genes encoding proteins involved in breast epithelial cell transformation. These findings further support the feasibility of using a ribonomics approach for the identification of cancer-related pathways. [Cancer Res 2008;68(19):7730–5]
Data from Levels of SCS7/FA2H-Mediated Fatty Acid 2-Hydroxylation Determine the Sensitivity of Cells to Antitumor PM02734
Authors: Herrero Ana B. , Astudillo Alma M. , Balboa María A. , Cuevas Carmen , Balsinde Jesús , Moreno Sergio
Published: March 2024

Abstract
PM02734 is a novel synthetic antitumor drug that is currently in phase I clinical trials. To gain some insight into its mode of action, we used the yeast Saccharomyces cerevisiae as a model system. Treatment of S. cerevisiae with PM02734 rapidly induced necrosis-like cell death, as also found for mammalian cells treated with its close analogue kahalalide F. We have screened the complete set of 4,848 viable S. cerevisiae haploid deletion mutants to identify genes involved in sensitivity or resistance to PM02734. Forty-five percent of the 40 most sensitive strains identified had a role in intracellular vesicle trafficking, indicating that the drug severely affects this process. A mutant strain lacking the sphingolipid fatty acyl 2-hydroxylase Scs7 was found to be the most resistant to PM02734, whereas overexpression of Scs7 rendered the cells hypersensitive to PM02734. To validate these findings in human cells, we did small interfering RNA experiments and also overexpressed the Scs7 human homologue FA2H in human cancer cell lines. As in yeast, FA2H silencing turned the cells resistant to the drug, whereas FA2H overexpression led to an increased sensitivity. Moreover, exogenous addition of the 2-hydroxylated fatty acid 2-hydroxy palmitic acid to different human cell lines increased their sensitivity to the cytotoxic compound. Taken together, these results suggest that the cell membrane and, in particular, 2-hydroxy fatty acid–containing ceramides are important for PM02734 activity. These findings may have important implications in the development of PM02734 because tumor cells with high FA2H expression are expected to be particularly sensitive to this drug. [Cancer Res 2008;68(23):9779–87]
Data from Conditional Loss of Uterine Pten Unfailingly and Rapidly Induces Endometrial Cancer in Mice
Authors: Daikoku Takiko , Hirota Yasushi , Tranguch Susanne , Joshi Ayesha R. , DeMayo Francesco J. , Lydon John P. , Ellenson Lora H. , Dey Sudhansu K.
Published: March 2024

Abstract
Etiology of endometrial cancer (EMC) is not fully understood. Animal models with rapidly and spontaneously developing EMC will help explore mechanisms of cancer initiation and progression. Pten+/− mice are currently being used as a model to study EMC. These females develop atypical endometrial hyperplasia of which ∼20% progresses to EMC. In addition, tumors develop in other organs, complicating the use of this model to specifically study EMC. Here, we show that conditional deletion of endometrial Pten results in EMC in all female mice as early as age 1 month with myometrial invasion occurring by 3 months. In contrast, conditional deletion of endometrial p53 had no phenotype within this time frame. Whereas mice with endometrial Pten deletion had a life span of ∼5 months, mice with combined deletion of endometrial Pten and p53 had a shorter life span with an exacerbated disease state. Such rapid development of EMC from homozygous loss of endometrial Pten suggests that this organ is very sensitive to this tumor suppressor gene for tumor development. All lesions at early stages exhibited elevated Cox-2 and phospho-Akt levels, hallmarks of solid tumors. More interestingly, levels of two microRNAs miR-199a* and miR-101a that posttranscriptionally inhibit Cox-2 expression were down-regulated in tumors in parallel with Cox-2 up-regulation. This mouse model in which the loxP-Cre system has been used to delete endometrial Pten and/or p53 allows us to study in detail the initiation and progression of EMC. These mouse models have the added advantage because they mimic several features of human EMC. [Cancer Res 2008;68(14):5619–27]
Data from A Mutant Collagen XIII Alters Intestinal Expression of Immune Response Genes and Predisposes Transgenic Mice to Develop B-Cell Lymphomas
Authors: Tuomisto Anne , Sund Malin , Tahkola Jenni , Latvanlehto Anne , Savolainen Eeva-Riitta , Autio-Harmainen Helena , Liakka Annikki , Sormunen Raija , Vuoristo Jussi , West Anne , Lahesmaa Riitta , Morse Herbert C. , Pihlajaniemi Taina
Published: March 2024

