bluuebunny/crossref_metadata_2025 huggingface dataset:
HMFG1 antigen: A new marker for carcinomatous meningitis
Authors: Moseley R. P. , Oge K. , Shafqat S. , Moseley C. M. , Sullivan N. M. , Badley R. A. , Burchell J. , Taylor‐Papadimitriou J. , Coakham H. B.
Published: February 2007

Carcinomatous meningitis is a devastating metastatic complication of systemic carcinoma, which may occur insidiously, accompanied by a confusing spectrum of clinical symptoms and signs. In the absence of reliable diagnostic tumour markers, the diagnosis is established by the demonstration of malignant cells within the cerebrospinal fluid (CSF). Cytological techniques requiring skillful interpretation are occasionally negative in the presence of established disease, and when positive may indicate leptomeningeal malignancy of such advanced nature that effective palliation is difficult. Biochemical tumour marker technology offers the potential of reliable diagnosis in early disease states, prior to the appearance of exfoliated malignant cells. In a series of 100 patients, we assayed for an epithelial associated glycoprotein (HMFGI antigen) in CSF obtained at lumbar puncture. In 18 of 20 patients with carcinomatous meningitis, this high‐molecular‐weight glycoprotein was detectable in the CSF. The antigen was also present in 2 patients with neoplastic meningitis complicating lymphoma and medulloblastoma, but was not detected in the CSF of the remaining 78 patients.
Early and late stages of foreign‐body carcinogenesis can be induced by implants of different shapes
Authors: Moizhess T. G. , Vasiliev J. M.
Published: February 2007

Implanted foreign bodies of certain shapes, especially large non‐perforated polymer films, induce subcutaneous sarcomas in a high percentage of mice and rats; in contrast, implants of other shapes, e.g., perforated or minced films or Millipore filters with 0.45 μm pores, are non‐carcinogenic or only weakly carcinogenic. Experiments described in this report have shown that when carcinogenic non‐perforated film was removed at 3.5 months after implantation and one of the “non‐carcinogenic” foreign bodies listed above was implanted into the same subcutaneous sites, a high percentage of sarcomas was induced. The same non‐carcinogenic or weakly carcinogenic foreign bodies implanted in the mice after total body γ irradiation or after single injection of ethylnitrosourea induced subcutaneous sarcomas in significantly higher percentages of animals than the same foreign bodies implanted in control mice. Our data suggest that foreign bodies of “non‐carcinogenic” or “weakly carcinogenic” shapes can act as efficient promoters of subcutaneous carcinogenesis initiated by other agents such as implanted “carcinogenic” foreign bodies, ionizing radiation or chemical carcinogen.
Antigen common to several species, recognized by a rat monoclonal antibody raised against syngeneic rat bladder tumor
Authors: Eto Hiroshi , Saya Hideyuki , Nakata Motomi , Mizoguchi Akira , Kamidono Sadao
Published: February 2007

A rat monoclonal antibody (MAb) termed RS‐11 (Ig M) was obtained by syngeneic immunization with rat bladder tumor cells induced by N‐butyl, N‐hydroxybutylnitrosamine (BBN). immunocytochemical analysis showed that RS‐11 is also reactive with mouse, dog and human bladder tumor‐cell lines and some other human tumor‐cell lines but not myeloma or leukemia cells. Immunohistochemical examination of paraffin‐embedded tissues has shown that RS‐11 is reactive with mouse, rat, dog and human bladder tumors (5/5, 5/5, 1/1, 31/ 49) and some other tumors, but not with normal human uro‐thelium or normal rat tissues. The antigen is expressed on the majority of low‐grade or well‐differentiated tumors, but less on advanced, invasive tumors. The immunofluorescence staining pattern of cultured cells was cytoplasmic and filamentous. Immunoblotting revealed that the antigen is a Mr54,000 to Mr 56,000 protein which was extracted with difficulty from the cultured cells with Triton X‐100. The antigen was also detected in the culture supernatant by means of ELISA. Our results suggest that the epitope is expressed on cytoskeletons common to a wide variety of mammalian cells at a certain stage of differentiation.
Stability of phenotypic and genotypic traits during the establishment of a human neuroblastoma cell line, IGR‐N‐835
Authors: Bettan‐Renaud Laurence , Bayle Chantal , Teyssier Jean‐Raymond , Benard Jean
Published: February 2007

A prerequisite for the study of biological characteristics in neuroblastoma is the establishment of cell lines from tumors of patients. For our study a neuroblastoma cell line, IGR‐N‐835, was established from a primary tumor. During in vitro establishment of this line morphological changes were observed. IGR‐N‐835 exhibited both anchored cells and floating clusters. When cultured on bovine endothelial corneal cellular matrix, all tumor cells anchored to the matrix and proliferated, giving a continuous cell line. IGR‐N‐835 was studied in vitro and in vivo. Treatment with retinoic acid resulted in cell growth arrest and morphological differentiation. IGR‐N‐835 was highly tumorigenic in nude mice, exhibited a doubling time of 65 hr and was able to form colonies in methyl‐cellulose with a cloning efficiency of 0.46%. Immunocyto‐chemical studies showed reactivity of this line and its primary passages with CE7 monoclonal antibody (MAb). Cytogenetic analyses revealed stable mode and markers resulting from structural changes in chromosomes 10, 11 and 21 with no homogeneously staining regions or double minute chromosomes. Genomic amplification and overexpression of the N‐myc oncogene exhibited by the patient's tumor remained unchanged in nude mouse xenografts and the IGR‐N‐835 cell line. These phenotypic and genotypic traits were unchanged during establishment of this neuroblastoma line. IGR‐N‐835 could therefore constitute a suitable material for the study of the biology or therapeutics of human neuroblastoma.
Transplantable Marek's disease lymphomas. III. Induction of MHC‐restricted tumor immunity by lymphoblastoid cells in F1 hosts
Authors: Difronzo Nancy L. , Schierman Louis W.
Published: February 2007

