bluuebunny/crossref_metadata_2025 huggingface dataset:
MHC class I‐deficient metastatic tumor variants immunoselected by T lymphocytes originate from the coordinated downregulation of APM components
Authors: Garcia‐Lora Angel , Martinez Marisol , Algarra Ignacio , Gaforio Jose Juan , Garrido Federico
Published: July 2003

Previous reports from our group indicated that the MHC class I phenotype of metastatic lung colonies produced by a mouse fibrosarcoma tumor clone (B9) were, depending on the immune status of the host, MHC class I negative in immunocompetent mice and MHC class I positive in immunodeficient athymic nude/nude mice. Now we report the identification of the molecular alterations responsible for the changes of MHC class I molecules in both situations. Metastatic nodes were analyzed for the mRNA level of H‐2 class I and β2‐microglobulin genes, and several gene components of the major histocompatibility complex (MHC) class I antigen‐processing machinery (APM). These included the genes coding for the low‐molecular‐weight proteins LMP2, LMP7, LMP10, the transporter associated with antigen processing (TAP‐1, TAP‐2), and calnexin, calreticulin, tapasin, PA‐28‐α, PA‐28‐β, ERP‐59 and ER‐60. Analyses with RT‐PCR showed that TAP‐1, TAP2, LMP‐2, LMP7, LMP10, tapasin and calnexin mRNA specific for these genes was absent in metastases produced in immunocompetent mice. In contrast, similar techniques with mRNA preparations obtained from metastatic nodes from immunodeficient mice showed that the mRNA expression level of these genes was highly positive. Interestingly, the MHC class I‐positive or negative phenotypes of the metastatic colonies correlated with in vivo immunogenicity. H‐2 positive metastasis grew more slowly than the H‐2 negative ones when injected intrafootpat in syngeneic immunocompetent animals and were finally rejected. These results provide evidence of the role of T cells in immune surveillance against tumors and identify a mechanism targeted by antitumor T lymphocytes to generate MHC class I‐negative tumor escape variants. © 2003 Wiley‐Liss, Inc.
Treatment of patients with progressive unresectable metastatic melanoma with a heterologous polyvalent melanoma whole cell vaccine
Authors: Vilella Ramon , Benitez Daniel , Milà Jordi , Vilalta Antoni , Rull Ramon , Cuellar Francisco , Conill Carles , Vidal‐Sicart Sergi , Costa Josep , Yachi Eva , Palou Josep , Malvehy Josep , Puig Susana , Marti Rosa , Mellado Begoña , Castel Teresa
Published: July 2003

Unresectable metastatic melanoma has no elective treatment. Neither chemotherapy, intravenous IL‐2 nor biochemotherapy clearly improves the overall survival. Recent assays with therapeutic vaccines have been recently yielded promising results. Here, we describe the application, clinical tolerance and antitumoural activity of a heterologous polyvalent melanoma whole cell vaccine in patients with metastatic melanoma. Twenty‐eight AJCC stage III/IV melanoma patients with progressive unresectable metastatic disease were treated with our heterologous polyvalent melanoma whole cell vaccine between July 1, 1998 and July 1, 2002. All patients had already been unsuccessfully treated with high doses of IFN‐α2 and/or polychemotherapy and/or biochemotherapy and/or perfusion of extremities, or could not receive other treatments due to their age or underlying illness. Twenty‐three were assessable. The vaccine was constituted by 10 melanoma cell lines, derived from primary, lymph node and metastatic melanomas. Prior to intradermal inoculation, the cells were irradiated and mixed with BCG, and 50% were treated with DNFB. After a median follow‐up of 19 months, 26% of patients responded: 3 CR (18, 16+, and 26+ months), 2 PR (8 and 22 months) and 1 MR (36+ months). The median survival of the whole group was 20.2 months. None of the 28 patients initially included in the study presented significant toxicity. This vaccination program had specific antitumoural activity in advanced metastatic melanoma patients and was well tolerated. The clinical responses and the median survival of our group of patients, together with the low toxicity of our polyvalent vaccine, suggest that this approach could be applied to earlier metastatic melanoma patients. © 2003 Wiley‐Liss, Inc.
Influence of drug‐induced apoptotic death on processing and presentation of tumor antigens by dendritic cells
Authors: Buttiglieri Stefano , Galetto Alessandra , Forno Sarah , De Andrea Marco , Matera Lina
Published: July 2003

Here we have studied the effects of apoptotic cell death induced by chemotherapic agents on tumor phagocytosis by dendritic cells (DC) and presentation of the relevant antigen to T lymphocytes. Annexin‐V‐FITC (Ann‐V) and propidium iodide (PI) staining was used to assess early apoptotic (Ann‐V+/PI−) vs. late apoptotic/secondary necrotic (Ann‐V+/PI+) death after a 24 hr observation of untreated and drug‐treated gastric carcinoma cells. After treatments, the HLA‐A*0201+ tumor cell line KATO III was exposed for 24 hr to allogeneic, HLA‐related GM‐CSF, IL‐4‐driven immature (i) DC. Tumor‐loaded iDC were tested for IL‐12 release in an ELISA assay, incubated with the DC‐maturating factor TNF‐α and used as stimulators for autologous T lymphocytes. Generation of antitumor T response against KATO cells was evaluated in an anti‐MHC class I MAb‐blocked Interferon‐γ ELISPOT assay. After treatment with Cis‐platin (cis), all dying cells were in early apoptosis, whereas secondary necrosis was the prevalent death pattern observed after epirubicin (epi) and doxorubicin (doxo). Doxo and epi increased tumor expression of heat shock protein (hsp) 70 and uptake of tumor cell components by DC, whereas cis treatment had no effect on hsp70 and was associated with poor tumor uptake by DC. Significant upmodulation of IL‐12 was observed by DC that had taken up the doxo‐ and epi‐treated tumors (p< 0.005 and p< 0.01, respectively). Increased IFN‐γ release was also observed after stimulation of T lymphocytes with DC loaded with doxo‐ and epi‐treated (p< 0.02 and p< 0.005, respectively) but not with cis‐treated DC. These data show that the products of early apoptosis cannot efficiently cross‐activate MHC class I‐restricted anti‐tumor lymphocytes even in the presence of DC maturating factors, whereas secondary necrosis is associated with robust T cell response. © 2003 Wiley‐Liss, Inc.
Polymorphisms in the CYP1A1 gene are associated with prostate cancer risk
Authors: Chang Bao‐li , Zheng Siqun L. , Isaacs Sarah D. , Turner Aubrey , Hawkins Gregory A. , Wiley Kathy E. , Bleecker Eugene R. , Walsh Patrick C. , Meyers Deborah A. , Isaacs William B. , Xu Jianfeng
Published: July 2003