Abstract
Epithelial cells of mucosal surfaces are critical for maintaining immune homeostasis by aiding in the discrimination of pathogenic and commensal microorganisms and modulating the activities of antigen-presenting cells and lymphocytes. Functional breakdowns resulting in chronic infection and inflammation are associated with the development of hematologic and solid neoplasms for which detailed pathogenetic mechanisms are poorly understood. Mice heterozygous for a transgene Col13a1del expressing a mutant collagen XIII developed clonal mature B-cell lineage lymphomas originating in mesenteric lymph nodes (MLN). The tumors were associated with T cells and macrophages. The incidence of disease was reduced 2-fold in transgenic mice raised under specific pathogen-free conditions, suggesting a role for infectious agents. The lymphomas did not express the mutant collagen XIII, indicating that its influence on tumorigenesis was B-cell extrinsic and likely to be associated with collagen XIII–positive tissues drained by the MLN. Studies of the small intestines of transgenic mice showed that the subepithelial basement membranes (BM) were highly abnormal and that they exhibited heightened expression of genes involved in immune responses. These results define collagen XIII–dependent maintenance of the intestinal BM as a previously unappreciated component of immune responses and a critical determinant of cancer susceptibility. [Cancer Res 2008;68(24):10324–31]
Data from The Relative Contribution of Point Mutations and Genomic Rearrangements in BRCA1 and BRCA2 in High-Risk Breast Cancer Families
Authors: Palma Maurizia Dalla , Domchek Susan M. , Stopfer Jill , Erlichman Julie , Siegfried Jill D. , Tigges-Cardwell Jessica , Mason Bernard A. , Rebbeck Timothy R. , Nathanson Katherine L.
Published: March 2024

Abstract
The demand for BRCA1 and BRCA2 mutation screening is increasing as their identification will affect medical management. However, both the contribution of different mutation types in BRCA1 and BRCA2 and whom should be offered testing for large genomic rearrangements have not been well established in the U.S. high-risk population. We define the prevalence and spectrum of point mutations and genomic rearrangements in BRCA genes in a large U.S. high-risk clinic population of both non-Ashkenazi and Ashkenazi Jewish descent, using a sample set representative of the U.S. genetic testing population. Two hundred fifty-one probands ascertained through the University of Pennsylvania high-risk clinic, all with commercial testing for BRCA1 and BRCA2, with an estimated prevalence of BRCA mutation ≥10% using the Myriad II model and a DNA sample available, were studied. Individuals without deleterious point mutations were screened for genomic rearrangements in BRCA1 and BRCA2. In the 136 non-Ashkenazi Jewish probands, 36 (26%) BRCA point mutations and 8 (6%) genomic rearrangements (7 in BRCA1 and 1 in BRCA2) were identified. Forty-seven of the 115 (40%) Ashkenazi Jewish probands had point mutations; no genomic rearrangements were identified in the group without mutations. In the non-Ashkenazi Jewish probands, genomic rearrangements constituted 18% of all identified BRCA mutations; estimated mutation prevalence (Myriad II model) was not predictive of their presence. Whereas these findings should be confirmed in larger sample sets, our data suggest that genomic rearrangement testing be considered in all non-Ashkenazi Jewish women with an estimated mutation prevalence ≥10%. [Cancer Res 2008;68(17):7006–14]
Data from Coordinated Regulation of Cell Cycle Transcripts by p53-Inducible microRNAs, miR-192 and miR-215
Authors: Georges Sara A. , Biery Matthew C. , Kim Soo-yeon , Schelter Janell M. , Guo Jane , Chang Aaron N. , Jackson Aimee L. , Carleton Michael O. , Linsley Peter S. , Cleary Michele A. , Chau B. Nelson
Published: March 2024

