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Biomedical subjects

F Traganos

Publications and source records attributed to F Traganos.

At least 145 records · Page 8Linked to original sources
PubMed1981

Effects of aclacinomycin on cell survival and cell cycle progression of cultured mammalian cells.

The effects of aclacinomycin (ACM; NSC 208734) on cell viability, growth, and colony formation were investigated in suspension (Friend leukemia and L1210) and adherent (Chinese hamster ovary) cell systems. Cell cycle progression and the effect of the drug on various transition points in the cell cycle (i.e. G1 to S phase, through a window in early S phase and G2 phase to mitosis) were monitored by flow cytometry. Formation of Chinese hamster ovary cell colonies was inhibited by 50% following 24 hr of exposure to 0.05 micrograms ACM per ml whereas 1 hr of exposure to 1.0 micrograms ACM per ml reduced colony formation by only 30%. Stationary cultures required a drug concentration more than 5 times higher to reduce colony formation by an equivalent amount when present for 24 hr. Short-term (1-hr) exposure to drug concentrations up to 1.0 micrograms/ml had no effect on colony formation of stationary-phase Chinese hamster ovary cells. Cell growth was inhibited by 50% in suspension cultures of Friend leukemia and L1210 cells when exposed for 24 hr to 0.024 and 0.053 micrograms ACM per ml, respectively. Continuous drug exposure of Friend leukemia and L1210 cells to ACM concentrations of 0.05 to 0.1 micrograms/ml led to a slow down in cell progression manifested as an accumulation of cells in G2 + M phase by 24-hr and then in G1 phase by 48-hr culture. However, brief (1-hr) exposure of L1210 cells to 0.5 micrograms/ml resulted in an irreversible accumulation of cells in G2 + M phase. A more detailed examination of drug effects on the cell cycle determined that 0.1 micrograms ACM per ml resulted in a slow down in L1210 cells leaving G1 phase and entering mitosis and an accumulation of cells in G2 phase, although early S-phase cells appeared unaffected. At a 5 times higher drug concentration, exit of cells from G1 was almost completely halted, passage of cells through early S was slowed, and the entrance of cells into mitosis plateaued 3.5 hr after addition of the drug; G2-phase cells were only mildly affected. The RNA content of all cells examined was reduced by 35 to 50% depending upon dose and time of exposure. These findings are discussed in terms of the known biochemical effects of ACM on RNA and protein synthesis.

Aclarubicin↗
PubMed1981

Effects of the L isomer (+)-1,2-bis(3,5-dioxopiperazine-1-yl)propane on cell survival and cell cycle progression of cultured mammalian cells.

The effects of the L isomer (+)-1,2-bis(3,5-dioxopiperazine-1-yl)propane (ICRF 159; NSC 169780) on cell viability, growth, and progression through the cell cycle were investigated in suspension cultures of murine leukemia (Friend leukemia and L1210) cells and normal human lymphocytes stimulated with phytohemagglutinin and in adherent cultures derived from human neuroblastoma and Chinese hamster ovary (CHO) cells. CHO cell colony formation was inhibited by 50% following either an 8.5-hr exposure of exponentially growing cells to 10 micrograms ICRF 159 per ml or a 24-hr exposure to 3 micrograms ICRF 159 per ml. This effect was cell cycle phase specific; early G1- and G2-phase cells were more sensitive than were late-G1- or early and mid-S-phase CHO cells. Stationary-phase CHO cells were unaffected by the drug at concentrations up to 500 micrograms/ml. Incubation of L1210 cells with 3 micrograms ICRF 159 per ml for 24 hr or with 10 micrograms ICRF 159 per ml for 6 hr inhibited cell growth by 50%. In contrast, 24-hr incubation of human lymphocytes with up to 50 micrograms ICRF 159 per ml had no effect on their viability or on their ability to be stimulated by phytohemagglutinin. Constant exposure of Friend leukemia, L1210, human neuroblastoma, and phytohemagglutinin-stimulated human lymphocytes to 10.0 to 50 micrograms ICRF 159 per ml resulted in inhibition of cell division which led to cell growth at higher ploidy levels. Thus, proliferating human cells of normal or tumor origin and murine leukemic cell lines all had a similar sensitivity to the drug. Detailed analysis of cell cycle progression in L1210 cells in the presence of the drug determined that cell progression through G1 phase (G1A to G1B transition) was slowed by approximately 50%. The rate of traverse of cells through S phase was also slowed. However, the most pronounced effect was the accumulation of cells in G2 phase occurring almost immediately after addition of the drug. The data suggest that the L isomer has a range of cytotoxicity and identical cytokinetic effects similar to that of the clinically tested racemate (+/-)-ICRF 159 (NSC 129943) and, therefore, that the more soluble L isomer may have increased clinical applicability.

