bluuebunny/crossref_metadata_2025 huggingface dataset:
An epigenetic marker panel for screening and prognostic prediction of ovarian cancer
Authors: Su Her‐Young , Lai Hung‐Cheng , Lin Ya‐Wen , Chou Yu‐Ching , Liu Chin‐Yu , Yu Mu‐Hsien
Published: September 2008

Aberrant CpG island hypermethylation is a common finding of cancers, which might be detectable in the tissue or serum of affected patients. We analyzed DNA methylation by methylation‐specific polymerase chain reaction of 7 genes, which included secreted frizzled receptor proteins 1, 2, 4, 5 (SFRP1, 2, 4, 5), SRY‐box 1 (SOX1), paired box gene 1 (PAX1) and LIM homeobox transcription factor 1, alpha (LMX1A) in primary tumor samples from 126 patients with ovarian cancer, 75 with a benign tumor and 14 with borderline malignancy of an ovarian tumor, and in the serum from 26 patients with ovarian cancer and 20 with a benign tumor. Six of 7 genes had higher methylation rates in patients with ovarian cancer than in borderline malignancy or benign tumor (p < 0.001). The methylation of SFRP1, SFRP2, SOX1 and LMX1A genes correlated with recurrence and overall survival of ovarian cancer patients. Combining the data for SFRP1, SFRP2 and SOX1 genes gave a relative risk for recurrence of 3.19 (p = 0.013) in patients with at least one gene methylation, and combining the data for SFRP1, SOX1 and LMX1A gave an RR for cancer‐related death of 6.09 (p = 0.010). Methylation analysis of tissues and serum revealed a significant correlation (kappa values, 0.332–0.598) and a highly sensitivity and specificity rates (73.08 and 75%) as a screening marker. In conclusion, promoter hypermethylation of specific genes in critical pathways is common in ovarian cancer and has potential as a prognostic factor and a promising serum marker for early screening. © 2008 Wiley‐Liss, Inc.
Prevalence and frequency of circulating t(14;18)‐MBR translocation carrying cells in healthy individuals
Authors: Schüler Frank , Dölken Lars , Hirt Carsten , Kiefer Thomas , Berg Tobias , Fusch Gerhard , Weitmann K. , Hoffmann W. , Fusch Christoph , Janz Siegfried , Rabkin Charles S. , Dölken Gottfried
Published: September 2008

The t(14;18) translocation is a common genetic aberration that can be seen as an early step in pathogenesis of follicular lymphoma (FL). The significance of low level circulating t(14;18)‐positive cells in healthy individuals as clonal lymphoma precursors or indicators of risk is still unclear. We determined the age dependent prevalence and frequency of BCL2/IgH rearrangements in 715 healthy individuals ranging from newborns to octo‐ and nonagenarians. These results were compared with number of circulating t(14;18)‐positive cells in 108 FL patients at initial presentation. The overall prevalence of BCL2/IgH junctions in this large sample was 46% (327/715). However, there was a striking dependence upon age. Specifically, among individuals up to 10 years old, none had detectable circulating t(14;18)‐positive cells. In the age groups representing 10–50 years old, we found a steady elevation in the prevalence of BCL2/IgH junctions up to a prevalence of 66%. Further increases of the prevalence in individuals older than 50 years were not seen. The mean frequency of BCL2/IgH junctions in healthy individuals ≥40 years (18–26 × 10−6) was significantly higher than in younger subjects (7–9 × 10−6). Four percent (31/715) of individuals carried more than one t(14;18)‐positive cell per 25,000 peripheral blood mononuclear cells (PBMNCs). In comparison, 108 stage III/IV FL patients had a median number of circulating t(14;18)‐positive malignant FL cells of about 9200/1 million PBMNCs (range 7–1,000,000). These findings will further improve the understanding of the relevance of t(14;18)‐positive cells in healthy individuals as a risk marker toward the development into lymphoma precursors. © 2008 Wiley‐Liss, Inc.
Genomic instability and histone H3 phosphorylation induction by the Ras‐mitogen activated protein kinase pathway in pancreatic cancer cells
Authors: Espino Paula S. , Pritchard Susan , Heng Henry H.Q. , Davie James R.
Published: September 2008

Activating mutations in K‐Ras occur in most pancreatic cancers. We investigated whether genetic changes (K‐Ras mutations) in human pancreatic cancer cell lines altered genomic instability and epigenetic events responding to Ras‐mitogen activated protein kinase (MAPK) signaling by characterizing 3 human pancreatic cancer cells lines with and without activating mutations in K‐Ras. Activation of the Ras‐MAPK pathway results in the stimulation of the histone H3 kinase, mitogen and stress activated kinase (MSK) 1, and increased phosphorylation of histone H3 at serine 10 (H3 S10ph). MSK1 and H3 S10ph have roles in neoplastic transformation. We demonstrate that the presence of a K‐Ras mutation did not correlate with elevated chromosomal aberrations or increased genomic instability. Although the levels of the epidermal growth factor receptors and MSK were similar, the Ras‐MAPK pathway was differentially induced by phorbol esters (12‐O tetradecanoylphorbol‐13‐acetate) or epidermal growth factor, with the response of this signaling pathway being cell‐type specific. This response corresponded downstream at the level of chromatin where stimuli‐induced elevation of H3 S10ph typically paralleled the increase in phospho‐extracellular signal regulated kinase 1/2. Our results present evidence that nonclonal chromosomal aberrations and epigenetic programming responding to stimulation of the Ras‐MAPK pathway may be better markers for cancer progression than the upstream mutated oncogenes. © 2008 Wiley‐Liss, Inc.
Promoter hypermethylation correlates with the Hsulf‐1 silencing in human breast and gastric cancer
Authors: Chen Zhao , Fan Jie‐Qing , Li Jie , Li Qiu‐Shi , Yan Zhao , Jia Xue‐Ke , Liu Wei‐Dong , Wei Li‐Jun , Zhang Feng‐Zhi , Gao Hong , Xu Jun‐Pu , Dong Xiao‐Ming , Dai Jie , Zhou Hai‐Meng
Published: September 2008