CYP1A1 is likely to play an important role in the etiology of CaP through its function in activating environmental procarcinogens and catalyzing the oxidative metabolites of estrogens. To test the hypothesis that genetic polymorphisms in the CYP1A1 gene may be associated with the risk for CaP, we compared the allele, genotype and haplotype frequencies of 3 SNPs (3801T>C, 2455A>G and 2453C>A) of CYP1A1 among 159 HPC probands, 245 sporadic CaP cases and 222 unaffected men. Two SNPs (3801T>C and 2455A>G) were each individually associated with CaP risk when the allele and genotype frequencies were compared between CaP patients and unaffected controls. Furthermore, a combined SNP analysis using a haplotype approach revealed an even stronger association in Caucasians. Specifically, 4 major haplotypes (T‐A‐C, C‐A‐C, C‐G‐C and T‐A‐A) accounted for 99.8% of all observed haplotypes. These 4 haplotypes correspond to the previously described nomenclature (CYP1A1*1A, CYP1A1*2A, CYP1A1*2B and CYP1A1*4). The frequencies of these 4 haplotypes were significantly different among CaP patients and controls. The haplotype T‐A‐C (CYP1A1*1A) was significantly associated with increased risk for CaP, and the haplotype C‐A‐C (CYP1A1*2A) was significantly associated with decreased risk for CaP. These findings suggest that genetic polymorphisms in CYP1A1 may modify the risk for CaP. © 2003 Wiley‐Liss, Inc.
Alterations of RB1, p53 and Wnt pathways in hepatocellular carcinomas associated with hepatitis C, hepatitis B and alcoholic liver cirrhosis
Authors: Edamoto Yoshihiro , Hara Akira , Biernat Wojciech , Terracciano Luigi , Cathomas Gieri , Riehle Hans‐Martin , Matsuda Masanori , Fujii Hideki , Scoazec Jean‐Yves , Ohgaki Hiroko
Published: July 2003

Major etiologic factors associated with human hepatocellular carcinomas (HCCs) include infection with hepatitis C (HCV) and hepatitis B virus (HBV), excess alcohol intake and aflatoxin B1 exposure. While the G→T p53 mutation at codon 249 has been identified as a genetic hallmark of HCC caused by aflatoxin B1, the genetic profile associated with other etiologic factors appears to be less distinctive. In our study, we screened HCCs resulting from HCV infection (51 cases), HBV infection (26 cases) or excess alcohol intake (23 cases) for alterations in genes involved in the RB1 pathway (p16INK4a, p15INK4b, RB1, CDK4 and cyclin D1), the p53 pathway (p53, p14ARF and MDM2) and the Wnt pathway (β‐catenin, APC). Alterations of the RB1 pathway, mainly p16INK4a methylation, loss of RB1 expression and cyclin D1 amplification, were most common (69–100% of cases). There was a significant correlation between loss of RB1 expression and RB1 methylation. All 24 HCCs with RB1 promoter methylation lacked RB1 expression, while none of the 67 cases with RB1 expression exhibited RB1 methylation (p < 0.0001), suggesting that promoter methylation is a major mechanism of loss of RB1 expression in HCCs. Alterations of the p53 pathway consisted mostly of p53 mutations or p14ARF promoter methylation (20–48%). Mutations of the p53 gene were found at a similar frequency (13–15%) in all etiologic groups, without any consistent base change or hot spot. Mutations of β‐catenin were found in 13–31% of cases, while no APC mutations were detected in any of the HCCs analyzed. With the exception of only 3 of 39 cases (8%), cyclin D1 amplification and β‐catenin mutations were mutually exclusive, supporting the view that cyclin D1 is a target of the Wnt signaling pathway. Overall, the RB1, p53 and Wnt pathways were commonly affected in HCCs of different etiology, probably reflecting common pathogenetic mechanisms, i.e., chronic liver injury and cirrhosis, but tumors associated with alcoholism had more frequent alterations in the RB1 and p53 pathways than those caused by HCV infection. © 2003 Wiley‐Liss, Inc.
Expression of Concern: The retinoblastoma protein interacts with Bag‐1 in human colonic adenoma and carcinoma derived cell lines
Authors: Arhel Nathalie J. , Packham Graham , Townsend Paul A. , Collard Tracey J. , H‐Zadeh Akram M. , Sharp Adam , Cutress Ramsey I. , Malik Karim , Hague Angela , Paraskeva Chris , Williams Ann C.
Published: July 2003