Animals↗
PubMed1981

Flow cytometric analysis of bone marrow in a patient with resistant neuroblastoma.

Using flow cytometric analysis, we followed changes in a patient's bone marrow which was infiltrated with cells resistant to chemotherapy. Samples taken prior to, during, and after treatment with dianhydrogalactitol (2 days), cytosine arabinoside and hydroxyurea (2 days), and Adriamycin (2 days) contained an aneuploid population of cells which exhibited changes in ploidy, viability, and distribution in cell cycle compartment. The restricted changes in cell ploidy and viability of tumor cells encountered as well as limited increases in S phase on day 4 and G2 phase on day 6 with a rebound on day 9 of G1 phase cells suggest the tumor to be sensitive to dianhydrogalactitol but not to the other agents used.

Antineoplastic Agents↗
PubMed1980

Failure of accumulation of cellular RNA in hamster cells stimulated to synthesize DNA by infection with adenovirus 2.

AF8 cells are temperature-sensitive mutants of the cell cycle derived from baby hamster kidney (BHK) cells which arrest in the G1 phase when incubated at the nonpermissive temperature. RNA accumulation was studied in these cells by flow cytofluorimetry following serum stimulation or adenovirus 2 infection. Serum stimulation caused an increase in the amount of RNA per cell, which reached a maximum in S and G2 cells, as repeatedly reported in the literature. However, adenovirus 2 infection caused a fraction of cells to enter S phase without any concomitant increase in the amount of RNA per cell.

Adenoviruses, Human↗
PubMed1980

Bladder cancer diagnosis by flow cytometry. Correlation between cell samples from biopsy and bladder irrigation fluid.

Results of flow cytometry (FCM) examinations of bladder irrigation specimens were compared with those of FCM examinations of cell suspensions from bladder biopsies of 44 urologic patients. The fluorescent dye, acridine orange (AO), was used to stain DNA and RNA differentially and abnormal urothelial cells were identified by their relative content of nucleic acids. Granulocytes and squamous cells could be distinguished from transitional cells in this procedure, and did not interfere with the analyses. Of 28 patients with papillary carcinoma, carcinoma in situ, and invasive carcinoma 27 were identified through FCM examination of irrigation cytology specimens; the one false-negative result was from a low-grade papillary carcinoma. Of 7 patients with papilloma, FCM examinations of irrigation specimens were positive in 4 and negative in 3. Results of FCM studies of biopsy specimens were in good but not complete agreement with those of irrigation specimens. In several cases, irrigation FCM disclosed tumor stemlines that were not identified in biopsy specimens. Discrepancies of this kind seemed most likely due to differences in sampling. Irrigation FCM seems to be a sensitive method for assessing multiple-site bladder tumors, and may be a useful technique for monitoring the course of conservatively managed bladder tumors.

Acridine Orange↗
PubMed1980

Flow cytometry in bladder cancer detection and evaluation using acridine orange metachromatic nucleic acid staining of irrigation cytology specimens.