The HSulf‐1 gene is an important factor that modulates the sulfation status of heparan sulfate proteoglycans (HSPGs) in the extracellular matrix, resulting in disturbance of HSPG‐related signal transduction pathways. Recently, HSulf‐1 has been reported to be down‐regulated in several human cancers. In this study, we first cloned and characterized the 5′ promoter region of the HSulf‐1 gene (around 400 bp) that contained high basal promoter activity. We also found that this functional promoter region was hypermethylated in a number of human cancer cell lines. Furthermore, we found that hypermethylation in this promoter region correlated with the down‐regulation of the HSulf‐1 expression in human breast and gastric cancer cell lines and tissue samples. These results suggest that the promoter hypermethylation may be one of the mechanisms of the HSulf‐1 gene silencing in human breast and gastric cancers. Finally, we demonstrated that the HSulf‐1 promoter was more frequently (p < 0.05) methylated in cell‐free DNA extracted from serum samples of human breast and gastric cancer patients than that of healthy people (76.2%, 55.0% and 19.0%, respectively), indicating that detection of the HSulf‐1 promoter methylation in serum samples may have clinical implications in early detection and diagnosis of human breast and gastric cancers. © 2008 Wiley‐Liss, Inc.
NDRG3 is an androgen regulated and prostate enriched gene that promotes in vitro and in vivo prostate cancer cell growth
Authors: Wang Weiqun , Li Yuhua , Li Yang , Hong Aizhen , Wang Jian , Lin Biaoyang , Li Runsheng
Published: September 2008

NDRG3 belongs to the N‐myc down‐regulated gene (NDRG) family that contains 4 paralogs: NDRG1, ‐2, ‐3 and ‐4. The function of NDRG3 and its relationship to cancer has not been studied. We herein report our examination of the expression and biological roles of NDRG3 in prostate cancers. We showed that NDRG3 expression is enriched in testis and prostate using gene expression data derived from massively parallel signature sequencing from 33 different human organs. We further showed that NDRG3 is expressed in both epithelial prostate cancer cells and prostatic stromal cells at both mRNA and proteins levels. We demonstrated that NDRG1 is significantly up‐regulated by androgen in LNCaP cells. Over‐expression of NDRG3 in stably transfected PC‐3 cells increased their growth rates and migration capabilities when compared to parental or mock empty vector transfected PC‐3 cells. In addition, we found that overexpresson of NDRG3 promoted the growth of xenograft tumors in nude mice. Finally, we found that NDRG3 expression was detected in 58.6% (41/70) of prostate cancer specimens compared to 13.2% (5/38) of benign prostatic hyperplasia specimens by immunohistochemistry. We showed by microarray and by RT‐PCR that NDRG3 overexpression up‐regulates the expression of many angiogenic chemokines including CXCL1 (chemokine ligand 1), CXCL3 (chemokine ligand 3) and CXCL5 (chemokine ligand 5), which may increase angiogenesis of tumors. Taken together, these results demonstrate that NDRG3 is a tumor promoter, the overexpression of which may contribute to the malignant phenotype of tumors. © 2008 Wiley‐Liss, Inc.
Reciprocal activating interaction between 6‐sulfo LacNAc+ dendritic cells and NK cells
Authors: Wehner Rebekka , Löbel Bärbel , Bornhäuser Martin , Schäkel Knut , Cartellieri Marc , Bachmann Michael , Rieber Ernst Peter , Schmitz Marc
Published: September 2008

Dendritic cells (DCs) display an extraordinary capacity to induce T‐cell responses providing the opportunity of DC‐based cancer vaccination strategies. Additional findings indicate that DCs may also play a crucial role for the activation of natural killer (NK) cells, which are important effectors in innate antitumor immunity. However, studies investigating the interaction between native human DCs and NK cells are limited. Recently, we defined 6‐sulfo LacNAc (slan) DCs as a major subpopulation of myeloid human blood DCs, which represent principal producers of the proinflammatory cytokines tumor necrosis factor‐α and interleukin (IL)‐12. Functional data revealed that slanDCs efficiently induce neoantigen‐specific CD4+ T cells and activate tumor‐reactive cytotoxic T cells. When evaluating the crosstalk between slanDCs and NK cells in this study, we found that lipopolysaccharide (LPS)‐activated slanDCs efficiently enhance NK cell CD69 expression and interferon (IFN)‐γ secretion. NK cell‐mediated tumor‐directed cytotoxicity was significantly improved by slanDCs. NK cell activation induced by slanDCs was critically dependent on IL‐12. When investigating the impact of NK cells on the immunostimulatory capacity of slanDCs, we observed that they promote DC maturation. In addition, NK cells strongly enhanced the secretion of immunomodulatory IL‐12 and reduced the release of immunosuppressive IL‐10 by slanDCs. IFN‐γ and cell‐to‐cell contact contributed to these effects. Furthermore, data revealed that DC‐NK cell crosstalk improves slanDC‐mediated differentiation of naïve CD4+ T lymphocytes into IFN‐γ‐producing Th1 cells. In conclusion, we demonstrate a reciprocal activating interaction between slanDCs and NK cells, which may play a pivotal role in the regulation of antitumor immunity. © 2008 Wiley‐Liss, Inc.
Inhibition of cyclin D1 expression by cyclin D1 shRNAs in human oral squamous cell carcinoma cells is associated with increased cisplatin chemosensitivity
Authors: Zhou Xiaojian , Zhang Zhiyuan , Yang Xiao , Chen Wantao , Zhang Ping
Published: September 2008