Abstract
Cell cycle arrest in response to DNA damage is an important antitumorigenic mechanism. MicroRNAs (miRNAs) were recently shown to play key regulatory roles in cell cycle progression. For example, miR-34a is induced in response to p53 activation and mediates G1 arrest by down-regulating multiple cell cycle–related transcripts. Here we show that genotoxic stress promotes the p53-dependent up-regulation of the homologous miRNAs miR-192 and miR-215. Like miR-34a, activation of miR-192/215 induces cell cycle arrest, suggesting that multiple miRNA families operate in the p53 network. Furthermore, we define a downstream gene expression signature for miR-192/215 expression, which includes a number of transcripts that regulate G1 and G2 checkpoints. Of these transcripts, 18 transcripts are direct targets of miR-192/215, and the observed cell cycle arrest likely results from a cooperative effect among the modulations of these genes by the miRNAs. Our results showing a role for miR-192/215 in cell proliferation combined with recent observations that these miRNAs are underexpressed in primary cancers support the idea that miR-192 and miR-215 function as tumor suppressors. [Cancer Res 2008;68(24):10105–12]
Data from Prevalence, Acquisition, and Clearance of Cervical Human Papillomavirus Infection among Women with Normal Cytology: Hawaii Human Papillomavirus Cohort Study
Authors: Goodman Marc T. , Shvetsov Yurii B. , McDuffie Katharine , Wilkens Lynne R. , Zhu Xuemei , Thompson Pamela J. , Ning Lily , Killeen Jeffrey , Kamemoto Lori , Hernandez Brenda Y.
Published: March 2024

Abstract
Few natural history studies of cervical human papillomavirus (HPV) incidence and duration have been conducted among older women, especially from multiethnic populations. Viral and nonviral determinants of HPV acquisition and clearance were examined among 972 sexually active women, ages 18 to 85 years, recruited from clinics on Oahu, Hawaii, and followed for a mean duration of 15 months (range, 2–56 months). Interviews and cervical cell specimens for cytology and HPV DNA detection by PCR, using the PGMY09/PGMY11 primer system, were obtained at baseline and at 4-month intervals. The prevalence of cervical HPV infection was 25.6% at study entry. A total of 476 incident genotype-specific infections were observed during the follow-up period. The incidence of high-risk (HR) HPV types (9.26 per 1,000 woman-months) was similar to low-risk (LR) HPV types (8.24 per 1,000 woman-months). The most commonly acquired HR-HPV types were HPV-52, HPV-16, and HPV-31; and their incidence was increased significantly with a coexisting cervical HPV infection. Cervical HPV acquisition decreased with age, income, and long-term use of oral contraceptives and increased with number of sexual partners, use of hormonal creams, alcohol drinking, and condom use by a sexual partner. Cohort participants cleared 265 of the 476 incident infections during follow-up. LR-HPV infections cleared more rapidly than did HR-HPV infections (median, 180 days versus 224 days). Clearance times were enhanced among older women and women with multiple infections. Our data suggest several viral and nonviral determinants of cervical HPV acquisition and clearance that might be used in cervical cancer prevention programs. [Cancer Res 2008;68(21):8813–24]
Data from Protein Kinase A Effects of an Expressed PRKAR1A Mutation Associated with Aggressive Tumors
Authors: Meoli Elise , Bossis Ioannis , Cazabat Laure , Mavrakis Manos , Horvath Anelia , Stergiopoulos Sotiris , Shiferaw Miriam L. , Fumey Glawdys , Perlemoine Karine , Muchow Michael , Robinson-White Audrey , Weinberg Frank , Nesterova Maria , Patronas Yianna , Groussin Lionel , Bertherat Jérôme , Stratakis Constantine A.
Published: March 2024

Abstract
Most PRKAR1A tumorigenic mutations lead to nonsense mRNA that is decayed; tumor formation has been associated with an increase in type II protein kinase A (PKA) subunits. The IVS6+1G>T PRKAR1A mutation leads to a protein lacking exon 6 sequences [R1αΔ184-236 (R1αΔ6)]. We compared in vitro R1αΔ6 with wild-type (wt) R1α. We assessed PKA activity and subunit expression, phosphorylation of target molecules, and properties of wt-R1α and mutant (mt) R1α; we observed by confocal microscopy R1α tagged with green fluorescent protein and its interactions with Cerulean-tagged catalytic subunit (Cα). Introduction of the R1αΔ6 led to aberrant cellular morphology and higher PKA activity but no increase in type II PKA subunits. There was diffuse, cytoplasmic localization of R1α protein in wt-R1α– and R1αΔ6-transfected cells but the former also exhibited discrete aggregates of R1α that bound Cα; these were absent in R1αΔ6-transfected cells and did not bind Cα at baseline or in response to cyclic AMP. Other changes induced by R1αΔ6 included decreased nuclear Cα. We conclude that R1αΔ6 leads to increased PKA activity through the mt-R1α decreased binding to Cα and does not involve changes in other PKA subunits, suggesting that a switch to type II PKA activity is not necessary for increased kinase activity or tumorigenesis. [Cancer Res 2008;68(9):3133–41]
Data from “Active” Cancer Immunotherapy by Anti-Met Antibody Gene Transfer
Authors: Vigna Elisa , Pacchiana Giovanni , Mazzone Massimiliano , Chiriaco Cristina , Fontani Lara , Basilico Cristina , Pennacchietti Selma , Comoglio Paolo M.
Published: March 2024