F1 chickens, which were a cross between birds of the related inbred lines G‐BI and G‐B2, were immunized with in vitro cultured virus‐non‐producer lymphoblastoid cells that were either syngeneic or allogeneic with the challenge tumor cells. The lymphoblastoid cells were derived from Marek's disease herpesvirus (MDV)‐induced transplantable tumors. Previous findings showed that such immunization of G‐BI and G‐B2 chickens prevented early mortality caused by the tumors. Lymphoblastoid cells syngeneic with the tumors were more effective than allogeneic cells, suggesting that an MHC‐restricted immune response was induced, or, alternatively, that immune elimination of allogeneic cells prevented them from initiating strong immunity to MDV‐associated tumor antigens. Immune elimination of the immunizing cells should not occur in F1 birds heterozygous for the 2 different parental MHC haplotypes (B6 and B13). Early mortality among F1chickens immunized with lymphoblastoid cells that were syngeneic with the challenge tumor cells was significantly lower than for non‐immunized control chickens or for birds immunized with lymphoblastoid cells that were allogeneic with the challenge tumor cells. Our results suggest that MDV‐induced tumor antigens may be recognized by the host as altered‐self MHC antigens.
Influence of interferon on adriamycin uptake of cultured tumor cells
Authors: Yoneda Kazunori , Yamamoto Tetsuya , Osaki Tokio
Published: February 2007

Effect of human interferon β (IFNβ) or interferon γ (IFNγ) on cellular uptake of adriamycin (ADM) was measured in 3 in vitro‐cultured human tumor cell lines. Pre‐incubation of tumor cells with 100 lU/ml of IFNβ or γ for 6 hr resulted in an increased intracellular ADM concentration, but ADM efflux was not affected by the IFNs. The increase in cellular uptake of ADM was in agreement with both DNA and protein synthesis inhibition. 3H thymidine (3H‐TdR) incorporation was remarkably inhibited by ADM with pre‐treatment of 100 IU/ ml of each IFN, and an additive effect of ADM and IFN on cell growth inhibition could be observed. Similar additive inhibition against tumor‐cell proliferation in nude mice, which received combined treatment (twice/week) of IFNγ (5,000 IU/ mouse) and ADM (5‐20 μg/mouse), was also observed. These results indicate that IFN increases cellular influx of ADM, and antiproliferative activity against tumor cells is enhanced by a combination of IFN and ADM.
Overcoming effect of antibody against rat alpha‐fetoprotein (AFP) on the growth of daunorubicin‐resistant mutant rat ascites hepatoma cell line AH66
Authors: Ohkawa Kiyoshi , Tsukada Yutaka , Abe Toshio , Takada Koji , Hibi Nozomu
Published: February 2007

A daunorubicin (DNR)‐resistant variant (AH66DR) of al‐pha‐fetoprotein (AFP)‐producing rat ascites hepatoma AH66 was established. AH66DR was 169 times more resistant to DNR than AH66. A growth‐inhibitory effect due to the decrease in sugar uptake following treatment of the cell lines with specific antibody against highly purified rat AFP was also observed. Pre‐incubation of both lines with antibody prior to the measurement of 2‐deoxy‐D‐glucose (2dG) uptake resulted in a 45‐55% decrease in 2dG uptake compared to control cells with a 2‐fold reduction of Vmax value while the Km remained unchanged. Upon pre‐incubating AH66DR with antibody, an increased intracellular level of DNR concentration with reduction of efflux rate was observed. A significantly superior cytotoxic effect against AH66DR, which reached almost the same level as the cytotoxic effect of DNR against AH66, was found, as compared to various other controls when tumor cells were cultured with a mixture of antibody and DNR. Our in vitro results suggest that the DNR‐resistance of the AFP‐producing tumor cells may be overcome if the cells are treated with specific antibody.
Oestrogen potentiates topoisomerase‐II‐mediated cytotoxicity in an activated subpopulation of human breast cancer cells: Implications for cytotoxic drug resistance in solid tumours
Authors: Epstein R. J. , Smith P. J. , Watson J. V. , Waters C. , Bleehen N. M.
Published: February 2007

Primary resistance to chemotherapeutic agents is a major problem in the management of advanced cancer. By using oestrogen to modulate the topoisomerase II content of T‐47D human breast cancer cells, we show here that cell subpopu‐lations resistant to the topoisomerase‐ll‐interactive drug VP16 (etoposide) can be identified and quantified using single‐cell analytical techniques. Immunohistochemical studies reveal topoisomerase II to be present in approximately 10% of control cells compared with 30% of oestrogen‐stimulated cells, and this difference is reflected in the proportions of cells exhibiting VP16‐induced cell‐cycle delay. This moderate increase in overall cell sensitivity is accompanied by massive enhancement of clonogenic cell kill, suggesting that oestrogen enhances VP16 cytotoxicity by recruiting a clonogenic cell subpopulation characterized by increased topoisomerase II content. Flow cytometry confirms that the increase in topoisomerase II is localized to an activated G1‐phase cell subset. We conclude that (i) single‐cell analysis of cellular topoisomerase II content is predictive of VP16 chemosensitivity; (ii) the existence of resistant tumour‐cell subpopulations does not necessarily indicate the presence of phenotypically divergent subclones; and (iii) rational strategies for eliminating tumour resistance may be based on biological manipulation of specific cytotoxic drug targets.
Site‐associated expression of endogenous tumor lectins
Authors: Glaves Dorothy , Gabius Hans‐Joachim , Weiss Leonard
Published: February 2007

