bluuebunny/crossref_metadata_2025 huggingface dataset:
Altered expression of basement‐membrane components and collagenases in ascitic xenografts of OVCAR‐3 ovarian cancer cells
Authors: Liebman Jeffrey M. , Burbelo Peter D. , Yamada Yoshihiko , Fridman Rafael , Kleinman Hynda K.
Published: February 2007

Ascitic ovarian cancer cells, which derive from solid tumors, complicate the treatment of ovarian cancer by spreading throughout the peritoneal cavity. Because basement‐membrane components may influence tumor‐cell proliferation and dissemination, the present studies examined the production of (a) basement‐membrane attachment and migration factors (laminin, fibronectin and type IV collagen); (b) a laminin receptor, the 32/67‐kDa laminin‐binding protein, the presence of which correlates with malignancy; and (c) metalloproteinases (types I and IV collagenase and stromelysin), by ascitic and cultured OVCAR‐3 cells and solid OVCAR‐3 tumors. The cultured cells and solid tumors produced high levels of mRNA encoding attachment factors and metalloproteinases, and low levels of mRNA for the 32/67‐kDa laminin receptor. In contrast, the ascitic ovarian cells had low or undetectable levels of mRNA encoding laminin, type IV collagen and metalloproteinases, but higher levels of transcripts for the laminin receptor. Our results suggest that the apparent inability of ascitic OVCAR‐3 cells to attach to host‐tissue surfaces may be a consequence, in part, of low levels of expression of laminin, type IV collagen and/or type IV collagenase. © 1993 Wiley‐Liss, Inc.
Correlation between the growth‐inhibitory effect of TGF‐β1 and phenotypic characteristics in a panel of B‐cell lines
Authors: Altiok Aysin , Ehlin‐Henriksson Barbro , Klein Eva
Published: February 2007

Human B‐cell lines established from Burkitt lymphoma (BL) and normal B cells immortalized in vitro by EBV (LCLs) differ in phenotype. While the BL correspond to resting B cells, the LCLs resemble activated B cells. When BLs which have the EBV genome are carried in vitro, they acquire some of the features of LCLs, such as expression of B‐cell activation markers and the tendency to form aggregates. Comparison of several B‐cell lines for sensitivity to TGF‐β showed that the growth of BLs (with few exceptions), but not of the LCLs, was inhibited. The results suggested that the sensitivity to TGF‐β correlates with the cellular phenotype. In the present work, this assumption is even more critically substantiated by studying 2 sublines of an EBV‐genome carrying BL line, Mutu, which were selected for single cells and aggregates. The former (with resting phenotype) was inhibited, while the subline of aggregated cells, which also expressed B‐cell activation markers, was not inhibited. Somatic‐cell hybrids between BLs, LCLs and non‐B cells provided lines with phenotypic differences. Results with a panel of such hybrid lines also showed that those which express the activated B‐cell phenotype are not inhibited by TGF‐β. Differences in the levels of expression of activation markers did not influence the response to TGF‐β. © 1993 Wiley‐Liss, Inc.
Cytokines as adjuvants: Effect on the immunogenicity of NeuAcα2‐6GalNAcα‐O‐Ser/Thr (sialyl‐Tn)
Authors: Piera Mercé , de Bolós Carme , Castro Rosa , Real Francisco X.
Published: February 2007

Sialyl‐Tn, defined by monoclonal antibody (MAb) B72.3, shows restricted normal‐tissue distribution but is expressed in a wide variety of carcinomas. To analyze the immunogenicity of sialyl‐Tn, mice were immunized with ovine submaxillary mucin (OSM) in combination with monophosphoryl lipid A (MPLA), liposomes, or adjuvants that activate macrophages (rIL‐1, rlFN‐gamma, rM‐CSF, IL‐1‐derived peptides) or T cells (HL‐2). The level and specificity of the immune response were analyzed by ELISA. rIL‐l and rIFN‐gamma induced a very high and specific antibody response, whereas the effect of rM‐CSF was dose‐dependent: at a low dose it induced a high‐level specific antibody response and at the high dose level it induced a polyclonal non‐specific response. These results indicate that cytokines are powerful adjuvants which modulate both the magnitude and specificity of the immune response. More studies are necessary to determine the optimal doses in animal models and in active specific immunotherapy of patients with cancer. © 1993 Wiley‐Liss, Inc.
Human melanoma cells express a functional interleukin‐2 receptor
Authors: Plaisance S. , Rubinstein E. , Alileche A. , Han D. S. , Sahraoui Y. , Mingari M. C. , Bellomo R. , Rimoldi D. , Colombo M. P. , Jasmin C. , Carrel S. , Azzarone B.
Published: February 2007

Flow cytometric analysis reveals that 5 human melanoma cell lines (M14, IGR3, MEI 477, JUSO, GLL 19) express both α and β chain of the interleukin 2 receptor (IL‐2Rα and IL‐2Rβ). These chains are able to specifically bind IL‐2 and to form high‐affinity heterodimers (IL‐2Rαβ). Analysis of poly A+ RNAs by Northern blot reveals the presence of typical transcripts for both the IL‐2Rα gene (3.6 kb) and the IL‐2Rβ gene (4 kb). Reverse transcription/polymerase chain reaction analysis allowed transcripts for the IL.2Rγ (p64) gene to be detected in 3 of these melanoma cell lines (M 14, IGR3, ME 1477). Incubation with human recombinant IL‐2 modifies in IL‐2Rα+β+γ+ (M14) the expression of several surface molecules: down‐regulation of ICAM‐1, HLA class I and HLA‐DR and up‐regulation of CD44. IL‐2 is also active on IL‐2α+β+γ− cell lines since it decreases ICAM‐1 and HLA class‐II expression at the surface of JUSO cells. Down‐regulation of ICAM‐1, whose expression in melanoma cells is a marker of tumor progression, is detectable within 3 hr in MI4 cells and is maximal after 48 hr incubation, at IL‐2 concentrations corresponding to the high‐affinity heterodimers. This feature is specific since it is partially inhibited by MAbs directed against the IL‐2 binding site of the IL‐2Rα (MAR93, 10TI4) and IL‐2Rβ (MiKβ1, TU27) chains. Our data support the notion of a direct effect of IL‐2 on human melanoma cells. Modulation of the expression of surface molecules which is important for the interaction with immunocompetent cells or for tumor progression, could have a role to play during in vivo IL‐2 treatment of human melanomas. © 1993 Wiley‐Liss, Inc.
Diet and risk of gastric cancer. A population‐based case‐control study in Sweden
Authors: Hansson Lars‐Erik , Nyrén Olof , Bergström Reinhold , Wolk Alicja , Lindgren Anders , Baron John , Adami Hans‐Olov
Published: February 2007