Although the retinoblastoma susceptibility gene RB1 is inactivated in a wide range of human tumours, overexpression in colonic carcinomas has been linked to the antiapoptotic function of the protein. In the current study we show that the Retinoblastoma susceptibility protein (Rb) protein interacts with Bag‐1, an apoptotic regulator, in human colonic adenoma‐ and carcinoma‐derived cell lines. Coimmunoprecipitation demonstrated that endogenous Rb and Bag‐1 interact in both adenoma‐ and carcinoma‐derived cell lines. The specificity of the interaction was demonstrated by expression of human Papillomavirus E7 oncoprotein, an inhibitor of Rb protein interactions, which disrupted the Rb/Bag‐1 complex. We report that Bag‐1 is predominantly localised in the nucleus of colorectal adenoma‐ and carcinoma‐derived epithelial cells. Disruption of the Rb/Bag‐1 complex through expression of E7 changes the subcellular distribution of Bag‐1, decreasing nuclear localised Bag‐1. Our work establishes that the Rb protein interacts with the Bag‐1 apoptotic regulator protein, and introduces a novel function for Rb, involving modulation of the subcellular localisation of Bag‐1 in human colonic epithelial cells. © 2003 Wiley‐Liss, Inc.
Green tea and risk of breast cancer in Asian Americans
Authors: Wu Anna H. , Yu Mimi C. , Tseng Chiu‐Chen , Hankin Jean , Pike Malcolm C.
Published: July 2003

There is substantial in vitro and in vivo evidence implicating tea polyphenols as chemopreventive agents against various cancers. However, epidemiologic data obtained from mainly Western populations are not supportive of a protective role of tea, mainly black tea, in the etiology of breast cancer. Much less is known about the relationship between green tea and breast cancer risk. During 1995–1998, we conducted a population‐based, case‐control study of breast cancer among Chinese, Japanese and Filipino women in Los Angeles County and successfully interviewed 501 breast cancer patients and 594 control subjects. Detailed information on menstrual and reproductive factors; dietary habits, including intake of black and green tea; and other lifestyle factors was collected. Risk of breast cancer was not related to black tea consumption. In contrast, green tea drinkers showed a significantly reduced risk of breast cancer, and this was maintained after adjusting for age, specific Asian ethnicity, birthplace, age at menarche, parity, menopausal status, use of menopausal hormones, body size and intake of total calories and black tea. Compared to women who did not drink green tea regularly (i.e., less than once a month), there was a significant trend of decreasing risk with increasing amount of green tea intake, adjusted odds ratios being 1.00, 0.71 (95% confidence interval [CI] 0.51–0.99) and 0.53 (95% CI 0.35–0.78), respectively, in association with no, 0–85.7 and >85.7 ml of green tea per day. The significant inverse association between risk of breast cancer and green tea intake remained after further adjustment for other potential confounders, including smoking; alcohol, coffee and black tea intake; family history of breast cancer; physical activity; and intake of soy and dark green vegetables. While both green tea and soy intake had significant, independent protective effects on breast cancer risk, the benefit of green tea was primarily observed among subjects who were low soy consumers. Similarly, the protective effect of soy was primarily observed among subjects who were nondrinkers of green tea. In summary, our results point to an important role of both green tea and soy intake in relation to breast cancer risk in Asian‐American women. © 2003 Wiley‐Liss, Inc.
Expression profiling reveals that methylation of TIMP3 is involved in uveal melanoma development
Authors: van der Velden Pieter A. , Zuidervaart Wieke , Hurks Monique H.M.H. , Pavey Sandra , Ksander Bruce R. , Krijgsman Elise , Frants Rune R. , Tensen Cornelis P. , Willemze Rein , Jager Martine J. , Gruis Nelleke A.
Published: July 2003

Uveal melanoma is associated with a high tumor‐related mortality due to the propensity to develop metastases. The mechanisms that are responsible for malignant dissemination are largely unknown and need to be explored to facilitate diagnosis and treatment of metastases. To identify molecules involved in dissemination, we used cell lines derived from a primary uveal melanoma and 2 liver metastases from the same patient as a model for tumor progression. Using a microarray representing 1,176 genes, we identified 63 differentially expressed genes. Forty genes showed a higher expression and 23 showed a lower expression in the primary cell line compared to the metastasis cell lines. These genes are involved in processes like angiogenesis, apoptosis, macrophage stimulation, and extracellular matrix regulation. In contrast, the 2 liver metastasis cell lines produced nearly identical expression profiles. Demethylation of the primary melanoma cell line by 5‐aza‐2′deoxycytidine treatment revealed that 19 genes were suppressed by hypermethylation. An important finding was the 5‐fold decreased expression of TIMP3 in the metastatic cell lines, a molecule involved in extracellular matrix degradation. We demonstrate in the cell lines that TIMP3 expression is regulated by methylation. These observations were confirmed in primary uveal melanoma and suggests a role for TIMP3 in uveal melanoma development. © 2003 Wiley‐Liss, Inc.
Obesity and hormone‐dependent tumors: Cohort and co‐twin control studies based on the Swedish Twin Registry
Authors: Jonsson Fredrik , Wolk Alicja , Pedersen Nancy L. , Lichtenstein Paul , Terry Paul , Ahlbom Anders , Feychting Maria
Published: July 2003

Obesity increases the risk of certain cancer types, e.g., cancer of the endometrium, colon and gallbladder. For some other cancer forms, e.g., prostate cancer, the association is less clear. We examined the association between body mass index (BMI) and hormone‐dependent tumors, utilizing a cohort of 21,884 Swedish twins born during 1886–1925. Information about BMI at different ages and potential confounding factors was collected prospectively. The Swedish Cancer Registry was used to identify cases of cancer in the prostate (n = 666), breast (n = 607), corpus uteri (n = 150) and ovary (n = 118) during 1969–1997. The material was analyzed as a traditional cohort and with co‐twin control analyses that allow for control of genetic influences. Obesity (BMI ≥30 kg/m2) at baseline was positively associated with cancer in the corpus uteri [relative risk (RR) = 3.03, 95% confidence interval (CI) 1.82–5.03], as was BMI at age 25, independently of BMI at baseline. Increased risk was also found for breast cancer but only in older women (≥70 years). Overweight at age 25 was associated with decreased risk of breast cancer (RR = 0.51, 95% CI 0.33–0.78). No association was found for prostate cancer. We conclude that age is an important effect modifier of cancer risk associated with obesity and that obesity and overweight in young adult life may affect cancer risk also later in life. © 2003 Wiley‐Liss, Inc.
Nitric oxide‐mediated promotion of mammary tumour cell migration requires sequential activation of nitric oxide synthase, guanylate cyclase and mitogen‐activated protein kinase
Authors: Jadeski Lorraine C. , Chakraborty Chandan , Lala Peeyush K.
Published: July 2003