Cyclin D1 is a well‐known cell cycle regulator. Recently, its pro‐survival function has been revealed in several tumors. Because increasing expression of cyclin D1 is a common event in oral squamous cell carcinoma (OSCC) and has been correlated with cisplatin resistance, we investigated if cyclin D1 inhibition could increase cisplatin chemosensitivity of OSCC. Five cyclin D1 shRNAs were prepared and 3 were selected for subsequent experiments. IC50 values for cisplatin were determined by an MTT assay. Cisplatin‐induced apoptosis and cell cycle block were investigated. A tumor transplantation model was generated to examine the cisplatin sensitivity of Tca/cisplatin after in vivo cyclin D1 silencing. The role of nuclear factor‐κB (NF‐κB) and cyclin‐dependent kinase 4 (CDK4) in cyclin D1‐mediated cisplatin resistance was also examined. The most effective shRNA resulted in 84.51% knockdown of the cyclin D1 protein level. After the transfection with the 2 most effective shRNAs, the cisplatin IC50 decreased from 5.88 μg/ml to 1.36 μg/ml and 2.47 μg/ml, although overexpression of cyclin D1 rendered OSCC cells more resistant to cisplatin treatment (IC50 increased from 6.43 μg/ml to 12.24 μg/ml). This decreasing IC50 was correlated with the down‐regulation of cisplatin‐induced NF‐κB activity in cyclin D1 knockdown cells, and was independent of CDK4 function. In vivo tumor transplantation models also confirmed a cisplatin‐sensitizing effect of cyclin D1 shRNA in OSCC. A TUNEL assay validated the increase in apoptosis as induced by cisplatin in cyclin D1 knockdown cells. Cyclin D1 may be an important target for future therapy in patients with OSCC. © 2008 Wiley‐Liss, Inc.
Spatial clustering of childhood cancer in Great Britain during the period 1969–1993
Authors: McNally Richard J.Q. , Alexander Freda E. , Vincent Tim J. , Murphy Michael F.G.
Published: September 2008

The aetiology of childhood cancer is poorly understood. Both genetic and environmental factors are likely to be involved. The presence of spatial clustering is indicative of a very localized environmental component to aetiology. Spatial clustering is present when there are a small number of areas with greatly increased incidence or a large number of areas with moderately increased incidence. To determine whether localized environmental factors may play a part in childhood cancer aetiology, we analyzed for spatial clustering using a large set of national population‐based data from Great Britain diagnosed 1969–1993. The Potthoff‐Whittinghill method was used to test for extra‐Poisson variation (EPV). Thirty‐two thousand three hundred and twenty‐three cases were allocated to 10,444 wards using diagnosis addresses. Analyses showed statistically significant evidence of clustering for acute lymphoblastic leukaemia (ALL) over the whole age range (estimate of EPV = 0.05,p= 0.002) and for ages 1–4 years (estimate of EPV = 0.03,p= 0.015). Soft‐tissue sarcoma (estimate of EPV = 0.03,p= 0.04) and Wilms tumours (estimate of EPV = 0.04,p= 0.007) also showed significant clustering. Clustering tended to persist across different time periods for cases of ALL (estimate of between‐time period EPV = 0.04,p=0.003). In conclusion, we observed low level spatial clustering that is attributable to a limited number of cases. This suggests that environmental factors, which in some locations display localized clustering, may be important aetiological agents in these diseases. For ALL and soft tissue sarcoma, but not Wilms tumour, common infectious agents may be likely candidates. © 2008 Wiley‐Liss, Inc.
Reduction of TIP30 correlates with poor prognosis of gastric cancer patients and its restoration drastically inhibits tumor growth and metastasis
Authors: Li Xiaohua , Zhang Ying , Cao Shanshan , Chen Xiong , Lu Yuanyuan , Jin Haifeng , Sun Shiren , Chen Bei , Liu Jie , Ding Jie , Wu Kaichun , Fan Daiming
Published: September 2008

Gastric cancer is an aggressive cancer with poor prognosis. Identification of precise prognostic marker and effective therapeutic target is important in the treatment of gastric cancer. TIP30, a newly identified tumor suppressor, appears to be involved in multiple functions including tumorigenic suppression, apoptosis induction and diminishing angiogenic properties. Here, the level of TIP30 expression was determined in gastric cancer, and the impact of its alteration on cancer biology and clinical outcome was investigated. We found that TIP30 protein was absent or reduced in gastric cancer cell lines. There was also a loss or substantial decrease of TIP30 expression in 106 cases of gastric tumors as compared with that in normal gastric mucosa (p < 0.05), which was significantly associated with inferior survival duration. In a Cox proportional hazards model, TIP30 expression independently predicted better survival (p < 0.05). We also restored TIP30 protein expression in human gastric cancer‐derived cells AGS and MKN28 lacking endogenous TIP30 protein to study the effects of TIP30 expression on cell proliferation, cell kinetics, tumorigenicity and metastasis in BALB/c nude mice and found that adenoviral‐mediated restoration of TIP30 expression led to downregulation of cyclin D1, Bcl‐2, Bcl‐xl, but to upregulation of p27, Bax, p53, caspase 3 and 9 expression, cell cycle G0/G1 arrest and apoptosis in vitro, and dramatic attenuation of tumor growth and abrogation of metastasis in animal models. Taken together, the present work revealed a novel function of TIP30, which can possibly be used as an independent prognostic factor and a potential therapeutic target for gastric cancer. © 2008 Wiley‐Liss, Inc.
TOP2A overexpression in hepatocellular carcinoma correlates with early age onset, shorter patients survival and chemoresistance
Authors: Wong Nathalie , Yeo Winnie , Wong Wai‐Lap , Wong Navy L.‐Y. , Chan Kathy Y.‐Y. , Mo Frankie K.‐F. , Koh Jane , Chan Stephan Lam , Chan Anthony T.‐C. , Lai Paul B.‐S. , Ching Arthur K.‐K. , Tong Joanna H.‐M. , Ng Ho‐Keung , Johnson Philip J. , To Ka‐Fai
Published: September 2008