Abstract
Gene therapy provides a still poorly explored opportunity to treat cancer by “active” immunotherapy as it enables the transfer of genes encoding antibodies directed against specific oncogenic proteins. By a bidirectional lentiviral vector, we transferred the cDNA encoding the heavy and light chains of a monoclonal anti-Met antibody (DN-30) to epithelial cancer cells. In vitro, the transduced cells synthesized and secreted correctly assembled antibodies with the expected high affinity, inducing down-regulation of the Met receptor and strong inhibition of the invasive growth response. The inhibitory activity resulted (a) from the interference of the antibody with the Met receptor intracellular processing (“cell autonomous activity,” in cis) and (b) from the antibody-induced cleavage of Met expressed at the cell surface (“bystander effect,” in trans). The monoclonal antibody gene transferred into live animals by systemic administration or by local intratumor delivery resulted in substantial inhibition of tumor growth. These data provide proof of concept both for targeting the Met receptor and for a gene transfer–based immunotherapy strategy. [Cancer Res 2008;68(22):9176–83]
Data from Pericentromeric Instability and Spontaneous Emergence of Human Neoacrocentric and Minute Chromosomes in the Alternative Pathway of Telomere Lengthening
Authors: Gagos Sarantis , Chiourea Maria , Christodoulidou Agni , Apostolou Eftichia , Raftopoulou Christina , Deustch Samuel , Jefford Charles-Edward , Irminger-Finger Irmgard , Shay Jerry W. , Antonarakis Stylianos E.
Published: March 2024

Abstract
In the alternative pathway of telomere lengthening (ALT), neoplastic cell growth is prolonged by telomere recombination. We show that ALT is unexpectedly characterized by high rates of ongoing pericentromeric chromosomal instability. Combined with telomeric recombination, ALT pericentromeric instability generates neoacrocentric chromosomes. In the present studies, we describe a subgroup of ALT neoacrocentric minute chromosomes, composed of DNA entities two to five times smaller in size than human chromosome 21. The frequencies of ALT minute chromosomes were increased by γ-irradiation and suppressed by telomerase. Continuous growth after telomerase inhibition/depletion was followed by increased rates of telomeric sister chromatid recombination and the emergence of minute chromosomes. We show that ALT minute chromosomes were derived from true centromeric fissions and/or chromosomal breakage/fusion/bridge cycles. They exhibit a two-chromatid structure, carry genomic DNA, centromeric and telomeric repeats, and display regular mitotic functionality. These observations are important in understanding the global genomic instability that characterizes most human advanced malignancies. [Cancer Res 2008;68(19):8146–55]
Data from Hypoxia-Inducible Carbonic Anhydrase IX and XII Promote Tumor Cell Growth by Counteracting Acidosis through the Regulation of the Intracellular pH
Authors: Chiche Johanna , Ilc Karine , Laferrière Julie , Trottier Eric , Dayan Frédéric , Mazure Nathalie M. , Brahimi-Horn M. Christiane , Pouysségur Jacques
Published: March 2024

