bluuebunny/crossref_metadata_2025 huggingface dataset:
Granulocyte‐macrophage colony‐stimulating factor induces human melanoma‐cell migration
Authors: Kohn Elise C. , Hollister Gambrill H. , Liotta Lance A. , Schiffmann Elliott , Kohn Elise C. , Wahl Sharon , Dipersio John D.
Published: July 2010

Tumor metastasis is the primary cause of death for cancer patients. The metastatic cascade requires successful tumor cell invasion into and through vascular and parenchymal barriers. We have shown that autocrine motility factor (AMF, autotaxin) and the insulin‐like growth factors (IGFs) induce tumor‐cell migration. Since granulocyte‐macrophage colony‐stimulating factor (GM‐CSF) has been shown to prime neutrophils for chemotaxis, we have therefore studied the influence of GM‐CSF upon tumor cells and report that GM‐CSF stimulates migration of these cells in a dose‐dependent fashion. The ED50 for A2058 human melanoma cell line chemotaxis to GM‐CSF is approx. 60 pM. The motile response to GM‐CSF was additive to that of IGF‐1 and AMF, both of which are potent attractants for tumor cells. Pre‐treatment of cells for 2 hr with non‐toxic concentrations of pertussis toxin (PT) or amiloride resulted in a 50% inhibition of chemotaxis to GM‐CSF. Therefore, GM‐CSF, through PT‐ and amiloride‐sensitive signal pathways, is a potent attractant for melanoma cells, the response to which is additive to that of other attractants. The presence of the GM‐CSF receptor in A2058 melanoma cells was indicated by Northernblot analysis which identified message transcripts of 2.1 and 3.0 kb. These data emphasize the versatility of the melanoma cell migration response to an array of cytokines, including GM‐CSF.
Role of protein kinase c and cytokines on the function and production of cytolytic granules in αCD3‐activated killer‐cell‐mediated killing of tumor cells
Authors: Wu Jennifer , Hargrove Myrthel E. , Ting Chou‐Chik , Shiver John
Published: July 2010

The effects of PMA and staurosporine (PKC depletor/antagonist) and IL‐2/IL4 were used to determine the role of PKC and cytokine on αCD3‐induced activated killer cells (CD3‐AK). The present study examines their effects on the production of BLT‐esterase and on the effector function of CD3‐AK cells as well as the cytolytic granules. The production of BLT‐esterase generally correlated with the cytolytic activity of CD3‐AK cells and was reduced by PKC depletor/inhibitor but increased by IL‐4. In studying the effector function of CD3‐AK cells, we found that adding PMA or SSP at the effector phase inhibited the PKC‐dependent slow lysis. PMA, but not SSP, also reduced fast lysis, which was shown to be a PKC‐independent event. Additional experiments were performed to determine the effect of PKC on the lytic granules and to ascertain whether PMA has other effects on the effector‐to‐target relationship unrelated to PKC. It was found that neither PMA nor SSP affects the function of cytolytic granules, as measured by hemolytic assay against anucleated target (SRBC). These findings indicate that PKC has no direct effect on the granules. During testing against the nucleated tumor target through a novel approach using non‐cytolytic surrogate killers, the lytic activity of the granules was inhibited by PMA, suggesting that exocytosis or delivery of granules to nucleated target cells may require mobilization of intracellular Ca2+ in the killer cells, and this process is inhibited by PMA. Our findings indicate that PKC and cytokines regulate the production but not the lytic activity of cytolytic granules. Nonetheless, delivery of cytolytic granules from killer cells to the nucleated tumor target appears to be a Ca2+‐dependent event unrelated to PKC.
c‐myc Gene activation as a permanent trait of RSV‐infected quail cells
Authors: Sovová Vlasta , Fidlerová Helena , Hlozánek I. , Friis R.
Published: July 2010

A high level of c‐myc gene expression was found to be a constant feature of v‐src transformation. The c‐myc gene product was analyzed in quail embryo cells transformed by different mutants of Rous sarcoma virus (RSV) that were temperature‐sensitive with respect to various parameters of v‐src function. The high‐level expression of c‐myc proved not to be temperature‐sensitive: At both permissive (35°C) and non‐permissive (41°C) temperatures, the same high levels of c‐myc gene product were found for all RSV mutants tested. This result, in agreement with earlier evidence for a v‐src‐induced proliferative stimulus which was unaffected by ts mutants at the non‐permissive temperature, shows that certain v‐src functions have not yet been fully characterized.
T‐cell‐receptor engagement and tumor ICAM‐1 up‐regulation are required to by‐pass low susceptibility of melanoma cells to autologous CTL‐mediated lysis
Authors: Anichini Andrea , Mortarini Roberta , Parmiani Giorgio , Alberti Saverio , Mantovani Alberto
Published: July 2010