A case‐control study to evaluate risk factors of gastric cancer was carried out in areas with contrasting incidence rates in Sweden. Face‐to‐face interviews were conducted with 338 of 456 eligible histologically confirmed gastric‐cancer cases and 669 of 880 eligible control subjects, sampled from population registers and frequency‐matched by age and gender. We focused on 2 periods, adolescence and 20 years prior to interview. The association of gastric‐cancer risk with dietary habits during adolescence were similar to that found for the period 20 years before interview; high consumption of wholemeal bread, fruit and vegetables was associated with reduced gastric‐cancer risk. In addition, cheese, fish and tea had a protective effect during adolescence. Increased gastric‐cancer risk was related to whole‐milk consumption, but this association decreased substantially in a multivariate analysis including vegetables. There was a positive relationship between gastric‐cancer risk and the age at which the interviewees started using refrigerators. This population‐based study confirmed the protective effect of a high consumption of vegetables and fruit in the development of gastric cancer, but failed to find any association between intake of meat, sausage, cold cuts, liver, salt, coffee, the habit of frying, smoking or grilling foods, and risk of gastric cancer.
Cancer incidence in estonian migrants to Sweden
Authors: Nilsson Bo , Gustavson‐Kadaka Evi , Rotstein Samuel , Hakulinen Timo , Rahu Mati , Aareleid Tiiu
Published: February 2007

Cancer incidence in Estonians who took refuge in Sweden in 1944‐1945 has been compared with that in the total Swedish population and that among Estonians in Estonia in 1974‐1985 using data from the Swedish and the Estonian countrywide population‐based cancer registries. The vast majority of the Estonian immigrants studied had been living in Sweden for 30 years when the follow‐up with respect to cancer incidence started in this investigation. In spite of the long residence in Sweden, differences in cancer incidence could be observed between these immigrants and the total Swedish population. The age‐standardized incidence of stomach cancer was higher in the Estonian migrants than in the total Swedish population (SIR = 1.6 and 2.1 for males and females, respectively). Breast cancer incidence was lower in the migrant women (SIR = 0.75) and lung cancer incidence higher in migrant men (SIR = 1.5). An increased incidence of colorectal cancer was also found for both sexes in the migrant population (SIR = 1.4 for both males and females). A comparison between Estonians in Estonia and the total Swedish population revealed that the cancer incidence for the Estonians was lower than expected at age 70 and over. Male lung cancer and stomach cancer showed a higher incidence in the Estonian population than in the Swedish and in the migrant populations. The migrant population showed an intermediate incidence relative to Estonians in Estonia and the entire Swedish population. The colon‐cancer risk in Estonian migrants to Sweden was higher than the risk for Estonians in Estonia and for the Swedish population. This contrasts with most findings in the present and other studies on intermediate risks of migrants compared to the risks in the country of origin and in the new country of residence.
Viral infections and chemical exposures as risk factors for hepatocellular carcinoma in Vietnam
Authors: Cordier S. , Thuy Le Thi Bich , Verger P. , Bard D. , Dai Le Cao , Larouze B. , Dazza M. C. , Quinh Hoang Trong , Abenhaim L.
Published: February 2007

A case‐control study investigating risk factors for hepatocellular carcinoma (HCC) was conducted in Hanoi, in the north of Vietnam, between 1989 and 1992. Male cases of HCC (152) diagnosed in 2 hospitals were included. Hospital controls (241) admitted mainly to abdominal surgery departments were frequency‐matched to cases for sex, age, hospital and place of residence (Hanoi, province). Odds ratios adjusted for matching variables and other potential confounders were estimated using unconditional logistic regression, or exact non‐parametric statistical inference when numbers were small. Positivity for hepatitis B surface antigen (HBsAg) was the main risk factor for HCC in this sample. Five subjects (3 cases, 2 controls) had been infected by hepatitis C virus (HCV), and none of them were carriers of HBsAg, giving an OR of 38 associated with HCV infection among HBsAg‐negative subjects. Alcohol drinking was associated with HCC and interacted with HBsAg positivity. Agricultural use of organophosphorous pesticides (30 liters/year or more) and military service in the south of Vietnam for 10 years or more were also associated with an increased risk of HCC. This study confirms the major role played by HBV infection and its association with HCC in south‐east Asia. It also suggests how other factors such as alcohol consumption or exposure to chemicals may interact with HBV infection.
Cancer incidence trends in women at high risk of human immunodeficiency virus (HIV) infection
Authors: Rabkin Charles S. , Biggar Robert J. , Baptiste Mark S. , Abe Toshi , Kohler Betsy A. , Nasca Philip C.
Published: February 2007

