bluuebunny/crossref_metadata_2025_split huggingface dataset:
Nitric Oxide, a Mediator of Inflammation, Suppresses Tumorigenesis
Authors: Hussain S. Perwez , Trivers Glennwood E. , Hofseth Lorne J. , He Peijun , Shaikh Irfan , Mechanic Leah E. , Doja Saira , Jiang Weidong , Subleski Jeffrey , Shorts Lynnette , Haines Diana , Laubach Victor E. , Wiltrout Robert H. , Djurickovic Draginja , Harris Curtis C. 
Published: September 2005

AbstractInflammation influences the development of cancer. The nitric oxide synthase (NOS2) is induced by inflammatory cytokines, e.g., tumor necrosis factor α and interleukin 1β, and produces nitric oxide (NO·), a critical mediator of the inflammatory response. Because p53 governs NO· production by transcriptionally transrepressing NOS2, we used a genetic strategy to determine whether NO· and p53 cooperatively regulate tumorigenesis. Lymphomas developed more rapidly in p53−/−NOS2−/− or p53−/−NOS2+/− mice than in p53−/−NOS2+/+ mice that were cross-bred into a &gt;95% C57BL6 background and maintained in a pathogen-free condition. Likewise, sarcomas and lymphomas developed faster in p53+/−NOS2−/− or p53+/−NOS2+/− than in p53+/−NOS2+/+ mice. When compared with the double knockout mice, p53−/−NOS2+/+ mice showed a higher apoptotic index and a decreased proliferation index with an increased expression of death receptor ligands, CD95-L and tumor necrosis factor-related apoptosis-inducing ligand, and the cell cycle checkpoint protein, p21waf1, in the spleen and thymus before tumor development. Furthermore, mice deficient in both p53 and NOS2 produced a high level of anti-inflammatory interleukin 10 when compared with p53-deficient mice. These studies provide genetic and mechanistic evidence that NO· can suppress tumorigenesis.
Nitric Oxide and Ionizing Radiation Synergistically Promote Apoptosis and Growth Inhibition of Cancer by Activating p53
Authors: Cook Tracy , Wang Zifa , Alber Sean , Liu Kaihong , Watkins Simon C. , Vodovotz Yoram , Billiar Timothy R. , Blumberg David 
Published: September 2005

Abstract
Nitric oxide (NO) is a potent tumor radiosensitizer; however, its clinical use is limited by systemic side effects. We have demonstrated previously that gene transfer of the human inducible NO synthase (iNOS) gene into tumor cells and tumors induces high-output NO production that significantly enhances tumor radioresponsiveness, with no observed side effects. Notably, iNOS gene transfer enhances tumor radioresponsiveness via apoptotic cell death. Because NO and ionizing radiation are both known to promote p53-dependent apoptosis, we hypothesized that p53 activation might be a primary mechanism for the synergy of these two genotoxic stresses. We report that NO and ionizing radiation synergistically activate p53 in colorectal cancers grown in athymic mice by augmenting phosphorylation of p53 at serine 15. The effect of NO and ionizing radiation on tumor cell apoptosis and tumor radioresponsiveness is significantly reduced in p53 knockout isogenic cancer cell lines. Furthermore, the transfer of both p53 and iNOS genes into tumor cells lacking functional p53 enhanced their radioresponsiveness more than transfer of either gene alone.
Functional Analysis of the Contribution of RhoA and RhoC GTPases to Invasive Breast Carcinoma
Authors: Simpson Kaylene J. , Dugan Aisling S. , Mercurio Arthur M. 
Published: September 2005

Abstract
Although the RhoA and RhoC proteins comprise an important subset of the Rho GTPase family that have been implicated in invasive breast carcinomas, attributing specific functions to these individual members has been difficult. We have used a stable retroviral RNA interference approach to generate invasive breast carcinoma cells (SUM-159 cells) that lack either RhoA or RhoC expression. Analysis of these cells enabled us to deduce that RhoA impedes and RhoC stimulates invasion. Unexpectedly, this analysis also revealed a compensatory relationship between RhoA and RhoC at the level of both their expression and activation, and a reciprocal relationship between RhoA and Rac1 activation.
Bone Morphogenetic Protein (BMP)-6 Signaling and BMP Antagonist Noggin in Prostate Cancer
Authors: Haudenschild Dominik R. , Palmer Sabrina M. , Moseley Timothy A. , You Zongbing , Reddi A. Hari 
Published: September 2005