Tumor‐specific and non‐specific CD3+, TcRαβ+, CD8+ cytotoxic T‐cell (CTL) clones, isolated from tumor‐infiltrating lymphocytes (TIL) or peripheral blood lymphocytes (PBL) of a melanoma patient and allogeneic LAK cells, were used to investigate the requirements for bypassing the low lysability of some melanoma clones derived from an S.C. metastasis from which highly lysable clones were also obtained. Cytofluorimetric analysis showed that all melanoma clones expressed ICAM‐1, although to different extents, reaching a 10‐fold difference in fluorescence units, while HLA class‐1 antigens were similarly expressed. The differences in expression of ICAM‐1 among tumor clones correlated with differences in lysability, by both specific and non‐specific CTL, but were not large enough to affect lymphocyte‐tumor conjugate formation. Cytokine‐ or gene‐transfer‐mediated up‐regulation of ICAM‐1 did not induce de novo lysis of ICAM‐1low tumor cells; however, it markedly enhanced a low level of killing of the same cells by tumor‐specific, TcR‐dependent and HLA‐restricted CTL clones but not by non‐specific, TcR‐independent effectors. In addition, lysis of melanoma clones by any effector was similarly inhibited by anti‐ICAM‐1 and anti‐LFA‐1 antibodies. This indicates that by‐pass of low lysability of ICAM‐1low melanoma clones by CTL clones, after ICAM‐1 up‐regulation, is possible only if simultaneous LFA‐1 and TcR engagement takes place. In addition, these results suggest that the constitutive high level of expression of ICAM‐1 on the subset of ICAM‐1high melanoma cells must be only one of the factors contributing to the high lysability of these cells by any effector.
Over‐expression of c‐myc increases the sensitivity of epstein‐barr virus immortalized lymphoblastoid cells to non‐MHC‐restricted cytotoxicity
Authors: Cuomo Laura , Zhang Quian‐Jin , Torsteinsdottir Sigurbjörg , Klein George , Masucci Maria G. , Lombardi Luigia , Dalla‐Favera Riccardo
Published: July 2010

Epstein‐Barr virus (EBV)‐carrying Burkitt lymphoma (BL) lines which maintain the phenotypic characteristics of the in vivo tumor cells are more sensitive to natural (NK), interferonactivated (IAK) and IL‐2‐activated (LAK) cytotoxicity than EBV‐immortalized lymphoblastoid cell lines (LCL) of normal B‐cell origin. All BL cells carry chromosomal translocations which lead to deregulated expression of the c‐myc oncogene. LCLs transfected with constitutively active c‐myc alleles display changes in growth properties and surface phenotype. In this study, we have examined the effect of c‐myc deregulation on the sensitivity of LCLs to NK, IAK and LAK effectors. C‐myctransfected LCLs showed an increased sensitivity to lysis which correlated with the level of c‐myc expression. Expression of HLA class I and sensitivity to allospecific and EBV‐specific cytotoxic T‐lymphocytes (CTL) remained unchanged. Transfection of a constitutively active v‐H‐ras gene, which also induces changes in growth properties and cell‐surface phenotype, did not alter the sensitivity of LCLs to NK or LAK cytotoxicity.
Antenatal risk factors for malignant brain tumours in new south wales children
Authors: McCredie Margaret , Maisonneuve Patrick , Boyle Peter
Published: July 2010

A population‐based case‐control study of incident primary malignant brain tumours diagnosed during 1985 to 1989 in children aged 0 to 14 years was carried out in the coastal conurbation of New South Wales comprising Sydney, Wollon‐gong and Newcastle in the period 1988 to 1990. Personal interviews were conducted using a structured questionnaire with mothers of 82 cases and 164 control children individually matched to the cases by sex and age. Among the hypotheses being examined were those related to exposure to parental tobacco smoke, N‐nitroso compounds and possible protection from sources of vitamin C. No link was found with tobacco smoking by the mother before or during pregnancy. While exposure during pregnancy of the mother to tobacco smoke of the father appeared to double the risk of childhood brain tumours and a similar risk was found for father (but not mother) smoking before the index pregnancy, there was no “dose‐response” and the increased risk was confined to data supplied by the mother (rather than the father himself). The risk of childhood brain tumours rose with reported increasing consumption, during pregnancy, of cured meats, which have high levels of N‐nitroso compounds (or their precursors), and fell with rising consumption of vegetables. No association was found between the risk of childhood brain tumours and family history of epilepsy, cancer, or tumours of the nervous system, parental irradiation, previous miscarriage or procedures carried out during pregnancy, maternal consumption of antihistamines, barbiturates or diuretics, or maternal contact with cats or farm‐life during pregnancy. © 1994 Wiley‐Liss, Inc.
Perinatal and early postnatal risk factors for malignant brain tumours in New South Wales children
Authors: McCredie Margaret , Maisonneuve Patrick , Boyle Peter
Published: July 2010

A population‐based case‐control study of incident primary malignant brain tumours diagnosed during 1985–1989 in children aged 0 to 14 years was carried out in the coastal conurbation of New South Wales comprising Sydney, Wollon‐gong and Newcastle in the period 1988 to 1990. Personal interviews were conducted using a structured questionnaire with mothers of 82 cases and 164 control children individually matched to the cases by sex and age. Among the hypotheses examined were those related to: N‐nitroso compounds (sources included diet, dummies, medications, tobacco smoke); factors associated with the birth of the child; trauma to the head; and irradiation (X‐rays and electromagnetic radiation through electric blankets or water beds). Reported ever‐use of a dummy increased the risk of childhood brain tumours (OR = 2.9, 95% CI 1.6 to 5.4), although there did not appear to be any consistent indication of rising risk with reported increased levels of use. Compared with children who had never used a dummy, categories of use during the first year of life of a maximum of “no more than I hour per day or night”, “several hours per day or night”, and “most of the day or night” had statistically significant odds ratios of 2.6, 3.4, and 2.7 respectively. Consumption of fruit by the child before the age of one appeared to be protective. No association was found between childhood brain tumours and birth weight, being the first‐born child, or factors linked with the child's birth; head injuries; exposure to X‐rays; contact with horses, or living on a farm; pesticide treatment of the house during the child's lifetime; or exposure to burning incense. © 1994 Wiley‐Liss, Inc.
Significance of epidermal growth factor receptor expression in primary human endometrial cancer
Authors: Scambia Giovanni , Panici Pierluigi Benedetti , Ferrandina Gabriella , Battaglia Francesco , Distefano Mariagrazia , D'Andrea Giorgia , De Vincenzo Rosa , Maneschi Francesco , Ranelletti Franco Oreste , Mancuso Salvatore
Published: July 2010