To determine the types and rates of tumors which may be associated with HIV infection in women, we used cancer incidence data from New York and northern New Jersey. We examined changes in incidence of selected cancers in women aged 20‐49 years and compared groups differing in incidence of AIDS. Black women were compared to white women in New York City and in the remainder of New York State; for cervical cancer, rates were also compared for Blacks and Whites in northern New Jersey. The incidence of Kaposi's sarcoma in women increased in New York City, beginning in 1982 for Blacks and in 1984 for Whites, but remained stable in the remainder of New York State. The incidence of non‐Hodgkin's lymphoma in New York women doubled in Blacks after 1982 whereas incidence trends in Whites were unchanged. No consistent variation was seen in the incidence of Hodgkin's disease. Cervical cancer in New York and northern New Jersey Blacks declined over the same period by approximately 40% for invasive tumors and 50% for in situ lesions. The HIV epidemic is associated with substantial excesses of Kaposi's sarcoma and non‐Hodgkin's lymphoma in women. The absence of Kaposi's sarcoma in upstate New York women suggests the existence of a geographically restricted co‐factor(s) for Kaposi's sarcoma in addition to HIV. If HIV affected cervical cancer incidence through 1988, its impact was small compared to the striking decreases which followed widespread adoption of Papanicolaou screening.
Diet and colorectal adenomas: A case‐control study in majorca
Authors: Benito E. , Cabeza E. , Moreno V. , Obrador A. , Bosch F. X.
Published: February 2007

A case‐control study on dietary factors and colorectal adenomas was conducted in the island of Majorca, Spain, from April 1987 to February 1990. Subjects were interviewed using a food frequency questionnaire. Nutrient and caloric intake was estimated using local food composition tables. The risk of colorectal adenomas was related to the consumption of sugar and pastries. Consumption of vegetables was highly protective, irrespective of the cooking procedures. Analyses by nutrients identified as protective factors fiber from fruits and vegetables, magnesium and zinc, and vitamins C, B6 and folic acid. No excess risk was found for alcohol drinking, intake of saturated fats or animal protein. Of the non‐dietary factors, sedentariness in the workplace and urban residence were the only risk factors identified.
Cytogenetic analysis of epithelial renal‐cell tumors: Relationship with a new histopathological classification
Authors: van den Berg E. , van der Hout A. H. , Oosterhuis J. W. , Störkel S. , Dijkhuizen T. , Dam A. , Zweers H. M. M. , Mensink H. J. A. , Buys C. H. C. M. , de Jong B.
Published: February 2007

Renal‐cell carcinomas (RCC) are clinically, histologically and cytogenetically very heterogeneous. The present histological WHO classification shows no clear correlation between histologic subtypes and specific chromosomal abnormalities. In 1986, a new classification was proposed by Thoenes and Störkel based on the cell type from which the tumor arises. They distinguish 5 cell types: clear‐cell, chromophilic, chromophobic, ductus Bellini and oncocytic. Results of 105 primary tumors show that, in this new classification, there is a correlation between different subtypes of renal‐cell tumor and specific chromosomal abnormalities at a microscopic and/or molecular level. The clear‐cell compact type shows structural aberrations of chromosomes 1, 3, 4, 5q, 6, 10q, 11 q and 12q, together with polysomy of chromosomes ×, 4, 5, 7, 10, 12, 15, 16, 19, 20, 21 and 22, monosomy of chromosomes 3, 8, 9, 13, 14, and loss of Y. The main characteristics of the chromophilic tubulo‐papillary type are trisomies 7 and 17, and loss of the Y‐chromosome. Chromophobic carcinoma seems to be correlated with, inter alia, polysomy 7, trisomies 12, 16, 18, 19, structural abnormalities of 11q, and telomeric associations. Oncocytomas do not reveal any specific chromosomal anomaly, except for trisomy 7. Loss of heterozygosity on 3p is only found in the clear‐cell compact type. Some specific chromosomal abnormalities correlate with a particular grade of the tumor. These correlations support the hypothesis that specific chromosomal abnormalities play a role in the histogenesis and oncogenesis of RCC. They may be important for tumor diagnosis and clinical prognosis.
Metalloproteinase and timp expression by the human breast carcinoma cell line 8701‐BC
Authors: Alessandro R. , Minafra S. , Pucci‐Minafra I. , Onisto M. , Garbisa S. , Melchiori A. , Tetlow L. , Woolley D. E.
Published: February 2007

It is widely accepted that collagenolytic enzymes are required to facilitate the invasion and spread of tumour cells into host tissues. Immunohistochemical, zymographic and PCR analyses have produced evidence that the recently established human mammary carcinoma cell line, 8701‐BC, expresses several metalloproteinases (MMP‐1, ‐2, ‐9 and ‐10) and their tissue inhibitors (TIMP‐1 and ‐2). Application of these different techniques has led to several observations, both complementary and dissimilar. Whereas PCR analysis showed that mRNA was detected for each of the proteins, the immunolocalization study demonstrated that MMP‐1, MMP‐2, MMP‐9 and TIMP‐1 production was restricted to only a proportion of the tumour cells, with no evidence of MMP‐3 or TIMP‐2 synthesis. Such observations suggested phenotypic heterogeneity within the cell line, which was further examined by use of the tumour cell clones BC‐3A and BC‐61 derived from the parental 8701 ‐BC line. Comparative studies using zymography and PCR analysis demonstrated differences in MMP‐2 and MMP‐10 expression between the 3 cultures. The data indicate that the 8701 ‐BC cell line retains an inherent capacity for metalloproteinase and TIMP expression, with the production of both interstitial collagenase (MMP‐1) and the 2 basement‐membrane‐degrading enzymes (MMP‐2 and MMP‐9) representing an aggressive collagenolytic pheno‐type. The concomitant production of TIMP‐1 by these cell cultures, and the apparent phenotypic heterogeneity displayed by these lines, suggest that metalloproteinase dysregulation may represent an important feature of clonal heterogeneity. Although the 8701‐BC and BC‐61 cells were much more invasive than those of the BC‐3A clone, as judged by the penetration of “Matrigel”, it has not yet been possible to relate this invasive potential to the metalloproteinase and TIMP profiles reported here for each cell line.
Retinoic‐acid‐induced augmentation of molecular species carrying sialosyl lewisa antigen in colorectal‐carcinoma cell cultures
Authors: Liepkalns V. A. , Icard‐liepkalns C.
Published: February 2007

