bluuebunny/crossref_metadata_2025_split huggingface dataset:
The ability of normal mouse cells to reduce the malignant potential of transformed mouse bladder epithelial cells depends on their somatic origin
Authors: Cowell John K. , Franks L. M. 
Published: February 2007

AbstractSomatic cell hybrids have been made between a transformed mouse bladder carcinoma cell line and normal mouse bladder epithelium and mesenchyme. In the epithelial tumour/mesenchyme hybrids the malignant phenotype was expressed dominantly whereas in the carcinoma/normal epithelium hybrids the malignant potential was greatly reduced. In both cases the dominant in vitro and in vivo phenotype was that of the normal parental cells. All hybrid tumours were first palpable after 4–7 days, demonstrating that the tumours had not arisen as a result of in vivo selection of a sub‐population of tumorigenic cells. Chromosome analysis showed that the carcinoma/normal epithelium hybrids were all in the hypertetraploid range but the large variation in the karyotypic profile of each hybrid made it impossible to implicate any specific chromosomes in the control of expression of the malignant phenotype. During normal development in bladder epithelium, terminal differentiation is associated with tetraploid formation by cell fusion. The reduction in malignancy of the carcinoma/normal epithelium hybrids may perhaps be due to the expression of genes associated with normal terminal differentiation after cell fusion and tetraploid formation. This is also supported by the more differentiated phenotype of the hybrid tumours. Of the 10 mesenchyme/epithelium hybrids analysed cytotogenetically, four were in the hypertetraploid range from which little meaningful data could be obtained about specific chromosome losses. Chromosome analysis of the cells from the near‐tetraploid hybrids showed only minor differences from what might have been expected from the input of the two parents; these differences appeared to be due to random chromosome loss. The maximum number of chromosomes lost from any of the hybrids was five, although one, two or three was more usual. The only consistent chromosome loss was of a single copy of chromosome 4, which in two of the hybrids represented the only chromosome change. The possibility that this loss might facilitate re‐expression of the malignant phenotype is discussed.
Influence of 12‐o‐tetradecanoylphorbol‐13‐acetate (TPA) on the susceptibility of K562 to natural cytotoxicity: Evidence for clonal variation in differentiation‐induced changes of lytic sensitivity
Authors: Kimber Ian , Moore Michael , Harrison Christine J. 
Published: February 2007

AbstractThe effect of 12‐O‐tetradecanoylphorbol‐13‐acetate (TPA) on the sensitivity to NK cell‐mediated lysis of two cloned populations of K562 which exhibit marked and stable differences in their susceptibility to natural cytotoxicity has been examined. Culture in medium supplemented with TPA concentrations of 1 ng/ml or more invariably caused a decrease in the susceptibility of the sensitive clone E10/P2, whereas treatment of the relatively resistant clone F9/P2 with TPA under identical conditions caused a significant increase in susceptibility to natural cytotoxicity. In both cases the change in susceptibility occurred within 1 day of culture in TPA and was rapidly reversible following removal of the inducing agent. The changes in resistance to natural cytotoxicity induced by TPA were independent of variations in osmotic fragility and were not attributable to alterations in NK cell binding capacity as determined by cold competition analysis. In contrast to the effect of TPA, exposure of E10/P2 and F9/P2 to interferon (IFN) caused a reduction in sensitivity to natural cytotoxicity of both populations which was associated with a decreased capacity to compete for lysis of labelled target cells. These data suggest that the effects of differentiating agents on target susceptibility to NK cell lysis are variable and that responses to TPA are clonally distributed within cell populations.
Prevalence of possible adult t‐cell leukemia virus‐carriers among volunteer blood donors in Japan: A nation‐wide study
Authors: Maeda Yoshiaki , Furukawa Michiyo , Takehara Yuhei , Yoshimura Keiji , Miyamoto Kanji , Matsuura Takao , Morishima Yasuo , Tajima Kazuo , Okochi Kazuo , Hinuma Yorio 
Published: February 2007