Radioreceptorial assessment of EGFR expression was prospectively performed on 60 primary human endometrial tumors. Of these, 26 were EGFR‐positive while 13 expressed high EGFR levels. High EGFR levels correlated well with poor histopatho‐logical grading. No correlation with histopathological type, stage, myometrial invasion, lymph‐node involvement or steroid hormone receptor status was observed. Disease‐free survival rate was significantly shorter in the cases with high than in the cases with low EGFR levels. These results suggest a potential role of EGFR expression assessment in prognostic characterization of endometrial cancer patients. © 1994 Wiley‐Liss, Inc.
High prevalence of neutralizing activity to helicobacter pylori cytotoxin in serum of gastric‐carcinoma patients
Authors: Hirai Masamichi , Azuma Takeshi , Ito Shigeji , Kato Takuji , Kohli Yoshihiro , Fujiki Norio
Published: July 2010

Helicobacter pylori infection is causally related to chronic type‐B gastritis, and may also be associated with an increased risk of gastric carcinoma. Vacuolating cytotoxin, which is an 87‐kDa protein secreted by H. pylori, induces eukaryotic cell vacuolation in vitro. To determine whether there is an association between H. pylori vacuolating cytotoxin and gastric carcinoma, we investigated several characteristics of H. pylori infection, i.e., isolation of H. pylori from gastric biopsies, antibodies specific for H. pylori, detection of neutralizing activity to vacuolating cytotoxin in serum and immunological detection of cytotoxin by serum. Out of 6 sera from gastric‐carcinoma patients, all showed the neutralizing activity to vacuolating cytotoxin, in contrast to 3 of 5 sera from peptic‐ulcer patients. Normal individuals showed no neutralizing activity. All sera possessing the neutralizing activity recognized an 87‐kDa protein band by Western blot analysis. Our results confirmed that cytotoxin‐neutralizing activity in human sera was associated with immunodetection of an 87‐kDa protein. To further evaluate neutralizing activity in serum from gastric‐carcinoma patients, we retrospectively analyzed frozen‐stocked serum samples from 22 gastric‐carcinoma patients. Sera from 21 of these 22 patients exhibited neutralizing activity. These sera were also checked for antibodies to H. pylori, using an ELISA; 16 sera showed positive results. Our results indicate that detection of cytotoxin‐neutralizing activity in sera is strongly associated with H. pylori infection, and probably with gastric carcinoma, and is also of interest in the diagnosis of H. pylori infection. © 1994 Wiley‐Liss, Inc.
Preferential usage of T‐cell receptor αβ variable regions among tumor‐infiltrating lymphocytes in primary human malignant melanomas
Authors: Straten Per Thor , Schøller Jørgen , Hou‐Jensen Klaus , Zeuthen Jesper
Published: July 2010

The usage of T‐cell‐receptor (TCR) αβ variable (V) regions among tumor infiltrating lymphocytes (TILs) in primary human malignant melanomas was characterized using a method based on the polymerase chain reaction (PCR). A panel of 57 different variable‐region primers specific for the TCR Vα 1–29 and Vβ 1–28 was designed, and a semi‐quantitative PCR method applicable to formalin‐fixed, paraffin‐embedded tissues was developed. This semi‐quantitative method was demonstrated to be reproducible and to be useful for the assessment of Vα‐ and Vβ‐gene‐family usage in formalin‐fixed, paraffin‐embedded tissue samples. A total of 9 different histopathologically characterized primary tumors were analyzed in this study. The TILs in these tumors were found to preferentially express certain TCR Vα and Vβ regions. The differential usage of certain Vα regions was very pronounced as illustrated by Vα4, which was highly expressed in 3/8 tumors, and Vα22, which was highly expressed in 4/8 tumors. For comparison, specific highly expressed Vα regions in control samples of peripheral‐blood lymphocytes rarely exceded 10%. The most highly expressed VB region was Vβ8, which was highly expressed in 2/8 tumors. For the highly expressed Vα4 and Vα22 and Vβ8 regions, the high levels may be explained by the in situ clonal or oligoclonal expansion of TIL. In one specific case, the high expression of Vβ8 was due to expansion of a single clone of TILs, as evidenced by a fully readable sequence of the CDR3 (V‐D‐J) region, determined by direct sequencing of the PCR product corresponding to Vβ8. In contrast, sequence analysis of Vα22, which was expressed in the same tumor sample at similar levels, demonstrated the simultaneous presence of 3 different CDR3 (V‐J) sequences derived from Vα22 transcripts of exactly the same length. The observed preferential use of TCR Vα and Vβ regions suggests the in situ clonal expansion of specific populations of T‐cells, possibly reactive with melanoma‐associated peptides presented by HLA molecules. The preferential use of TCR Vα and Vβ regions may imply the involvement of a limited number of shared melanoma‐associated peptides. © 1994 Wiley‐Liss, Inc.
Altered homologous and heterologous gap‐junctional intercellular communication in primary human liver tumors associated with aberrant protein localization but not gene mutation of connexin 32
Authors: Krutovskikh V. , Mazzoleni G. , Mironov N. , Omori Y. , Aguelon A.‐M. , Mesnil M. , Berger F. , Partensky C. , Yamasaki H.
Published: July 2010

