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B A Spengler

Publications and source records attributed to B A Spengler.

At least 55 records · Page 3Linked to original sources

Characterization of human neuroblastoma cell lines established before and after therapy.

Six new cell lines have been established from human neuroblastomas. Cell line SMS-KAN, from primary tumor before therapy, and line SMS-KANR, from bone marrow after chemotherapy and radiotherapy, were established from the same patient. Cell lines SMS-KCN (from primary tumor before any therapy) and SMS-KCNR (from bone marrow after chemotherapy) were established from another patient. Two other lines (SMS-MSN and SMS-SAN) were established from different patients before any therapy was given. Cell lines established from recurrent disease after chemotherapy (SMS-KANR and SMS-KCNR) had significantly shorter doubling times and increased plating efficiencies compared to those of cell lines derived from the same patient before chemotherapy (SMS-KAN and SMS-KCN). All cell lines contained tyrosine hydroxylase, aromatic L-amino acid decarboxylase, and dopamine-beta-hydroxylase. Measurable amounts of choline acetyltransferase were also detected in SMS-KAN and SMS-KANR. Karyotype analysis showed all cell lines except SMS-MSN to be pseudodiploid with modal numbers of 46 and deletions of the short arm of chromosome 1; SMS-MSN had a modal number of 57-58 chromosomes. All cell lines had double-minute chromosomes, except SMS-KANR, which had abnormally banding regions. These new cell lines provide in vitro models of neuroblastoma suitable for the study of differences in neuroblastoma cell populations before chemotherapy as compared to the cell populations that proliferate after therapy.

Catecholamines↗

Differential drug sensitivity of human neuroblastoma cells.

A 6-day in vitro growth-inhibition assay was used to determine relative sensitivity of six human neuroblastoma cell lines to three classes of cancer chemotherapeutic agents: antimetabolites (methotrexate, methasquin, and cytarabine); antimitotics (vincristine, vinblastine, vindesine, colchicine, and demecolcine); and antibiotics (dactinomycin and doxorubicin). Human fibroblast lines served as a reference standard. Whereas response to antimetabolites by four of five neuroblastoma lines tested was similar to that of fibroblasts, SK-N-MC cells were significantly more sensitive (fivefold to 16-fold) to the three drugs. Human neuroblastoma cell lines were also differentially sensitive to antimitotics, especially to vincristine. In particular, SK-N-MC, IMR-32, and LA-N-2 cells were threefold to 17-fold more sensitive to this drug than were the SK-N-SH and SK-N-BE(2) lines. With the exception of SK-N-SH, all of the human neuroblastoma lines were considerably more sensitive to vincristine than were human fibroblasts. The same three highly vincristine-responsive lines were also significantly more sensitive to the other alkaloidal drugs as compared to fibroblasts. However, human neuroblastoma and fibroblastic cells responded similarly to the two antibiotics. The only cellular attribute consistently correlated with greater sensitivity to the antimitotics among the six cell lines tested was expression of the neurotransmitter biosynthetic enzyme choline acetyltransferase. A differential response to the vinca alkaloids was also exhibited by clonal sublines of SK-N-SH. One subpopulation (SH-EP) expressing a nonneuronal, substrate-adherent, variant phenotype was at least fourfold to eightfold more drug sensitive than its neuroblastic counterpart (SH-SY5Y) or the parental SK-N-SH population. In addition to confirming reports of clinical efficacy of the various classes of agents, these data have demonstrated a variation in response possibly related to type or degree of neuronal differentiation and emphasize the importance of understanding the phenotypic diversity commonly observed in neuroblastoma.

Antibiotics, Antineoplastic↗

Role of human chromosome 11 in determining surface antigenic phenotype of normal and malignant cells. Somatic cell genetic analysis of eight antigens, including putative human Thy-1.