Abstract
It has been proposed that the osteoblastic nature of prostate cancer skeletal metastases is due in part to elevated activity of bone morphogenetic proteins (BMPs). BMPs are osteoinductive morphogens, and elevated expression of BMP-6 correlates with skeletal metastases of prostate cancer. In this study, we investigated the expression levels of BMPs and their modulators in prostate, using microarray analysis of cell cultures and gene expression. Addition of exogenous BMP-6 to DU-145 prostate cancer cell cultures inhibited their growth by up-regulation of several cyclin-dependent kinase inhibitors such as p21/CIP, p18, and p19. Expression of noggin, a BMP antagonist, was significantly up-regulated by BMP-6 by microarray analysis and was confirmed by quantitative reverse transcription-polymerase chain reaction and at the protein level. Noggin protein was present in prostate biopsies and localized to the epithelial components of prostate by immunohistochemistry. Recombinant noggin inhibited the function of BMP-6, suggesting a negative feedback regulation of BMP activity and indicating a strategy for the development of a novel therapeutic target in the treatment of painful osteosclerotic bone metastases of prostate cancer.
Immunological Prevention of a Multigene Cancer Syndrome
Authors: Croci Stefania , Nicoletti Giordano , Landuzzi Lorena , De Giovanni Carla , Astolfi Annalisa , Marini Chiara , Di Carlo Emma , Musiani Piero , Forni Guido , Nanni Patrizia , Lollini Pier-Luigi 
Published: September 2005

Abstract
Vaccines effectively prevent the onset of tumors in transgenic mice carrying activated oncogenes; however, human tumors are caused by combined alterations in oncogenes and oncosuppressor genes. We evaluated the impact of prophylactic vaccines in HER-2/neu transgenic, p53 wild-type/null mice that succumb to an aggressive cancer syndrome comprising mammary and salivary gland carcinomas and rhabdomyosarcoma. A vaccine made of allogeneic mammary carcinoma cells expressing HER-2/neu and interleukin 12 afforded long-term protection from tumor onset. Tumor prevention was mediated by T cell–derived cytokines, in particular γ-interferon, and by anti–HER-2/neu antibodies. HER-2/neu expression was inhibited in target tissues of vaccinated mice, and somatic loss of the wild-type p53 allele did not occur. A highly effective vaccine against a single oncoprotein induced a powerful immune response that arrested multistep carcinogenesis in distinct target tissues.
Head and Neck Cancer
Authors: Grandis Jennifer R. , Pietenpol Jennifer A. , Greenberger Joel S. , Pelroy Richard A. , Mohla Suresh 
Published: September 2005

Abstract
Head and neck squamous cell carcinoma (HNSCC) is the most common malignant neoplasm arising in the mucosa of the upper aerodigestive tract. Nearly two thirds of patients present with advanced (stage III and IV) disease. Fifty percent of HNSCC patients die of their disease, and 5% of HNSCC patients per year will develop additional second primary tumors. Currently used therapeutic modalities (surgery, radiation, and/or chemotherapy) have been associated with rather modest improvements in patient survival. The Head and Neck Cancer: Research and Therapeutic Opportunities Workshop (held in Washington, DC, May 24–26, 2004) was organized by the Division of Cancer Biology at the National Cancer Institute to identify research areas and directions that will advance understanding of HNSCC biology and accelerate clinical translation. The primary goal of the workshop was to identify the barriers that impede basic science discovery and the translation of these developments to the clinical setting. Over a 2.5-day period, experts in both HNSCC and other cancer-related fields met to identify and prioritize the key areas for future research. The overall consensus was that HNSCC is a relatively understudied malignancy and that investigations that focus on the biology of this tumor have the potential to impact significantly on the prevention and treatment of epithelial malignancies. The chief objective is to communicate these research goals to the cancer biology community and encourage more interest in HNSCC as a tumor model to test translational research hypotheses.
Increased Insulin-Like Growth Factor I Receptor Expression and Signaling Are Components of Androgen-Independent Progression in a Lineage-Derived Prostate Cancer Progression Model
Authors: Krueckl Sandra L. , Sikes Robert A. , Edlund N. Magnus , Bell Robert H. , Hurtado-Coll Antonio , Fazli Ladan , Gleave Martin E. , Cox Michael E. 
Published: September 2005