Abstract
Acidosis of the tumor microenvironment is typical of a malignant phenotype, particularly in hypoxic tumors. All cells express multiple isoforms of carbonic anhydrase (CA), enzymes catalyzing the reversible hydration of carbon dioxide into bicarbonate and protons. Tumor cells express membrane-bound CAIX and CAXII that are controlled via the hypoxia-inducible factor (HIF). Despite the recognition that tumor expression of HIF-1α and CAIX correlates with poor patient survival, the role of CAIX and CAXII in tumor growth is not fully resolved. To understand the advantage that tumor cells derive from expression of both CAIX and CAXII, we set up experiments to either force or invalidate the expression of these enzymes. In hypoxic LS174Tr tumor cells expressing either one or both CA isoforms, we show that (a) in response to a “CO2 load,” both CAs contribute to extracellular acidification and (b) both contribute to maintain a more alkaline resting intracellular pH (pHi), an action that preserves ATP levels and cell survival in a range of acidic outside pH (6.0–6.8) and low bicarbonate medium. In vivo experiments show that ca9 silencing alone leads to a 40% reduction in xenograft tumor volume with up-regulation of ca12 mRNA levels, whereas invalidation of both CAIX and CAXII gives an impressive 85% reduction. Thus, hypoxia-induced CAIX and CAXII are major tumor prosurvival pHi-regulating enzymes, and their combined targeting shows that they hold potential as anticancer targets. [Cancer Res 2009;69(1):358–68]
Data from Identification of p18INK4c as a Tumor Suppressor Gene in Glioblastoma Multiforme
Authors: Solomon David A. , Kim Jung-Sik , Jenkins Sultan , Ressom Habtom , Huang Michael , Coppa Nicholas , Mabanta Lauren , Bigner Darell , Yan Hai , Jean Walter , Waldman Todd
Published: March 2024

Abstract
Genomic alterations leading to aberrant activation of cyclin/cyclin-dependent kinase (cdk) complexes drive the pathogenesis of many common human tumor types. In the case of glioblastoma multiforme (GBM), these alterations are most commonly due to homozygous deletion of p16INK4a and less commonly due to genomic amplifications of individual genes encoding cyclins or cdks. Here, we describe deletion of the p18INK4c cdk inhibitor as a novel genetic alteration driving the pathogenesis of GBM. Deletions of p18INK4c often occurred in tumors also harboring homozygous deletions of p16INK4a. Expression of p18INK4c was completely absent in 43% of GBM primary tumors studied by immunohistochemistry. Lentiviral reconstitution of p18INK4c expression at physiologic levels in p18INK4c-deficient but not p18INK4c-proficient GBM cells led to senescence-like G1 cell cycle arrest. These studies identify p18INK4c as a GBM tumor suppressor gene, revealing an additional mechanism leading to aberrant activation of cyclin/cdk complexes in this terrible malignancy. [Cancer Res 2008;68(8):2564–9]
Data from Molecular Basis for the Critical Role of Suppressor of Cytokine Signaling-1 in Melanoma Brain Metastasis
Authors: Huang Feng-Ju , Steeg Patricia S. , Price Janet E. , Chiu Wen-Tai , Chou Ping-Chieh , Xie Keping , Sawaya Raymond , Huang Suyun
Published: March 2024

Abstract
Our recent study found that activation of signal transducer and activator of transcription 3 (Stat3) is up-regulated in human brain metastatic cells and contributes to brain metastasis of melanoma. However, the molecular mechanisms underlying this increased Stat3 activation and effect on brain metastasis are unknown. In this report, we showed that the expression of Janus-activated kinase 2 (JAK2), a Stat3 activator, was increased, whereas the expression of a negative regulator of Stat3, suppressor of cytokine signaling-1 (SOCS-1), was reduced in the brain metastatic melanoma cell line A375Br, relative to that in the parental A375P cell line. Consistently, SOCS-1 expression was also lower in the human brain metastatic tissues than in the primary melanoma tissues. Mechanistically, increased JAK2 expression in the A375Br cells was due to, at least in part, its decreased degradation, which was directly correlated with low expression of SOCS-1. Moreover, restoration of SOCS-1 expression resulted in the inhibition of Stat3 activation, whereas depletion of SOCS-1 up-regulated Stat3 activation. These clinical, experimental, and mechanistic findings strongly suggest that increased activation of Stat3 in brain metastatic melanoma cells might be due to decreased SOCS-1 expression. Furthermore, restoration of SOCS-1 expression in brain metastatic A375Br cells significantly inhibited brain metastasis in animal models (P < 0.001). Additionally, alterations of SOCS-1 expression profoundly affected the expression of matrix metalloproteinase-2 (MMP-2), basic fibroblast growth factor (bFGF), and vascular endothelial growth factor (VEGF) and the melanoma cell invasion and angiogenesis. Collectively, these data suggest that the loss of SOCS-1 expression is a critical event, leading to elevated Stat3 signaling and overexpression of MMP-2, bFGF, and VEGF, as well as enhanced invasion and angiogenesis of melanoma cells, consequently promoting brain metastasis. [Cancer Res 2008;68(23):9634–42]
Data from Common Familial Colorectal Cancer Linked to Chromosome 7q31: A Genome-Wide Analysis
Authors: Neklason Deborah W. , Kerber Richard A. , Nilson David B. , Anton-Culver Hoda , Schwartz Ann G. , Griffin Constance A. , Lowery Jan T. , Schildkraut Joellen M. , Evans James P. , Tomlinson Gail E. , Strong Louise C. , Miller Alexander R. , Stopfer Jill E. , Finkelstein Dianne M. , Nadkarni Prakash M. , Kasten Carol H. , Mineau Geraldine P. , Burt Randall W.
Published: March 2024