The expression of endogenous lectins was compared in mouse Lewis lung carcinomas growing in the kidney or sub‐cutaneously. A panel of carbohydrates coupled to a biotiny‐lated carrier molecule (bovine serum albumin), biotinylated desialylated glycoproteins and sulfated polysaccharides were used in histochemical assays to detect the presence and distribution of carbohydrate receptors. Heterogeneous staining patterns were observed with most carbohydrates in sections of tumor tissue from both anatomic sites, and staining intensities also varied within each section. At least 2 populations of cells were identified at each site, of which one had receptors for all carbohydrates, while the other had no receptors for melibiose, sialic acid, or α‐glucosides (maltose and glucose). There were quantitative differences in expression of endogenous lectins by tumors growing s.c. or in the kidney; 3LL cells growing in the kidney bound 6 out of 10 carbohydrates to a greater extent than 3LL cells in s.c. tumors. Conversely, 3LL cells in s.c. tumors bound heparin and asialofetuin to greater extents than cancer cells in kidney tumors. Biochemical analyses of detergent extracts of tissues subjected to affinity chromatography and subsequent SDS‐PAGE revealed quantitative and also qualitative differences in lectins between tumors growing in the 2 anatomic sites.
Detection by in situ hybridization of messenger RNAs of collagen types I and IV in murine mammary cancer
Authors: Clavel Christine , Doco Martine , Lallemand Aude , Laurent Maryvonne , Birembaut Philippe
Published: February 2007

Ten breast carcinomas developing in C3H/Bi female mice were studied by an in situ hybridization technique using cDNA probes encoding α‐I chains of collagens of types I and IV. The results obtained are compared to histochemical data on antibodies to collagens of types I and IV and ultrastructural observations on these tumors. Immunohistochemistry has revealed the presence of type‐IV collagen in basement membranes lining intraductal and well‐differentiated cancer nests. Type‐I collagen was detected in the stroma surrounding these cells. There was no cellular labelling when these antisera were used. In situ hybridization has shown that type‐IV collagen mRNA is detected in non‐invasive intraductal and welldifferentiated tumor cells and in endothelial cells in the stroma. Good correlation between detection of type‐IV collagen lining these cells and evidence of mRNA by in situ hybridization was thus observed. Invasive cancer cells did not express hybridization grains with the type‐IV collagen probe. Type‐I collagen mRNA was visualized in stromal cells, probably fibroblasts and myofibroblasts as shown by electron microscopy. The most active cells were localized close to noninvasive areas. Our data indicate persistent in‐vivo biosynthesis of type‐IV collagen by some cancer cells that produce their own limitative environment; they suggest that type‐IV collagen is not produced by invasive tumor cells and that stromal cells lining the non‐invasive regions have a peculiar behavior.
Replication of latent Epstein‐Barr virus genomes in normal and malignant lymphoid cells
Authors: Adams Alice , Pozos Tamara C. , Purvey Helen V.
Published: February 2007

DNA replication of 2 human lymphoid cell lines (U296 and Raji), latently infected with the Epstein‐Barr virus, has been compared using a density transfer approach. Typical of nonmalignant lymphoblastoid cells, U296 cells divided once in brornodeoxyuridine‐supplemented medium to form hybrid but not heavy‐density host DNA. Replication of the intracellular Epstein‐Barr virus DNA was selectively inhibited in these ceils with only 15% of the viral genomes duplicating once to form hybrid‐density viral DNA. However, some heavy‐density viral DNA was formed in the U296 cells and DNA synthesis can thus initiate again on newly duplicated viral genomes in cells that have traversed only a single S phase. These results contrast strongly with observations concerning the Burkitt‐lymphoma‐derived cell line. Lymphoma cells are not growth‐inhibited and most of the latent Epstein‐Barr virus genomes of the Raji line replicated once, and only once, in successive S phases. While the majority of the 50 Epstein‐Barr virus genomes of both the Raji and U296 cell lines are maintained as extra‐chromosomal DNA plasmids, the control of their duplication is distinctly different in the respective malignant and non‐malignant host cells.
Cytogenetic abnormalities in human ependymomas
Authors: Stratton M. R. , Darling J. , Lantos P. L. , Cooper C. S. , Reeves B. R.
Published: February 2007

The karyotypes of 4 human ependymomas have been determined. In one ependymoma, translocations involving chromosomes 9, 17 and 22 were observed together with the loss of the normal chromosome 17. A second ependymoma had many chromosomal alterations that included a translocation between chromosomes 1 and 2 and re‐arrangements involving chromosome 17. No major consistent alterations were detected in the remaining 2 cases. Our karyotypes do not resemble the few previously published karyotypes of ependymomas, but had features, such as the alterations involving chromosome 17, that were similar to those of other brain tumours in children.
Functional interactions of IL2 and TNF in the differentiation of LGL into lak effectors
Authors: Blay Jean Yves , Bertoglio Jacques , Fradelizi Didier , Chouaib Salem
Published: February 2007

We have previously reported on the synergistic effect of IL2 and TNF on the differentiation of LGL into LAK effectors. In the present study, we have further investigated the molecular basis of this synergistic mechanism and examined the role of TNF in the induction of LAK activity. We show that the generation of optimal LAK activity by low doses of IL‐2 in the presence of TNF involves the induction of high‐affinity IL2 receptors on LGL and occurs without promoting significant proliferation, suggesting a functional activation rather than a proliferative expansion of LAK precursors. Using blocking studies with anti‐Tac and with an anti‐IL2 (IHII), which specifically inhibits the binding of IL2 to the p75 IL2 receptor component, we also show that both the p55 and the p75 are involved in the increase in TNF binding sites on LGL and the subsequent acquisition of LAK activity. We also demonstrate that the failure of low doses of IL2 to induce LAK activity is related to their incapacity to induce TNF production. Moreover, when specific antibodies against TNF were added to the culture, the differentiation of LGL into LAK effectors by optimal concentrations of IL2 in our system (2.5–5.0 ng/ml) was partially inhibited. This suggests that TNF may be a physiologic mediator in the sequential activation stages of LGL into LAK effectors.
A case‐control investigation of cancer of the oral tongue and the floor of the mouth in Southern India
Authors: Sankaranarayanan R. , Duffy Stephen W. , Day Nicholas E. , Nair M. Krishnan , Padmakumary G.
Published: February 2007

