bluuebunny/crossref_metadata_2025_split huggingface dataset:
Physicochemical purification and immunological characteristics of ductal carcinoma antigen
Authors: Papsidero Lawrence D. , Johnson Edward A. 
Published: February 2007

AbstractDuctal carcinoma antigen (DCA), as recognized by monoclonal antibody (MAb) F36/22, was purified in high yield and to homogeneity from malignant effusions by means of physicochemical techniques. Fractionation procedures were monitored by immunoenzymometric assays. Preparations purified over 2,000‐fold were obtained through acid‐extraction, lectin‐chromatographies and gel filtration steps. Purified antigen demonstrated a single component upon electrophoretic examination. This material had a high molecular weight and high immunoreactivity. Neuaminidase treatments failed to perturb the antigenicity of the component, indicating an absence of sialic acid residues at the antibody‐combining site. Further, extensive proteolytic digestion effected the release of heterogeneous glycopeptides which retained immunologic activity, suggesting the presence of carbohydrate at the active site. Immunologically, DCA was compared with other tumor‐associated mucin‐like gly‐coproteins which have been detected in the circulation of patients. Results indicated no cross‐reactivity between DCA and other mucins, including CA 19–9 and CA‐125. Further, no antigenic relationship was noted for purified carcinoembryonic antigen (CEA), also a heavily‐glycosylated structure. These data thus suggest that immunological monitoring of disease may be approached using a selected panel of antigenically distinct reagents.
Biochemical regulation of adenylate cyclase in murine melanoma clones with different metastatic properties
Authors: Sheppard J. R. , Lester Bruce , Doll John , Buscarino Charles , Gonzales Elisa , Corwin Steven , Greig Russell , Poste George 
Published: February 2007

AbstractThe regulation of adenylate cyclase in murine melanoma tumor cell clones with different metastatic capacities has been studied in intact cells and isolated membrane preparations. Analysis of the responses of intact cells from a number of B16 melanoma clones revealed that treatment with melanocyte‐stimulating hormone (MSH) or the diterpene, forskolin, produced significantly greater accumulation of intracellular cyclic adenosine 3′,5′ monophosphate (cAMP) in strongly metastatic clones than in weakly metastatic tumor cell clones. In contrast, in isolated membranes from the same panel of clones, the extent of activation by forskolin but not by MSH correlated with metastatic capacity. Sodium fluoride and 5′‐guanyl‐ß‐γ‐imidodiphosphate [Gpp(NH)p] also stimulated adenylate cyclase in isolated membranes but the extent of activation did not correlate with the metastatic behavior of the donor cells. A combination of forskolin and Gpp(NH)p proved to be a sensitive prospective indicator for identifying differences in the metastatic capabilities of individual B16 melanoma clones. Adenylate cyclase in membrane preparations from strongly metastatic B16 clones displayed synergistic activation but stimulation of the enzyme from weakly metastatic clones was less than additive. To test the generality of these findings, similar investigations were performed on B16‐BL6 melanoma cells, a highly invasive subline of the B16 melanoma, and the K1735, an ultraviolet‐light‐induced murine melanoma arising in a different mouse strain (C3H). Consistent with their high metastatic potential, clones derived from the B16‐BL6 melanoma displayed elevated levels of hormon‐ally‐stimulated adenylate cyclase, thereby confirming, for this tumor system, a close association between hormonal responsiveness and metastatic capacity. In contrast, K1735 melanoma cell clones exhibited significant interclonal variation in adenylate cyclase activity and metastatic performance, but no consistent relationship between the two traits was detected. Differences in the regulation and/or the intrinsic catalytic capacity of adenylate cyclase may account, at least in part, for the variation in hormonal responsiveness observed among B16 clones with distinct metastatic properties and suggest that cAMP‐dependent molecular processes may be required for the expression of B16 melanoma experimental metastatic potential. The failure to detect a similar association between cAMP metabolism and metastatic performance in the K1735 melanoma cells indicates that this molecular process is not an invariant feature of metastatic tumor cells and suggests that metastatic competence in tumor cells arising from a common cell lineage involves diverse phenotypic aberrations.
Characterization of a tumorigenic murine T‐lymphoid‐cell line spontaneously derived from an IL‐2‐dependent T‐cell line
Authors: Mann Varda , Szyf Moshe , Razin Aharon , Chriqui‐Zeira Evelyne , Kedar Eli 
Published: February 2007

