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Query: UMLS:C0027651 (tumor)
 685,946 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Nuclear fluorescence metachromasia of heated fixed cells subsequently stained with acridine orange was compared in smears and isolated nuclei of various types of primary tumors and normal cells from the tissues that gave rise to the tumors. The ratios of fluorescence emission at 590 and 530 nm reflect the thermal stability of chromatin in situ. The results show that the mean thermal stability of the chromatin in neoplastic cells was lower than the stability of their normal counterparts in all cases. This was found in both spontaneous and chemically induced tumors as divergent in type as a dog vaginal tumor and murine lymphocytic leukemia. These data, together with our previous observations in other neoplastic systems, indicate that reduced chromatin thermal stability may be a general characteristic of cells that have undergone neoplastic transformation and is not confined to rapidly growing tumors. The present investigation identifies the sources of variability encountered in measuring fluorescence metachromasia in slide preparations, and methods of minimizing this variability for potential cytodiagnostic application are discussed.
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PMID:Microfluorometric comparisons of heat-induced nuclear acridine orange metachromasia between normal cells and neoplastic cells from primary tumors of diverse origin. 4 93

After staining with acridine orange (AO), the nuclei of unfixed cells from the human female genital tract exhibited the same fluorescence behavior previously observed for human and murine leukocytes and mouse ascites tumor cells. With staining conditions chosen to assure saturation of the green-fluorescing AO-nucleic acid complex in normal cells, corrected fluorescence emission spectra were recorded from the entire nucleus of 341 cells taken from 32 normal and 28 abnormal patients. Intensity of the recorded spectra was expressed in phosphor particle units, a fixed arbitrary unit of fluorescence intensity, to display intensity differences among the spectra from the various cell types. In all abnormal samples, one or more cells were found with 530-nm nuclear fluorescence intensity considerably greater than the maximum intensity recorded from normal cells. Determination of the adequacy of 530-nm nuclear fluorescence intensity as a criterion for cancer detection requires additional investigation. Additional criteria, if needed, may be supplied by the metachromasy of AO-stained unfixed cells.
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PMID:Quantitative fluorescence spectrophotometry of acridine orange-stained unfixed cells. Potential for automated detection of human uterine cancer. 5 89

Cytogenetic observations were made on 6 cell lines (MOB-1, MOB-2, MOB-3, MSB-1, HPRS Line 1, HPRS Line2) originating from Marek's disease lymphomas and 2 clones (1104-B, 1104-X-5) of a cell line established from an avian lymphoid leukosis tumor. The modal chromosome number was within the diploid range in all the lines except HPRS Line 1 and HPRS Line 2, both of which had a mode at about 60. Karyotypes were grossly abnormal in 4 cell lines: trisomy for No. 1 in MOB-2; the heteromorphic No. 1 pair in MSB-1, and marker chromosomes derived from rearrangements involving No. 3 or No. 5 and unidentified elements in HPRS Lines 1 and 2. The MOB-1 line which had been characterized by cells with an apparently normal karyotype was completely taken over by cells with a heteromorphic No. 1 pair morphologically similar to the one found in MSB-1 by the 95th day of continuous growth in vitro. BUdR-acridine orange differential staining technique revealed, however, different banding patterns in these abnormal chromosomes.
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PMID:Chromosomal characteristics of six cultured lymphoblastoid cell lines originating from Marek's disease lymphomas. 6 31

Electron microscopy processing and staining of nuclei were used to localize reaction products of acridine orange staining in actinic keratosis of human skin. Electron-dense granules about 10-100 nm in diameter were seen exclusively in the euchromatin portion of the nucleus. Almost all tumor cells had granules (mean = 65; SD = 26). These granules were also occasionally observed in the dermal connective tissue cells in the lesion. However, the mean number of 10 granules seen in these cells was definitely less than that of tumor cells. Normal skin controls did not have granules except occasionally in the basal cells of the epidermis.
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PMID:Acridine orange-DNA complex in actinic keratosis. 7 May 37