Genomic gain represents an important mechanism in the activation of proto‐oncogenes. In many instances, induced oncogenes hold clinical implications both as prognostic markers and targets for therapeutic design. In hepatocellular carcinoma (HCC), although chromosomal gains are common, information on underlying oncogenes induced remains minimal. Here, we examined 7 causal sites of HCC for overexpressed genes by array‐based transcriptional mapping. In 22 HCC cell lines and early passages of cultures studied, clusters of up‐regulated genes were indicated, where TOP2A expression ranked the highest. Distinct TOP2A transcriptions were confirmed in an independent series of HCC tumors relative to adjacent non‐tumoral liver (p = 0.0018). By tissue microarray analysis of 172 HCC, we found TOP2A expressions correlated with advance histological grading (p < 0.001), microvascular invasion (p = 0.004) and an early age onset of the malignancy (≤40 years; p = 0.007). In conjunction with P‐gp and MRP1, TOP2A were further assessed for its association with chemotherapy responsiveness and survival in 148 patients who entered our recently reported Phase III prospective randomized study. In 73 chemoresistant and 75 nonresistant patients, only TOP2A positivity correlated with chemoresistance (p = 0.029) and shorter patients survival (p < 0.0001). The potential therapeutic value in targeting TOP2A by Etoposide, as a single agent, and in combination with Doxorubicin was also explored. In vitro cytotoxic studies suggested Etoposide at IC20 readily reduced IC50 values of Doxorubicin by a magnitude of ∼3.5 to 10‐fold compared to Doxorubicin alone (p < 0.028). Our study highlighted for the first time the prognostic value of TOP2A in HCC and the potential use of TOP2A reactive agents in therapy. © 2008 Wiley‐Liss, Inc.
Grading the severity of cervical neoplasia based on combined histopathology, cytopathology, and HPV genotype distribution among 1,700 women referred to colposcopy in Oklahoma
Authors: Wentzensen Nicolas , Schiffman Mark , Dunn S. Terence , Zuna Rosemary E. , Walker Joan , Allen Richard A. , Zhang Roy , Sherman Mark E. , Wacholder Sholom , Jeronimo Jose , Gold Michael A. , Wang Sophia S.
Published: September 2008

Diagnosis and treatment of cervical cancer precursors rely on colposcopic biopsy, which is sometimes hampered by incorrect biopsy placement and the unclear prognostic value of poorly reproducible diagnoses such as cervical intraepithelial neoplasia (CIN) Grade 1 and 2. Searching for discrete disease categories that incorporate the value of cytology and that reflect the causal role of particular HPV types, we analyzed histology, cytology and HPV genotype distributions in the Study to Understand Cervical Cancer Endpoints and Early Determinants (SUCCEED). This cross‐sectional study comprises ∼1,700 women referred to colposcopy or treatment for the spectrum of cervical disease, including 439 women with <CIN1, 429 CIN1, 322 CIN2, 297 CIN3 and 107 with cancer. Using hierarchical clustering of histology‐cytology groups based on HPV genotype distributions, we could plainly distinguish in this referral population 5 increasingly severe diagnostic groups of HPV‐positive women: (i) HPV‐positive women with <CIN2 histology and normal cytology, (ii) HPV positive women with <CIN2 histology and ASC or LSIL cytology; (iii) CIN2, including histologic CIN2 and HSIL cytology with any histology <CIN2; (iv) CIN3; and (v) invasive cervical cancer. The grouping of women with HSIL cytology, but without histological abnormalities to women with CIN2 suggests that in these cases the worst lesion was missed during colposcopy‐biopsy. We are now using these sharpened diagnostic categories to search for novel biomarkers predicting the risk of progression and invasion. © 2008 Wiley‐Liss, Inc.
High expression of 90K (Mac‐2 BP) is associated with poor survival in node‐negative breast cancer patients not receiving adjuvant systemic therapies
Authors: Tinari Nicola , Lattanzio Rossano , Querzoli Patrizia , Natoli Clara , Grassadonia Antonino , Alberti Saverio , Hubalek Michael , Reimer Daniel , Nenci Italo , Bruzzi Paolo , Piantelli Mauro , Iacobelli Stefano ,   on behalf of the Consorzio Interuniversitario Nazionale per la Bio‐Oncologia (CINBO)
Published: September 2008

90K (Mac‐2 BP) expression was evaluated by immunohistochemistry in paraffin‐embedded tissue from a consecutive series of lymph‐node negative breast cancer patients who did not receive adjuvant systemic treatment. An independent series of patients served as validation set. The association of 90K expression with risk of recurrence and death was examined in survival analyses together with known prognostic factors. High levels of 90K expression (IHC score > 8) were observed in 43 (25.3%) of 170 tumors examined. We found elevated risks of distant recurrence and overall mortality in patients with high 90K expression compared with patients with low 90K expression in their tumors. This increase persisted after adjusting for other prognostic factors in multivariate analysis (hazard ratio = 4.084; p < 0.001 for recurrence; hazard ratio = 4.298; p < 0.001 for death). These findings were confirmed in the validation set. Therefore, evaluation of 90K expression may be beneficial to identify lymph‐node negative breast cancer patients at lower risk of disease recurrence and death. © 2008 Wiley‐Liss, Inc.
Risk of cancer in first‐ and second‐degree relatives of testicular germ cell tumor cases and controls
Authors: Chia Victoria M. , Li Yan , Goldin Lynn R. , Graubard Barry I. , Greene Mark H. , Korde Larissa , Rubertone Mark V. , Erickson Ralph L. , McGlynn Katherine A.
Published: September 2008