Abstract
Apoptosis and inhibition of mitosis are primary mechanisms mediating androgen ablation therapy-induced regression of prostate cancer (PCa). However, PCa readily becomes androgen independent, leading to fatal disease. Up-regulated growth and survival signaling is implicated in development of resistance to androgen ablation therapy. We are testing the hypothesis that insulin-like growth factor (IGF) responsiveness is required for androgen-independent (AI) progression. Using the LNCaP human PCa progression model, we have determined that IGF-I–mediated protection from apoptotic stress and enhanced mitotic activity is androgen dependent in LNCaP cells but is androgen independent in lineage-derived C4-2 cells. Both cell lines exhibit androgen-responsive patterns of IGF-I receptor (IGF-IR) expression, activation, and signaling to insulin receptor substrate-2 and AKT. However, C4-2 cells express higher levels of IGF-IR mRNA and protein and exhibit enhanced IGF-I–mediated phosphorylation and downstream signaling under androgen-deprived conditions. In comparisons of naïve and AI metastatic human PCa specimens, we have confirmed that IGF-IR levels are elevated in advanced disease. Together with our LNCaP/C4-2 AI progression model data, these results indicate that increased IGF-IR expression is associated with AI antiapoptotic and promitotic IGF signaling in PCa disease progression.
Spontaneous Regression of Grade 3 Vulvar Intraepithelial Neoplasia Associated with Human Papillomavirus-16–Specific CD4+ and CD8+ T-Cell Responses
Authors: Villada Isabelle Bourgault , Barracco Micheline Moyal , Ziol Marianne , Chaboissier Aude , Barget Nathalie , Berville Sophie , Paniel Bernard , Jullian Eric , Clerici Thierry , Maillère Bernard , Guillet Jean Gérard 
Published: September 2005

AbstractCell-mediated immunity directed against human papillomavirus 16 (HPV-16) antigens was studied in six patients affected with grade 3 vulvar intraepithelial neoplasia (VIN3, also known as bowenoid papulosis). Five of the patients presented with a chronic and persistent disease that relapsed after destructive treatments. They showed no detectable anti-HPV blood T-cell responses and no T-cell intraepidermal vulvar infiltrate containing both CD4+ and CD8+ lymphocytes. The last patient had a complete clearance of viral lesions, 8 months after disease onset and 2 months after electrocoagulation of &lt;50% of the VIN3 lesions. She showed high frequency anti-E6 and anti-E7 effector blood T cells by ex vivo ELISpot-IFNγ assay before clinical regression. Immunohistochemical study of her vulvar biopsy revealed a marked dermal infiltrate containing a majority of CD4+ T lymphocytes and an epidermal infiltrate made up of both CD4+ and CD8+ T cells. This seems to be the first evidence of an association between spontaneous regression of VIN3 lesions and HPV-specific T-cell responses detectable in the blood. Hence, an increase of HPV-specific effector T lymphocyte responses by vaccine-based therapeutic strategies might be useful to clear the lesions in bowenoid papulosis disease.
Survivin Deregulation in β-Tubulin Mutant Ovarian Cancer Cells Underlies Their Compromised Mitotic Response to Taxol
Authors: Zhou Jun , O’Brate Aurora , Zelnak Amelia , Giannakakou Paraskevi 
Published: September 2005

Abstract
Taxol is one of the most successful drugs for the treatment of cancer because of its ability to target tubulin, block cell cycle progression at mitosis, and induce apoptosis. Despite the success of Taxol, the development of drug resistance hampers its clinical applicability. Herein we report that β-tubulin mutant, Taxol-resistant ovarian cancer cells exhibit defective mitotic response to Taxol, even at high concentrations that are sufficient to trigger apoptosis. This mitotic response-defective phenotype is independent of p53 status. We have found that survivin, the mitosis regulator and inhibitor of apoptosis protein, is deregulated in these Taxol-resistant cancer cells; Taxol fails to induce survivin levels and survivin phosphorylation in these cells, in contrast to their parental drug-sensitive counterparts. Exogenous expression of wild-type survivin is able to restore the mitotic response of the resistant cells to Taxol treatment. On the other hand, exogenous expression of dominant-negative survivin abrogates the Taxol-induced mitotic response in drug-sensitive cancer cells. We have also found that overexpression of the mitotic kinase Cdk1, which phosphorylates survivin, is unable to restore the Taxol-induced mitotic response in the resistant cells. Our results show the importance of survivin for the mitotic response in the context of Taxol resistance and provide novel insights into the mechanisms of mitotic arrest and apoptosis induced by microtubule-targeting agents.
Nanoparticle-Aptamer Bioconjugates
Authors: Farokhzad Omid C. , Jon Sangyong , Khademhosseini Ali , Tran Thanh-Nga T. , LaVan David A. , Langer Robert 
Published: September 2005