In order to study the effects of vitamin‐A metabolites on long‐term carcinoma‐antigen secretion, colorectal‐carcinoma cells SWIII6 were cultured on membrane filters in totally synthetic media with 0 to 2.6 μM retinoic acid (RA). RA altered cell division, cell size and soluble‐sialosyl Lea (S‐Lea) secretion and S‐Lea accumulation within cells and apical‐membrane domains. Cultures treated with RA for 10‐12 days grew to lower cell densities (60% of controls) and contained more protein per cell (140% of controls). RA treated cells also had 5‐fold higher levels of S‐Lea in cells and secreted 9‐fold more S‐Lea into culture media assayed per 24 hr by (ELISA) 19‐9 monoclonal antibody binding. As total media S‐Lea increased, polarity of non‐lipid S‐Lea antigen secretion increased toward the interior (apical) media. High‐performance thin‐layer immunobinding showed that ganglioside S‐Lea was higher in RA‐fed cells, but could not be detected in apical media of RA‐fed or control cells after 24 hr. Western blots indicated that non‐lipid sialosyl Lewisa was bound to 150‐ to 180‐kDA molecular species principally in cells, but 210‐ to 300‐kDa molecular species appeared in the non‐lipid extract of media. Thus, the above RA alterations, monitored by 3 immunochemical techniques, include up to 9‐fold stimulation of “constitutive” 150‐ to 300‐kDa sialosyl‐Lewisa secretion, but ganglioside Lewisa is sorted differently and retained by apical membranes.
Adhesion to carcinoembryonic antigen by human colorectal carcinoma cells involves at least two epitopes
Authors: Jessup J. M. , Kim J. C. , Thomas P. , Ishii S. , Ford R. , Shively J. E. , Durbin H. , Stanners C. P. , Fuks A. , Zhou H. , Hansen H. J. , Goldenberg D. M. , Steele G.
Published: February 2007

Carcinoembryonic antigen (CEA) may be involved in both cell‐cell and cell‐substrate adhesion. Our purpose was to determine whether epitopes involved in the homophilic binding of human colorectal carcinoma cells to CEA participated in adhesion to basement membrane proteins. Three human colorectal adenocarcinoma cell lines and one CHO cell line transfected with CEA cDNA were tested in a solid‐phase adhesion assay. The 2 CEA‐expressing carcinoma cell lines (KM‐12c and CCL 188) and the transfectant, but not the parental CHO line, bound to CEA. The CEA‐non‐producing carcinoma line (Clone A) did not bind to CEA. All colorectal carcinoma cell lines, the transfectant and the parental CHO line bound to laminin, while the colorectal carcinoma lines bound to type‐IV collagen. MAbs to epitopes on CEA that cross‐react with non‐specific cross‐reacting antigen (NCA) inhibited adhesion of CEA‐expressing cells to CEA. MAbs to non‐cross‐reactive epitopes of CEA did not block adhesion to CEA. When the inhibitory anti‐CEA antibodies were compared in a competitive radioimmunoassay, 2 distinct epitopes were identified. Epitope I is in the N‐terminal domain and defined by MAbs MN3, T84.1 and C110, whereas epitope II is located in the repeating loop domains and is recognized by antibodies MN15, PR3B10 and NPI. None of the antibodies to epitope I or II blocked adhesion by KM‐12c or CCL 188 cells to laminin or type‐IV collagen. Thus, at least 2 different regions on CEA participate in adhesion to CEA but not to collagen or laminin by CEA‐expressing human colorectal carcinoma cells.
Spontaneous development of a chromosomal translocation 5;14 in an epstein‐barr‐virus‐associated b‐cell lymphoma in a SCID mouse
Authors: Glaser Ronald , Theil Karl S. , Bonneau Robert H. , Sheridan John F. , Vasquez Marco , Allen Carl M.
Published: February 2007

C.B‐17 SCID mice were inoculated with human peripheral blood leukocytes (PBLs) from normal Epstein‐Barr virus (EBV)‐seropositive and ‐seronegative donors. Confirmation of a functioning human immune response was demonstrated by the detection of human antibody after inoculation with rotavirus, tetanus toxoid, or EBV. One group of animals inoculated with PBLs from an EBV‐seropositive donor developed immunoblastic lymphomas approximately 9 weeks after transplantation. Confirmation of the species and sex of origin of the tumor cells was established using a spontaneous cell line prepared from the tumor. At passage I, the tumor‐cell line (AGTI) showed 15% of the metaphases with a translocation involving chromosomes 5 and 14. A lymphoblastoid cell line (AGLCL) established from the same PBLs from the same donor at the time of inoculation of the mice had a normal female karyotype. The AGLCL and a clone of AGTI cells were analyzed for rearrangement of immunoglobulin heavy chain (IgH) genes; both cell lines showed rearrangement of both IgH alleles. The results outlined in this report suggest that a spontaneous chromosomal translocation involving chromosome 14 occurred in normal PBLs in the SCID mouse.
Different expression patterns of oncogenes and proto‐oncogenes in hereditary and carcinogen‐induced tumors of xiphophorus
Authors: Mäueler Winfried , Schartl Angelika , Schartl Manfred
Published: February 2007