Abstract
Present investigations suggest that ∼30% of colorectal cancer cases arise on the basis of inherited factors. We hypothesize that the majority of inherited factors are moderately penetrant genes, common in the population. We use an affected sibling pair approach to identify genetic regions that are coinherited by siblings with colorectal cancer. Individuals from families with at least two siblings diagnosed with colorectal adenocarcinoma or high-grade dysplasia were enrolled. Known familial colorectal cancer syndromes were excluded. A genome-wide scan on 151 DNA samples from 70 kindreds was completed using deCODE 1100 short tandem repeat marker set at an average 4-cM density. Fine mapping on a total of 184 DNAs from 83 kindreds was done in regions suggesting linkage. Linkage analysis was accomplished with Merlin analysis package. Nonparametric linkage analysis revealed three genetic regions with logarithm of the odds (LOD) scores ≥2.0: Ch. 3q29, LOD 2.61 (P = 0.0003); Ch. 4q31.3, LOD 2.13 (P = 0.0009); and Ch. 7q31.31, LOD 3.08 (P = 0.00008). Affected siblings with increased sharing at the 7q31 locus have a 3.8-year (± 3.5) earlier age of colorectal cancer onset although this is not statistically significant (P = 0.11). No significant linkage was found near genes causing known syndromes or regions previously reported (8q24, 9q22, and 11q23). The chromosome 3q21–q24 region reported to be linked in colorectal cancer relative pairs is supported by our study, albeit a minor peak (LOD 0.9; P = 0.02). No known familial cancer genes reside in the 7q31 locus, and thus the identified region may contain a novel susceptibility gene responsible for common familial colorectal cancer. [Cancer Res 2008;68(21):8993–7]
Data from LRRC3B, Encoding a Leucine-Rich Repeat-Containing Protein, Is a Putative Tumor Suppressor Gene in Gastric Cancer
Authors: Kim Mirang , Kim Jeong-Hwan , Jang Hay-Ran , Kim Hwan-Mook , Lee Chang-Woo , Noh Seung-Moo , Song Kyu-Sang , Cho June-Sik , Jeong Hyun-Yong , Hahn Yoonsoo , Yeom Young-Il , Yoo Hyang-Sook , Kim Yong Sung
Published: March 2024

Abstract
Leucine-rich repeat-containing 3B (LRRC3B) is an evolutionarily highly conserved leucine-rich repeat-containing protein, but its biological significance is unknown. Using restriction landmark genomic scanning and pyrosequencing, we found that the promoter region of LRRC3B was aberrantly methylated in gastric cancer. Gastric cancer cell lines displayed epigenetic silencing of LRRC3B, but treatment with the DNA methylation inhibitor 5-aza-2′-deoxycytidine and/or the histone deacetylase inhibitor trichostatin A increased LRRC3B expression in gastric cancer cell lines. Real-time reverse transcription-PCR analysis of 96 paired primary gastric tumors and normal adjacent tissues showed that LRRC3B expression was reduced in 88.5% of gastric tumors compared with normal adjacent tissues. Pyrosequencing analysis of the promoter region revealed that LRRC3B was significantly hypermethylated in gastric tumors. Stable transfection of LRRC3B in SNU-601 cells, a gastric cancer cell line, inhibited anchorage-dependent and anchorage-independent colony formation, and LRRC3B expression suppressed tumorigenesis in nude mice. Microarray analysis of LRRC3B-expressing xenograft tumors showed induction of immune response–related genes and IFN signaling genes. H&E-stained sections of LRRC3B-expressing xenograft tumors showed lymphocyte infiltration in the region. We suggest that LRRC3B is a putative tumor suppressor gene that is silenced in gastric cancers by epigenetic mechanisms and that LRRC3B silencing in cancer may play an important role in tumor escape from immune surveillance. [Cancer Res 2008;68(17):7147–55]
Data from The Chemokine Receptor CX3CR1 Is Involved in the Neural Tropism and Malignant Behavior of Pancreatic Ductal Adenocarcinoma
Authors: Marchesi Federica , Piemonti Lorenzo , Fedele Giuseppe , Destro Annarita , Roncalli Massimo , Albarello Luca , Doglioni Claudio , Anselmo Achille , Doni Andrea , Bianchi Paolo , Laghi Luigi , Malesci Alberto , Cervo Luigi , Malosio MariaLuisa , Reni Michele , Zerbi Alessandro , Di Carlo Valerio , Mantovani Alberto , Allavena Paola
Published: March 2024