Using clonal derivatives of spontaneous mammary tumours in C3H/HeJ mice, we had earlier shown that tumour‐derived nitric oxide (NO), resulting from endothelial type (e) NO synthase (NOS) expression by tumour cells, promoted tumour growth and metastasis by multiple mechanisms: stimulation of tumour cell invasiveness, migration and angiogenesis. Our present study examined the signaling mechanisms underlying NO‐mediated promotion of tumour cell migration in a highly metastatic and high eNOS‐expressing C3H/HeJ mammary tumour cell line, C3L5. C3L5 cell migration was reduced in the presence of NG‐nitro‐L‐arginine methyl ester (L‐NAME, NOS inhibitor) in a concentration‐dependent manner and restored in the additional presence of excess L‐arginine (NOS substrate), confirming a migration‐promoting role of endogenous NO. Migratory capacity of C3L5 cells was reduced after treatment with the guanylate cyclase (GC) inhibitor 1‐H‐[1,2,4]oxadiaxolo[4,3‐a]quinolalin‐1‐one (ODQ) and restored in the additional presence of 8‐bromoguanosine 3′5′‐cyclic monophosphate (8‐Br cGMP, cGMP analogue), demonstrating a pivotal role for GC in C3L5 cell migration. Mitogen‐activated protein kinase kinase (MAPKK; MEK) inhibitor, UO126, blocked migration, demonstrating MEK involvement in C3L5 cell migration. Furthermore, both ODQ and UO126 blocked migration‐restoring effects of L‐arginine in L‐NAME‐treated cells, indicating that GC and MAPK pathways are required for endogenous NO‐mediated migratory responses. Similarly, L‐NAME reduced and additional treatment with excess L‐arginine or sodium nitroprusside (SNP, NO donor) stimulated phosphorylation of extracellular signal‐regulated kinases (ERK1/2), demonstrating a role for endogenous and exogenous NO in ERK1/2 activation. ODQ inhibited ERK1/2 activation, whereas 8‐Br cGMP stimulated ERK1/2 phosphorylation in L‐NAME‐treated cells, indicating that cGMP is a downstream effector of NOS for ERK1/2 activation. Finally, both ODQ and UO126 blocked the capacity of L‐arginine to restore ERK1/2 phosphorylation in L‐NAME‐treated cells, demonstrating that GC and MEK are both required for endogenous NO‐mediated MAPK activation. Together, these results indicate sequential activation of NOS, GC and MAPK pathways in mediating signals for C3L5 cell migration, an essential step in invasion and metastasis. Since NOS activity is positively associated with human breast cancer progression, the present results are relevant for development of therapeutic modalities for this disease. © 2003 Wiley‐Liss, Inc.
Prevalence of BRCA1 and BRCA2 germline mutations in young breast cancer patients: A population‐based study
Authors: de Sanjosé Silvia , Léoné Mélanie , Bérez Victoria , Izquierdo Angel , Font Rebeca , Brunet Joan M. , Louat Thierry , Vilardell Loreto , Borras Joan , Viladiu Pau , Bosch F. Xavier , Lenoir Gilbert M. , Sinilnikova Olga M.
Published: July 2003

Our aim was to estimate the prevalence of mutations in the BRCA1 and BRCA2 genes among unselected incident cases of breast cancer in young women. We identified 158 incident breast cancer cases diagnosed before age 46 years in predefined geographic areas in Girona and Tarragona, Spain, during 1995–1997. Of these, 136 (86%) provided information on family history of cancer and were screened for BRCA1 and BRCA2 mutations. Nine of the 136 (6.6%) were found to carry BRCA deleterious mutations (MUT) (1 BRCA1 and 8 BRCA2), and 20 were detected with rare BRCA variants of unknown significance (UV). Both MUT and US BRCA alterations were more frequent in younger patients: 7 (11.6%) MUT and 12 (19.3%) UV carriers were found in the group of 62 patients younger than 40 years, whereas 2 (2.7%) MUT and 9 (12%) US carriers were identified in the group of 74 patients aged 40–45. Family history of breast and ovarian cancers suggestive of hereditary condition (at least 2 first‐ or second‐degree relatives affected with breast cancer or at least 1 relative affected with ovarian cancer or early‐onset breast cancer) was absent for 5 of 9 MUT carriers. This suggests that BRCA screening policies based on family history of cancer would miss a considerable proportion of BRCA mutations. Mutations in the BRCA1 and BRCA2 genes explain at least 10% of breast cancer cases diagnosed before age 40 years. The contribution of these genes to early‐onset breast cancer is likely to be even higher given that certain UV cases might be disease‐associated. © 2003 Wiley‐Liss, Inc.
Detection of micrometastatic breast cancer by means of real time quantitative RT‐PCR and immunostaining in perioperative blood samples and sentinel nodes
Authors: Schröder Carolien P. , Ruiters Marcel H.J. , de Jong Steven , Tiebosch Anton T.M.G. , Wesseling Jelle , Veenstra Rense , de Vries Jaap , Hoekstra Harold J , de Leij Lou F.M.H. , de Vries Elisabeth G.E.
Published: July 2003