Hereditary melanoma in Xiphophorus hybrids carrying the melanoma‐inducing Tu‐Sd locus is caused by transcriptional activation of the Xmrk gene that resides at the Tu‐Sd locus and encodes a novel member of receptor tyrosine kinases (RTK). In this study, a total of 27 hereditary melanomas from various hybrid genotypes harbouring 7 different Tu alleles were also found to over‐express the corresponding Xmrk alleles. The level of over‐expression correlated with the degree of malignancy of the melanoma. In addition, Xsrc expression was high in many malignant melanomas. Expression patterns and levels of the Xiphophorus EGF‐receptor gene (Xerb B), the c‐myc (Xmyc), and the PDGF (Xsis) gene(s) were not intriguing. Transcription of the ras gene(s) may be correlated to secondary events of melanoma progression. Expression patterns of Xfms, the Xiphophorus CSF‐I receptor homologue, can be explained by different contents of infiltrating macrophages in the tumors. In carcinogen‐induced tumors including one melanoma no significant expression of the Xmrk oncogene could be detected. Xsrc expression, however, was strikingly high. This indicates that activation of oncogenes other than Xmrk is instrumental in tumorigenesis of neoplasia of non‐hereditary origin.
Determination of the specificities of monoclonal antibodies recognizing members of the CEA family using a panel of transfectants
Authors: Daniel S. , Nagel G. , Johnson J. P. , Lobo F. M. , Hirn M. , Jantscheff P. , Kuroki M. , von Kleist S. , Grunert F.
Published: February 2007

Carcinoembryonic antigen (CEA), one of the most clinically important tumor markers, is mainly used in the post‐surgical surveillance of patients with colorectal carcinomas. CEA belongs to a large protein family, which includes cross‐reacting antigens, e.g., non‐specific cross‐reacting antigens (NCAs) and biliary glycoprotein (BGP) as well as pregnancy‐specific glycoproteins (PSGs). The genes encoding these proteins can be subdivided into the CEA and PSG subgroups. The members of the subgroups share antigenic determinants and show high similarity in amino‐acid sequences. Their derived secondary structures show them to belong to the Immunoglobulin superfamily. Due to the close relationship of the members of the CEA subgroup, it is very difficult to distinguish between the individual members with MAbs. Here we have used flow cytometric analysis of transfectants expressing individual members of the CEA subgroup as an alternative approach to determine the specificities of 13 MAbs. This allows us to examine the specificities of these antibodies for members of the CEA family, even of those which have not yet been characterized at the protein level. In addition, binding of the MAbs to NCAs expressed by polymorphonuclear cells (PMN) was tested by Western‐blot analysis, immunoprecipitation and flow cytometry.

Four antibodies bound exclusively to NCA‐50/90 and one MAb (80H3) only to NCA‐95. MAb 4/3/17 recognizes CEA and BGP on the surface of transfectants and NCA‐160 from granulocytes. We assume that NCA‐160 is a product of the BGP gene. On granulocytes, which do not express CEA, MAb 4/3/17 is specific for NCA‐160 (BGP).

Mutual inhibition of the MAbs binding to NCA‐50/90 revealed 3 different epitope groups.
Inhibition of tumor growth and enhancement of metastasis after transfection of the γ‐interferon gene
Authors: Lollini Pier‐Luigi , Bosco Maria C. , Cavallo Federica , De Giovanni Carla , Giovarelli Mirella , Landuzzi Lorena , Musiani Piero , Modesti Andrea , Nicoletti Giordano , Palmieri Gabriella , Santoni Angela , Young Howard A. , Forni Guido , Nanni Patrizia
Published: February 2007

Cells from the spontaneous metastatic TS/A mammary adenocarcinoma of a BALB/c mouse were transfected with the murine γ‐interferon (IFN‐γ) gene. Six clones (IFN‐γ clones) releasing between 2 and 6,000 international units (IU) of IFN‐γ/ml culture medium, were compared to TS/A parental cells (TS/A‐pc) and to cells transfected with neomycin resistance gene only (NEO cells). Autocrine IFN‐γ up‐regulated membrane expression of H‐2 class‐1 and Ly‐6 glycoproteins, but did not alter cellular proliferation in vitro. All IFN‐γ clones gave rise to progressive tumors with a growth rate significantly slower than that of tumors induced by TS/A‐pc and NEO cells, and inversely correlated with the amount of IFN‐γ secreted. TS/A‐pc and NEO tumors displayed a marginal reactive infiltrate, whereas those formed by IFN‐γy clones were massively infiltrated mostly by macrophages. In T‐ and NK‐deficient mice the growth of tumors formed by I FN‐y clones was not enhanced. In vitro tests showed that IFN‐γ clone cells were markedly more lysed by macrophages than TS/A‐pc and NEO cells, while they remained poorly sensitive to NK and LAK cells. These data as a whole suggest that the development of solid tumors by IFN‐γ clones is primarily hampered by macrophages and not by T‐lymphocytes or NK cells. When spontaneous metastatic ability was compared, 2 IFN‐γ clones releasing 2‐4 IFN‐γ lU/ml were significantly more metastatic, while most IFN‐γ clones appeared to be as metastatic as NEO cells. By contrast, following intravenous challenge, all IFN‐γ clones produced 5‐10 times more experimental metastases than NEO cells. The higher metastatic ability of IFN‐γ clones was attributed to increased resistance to NK cells since, in NK‐depleted BALB/c mice, metastatic spread of IFN‐γ clones was not enhanced, whereas a 50‐fold increase in the number of metastases was found upon injection of NEO cells.
Presence of CD4+ T suppressor cells in mice rendered unresponsive to tumor antigens by intravenous injection of irradiated tumor cells
Authors: Rakhmilevich Alexander L. , North Robert J. , Dye Earl S.
Published: February 2007