AbstractThe establishment of IL‐2‐independent T‐cell lines spontaneously derived from long‐term IL‐2‐dependent cytotoxic T‐cell lines is described. Two lines (cloned and uncloned) studied in detail have shown the following characteristics: (1) Permanent loss of IL‐2 dependence. (2) Partial or complete loss of both cytotoxic activity and the IL‐2 receptor. (3) Increased expression of T‐cell membrane markers (Thy 1.2, Lyt 1.2) compared with the parental line. (4) Lower level of DNA methylation than in freshly obtained lymphoid cells. (5) Different karyotypic pattern from the parental IL‐2‐dependent line, with a mean number of 39–40 chromosomes and a resemblance to T leukemic lines. (6) Leukemia caused in normal syngeneic C57BL/6 mice by the uncloned line, in contrast to the cloned IL‐2‐independent line or the parental dependent line. Unlike established leukemic lines, however, the independent line gave rise to tumors which regressed in some mice within a few days of their appearance. These findings suggest that T‐cell lines maintained with IL‐2 for prolonged periods of time (> 3 months) can undergo transformation and, therefore, should not be utilized for immunotherapeutic purposes.
Separation, phenotyping and limiting dilution analysis of T‐lymphocytes infiltrating human solid tumors
Authors: Whiteside Theresa L. , Miescher Sylvia , Hurlimann Jean , Moretta Lorenzo , Fliedner Vladimir Von 
Published: February 2007

AbstractTumor‐infiltrating lymphocytes (TIL) were obtained by a combination of mechanical release and enzymatic disaggregation from 35 human solid tumors. The number of lymphocytes in TIL‐enriched suspensions varied from 1 × 104to 7.6 × 106per wet gram of tumor. The TIL preparations separated by differential centrifugation on Ficoll‐Hypaque gradients contained 10–95% of TII+cells (mean 50%), and tumor cells accounted for the other major cellular component. Macrophages, NK cells, B cells and granulocytes were infrequently seen. Morphologically, TIL‐T were small non‐activated cells. They expressed the TII and T3 antigens but not the receptor for IL‐2 (IL‐2R) or HLA‐DR antigens as determined by double immunofluorescence staining. Rare TII+/IL‐2R+cells were recovered only from colon and lung carcinomas. The mean T4/T8 ratio in 12 TIL preparations was 1.1 ± 0.8. Immunohistology with monoclonal antibodies (MAbs) performed in 31/35 tumors confirmed that the TII+cells infiltrating solid tumors rarely expressed the IL‐2R and that the cell content of suspensions enriched in TIL was comparable to that determinedin situ. The recovered TIL were cloned in a microculture system that permits proliferation of nearly all normal peripheral blood T lymphocytes (PBL‐T). Under these culture conditions, frequencies of the proliferating T lymphocyte precursors (PTL‐P) were depressed in both the TIL preparations (< 0.01 to 0.39) and patients' PBL‐T (0.05 to 0.5). These low frequencies of PTL‐P were seen in patients with all tumor types, both primary and metastatic.
Influence of growth phase, nutrition and hypoxia on heterogeneity of cellular buoyant densities in in vitro tumor model systems
Authors: Luk Catherine K. , Sutherland Robert M. 
Published: February 2007

AbstractEMT6/Ro multicellular spheroids were sequentially dissociated into outer, middle and inner layers, and the buoyant densities of these subpopulations were compared to aerobic or exponential or plateau‐phase monolayers by isopycnic density centrifugation using Percoll as the gradient medium. Spheroids were more heterogeneous in buoyant density distributions than monolayer cultures. The outer‐layer cells of spheroids and fed plateau monolayers peaked at a similar density; the majority of middle‐layer cells banded close to unfed plateau and exponential hypoxic monolayers, while most inner‐layer cells banded where fed or unfed plateau hypoxic monolayer peaked in density. Our data suggest that metabolic heterogeneity due to growth phase, together with altered cellular microenvironment brought about by differences in oxygenation and external nutrient supplies between spheroids and monolayers, can be manifested in one biophysical parameter such as buoyant density.
Ca2+ and calmodulin are involved in the processes conferring stability to DNA in proliferating neoplastic cells
Authors: Lönn Ulf , Lönn Sigrid 
Published: February 2007

AbstractWe have examined, in proliferating neoplastic cells, the effect on DNA of EGTA (a chelator of Ca2+) and W7 (an inhibitor of calmodulin). The treatment results in release of single‐stranded DNA fragments (2‐10 kb) from pre‐labelled HMW DNA. When DNA from synchronized neoplastic cells in S phase is examined, almost all pre‐labelled DNA appears as short fragments. However, fragmentation does not occur in growtharrested cells or in normal cells. Furthermore, fragmentation can be prevented by incubating cells in excessive amounts of Ca2+. Hence Ca2+ and the Ca2+‐binding protein calmodulin are involved in the processes conferring stability to DNA in proliferating neoplastic cells.
Biochemical characterization and biologic activities of 82‐and 86‐kDa tumor antigens isolated from a methylcholanthrene‐induced sarcoma, CII‐7
Authors: Dubois Garrett C. , Law Lloyd W. 
Published: February 2007