Abstract
Nucleic acid ligands (aptamers) are potentially well suited for the therapeutic targeting of drug encapsulated controlled release polymer particles in a cell- or tissue-specific manner. We synthesized a bioconjugate composed of controlled release polymer nanoparticles and aptamers and examined its efficacy for targeted delivery to prostate cancer cells. Specifically, we synthesized poly(lactic acid)-block-polyethylene glycol (PEG) copolymer with a terminal carboxylic acid functional group (PLA-PEG-COOH), and encapsulated rhodamine-labeled dextran (as a model drug) within PLA-PEG-COOH nanoparticles. These nanoparticles have the following desirable characteristics: (a) negative surface charge (−50 ± 3 mV, mean ± SD, n = 3), which may minimize nonspecific interaction with the negatively charged nucleic acid aptamers; (b) carboxylic acid groups on the particle surface for potential modification and covalent conjugation to amine-modified aptamers; and (c) presence of PEG on particle surface, which enhances circulating half-life while contributing to decreased uptake in nontargeted cells. Next, we generated nanoparticle-aptamer bioconjugates with RNA aptamers that bind to the prostate-specific membrane antigen, a well-known prostate cancer tumor marker that is overexpressed on prostate acinar epithelial cells. We demonstrated that these bioconjugates can efficiently target and get taken up by the prostate LNCaP epithelial cells, which express the prostate-specific membrane antigen protein (77-fold increase in binding versus control, n = 150 cells per group). In contrast to LNCaP cells, the uptake of these particles is not enhanced in cells that do not express the prostate-specific membrane antigen protein. To our knowledge, this represents the first report of targeted drug delivery with nanoparticle-aptamer bioconjugates.
Loss of Heterozygosity of Chromosome 3p21 Is Associated with Mutant
TP53
and Better Patient Survival in Non–Small-Cell Lung Cancer
Authors: Marsit Carmen J. , Hasegawa Masayuki , Hirao Tomoko , Kim Duk-Hwan , Aldape Kenneth , Hinds Philip W. , Wiencke John K. , Nelson Heather H. , Kelsey Karl T. 
Published: September 2005

Abstract
Allelic loss of chromosome region 3p21.3 occurs early and frequently in non–small-cell lung cancer, and numerous tumor suppressor genes at this locus may be targets of inactivation. Using an incident case series study of non–small-cell lung cancer, we sought to determine the prevalence of loss of heterozygosity (LOH) in the 3p21.3 region and to examine the associations between this alteration and patient outcome, exposure to tobacco smoke, occupational asbestos exposure, and additional molecular alterations in these tumors. We examined LOH at 7 microsatellite markers in the chromosome 3p21.3 region, and LOH was present in at least one of the loci examined in 60% (156 of 258) of the tumors, with the prevalence of LOH at individual loci ranging from 15 to 56%. Occupational asbestos exposure and TP53 mutation were significantly associated with more extensive 3p21 LOH. In squamous cell carcinomas, measures of cumulative smoking dose were significantly lower in patients with LOH at 3p21, particularly in TP53 mutant tumors. Examining patient outcome, we found that in squamous cell carcinomas, having any LOH in this region was associated with a better overall survival (log-rank test, P &lt; 0.04). Together, these results indicate that allelic loss at 3p21 can affect patient outcome, and that this loss may initially be related to carcinogen exposure, but that extension of this loss is related to TP53 mutation status and occupational asbestos exposure.
The Prosurvival Activity of p53 Protects Cells from UV-Induced Apoptosis by Inhibiting c-Jun NH2-terminal Kinase Activity and Mitochondrial Death Signaling
Authors: Lo Pang-Kuo , Huang Sheng-Zhu , Chen Hsiang-Chin , Wang Fung-Fang 
Published: September 2005

Abstract
The cytoprotective function of p53 recently has been exploited as a therapeutic advantage for cancer prevention; agents activating the prosurvival activity of p53 are shown to prevent UV-induced damages. To explore the mechanisms of p53-mediated protection from UV-induced apoptosis, we have established stable clones of H1299 lung carcinoma cells expressing a temperature-sensitive p53 mutant, tsp53V143A. At the permissive temperature of 32°C, the tsp53V143A-expressing cells were arrested in G1 phase without the occurrence of apoptosis; consistent with this is the preferential induction of genes related to growth arrest and DNA damage repair. Previous expression of functional tsp53V143A for ≥18 hours inhibited the release of proapoptotic molecules from mitochondria and protected the cells from UV-induced apoptosis; moreover, it suppressed the activation of c-Jun NH2-terminal kinase (JNK) signaling and relieved the effect of UV on p53 target gene activation. p53 associated with JNK and inhibited its kinase activity. Using the p53-null H1299 cells, we showed that inhibition of JNK blocked the UV-elicited mitochondrial death signaling and caspase activation. Our results suggest that the ability of p53 to bind and inactivate JNK, together with the activation of the p53 target genes related to cell cycle arrest and DNA damage repair, is responsible for its protection of cells against UV-induced apoptosis.
COP1, the Negative Regulator of p53, Is Overexpressed in Breast and Ovarian Adenocarcinomas
Authors: Dornan David , Bheddah Sheila , Newton Kim , Ince William , Frantz Gretchen D. , Dowd Patrick , Koeppen Hartmut , Dixit Vishva M. , French Dorothy M. 
Published: September 2005