The expression of eight serologically and biochemically distinct human cell surface antigens defined by monoclonal antibodies was examined on a panel of rodent-human somatic cell hybrids. Cosegregation was observed for human chromosome 11, and surface expression of all eight antigens was studied. Serological analysis of hybrids containing defined segments of human chromosome 11 permitted the regional assignment of genes controlling antigens JF23 (90 kD glycoprotein), G344 (25 kD), T43 (85 kD), A124, and NP13 to chromosome 11pter-q13, and of genes controlling Q14 (130 kD), MC139 (35 kD), and K117 (25 kD) to chromosome 11q13-qter. K117, the putative human Thy-1 antigen, was expressed at high levels in chromosome 11-containing hybrids constructed with mouse neuroblastoma cells, but showed little or no expression in hybrids constructed with mouse L cells. A similar pattern of expression in hybrids was found for MC139, an antigen shared by neuroectoderm-derived cells and normal and malignant T lymphocytes. T43 is a marker of malignant tumors (but not benign tumors) derived from a number of T43- epithelia, and the regional assignment of the T43 locus on chromosome 11 raises questions about its possible involvement in the specific rearrangements of this chromosome seen in human malignancies.

Animals↗

Cell surface antigen of human neuroblastomas is related to nuclear antigen of normal cells.

The localization of MC25, an antigen first detected on the surface of human neuroblastoma cells, was determined in cultured cells and tissues. Neuroblastoma cell lines (15/17) express the antigen on the surface and in the cytoplasm (scMC25+), whereas 156/160 cell lines derived from other normal and malignant human cell types are scMC25-. However, MC25 is found in the nucleus of scMC25- cells (nMC25+), presenting a discrete granular pattern. In scMC25+/nMC25- neuroblastoma lines, apparent antigen shifting from the cell surface/cytoplasm to the nucleus accompanies variant formation, which represents a transition in the neuronal differentiation program of these cells. Results of immunohistochemical studies with human tissues parallel the findings with cultured cells. Almost all cell types are scMC25-/nMC25+; basal cells of the epidermis are the only cells constitutively expressing cMC25; and a population of neurons are the only scMC25-/nMC25- cells. Alternative localization of MC25 to different cellular compartments and antigen shifting are reminiscent of the behavior of certain developmentally regulated antigens in Drosophila and Xenopus.

Antibodies, Monoclonal↗

Gene amplification-associated cytogenetic aberrations and protein changes in vincristine-resistant Chinese hamster, mouse, and human cells.

We carried out cytogenetic studies of four Chinese hamster, mouse, and human cell lines selected for high levels of resistance (500- to 4,000-fold) to vincristine (VCR) by a multistep selection procedure. All cells examined contained gene amplification-associated metaphase chromosome abnormalities, either homogeneously staining regions (HSRs), abnormally banding regions (ABRs), or double-minute chromosomes (DMs); control actinomycin D- and daunorubicin-resistant hamster lines did not exhibit this type of chromosomal abnormality. VCR-resistant Chinese hamster sublines exhibited both increased synthesis of the protein V19 (Mr 19,000; pl = 5.7) and increased concentrations of V19 polysomal mRNA. When VCR-resistant cells were grown in drug-free medium, level of resistance, synthesis of V19, and amount of V19 mRNA declined in parallel with mean length of the HSR or mean number of DMs per cell. Cross-resistance studies indicate that VCR-resistant cells have increased resistance both to antimitotic agents and to a wide variety of agents unrelated to VCR in chemical structure and/or mechanism of action. Our studies of tubulin synthesis in Chinese hamster cells indicate no overproduction of tubulin or presence of a mutant tubulin species. Comparison with antifolate-resistant Chinese hamster cells known to contain amplified dihydrofolate reductase genes localized to HSRs or ABRs strongly suggests that the HSRs, ABRs, or DMs of the Vinca alkaloid-resistant sublines likewise represent cytological manifestations of specifically amplified genes, possibly encoding V19, involved in development of resistance to VCR.