A case‐control study of cancer of the oral tongue and floor of mouth was conducted in Kerala, Southern India, on 228 cases and 453 hospital‐based controls, matched for age, sex and religion. We studied pan(betel)‐tobacco‐chewing, bidi (local type of cigarette)‐and‐cigarette‐smoking, alcohol‐drinking and snuff use, for their associations with risk, in males. Among females, only pan‐tobacco‐chewing was analyzed, as very few females indulged in the other habits. In males, a significantly increased risk was observed in association with pan‐tobacco‐chewing, bidi‐smoking, bidi‐plus‐cigarette‐smoking (but not cigarette‐smoking alone) and alcohol‐drinking (p < 0.001 in all cases), although the effect of alcohol was no longer significant when adjusted for the other significant predisposing factors. Among females, pan‐tobacco‐chewing had a similar predisposing effect to that observed in males (p < 0.001). In males an adjusted relative risk of 6.14 was associated with chewing 10 or more pan‐tobacco quids per day (relative to those who never chewed). The corresponding relative risk in females was 9.27. In males, an adjusted relative risk of 7.46 was observed for those smoking 20 or more bidis per day (relative to never‐smokers).
Risk of bladder cancer by source and type of tobacco exposure: A case‐control study
Authors: Burch J. D. , Rohan T. E. , Howe G. R. , Risch H. A. , Hill G. B. , Steele R. , Miller A. B.
Published: February 2007

The association between tobacco use and risk of bladder cancer was investigated in a population‐based case‐control study conducted in Alberta and south‐central Ontario, Canada, between 1979 and 1982. In all, 826 histologically‐confirmed cancer cases and 792 randomly selected controls, individually matched to cases for age, sex, and area of residence, were recruited into the study. Compared to those who had never smoked cigarettes, males and females who had ever smoked cigarettes had a statistically highly significant 2‐fold increase in risk of bladder cancer; for ex‐smokers, the risk was intermediate between that for current smokers and never‐smokers. There was a dose‐dependent increase in risk of bladder cancer with total lifetime cigarette consumption, of similar magnitude for males and females. In males, risk increased with self‐reported degree of inhalation in ex‐smokers and in current smokers (statistically significant trend), while in females there was no association in current smokers, and a statistically significant inverse association in ex‐smokers. Overall, risks of bladder cancer associated with lifetime consumption of plain and filter cigarettes were similar, and there was little evidence to suggest that switching from plain to filter cigarettes was beneficial. Neither passive smoking nor other forms of tobacco consumption (pipes, cigars, chewing tobacco, or snuff) were associated with altered risk of bladder cancer. The population attributable risk for cigarette smoking was about 47% in males and about 33% in females.
Expression of c‐sis and other cellular proto‐oncogenes in human sarcoma cell lines and biopsies
Authors: Fahrer Claus , Brachmann Rainer , von der Helm Klaus
Published: February 2007

Six biopsies (4 of human fibrosarcomas, I of a B‐cell lymphoma and I of a normal lymph node from a melanoma patient) and 6 cell lines (derived from 5 different human osteosarcomas and from I rhabdomyosarcoma), together with control cells, were examined for the expression of c‐sis, c‐fosand c‐myc. The expression of c‐sis/PDGF‐B‐related proteins was also examined in cultured cells (not in biopsies). In situ hybridization studies further showed that the occurrence and level of expression of c‐sis mRNA and c‐sis/PDGF‐B‐related proteins were significant in the tumor cells. Expression of c‐fos and c‐myc mRNA did not correlate with c‐sis expression. Southern blot analysis of c‐sis, c‐fos and c‐myc of 20 DNAs of cell lines derived from human sarcoma or biopsies showed an identical pattern for BamHI and EcoRI restriction fragments of c‐sis(except for I fibrosarcoma biopsy), implicating no gene rearrangement as a cause of enhanced proto‐oncogene expression. The nucleotide sequence of c‐sis is highly homologous to that of the viral v‐sis oncogene which is capable of transforming infected cells. We conclude that enhanced expression of c‐sis in the sarcomas we have examined is involved in the initiation and/or maintenance of the cell transformed state.
Differential response to 1,3‐bis (2‐chloroethyl)‐1‐nitrosourea in drug‐resistant and ‐sensitive 9L rat brain tumor cells pretreated with α‐difluoromethylornithine and 6‐thioguanine
Authors: Hunter Karl J. , Deen Dennis F. , Marton Laurence J.
Published: February 2007

Pretreatment of 9L cells with either α‐difluoromethylorni‐thine (DFMO), which depletes intracellular levels of poly‐amines, or 6‐thioguanine (6TG), which substitutes for guanine in DNA, potentiates the cytotoxic effects of 1,3‐bis (2‐chloroethyl)‐1‐nitrosourea (BCNU). We examined the effects of these 2 agents in combination on the cytotoxicity of BCNU in sensitive (9L) and resistant (BTRC‐19) rat brain tumor cell lines. 9L cells were incubated with 0.2 μM 6TG for 72 hr; during the last 48 hr, I mM DFMO was added to cell cultures. The cytotoxicity of BCNU in pretreated cells was increased in an additive manner compared with the effects of each agent alone. Results of experiments in which the BCNU‐resistant BTRC‐19 cell line was treated similarly showed that only 6TG enhanced BCNU cytotoxicity. Flow cytometry studies showed that these effects are not related to cell‐cycle processes.
Effect of IFN‐γ treatment and in vivo passage of murine tumor cell lines on their sensitivity to lymphokine‐activated killef (LAK) cell lysis in vitro; association with H‐2 expression on the target cells
Authors: Tsai Li , Öhlén Claes , Ljunggren Hans‐Gustaf , Kärre Klas , Hansson Mona , Kiessling Rolf
Published: February 2007