Abstract
Tumor perineural dissemination is a hallmark of human pancreatic ductal adenocarcinoma (PDAC) and represents a major source of local tumor recurrence after surgery. In this study, we provide in vitro and in vivo evidence that the chemokine receptor CX3CR1 may be involved in the neurotropism of PDAC cells to local peripheral nerves. Neoplastic cells from PDAC cell lines and surgical specimens express the chemokine receptor CX3CR1, absent in normal pancreatic ducts. Its unique ligand, the transmembrane chemokine CX3CL1, is expressed by neurons and nerve fibers. CX3CR1 + PDAC cell lines migrated in response to human recombinant CX3CL1 and specifically adhered to CX3CL1-expressing cells of neural origin via mechanisms involving activation of G proteins, β1 integrins, and focal adhesion kinase. In vivo experiments with transplanted PDAC showed that only CX3CR1-transfected tumor cells infiltrated the local peripheral nerves. Immunohistochemistry of CX3CR1 in PDAC specimens revealed that 90% of the samples were positive with a heterogeneous pattern of expression. High receptor score was significantly associated with more prominent tumor perineural infiltration evaluated histologically (P = 0.026). Regression analyses (univariate and multivariate) showed that high CX3CR1 expression and perineural invasion were strongly associated with local and earlier tumor recurrence (P = 0.007). Collectively, this study shows that the CX3CR1 receptor may be involved in PDAC tumor neurotropism and is a relevant and independent risk factor to predict an early local tumor relapse in resected patients. Thus, the CX3CR1-CX3CL1 axis could represent a valuable therapeutic target to prevent tumor perineural dissemination in pancreatic cancer. [Cancer Res 2008;68(21):9060–9]
Data from Increased c-Jun-NH2-Kinase Signaling in Neurofibromatosis-1 Heterozygous Microglia Drives Microglia Activation and Promotes Optic Glioma Proliferation
Authors: Daginakatte Girish C. , Gianino Scott M. , Zhao Nina W. , Parsadanian Alexander S. , Gutmann David H.
Published: March 2024

Abstract
Neurofibromatosis-1 (NF1) is a common tumor predisposition syndrome in which affected individuals develop benign and malignant tumors. Previous studies from our laboratory and others have shown that benign tumor formation in Nf1 genetically engineered mice (GEM) requires a permissive tumor microenvironment. In the central nervous system, Nf1 loss in glia is insufficient for glioma formation unless coupled with Nf1 heterozygosity in the brain. Our subsequent studies identified Nf1+/− microglia as a critical cellular determinant of optic glioma growth in Nf1 GEM. Using NF1 as an experimental paradigm to further characterize the role of microglia in glioma growth, we first examined the properties of Nf1+/− microglia in vitro and in vivo. Nf1+/− microglia exhibit increased proliferation and motility and express elevated levels of genes associated with microglia activation. We further show that Nf1+/− microglia harbor high levels of activated c-Jun-NH2-kinase (JNK) without any significant changes in Akt, mitogen-activated protein kinase (MAPK), or p38-MAPK activity. In contrast, Nf1−/− astrocytes do not exhibit increased JNK activation. SP600125 inhibition of JNK activity in Nf1+/− microglia results in amelioration of the increased proliferation and motility phenotypes and reduces the levels of expression of activated microglia-associated transcripts. Moreover, SP600125 treatment of Nf1 optic glioma–bearing GEM results in reduced optic glioma proliferation in vivo. Collectively, these findings suggest that Nf1+/− microglia represent a good model system to study the role of specialized microglia in brain tumorigenesis and identify a unique Nf1 deregulated pathway for therapeutic studies aimed at abrogating microenvironmental signals that promote brain tumor growth. [Cancer Res 2008;68(24):10358–66]
Data from CYR61 and αVβ5 Integrin Cooperate to Promote Invasion and Metastasis of Tumors Growing in Preirradiated Stroma
Authors: Monnier Yan , Farmer Pierre , Bieler Gregory , Imaizumi Natsuko , Sengstag Thierry , Alghisi Gian Carlo , Stehle Jean-Christophe , Ciarloni Laura , Andrejevic-Blant Snezana , Moeckli Raphael , Mirimanoff René-Olivier , Goodman Simon L. , Delorenzi Mauro , Rüegg Curzio
Published: March 2024