AbstractTwo tumor‐specific antigens, with molecular weights of approximately 82 and 86 kDa, have been isolated and purified to apparent homogeneity from the methylcholanthrene‐induced sarcoma, CII‐7. The method of purification used was essentially that previously employed for the isolation of the 82‐ and 86‐kDa antigens from the Meth A sarcoma and the 86‐kDa antigen from mKSA sarcoma. Cytosolic fractions were subjected to hexylamine agarose chromatography, Sepharose S‐300 filtration and hydroxylapatite chromatography. A final step, HPLC‐DEAE chromatography, was necessary for the purification of the 82‐kDa protein. Both isolated antigens retained their specific immunogenicity for CII‐7 as determined by in vivo tumor rejection assays, and failed to influence the growth of other syngeneic sarcomas, CI‐4, CII‐10 and mKSA, which have their own unique TATA. The 82‐and 86‐kDa antigens appear to be distinct proteins that are well conserved in nature and may represent members of distinct families of TATA.
Trisomy and tetrasomy for long arm of chromosome 1 in near‐diploid human endometrial adenocarcinomas
Authors: Couturier J. , Vielh P. H. , Salmon R. , Dutrillaux B. 
Published: February 2007

AbstractKaryotypic analysis by R‐banding after short‐term culture, carried out on 7 cases of human endometrial adenocarcinoma, showed in 4 of these a trisomy or a tetrasomy for the long arm of chromosome I. In the 4 cases, these imbalances were due to rearrangements involving centromeric or para‐centromeric breakpoints: 46, XX,−16, + der(1q16p) t(1;16)(1p16q;1q16p); 46, XX,−21, + der(1q21q) t(1;21)(1p21p;1q21q);46, XX,−21, + der(21) t(1;21)(q11;p13); 48, XX, +2, + i(1q). Two other cases showed only a numerical aberration: 47, XX, + 10 and 47, XX, + 12. In the last case, only cells with apparently normal karyotype were seen. In the 4 cases with an anomaly of chromosome I, two normal I chromosomes coexisted with abnormal elements. This shows that the rearrangement very likely occurred in G2 phase of the cell cycle.
Incidence of soft‐tissue cancers in blacks and whites in New York State
Authors: Polednak Anthony P. 
Published: February 2007

AbstractIncidence rates for several histologic types of soft‐tissue cancers were compared between black and white residents of New York State during 1976–81, using data from the population‐based New York State Cancer Registry. Incidence rates for leiomyosarcoma, neurofibrosarcoma and malignant neurolemmoma were higher for blacks than for whites in almost all age groups. Black‐white differences in malignant mesenchymoma, while not statistically significant, were similar to those from other population‐based studies. There was no evidence for black‐white differences in certain other histologic types (e.g., blood‐vessel cancers, lymphangiosarcoma). Black‐white differences in leiomyosarcoma included higher rates for the uterus in black than in white females, and higher rates for the stomach in blacks of both sexes. Possible explanations for these differences in soft‐tissue cancer incidence were discussed, along with comparisons with limited data on black populations in Africa.
Measurement of the survival of human tumor cells after implantation in athymic nude mice
Authors: Romijn J. C. , Verkoelen C. F. , Schroeder F. H. 
Published: February 2007

AbstractA method has been developed to determine the survival of human tumor cells after implantation in athymic nude mice. The method involves the labelling of cells of the prostatic cancer cell line PC‐3 with tritiated thymidine after attachment of the cells to Millipore filter disks. The amount of radioactive label incorporated in the cells remained constant for at least 48 hr during in vitro incubation. After s.c. implantation of the filter disks in nude mice, however, the fraction of surviving cells, reflected by the amount of radioactivity persisting on the filters, rapidly decreased with time. Only a relatively small fraction (approx. 10%) of the cells survived for more than 24 hr under these conditions. Pretreatment of the mice with cyclophosphamide (100 mg/kg, 24 hr prior to implantation) resulted in a 2‐fold increase of tumor‐cell survival. Likewise, the frequency of tumor takes after injection of PC‐3 cells was enhanced following cyclophosphamide pretreatment. These results indicate that immune defense mechanisms might be partly (but not completely) responsible for tumor‐cell rejection in nude mice. The technique described here might be a valuable tool for the rapid evaluation of possible effects of various types of pretreatment of the host animal on tumor cell survival and, thereby, on tumor growth.
Quantification and characterization of high‐affinity membrane receptors for tumor necrosis factor on human leukemic cell lines
Authors: Scheurich Peter , Ücer Ugur , Krönke Martin , Pfizenmaier Klaus 
Published: February 2007