Five human bladder cell lines, four derived from tumor tissue and the fifth originating from presumed benign transitional epithelium, were examined by flow cytofluorometry to estimate the DNA and RNA content per cell during exponential and stationary phases of growth. A new staining technique was employed using acridine orange to differentially stain DNA and RNA in unfixed cells made permeable to the dye and other reagents by treatment with detergent at low ph. Stemline chromosome numbers for each cell line correlated well with relative DNA content of the G1 population as measured by this technique. In addition, the simultaneous measurements of DNA and RNA per cell yielded cell cycle distributions for each cell line. The ratio of stainable RNA/DNA was lower for all cell lines derived from bladder tumors as compared to the presumed normal cell line, indicating high nuclear/cytoplasmic ratios for the former.
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PMID:Nucleic acid content and cell cycle distribution of five human bladder cell lines analysed by flow cytofluorometry. 7 Dec 71

The major purpose of the examination of the cells in the cerebrospinal fluid (CSF) is the diagnosis of malignant growths. However, unequivocal tumor cell diagnosis is often problematical, since cells of local origin can also demonstrate considerable proliferative activity and great morphological variety. In these circumstances, it is advisable to evaluate cells from several points of view. One can demonstrate morphological characteristics with panoptic staining and can gain an impression of the RNA content of a cell with acridine orange (AO) fluorescent stain. Quantitative measurements of DNA synthesis in vitro can be made by labelling with tritiated thymidine. Multidimensional cytodiagnosis gives a comprehensive impression of the quality of the cells in question and provides the clinician with information which can be valuable for subsequent diagnostic and therapeutic efforts.
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PMID:Combined application of cytodiagnostic technics to the cerebrospinal fluid. 7 88

Specimens of cells derived from tumors of the human female genital tract plus normal cells as standards have been divided into aliquots and stained according to acridine orange or pararosanilin:Feulgen procedures. Acridine orange-stained cells were slit-scanned for 535 nm nuclear fluorescence; Feulgen-stained cells were comb-scanned for 580 nm nuclear absorbance. For each specimen examined, the tumor cell:normal cell ratio of mean nuclear fluorescence following acridine orange staining was greater than the tumor cell:normal cell ratio of mean nuclear absorbance following Feulgen staining. The tumor cell:normal cell ratio of mean nuclear fluorescence ranged from 2.3 for a nonkeratinizing squamous cell carcinoma to 3.9 for a keratinizing squamous cell carcinoma. The tumor cell:normal cell ratio of mean nuclear absorbance ranged from 1.4 for a mixed mesodermal sarcoma to 2.3 for a small cell squamous cell carcinoma. These results indicate that the elevated nuclear fluorescence intensity from acridine orange-stained tumor cells cannot be explained solely on the basis of elevated Feulgen:DNA content. An alternative hypothesis, consistent with these results, is that DNA is the principal binding substrate for intranuclear acridine orange and that the DNA of certain tumor cells is more accessible to acridine orange than is the DNA of normal cells.
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PMID:A comparison of acridine orange and Feulgen cytochemistry of human tumor cell nuclei. 7 21

