bluuebunny/crossref_metadata_2025_split huggingface dataset:
β-Catenin Functions Mainly as an Adhesion Molecule in Patients with Squamous Cell Cancer of the Head and Neck
Authors: Yu Ziwei , Weinberger Paul M. , Provost Elayne , Haffty Bruce G. , Sasaki Clarence , Joe J. , Camp R.L. , Rimm D.L. , Psyrri Amanda 
Published: September 2005

AbstractBackground: β-catenin, depending on subcellular localization, plays a dual role in carcinogenesis: as a signaling factor (in the nucleus) and as an adhesion molecule (in cell membrane). In this study, we sought to determine the role of β-catenin in head and neck carcinogenesis.Methods: First, we studied the incidence of mutations of β-catenin in a cohort of 60 head and neck squamous cell cancers (HNSCC). We subsequently evaluated the protein expression levels of β-catenin in a cohort of oropharyngeal squamous cell cancer tissue microarray using a novel in situ method of quantitative protein analysis and correlated those with cyclin D1 levels and clinical and pathologic data.Results: The mean follow-up time for survivors was 45 months and for all patients was 35 months. We found no mutations in the cohort of 60 HNSCC. β-catenin displayed primarily membranous expression pattern. Patients with high tumor-node-metastasis stage were more likely to have high expression of β-catenin (P = 0.040). Patients with low β-catenin expression had a local recurrence rate of 79% compared with 29% for patients with high β-catenin tumors (P = 0.0021). Univariate Cox regression revealed a hazard ratio for low β-catenin tumors of 3.6 (P = 0.004). Kaplan-Meier analysis showed that patients with low β-catenin expressing tumors trended toward worse 5-year disease-free survival (P = 0.06). In multivariate analysis, only β-catenin expression status was an independent prognostic factor (P = 0.044) for local recurrence. Tumors with high β-catenin had low cyclin D1 and vice versa (P = 0.007).Conclusions: The absence of activating β-catenin mutations combined with the inverse correlation between β-catenin levels with cyclin D1 levels and outcome suggest that β-catenin mainly functions as an adhesion and not signaling molecule in HNSCC.
Acquired Resistance to Imatinib in Gastrointestinal Stromal Tumor Occurs Through Secondary Gene Mutation
Authors: Antonescu Cristina R. , Besmer Peter , Guo Tianhua , Arkun Knarik , Hom Glory , Koryotowski Beata , Leversha Margaret A. , Jeffrey Philip D. , Desantis Diann , Singer Samuel , Brennan Murray F. , Maki Robert G. , DeMatteo Ronald P. 
Published: September 2005

Abstract
Most gastrointestinal stromal tumors (GIST) have an activating mutation in either KIT or PDGFRA. Imatinib is a selective tyrosine kinase inhibitor and achieves a partial response or stable disease in about 80% of patients with metastatic GIST. It is now clear that some patients with GIST develop resistance to imatinib during chronic therapy. To identify the mechanism of resistance, we studied 31 patients with GIST who were treated with imatinib and then underwent surgical resection. There were 13 patients who were nonresistant to imatinib, 3 with primary resistance, and 15 with acquired resistance after initial benefit from the drug. There were no secondary mutations in KIT or PDGFRA in the nonresistant or primary resistance groups. In contrast, secondary mutations were found in 7 of 15 (46%) patients with acquired resistance, each of whom had a primary mutation in KIT exon 11. Most secondary mutations were located in KIT exon 17. KIT phosphorylation was heterogeneous and did not correlate with clinical response to imatinib or mutation status. That acquired resistance to imatinib in GIST commonly occurs via secondary gene mutation in the KIT kinase domain has implications for strategies to delay or prevent imatinib resistance and to employ newer targeted therapies.
Potent Activity of a Novel Dimeric Heat Shock Protein 90 Inhibitor against Head and Neck Squamous Cell Carcinoma In vitro and In vivo
Authors: Yin Xiaoying , Zhang Hong , Burrows Francis , Zhang Lin , Shores Carol G. 
Published: September 2005