Risk factors for testicular germ cell tumors (TGCT) have not been well identified; however, data suggest that risks of cancer in family members of men with TGCT is elevated. Using family history data from 738 cases and 904 controls enrolled in the U.S. Servicemen's Testicular Tumor Environmental and Endocrine Determinants (STEED) Study from 2002 to 2005, the risk of cancer in first‐ and second‐degree family members of these men was examined. Relative risks (RRs) and 95% confidence intervals (CIs) were estimated using Cox proportional hazards models, adjusting for reference age of case or control, race/ethnicity of case or control, sex of family member and lineage (maternal vs. paternal). An increased risk of all cancer among first‐degree relatives of cases compared to controls was observed (RR = 1.17, 95% CI: 1.01–1.35). There were suggestions of differences in risk when stratifying all relatives by lineage. For maternal relatives, there was a statistically significant increased risk of all cancer (RR = 1.16, 95% CI: 1.04–1.30), digestive tract (RR = 1.52, 95% CI: 1.15–2.00) and male genital organ cancer (RR = 1.70, 95% CI: 1.15–2.51); there was also a suggestion of increased risks of hematopoetic cancers, cancers in the female genital organs and nonmelanoma skin cancer. For paternal relatives, there was a statistically significant association only with decreased risk of lung cancer (RR = 0.69, 95% CI: 0.51–0.94). Thus, this study suggests that there may be aggregation of cancer among families of men diagnosed with TGCT. Published 2008 Wiley‐Liss, Inc.
Genetic and epigenetic inactivation of LPL gene in human prostate cancer
Authors: Kim Jin Woo , Cheng Yu , Liu Wennuan , Li Tao , Yegnasubramanian Srinivasan , Zheng Siqun L. , Xu Jianfeng , Isaacs William B. , Chang Bao‐Li
Published: September 2008

Lipoprotein lipase (LPL) is in chromosome 8p22, site of one of the most common somatic deletions in prostate tumors. Additionally, a CpG island (CGI) was identified in the LPL promoter region. To test the hypothesis that LPL is a tumor suppressor gene, which is inactivated by somatic deletion and hypermethylation in prostate cancer, we evaluated somatic DNA deletion and methylation status at LPL in 56 pairs of DNA samples isolated from prostate cancer tissues and matching normal controls and 11 prostate cell lines. We found that the DNA in 21 of 56 primary cancers (38%) was methylated in the LPL promoter CGI, whereas no methylation was detected in any normal samples. In addition, we found a hemizygous deletion at LPL in 38 of the 56 tumors (68%). When the results of deletion and methylation were considered together, we found LPL promoter CGI methylation occurred in 45% of LPL deleted tumors and in 22% of LPL retained tumors. Within several clinical characteristics tested, the preoperative PSA levels were found to be significantly higher in subjects with LPL promoter CGI methylation compared with subjects without LPL promoter methylation (p = 0.0012). Additionally, demethylation of the LPL promoter CGI was accompanied by transcriptional reactivation of LPL in the prostate cancer cell lines DU145 and PC3. In summary, we report a novel finding that the LPL gene is commonly methylated in prostate tumors, and our results suggest that biallelic inactivation of LPL by chromosomal deletion and promoter hypermethylation may play a role in human prostate cancer. © 2008 Wiley‐Liss, Inc.
Nuclear factor kappa B subunit p50 promotes melanoma angiogenesis by upregulating interleukin‐6 expression
Authors: Karst Alison M. , Gao Kai , Nelson Colleen C. , Li Gang
Published: September 2008

Nuclear factor kappa B (NF‐κB) signaling is deregulated in many tumor types, resulting in aberrant expression and/or activation of NF‐κB transcriptional complexes. We have previously reported that nuclear expression of the NF‐κB subunit p50 is strongly correlated with melanoma progression and poor 5‐year patient survival. In this study, we used cDNA microarray to analyze the gene expression profiles of melanoma cells overexpressing NF‐κB p50. We found that NF‐κB p50 expression strongly induced interleukin‐6 (IL‐6) upregulation in melanoma cells at both the transcriptional and translational levels and that IL‐6 production by melanoma cells enhanced the growth of endothelial cells in vitro. Expression of activating transcription factor 3 (ATF3), a negative regulator of IL‐6 gene transcription, inhibited p50‐mediated IL‐6 upregulation. Knockdown of p50 expression using lentiviral‐based shRNA abrogated IL‐6 induction in melanoma cells and inhibited its effects on endothelial cell growth. Finally, we used an in vivo matrigel plug assay to show that NF‐κB p50 overexpression promotes angiogenesis, while silencing NF‐κB p50 inhibits blood vessel formation. Our results demonstrate for the first time that the NF‐κB p50 subunit mediates melanoma angiogenesis by specifically upregulating IL‐6, highlighting a novel and important role for the NF‐κB p50/IL‐6 signaling axis in melanoma progression. © 2008 Wiley‐Liss, Inc.
UV‐induced EGFR signal transactivation is dependent on proligand shedding by activated metalloproteases in skin cancer cell lines
Authors: Singh Bhuminder , Schneider Matthias , Knyazev Pjotr , Ullrich Axel
Published: September 2008