Interferon‐gamma (IFN‐γ) treatment or in vivo passage of the murine YAC‐I lymphoma resulted in reduced sensitivity to in vitro lysis by syngeneic murine spleen cells cultured in rlL‐2 (LAK‐cells). IFN‐γ treatment also rendered the murine BI6 melanoma less sensitive to lysis by syngeneic LAK cells, whereas in vivo passage did not alter LAK sensitivity. The reduction in sensitivity to lysis correlated with enhanced expression of cell surface H‐2 on the target cells. The possible role of H‐2 was studied with a β2‐microglobulin‐deficient, and thus H‐2‐deficient, variant of the YAC‐I lymphoma. This variant line remained H‐2 negative even after IFN‐γ treatment or in vivo passage, and was highly sensitive to LAK‐cell‐mediated lysis, even after IFN‐γ treatment or in vivo passage. The present results are discussed in relation to IFN‐γ and in vivo induced modulation of MHC class‐l molecules on target cells and the possible consequences for interaction with activated as well as “natural” effector cells.
NK sensitivity and lung clearance of MHC‐class‐I‐deficient cells within a heterogeneous fibrosarcoma
Authors: Algarra Ignacio , Ohlén Claes , Perez Matias , Ljunggren Hans‐Gustaf , Klein George , Garrido Federico , Karre Klas
Published: February 2007

The present study examines clonal variations in NK sensitivity in a methylcholanthrene‐induced fibrosarcoma. Previous studies of clones from this tumor have shown considerable heterogeneity in H‐2 expression, and an association between deleted or low levels of class‐l products and increased tumorigenicity after subcutaneous implantation in immunocompetent syngeneic mice. Here, fibrosarcoma clones with no or low expression of MHC‐class‐l products were found to be sensitive to NK‐mediated lysis, while clones with high levels of MHC‐class‐l expression were relatively resistant. One H‐2+ (G2) and one H‐2− (B9) clone were chosen for more detailed studies. Cold‐target competition assays and conjugate cytotoxicity assays in agarose showed that splenic effector cells bound equally well to the H‐2+ and H‐2− tumor clone, although only the latter was sensitive to NK cell lysis. Treatment with 50 U/ml of rlFN‐γ for 48 hr increased the levels of H‐2 expression and made both clones more resistant to NK‐mediated lysis. In vivo studies with radiolabeled tumor cells showed that cells from the H‐2+ clone survived better than cells from the H‐2− clone in the pulmonary capillary bed after i.v. inoculation. This difference disappeared in mice treated with anti‐asialo GM, serum, known to deplete NKcell activity.
Evidence that β1‐6 branched Asn‐linked oligosaccharides on metastatic tumor cells facilitate invasion of basement membranes
Authors: Yagel Simcha , Feinmesser Raphael , Waghorne Carol , Lala Peeyush K. , Breitman Martin L. , Dennis James W.
Published: February 2007

In previous studies we have shown that the ability of murine tumor cells to metastasize in situ is directly linked to expression of ‐GIcNAcβ1‐6Manαl‐6Manßi‐branched complex‐type Asn‐linked oligosaccharides in tumor‐cell glycoproteins. Here we demonstrate that cell‐surface expression of β1‐6 branched oligosaccharides in metastatic tumor cells is specifically associated with increased invasion of human amnion basement membranes in vitro. Compared to non‐metastatic SPI murine mammary carcinoma cells, 2 metastatic sublines expressed higher levels of β1‐6 branched oligosaccharides and were found to be invasive but poorly adhesive on the amnion basement membrane. Swainsonine, a non‐toxic inhibitor of β1‐linked oligosaccharide processing which blocks the pathway prior to initiation of the β1‐6 linked antenna, blocked metastatic tumor‐cell invasion and increased adhesiveness. Swainsonine and the metalloprotease inhibitor O‐phenanthroline inhibited invasion, apparently via independent mechanisms. O‐phenanthroline did not affect tumor‐cell adhesion to the amnion basement membrane and swainsonine did not block secretion of metalloproteases, β‐hexosaminadase or tissue plasminogen activator activity by the tumor cells. These results suggest that tumor‐cell invasion of basement membranes requires both secretion of hydrolase activities and expression of β1‐6 branched complex‐type oligosaccharides at the tumor cell surface, such oligosaccharides being associated with reduced tumor‐cell adhesion to extracellular matrix.
CD 16 surface molecules regulate the cytolytic function of CD3−CD16+ human natural killer cells
Authors: Moretta Alessandro , Tambussi Giuseppe , Ciccone Ermanno , Pende Daniela , Melioli Giovanni , Moretta Lorenzo
Published: February 2007

Monoclonal (IgG) antibodies (MAbs) directed to CD 16 molecules efficiently induced lysis of the IgG‐binding P815 target cells. A similar effect was observed with selected anti‐CD2 MAbs. While combinations of 2 appropriate anti‐CD2 MAbs were required for induction of T lymphocyte activation, single stimulatory anti‐CD2 MAbs were sufficient for inducing cytolytic function in CD3−CDI6+ lymphocytes. In order to study possible regulatory mechanisms existing in the process of activation and induction of the cytolytic machinery of CD3−CDI6+ effector cells, we utilized the anti‐CDI6 OKNK MAb. Being of IgM isotype, the OKNK MAb does not allow cross‐linking between CD3−CDI6+ lymphocytes and target cells. Pre‐treatment of effector cells with OKNK MAb sharply inhibited the target cell lysis induced by either anti‐CD 16 (IgG) MAbs or stimulatory anti‐CD2 MAb. Moreover, a strong inhibitory activity of PHA‐induced target cell lysis and even of “spontaneous” lysis (at high effectontarget ratio) was observed. In contrast, in CD3+CDI6+ clones, OKNK MAb selectively inhibited the cell triggering induced by anti‐CD 16 MAbs (but not by anti‐CD3, anti‐CD2 MAbs or PHA). Our data indicate that CDI6 receptor molecules expressed by CD3−CD16+ lymphocytes down‐regulate cell responses to anti‐CD2 MAbs or PHA, and then exert a regulatory role in the cytolytic function of these cells.
Regulation of epidermal growth factor receptor by progestins and glucocorticoids in human breast cancer cell lines
Authors: Ewing Tania M. , Murphy Liam J. , Ng Mee‐Lian , Pang Grace Y. N. , Lee Christine S. L. , Watts Colin K. W. , Sutherland Robert L.
Published: February 2007