AbstractA nation‐wide survey of carriers of adult T‐cell leukemia virus (ATLV) detected as anti‐ATLA (ATLV‐associated antigens) in volunteer blood donors was made in Japan. A total of 200 sera from donors between 40 and 64 years of age, collected in each of 64 blood centers located in eight districts, were tested for anti‐ATLA by an indirect immunofluorescence test. The highest rate (8%) of seropositive donors was found in Kyushu and lower rates of 0.3 to 1.2% in other districts. However, the positive rate varied considerably in different localities even within districts with a high or low seropositive incidence. Further studies of all the donors (16 to 64 years old) in eight centers in Kyushu demonstrated two facts: (1) that the frequency of seropositive donors increased with age, and (2) that four centers in this district showed distinctly high incidences of seropositive donors, while the other four centers showed low incidences. The seropositive rate among all donors was estimated to be about 3% in Kyushu and 0.08 to 0.3% in all other districts.
Immunohistochemical localization of Y hapten and the structurally related H type‐2 blood‐group antigen on large‐bowel tumours and normal adult tissues
Authors: Brown A. , Ellis I. O. , Embleton M. J. , Baldwin R. W. , Turner D. R. , Hardcastle J. D. 
Published: February 2007

AbstractThe monoclonal antibody C14/1/46/10 which defines the Y hapten carbohydrate antigen (Brown et a., 1983) was shown, by the indirect immunoperoxidase technique, to stain tissue sections of 96% of colo‐rectal adenocar‐cinomas and 100% of colo‐rectal adenomas. In contrast, a monoclonal antibody defining the related H type‐2 blood‐group antigen was found to stain 86% of adenocarcinomas and 32% of adenomas. In adenocarcinomas the percentage of cells stained for both antigens was, on average, greater in group O than in group A patients. In adenomas a focal pattern of expression was observed, for both Y hapten and H type‐2 antigen, that was characteristic of group A but not group O adenocarcinomas. In the normal mucosa of the distal colon, whilst H type‐2 antigen was absent, Y hapten was found in the immature cells of the crypt bases. A comparison of the cellular phenotypes present in adenocarcinomas, adenomas and normal mucosa of the distal colon supports the adenoma‐carcinoma sequence hypothesis for the genesis of colo‐rectal carcinomas. In normal adult tissues Y hapten was predominantly found on epithelial cells whilst nervous tissues, muscles and connective tissues were negative. The expression of Y hapten in several positive tissues was dependent upon secretor status. A comparison of the expression of Y hapten and H type 2 antigen on normal adult tissues revealed that all of the permutations of expression of these two structually related antigens were possible.
Preparation of four daunomycin‐monoclonal antibody 79IT/36 conjugates with anti‐tumour activity
Authors: Gallego J. , Price M. R. , Baldwin R. W. 
Published: February 2007

AbstractAs an approach to developing more specific anti‐tumour therapeutic agents, daunomycin has been covalently linked to the human tumour localizing, murine monoclonal antibody 79IT/36. Four procedures for coupling drug to antibody were investigated. The sugar amino group of daunomycin was modified by reaction with succinic anhydride or cis aconitic anhydride and these derivatives were linked to antibody, a carbodiimide reagent being used to produce stable peptide bonding. Alternatively, 14‐bromo daunomycin was linked directly to antibody or antibody containing free thiol groups introduced by means of the heterobifunctional reagent SPDP [N‐succinimidyl‐3 (2‐py‐ridyldithio) propionate] thus producing a thioether linkage. Each of the conjugates, with drug‐antibody ratios of 3 to 4:1, retained a proportion of drug activity although the succinic anhydride derivative was the least cytotoxic. The three other conjugates specifically bound to tumour cells expressing the 79IT/36 antibody defined antigen. In shorterm assays in which tumour cells were briefly exposed to conjugates and then washed to remove non‐bound conjugate, it was determined that the conjugate with the cis aconityl linkage displayed the greatest selective cytotoxicity against tumour cells reactive with the 79IT/36 antibody. These studies illustrate the feasibility of preparing chemically defined drug‐antibody conjugates retaining cytotoxicity and selectivity of action against tumour cells.
Abnormal properties of skin fibroblasts from patients with breast cancer
Authors: Azzarone B. , Mareel M. , Billard C. , Scemama P. , Chaponnier C. , Macieira‐Coelho A. 
Published: February 2007