Gap‐junctional intercellular communication (GJIC) in 20 primary human liver tumors with different degrees of malignancy has been studied at the functional and molecular levels. When GJIC capacity was determined by dye‐transfer assay performed directly with freshly removed tumor tissue, significant reduction was found in all samples, regardless of their morphology. In addition, a selective lack of GJIC between tumor and surrounding non‐tumorous cells was observed in some cases, probably due to the physical separation between them resulting from encapsulation of tumors. There was, however, no essential change in the level of expression of the major liver gap‐junction protein, connexin (ex) 32, in liver tumors as measured by Northern and Western blot analyses. Immunohistochemical study revealed aberrant localization of ex 32 in the majority of malignant liver tumors. Instead of cytoplasmic membrane localization at intercellular contacts, ex 32 was detected mainly either intracytoplasmically or in plasma membrane free from contact with other cells. We did not detect any mutation in the coding sequence of the ex 32 gene from any of the human liver tumors we tested. Thus it is likely that the aberrant localization of ex 32 in tumor cells is due to disruption of the mechanisms for establishment of this protein into gap‐junction plaques, rather than to structural abnormality of the ex 32 protein itself. Another member of the connexin family, ex 43, not detectable in non‐tumorigenic hepatocytes, was expressed in several tumors, especially in invasive areas, but was detected in only a few tumor cells and was localized intracytoplasmically, suggesting that ex 43 protein is not involved in GJIC in the tumors. © 1994 Wiley‐Liss, Inc.
Nuclear DNA content, proliferating‐cell nuclear antigen (PCNA) and p53 immunostaining in predicting progression of laryngeal cancer in situ lesions
Authors: Munck‐Wikland Eva , Edström Staffan , Jungmark Eva , Kuylenstierna Richard , Lindholm Johan , Auer Gert
Published: July 2010

Squamous epithelial cancer in situ (CIS) of the upper aerodi‐gastric tract is a histopathologically well‐defined condition. However, in clinical practice, morphological grading of dysplasia is difficult and shows large variability. The biology of CIS remains enigmatic, and there is yet no reliable way to predict whether a CIS lesion will progress to invasive cancer, remain stable or regress. In the search for markers able to foretell clinical outcome, we performed image DNA cytometry (ICM) and immunohistochemical staining for PCNA as well as p53 in 38 laryngeal CIS lesions, of which 9 progressed to invasive cancer. The majority of the CIS lesions displayed high‐grade DNA aberration, a high PCNA‐positive rate, and every third lesion was p53‐poskive by immunostaining. The lesions which progressed to invasive cancer showed a clear tendency towards more pronounced DNA aberration, a higher percentage of intense PCNA staining and more frequent p53 positivity. By combining the results from the analyses of DNA, PCNA and p53 in a prognostic index for each individual case, we correctly classified 82% of the lesions as progressors or non‐progressors. © 1994 Wiley‐Liss, Inc.
Induction and promotion of forestomach tumors by sodium nitrite in combination with ascorbic acid or sodium ascorbate in rats with or without N‐metuyl‐N′‐nitro‐N‐nitrosoguanidine pre‐treatment
Authors: Yoshida Yasunori , Hirose Masao , Takaba Katsumi , Kimura Juki , Pito Nobuyuki
Published: July 2010

In experiment I, short‐term effects of combined treatment with anti‐oxidants, sodium ascorbate (NaAsA) and sodium nitrite (NaNO2) on forestomach cell proliferation were examined in F344 male rats. Groups of 5 animals aged 6 weeks were treated for 4 weeks with 0.8% catechol, 0.8% hydroquinone, 1% tert butyl‐hydroquinone (TBHQ), 2% gallic acid or 2% pyrogallor alone or in combination with 0.3% NaNO2 in the drinking water and/or I % NaAsA in the diet. The thicknesses of forestomach mucosa in rats treated with anti‐oxidants and NaNO2 in combination were greater than those with antioxidant alone and additional NaAsA treatment further enhanced the thickening of mucosa. It was noteworthy that values for mucosae of animals treated with NaNO2 and NaAsA without anti‐oxidant were similar to those for anti‐oxidants. In experiment 2, effects of combined treatment with NaAsA or ascorbic acid '(AsA) and NaNO2 on carcinogenesis were examined in F344 male rats with or without N‐methyl‐N' ‐nitro‐N‐nitrosogua‐nidine (MNNG) pre‐treatment. Groups of 20 or 15 rats, respectively, aged 6 weeks, were given a single intra‐gastric administration of I SO mg/kg body weight of MNNG in DMSOwater =1:1 or the vehicle alone by stomach tube. Starting I week later, they received supplements of I % NaAsA or I % AsA in the diet and 0.3% NaNOz in drinking water in combination, each of the individual chemicals alone, or basal diet until the end of week 52. In MNNG‐treated animals, incidences of forestomach papillomas and carcinomas were significantly enhanced in the NaNO2 alone group (84 and 47%, respectively) as compared with the basal diet group (30 and 10%), with further significant increase in carcinomas occurring with additional NaAsA (79%, p < 0.05) or AsA (85%, p < 0.05) treatment. In animals without MNNG, all animals in the NaNO2 group demonstrated mild hyperplasia, additional administration of NaAsA or AsA remarkably enhancing the grade of hyperplasia, and resulting in 53% and 20% incidences, respectively, of papillomas. Thus NaNO2 was demonstrated to exert promoter action for forestomach carcinogenesis, with NaAsA and AsA acting as co‐promoters. The results strongly indicate that combined treatment with NaAsA or AsA and NaNO2 may induce forestomach carcinomas in the long term. © 1994 WUey‐Liss, Inc.
Receptor‐mediated cyotoxicity of a‐MSH fragments containing melphalan in a human melanoma cell line
Authors: Morandini R. , Suli‐Vargha H. , Libert A. , Loir B. , Botyánszki J. , Medzihradszky K. , Ghanem G.
Published: July 2010