A new technique for simultaneous multiparameter deoxyribonucleic acid, ribonucleic acid and nuclear size measurements by flow cytometry was applied to the examination of bladder irrigation cytology specimens from 107 urologic patients. The cell samples from patients with bladder carcinoma could be distinguished from normal by 2 features: 1) an increase in the proportion of bladder epithelial cells with more than diploid deoxyribonucleic acid and 2) aneuploid cell peaks. These criteria identified 12 of 13 cases of invasive carcinoma, 24 of 28 cases of carcinoma in situ and 11 of 13 cases of papillary carcinoma. An increased proportion of cells with more than diploid deoxyribonucleic acid or aneuploidy was found in 9 of 14 patients with papilloma and 6 of 19 patients with a history of bladder tumors but no evident disease at present--these were believed owing to increased epithelial proliferative rates or nuclear chromatin abnormalities not visible by light microscopy. None of the 20 patients who had never had bladder tumors was abnormal. While the results in this small clinical trial have been most encouraging an additional descriptor of nuclear chromatin structure is believed necessary to discriminate benign, reactive proliferative epithelium from neoplasm when the latter is near diploid or shedding few cells. Studies to develop such a parameter presently are under way.

Acridine Orange↗
PubMed1980

Effects of ellipticine on cell survival and cell cycle progression in cultured mammalian cells.

The effects of ellipticine [5,11-dimethyl-6H-pyrido(4,3-b)carbazole; NSC 71795] on cell viability, growth, and colony formation were investigated in suspension (Friend leukemia and L1210) and adherent [Chinese hamster ovary (CHO)]tumor cell systems as well as in mitogen-stimulated human peripheral blood lymphocyte cultures. Cell cycle progression and the terminal point of action of the drug were monitored by flow cytometry. Ellipticine was cytostatic for all cell lines tested, blocking cells in G2 phase following 24 hr constant exposure at concentrations in the range of 1.0 microgram/ml. A 10 times higher drug concentration was required to block cells in G2 if the cells were exposed for only 30 min to the drug followed by 23.5 hr culture in drug-free medium. Formation of CHO cell colonies was inhibited by 50% following exposure to ellipticine for 2 hr at 6.0 microgram/ml or for 24 hr at 0.3 microgram/ml. Fifty % cell kill in asynchronously growing Friend leukemia and L1210 cells was obtained following exposure to ellipticine for 24 hr at 2.0 microgram/ml and 1.15 microgram/ml, respectively, whereas human peripheral blood lymphocytes required 66 hr exposure to 1.0 microgram/ml to kill 50% of the cells. Phytohemagglutinin-stimulated lymphocytes were remarkably resistant to the cytotoxic effect of ellipticine but did display a dose-dependent inhibition of stimulation and accumulation in G2 whether the drug was added prior to our during active cell proliferation. Ellipticine, at cytostatic concentrations, had a marked effect on cellular RNA content. Friend leukemia cells, blocked in G2 by the drug, doubled their RNA content compared to control cells. L1210 and CHO cells, but not lymphocytes, also increased in RNA content following ellipticine treatment. Drug concentrations which blocked cells in G2 also led in the case of Friend leukemia and L1210 but not CHO cells to an increase in the proportion of cells with greater than 4C amounts of DNA.

Alkaloids↗
PubMed1980

Increase in cellular RNA in cells infected with DNA oncogenic viruses.

The amount of RNA per cell has been measured by flow microfluorometry in cultured cells stimulated by serum or infected with DNA oncogenic viruses (SV40, polyoma virus, and adenovirus). While all four agents stimulate, although to a different extent, cellular DNA synthesis in quiescent cells, the accumulation of cellular RNA varies. Serum, SV40, and polyoma virus cause a marked increase in total cellular RNA that is already apparent in G1 cells before entry into S. On the other hand, adenovirus 2, while capable of stimulating cellular DNA synthesis, fails to detectably increase the amount of RNA per cell. These results suggest that adenovirus 2 may act on quiescent cells through mechanisms different from those of serum, SV40, or polyoma virus.

Acridines↗
PubMed1980

Action of dihydroxyanthraquinone on cell cycle progression and survival of a variety of cultured mammalian cells.