AbstractThe growth properties of fibroblasts from the thoracic skin of patients with mammary cancers were compared to those of fibroblastic cultures from patients with benign lesions or having undergone surgery for non‐neoplastic diseases. As expected, an inverse correlation was found between the doubling potential of fibroblasts in vitro and the donor's age for cells from patients with benign lesions; however no correlation, was found with cultures from cancer patients. Moreover, the latter group responded in an abnormal way to three biological parameters: anchorage dependence, colony formation on monolayers of normal human epithelial cells and saturation densities in overcrowded culture conditions. Skin fibroblasts from one patient with a benign lesion, whose mother had developed a breast cancer, displayed all the abnormal growth properties. Periodic controls of this patient resulted in the early detection of a carcinoma 3 years after the first operation for a benign microcystic lesion. Finally, we found that multiple subcultivations in overcrowded culture conditions cause the selection of a fibroblastic cell subset with greater growth potential which, in the cell strain tested, could invade foreigh tissus in vitro.
Selective effects of insulin and hydrocortisone on colony formation and chemosensitivity of human tumors in soft agar
Authors: Kern David H. , Chien Fu‐Wen , Morton Donald L. 
Published: February 2007

AbstractBecause low plating efficiencies of most human cancers severely limit the number of successful chemosensitivity tests that can be performed, we studied the growth‐enhancing effects of insulin and hydrocortisone on a variety of solid tumors. Colony formation in soft agar was significantly increased in 23/49 (47%) tumors treated with 3 U/ml insulin, whereas fewer colonies were observed in 7 (14%). These effects were highly selective for tumor type. Colony growth for ovarian, lung, and colon carcinomas increased by 123%, 37% and 28%, respectively. In contrast, insulin inhibited the growth of melanoma, kidney, and breast tumors. Hydrocortisone at 0.05 μg/ml increased colony numbers in 23/45 (51%) tumors, while in 7 (16%) colony numbers were decreased. Growth of ovarian, lung, breast, and kidney carcinomas was increased by 136%, 126%, 78% and 69%, respectively, whereas melanomas, sarcomas, and colon tumors were inhibited by hydrocortisone. In vitro chemosensitivities were relatively unchanged by the hormones. In 168 (134 paired) drug/tumor tests, sensitivity to standard antineoplastic drugs in the presence or absence of hormones was concordant 82% of the time (correlation coefficient, 0.71). However, in 20 tests (15%), significant enhancement of chemosensitivity was observed. We concluded that cloning efficiencies of many common human tumor types can be improved with hormones, and that these growth‐enhancing effects are selective for tumor type.
Inhibition of tumour‐induced angiogenesis by systemically administered protamine sulphate
Authors: Majewski Slsawomir , Kamińki Marek J. , Szmurlo Andrzej , Kamińska Grazyna , Malejczyk Jacek 
Published: February 2007

AbstractSystemic administration of protamine sulphate significantly decreased the intensity of angiogenesis induced in X‐ray immunosuppressed (BALB/c × DBA/2W) F1 mice by either HEp‐2 (human larynx carcinoma) cells or semisyngeneic splenocytes injected intradermally. In vitro experiments have shown that protamine sulphate markedly decreases the proliferation of human endothelial cells as assessed by 3H‐TdR incorporation assay. In contrast, the proliferation of HEp‐2 cells was not affected, and only slight inhibition of normal human fibroblasts could be demonstrated. Heparin abolished the inhibitory effect of protamine sulphate, both in vivo and in vitro. These results suggest that the observed inhibitory effect of protamine sulphate on angiogenesis in vivo may be at least partially due to the interaction of this compound with endothelial cells.
A rat yolk‐sac antigen defined by monoclonal antibodies
Authors: van Hove L. , Sobis H. , Lu Y. L. , Vandeputte M. 
Published: February 2007

AbstractThe distribution of a rat yolk‐sac antigen (Rat YSA‐1) as defined by a monoclonal antibody raised against rat yolksac carcinoma cells is described. The antigen is present on rat yolk‐sac carcinomas, on visceral yolk‐sac endoderm and on embryonal endoderm of 9‐day‐old embryos. It is not present on a variety of rat tumors other than yolk‐sac carcinomas and not detectable on pre‐implantation embryos, inner cell mass and fetal endoderm. Rat YSA‐1 differs from alpha‐fetoprotein and Forssman antigen and is species‐specific. In adult rats the only cells displaying this antigen are the spermatozoa and certain cells of the spermatogenic lineage.
Analysis of a human osteogenic sarcoma antigen and its expression on various human tumour cell lines
Authors: Campbell D. G. , Price M. R. , Baldwin R. W. 
Published: February 2007