Four α‐MSH drug conjugates have been synthesized, 2 C‐terminal (Pep 3 and 4) and 2 central fragments (Pep I and 2), the latter being the 4–10 sequence known to be the main α‐MSH‐receptor‐recognition site. Melphalan was introduced into each sequence at different locations. Their ability to recognize α‐MSH receptors as well as their cytotoxic effects were compared in 3 cell lines: melanoma, carcinoma and fibroblast cells. Pep I and 2 were able to specifically bind to MSH receptors on melanoma cells by displacing labelled a‐MSH from its binding sites at concentrations similar to the 4–10 heptapeptide sequence known to contain the main receptor‐recognition site. They subsequently penetrate the cell, most probably by a receptor internalization mechanism, since about half of their effect could be inhibited by competition at the receptor level. Significant and selective cytotoxic effects to melanoma cells could be observed after only 2 hr exposure to the drug conjugates. Interestingly, these 2 conjugates, differing only in melphalan position, showed completely different cytotoxic/ in terms of IC50 values, Pep I being 24 times more toxic to all cells; but the 2 were equally specific to melanoma cells. However, they both were less toxic to all cells than melphalan itself. Furthermore, Pep I and 2 were able to block the receptor and, unlike Pep 3 and 4, their cytotoxic effect could be significantly inhibited by an α‐MSH agonist. Pep 3 and 4 were 5 to 10 times less toxic than melphalan to melanoma and carcinoma cells and 50 times less to fibroblast cells, and did not show any cell‐type selectivity. They were less toxic than Pep I to melanoma and carcinoma cells by a factor of 2, but equally toxic to fibroblasts. In contrast, they were more toxic than Pep 2 to fibroblasts, melanoma and carcinoma by a factor of 3, 10 and 24 respectively. Our data strongly suggest a receptor‐mediated cytotoxicity mechanism occurring with a‐MSH central fragments in human melanoma cells due to the presence of α‐MSH‐specific receptors. This mechanism appeared to be both peptide‐ and cell‐type‐specific.
Unusually marked hypoxic sensitization to indoloquinone E09 and mitomycin C in a human colon‐tumour cell line that lacks DT‐diaphorase activity
Authors: Plumb Jane A. , Workman Paul
Published: July 2010

Studies with purified DT‐diaphorase have shown that the enzyme is capable of catalyzing a two‐electron reduction of the novel indoloquinone E09 to a DNA‐damaging alkylating species. The aim of this study was to determine to what extent DT‐diaphorase may be involved in the metabolic activation of E09 and mitomycin C in both aerobic and hypoxic conditions. Two human colon‐carcinoma cell lines were used; HT29 has high levels of DT‐diaphorase whilst BE lacks this activity because of a point mutation in the NQOI gene. In aerobic conditions the 2 cell lines show similar sensitivities to a number of cytotoxic drugs including cisplatin, doxorubicin and etopo‐side. They are equally sensitive to the benzotriazine di‐N‐oxide SR 4233 but HT29 is more sensitive than BE to mitomycin C and E09. Sensitivity to SR 4233 is increased by about 100‐fold for both cell lines in hypoxic conditions. DT‐diaphorase‐deficient BE cells show markedly increased sensitivity to mitomycin C and particularly E09 in hypoxic conditions, whereas DT‐diaphorase‐rich HT29 cells show little hypoxic sensitization to these agents unless exposed in the presence of dicoumarol. These results suggest that DT‐diaphorase can reduce E09 and mitomycin C to potent cytotoxic species in aerobic conditions, and this activity predominates over the one‐electron‐reducing enzymes even in hypoxic conditions. In the absence of DT‐diaphorase activity, E09 and mitomycin C are reduced in hypoxic conditions, presumably by one‐electron‐reducing enzymes, to a similar or greater extent than is achieved with DT‐diaphorase.
Aryl hydrocarbon hydroxylase activity in chemically induced and toremifene‐treated mammary tumors in rats
Authors: Pyykkö Kaija , Ala‐Uotila Sari , Jaakkola Ulla‐Marjut , Lähde Matti
Published: July 2010

Aryl hydrocarbon hydroxylase (AHH) and NADPH‐cyto‐chrome P450 reductase (NCR) activity of microsomes from liver, lungs, uterus and mammary tumors in dimethylbenz‐antrachene‐induced and torem'rfene‐treated female Sprague‐Dawley rats were studied. AHH and NCR activity in tumors and uteri was low compared with that in livers and lungs. The distribution of AHH in tumors was wide and skewed. It varied in different tumors of the same animal as widely as between different animals. The enzyme activity in tumors did not correlate with that in the liver, lungs or uterus of the same animal. Toremifene had no effect on AHH or NCR in tumor or liver, but it decreased them in lungs. Tumor AHH activity correlated with its overall growth rate and development stage. The results suggest that malignant transformation leading to the defect in growth regulation also confuses the complex regulatory system of AHH activity.
Carcinogenicity of 4‐methoxyphenol and 4‐methylcatechol in F344 rats
Authors: Asakawa Emiko , Hirose Masao , Hagiwara Akihiro , Takahashi Satoru , Ito Nobuyuki
Published: July 2010