Human breast cancer cells secrete a number of autocrine peptides which modulate their proliferation rates. The known effects of steroid hormones on breast cancer cell proliferation may be mediated in part by altering the production of these growth factors and/or their interactions with cellular receptor sites. Receptors for epidermal growth factor (EGF), which also bind the autocrine growth factor, α‐transforming growth factor, are present on a number of breast cancer cell lines and it has previously been shown that T‐47D and MCF‐7 cells respond to progestins with an increase in the concentration of EGF receptors (EGF‐R). In the present study we examined the effects of both progestins and glucocorticoids on EGF binding in 10 human breast cell lines. Five of these lines were progesterone receptor positive and all lines expressed the glucocorticoid receptor (GR). All cell lines were initially incubated for 24 hr with increasing concentrations of the synthetic progestin, medroxyprogesterone acetate (MPA), and the level of specifically bound EGF was determined. An increase in specific binding of EGF was confirmed in two PR‐positive lines but, in addition, increases in EGF binding were observed in 4 PR‐negative cell lines. In these last lines the synthetic glucocorticoid, dexamethasone, was a more potent inducer of EGF binding than MPA, a known glucocorticoid agonist, while the high‐affinity PR ligand, ORG 2058, was without effect. Furthermore, MPA competed with dexamethasone for binding to GR in these cell lines, supporting the view that the induction of EGF binding by MPA in these cells was mediated via the GR. This conclusion was further supported by studies in which addition of the glucocorticoid and progestin antagonist, RU 486, inhibited the effect of ORG 2058 in two cell lines and completely abrogated the effect of dexamethasone in two other lines. Detailed binding studies revealed that the increase in EGF binding was accompanied by an increase in the concentration of EGF‐R. This effect was observed when EGF binding was assayed at either 0° or 37°C. Further studies demonstrated that the increases in EGF binding following ORG 2058 and dexamethasone treatment were accompanied by increases in EGF‐R mRNA levels. Our data illustrate that the binding of EGF by some human breast cancer cells can be regulated by both progestins and glucocorticoids acting vía their respective receptors and inducing increases in EGF‐R mRNA levels.
In vitro infection of cell lines with HTLV‐I and SIVmac results in altered intracellular free calcium concentration and increased membrane polarization
Authors: Wright K. A. , Olsen R. G.
Published: February 2007

This study was designed to determine whether retrovirus infection alters basal concentrations of intracellular free calcium, the magnitude of intracellular free calcium change upon receptor‐mediated cell‐stimulation, and cell membrane polarization. Two retrovirus‐infected cell lines were utilized: HTLV‐I‐infected MT‐2 cells and SIV‐infected H‐9 cells. Uninfected H‐9 cells were used as controls. The results show that the retrovirally‐infected cells had an increased basal concentration of intracellular free calcium when compared with the control cells and also a reduced magnitude of intracellular free calcium response to receptor‐mediated cell stimulants. The retrovirally‐infected cell membranes were also hyperpolarized when compared with the control cells.
Lymphocyte homing receptors and adhesion molecules in intravascular malignant lymphomatosis
Authors: Jalkanen S. , Aho R. , Kallajoki M. , Ekfors T. , Nortamo P. , Gahmberg C. , Duuvestun A. , Kalimo H.
Published: February 2007

Intravascular malignant lymphomatosis (IML) is a highly malignant, recently recognized form of lymphoma. It is characterized by multifocal proliferation of malignant lymphocytes within small blood vessels, primarily in the central nervous system and skin, frequently resulting in circulatory disturbances. The cause of the impaired capability of the malignant lymphocytes to extravasate has remained unclear. We analyzed the presence of immunoreactivity for certain homing receptor and adhesion molecules associated with lymphocyte extravasation in 3 patients with this disease. Compared with nonneoplastic leukocytes, large malignant lymphocytes appeared either negative or only weakly positive for the leukocyte surface glycoprotein, CD 18 that is the beta chain of the CD 11 a/CD 18 complex (lymphocytefunction associated antigen‐1, LFA‐1), which mediates cell‐to‐cell adhesion of lymphocytes. On the other hand, antibody to one of the proposed ligands for this complex, intercellular adhesion molecule‐1, gave positive reactivity both on lymphocytes and on endothelial cells. Further, the malignant lymphoid cells stained positively with Hermes‐3 antibody, which recognizes a common structure of CD44 class of molecules involved in lymphocyte homing. It was also shown that HECA‐452 antigen, a marker of high endothelial venules (HEV) supporting lymphocyte extravasation, can be synthesized by an IML patient even at the site of inflammation but it is not prerequisite for extravasation of inflammatory lymphocytes. Our results suggest that the deficiency or absence of the adhesion molecule CD 11 a/CD 18 may contribute to the inability of the malignant lymphoid cells to extravasate in IML, and perhaps also to the high malignancy of this form of lymphoma.
Human yolk‐sac tumor antigen 2G10: Biochemical characterization and significance as a serum antigen
Authors: Tanaka Shigeki , Fujimoto Junichiro , Jshii Eizaburo , Hata Jun‐Ichi
Published: February 2007