AbstractThe murine monoclonal antibody 79IT/36 cross‐reacts with cells other than the immunizing osteogenic sarcoma cell line 79IT, upon which the 79IT/36‐defined epitope is expressed on a protein of apparent molecular weight 72,000. An investigation was performed to determine whether the epitope occurred on similar molecules on other cell lines. Radiolabelled immunoprecipitates, prepared with the 79IT/36 antibody, from three osteogenic sarcoma cell lines (2 OS, 788T and 278T), the prostate carcinoma EB33 and the colon carcinoma HcLo each contained a protein with a molecular weight of 72,000 as the major constituent, together with, in some cases, material of lower molecular weight. This heterogeneity was shown by neuraminidase treatment of the immune precipitates to be due to variations in sialic acid content of the antigens since, in five of the six cell lines tested, such treatment produced homogeneous material of apparent molecular weight 55,000. Chymotrypsin treatment of the immune precipitates produced in each instance a major polyypeptide of molecular weight 47,000 which displayed no microheterogeneity. Immunoadsorbent‐purified antigen from 79IT cells was shown to bind strongly to Sepharose‐wheat‐germ agglutinin and less to Sepharose‐concanavalin A, confirming the glycoprotein nature of this antigen. These studies demonstrate that molecules expressing the 79IT/36‐defined epitopes on different tumour cell lines are glycoproteins which display heterogeneity with respect to apparent molecular weight that is attributable to varying degrees of sialylation. No apparent differences were detected in the polypeptide “backbone” of these antigenic molecules.
The isolation and characterization of colorectal epithelial cell lines at different stages in malignant transformation from familial polyposis coli patients
Authors: Paraskeva Christos , Buckle Brenda G. , Sheer Denise , Wigley Caroline B. 
Published: February 2007

AbstractThe genetic disease familial polyposis coli (hereditary adenomatosis of the colon and rectum) provides an excellent model for the study of tumour progression in the large bowel. We have isolated and characterized four epithelial cell lines from colorectal tumours from polyposis coli patients. These cell lines are grown on collagen‐coated Petri dishes in the presence of mouse 3T3 feeder cells in medium containing 20% foetal bovine serum. Of these cell lines three were isolated from premalignant adenomas and one from an adenocarcinoma. All four lines have a characteristic cuboidal epithelial morphology, and their epithelial origin was confirmed by positive staining with a monoclonal antibody which reacts specifically with the keratin filaments of simple epithelia. The adenoma‐derived lines display ultrastructural features characteristic of colonic epithelium including desmosomes, microvilli and mucin droplets. One of the adenoma‐derived cell lines, designated PC/AA, has retained differentiated functions in culture, namely mucin production, after 21 in vitro passages. PC/AA has a karyotype of 46, XY with no detectable chromosome rearrangements. The adenoma‐derived lines could be passaged from clumps of cells but not from single cells even in the presence of 3T3 feeder cells. The carcinoma‐derived line, designated PC/JW, could however grow from single cells in the presence of a feeder layer. The one premalignant adenoma‐derived line tested so far, PC/AA, did not produce tumours in athymic nude mice. In contrast, the carcinoma‐derived line, PC/JW was tumorigenic in athymic nude mice. PC/JW produced moderately welldifferentiated tumours which were histologically similar to the adenocarcinoma from which the cell line was isolated. PC/JW has a near‐diploid chromosome number with an isochromosome (I q), an isochromosome (14q) and an (Xp; 17q) translocation. Unidentified marker chromosomes were present in a few cells. The features at present which distinguish the carcinoma‐derived line from the adenomaderived lines are tumorigenicity, growth from single cells and chromosomal abnormalities. The isolation and characterization of differentiating human epithelial cell lines at different stages in malignant transformation provide an opportunity to examine the cellular and molecular mechanisms controlling tumour progression in the large intestine, and to obtain an insight into the multistep process of human epithelial carcinogenesis.
Geographical distribution of lung cancer in the USSR
Authors: Wagner R. I. , Merabishvili V. M. 
Published: February 2007