Animals↗

Three human cell surface antigen systems determined by genes on chromosome 12.

The mouse monoclonal antibodies AbA123, AbA127, AbK152, AbM68, and AbV1 were derived after immunization with cultured human tumor cells or melanocytes. Antibodies AbA123, AbA127, and AbK152 recognize human cell surface antigens expressed on most cultured human cells and show an identical pattern when tested on a panel of 47 human cell lines. They recognize at least two different epitopes on the same glycoprotein complex, designated A123/A127, which consists of 30,000-and 40,000-mol-wt glycopeptides. Antigens M68 and V1 are also expressed on most cultured human cell types but show distinct patterns of distribution on the cell line panel. The antigens defined by AbM68 and AbV1 have the characteristics of glycolipids. They are heat stable, and immunoprecipitation of metabolically labeled cell lysates did not yield any detectable components when analyzed by SDS-polyacrylamide gel electrophoresis. Serological typing of a panel of 23 independently derived mouse-human and Chinese hamster-human somatic cell hybrids showed unequivocally that the expression of cell surface antigens A123/A127, M68, and V1 segregates with human chromosome 12. The analysis of hybrids containing karyotypically defined deletions of chromosome 12 permitted the assignment of the loci determining the expression of antigens. A123/A127 and V1 to region 12cen-qter, and the locus determining the expression of antigen M68 to region 12cen-pter. These antigens can be distinguished from the cell surface molecules previously assigned to chromosome 12 and thus represent new assignments to this chromosome.

Adenocarcinoma↗

Two cell-surface markers for human chromosome 1 in interspecies hybrids.

Monoclonal antibodies AbAJ9 and AbT87 define two distinct human cell-surface antigen systems (1, 2). Both antibodies react with a wide variety of cultured human cell types but not with rodent cell lines. AbAJ9 identifies a glycoprotein of 140,000 mol wt and AbT87 identifies a glycoprotein of 60,000 mol wt. The genetic control of antigen expression was studied in rodent-human somatic cell hybrids containing different subsets of the entire human chromosome complement, using an immune rosetting assay for serological analysis and hybrid selection. The presence of human chromosome 1 was found to be both necessary and sufficient for expression of antigens AJ9 and T87 in hybrid cells. Two independent gene loci on chromosome 1, designated MSK -1 for AJ9 and MSK -2 for T87 , control the expression of these antigens. We have assigned MSK -1 to region 1 cen-p22 and MSK -2 to region 1q32 -qter, using hybrids containing only fragments of human chromosome 1.

Animals↗

Somatic cell genetic analysis of human cell surface antigens: chromosomal assignments and regulation of expression in rodent-human hybrid cells.

The expression of 13 newly defined human cell surface antigens identified by monoclonal antibodies was studied in a panel of reduced rodent-human somatic cell hybrid clones. For each antigenic system the segregation of antibody reactivity was concordant with the segregation of a specific human chromosome, permitting the chromosomal assignment of 13 gene loci determining antigen expression. The antigens can be placed in four groups on the basis of their patterns of control in the hybrid cells. (i) Presence of a single human chromosome is necessary and sufficient for antigen expression; L230 (assigned to chromosome 2), AJ425, K15 (chromosome 3), SR84 (chromosome 5), JF23, Q14 (chromosome 11), SV13 (chromosome 15), and F10 (chromosome 19). (ii) AJ2 (chromosome 10) and J143 (chromosome 17); two antigens coded for by separate human chromosomes but associated as a molecular complex on the surface of AJ2+/J143+ human cells. (iii) F8 (chromosome 19); antigen expression dependent on the growth characteristics of hybrid cells: substrate-adherent cells are F8+, whereas cells growing in suspension are F8-. (iv) AO122 and F23 (chromosome 15); antigen expression controlled by the permissive/inducing vs. nonpermissive/noninducing nature of the rodent fusion partner. Hybrids derived from both antigen-positive and antigen-negative human cells can express AO122 and F23 but only when specific rodent cell types are used for hybridization: N4TG-1 neuroblastoma and L cells, but not RAG renal carcinoma cells, permit AO122 expression, whereas RAG and L cells, but not N4TG-1 cells, permit F23 expression. The rapidly expanding list of monoclonal antibodies defining human cell surface molecules provides a range of markers to probe the genetic regulation of antigen diversity in somatic cells.