Ether-permeabilized (nucleotide-permeable) Escherichia coli cells respond to alkylating and arylalkylating carcinogens with DNA excision repair, as assessed by their stimulation of DNA repair synthesis. In the present work, we have investigated whether DNA repair synthesis in ether-treated E. coli cells can serve as a general indicator to monitor the DNA-binding of carcinogens, mutagens and antitumor agents. Therefore, a standard assay was developed and comparative analyses were performed on 11 ultimate carcinogens, 10 proximate carcinogens, 2 tumor promoters, 6 mutagens, and 12 antitumor agents. All ultimate carcinogens (alkylating, acylating, arylalkylating agents) and mutagens (e.g., hydrogeen peroxide, acridine derivatives) caused DNA excision repair in wild type cells as measured by [3H] dTMP incorporation and simultaneously inhibited replicative DNA synthesis to various extents. Control experiments with the mutant cells uvrA and uvrB were performed to determine whether the pyrimidine-dimer-specific UV-endonuclease was involved in the removal of DNA damage. This was found to be true for the ultimate carcinogens (Ac)2 ONFln, mitomycin C, and for very reactive alkylating carcinogens. None of the ultimate carcinogens induced repair polymerization in mutant cells lacking the 5'-3' exonucleolytic activity of DNA polymerase I. Proximate carcinogens, such as Me2NNO, 4-nitroquinoline-1-oxide and aflatoxins, did not induce excision repair in the standard assay, probably because of the inability of E. coli to perform the activation steps necessary for covalent DNA-binding. However, Me2NNO, when pretreated with Udenfriend's hydroxylating mixture, gave rise to a low level of repair polymerization in ether-treated cells. Intercalating mutagens, such as quinacrine and ethidum bromide, inhibited replicative DNA synthesis. However, they were not found to be repair-inducers. THE TUMOR PROMOters TPA and phorbol-12,13-didecanoate did not cause excision repair, even when applied at high concentrations, nor did they inhibit repair synthesis stimulated by MeNOUr or (Ac)2 ONFln. The antitumor agents may be classified into two groups on the basis of the influence they exert on DNA synthesis: members of the first group (involving BCNU and bleomycin) stimulate repair polymerization and, in addition, inhibit DNA replication. These compounds are known to bind covalently to DNA. The second group of drugs (including adriamycin and cis-Pt(II)diammine complexes) inhibits DNA replication without stimulating repair synthesis. The predominant DNA-interaction of these compounds is known to be a non-covalent (i.e., intercalative, electrostatic) binding. Our experiments show that the ether-permeabilized E. coli cell can be successfully used to test ultimate carcinogens, mutagens and antitumor agents for repair-inducing and replication-inhibiting activity. The standard test might be extended to pre- and proximate carcinogens, provided these can be suitably activated.
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PMID:The nucleotide-permeable Escherichia coli cell, a sensitive DNA repair indicator for carcinogens, mutagens, and antitumor agents binding covalently to DNA. 15 98

The work was undertaken to estimate quantitatively the functional activity of tumor cell genome and possible variations in the relationship between nuclear genome and mitochondrial genetic determinants in tumor cell. For this purpose in mice C3HA tumors of hepatocellular origin were induced with N-nitroso-N-diethylamine, tissues of one of which were subjected to successive isologous transplantation during the period over 3 years. Normal hepatic tissues were taken for the control. As a result of a series of independent experiments (actinomycin D spectrophotometric titration, acridine orange binding, template activity, nuclear RNA/DNA hybridization) the results were obtained indicating a decrease in the amount of active loci in tumor hepatocytes genome. Hybridization data also indicate that in the tumor the derepression of chromosomal genes responsible for the genetic control over mitochondria and a non-regulated de-repression of mitochondrial genetic determinants take place.
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PMID:[Several properties of the nucleic acide of nuclei and mitochondria from hepatoma induced by N-nitroso-N-diethylamine]. 17 8

During eight successive isologous passages of hepatoma induced in male C3HA mice by N-nitrosodiethylamine, no common features of tumor progression were observed, although both the mitotic pattern and ploidy differed from generation to generation. These additional cytologic criteria allowed the biochemical examination of material least changed due to tumor progression. Tumor nDNA's were characterized by greater actinomycin D (AD)- and acridine orange (AO)-binding abilities than were normal nDNA's; this could have resulted from a higher proportion of double-stranded regions in tumor DNA. Isolated tumor deoxyribonucleoprotein had both lower template activity in an RNA polymerase system and fewer AD- and AO-binding sites, when compared with the activity and sites from normal mouse liver. RNA-DNA hybridization data with the above-mentioned findings showed that in hepatoma, part of the nuclear genome was repressed. Also, RNA "new classes" appeared and a certain proportion of nuclear genes controlling mitochondrial protein biosynthesis were derepressed in tumor mitochondria. The hybridization of mitochondrial RNA (mtRNA) and DNA revealed new classes of pulse-labeled RNA's in in vitro-incubated liver mitochondria that were absent from intact cell organelles; the hybridization properties of in vivo- and in vitro-formed hepatoma mtRNA's were similar. Competition and hybridization experiments demonstrated that in tumor mitochondria in vivo, some new classes of RNA existed. Hepatoma mitochondrial mRNA had a higher metabolic stability than did normal mRNA.
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PMID:Nucleic acids from subcellular fractions of N-nitrosodiethylamine-induced hepatoma in mice. 18 62


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