AbstractThe expression of specific membrane receptors for TNF‐aipha was determined on various human leukemic cell lines differing in their sensitivity to the growth‐inhibitory activity of TNF‐alpha. Binding studies with 125Mabelled TNF‐alpha indicated specific binding in 8/10 cell lines with approximately 10‐fold differences in the quantity of TNF‐alpha bound by these distinct cell lines. Scatchard analyses of TNF‐binding revealed the existence of high‐affinity membrane receptors (Kd 1.5 × 10−10 M) and approximately 3,000 binding sites/cell on both U937 and K562, representing 2 cell lines with high and low TNF sensitivity, respectively. Disuccin‐imidyl‐suberate cross‐linking of receptor‐bound 125I‐TNF‐alpha and SDS‐PAGE of membrane preparations of either U937 or K562 cells suggest a single receptor protein with an apparent molecular weight of 76 kDa. Comparison of the TNF‐alpha binding capacity versus in vitro growth inhibition provides evidence that sensitivity to TNF‐alpha is determined both at the level of receptor expression and at a post‐receptor level. IFN‐gamma strongly enhanced the TNF‐alpha‐mediated growth inhibition of 3 sensitive cell lines, but had no effect on 7 other leukemic cell lines with little or no TNF sensitivity. No correlation was found between this enhancement of TNF sensitivity and the IFN‐gamma‐mediated increase in TNF‐cell membrane receptors, suggesting that IFN‐gamma predominantly exerts its synergistic effect distal to TNF‐binding.
Requirement for the continual presence of lipopolysaccharide for production of tumor necrosis factor by thioglycollate‐induced peritoneal murine macrophages
Authors: Gifford George E. , Lohmann‐Matthes Marie‐Luise 
Published: February 2007

AbstractThis work demonstrates the need for the continued presence of lipopolysaccharide (LPS) for tumor necrosis factor (TNF) production by thioglycollate‐induced peritoneal macrophages. Removal of LPS at any time resulted in the abrupt cessation of further TNF production. The readdition of LPS resulted in further production of TNF but the yield was limited to the amount that would have been produced had the LPS not been removed.
Resistance of line 63 chickens to reticuloendotheliosis‐virus‐induced bursa‐associated lymphomas
Authors: Fadly Aly M. , Witter Richard L. 
Published: February 2007

AbstractChickens of lines 63 and 1515 × 71 were inoculated with the chick syncytial strain of reticuloendotheliosis virus (REV) or with the Rous‐associated virus‐1 of avian leukosis virus (ALV) at hatching. At 4, 10, 16, and 36 weeks post inoculation (PI), chickens were tested for REV‐and ALV‐induced viremia and antibody. The incidence of REV‐or ALV‐induced bursa‐associated lymphomas in line 63 chickens was compared with that in line 1515 × 71 chickens. Inoculation of REV at hatching resulted in immunological tolerance to the virus in line 63 but not in line 1515 × 71 chickens. Between 70% and 100% of line 63 chickens remained viremic and lacked REV antibody throughout the experimental period of 36 weeks. In contrast, ALV‐inoculated chickens of both lines had antibody by 16 weeks PI. The frequencies of REV‐and ALV‐induced bursa‐associated lymphomas in line 63 chickens were significantly lower than in line 1515 × 71 chickens. Further, the incidence of bursa‐associated lymphomas induced by REV in line 1515 × 71 chickens was significantly lower than that induced by ALV. These results suggest that: (1) the genetic constitution of the host may influence the immunological response to REV infection; (2) chickens resistant to ALV‐induced bursa‐associated lymphomas are equally resistant to such lymphomas induced by another unrelated avian retrovirus, REV; and (3) ALV is a more potent inducer of bursa‐associated lymphomas than REV.
Differentiation antigens in fetal human pancreas. Reexpression in cancer
Authors: Escribano Maria Juana , Cordier Jocelyne , Nap Marius , Kate Fiebo J. W. Ten , Burtin Pierre 
Published: February 2007