The biochemical characterization of human yolksac tumor (YST) antigen 2G10, detected by monoclonal antibody (MAb) M912‐2G10, was studied. Previous results indicated that glycolipids having a nonreducing terminal N‐acetyllactosamine structure were the epitope of 2G10 on human erythrocytes. In this study, the glycoprotein nature of 2G10 on the infantile embryonal carcinoma line, MTE, was investigated. 2G10 activity, measured by a new enzymelinked immunosorbent assay (2G10‐ELISA), was recovered in residual fractions of MTE from which glycolipids were removed. Chromatographically, 3H‐galactoselabelled 2G10 on MTE had a molecular weight (mw) of about 580 kDa, which decreased after pronase or alkalineborohydride treatment. Our results indicate the glycoprotein nature of 2G10 on MTE. Furthermore, 2G10, both on erythrocytes and on MTE, was sensitive to galactosidase but not to neuraminidase and fucosidase, suggesting that terminal galactose is involved in the antigenic structure. It was also found by 2G10‐ELISA that 2G10 sheds from tumor cells. Shedding occurs in nude mice transplanted with MTE as well as in patients with germ‐cell tumors (GCTs). The serum level of 2G10 in nontumor patients was low, but high levels were detected in patients with YSTsand with GCTshaving YST components. Immunohistochemically, the presence of 2G10‐positive YST components was shown in patients who had high serum levels of 2G10. Sera from other urogenital and childhood solid tumors did not have elevated 2G10. The mw of shed 2G10 was lower than that of 2G10 on the cell surfaces. Our results clearly indicate the usefulness of serum 2G10 as a tumor marker for GCTshaving YST components.
Amplification of c‐myc and c‐erbB‐2 proto‐oncogenes in human solid tumors: Frequency and clinical significance
Authors: Gutman M. , Ravia Y. , Assaf D. , Yamamoto T. , Rozin R. , Shiloh Y.
Published: February 2007

Molecular probes for cellular protooncogenes have recently been extensively used in order to search for functional and structural alterations in tumor tissues. Variable, and sometimes contradictory, results have been obtained regarding the frequency and clinical significance of amplification of the cmyc and cerbB‐2 protooncogenes in different series of human solid tumors. We addressed this question by performing Southern blotting analysis on 131 primary adult solid tumors of various tissues and 5 metastases of unknown origin, using molecular probes for both genes. Amplification of cmyc was found in 5 of the primary tumors, and amplification of cerbB‐2 in 5 others. In 2 tumors of the latter group, the cerbB‐2 gene was also rearranged. The distribution of these 10 tumors with regard to clinical stage and course of the disease did not point to an association between the amplification events and specific stage or prognosis. We concluded that, in this series, the amplification of both protooncogenes was occasional and was not a prognostic marker.
Expression of the pS2 gene in normal, benign and neoplastic human stomach
Authors: Luqmani Yunus , Bennett Caroline , Paterson Iain , Corbishley Catherine M. , Rio Marie‐Christine , Chambon Pierre , Ryall Glenys
Published: February 2007

The expression of the estrogenregulated breastcancerassociated pS2 gene was examined in 75 stomach resections taken from 45 patients. The 600‐base pS2 mRNA was found in all of the 47 nonneoplastic samples at varying levels: in the histologically normal group we observed a Poissontype distribution, whereas 79% of the tissues exhibiting dysplastic features expressed high levels of transcript. Tumour samples expressed relatively lower pS2 mRNA, with only 18% having high levels and 43% with no detectable expression. These differences were not correlated to tumour grading, stage or site. No amplification or rearrangement of the pS2 gene was found. Immunohistochemical analysis of formalinfixed paraffin sections, using a polyclonal antibody against pS2 protein, showed specific staining of both cytoplasm and membrane of epithelial cells in the neck region of antral and body glands as well as in luminal secretions. Immunoreactivity was observed in the subnuclear region of foveolar cells, with specialized gland and goblet cells in atrophic gastritis being negative. Heterogeneous but strong focal cytoplasmic staining was seen in tumour cells as well as in dysplastic epithelium. Two gastric cell lines, KATO III and MKN‐45, derived from poorly differentiated adenocarcinomas also expressed pS2, whereas 3 other lines from well differentiated parental tumours did not. Genomic analysis revealed a BamHI polymorphism in Kato III cells and in the nonexpressing MKN‐28 cells. Immunostaining to pS2 protein was also demonstrated in the cytoplasm of KATO III cells, but neither these nor any of 30 tissues examined showed any positivity with a monoclonal antibody (MAb) to estrogen receptor. Our results suggest that pS2 is normally expressed in human stomach, possibly in association with secretory activity, and becomes downregulated during malignancy.
Is chronic sunlight exposure important in accounting for increases in melanoma incidence?
Authors: Gallagher Richard P. , Elwood J. Mark , Yang C. Paul
Published: February 2007

Most attempts to relate changes in patterns of sunlight exposure to the rise in incidence of malignant melanoma have concentrated on the positive association between intermittent exposure to sunlight and risk of melanoma. The Western Canada Melanoma Study, however, also detected a significant inverse association between melanoma and chronic or longterm occupational sun exposure in men, with the lowest risk (OR = 0.5) in those with maximum occupational exposure, suggesting that chronic exposure may be protective. Data obtained from Canadian census figures indicated that since 1951 there has been a substantial reduction in the number of males engaged in outdoor occupations in Canadian society. These observations suggest that part of the increase in the incidence of melanoma in lowsunlight areas may be due to a reduction over the past 40 years of the size of this group of individuals “protected” by their exposure to UV light.
Correlation of HLA‐D/Ii antigen expression in breast carcinoma with local lymphohistiocytic infiltration reveals considerable dysregulation in a subset of tumors
Authors: Koretz Karin , Moldenhauer Gerhard , Majdic Otto , Möller Peter
Published: February 2007