Exposure to extensive ultraviolet (UV) rays is a major cause of skin cancer, which is thought to be initiated by DNA mutations. Members of the epidermal growth factor receptor (EGFR) family are important in various pathophysiologic processes like cancer and are shown to be phosphorylated upon UV exposure. Here we show that EGFR phosphorylation by modest UV doses is dependent on metalloprotease activity and resultant epidermal growth factor (EGF) family proligand shedding. This proligand cleavage releases the mature ligand, which then binds to and activates EGFR. We show that UV induced EGFR phosphorylation in transformed cell lines of melanocyte and keratinocyte origin, which was reduced upon preincubation with a broad‐spectrum metalloprotease inhibitor, BB94. UV also activated EGFR downstream signaling via Erk and Akt pathways in a BB94‐sensitive manner. Furthermore, using neutralizing antibodies we found that proligand amphiregulin was required for UV‐induced EGFR activation in SCC‐9 cells. Using RNAi this EGFR activation was further shown to depend on the metalloproteases ADAM9 and ADAM17 in SCC‐9 cells. cDNA array hybridization and RT‐PCR analysis showed overexpression of a Disintegrin and a Metalloproteases (ADAMs) and EGF family proligands in melanoma cell lines. Additionally, blocking EGFR signal transactivation by BB94 led to increased apoptosis in UV‐irradiated cells. EGFR signal transactivation also led to increased stability of the DNA repair protein, PARP, under UV stress. Thus, both antiapoptotic and DNA repair pathways are activated simultaneously by EGFR signal transactivation. Together, our data provide novel insights into the mechanism of UV‐induced EGFR activation, suggesting broad relevance of the UV‐ADAM‐proligand‐EGFR‐Erk/Akt pathway and its significance in skin cancer. © 2008 Wiley‐Liss, Inc.
p53 and p73 in suppression of Myc‐driven lymphomagenesis
Authors: Griesmann Heidi , Schlereth Katharina , Krause Michael , Samans Birgit , Stiewe Thorsten
Published: September 2008

Induction of apoptosis by the tumor suppressor p53 is known to protect from Myc‐driven lymphomagenesis. The p53 family member p73 is also a proapoptotic protein, which is activated in response to oncogenes like Myc. Here, we have investigated whether p73 provides a similar protection from Myc‐driven lymphomas as p53. Confirming previous studies, the inactivation of a single p53 allele (p53+/−) strongly reduced the median survival of Eμ‐Myc transgenic mice from 103 to 39 days and was invariably associated with a loss of the wild‐type p53 allele. In contrast, mutational inactivation of a p73 allele (p73+/−) reduced the median survival by only 12 days. Lymphomas that developed in the p73+/− background showed no loss of heterozygosity (LOH). Furthermore, gene expression profiling of p73+/+, p73+/− and p73−/− lymphomas indicated that p73+/− lymphomas retained p73 transcriptional activity. Subtle gene expression differences between p73+/+ and p73+/− lymphomas, however, suggest a haploinsufficient phenotype on some p73 target genes. This might help to explain why p73+/− animals succumbed to disease slightly earlier than their p73+/+ littermates (log‐rank test p < 0.0395) and why p73 often shows monoallelic inactivation in human lymphomas. Together these data demonstrate that in Myc‐driven lymphomagenesis p73 has weak tumor suppressor activity compared with p53. © 2008 Wiley‐Liss, Inc.
Joining the loops: β‐Globin gene regulation
Authors: Noordermeer Daan , de Laat Wouter
Published: September 2008

The mammalian β‐globin locus is a multigene locus containing several globin genes and a number of regulatory elements. During development, the expression of the genes changes in a process called “switching.” The most important regulatory element in the locus is the locus control region (LCR) upstream of the globin genes that is essential for high‐level expression of these genes. The discovery of the LCR initially raised the question how this element could exert its effect on the downstream globin genes. The question was solved by the finding that the LCR and activate globin genes are in physical contact, forming a chromatin structure named the active chromatin hub (ACH). Here we discuss the significance of ACH formation, provide an overview of the proteins implicated in chromatin looping at the β‐globin locus, and evaluate the relationship between nuclear organization and β‐globin gene expression. © 2008 IUBMB IUBMB Life, 60(12): 824–833, 2008
Expression of Concern: Laccase treatment impairs bisphenol A‐induced cancer cell proliferation affecting estrogen receptor α‐dependent rapid signals
Authors: Bolli Alessandro , Galluzzo Paola , Ascenzi Paolo , Del Pozzo Giovanna , Manco Immacolata , Vietri Maria Teresa , Mita Luigi , Altucci Lucia , Mita Damiano Gustavo , Marino Maria
Published: September 2008

A wide variety of environmental contaminants exert estrogenic actions in wildlife, laboratory animals, and in human beings through binding to nuclear estrogen receptors (ERs). Here, the mechanism(s) of bisphenol A (BPA) to induce cell proliferation and the occurrence of its bioremediation by treatment with laccase are reported. BPA, highly present in natural world and considered as a model of environmental estrogen action complexity, promotes human cancer cell proliferation via ERα‐dependent signal transduction pathways. Similar to 17β‐estradiol, BPA increases the phosphorylation of both extracellular regulated kinase and AKT. Specific inhibitors of these kinase completely block the BPA effect on cancer cell proliferation. Notably, high BPA concentrations (i.e., 0.1 and 1 mM) are cytotoxic even in ERα‐devoid cancer cells, indicating that an ERα‐independent mechanism participates to BPA‐induced cytotoxicity. On the other hand, BPA oxidation by laccase impairs the binding of this environmental estrogen to ERα loosing at all ERα‐dependent effect on cancer cell proliferation. Moreover, the laccase‐catalyzed oxidation of BPA reduces the BPA cytotoxic effect. Thus, laccase appears to impair BPA action(s), representing an invaluable bioremediation enzyme. © 2008 IUBMB IUBMB Life, 60(12): 843–852, 2008
R&D and subsidies at the firm level: an application of parametric and semiparametric two‐step selection models
Authors: Hussinger Katrin
Published: September 2008