Animals↗

Specific DNA sequence amplification in human neuroblastoma cells.

Southern blot analysis of a number of EcoRI-digested human neuroblastoma DNAs has revealed the presence of a family of discrete restriction fragments, the majority of which are amplified in most, but not all, of the neuroblastoma cell lines tested. None of these sequences is abundantly present in DNA from other human tumors of different tissue origins, including several either known or presumed to contain amplified DNA. Hence, these sequences appear to be specifically amplified by neuroblastoma cells. Hybridization with metaphase chromosomes in situ has localized these sequences to either the homogeneously staining regions or double-minute chromosomes of different neuroblastoma cell lines, indicating that these chromosomal structures, although present in cell lines established from different patients, share many sequences and may have a common, but as yet unknown, function.

Base Sequence↗

Coordinate morphological and biochemical interconversion of human neuroblastoma cells.

This study was undertaken to determine whether the two type of cells (one neuroblast-like and the other epithelial in appearance) of the human neuroblastoma line SK-N-SH in culture undergo morphological interconversion, whether conversion is bidirectional, and whether there are coordinate neurochemical changes. Phenotypic analysis of serially isolated neuroblast clones (SH-SY, SH-SY5, SH-SY5Y) revealed conversion to epithelial-like cells. Conversely, conversion also was promoted from an epithelial-like clone (SH-EP) to neuroblastic subclones. Cell origin could be verified because of a marker chromosome specific to SH-EP. Only neuroblastic subclones of SH-EP contained activities for tyrosine hydroxylase and dopamine-beta-hydroxylase, enzymes unique to catecholamine neurons; epithelial-like cells lacked activities for these enzymes. These findings indicate a coordinate morphological and biochemical interconversion of neuroblastoma SK-N-SH cells and reveal a plasticity in phenotypic expression in malignant neuronal cells.

Cell Line↗

Drug resistance in Chinese hamster lung and mouse tumor cells.

Studies of Chinese hamster and mouse cells with high levels of acquired resistance to dactinomycin, daunorubicin, or vincristine have shown that these different permeability mutants all display similar phenotypic alterations: dramatic changes toward normal cell morphology and growth behavior and substantially reduced oncogenic potential. All three resistant cell types show increased expression of a high molecular weight plasma membrane glycoprotein species, gp150. Uniquely, vincristine-resistant cells contain gene amplification-associated chromosome abnormalities (homogeneously staining regions or double minute chromosomes), and they oversynthesize a low molecular weight cytosolic protein (V19). Cells grown in the absence of drug are phenotypically unstable. Revertant cells decline in resistance, length or number of homogeneously staining regions or double minute chromosomes, and expression of gp150 and V19. These proteins are thus candidate products of amplified genes which may or may not be manifested cytogenetically. The phenomena of drug resistance and reverse transformation are currently being addressed in protein phosphorylation studies.

Animals↗

Neurotransmitter-synthesizing enzymes in 14 human neuroblastoma cell lines.

Fourteen human neuroblastoma cell lines were studied for expression and regulation of neurotransmitter-synthesizing enzymes. All cell lines contained activities of adrenergic and/or cholinergic neurons and 13 expressed activities for both. None contained enzymes for serotonergic or GABAergic neurons. Enzyme activity was characteristic for a given cell line. Enzyme activity in cell lines was sensitive to growth phase, culture medium, and concentration of fetal bovine serum.

Aromatic-L-Amino-Acid Decarboxylases↗

The fine structure of continuous human neuroblastoma lines SK-N-SH, SK-N-BE(2), and SK-N-MC.