The aim of our study was to detect micrometastatic breast cancer by epithelial glycoprotein‐2 (EGP‐2) and cytokeratin 19 (CK19), using immunostaining and real time quantitative reverse transcriptase‐polymerase chain reaction (qRT‐PCR). Fifty‐eight breast cancer patients, 52 primary tumors, 75 sentinel nodes (SN) and 149 peripheral blood (PB) samples (from before, during and 4 days after operation) were examined. Immunostaining was performed with antibodies directed against EGP‐2 and CK19. Detection limits were one Michigan Cancer Foundation‐7 (MCF‐7) breast cancer cell line cell/2.106 leukocytes (immunostaining) and one MCF‐7 cell/106 leukocytes qRT‐PCR. Control noncancer lymph nodes (n = 10) showed nonspecific CK19 staining, but were qRT‐PCR negative; control healthy volunteer PB (n = 11) was always negative. Primary tumor samples, all positive with immunostaining, showed a wide variation of EGP‐2 (>104 fold) and CK19 mRNA expression (>103 fold). SN (n = 19) from 16 patients were tumor‐positive with routine haematoxylin‐eosin (H&E) and/or immunostaining. SN tumor presence was positively correlated to qRT‐PCR expression, but 3 tumor‐positive SN were false negative with qRT‐PCR. Three SN were qRT‐PCR positive, while tumor negative with H&E and/or immunostaining. No immunostaining positive PB was observed, but 19 patients (33%) had one or more qRT‐PCR positive PB samples. We concluded that primary tumors have varying expressions of EGP‐2 and CK19 mRNA. Both markers can be used in qRT‐PCR to obtain adequate sensitivity for single tumor cell detection. In SN, immunostaining appears more sensitive/specific than H&E or qRT‐PCR for tumor detection. No immunostaining positivity was found in PB, while 33% of patients had qRT‐PCR positive PB. The clinical value of these findings will have to be clarified. © 2003 Wiley‐Liss, Inc.
Survey and Assessment in Women's Colleges: An Issue of Context
Authors: Langdon Emily A. , Giovengo Annette L.
Published: June 2003

This chapter outlines the history of women's colleges and concludes with a case study of institutional assessment that provides insights for research and analysis.
Student Assessment in Tribal Colleges
Authors: Oritz Anna M. , Boyer Paul
Published: June 2003

The unique culture and traditions of Native American communities affect student outcomes and attendance patterns. The interpretation of assessment and accountability mechanisms needs to account for these contextual issues.
Development of the vomeronasal receptor epithelium and the accessory olfactory bulb in sheep
Authors: Salazar Ignacio , Lombardero Matilde , Alemañ Nuria , Sánchez Quinteiro Pablo
Published: July 2003

The morphological development of the vomeronasal organ (VNO) and accessory olfactory bulb (AOB) of the sheep from anlage to birth were studied by classical and histochemical methods using embryos and fetuses obtained from an abattoir with ages estimated from crown‐to‐rump length. Both VNO and AOB developed in a biologically logical sequence and completed their morphological development around day 98, at entry into the last third of the gestation period. A lectin with specificity for oligomeric N‐acetylglucosamine labeled the sensory epithelium of the VNO, the vomeronasal nerves, and the nervous and glomerular layers of the AOB before birth. These results suggest that the vomeronasal system, which is well developed and functional in adult sheep, may be able to function at or even before birth in these animals (whereas in rodents, for example, this is precluded by the AOB not completing its development until after birth). Microsc. Res. Tech. 61:438–447, 2003. © 2003 Wiley‐Liss, Inc.
Glacier variations in Breheimen, southern Norway: dating Little Ice Age moraine sequences at seven low‐altitude glaciers
Authors: Winkler Stefan , Matthews John A. , Shakesby Richard A. , Dresser P. Quentin
Published: June 2003

Moraine sequences in front of seven relatively low‐altitude glaciers in the Breheimen region of central southern Norway are described and dated using a ‘multi‐proxy’ approach to moraine stratigraphy. Lichenometric dating, based on theRhizocarponsubgenus, is used to construct a composite moraine chronology, which indicates eight phases of synchronous moraine formation:AD1793–1799, 1807–1813, 1845–1852, 1859–1862, 1879–1885, 1897–1898, 1906–1908 and 1931–1933. Although the existence of a few cases of older moraines, possibly dating from earlier in the eighteenth or late in the seventeenth centuries cannot be ruled out by lichenometry, Schmidt hammer R‐values from boulders on outermost moraine ridges suggest an absence of Holocene moraines older than the Little Ice Age. Twenty‐three radiocarbon dates from buried soils and peat associated with outermost moraines at three glaciers—Tverreggibreen, Storegrovbreen and Greinbreen—also indicate that the ‘Little Ice Age’ glacier maximum was the Neoglacial maximum at most if not all glaciers. Severalmaximumage estimates for the Little Ice Age glacier maximum range between the fifteenth and seventeenth centuries, with the youngest from a buried soil beingAD1693. A pre‐Little Ice Age maximum cannot be ruled out at Greinbreen, however, where the age of buried peat suggests the outermost moraine dates fromAD981–1399 (at variance with the lichenometric evidence). Glaciofluvial stratigraphy at Tverreggibreen provides evidence for minor glacier advances aboutAD655–963 andAD1277–1396, respectively. Copyright © 2003 John Wiley & Sons, Ltd.
Palaeotemperature reconstructions of the European permafrost zone during marine oxygen isotope Stage 3 compared with climate model results
Authors: van Huissteden Ko , Vandenberghe Jef , Pollard David
Published: June 2003

A palaeotemperature reconstruction based on periglacial phenomena in Europe north of approximately 51 °N, is compared with high‐resolution regional climate model simulations of the marine oxygen isotope Stage 3 (Stage 3) palaeoclimate. The experiments represent Stage 3 warm (interstadial), Stage 3 cold (stadial) and Last Glacial Maximum climatic conditions. The palaeotemperature reconstruction deviates considerably for the Stage 3 cold climate experiments, with mismatches up to 11 °C for the mean annual air temperature and up to 15 °C for the winter temperature. However, in this reconstruction various factors linking climate and permafrost have not been taken into account. In particular a relatively thin snow cover and high climatic variability of the glacial climate could have influenced temperature limits for ice‐wedge growth. Based on modelling the 0 °C mean annual ground temperature proves to be an appropriate upper temperature limit. Using this limit, mismatches with the Stage 3 cold climate experiments have been reduced but still remain. We therefore assume that the Stage 3 ice wedges were generated during short (decadal time‐scale) intervals of extreme cold climate, below the mean temperatures indicated by the Stage 3 cold climate model simulations. Copyright © 2003 John Wiley & Sons, Ltd.
Systematic regulation of spine sizes and densities in pyramidal neurons
Authors: Konur Sıla , Rabinowitz Daniel , Fenstermaker Vivian L. , Yuste Rafael
Published: June 2003