This paper analyzes the effect of public R&D subsidies on firms' private R&D investment per employee and new product sales in German manufacturing. Parametric and semiparametric two‐step selection models are applied to this evaluation problem. The results show that the average treatment effect on the treated firms' R&D intensity is positive. The estimated effects are robust with respect to the different selection models. Further results show that publicly induced R&D spending is as productive as private R&D investment in generating new product sales. Copyright © 2008 John Wiley & Sons, Ltd.
Semiparametric hedonic price models: assessing the effects of agricultural nonpoint source pollution
Authors: Bontemps Christophe , Simioni Michel , Surry Yves
Published: September 2008

In the area of environmental analysis using hedonic price models, we investigate the performance of various nonparametric and semiparametric specifications. The proposed model specifications are made up of two parts: a linear component for house characteristics and a non‐(semi)parametric component representing the nonlinear influence of environmental indicators on house prices. We adopt a general‐to‐specific search procedure, based on recent specification tests comparing the proposed specifications with a fully nonparametric benchmark model, to select the best model specification. An application of these semiparametric models to rural districts indicates that pollution resulting from intensive livestock farming has a significant nonlinear impact on house prices. Copyright © 2008 John Wiley & Sons, Ltd.
Efficiency externalities of trade and alternative forms of foreign investment in OECD countries
Authors: Iyer Krishna G. , Rambaldi Alicia N. , Tang Kam Ki
Published: September 2008

The literature on the spillover effects of trade and inflows of foreign direct investment (FDI) has concentrated on technological externalities. Little effort has been directed towards identifying their efficiency externalities. This paper measures the efficiency externalities of trade and various forms of foreign investment for a sample of 20 OECD countries between 1982 and 2000 using a stochastic frontier approach. Trade and all foreign investment inflows are found to enhance efficiency, whereas outflows of FDI are found to exacerbate inefficiency. The efficiency externalities from foreign investment are contingent on the absorptive capacity of the host economies. Copyright © 2008 John Wiley & Sons, Ltd.
Random Recursive Partitioning: a matching method for the estimation of the average treatment effect
Authors: Porro Giuseppe , Iacus Stefano Maria
Published: September 2008

In this paper we introduce the Random Recursive Partitioning (RRP) matching method. RRP generates a proximity matrix which might be useful in econometric applications like average treatment effect estimation. RRP is a Monte Carlo method that randomly generates non‐empty recursive partitions of the data and evaluates the proximity between two observations as the empirical frequency they fall in a same cell of these random partitions over all Monte Carlo replications. From the proximity matrix it is possible to derive both graphical and analytical tools to evaluate the extent of the common support between data sets. The RRP method is “honest” in that it does not match observations “at any cost”: if data sets are separated, the method clearly states it.

The match obtained with RRP is invariant under monotonic transformation of the data. Average treatment effect estimators derived from the proximity matrix seem to be competitive compared to more commonly used estimators. RRP method does not require a particular structure of the data and for this reason it can be applied when distances like Mahalanobis or Euclidean are not suitable, in the presence of missing data or when the estimated propensity score is too sensitive to model specifications. Copyright © 2008 John Wiley & Sons, Ltd.
The wages of BMI: Bayesian analysis of a skewed treatment–response model with nonparametric endogeneity
Authors: Kline Brendan , Tobias Justin L.
Published: September 2008

We generalize the specifications used in previous studies of the effect of body mass index (BMI) on earnings by allowing the potentially endogenous BMI variable to enter the log wage equation nonparametrically. We introduce a Bayesian posterior simulator for fitting our model that permits a nonparametric treatment of the endogenous BMI variable, flexibly accommodates skew in the BMI distribution, and whose implementation requires only Gibbs steps. Using data from the 1970 British Cohort Study, our results indicate the presence of nonlinearities in the relationships between BMI and log wages that differ across men and women, and also suggest the importance of unobserved confounding for our sample of males. Copyright © 2008 John Wiley & Sons, Ltd.
Human umbilical cord mesenchymal stem cells: Osteogenesis in vivo as seed cells for bone tissue engineering
Authors: Diao Yinze , Ma Qingjun , Cui Fuzhai , Zhong Yanfeng
Published: September 2008

Mesenchymal stem cells (MSCs) are ideal seed cells for bone tissue engineering. However, intrinsic deficiencies exist for the autologous transplantation strategy of constructing artificial bone with MSCs derived from bone marrow of patients. In this study, MSCs‐like cells were isolated from human umbilical cords and were expanded in vitro. Flow cytometric analysis revealed that cells from the fourth passage were positive for CD29, CD44, CD71, CD73, CD90, and CD105 whereas they were negative for CD14, CD34, CD45, and CD117. Furthermore, these cells expressed HLA‐A, B, C (MHC‐I), but not HLA‐DP, DQ, DR (MHC‐II), or costimulatory molecules such as CD80 and CD86. Following incubation in specific inductive media for 3 weeks, cultured cells were shown to possess potential to differentiate into adipogenic, osteogenic or chondrogenic lineages in vitro. The umbilical cord‐derived MSCs (UC‐MSCs) were loaded with a biomimetic artificial bone scaffold material before being implanted subcutaneously in the back of Balb/c nude mice for four to twelve weeks. Our results revealed that UC‐MSCs loaded with the scaffold displayed capacity of osteogenic differentiation leading to osteogenesis with human origin in vivo. As a readily available source of seed cells for bone tissue engineering, UC‐MSCs should have broad application prospects. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res, 2009
Enhanced biological stability of collagen with incorporation of PAMAM dendrimer
Authors: Zhong Shaoping , Yung Lin Yue Lanry
Published: September 2008