Cell cultures of the continuous human neuroblastoma lines SK-N-SH, SK-N-BS(2), and SK-N-MC at exponential and stationary growth phase have been examined by electron microscopy. At the level of fine structure these cells did not show typical neuronal differentiation such as extensive granular endoplasmic reticulum or neurites with microtubules and neurofilaments. Instead they were characterized by abundant free ribosomes, moderate Golgi complexes, and usually scant granular endoplasmic reticulum, features similar to the fine structure of early normal embryonic autonomic neurons. However, in several respects appearance of differentiated features of the neuroblastoma cells did not follow the pattern observed for normal neurons, suggesting noncoordinate expression of neuronal phenotypic properties. First, an occasional neuroblastoma cell had as extensive granular endoplasmic reticulum as would be found at later stages in normal developing neurons. Second, the cellular processes of these neuroblastoma cells did not have the fine structure of developing or mature axons in vivo. Third, few dense core vesicles were found in SK-N-SH and SK-N-BE(2), though these organelles are numerous in early normal adrenergic neurons and the adrenergic character of these two lines is apparent from other studies that have demonstrated expression of neurotransmitter synthesizing enzymes (SK-N-MC is cholinergic). The fine structural characterization of these continuous human neuroblastoma cell lines will allow this parameter to be utilized with other approaches in future experimental studies.

Cell Line↗

Metaphase chromosome anomaly: association with drug resistance and cell-specific products.

Large, homogeneously staining chromosome regions which lack the longitudinal differentiation ordinarily revealed by cytogenetic "banding" methods have been found in antifolate-resistant Chinese hamster cells and also in human neuroblastoma cells established in vitro. The drug-resistant cells are characterized by excessive production of the target enzyme, dihydrofolate reducatase, while the human neuroblastoma cells have phenotypes of normal neuronal cells. The homogeneously staining region appears to represent a novel metaphase chromosome anaomaly which may have functional significance in cells with specialized properties.

Aspartic Acid↗

A novel chromosome abnormality in human neuroblastoma and antifolate-resistant Chinese hamster cell lives in culture.

Four cell lines, SK-N-SH, SK-N-MC, SK-N-BE(2), and IMR-32, established in vitro from tumor tissue of patients with neuroblastoma were analyzed by trypsin-Giemsa banding methods. In two of the lines a large, abnormally staining chromosome region was observed. This "homogeneously staining region" (HSR) was considerably longer than any of the bands present in normal human cells and, as revealed by both G- and Q-banding, stained with an intermediate intensity. It was located on chromosomes No 6, 10, 17, or 19 of the SK-N-BE(2) cell line and on chromosome No 1 of the IMR-32 line. In concurrent studies, long HSR's were also observed in Chinese hamster sublines that had been exposed to and had developed high levels of resistance to methotrexate or methasquin and high levels of activity of target enzyme dihydrofolate reductase. For several sublines with the highest levels of enzyme activity, approximately 2% of the total cell protein was dihydrofolate reductase. Of 13 independently derived sublines with acquired resistance to antifolate, only those 7 with greater than 100-fold increases in enzyme activity consistently exhibited HSR's. These regions comprised 2-5% of the total length of the chromosome complement and were specifically localized, as demonstrated by G-banding. Analysis of chromosome replication patterns of the HSR in human neuroblastoma and in drug-resistant Chinese hamster cells by tritiated thymidine radioautography indicated that the long, abnormally staining region replicated relatively rapidly and synchronously and terminated replication before the midpoint of the S phase. The HSR thus appeared to represent a novel chromosome abnormality that may be present in cells with specialized functions. Drug-resistant Chinese hamster cells were characterized by overproduction of target enzyme, whereas human neuroblastoma cells had phenotypes of normal neuronal cells. Whether the HSR is transcriptionally active was not elucidated.

Animals↗