Dendritic spines receive most excitatory inputs in the CNS. Recent evidence has demonstrated that the spine head volume is linearly correlated with the readily releasable pool of neurotransmitter and the PSD size. These correlations can be used to functionally interpret spine morphology. Using Golgi impregnations and light microscopy, we reconstructed 23,000 spines from pyramidal neurons in layers 2/3, 4, 5 and 6 of mouse primary visual cortex and CA1 hippocampal region and measured their spine head diameters and densities. Spine head diameters and densities are variable within and across cells, although they are similar between apical and basal dendrites. When compared to other regions, layer 5 neurons have larger spine heads and CA1 neurons higher spine densities. Interestingly, we detect a correlation between spine head diameter and interspine distance within and across cells, whereby larger spines are spaced further away from each other than smaller spines. Finally, in CA1 neurons, spine head diameters are larger, and spine density lower, in distal apical dendrites (>200 μm from soma) compared to proximal regions. These results reveal that spine morphologies and densities, and therefore synaptic properties, are jointly modulated with respect to cortical region, laminar position, and, in some cases, even the position of the spine along the dendritic tree. Individual neurons also appear to regulate their apical and basal spine densities and morphologies in concert. Our data provide evidence for a homeostatic control of excitatory synaptic strength. © 2003 Wiley Periodicals, Inc. J Neurobiol 56: 95–112, 2003
A composite transformation for numerical integration of singular integrals in the BEM
Authors: Yun Beong In
Published: June 2003

In this paper we present a composite non‐linear transformation of a polynomial transformation (PT) and a sigmoidal transformation (ST) by the name of CT_PS (composite transformation with polynomial and sigmoidal transformations). This new transformation can be used for both Cauchy principal value (CPV) integrals and weakly singular integrals with interior singularities. Moreover, it is implied that the numerical evaluation using CT_PS would be more efficient than either PT or ST used alone. By numerical examples, we show that the presented CT_PS method, with the Gauss–Legendre quadrature rule, improves the approximation errors of the existing methods effectively. In particular, it is demonstrated that the results of the present method are excellent for CPV integrals with near end point singularities. Copyright © 2003 John Wiley & Sons, Ltd.
Determination of amplicon boundaries at 20q13.2 in tissue samples of human gastric adenocarcinomas by high‐resolution microarray comparative genomic hybridization
Authors: Weiss Marjan M , Snijders Antoine M , Kuipers Ernst J , Ylstra Bauke , Pinkel Daniel , Meuwissen Stefan GM , van Diest Paul J , Albertson Donna G , Meijer Gerrit A
Published: July 2003

Comparative genomic hybridization (CGH) of gastric adenocarcinomas frequently shows gains and amplifications of chromosome 20. However, the underlying genetic lesion is unknown and conventional CGH results do not allow specification of the target region. In order to investigate this chromosomal aberration with a higher resolution and sensitivity, microarray‐based CGH was performed with both scanning and high‐resolution arrays of chromosome 20 in a series of 27 gastric adenocarcinomas. Locus‐specific fragments of genomic DNA from bacterial artificial chromosome (BAC) clones were spotted as microarrays. A scanning array contained a set of 27 BAC clones covering chromosome 20q. A high‐resolution array contained 27 overlapping BAC clones at 20q13.2. This high‐resolution array was used to narrow down the amplicon at 20q13.2 in tumours showing amplification of this chromosomal region with the scanning array. Positive copy number changes on chromosome 20q were detected in 12 of 27 cases (44%). These changes included gain of the whole arm of chromosome 20q in 8 of 27 (30%) cases, amplification restricted to 20q12.1 in one case, and amplifications restricted to 20q13 in three cases (11%). The three tumours showing amplification restricted to 20q13 were analysed further using the high‐resolution array. In one tumour, the whole contig was amplified at a constant level. One of the other two tumours had a clear proximal breakpoint, while the other tumour had a clear distal breakpoint within the 20q13.2 region. The proximal and the distal breakpoint were approximately 800 kb apart. In the present study, an amplicon at 20q13.2 has been narrowed down to 800 kb which is likely to harbour one or more putative oncogenes relevant to gastric carcinogenesis, for which ZNF217 and CYP24 are good candidates. Copyright © 2003 John Wiley & Sons, Ltd.
Expression of TRAIL (TNF‐related apoptosis‐inducing ligand) and its receptors in normal colonic mucosa, adenomas, and carcinomas
Authors: Koornstra Jan J , Kleibeuker Jan H , van Geelen Caroline MM , Rijcken Fleur EM , Hollema Harry , de Vries Elisabeth GE , de Jong Steven
Published: July 2003