The carcinogenic potentials of 4‐methoxyphenol (4‐MP) and 4‐methylcatechol (4‐MC), phenolic compounds which are structurally similar to the known forestomach carcinogen BHA and the glandular stomach carcinogen catechol respectively, and cause considerably enhanced cell proliferation and cytotoxicities in rat forestomach and/or glandular stomach epithelium, were examined in male and female F344 rats. Groups of 30 male and female animals were administered diets containing 2% 4‐MP or 2% 4‐MC for 104 weeks. Histopathological findings in the 4‐MP case included atypical hyperplasias (male, 67%, female, 37%), papillomas (50%, 23%) and squamous‐cell carcinomas (77%, 20%) in the forestomach. 4‐MC induced forestomach papillomas (70%, 93%) and squamous‐cell carcinomas (53%, 37%), also glandular stomach submucosal hyperplasias (90%, 93%), adenomas (100%, 100%) and adenocarcinomas (57%, 47%), with ulceration or erosion. The degree of differentiation of the squamous‐cell carcinomas induced by 4‐MP was less than with 4‐MC. The present study demonstrated unequivocal forestomach carcinogenicity for 4‐MP and forestomach and glandular stomach carcinogenicity for 4‐MC, with cytotoxicity and cell proliferation both appearing as important factors for these non‐genotoxic carcinogens.
A novel composite construct increases the vascularization potential of PEG hydrogels through the incorporation of large fibrin ribbons
Authors: Mason Mariah N. , Mahoney Melissa J.
Published: July 2010

Developing a mechanism to vascularize tissue‐engineered constructs is imperative for transplant function and integration, particularly when delivering hypoxia‐sensitive tissues, such as pancreatic islets. Previous efforts have focused on bulk modifications of scaffold materials rendering the entire construct permissive to vessel penetration or the formation of a porous structure where vessels can infiltrate the empty spaces. Here, we describe a novel construct composed of large fibrin ribbons encapsulated within a poly(ethylene glycol) (PEG) hydrogel. The PEG/fibrin ribbon composite scaffold facilitates coculture of adhesive and nonadhesive cell types, thus providing closely neighboring environments with distinct material properties specific to the needs of two clinically relevant cell populations. This advantage is demonstrated here by the successful coculture of pancreatic islets in the PEG component and vessel‐forming endothelial cells in entrapped fibrin ribbons. Transplanted endothelial cells can form anastomosies with host vasculature, suggesting that our cocultures may lead to more rapid scaffold vascularization. Additionally, we show that surface‐seeded endothelial cells form multicellular projections that migrate into nonadhesive PEG hydrogels along permissive fibrin ribbons, further demonstrating composite construct vascularization potential. Distribution of large fibrin ribbons throughout PEG hydrogels provide a potential mechanism for vascularization of a well‐established biomaterial without inherently changing its desirable properties. © 2010 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2010.
Controlled induction of distributed microdeformation in wounded tissue via a microchamber array dressing
Authors: Kane Bartholomew J. , Younan George , Helm Douglas , Dastouri Pouya , Prentice‐Mott Harrison , Irimia Daniel , Chan Rodney K. , Toner Mehmet , Orgill Dennis P.
Published: July 2010

Mechanical stimuli are known to play an important role in determining the structure and function of living cells and tissues. Recent studies have highlighted the role of mechanical signals in mammalian dermal wound healing. However, the biological link between mechanical stimulation of wounded tissue and the subsequent cellular response has not been fully determined. The capacity for researchers to study this link is partially limited by the lack of instrumentation capable of applying controlled mechanical stimuli to wounded tissue. The studies outlined here tested the hypothesis that it was possible to control the magnitude of induced wound tissue deformation using a microfabricated dressing composed of an array of open‐faced, hexagonally shaped microchambers rendered in a patch of silicone rubber. By connecting the dressing to a single vacuum source, the underlying wounded tissue was drawn up into each of the microchambers, thereby inducing tissue deformation. For these studies, the dressings were applied to full‐thickness murine dermal wounds with 200 mmHg vacuum for 12 h. These studies demonstrated that the dressing was capable of inducing wound tissue deformation with values ranging from 11 to 29%. Through statistical analysis, the magnitude of the induced deformation was shown to be a function of both microchamber height and width. These results demonstrated that the dressing was capable of controlling the amount of deformation imparted in the underlying tissue. By allowing the application of mechanical stimulation with varying intensities, such a dressing will enable the performance of sophisticated mechanobiology studies in dermal wound healing. © 2010 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2010.
Calcium supplementation and the risks of atherosclerotic vascular disease in older women: Results of a 5-year RCT and a 4.5-year follow-up
Authors: Lewis Joshua R , Calver Janine , Zhu Kun , Flicker Leon , Prince Richard L
Published: July 2010

Concern has been expressed that calcium supplementation, a key intervention for preventing osteoporotic fracture in older women, may increase the risk of atherosclerotic vascular disease. To evaluate the risk further, an examination of complete verified atherosclerotic vascular hospitalization and mortality data from a 5-year randomized, controlled trial (RCT) of calcium carbonate and 4.5 years of posttrial follow-up was undertaken. This study used data from a published 5-year randomized, double-blinded, placebo-controlled trial [Calcium Intake Fracture Outcome Study (CAIFOS)]. The participants were 1460 women aged 75.1 ± 2.7 years at baseline (1998) recruited from the general population and randomized to receive 1200 mg of calcium carbonate daily or an identical placebo. All hospital admission and deaths during the 5-year study and the 4.5-year follow-up were derived from the Western Australian Data Linkage Service (WADLS). Hazard ratios (HRs) for the combined endpoint of atherosclerotic vascular mortality or first hospitalization were calculated using prespecified intention-to-treat and per-protocol models. The intervention group that received calcium supplementation did not have a higher risk of death or first-time hospitalization from atherosclerotic vascular disease in either the 5-year RCT [multivariate-adjusted HR = 0.938, 95% confidence interval (CI) 0.690–1.275] or during the 9.5 years of observational study (multivariate-adjusted HR = 0.919, 95% CI 0.737–1.146). Further analysis suggested that calcium supplementation may reduce the risk of hospitalization and mortality in patients with preexisting atherosclerotic cardiovascular disease. This trial provides compelling evidence that calcium supplementation of 1200 mg daily does not significantly increase the risk of atherosclerotic vascular disease in elderly women. © 2011 American Society for Bone and Mineral Research.
Impact of race on hyperparathyroidism, mineral disarrays, administered vitamin D mimetic, and survival in hemodialysis patients
Authors: Kalantar-Zadeh Kamyar , Miller Jessica E , Kovesdy Csaba P , Mehrotra Rajnish , Lukowsky Lilia R , Streja Elani , Ricks Joni , Jing Jennie , Nissenson Allen R , Greenland Sander , Norris Keith C
Published: July 2010