Abstract
Heat shock protein 90 (Hsp90) is a molecular chaperone that promotes the conformational maturation of numerous client proteins, many of which play critical roles in tumor cell growth and survival. The ansamycin-based Hsp90 inhibitor 17-allylamino-17-demethoxygeldanamycin (17-AAG) is currently in phase I/II clinical testing. However, 17-AAG is difficult to formulate and displays weak activity against some tumors. A novel dimeric ansamycin, EC5, was evaluated for antitumor activity in eight head and neck squamous cell carcinoma (HNSCC) cell lines. Both 17-AAG and EC5 inhibited tumor cell proliferation effectively, but EC5 was more potent, with IC50 below 200 nmol/L in most cell lines tested, including several lines that were resistant to 17-AAG. The inability of 17-AAG to kill JHU12 cells was linked to a defect in retinoblastoma signaling and could be rescued by ectopic expression of p16INK4a. EC5 induced G1 growth arrest of tumor cells and apoptosis, with the degradation of client proteins including epidermal growth factor receptor, c-Raf-1, Akt, and Cdk4 and inhibition of Akt phosphorylation. In vivo, EC5 dramatically reduced the growth rate of established HNSCC xenografts in nude mice and decreased expression of epidermal growth factor receptor and Akt within the xenografts. These results suggest that this novel ansamycin-based Hsp90 inhibitor affects multiple pathways involved in tumor development and progression and may represent a new strategy for the treatment of HNSCC patients.
Temozolomide Pharmacodynamics in Patients with Metastatic Melanoma: DNA Damage and Activity of Repair Enzymes O6-Alkylguanine Alkyltransferase and Poly(ADP-Ribose) Polymerase-1
Authors: Plummer E. Ruth , Middleton Mark R. , Jones Christopher , Olsen Anna , Hickson Ian , McHugh Peter , Margison Geoffrey P. , McGown Gail , Thorncroft Mary , Watson Amanda J. , Boddy Alan V. , Calvert A. Hilary , Harris Adrian L. , Newell David R. , Curtin Nicola J. 
Published: September 2005

Abstract
Purpose: Temozolomide, a DNA methylating agent used to treat melanoma, induces DNA damage, which is repaired by O6-alkylguanine alkyltransferase (ATase) and poly(ADP-ribose) polymerase-1 (PARP-1)–dependent base excision repair. The current study was done to define the effect of temozolomide on DNA integrity and relevant repair enzymes as a prelude to a phase I trial of the combination of temozolomide with a PARP inhibitor.
Experimental Design: Temozolomide (200 mg/m2 oral administration) was given to 12 patients with metastatic malignant melanoma. Peripheral blood lymphocytes (PBL) were analyzed for PARP activity, DNA single-strand breakage, ATase levels, and DNA methylation. PARP activity was also measured in tumor biopsies from 9 of 12 patients and in PBLs from healthy volunteers.
Results: Temozolomide pharmacokinetics were consistent with previous reports. Temozolomide therapy caused a substantial and sustained elevation of N7-methylguanine levels, a modest and sustained reduction in ATase activity, and a modest and transient increase in DNA strand breaks and PARP activity in PBLs. PARP-1 activity in tumor homogenates was variable (828 ± 599 pmol PAR monomer/mg protein) and was not consistently affected by temozolomide treatment.
Conclusions: The effect of temozolomide reported here are consistent with those documented in previous studies with temozolomide and similar drug, dacarbazine, demonstrating that a representative patient population was investigated. Furthermore, PARP activity was not inhibited by temozolomide treatment and this newly validated pharmacodynamic assay is therefore suitable for use in a proof-of-principle phase I trial a PARP-1 inhibitor in combination with temozolomide.
Detection of Human Papillomavirus Infection of the Cervix in Very Elderly Women Using PCR
Authors: Takubo Kaiyo , Shimomura-Izumiyama Naotaka , Koiwai Hidemi , Honma Naoko , Esaki Yukiyoshi , Yoshida Tomomi , Nakajima Takashi , Sawabe Motoji , Arai Tomio 
Published: September 2005