We used in vivo and in vitro assays to determine whether suppressor cells are generated in mice rendered unresponsive to tumor‐specific antigens by intravenous (i.v.) injection of non‐replicating tumor cells. The results show that a single i.v. injection of 2 × 107 irradiated P815 tumor cells resulted in the induction of a state of specific unresponsiveness to tumor‐associated antigens, as revealed by the inability of the treated mice to achieve immunologically‐mediated regression of an intradermal P8 15 tumor containing C. parvum, or to generate effector T cells capable of causing rejection of a P815 tumor in T‐cell‐deficient (T × B) test recipients. Failure to respond to tumor antigens was associated with the presence in spleen of CD4+ T cells capable, on passive transfer, of suppressing adoptive T‐cell‐mediated tumor regression in T × B recipients. However, the same CD4+ suppressor cells failed to inhibit the generation of tumor‐specific cytotoxic T lymphocytes (CTL) in vitro. On the contrary, spleen cells from mice made unresponsive by i.v. injection of tumor cells were primed to generate CTL in response to tumor antigens in vitro. Taken together, our results suggest that unresponsiveness induced by i.v. injection of tumor antigens is an active process mediated, at least in part, by CD4+ T suppressor cells, and that these cells coexist in the spleen with antigen‐primed effector T cells with a capacity to generate tumor‐specific CTL when released from suppression in vitro.
Activation of cytolytic activity in peripheral blood
Authors: Galligioni Enzo , Quaia Michele , Spada Antonella , Monfardini Daniela Silvio
Published: February 2007

Our purpose was to evaluate the ability of blood monocytes of renal cancer patients to become cytotoxic against fresh, autologous tumor cells. Fresh target cells were obtained by mechanical and enzymatic dissociation of tumor and normal renal tissue. The A375 cell line, derived from a human melanoma, and the SW626 cell line, derived from a human ovarian carcinoma, were used as positive target cell controls. Monocytes from renal cancer patients and normal volunteers were activated in vitro with lipopolysaccharide (LPS), or muramyl tripeptide (MTP‐PE), or multilamellar vesicle liposomes containing MTP‐PE (MLV‐MTP‐PE), with or without a pre‐incubation with r‐IFN‐γ, and tested for cytotoxicity in a 72‐hr 111Indium‐release assay. All patients were tumor‐free at the time of the monocyte study. No difference in cytotoxic activity was observed between monocytes from healthy volunteers and those from cancer patients. Freshly dissociated tumor cells were as susceptible to tumoricidal monocytes as the 2 cell lines. Moreover, no cell population appeared to be resistant to activated monocytes, which were cytotoxic to both allogeneic and autologous fresh tumor cells. Activated monocytes maintained their ability to discriminate between normal and neoplastic cells and were not cytotoxic against autologous or allogeneic normal non‐neoplastic cells. Our data indicate that MLV MTP‐PE liposomes activate peripheral blood monocytes from cancer patients to a tumoricidal status against fresh, dissociated non‐cultured autologous tumor cells.
Quantification of HPV‐16 E6‐E7 transcription in cervical intraepithelial neoplasia by reverse transcriptase polymerase chain reaction
Authors: Hsu E. M. , McNicol P. J. , Guijon F. B. , Paraskevas M.
Published: February 2007

Human papillomavirus type 16 (HPV‐16) is associated with neoplastic lesions of the uterine cervix. Viral transforming functions have been localized to the E6‐E7 open reading frame (ORF) and this ORF is conserved consistently in cervical intraepithelial neoplasia (CIN). Two mRNAs, generated by alternative splicing, are expressed from the E6‐E7 ORF. These are known as E6*I and E6*II, and potentially encode the viral E7 and E6 proteins, respectively. It is believed that the HPV‐16 transforming ability is mediated by the E6 and E7 proteins. A quantitative RT‐PCR assay, developed by us to characterize the relative expression of E6‐E7 spliced transcripts, was applied to exfoliated cervical cells obtained from patients in varying stages of clinically defined CIN and who were infected with HPV‐16. The relationship between viral expression, disease stage, oral contraceptive use and age was studied. No association was observed between age or oral contraceptive use and HPV‐16 E6‐E7 expression. However, when both E6*I and E6*II were detected, a direct correlation was observed between relative proportions of E6*I/E6*II mRNAs greater than 95%/5% and increased disease severity. This study underscores the importance of the relationship between quantities of viral transforming gene transcript and the course of cervical disease. It also suggests that quantification of HPV‐16 E6‐E7 transcription may be useful as a prognostic tool to identify women who are at increased risk of developing cervical cancer.
Reproductive variables, tobacco, ethanol, coffee and somatometry as risk factors for ovarian cancer
Authors: Polychronopoulou Argy , Tzonou Anastasia , Hsieh Chung‐Cheng , Trichopoulos Dimitrios , Kaprinis George , Rebelakos Apostolos , Toupadaki Nektaria
Published: February 2007

A hospital‐based case‐control study of ovarian cancer was conducted in Athens from 1989 to 1991. The cases were 189 women, residents of Greater Athens and less than 75 years old, with histologically confirmed common malignant epithelial tumors of the ovary, operated in the 2 major cancer hospitals of the Greater Athens area. Controls were women residents of Greater Athens, less than 75 years old, who had never had cancer or had an ovary removed and who had visited patients hospitalized in the same wards as the ovarian cancer cases at the same time. The data were analyzed by modeling through multiple logistic regression. Statistically significant associations were found with induced menopause without oophorectomy [relative risk (RR) 0.17; 95% confidence interval (C1) 0.04 to 0.72], age at menopause (for an increment of 5 years RR 1.42; C1 1.00 to 2.01), hormone‐replacement therapy (RR 5.73; C1 1.07 to 30.80), parity (RR 0.48; C1 0.24–0.96) and, marginally, age at first birth (for an increment of 5 years RR 1.30; C1 0.99 to 1.70). Non‐significant but previously suggested or biologically plausible associations were noted with use of oral contraceptives (inverse), weight before onset of the disease (positive), and consumption of more than 2 glasses of alcoholic drinks per day (positive). There were no consistent associations with coffee, tobacco, moderate alcohol intake, broad occupational group, induced abortions, or age at menarche.
Diet and ovarian cancer: A case‐control study in greece
Authors: Tzonou Anastasia , Hsieh Chung‐Cheng , Polychronopoulou Argy , Trichopoulos Dimitrios , Kaprinis George , Toupadaki Nektaria , Karakatsani Anna , Trichopoulou Antonia
Published: February 2007