Blacks have high rates of chronic kidney disease, are overrepresented among the US dialysis patients, have higher parathyroid hormone levels, but greater survival compared to nonblacks. We hypothesized that mineral and bone disorders (MBDs) have a bearing on survival advantages of black hemodialysis patients. In 139,328 thrice-weekly treated hemodialysis patients, including 32% blacks, in a large dialysis organization, where most laboratory values were measured monthly for up to 60 months (July 2001 to June 2006), we examined differences across races in measures of MBDs and survival predictabilities of these markers and administered the active vitamin D medication paricalcitol. Across each age increment, blacks had higher serum calcium and parathyroid hormone (PTH) levels and almost the same serum phosphorus and alkaline phosphatase levels and were more likely to receive injectable active vitamin D in the dialysis clinic, mostly paricalcitol, at higher doses than nonblacks. Racial differences existed in mortality predictabilities of different ranges of serum calcium, phosphorus, and PTH but not alkaline phosphatase. Blacks who received the highest dose of paricalcitol (>10 µg/week) had a demonstrable survival advantage over nonblacks (case-mix-adjusted death hazard ratio = 0.87, 95% confidence level 0.83–0.91) compared with those who received lower doses (<10 µg/week) or no active vitamin D. Hence, in black hemodialysis patients, hyperparathyroidism and hypercalcemia are more prevalent than in nonblacks, whereas hyperphosphatemia or hyperphosphatasemia are not. Survival advantages of blacks appear restricted to those receiving higher doses of active vitamin D. Examining the effect of MBD modulation on racial survival disparities of hemodialysis patients is warranted. © 2010 American Society for Bone and Mineral Research.
Co‐chaperone BAG3 and adenovirus penton base protein partnership
Authors: Gout E. , Gutkowska M. , Takayama S. , Reed J.C. , Chroboczek J.
Published: July 2010

The BAG family of Hsp70/Hsc70 co‐chaperones is characterised by the presence of a conserved BAG domain at the carboxyl‐terminus. BAG3 protein is the only member of this family containing also the N‐terminally located WW domain. We describe here the identification of adenovirus (Ad) penton base protein as the first BAG3 partner recognising BAG3 WW domain. Ad penton base is the viral capsid constituent responsible for virus internalisation. It contains in the N‐terminal part two conserved PPxY motifs, known ligands of WW domains. In cells producing Ad penton base protein, cytoplasmic endogenous BAG3 interacts with it and co‐migrates to the nucleus. Preincubation of BAG3 with Ad base protein results in only slight modulation of BAG3 co‐chaperone activity, suggesting that this interaction is not related to the classical BAG3 co‐chaperone function. However, depletion of BAG3 impairs the cell entry of the virus and viral progeny production in Ad‐infected cells, suggesting that the interaction between virus penton base protein and cellular co‐chaperone BAG3 positively influences virus life cycle. These results thus demonstrate a novel host–pathogen interaction, which contributes to the successful infectious life cycle of adenoviruses. In addition, these data enrich our knowledge about the multifunctionality of the BAG3 co‐chaperone. J. Cell. Biochem. 111: 699–708, 2010. © 2010 Wiley‐Liss, Inc.
AKT1 leader gene and downstream targets are involved in a rat model of kidney allograft tolerance
Authors: Jovanovic Vojislav , Giacomelli Luca , Sivozhelezov Victor , Degauque Nicolas , Lair David , Soulillou Jean‐Paul , Pechkova Eugenia , Nicolini Claudio , Brouard Sophie
Published: July 2010

Tolerance is the so‐called “Holy Grail” of transplantation but achieving this state is proving a major challenge, particularly in the clinical settings. This tolerance state can be induced in rodent models using a variety of maneuvers. This phenomenon is classically characterized by donor specificity (recipients accept a secondary donor‐specific allograft but reject third‐party allograft) as well as by the absence of chronic rejection lesion. We previously showed that administration and anti‐donor anti‐class II serum on the day of transplantation induce tolerance to a kidney allograft in the LEW‐1W to LEW‐1A strain combination. In this study, we used DNA microarrays to compare gene patterns involved in anti‐donor anti‐class II tolerated or untreated syngeneic kidney transplants in this strain combination. Statistical and non‐statistical analyses were combined with ab initio analysis, using the recently developed leader gene approach, to shed new light on this phenomenon. Theoretical and experimental results suggest that tolerance and rejection outcome may be in large part determined by low expression variations of some genes, which can form a core gene network around specific genes such as Rac1, NFKB1, RelA, AKT1, IKBKB, BCL2, BCLX, and CHUK. Through this model, we showed that AKT1 gene, WNT pathway and NO synthesis are strictly connected to each other and may play an important role in kidney tolerance and rejection processes, with AKT1 gene being the center of this complex network of interactions. J. Cell. Biochem. 111: 709–719, 2010. © 2010 Wiley‐Liss, Inc.
Homology modeling and molecular dynamics simulation studies of human type 1 3β‐hydroxysteroid dehydrogenase: Toward the understanding of cofactor specificity
Authors: Zhao Yongbing , Xiao Jingfa
Published: July 2010