Non‐neoplastic mammary glands and 203 carcinomas of the breast were examined immunohistochemically for expression of HLA‐DR, ‐DP, and ‐DQ molecules and the HLA‐D‐associated invariant chain (li). According to the reaction of normal breast epithelium in the course of chronic inflammation, these antigens were found to be induced in 120 carcinomas. In 106 of these the order was li ≥ HLA‐DR ≥ HLA‐DP ≥ HLA‐DQ. The extent of induction of these sequentially expressed antigens correlated with the density of local lympho‐histiocytic infiltration (li: p = 0.003; HLA‐DR: p = 0.0005; HLA‐DP: p = 0.0000005; HLA‐DQ: p= 0.01). Therefore, li/ HLA‐D antigen expression of carcinoma cells in local association with inflammation was regarded as an adequate reaction. The presence of these antigens in the absence of inflammation was regarded as “inadequate hyper‐expression”, and was found in 14 cases involving li, in 8 involving HLA‐DR, and in 1 case each involving ‐DP and ‐DQ molecules. In contrast, 20 cases expressed minimal/no li despite heavy inflammatory infiltration. This “inadequate hypo‐expression” was also found in 25 cases involving HLA‐DR, in 30 involving ‐DP and in 40 involving ‐DQ determinants. Combining the 2 variants showed that at least 54 cases (26.6%) were characterized as being dysregulated. “Adequate vs. inadequate li/HLA‐D antigen expression” did not correlate with tumor grading and might therefore be an independent parameter.
Urinary excretion of N‐nitrosamino acids and nitrate by inhabitants of high‐ and low‐risk areas for stomach cancer in Poland
Authors: Zatonski W. , Ohshima H. , Przewozniak K. , Drosik K. , Mierzwinska J. , Krygier M. , Chmielarczyk W. , Bartsch H.
Published: February 2007

Urine samples were collected from 96 inhabitants of a high‐risk rural area and a low‐risk urban area for stomach cancer in Poland, according to the following protocol: (1) when they were undosed; (2) after ingestion of proline 3 times a day; and (3) after ingestion of proline together with vitamin C 3 times a day. The samples were analyzed for N‐nitrosamino acids and nitrates, as indices of exposure to preformed and endog‐enously formed N‐nitrosamines. The median values of N‐nitrosoproline (NPRO) and N‐nitrosothiazolidine 4‐carboxylic acid (NTCA) excreted in the urine of undosed subjects were not different between the two areas; but N‐nitrososarcosine and 3‐(N‐nitroso‐N‐methylamino)propionic acid levels were 3‐ to 4‐fold higher in subjects of the high‐risk area. After intake of proline, the NPRO level increased (p < 0.02) only in subjects in the high‐risk area; intake of vitamin C tended to inhibit this increase in NPRO and lowered the levels of other nitrosamino acids. The urinary level of nitrates was 1.4‐fold, but significantly higher among subjects in the high‐risk area than among those in the low‐risk area; nitrate levels were not correlated with the amounts of cured meat or types of vegetables consumed. Urinary nitrate levels and excretion of NPRO, NTCA and the sum of all nitrosamino acids analyzed showed positive, though modest, correlations. These results indicate a higher potential for endogenous nitrosamine formation, possibly by intragastric nitrosation among subjects in the high‐risk rural area.
Monoclonal antibody against human squamous‐cell‐carcinoma‐associated antigen
Authors: Tatake Revati J. , Amin Kishore M. , Maniar Hina S. , Jambhekar Nirmala A. , Srikhande Sumati S. , Gangal Sudha G.
Published: February 2007

Mouse monoclonal antibody (MAb) 3F8E3 (lgG3k) was developed against the head and neck cancer cell line LICR‐LON‐HN2. Subjected to indirect immunofluorescence, the MAb reacted exclusively with SCC cell lines and showed no reactivity with normal or transformed mouse and human non‐SCC cell lines and hematopoietic cell lines. The radiolabeled MAb showed an affinity constant of 1.8 × 108 M−1 with HN2 cells and identified 2.07 × 104 sites/cell by Scatchard analysis. It identified 2 peptides from membrane extracts of HN2 cells by Western blotting. Avidin‐biotin‐complexed im‐munoperoxidase staining on cryostat sections of tumors from various tissues revealed that 3F8E3 reacted mainly with the membrane antigens of well differentiated SCC cells of oral cavity, larynx, esophagus, lung, uterine cervix, metastatic nodes of patients with oral cancer, and dysplastic cells in oral leukoplakia. The MAb did not react with poorly differentiated cells of Ca esophagus, adenocarcinoma of breast, stomach and colon, renal‐cell carcinoma and soft‐tissue sarcoma.
Preservation of chromosome and DNA characteristics of human colorectal adenocarcinomas after passage in nude mice
Authors: Lefrançois Danielle , Olschwang Sylviane , Delattre Olivier , Muleris Martine , Dutrillaux Anne‐Marie , Thomas Gilles , Dutrillaux Bernard
Published: February 2007

Twenty‐seven human colorectal adenocarcinomas were implanted s.c. into nude mice. A comparative study of chromosomes and DNA between fresh tumor (FT) and xenografted tumor cells (XT) could be performed in 9 cases. Losses or deletions were consistently found in FTs as well as in XTs, particularly on chromosomes 17 and/or 18. This was correlated with loss of heterozygosity for these chromosomes. Comparison between corresponding FT and XT karyotypes showed great similarities. However, the tendency toward polyploidization, which exists in FTs, appeared to be more pronounced in XTs. Passage in nude mice makes it possible to repeat cytogenetic analyses in order to obtain interpretable metaphases. Xenografting not only increases the number of tumorigenic cells, but also eliminates human normal stromal or blood cells and gives unambiguous data on allelic loss.