In a hospital‐based case‐control study of common malignant epithelial tumors of the ovary, conducted in Athens (1989‐1991), 189 cases were compared with 200 hospital visitor controls. Personal interviews were conducted in all cases and diet was ascertained through a semi‐quantitative food frequency questionnaire. Nutrient intakes for individuals were estimated by multiplying the nutrient content of a typical portion size for each specified food item by the frequency at which the food was consumed per month and summing these estimates for all food items. Data were analyzed using logistic regression, controlling for non‐dietary confounding factors, total energy intake and, among nutrients, mutual confounding influences. Adjusted odds ratios (rate ratios) for ovarian cancer, associated with particular nutritional variables, were expressed in terms of increments approximately equal to the standard deviations of (the residual of) the respective nutrients, on a daily basis. The adjusted odds ratios (and 95% confidence intervals) were 0.80 (0.65–0.99) for mono‐unsaturated fat and 0.73 (0.61 – 0.87) for crude fiber. No substantial, statistically significant or consistent independent associations were noted for total energy, total protein, saturated fat, polyunsaturated fat, dietary cholesterol, total carbohydrates, sucrose, vitamin C, vitamin A, riboflavin or calcium. These associations, if causal, could explain to some extent the relatively low incidence of ovarian cancer in Greece and other Mediterranean countries as well as the increasing incidence trends noted in these countries during the last few decades.
Prognostic significance of cathepsin‐D expression in node‐positive breast carcinoma: An immunohistochemical study
Authors: Tětu Bernard , Cǒté Chantal , Brisson Sonia , Roberge Nancy , Brisson Jacques , Potvin Diane
Published: February 2007

The prognostic significance of cathepsin‐D expression was evaluated by immunohistochemistry in 638 node‐positive breast carcinomas diagnosed between 1980 and 1986. A minimum of 2.5 years of follow‐up was available for each patient (maximum: 9.5 years). Cathepsin‐D expression was assessed separately both in cancer and in stromal cells using a commercially available polyclonal antibody. While cancer‐cell immunostaining was not associated with prognosis, positive staining of stromal elements was related to shorter metastasis‐free survival. The difference in distant metastasis‐free survival between positive and negative expressors was greatest in the sub‐group of patients submitted to adjuvant chemotherapy, with a hazard ratio for occurrence of distant metastasis of 1.76 by multivariate analysis, but was lowest for those receiving hormone therapy. Cathepsin‐D expression by stromal cells was related to HER‐2/ neu oncoprotein expression, HSP‐27 expression, poor nuclear grade, aneuploidy, and absence of estrogen and progesterone receptors. No association was found with the number of involved lymph nodes, tumor size, age, histologic grade, S‐phase fraction, or vascular invasion. Our study suggests that cathepsin‐D expression by stromal cells (and not by cancer cells) affects the prognosis of breast cancer, that stromal cells probably play a key role in local invasion and metastatic dissemination of the tumor, and that the prognostic significance of cathepsin‐D expression may vary according to the type of adjuvant therapy.
Contrasting effects of 17 β‐estradiol on the growth of human ovarian carcinoma cells in vitro and in vivo
Authors: Langdon Simon P. , Ritchie Alison , Young Karen , Crew A. Jayne , Smyth John F. , Miller William R. , Sweeting Vicky , Bramley Tony , Hillier Stephen , Hawkins Richard A. , Tesdale Ann L.
Published: February 2007

A human ovarian adenocarcinoma cell line (PE04) has been established as a xenograft in nude mice. In vitro, this cell line is estrogen receptor (ER)‐positive and its growth is stimulated by 17 β‐estradiol at concentrations between 10−12 and 10−6 M. When xenografted, PE04 cells remain ER‐positive and also possess progesterone receptors (PR); treatment with 17 β‐estradiol reduces the concentration of ER and increases levels of PR. Growth of the xenograft is reduced in ovariectomized animals while implantation of estrogen pellets also results in growth inhibition. Similar treatment with estrogen does not inhibit the ER‐negative HOX 60 ovarian xenograft, and stimulates growth of the ER‐positive ZR‐75‐1 breast carcinoma xenograft. Serum measurements of 17 β‐estradiol confirm that ovariectomy reduces the level of 17 β‐estradiol while implantation of estrogen pellets results in raised levels of the hormone. Tamoxifen inhibits growth of the PE04 xenograft but not that of the HOX 60 xenograft, consistent with ER status. These results indicate that ER‐positive PE04 ovarian cancer cells are sensitive to 17 β‐estradiol in vivo but that the response may be of a different type from the in vitro response. This lends further support to the concept that ovarian cancer may be hormone‐sensitive and potentially responsive to endocrine therapy.
Involvement of thrombospondin in the adherence of human breast‐adenocarcinoma cells: A possible role in the metastatic process
Authors: Incardona Francesca , Fauvel‐Lafeve Françoise , Legrand Yves , Legrand Chantal , Calvo Fabien
Published: February 2007