The crosslinking methods of collagen using glutaraldehyde (GTA) and 1‐ethyl‐3‐(3‐dimethyl aminopropyl) carbodiimide (EDC)/N‐hydroxysuccinimide (NHS) are frequently performed in biomedical applications, but both methods still have their own disadvantages, including the GTA cytotoxicity and low degree of EDC/NHS crosslinking. In this study, we incorporated polyamidoamine (PAMAM) dendrimer with surface amine groups into the two aforementioned crosslinking methods to improve the biostability and structural integrity of collagen. Fifty micromolar of dendrimer concentration was found to have negligible in vitro cytotoxicity and was used for EDC and GTA crosslinking of collagen. The collagenase digestion assay showed that the collagen scaffolds crosslinked in the presence of PAMAM exhibited a higher denature temperature and higher resistance against collagenase digestion compared with their counterparts without dendrimer. Cell proliferation with human conjunctival fibroblasts showed that the incorporation of PAMAM in EDC crosslinking significantly increased the proliferation. All the crosslinked scaffolds also exhibited higher structural stability than the noncrosslinked scaffold. Crosslinking with EDC and PAMAM together yielded substantially higher proliferation and may be a suitable collagen scaffold for biomedical applications. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res 2009
Flow perfusion culture of human fetal bone cells in large β‐tricalcium phosphate scaffold with controlled architecture
Authors: Wang Lin , Hu Yun‐Yu , Wang Zhen , Li Xiang , Li Di‐Chen , Lu Bing‐Heng , Xu Song‐Feng
Published: September 2008

One unsolved problem in bone tissue engineering is how to enable the survival and proliferation of osteoblastic cells in large scaffolds. In this work, large β‐tricalcium phosphate scaffolds with tightly controlled channel architectures were fabricated and a custom‐designed perfusion bioreactor was developed. Human fetal bone cells in third passage were seeded onto the scaffolds and cultured in static or flow perfusion conditions for up to 16 days. Compared with nonperfused constructs, flow perfused constructs demonstrated improved cells proliferation and differentiation according to cell viability, glucose consumption, alkaline phosphatase activity, and osteopontin. Moreover, after 16 days of perfusion culture, a homogenous layer composed of cells and mineralized matrix throughout the whole scaffold was observed by scanning electron microscopy and histological study. In contrast, cells were located only along the scaffold perimeter in static culture. These results demonstrated the feasibility and benefit of perfusion culture in conjunction with well‐defined three‐dimensional environment for large bone graft construction. Porous scaffold with controlled architecture can be a potential tool to evaluate the effects of scaffold specific geometry on fluid flow configuration and cell behavior under perfusion culture. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res, 2009
Antibiotic delivery system using nano‐hydroxyapatite/chitosan bone cement consisting of berberine
Authors: Zou Qin , Li Yubao , Zhang Li , Zuo Yi , Li Junfeng , Li Jidong
Published: September 2008

Different concentrations of berberine were mixed with nano‐hydroxyapatite/chitosan (n‐HA/CS) bone cement to generate an antibiotic drug delivery system for treatment of bone defects. Properties of the system such as setting time, compressive strength, surface morphology, phase compositions, drug release profiles and antimicrobial activity were also characterized. It was shown that the setting time of the cement ranged from 17.03 ± 0.50 min to 28.47 ± 0.96 min and the compressive strength changed from 184.00 ± 7.94 MPa to 120.33 ± 9.02 MPa with the increase of berberine. The XRD, IR, and SEM analyses suggested that berberine powders were stable in the bone cement in simulated body fluid (SBF). In vitro release of berberine from the bioactive bone cement pellets in SBF could last more than 4 weeks. The release profiles of 1.0 wt % berberine loaded bone cement followed the Higuchi equation at the infusion stage. The drug loaded pellets can inhibit bacterial growth (Staphylococcus aureus) at the standardized berberine minimum inhibitory concentration of 0.02 mg/mL during berberine release from 1 to 28 days. The n‐HA/CS bone cement only with 1.0 wt % berberine proved to be an efficient antibiotic drug delivery system. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res, 2009
Mixing conditions for cell scaffolds affect the bone formation induced by bone engineering with human bone marrow stromal cells, β‐tricalcium phosphate granules, and rhBMP‐2
Authors: Uchida Moritoshi , Agata Hideki , Sagara Hiroshi , Shinohara Yoshinori , Kagami Hideaki , Asahina Izumi
Published: September 2008

Bone regenerative medicine via tissue engineering is expected to be an alternative treatment for conventional autogenous bone graft, as it is less invasive. One of the best triads for bone engineering is bone marrow stromal cells, calcium phosphate ceramics, and bone morphogenetic protein (BMP). However, the optimal mixing conditions for BMP‐induced osteoblasts and ceramic granules remain unclear. Therefore, we investigated the effect of the mixing conditions for cell scaffolds on the bone‐forming potential. The cells were mixed with beta‐tricalcium phosphate (β‐TCP) granules followed by osteoblast induction with recombinant human BMP‐2 (rhBMP‐2) (first mixture), or were first induced with rhBMP‐2 on plastic dishes and then mixed with the β‐TCP granules (last mixture) just prior to the operation. Both the first and last mixtures were transplanted into nude mice subcutaneously, with the amount of bone formation analyzed histomorphometrically. In addition, cell numbers and alkaline phosphatase (ALP) activity before transplantation was determined in both the mixtures. In vitro analyses revealed that cell numbers were greater in the last mixture, whereas ALP activity was greater in the first mixture. In vivo analyses revealed that the first mixture was much more osteogenic than the last mixture with respect to new bone formation and osteocalcin synthesis. These data suggest that cell‐scaffold mixing conditions have a significant influence on the bone‐forming capacity via bone engineering and that first mixture might be the optimal condition for rhBMP‐2‐induction of human osteoblasts. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res, 2009