Tumour necrosis factor‐related apoptosis‐inducing ligand (TRAIL) induces apoptosis in tumour cell lines. Four membrane‐bound receptors for TRAIL have been identified, two apoptosis‐mediating receptors, DR4 and DR5, and two apoptosis‐inhibiting receptors, DcR1 and DcR2. The aim of this study was to examine the role of TRAIL and its receptors in colorectal cancer development. The immunohistochemical expression and localization of TRAIL and its receptors were investigated in normal mucosa (n = 10), adenomas (n = 19), and carcinomas (n = 21). Correlations between the expression of TRAIL and its receptors and the degree of apoptosis (assessed by M30 expression) and histopathological characteristics were explored. TRAIL and its receptors were expressed in normal mucosal epithelium. Expression of the receptors was seen in adenomas and carcinomas. TRAIL expression was lost in a subset of colorectal tumours, more frequently in carcinomas than in adenomas (p < 0.05). DR4 and DR5 staining was stronger in neoplastic cells than in normal cells and was accompanied by a higher degree of apoptosis. No differences were found between tumour and normal cells regarding DcR1 and DcR2 expression. No correlations were found between TRAIL or TRAIL receptor expression and histopathological characteristics. In conclusion, marked changes were seen in the course of the adenoma–carcinoma sequence with respect to the expression of TRAIL and TRAIL receptors DR4 and DR5. The stronger expression of DR4 and DR5 in neoplastic cells than in normal cells, together with a higher degree of apoptosis, suggests a possible functional role for these receptors in apoptosis induction in neoplastic colorectal cells. Copyright © 2003 John Wiley & Sons, Ltd.
Expression of VEGF, semaphorin SEMA3F, and their common receptors neuropilins NP1 and NP2 in preinvasive bronchial lesions, lung tumours, and cell lines
Authors: Lantuéjoul Sylvie , Constantin Bruno , Drabkin Harry , Brambilla Christian , Roche Joëlle , Brambilla Elisabeth
Published: July 2003

Two receptors, neuropilin 1 (NP1) and neuropilin 2 (NP2), bind class 3 semaphorins, axon guidance molecules including SEMA3F, the gene for which was isolated from a 3p21.3 deletion in lung cancer. In addition, they bind VEGF (vascular endothelial growth factor), enhancing the effects of VEGF binding to KDR/Flk‐1. Elevated VEGF levels are associated with the loss and cytoplasmic delocalization of SEMA3F in lung cancer, suggesting competition for their NP1 and NP2 receptors. To determine the timing of these events, we compared by immunohistochemistry VEGF, SEMA3F, NP1 and NP2 expression in 50 preneoplastic lesions and 112 lung tumours. In preneoplastic lesions, VEGF increased from low‐grade to high‐grade dysplasia (p = 0.001) whereas SEMA3F levels remained low. NP1 and NP2 levels increased from dysplasia to microinvasive carcinoma (p = 0.0001) and correlated with VEGF expression (p = 0.04 and 0.0002, respectively). Non‐small cell lung carcinoma overexpressed VEGF and NP1 and NP2 significantly more often than neuroendocrine tumours including small cell lung carcinoma. SEMA3F loss or delocalization correlated with advanced tumour stage. Migrating cells overexpressed VEGF, SEMA3F, NP1 and NP2 with cytoplasmic delocalization of NP1 as demonstrated in an in vitro wound assay. These results demonstrate early alteration of the VEGF/SEMA3F/NP pathway in lung cancer progression. Copyright © 2003 John Wiley & Sons, Ltd.
Expression of the HER1–4 family of receptor tyrosine kinases in breast cancer
Authors: Witton Caroline J , Reeves Jonathan R , Going James J , Cooke Timothy G , Bartlett John MS
Published: July 2003

EGFr/HER1 and c‐erbB‐2/HER2 expression are associated with poor prognosis in breast cancer. The type I receptor tyrosine kinase (RTK) family to which they belong has four members (HER1–4). In this study, expression of HER1–4 and oestrogen receptor (ER) expression were determined by immunohistochemistry in 220 breast carcinomas. Elevated expression of HER1 was observed in 16.4%, HER2 in 22.8%, HER3 in 17.5%, and HER4 in 11.9% of these tumours. Patients whose tumours overexpressed HER1, 2 or 3 had reduced survival (p = <0.001), whereas those whose tumours overexpressed HER4 had increased survival (p = 0.013); 38.6% of cases overexpressed one or more of HER1, 2 or 3. HER4 was rarely overexpressed with other HERs (1.4% of cases). Cox's multiple regression analysis demonstrated that overexpression of HER1/2/3, HER4, and standard prognostic indicators independently affected survival. HER1–3 expression was related to ER negativity (p < 0.0001, χ2). Patients with ER‐positive, HER1–3‐positive tumours had a significantly poorer survival (p < 0.001) than those with ER‐positive/HER‐negative or HER4‐positive tumours. Expression of HER RTKs displays complex interactions between different family members. There is a strong interaction, in terms of survival, between HER expression and ER expression. The development of HER‐targeted agents (eg Herceptin, Iressa), and agents targeted at the downstream signalling pathways, therefore provides new possibilities in the treatment of breast cancer. Copyright © 2003 John Wiley & Sons, Ltd.
The dynamic extracellular matrix: intervention strategies during heart failure and atherosclerosis
Authors: Heeneman Sylvia , Cleutjens Jack P , Faber Birgit C , Creemers Esther E , van Suylen Robert‐Jan , Lutgens Esther , Cleutjens Kitty B , Daemen Mat J
Published: July 2003

The extracellular matrix is no longer seen as the static embedding in which cells reside; it has been shown to be involved in cell proliferation, migration and cell–cell interactions. Turnover of the different extracellular matrix components is an active process with multiple levels of regulation. Collagen, a major extracellular matrix constituent of the myocardium and the arterial vascular wall, is synthesized by (myo)fibroblasts in the myocardium and smooth muscle cells in the medial arterial vascular wall. Its degradation is controlled by proteinases, which include matrix metalloproteinases. This review will focus on the impact of fibrosis and especially collagen turnover on the progression of heart failure and atherosclerosis, two of the main cardiovascular pathologies. We will discuss data from human studies and animal models, with an emphasis on the effects of interventions on collagen synthesis and degradation. We conclude that there is a dynamic (dis)balance in the rate of collagen synthesis and degradation during heart failure and atherosclerosis, which makes the outcome of interventions not always predictable. Alternative approaches for intervening in collagen metabolism will be discussed as possible therapeutic intervention strategies. Copyright © 2003 John Wiley & Sons, Ltd.
Role of tissue stroma in cancer cell invasion
Authors: De Wever Olivier , Mareel Marc
Published: July 2003