The attachment of cancer cells to adhesive molecules, such as laminin (LN) and fibronectin (FN) in the extracellular matrix is a critical step in tumor invasion and metastasis. Recent data have suggested a potential role for thrombospondin (TSP), a 420‐kDa cyto‐adhesive glycoprotein, in the growth and spread of breast cancer. In this study, we have measured the ability of the human breast adenocarcinoma cell line, MDA‐MB‐231, to synthesize TSP and to use this molecule as an adhesion factor. The level of TSP in cells and secreted into the culture medium were determined by an enzyme‐linked immunosorbent assay (ELISA). At pre‐confluence, MDA‐MB‐231 cells were shown to produce a high level of TSP, most of which was retained within the cells. In comparison, FN was almost entirely secreted into the culture medium. An increased secretion of TSP was however measured at low cell density, suggesting that TSP might be required for cell/substratum or cell/cell interactions. As shown by flow cytometry, the cells expressed membrane‐bound TSP as well as unoccupied TSP receptors. 125I‐TSP bound saturably to 1.2 x 106 sites per cell with an apparent dissociation constant of 23 nM. The binding was inhibited by an excess of unlabeled TSP and by heparin, suggesting that the receptor could be a heparian‐sulfate proteoglycan or a sulfatide. TSP promoted attachment but not spreading of MDA‐MB‐231 cells which attached and spread on FN and LN substrates. These results suggest that endogenously synthesized TSP may have a role in the cyto‐adherence of tumor cells during the spread of breast cancer.
Binding properties of monoclonal antibodies recognizing external epitopes of the human MDR1 P‐glycoprotein
Authors: Schinkel Alfred H. , Borst Piet , Smit Jaap J. M. , Wagenaar Els , Dollé Martijn , Arceci Robert J. , Baas Frank , Tsuruo Takashi , Mechetner Eugene B. , Roninson Igor B.
Published: February 2007

Monoclonal antibodies (MAbs) recognizing external epitopes of the human MDRI P‐glycoprotein have been used both for the detection of multidrug‐resistant cells and as specific inhibitors of P‐glycoprotein‐mediated multidrug resistance. Using a panel of recently developed transfected or transgenic cell lines containing variants of the human MDRI and MDR3 P‐glycoproteins, we have compared the specificity and binding properties of the previously isolated MAbs MRK16, HYB‐241, UIC2 and 4E3, and of the newly isolated MAb 7G4. The removal of 1, 2 or all 3 of the N‐glycosylation sites present in the first extracellular loop of MDR1 P‐glycoprotein did not significantly affect the binding of these MAbs. In contrast, a 20 amino acid deletion in the first extracellular loop of MDR1 P‐glycoprotein completely abolished binding of UIC2, whereas the binding of all other MAbs was hardly affected. None of the MAbs tested bound detectably to cell lines containing a high level of the human MDR3 P‐glycoprotein. The differences in the binding specificity between UIC2 and the other tested antibodies parallel the reported functional differences in the ability of these antibodies to inhibit P‐glycoprotein‐mediated drug efflux.
Irradiated fibroblasts protect burkitt lymphoma cells from apoptosis by a mechanism independent of BCL‐2
Authors: Falk Martin H. , Bornkamm Georg W. , Hültner Lothar , Milner Anne , Gregory Christopher D.
Published: February 2007

When cells of fresh Burkitt lymphoma (BL) biopsies are explanted into tissue culture, their survival and growth are greatly dependent on the presence of a feeder layer of irradiated fibroblasts. To investigate the nature of this feeder dependence, we characterized the growth requirements of a panel of Epstein‐Barr Virus (EBV)‐negative and ‐positive BL cell lines in both the absence and the presence of feeder cells in vitro. Four EBV‐negative BL lines and 4 EBV‐positive lines displaying the phenotype of BL cells in vivo required high cell density for proliferation in the absence of feeder cells, but grew out as single‐cell clones when seeded on irradiated human fibroblasts. EBV‐positive BL cell lines which had acquired an activated phenotype similar to that of lymphoblastoid cell lines required much lower cell densities for autonomous proliferation. The EBV‐negative Burkitt lymphoma line BL70 was used as a model to study the feeder‐cell dependence in more detail. BL70 cells grew in the absence of feeder cells only at high cell density and at high FCS concentration. In the presence of feeder cells, BL70 cells became clonogenic even at greatly reduced FCS concentration. A decrease in either cell density or FCS concentration induced apoptosis. Supernatants from feeder cells and from BL70 cells growing autonomously at high cell density were unable to substitute for the survival and growth‐promoting effect of the feeder cells. Protection of Burkitt lymphoma cells from apoptosis by co‐cultivation with irradiated fibroblasts was not mediated by induction of bcl‐2. The system described here may be relevant for the in vivo situation since Burkitt lymphoma cells are protected from c‐MYC induced apoptosis in vivo also by a mechanism which does not involve bcl‐2.
Sodium butyrate induces apoptosis in human colonic tumour cell lines in a p53‐independent pathway: Implications for the possible role of dietary fibre in the prevention of large‐bowel cancer
Authors: Hague A. , Manning A. M. , Hanlon K. A. , Hart D. , Paraskeva C. , Huschtscha L. I.
Published: February 2007

The purpose of this study was to determine whether cultured colonic adenoma and carcinoma cells undergo apoptosis (programmed cell death) in vitro and whether specific growth and dietary factors, thought to be involved in the control of growth and differentiation of human colonic cells, could induce cell death through apoptosis. In cell lines originating from 6 colorectal adenomas and 7 carcinomas, spontaneous apoptosis was observed. Sodium butyrate, a naturally occurring fatty acid, is present in the human large bowel in millimolar amounts as a result of bacterial fermentation of dietary fibre. Sodium butyrate, at physiological concentrations, induced apoptosis in 2 adenoma cell lines, RG/C2 and AA/C1, and in the carcinoma cell line PC/JW/F1. In contrast, transforming growth factor β1, which is thought to have an important role in the control of growth in colonic epithelium, did not induce apoptosis. Neither RG/C2 nor PC/JW/F1 contain wild‐type p53, therefore this tumour‐suppressor gene is not required to mediate signals for the induction of apoptosis in colonic tumour cells. Our studies report the induction of apoptosis in colonic tumour cells by the naturally occurring fatty acid sodium butyrate. Since sodium butyrate is produced by bacterial fermentation of dietary fibre, the observation that this fatty acid can induce apoptosis could, in part, explain why a high‐fibre diet appears to be protective against colon cancer. Escape from the induction of programmed cell death may be an important event in colorectal carcinogenesis.