Abstract
Purpose: To determine the incidence of human papillomavirus (HPV) infection and the morphologic lesions induced by HPV infection of the uterine cervix in elderly Japanese women (including very elderly women) and to clarify the natural history and outcome of HPV infection.
Experimental Design: We detected squamous intraepithelial lesions (SIL) by cytology and the presence of HPV infection by PCR on cervical smears obtained at autopsy from 335 women ages 60 to 105 years (mean, 82.7 years). Two primers were used for PCR, one for low-risk HPV subtypes and one for high-risk HPV subtypes.
Results: SILs were observed in 20 (6.0%) of the women autopsied; 18 (5.4%) had low-grade SIL and 2 (0.6%) had high-grade SIL. HPV-DNA was not detected in any of the women with normal cervical cytology but was found in 9 (45.0%) of the 20 with SIL (2.7% of all subjects). Of these 9 women, 2 (22%) were positive for low-risk types of HPV and 7 (78%) were positive for high-risk types. All 9 had spent their last days in hospitals or nursing homes, the duration of institutional care ranging from 17 days to 10 years 2 months.
Conclusions: Our results suggest that HPV infection of the cervix may occasionally persist for long periods of time (the maximum duration noted in this study being 10 years 2 months). It is also possible that HPV infection in young women with normal cervical cytology will not persist into advanced age.
Coxsackie and Adenovirus Receptor Promotes Adenocarcinoma Cell Survival and Is Expressionally Activated after Transition from Preneoplastic Precursor Lesions to Invasive Adenocarcinomas
Authors: Brüning Ansgar , Stickeler Elmar , Diederich Daniel , Walz Lioba , Rohleder Hendrik , Friese Klaus , Runnebaum Ingo B. 
Published: September 2005

Abstract
Purpose: The cell adhesion protein, coxsackie and adenovirus receptor (CAR), is differentially expressed in various human adenocarcinomas. We analyzed the role of differential CAR expression during tumorigenesis and in cell survival of adenocarcinomas.
Experimental Design: In a murine mammary cancer model, a syngenic preneoplastic mammary tissue was implanted into the mammary fat pads of syngenic female BALB/c mice. CAR expression was determined by semiquantitative reverse transcription-PCR in the preneoplastic noninvasive precursor lesions and the developing invasive adenocarcinomas. Cell clones overexpressing CAR were generated and tested for their response to apoptotic factors and for the expression of apoptosis relevant proteins by reverse transcription-PCR and Western blot analysis.
Results: In comparison of preneoplastic precursor lesions with established adenocarcinomas, CAR expression was enhanced 2- to 5-fold in all six tissues which had survived and transformed into invasive adenocarcinomas. When stable CAR-overexpressing cell clones of the human cancer cell lines HeLa, CaSki, and A2780 were compared with the parental cell lines, 1.5- to 6-fold more cells survived application of tumor necrosis factor–related apoptosis-inducing ligand or growth factor withdrawal. CAR-enhanced cell survival was accompanied by reduced activation of caspase 3 and enhanced expression of bcl-2 or bcl-XL, depending on the cell type tested. Up-regulation of bcl-2 was found in all CAR-expressing adenocarcinomas of the murine cancer model.
Conclusions: CAR expression is enhanced after transition from preneoplastic precursor lesions to neoplastic mammary cancer outgrowths. Enhanced CAR expression can promote cancer cell survival. These data suggest differential expression of CAR as a new factor in tumorigenesis.
The Matrix Metalloproteinase-9/Neutrophil Gelatinase-Associated Lipocalin Complex Plays a Role in Breast Tumor Growth and Is Present in the Urine of Breast Cancer Patients
Authors: Fernández Cecilia A. , Yan Li , Louis Gwendolyn , Yang Jiang , Kutok Jeffery L. , Moses Marsha A. 
Published: September 2005

Abstract
Purpose: Having previously shown that the binding of neutrophil gelatinase-associated lipocalin (NGAL) to matrix metalloproteinase-9 (MMP-9) protects this extracellular matrix remodeling enzyme from autodegradation, we hypothesized that the addition of NGAL to breast cancer cells, which do not express this protein but do express MMP-9, might result in a more aggressive phenotype in vivo. Based on our previous reports that MMPs can be detected in the urine of cancer patients, we also asked whether MMP-9/NGAL could be detected in the urine of breast cancer patients and whether it might be predictive of disease status.
Experimental Design: Clones of MCF-7 human breast cancer cells differentially expressing NGAL were generated by stable transfection with human NGAL expression constructs. The established clones were then implanted s.c. in immunodeficient mice and tumor growth was monitored. In addition, we analyzed the urine of individuals with breast cancer and age-matched, sex-matched controls using gelatin zymography for the presence of MMP-9/NGAL.
Results: Increased NGAL expression resulted in significant stimulation of tumor growth. Immunohistochemical analysis of MCF-7 tumors revealed that the NGAL-overexpressing ones exhibited increased growth rates that were accompanied by increased levels of MMP-9, increased angiogenesis, and an increase in the tumor cell proliferative fraction. In addition, MMP-9/NGAL complex was detected in 86.36% of the urine samples from breast cancer patients but not in those from healthy age and sex-matched controls.
Conclusions: These findings suggest, for the first time, that NGAL may play an important role in breast cancer in vivo by protecting MMP-9 from degradation thereby enhancing its enzymatic activity and facilitating angiogenesis and tumor growth. Clinically, these data suggest that the urinary detection of MMP-9/NGAL may be useful in noninvasively predicting disease status of breast cancer patients.
Cyclooxygenase-2 Expression Correlates with Local Chronic Inflammation and Tumor Neovascularization in Human Prostate Cancer
Authors: Wang Wanzhong , Bergh Anders , Damber Jan-Erik 
Published: September 2005