Maintenance of epithelial tissues needs the stroma. When the epithelium changes, the stroma inevitably follows. In cancer, changes in the stroma drive invasion and metastasis, the hallmarks of malignancy. Stromal changes at the invasion front include the appearance of myofibroblasts, cells sharing characteristics with fibroblasts and smooth muscle cells. The main precursors of myofibroblasts are fibroblasts. The transdifferentiation of fibroblasts into myofibroblasts is modulated by cancer cell‐derived cytokines, such as transforming growth factor‐β (TGF‐β). TGF‐β causes cancer progression through paracrine and autocrine effects. Paracrine effects of TGF‐β implicate stimulation of angiogenesis, escape from immunosurveillance and recruitment of myofibroblasts. Autocrine effects of TGF‐β in cancer cells with a functional TGF‐β receptor complex may be caused by a convergence between TGF‐β signalling and β‐catenin or activating Ras mutations. Experimental and clinical observations indicate that myofibroblasts produce pro‐invasive signals. Such signals may also be implicated in cancer pain. N‐Cadherin and its soluble form act as invasion‐promoters. N‐Cadherin is expressed in invasive cancer cells and in host cells such as myofibroblasts, neurons, smooth muscle cells, and endothelial cells. N‐Cadherin‐dependent heterotypic contacts may promote matrix invasion, perineural invasion, muscular invasion, and transendothelial migration; the extracellular, the juxtamembrane and the β‐catenin binding domain of N‐cadherin are implicated in positive invasion signalling pathways. A better understanding of stromal contributions to cancer progression will likely increase our awareness of the importance of the combinatorial signals that support and promote growth, dedifferentiation, invasion, and ectopic survival and eventually result in the identification of new therapeutics targeting the stroma. Copyright © 2003 John Wiley & Sons, Ltd.
Tenascins: regulation and putative functions during pathological stress
Authors: Chiquet‐Ehrismann Ruth , Chiquet Matthias
Published: July 2003

In this review, we discuss the structure and function of the extracellular matrix protein family of tenascins with emphasis on their involvement in human pathologies. The article is divided into the following sections: Introduction: the tenascin family of extracellular matrix proteins; Structural roles: tenascin‐X deficiency and Ehlers–Danlos syndrome; Tenascins as modulators of cell adhesion, migration, and growth; Role of tenascin‐C in inflammation; Regulation of tenascins by mechanical stress: implications for wound healing and regeneration; Association of tenascin‐C with cancer: antibodies as diagnostic and therapeutic tools; Conclusion and perspectives. Copyright © 2003 John Wiley & Sons, Ltd.
Das ideale Quantenlabor: Bose‐Einstein‐Kondensation
Authors: Sengstock Klaus , Bongs Kai , Reichel Jakob
Published: June 2003

Bose‐Einstein‐Kondensate (BEC) sind extrem kalte Gase aus bosonischen Atomen, die sich alle im energetischen Grundzustand versammeln. Ein BEC ist ein perfektes Quantenlabor. Es bietet eine makroskopische Materiewelle aus vielen Tausend Teilchen an, die dem Experiment offen zugänglich ist. Das unterscheidet es von anderen makroskopischen Quantenzuständen wie der Suprafluidität oder der Supraleitung, denn diese verbergen sich in Flüssigkeiten oder Festkörpern. Das BEC ist also ein ideales Modellsystem, um diese und andere Phänomene der Quantenmechanik zu studieren. Neue Perspektiven eröffnet die schnelle Erzeugung und leichte Manipulation eines Kondensats auf einem Mikrochip. Dazu gehören auch vielfältige Anwendungen bis hin zum Quantencomputer.
Erstmalige Spektroskopie des Elements Fermium
Authors: Backe Hartmut , Sewtz Michael
Published: June 2003

Das Element Fermium (Z=100) wurde 1952 in den Überresten einer thermonuklearen Explosion entdeckt. Es ist das schwerste Element, das über sukzessiven Neutroneneinfang und Betazerfall hergestellt werden kann. Jetzt ließ sich erstmals die atomare Struktur spektroskopisch studieren. Dafür wurde eine 2 ng leichte Probe von 255Fm (Halbwertszeit 20,1 Stunden) am Hochfluss‐Kernreaktor des Oak Ridge National Laboratory, USA, produziert und nach Deutschland versandt [1].
A fully automated nanoelectrospray tandem mass spectrometric method for analysis of Caco‐2 samples
Authors: Van Pelt Colleen K. , Zhang Sheng , Fung Eliza , Chu Inhou , Liu Tongtong , Li Cheng , Korfmacher Walter A. , Henion Jack
Published: July 2003

Caco‐2 cells offer a means to rapidly screen permeability of drug candidates, allowing pharmaceutical companies to eliminate candidates unable to cross the intestinal barrier early in the discovery process. This screening process is typically performed by conventional liquid chromatography/tandem mass spectrometry (LC/MS/MS), which can require time‐consuming method development. An alternative to LC/MS/MS, automated nanoelectrospray tandem mass spectrometry (nanoESI‐MS/MS), is introduced. This novel approach requires an off‐line ZipTip™ desalting step followed by automated nanoESI‐MS/MS, using the NanoMate™ 100 and ESI Chip™. In addition to reduced method development time, automated nanoESI‐MS/MS also offers no carry‐over between samples, low sample consumption, and ease‐of‐use as compared with conventional pulled‐capillary nanoelectrospray. Furthermore, the infusion system described has the potential to be high‐throughput. A comparison of Caco‐2 samples analyzed both by LC/MS/MS and by automated nanoESI‐MS/MS is presented. The permeability and recovery data of the two compounds analyzed in this study obtained from conventional LC/MS/MS and by automated nanoESI‐MS/MS were in excellent agreement. Copyright © 2003 John Wiley & Sons, Ltd.