AbstractAn antiserum was raised against pancreatic extracts obtained from human fetuses under 5 months of gestational age. After absorption with adult tissues, this antiserum specifically recognized antigens located in the cytoplasm of fetal pancreatic acini. All of the examined pancreatic tissues, ranging from 3 to 5 months of gestational age, showed a strong positive reaction of most of the acinar cells. The number of stained acini and the staining intensity gradually decreased from 5 months onwards and by the 7th–8th month only a few cells remained positive. Adult pancreas was completely negative as were a variety of normal adult and fetal tissues. This antiserum also reacted with tumor structures in 18/18 pancreatic adenocarcinomas as well as with pancreatic acini in the vicinity of tumor. Primary carcinomas of the liver, large bowel, stomach, breast, urinary bladder, lung and other localizations did not react with this antiserum. In some cases of chronic pancreatitis (3/12) a reaction was observed in a few acinar cells. Immunoblot assay after polyacrylamide electrophoresis revealed, in both fetuses and tumors, two main antigens of approximately 60 kDa and 110 kDa relative molecular weight. Several minor components were also observed.
Risk of colorectal cancer in adenoma‐bearing individuals within a defined population
Authors: Eide Tor J. 
Published: February 2007

AbstractAssuming that all colorectal cancers develop from preexisting adenomas, the annual conversion rate, defined as the number of cancers occurring each year as a percentage of all adenoma‐bearing individuals, was determined. The number of adenoma‐bearing individuals in the living population of northern Norway was estimated in each cohort for the period 1974–76 by determining the prevalence of colorectal adenomas in an autopsy population of 271 consecutive cases, representative of the population of the area with regard to underlying causes of death. During the 10‐year period 1974–1983 a total of 656 colorectal cancers were recorded among an estimated number of 26,419 adenoma‐bearing individuals aged over 35 years. The annual conversion rate was found to be 0.25%, indicating that an average adenoma‐bearing individual is only at a moderate risk of colorectal cancer. The annual conversion rates for individuals having large adenomas, or adenomas with villous structures, or severe dyspla‐ sia were roughly estimated to be 3%, 17% and 37% respectively, assuming that colorectal cancer develops from one of these sub‐groups of adenomas only.
Evolution in the structure and distribution of 4F2‐antigen from the oncofetal to the adult phenotype of human fibroblasts
Authors: Azzarone B. , Eid P. , Malpiece Y. , Andeol Y. , Fauci A. S. , Suarez H. 
Published: February 2007

AbstractThe monoclonal antibody (MAb) 4F2 defines an oncofetal antigen in human fibroblastic cells. Two‐dimensional electrophoretic analysis reveals that tumor cell lines from mesenchymal tissues co‐express two or more heavy‐chain molecular variants of the antigen whereas the light subunit (41 kDa) is not affected. Among normal cells, only embryonic and newborn fibroblasts (from donors up to 20 days after birth) clearly co‐express two distinct molecular forms of the heavy chain with MW of 85 and 75 kDa, respectively. Cells derived from 3‐month‐old donors express detectable amounts of the 85 kDA but only faint traces of the 75 kDa subunit, while fibroblastic cells derived from donors older than 3 months seem to express only the 85 kDa subunit. Immunofluorescence analysis performed on adherent living cells shows that, in the first months after birth, there is a gradual evolution from the oncofetal to the adult phenotype also in the cell distribution of the 4F2. This evolution is reflected by a progressive disappearance of the 4F2 antigen from the cell membrane becoming, in adult normal cells, inaccessible to anti‐4F2 MAb. The existence of different molecular forms and different membrane positions of the 4F2 antigen could facilitate surveillance of morphological and structural changes in the evolution of human fibroblastic cells during the developmental process and neoplastic transformation.
Case‐control study on colorectal cancer and diet in marseilles
Authors: Macquart‐Moulin Geneviève , Riboli Elio , Cornée Jacqueline , Charnay Bernadette , Berthezene Patrice , Day Nicholas 
Published: February 2007

AbstractA case‐control study of cancer of the colon and rectum was conducted in the Marseilles region of southern France. Cases (399) and a corresponding number of controls, matched for age and sex, were included, the controls being selected from patients undergoing functional re‐education for injuries or trauma which reduced their mobility. A dietary history questionnaire was used to determine the usual eating habits during the year preceding diagnosis for cases, or preceding interview for controls. The cases reported lower consumption of vegetables and oil than controls, but no differences were seen in the consumption of meat, bread, eggs or butter. The intake of several nutrients, particularly vitamins B2, B6, C, potassium, iron, magnesium and vegetable fibre, was lower among cases. However, when all these nutrients were analysed jointly and adjusted one for the other, only potassium retained a significant effect. This may be due to the high degree of colinearity between the estimated intake of many nutrients. No association was seen with fat or fibres from cereals.