AbstractDuring recent years medico‐geographical studies on lung cancer in the USSR have been intensified. The results of these studies are reflected in works on the geographical distribution of lung cancer and on the influence of unfavourable natural‐economic factors upon lung cancer incidence. The steady increase in lung cancer morbidity and mortality throughout the world is one of the urgent problems of today. Numerous studies have been carried out, and these have identified several aetiological factors which play a certain role in lung cancer development (smoking, occupational hazards, air pollution by industry and traffic). These studies have shown lung cancer to be one of the cancers most closely associated with environmental conditions. Lung cancer is considered to be a disease of the male population inhabiting highly industrialized cities and countries. However, lung cancer incidence has also been increasing recently in the female population of different countries. (V. Merabishvili, G. Tserkovny, 1981) Different levels of morbidity and mortality from lung cancer throughout the world make it necessary to undertake comprehensive studies on the complicated and everchanging relations between the health status of the population and the effect of natural and economic factors.
Characterization of african green monkey B‐cell lines releasing an adult T‐cell leukemia‐virus‐related agent
Authors: Yamamoto Naoki , Kobayashi Nobuyuki , Takeuchi Kaoru , Koyanagi Yoshio , Hatanaka Masakazu , Hinuma Yorio , Chosa Toru , Schneider Josef , Hunsmann Gerhard 
Published: February 2007

AbstractEight lymphoblastoid cell lines were established from the peripheral blood of individual African green monkeys (AGM). The AGM‐2206 line grew out spontaneously. The others ‐ AGM‐6, 7, 8, 10, 12, 13, and 16 ‐ were obtained after infection of peripheral AGM lymphocytes with cellfree culture supernatant of AGM‐2206. All lines contained, and were probably transformed by, AGM‐EBV. Moreover, they expressed immunoglobulins but lacked the Leu I T‐cell marker. Thus they were B cells. Since a high percentage of AGMs are naturally infected with a virus similar to adult T‐cell leukemia virus (ATLV), we examined these cell lines for ATLV. With immunofluorescence tests we detected ATLV‐related antigens (ATLA) in three of the eight cell lines. EBV membrane antigen was present in three out of four. The highest percentage (40%) of ATLA‐positive cells was found in the AGM‐13 line. After metabolic labelling of these cells, ATLV‐specific polypeptides p24, p19, p15, and p10 were detected. Hybridization experiments showed that both AGM‐2206 and AGM‐13 cell lines contained ATLV‐proviral DNA. Electron micrographs of AGM‐13 revealed a few type‐C particles morphologically similar to the MT‐2 virus. By cocultivation this AGM virus was able to infect and immortalize human peripheral blood lymphocytes. One such human cell line, NA‐13, expressed polypeptides closely related to ATLV core antigens but a 68,000 mol.wt. glycopolypeptide was serologically distinct from MT‐2 ATLV gp68.
Monoclonal antibody against an antigen selectively assembled into vesicular stomatitis virus virions from HeLa cells
Authors: Poláková Katarina , Závadová Zuzana , Závada Jan , Russ Gustáv 
Published: February 2007

AbstractA mouse hybridoma cell line IIB9, secreting IgG2b antibody specific for a HeLa cell antigen, was obtained by fusion of a mouse myeloma cell line with spleen cells from mice immunized with purified VSV tsO45 mutant (defective in assembly of G protein) which had been reproduced at a non‐permissive temperature in HeLa cells. The monoclonal antibody IIB9 was strictly specific for HeLa cells in two tests: (1) reaction with VSV or Chandipura virus phenotypically mixed with host cell antigen, (2) complement‐dependent cytotoxicity test (51Cr‐release).
Tumor‐cell‐platelet aggregation does not correlate with metastatic potential of rat 13762NF mammary adenocarcinoma tumor cell clones
Authors: Estrada Jaime , Nicolson Garth L. 
Published: February 2007

AbstractThe ability of tumor cells to induce platelet aggregation has been correlated with their capacities to colonize the lungs of experimental animals. We tested this hypothesis by studying the ability of cloned, low‐passage metastatic tumor cell lines derived from rat 13762NF mammary adenocarcinoma to aggregate rat platelets in vitro and in vivo, and we then compared this activity to metastatic potential by determining the incidence of lung metastasis after subcutaneous or intravenous inoculation of the tumor cell clones into syngeneic rats. Our results failed to show a correlation between in vitro platelet‐aggregating activity and metastatic potential. In this system we could not detect platelet‐aggregation activity with the most metastatic tumor clone, while the least metastatic clone clearly possessed high platelet‐aggregating activity. In addition, by measuring changes in blood platelet and fibrinogen concentrations at various intervals following intravenous injection of tumor cell clones, we were able to confirm in vivo the observed in vitro differences in their plateletaggregating activities. Thus, platelet aggregating activity is heterogeneously expressed among 13762NF cell clones and appears unrelated to spontaneous or experimental metastasis in this tumor system.