Dihydroxyanthraquinone, 1,4-dihydroxy-5,8-bis(( (2-[(2-hydroxyethyl)amino]ethyl)amino))-9,10-anthracenedione (NSC 279836), was observed to alter the cell cycle kinetics of a variety of mammalian cell lines as monitored by flow cytometry. Continuous exposure of Friend leukemia, L1210, and Chinese hamster cells to the drug in vitro at concentrations of 1.0 to 10 ng/ml resulted in the accumulation of cells in G2 by 24 hr in culture. When cells were exposed to dihydroxyanthraquinone for 30 min, washed free of drug, and cultured in fresh medium for 24 hr, a 10 times higher drug concentration was required to produce a G2 block identical to that observed during continuous exposure. Stimulation of human lymphocytes by phytohemagglutinin could be inhibited in a dose-dependent manner by brief pretreatment of cells with the drug. However, while previously stimulated but as yet noncycling lymphocytes were profoundly affected by much lower concentrations, proliferating lymphocytes were refractory to treatment with the drug up to a concentration of 1 microgram/ml. Exposure to the drug for 24 hr, at concentrations as low as 3.2 ng/ml, inhibited colony formation of exponentially growing Chinese hamster cells by 50%, whereas stationary culture required an 8-fold higher concentration to produce the same results. Drug concentrations in the range of 0.3 to 0.8 micrograms/ml over a period of 24 hr reduced the viability of Friend leukemia and L1210 cells by 50% as measured by trypan blue dye exclusion. In contrast, human lymphocyte viability was only mildly affected following 24 hr incubation with up to 5.0 micrograms dihydroxyanthraquinone per ml. There was a marked effect on cellular RNA content in two of the cell lines tested. Friend leukemia and L1210 cells blocked in G2 by the drug manifested a 140 and 70% increase in RNA content, respectively, when compared to control cells. In addition, though suboptimal concentrations of the drug resulted in a transient accumulation of cells in G2, optimal drug concentrations not only blocked cells in G2 but in the case of Friend leukemia and L1210 cells led to an increase in the proportion of cells with greater than 4C amounts of DNA. The results obtained with dihydroxyanthraquinone were compared to those obtained previously with a nonhydroxylated analog, anthracenedione (NCS 287513).

Animals↗
PubMed1980

Effects of 9,10-anthracenedione, 1,4-bis[[2-[(2-hydroxyethyl)amino]-ethyl]amino]-, diacetate on cell morphology and nucleic acids of friend leukemia cells.

Treatment of Friend leukemia cells for 18 hours with 9,10-anthracenedione, 1,4-bis[[(2-hydroxyethyl)amino]ethyl]amino]-, diacetate (ANT) at concentrations up to 1.0 microgram/ml induced significant changes in cell metabolism and structure. Alterations in cell nucleic acid content were detected in cells stained with acridine orange under conditions such that DNA and RNA contents could be measured simultaneously by flow cytometry. Cells treated for 18 hours with ANT at concentrations of 0.05-0.1 microgram/ml became partially blocked at the G2 phase. In addition, about 30% of the cells became polyploid and demonstrated diplochromosomes at the 8C level of mitosis. The nuclear chromatin of blocked cells had an altered structure as reflected by a change in sensitivity of DNA in situ to denaturation induced by low pH. All viable cells treated with ANT for 18 hours at concentrations of 0.4-1.0 microgram/ml were blocked in G2 phase. These cells had significantly more RNA than did untreated cells. Transmission electron microscopic observations of thin-sectioned cells suggested that this increased RNA content in ANT-treated cells was mostly due to an approximately 50% increased cell diameter and partly due to a disproportionate increase in nucleolar size. In addition, electron microscopy revealed that ANT caused increased chromatin condensation and granulation. The drug had no apparent effect on production of the endogenous Friend murine leukemia virus.

Animals↗
PubMed1980

Effects of prospidine on survival and growth of mammalian cells in culture.