The human type 1 isoform of 3β‐hydroxysteroid dehydrogenase is a member of short‐chain oxidoreductase family that catalyzes the conversion of dehydroepiandrosterone to androstenedione. To compare the molecular events underlying cofactor specificity in the wild‐type and D35A/K36R mutant enzymes, molecular dynamics (MD) simulations of fully solvated cofactor‐3β‐HSD1 (wild‐type and mutant) complex are performed. Molecular modeling methods are applied to construct three‐dimensional models of cofactor‐3β‐HSD1 complexes based on Uridine diphosphate (UDP)‐galactose 4‐epimerase crystal structure from Escherichia coli. The binding mode and binding energy analysis between four different complexes indicate that Asp35 and Lys36 are key residues for the cofactor specificity of 3β‐HSD1, which is in agreement with mutagenesis studies results obtained by Thomas et al.8 The MD results also display that the residue Glu41 may be another important residue except Asp35 and Lys36 for the cofactor specificity and that this result needs further mutational experiment for validation. © 2010 Wiley Periodicals, Inc. J Comput Chem, 2010
Parallel implementation of γ‐point pseudopotential plane‐wave DFT with exact exchange
Authors: Bylaska Eric J. , Tsemekhman Kiril , Baden Scott B. , Weare John H. , Jonsson Hannes
Published: July 2010

Semi‐local functionals commonly used in density functional theory (DFT) studies of solids usually fail to reproduce localized states such as trapped holes, polarons, excitons, and solitons. This failure is ascribed to self‐interaction which creates a Coulomb barrier to localization. Pragmatic approaches in which the exchange correlation functionals are augmented with small amount of exact exchange (hybrid‐DFT, e.g., B3LYP and PBE0) have shown to promise in rectifying this type of failure, as well as producing more accurate band gaps and reaction barriers. The evaluation of exact exchange is challenging for large, solid state systems with periodic boundary conditions, especially when plane‐wave basis sets are used. We have developed parallel algorithms for implementing exact exchange into pseudopotential plane‐wave DFT program and we have implemented them in the NWChem program package. The technique developed can readily be employed in Γ‐point plane‐wave DFT programs. Furthermore, atomic forces and stresses are straightforward to implement, making it applicable to both confined and extended systems, as well as to Car‐Parrinello ab initio molecular dynamic simulations. This method has been applied to several systems for which conventional DFT methods do not work well, including calculations for band gaps in oxides and the electronic structure of a charge trapped state in the Fe(II) containing mica, annite. © 2010 Wiley Periodicals, Inc. J Comput Chem, 2010
Gabedit—A graphical user interface for computational chemistry softwares
Authors: Allouche Abdul‐Rahman
Published: July 2010

Gabedit is a freeware graphical user interface, offering preprocessing and postprocessing adapted (to date) to nine computational chemistry software packages. It includes tools for editing, displaying, analyzing, converting, and animating molecular systems. A conformational search tool is implemented using a molecular mechanics or a semiempirical potential. Input files can be generated for the computational chemistry software supported by Gabedit. Some molecular properties of interest are processed directly from the output of the computational chemistry programs; others are calculated by Gabedit before display. Molecular orbitals, electron density, electrostatic potential, nuclear magnetic resonance shielding density, and any other volumetric data properties can be displayed. It can display electronic circular dichroism, UV–visible, infrared, and Raman‐computed spectra after a convolution. Gabedit can generate a Povray file for geometry, surfaces, contours, and color‐coded planes. Output can be exported to a selection of popular image and vector graphics file formats; the program can also generate a series of pictures for animation. Quantum mechanical electrostatic potentials can be calculated using the partial charges on atoms, or by solving the Poisson equation using the multigrid method. The atoms in molecule charges can also be calculated. Gabedit is platform independent. The code is distributed under free open source X11 style license and is available at http://gabedit.sourceforge.net/. © 2010 Wiley Periodicals, Inc. J Comput Chem, 2010
Lysophosphatidylcholine‐mediated functional inactivation of syndecan‐4 results in decreased adhesion and motility of dendritic cells
Authors: Bühligen Johannes , Himmel Mirko , Gebhardt Carl , Simon Jan C. , Ziegler Wolfgang , Averbeck Marco
Published: July 2010

Following antigen contact, maturation and migration of DCs into lymphatic tissues are crucial to the developing immune response or maintenance of tolerance. Lysophosphatidylcholine (LysoPC) is generated during apoptosis of cells and acts as a “find‐and‐eat‐me” signal thought to prevent autoimmunity. Moreover, LysoPC can activate PKCδ and initiates a signaling cascade that leads to phosphorylation and inactivation of syndecan‐4 (SDC4), a heparansulfate proteoglycan integrin co‐receptor. In human monocyte‐derived DCs, we recently demonstrated that SDC4 is upregulated during maturation thereby stimulating DC motility. Here, we investigate the effects of LysoPC on DC motility as well as on the involvement of PKCδ phosphorylation‐dependent regulation of DC motility by SDC4 and PKCα. Employing a static adhesion assay and videomicroscopy, we show that LysoPC inhibits adhesion of DCs to fibronectin and motility of DCs by decreasing podosome formation. Moreover, DC podosome formation and motility, which both are regulated by SDC4 and subject to control by PKCδ‐dependent phosphorylation of SDC4, were inhibited in LysoPC‐matured DCs. Thus, these DC are defective in adhesion and migration. Based on our results, we hypothesize that LysoPC released during apoptosis might delay DC migration to lymphoid organs and thus prevent autoimmunity. J. Cell. Physiol. 225: 905–914, 2010. © 2010 Wiley‐Liss, Inc.