Abstract
Purpose: Chronic inflammation is linked to the development of cancer in several organs, including the prostate. Up-regulated cyclooxygenase-2 (COX-2) may play a role in influencing cell proliferation, differentiation, apoptosis, or angiogenesis. This study aimed to derive data from human prostate cancer to investigate whether chronic inflammation and angiogenesis were correlated with the expression of COX-2.
Experimental Design: In this study, we did double-immunohistochemical analysis of a set of 43 human prostate cancer for COX-2 expression and the correlation with T-lymphocyte and macrophage densities and CD31-marked microvessel density (MVD) in situ.
Results: COX-2 positive staining was detected in 40/43 cancer samples with the very heterogeneous expression. Elevated COX-2 expression was associated with high Gleason score (P = 0.002). Foci of chronic inflammation were found in all 43 samples. COX-2–positive areas were noted with high T-lymphocyte and macrophage densities than COX-2–negative tumor areas (P &lt; 0.0001 and P = 0.001, respectively). MVD were also found higher in COX-2–positive areas than in COX-2–negative tumor areas (P = 0.001).
Conclusions: This study shows a novel relationship between COX-2 expression and the local chronic inflammation within prostate cancer and the increased angiogenesis. It is likely that the proinflmmatory cytokines, released by T-lymphocytes and macrophages, up-regulate COX-2 in adjacent tumor cells and stimulate the angiogenesis in stromal tissues. These findings suggest that COX-2 may be an effective therapeutic target in prostate cancer treatment.
Combined Dendritic Cell Cryotherapy of Tumor Induces Systemic Antimetastatic Immunity
Authors: Machlenkin Arthur , Goldberger Ofir , Tirosh Boaz , Paz Adrian , Volovitz Ilan , Bar-Haim Erez , Lee Sung-Hyung , Vadai Ezra , Tzehoval Esther , Eisenbach Lea 
Published: September 2005

Abstract
Purpose: Cryotherapy of localized prostate, renal, and hepatic primary tumors and metastases is considered a minimally invasive treatment demonstrating a low complication rate in comparison with conventional surgery. The main drawback of cryotherapy is that it has no systemic effect on distant metastases. We investigated whether intratumoral injections of dendritic cells following cryotherapy of local tumors (cryoimmunotherapy) provides an improved approach to cancer treatment, combining local tumor destruction and systemic anticancer immunity.
Experimental Designs: The 3LL murine Lewis lung carcinoma clone D122 and the ovalbumin-transfected B16 melanoma clone MO5 served as models for spontaneous metastasis. The antimetastatic effect of cryoimmunotherapy was assessed in the lung carcinoma model by monitoring mouse survival, lung weight, and induction of tumor-specific CTLs. The mechanism of cryoimmunotherapy was elucidated in the melanoma model using adoptive transfer of T cell receptor transgenic OT-I CTLs into the tumor-bearing mice, and analysis of Th1/Th2 responses by intracellular cytokine staining in CD4 and CD8 cells.
Results: Cryoimmunotherapy caused robust and tumor-specific CTL responses, increased Th1 responses, significantly prolonged survival and dramatically reduced lung metastasis. Although intratumor administration of dendritic cells alone increased the proliferation rate of CD8 cells, only cryoimmunotherapy resulted in the generation of effector memory cells. Furthermore, cryoimmunotherapyprotected mice that had survived primary MO5 tumors from rechallenge with parental tumors.
Conclusions: These results present cryoimmunotherapy as a novel approach for systemic treatment of cancer. We envisage that cryotherapy of tumors combined with subsequent in situ immunotherapy by autologous unmodified immature dendritic cells can be applied in practice.
Prognostic Role of Thymidylate Synthase Polymorphisms in Gastric Cancer Patients Treated with Surgery and Adjuvant Chemotherapy
Authors: Kawakami Kazuyuki , Graziano Francesco , Watanabe Go , Ruzzo Annamaria , Santini Daniele , Catalano Vincenzo , Bisonni Renato , Arduini Federica , Bearzi Italo , Cascinu Stefano , Muretto Pietro , Perrone Giuseppe , Rabitti Carla , Giustini Lucio , Tonini Giuseppe , Pizzagalli Francesca , Magnani Mauro 
Published: September 2005