Abstract
The tumor suppressor protein p53 plays a central role in protecting normal cells from undergoing transformation. Thus, it is fitting that cancer cells selectively dampen the p53 response to gain a selective growth advantage. In fact, the p53 gene is the most commonly mutated tumor suppressor gene in human cancers, and if the gene is not mutated, then other components of the p53 pathways are skewed to dampen the p53 response to stress. We recently identified COP1 as a novel and critical negative regulator of p53. COP1 is a RING finger-containing protein that targets p53 for degradation to the proteasome and is necessary for p53 turnover in normal and cancer cells. However, the association between COP1 and cancer remains to be determined. We performed expression analysis of COP1 in ovarian and breast cancer tissue microarrays. COP1 is significantly overexpressed in 81% (25 of 32) of breast and 44% (76 of 171) of ovarian adenocarcinoma as assessed by in situ hybridization and immunohistochemistry. Overexpression of COP1 correlated with a striking decrease in steady state p53 protein levels and attenuation of the downstream target gene, p21, in cancers that retain a wild-type p53 gene status. Overall, these results suggest that overexpression of COP1 contributes to the accelerated degradation of p53 protein in cancers and attenuates the tumor suppressor function of p53.
Conditional Expression of K-
ras
in an Epithelial Compartment that Includes the Stem Cells Is Sufficient to Promote Squamous Cell Carcinogenesis
Authors: Vitale-Cross Lynn , Amornphimoltham Panomwat , Fisher Galen , Molinolo Alfredo A. , Gutkind J. Silvio 
Published: September 2005

Abstract
Ras genes are the most frequently mutated oncogenes in human cancer. However, the contribution of ras to tumor initiation still is unclear because ras expression in primary cells can cause cell cycle arrest and even cell death by apoptosis. Furthermore, when expressed in the epidermis of mice, mutant ras promotes the formation of benign papillomas, only few of which will progress into carcinomas. However, in these cases, ras-transgene expression often is restricted to suprabasal or follicular epithelial cells that may lack self-renewal capacity. Thus, it still is conceivable that expression of active ras in other epithelial compartments may exert a distinct ability to promote malignant progression. To address this possibility, transgenic mice carrying the tetracycline-inducible system (tet-on receptor) targeted to the basal layer of stratified epithelium, which includes the epithelial stem cells, were engineered and crossed with mice expressing the K-rasG12D oncogene under the control of tet-regulated responsive elements. On doxycycline administration, proliferative lesions ranging from hyperplasias, papillomas, and dysplasias to metastatic carcinomas developed in squamous epithelia of the skin, oral mucosa, salivary glands, tongue, esophagus, forestomach, and uterine cervix within just 10 to 20 days. The most noticeable lesions were invasive squamous carcinomas of the skin and oral mucosa. These findings suggest that the expression of oncogenes in an epithelial compartment that includes the stem cells may be sufficient to promote squamous carcinogenesis. They also provide a molecularly defined conditional animal model system in which the mechanisms responsible for cancer initiation, maintenance, and metastatic spread can be readily investigated.
Sixteenth Annual Pezcoller Symposium
Authors: Mihich Enrico , Jaenisch Rudolf 
Published: September 2005

Abstract
In the postgenomic era of cancer biology, it is becoming increasingly evident that epigenetic controls of gene expression play an important role in determining the phenotype of cancer cells, also indicating the possibility of restoring epigenetically a normal phenotype in cancer cells. Related to these mechanisms of control and their dynamic changes during carcinogenesis and tumor progression are the phenomena determining the relationships between stem cells and cancer cells. This symposium focused on epigenetic mechanisms affecting cancer development and possibly providing a basis for intervention. The basic biology of stem cells and the relationships between stem cells and cancer were discussed. Epigenetic control mechanisms affecting gene expression with emphasis on DNA methylation and histone function were considered. Therapeutic strategies stemming from the knowledge acquired in the basic topics discussed also were outlined.