The effects of prospidine, chemically known as 3, 12-diaza-6,9 diazoniadispiro[5.2.5.2]hexadecane,3,12-bis(3-chloro-2-hydroxypropyl)-dichloride (NSC-166100), on cell viability, growth, and colony formation were investigated in several mammalian cell lines. Cell cycle progression and the terminal point of action of the drug were monitored by flow cytometry. Prospidine was cytostatic for two suspension cultures (Friend leukemia and L1210 cells) at a concentration of 10 mg/ml during the first cell cycle after exposure to the drug. Cells were blocked in G2 at lower concentrations of prospidine (e.g., 1.0 mg/ml) but only after 12--24 hours of continuous exposure, i.e., during the second cell cycle in the presence of drug. Cells could be observed to accumulate in G2 by 24 hours even if prospidine (0.1 mg/ml) was removed after 12 hours. A short incubation with a liver cytosol fraction (30 min) or with cultured cells (12 hr) failed to enhance the potency of the drug. Formation of colonies of the adherent Chinese hamster ovary cell line was inhibited by 50% following 24-hour exposure to 1.1 mg prospidine/ml. Under culture conditions in which cells were blocked in G2, their RNA content increased only slightly, but the incorporation of [5-(3)H]uridine into RNA was suppressed by 15--20%. Incubation of cells with prospidine increased the stability of DNA in situ to acid-induced denaturation, which thus suggested that the drug may interact with cellular DNA.

Animals↗
PubMed1980

Ellipticine-induced changes in cell growth and nuclear morphology.

Twenty-four-hour exposure of Friend leukemia (FL) and L1210 cells to 1.0 micrograms ellipticine/ml resulted in a slowdown in cell proliferation, accumulation of cells in G2 phase, an increase in cellular RNA content, and an increase in the proportion of cells with greater than 4C (tetraploid) content of DNA in both cell lines. Removal of the drug and subsequent cell culturing in fresh medium for 24 hours led to a further increase in the proportion of cells having more than a 4C content of DNA, with no change in cell number, in FL cell cultures. Distinct micronucleation and an increase in cell size without any sign of cell division were seen in FL cells so treated. In contrast, L1210 cells after transfer to fresh medium reentered the normal cell cycle, continued to proliferate, and demonstrated only a slight increase in cells with greater than a 4C content of DNA within 24 hours of removal of the drug.

Alkaloids↗
PubMed1979

Cell-cycle distribution of urothelial tumour cells as measured by flow cytometry.

The fraction of cells in S + G2 + mitosis from 54 urothelial tumours was calculated by flow cytometry after acridine orange (AO) staining of cells obtained by bladder irrigation or biopsy. Fluorescence signals emitted by the AO-stained DNA and RNA of each cell were separated optically and measured for 5,000 cells per specimen. The patients were classified by the histology of their tumours and clinical data into 5 diagnostic categories: NED (no evidence of disease, but history of bladder tumour), 3; papilloma, 8; non-invasive papillary carcinoma, 8; carcinoma in situ, 17 and invasive carcinoma, 18. The fraction of cells with DNA values in S + G2 + M of the cell cycle varied between 7 and 57% of the total, with a wide range within each diagnostic category, but no statistically significant differences between the groups. The proportion of cells in S + G2 + M from an individual tumour was not correlated with histologic grade or clinical behaviour. The possibility that some tumour cells with DNA values above G1 level are quiescent cells arrested at S or G2 is discussed.

Cell Count↗
PubMed1979

Identification of polymorphonuclear leukocytes in cytologic samples for flow cytometry.

Inflammatory cells are commonly present in cytologic specimens obtained for flow cytometry, and may interfere with the analysis of epithelial cells. We have found that detergent (Triton X-100) pretreatment in the two-step acridine orange staining procedure disrupts granulocyte cell membranes to yield bare nuclei; bladder epithelial and squamous cells on the other hand are quite resistant to the detergent treatment. Being deprived of their cytoplasmic RNA, the granulocytes lose red fluorescence. Moreover, the shearing forces in the cytometer extend the multisegmented granulocyte nuclei and align them in the direction of flow. Thus, they present as elongated objects in the measuring system, giving a large DNA fluorescence pulsewidth (nuclear size). These two phenomena make it possible to identify granulocytes in the recorded data, where they are discernible from the mononucleated leukocytes and from epithelial cells. By data selection the granulocytes can be excluded, rendering epithelial cell populations more amenable to analysis. This method may make it unnecessary to remove physically leukocytes from the specimen before flow cytometry; it may also provide a way to analyze the morphology of granulocyte nuclei and to assess methods to manipulate their membrane stability. Full protection from membrane disruption is accomplished by alcohol fixation, and partial protection by 20-30% serum.

Cytological Techniques↗