Abstract
Radiotherapy is widely used to treat human cancer. Patients locally recurring after radiotherapy, however, have increased risk of metastatic progression and poor prognosis. The clinical management of postradiation recurrences remains an unresolved issue. Tumors growing in preirradiated tissues have an increased fraction of hypoxic cells and are more metastatic, a condition known as tumor bed effect. The transcription factor hypoxia inducible factor (HIF)-1 promotes invasion and metastasis of hypoxic tumors, but its role in the tumor bed effect has not been reported. Here, we show that tumor cells derived from SCCVII and HCT116 tumors growing in a preirradiated bed, or selected in vitro through repeated cycles of severe hypoxia, retain invasive and metastatic capacities when returned to normoxia. HIF activity, although facilitating metastatic spreading of tumors growing in a preirradiated bed, is not essential. Through gene expression profiling and gain- and loss-of-function experiments, we identified the matricellular protein CYR61 and αVβ5 integrin as proteins cooperating to mediate these effects. The anti-αV integrin monoclonal antibody 17E6 and the small molecular αVβ3/αVβ5 integrin inhibitor EMD121974 suppressed invasion and metastasis induced by CYR61 and attenuated metastasis of tumors growing within a preirradiated field. These results represent a conceptual advance to the understanding of the tumor bed effect and identify CYR61 and αVβ5 integrin as proteins that cooperate to mediate metastasis. They also identify αV integrin inhibition as a potential therapeutic approach for preventing metastasis in patients at risk for postradiation recurrences. [Cancer Res 2008;68(18):7323–31]
Data from FoxM1B Transcriptionally Regulates Vascular Endothelial Growth Factor Expression and Promotes the Angiogenesis and Growth of Glioma Cells
Authors: Zhang Yujian , Zhang Nu , Dai Bingbing , Liu Mingguang , Sawaya Raymond , Xie Keping , Huang Suyun
Published: March 2024

Abstract
We previously found that FoxM1B is overexpressed in human glioblastomas and that forced FoxM1B expression in anaplastic astrocytoma cells leads to the formation of highly angiogenic glioblastoma in nude mice. However, the molecular mechanisms by which FoxM1B enhances glioma angiogenesis are currently unknown. In this study, we found that vascular endothelial growth factor (VEGF) is a direct transcriptional target of FoxM1B. FoxM1B overexpression increased VEGF expression, whereas blockade of FoxM1 expression suppressed VEGF expression in glioma cells. Transfection of FoxM1 into glioma cells directly activated the VEGF promoter, and inhibition of FoxM1 expression by FoxM1 siRNA suppressed VEGF promoter activation. We identified two FoxM1-binding sites in the VEGF promoter that specifically bound to the FoxM1 protein. Mutation of these FoxM1-binding sites significantly attenuated VEGF promoter activity. Furthermore, FoxM1 overexpression increased and inhibition of FoxM1 expression suppressed the angiogenic ability of glioma cells. Finally, an immunohistochemical analysis of 59 human glioblastoma specimens also showed a significant correlation between FoxM1 overexpression and elevated VEGF expression. Our findings provide both clinical and mechanistic evidence that FoxM1 contributes to glioma progression by enhancing VEGF gene transcription and thus tumor angiogenesis. [Cancer Res 2008;68(21):8733–42]