Abstract
Purpose: To investigate the prognostic role of thymidylate synthase (TS) polymorphisms in gastric cancer patients treated with radical surgery and fluorouracil-based adjuvant chemotherapy.
Experimental Design: Ninety gastric cancer cases were identified among 187 patients previously enrolled in prospective case-control studies for disease susceptibility. Patients were genotyped for a G/C nucleotide change within a triple 28 bp variable number of tandem repeat sequence in the TS 5′-untranslated region (5′-UTR) and a 6 bp deletion in the TS 3′-untranslated region (3′-UTR). According to available functional data, patients with 5′-UTR 2R/2R, 2R/3C, 3C/3C genotypes were classified as low TS producers (5′-UTRlow) and patients with 5′-UTR 3G/3G, 3G/3C, 2R/3G genotypes as high TS producers (5′UTRhigh). Patients with 3′-UTR del6/del6 and del6/ins6 genotypes were classified as low TS producers (3′-UTRlow) and patients with 3′-UTR ins6/ins6 genotype as high TS producers (3′-UTRhigh). The prognostic analysis was based on 5′-UTR/3′-UTR combined genotypes.
Results: Ten patients (11%) were 5′-UTRhigh/3′-UTRhigh, 36 patients were 5′-UTRhigh/3′-UTRlow, 19 patients were 5′-UTRlow/3′-UTRhigh, and 25 patients were 5′-UTRlow/3′-UTRlow. 5′-UTRlow/3′-UTRlow patients showed the best outcome and the threshold of statistical significance was achieved in the comparison of disease-free survival and overall survival with 5′-UTRhigh/3′-UTRlow patients and 5′-UTRhigh/3′-UTRhigh patients. The presence of at least one high TS expression genotype showed independent adverse prognostic role in multivariate analysis.
Conclusions: The prognostic role of TS polymorphisms in gastric cancer deserves further investigation because the adverse effect of high TS expression genotypes may be a relevant information to improve adjuvant chemotherapeutic strategies.
Estrogen Receptor α Binds to Peroxisome Proliferator–Activated Receptor Response Element and Negatively Interferes with Peroxisome Proliferator–Activated Receptor γ Signaling in Breast Cancer Cells
Authors: Bonofiglio Daniela , Gabriele Sabrina , Aquila Saveria , Catalano Stefania , Gentile Mariaelena , Middea Emilia , Giordano Francesca , Andò Sebastiano 
Published: September 2005

Abstract
Purpose: The molecular mechanisms involved in the repressive effects exerted by estrogen receptors (ER) on peroxisome proliferator–activated receptor (PPAR) γ–mediated transcriptional activity remain to be elucidated. The aim of the present study was to provide new insight into the crosstalk between ERα and PPARγ pathways in breast cancer cells.
Experimental Design: Using MCF7 and HeLa cells as model systems, we did transient transfections and electrophoretic mobility shift assay and chromatin immunoprecipitation studies to evaluate the ability of ERα to influence PPAR response element–mediated transcription. A possible direct interaction between ERα and PPARγ was ascertained by coimmunoprecipitation assay, whereas their modulatory role in the phosphatidylinositol 3-kinase (PI3K)/AKT pathway was evaluated by determining PI3K activity and AKT phosphorylation. As a biological counterpart, we investigated the growth response to the cognate ligands of both receptors in hormone-dependent MCF7 breast cancer cells.
Results: Our data show for the first time that ERα binds to PPAR response element and represses its transactivation. Moreover, we have documented the physical and functional interactions of ERα and PPARγ, which also involve the p85 regulatory subunit of PI3K. Interestingly, ERα and PPARγ pathways have an opposite effect on the regulation of the PI3K/AKT transduction cascade, explaining, at least in part, the divergent response exerted by the cognate ligands 17β-estradiol and BRL49653 on MCF7 cell proliferation.
Conclusion: ERα physically associates with PPARγ and functionally interferes with PPARγ signaling. This crosstalk could be taken into account in setting new pharmacologic strategies for breast cancer disease.