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R B Owens

Publications and source records attributed to R B Owens.

18 recordsLinked to original sources
PubMed2001

Syndecan-1 (CD138) immunoreactivity in bone marrow biopsies of multiple myeloma: shed syndecan-1 accumulates in fibrotic regions.

Syndecan-1 (CD138) mediates myeloma cell adhesion, and loss of syndecan-1 from the cell surface may contribute to myeloma proliferation and dissemination. Flow cytometry analysis of myeloma cells in bone marrow specimens shows heterogeneity in cell surface syndecan-1 expression. It is not known whether weaker expression correlates with more aggressive disease. However, recent reports suggest that variations in syndecan-1 staining intensity on myeloma cells may be an artifact of specimen handling. In this study, we evaluate syndecan-1 expression in bone marrow biopsy sections from 28 multiple myeloma patients, to elucidate the heterogeneity of syndecan-1 expression in situ. Immunoreactivity for syndecan-1, using the antibody B-B4 (CD138), was found in more than 95% of multiple myeloma cells in 27 of 28 biopsies. However, one biopsy had more than 50% CD138-negative cells and cells with weak CD138 expression were identified in the majority of cases. Loss of syndecan-1 did not appear to relate to myeloma cell differentiation. In addition, syndecan-1 was detected on intravascular and intrasinusoidal myeloma cells suggesting that loss of syndecan-1 may not be required for extramedullary dissemination. Bone marrow biopsies from nine additional patients, with variable CD138 staining intensity on myeloma cells as determined by flow cytometry, were studied by immunohistochemistry. The heterogeneous CD138 expression was confirmed in situ, with weakly positive cells concentrated in areas of reticulin fibrosis. These cells had a disrupted pattern of membrane staining in contrast to the strong linear membrane staining seen in the other multiple myeloma cells. In addition, the fibrotic stroma stained intensely for syndecan-1. Accumulation of syndecan-1 within the extracellular matrix of the marrow likely is derived by shedding of the molecule from the surface of myeloma cells. Because syndecan-1 can act to regulate the activity of heparan-binding growth factors, these reservoirs of syndecan-1 may play a critical role in promoting myeloma pathogenesis, or in regeneration of the tumor after chemotherapy.

Biopsy↗
PubMed1996

Secondary pericardial malignancies: a critical appraisal of the role of cytology, pericardial biopsy, and DNA ploidy analysis.

The authors studied 112 pericardial fluids (45 malignant, and 67 benign) from 63 men and 33 women. All cytologic (n = 112) and histologic (n = 61) specimens were reviewed. Statistical analysis was conducted in 61 paired cytology and histology specimens (45 malignant and 16 benign) and correlated with available ploidy analysis of fluid specimens (n = 34). In cases of malignancy (41 patients), the primary site was known in 34 patients, whereas no origin for metastatic disease was apparent in 3 patients. Pericardial cytology yielded the initial diagnosis in four patients. After careful review of all cytology and histology specimens, seven truly discrepant cases were noted, six of which had positive cytology. Tissue biopsy sampling error was the cause for such discrepancies. DNA diploidy obtained by flow cytometry correlated with benign cytology, whereas aneuploidy was associated with malignant cytology in a total of 32 of 34 cases (94%). Cytologically malignant effusions rendered diploid DNA in 2 of 10 cases (20%). In conclusion, cytology is the single most important parameter in the evaluation of secondary pericardial malignancy and should be considered the gold standard. Causes for false-negative cytologic diagnoses include scant cellularity and obscuring blood. Hence, careful screening is recommended. The low sensitivity of flow cytometric DNA analysis does not favor its routine use.

Adolescent↗
PubMed1992

Deoxyribonucleic acid (DNA) ploidy and proliferative characteristics of metastatic squamous cell carcinoma determined by flow cytometric analysis.

BACKGROUND: The deoxyribonucleic acid (DNA) index and the proliferative index (the fraction of cells in the S phase) can be independent prognostic indicators of the biologic aggressiveness of certain malignant neoplasms. OBJECTIVE: To determine whether the DNA index or proliferative index could predict metastases in cutaneous squamous cell carcinoma. METHODS: Nineteen different metastases from 15 patients with primary cutaneous squamous cell carcinoma (SCC) were reviewed, graded, and had DNA proliferative indexing performed by fluorescent activated cytometry. A control group of 13 patients with primary cutaneous SCC without metastases were studied in a similar manner. RESULTS: No significant difference between the metastatic and the nonmetastatic SCC groups for either DNA index or proliferative index (non-paired t-test) was observed. No correlative association with histologic grading with DNA index or proliferative index was observed for either group. CONCLUSION: We conclude that aneuploidy and S-phase fraction by fluorescent activated cytometry are not significant predictors of potential metastases in cutaneous squamous cell carcinoma.

Carcinoma, Squamous Cell↗
PubMed1984

Relationship between karyotype of tissue culture lines and tumorigenicity in nude mice.

There are many factors, other than the absence of an immune response, that are responsible for the successful transplantation of xenografts to nude mice. We have defined, in this study, the relationship between karyotype and transplantability of xenografts into nude mice, using a library of 85 tumor and normal tissue culture lines. Each of these lines had been previously passaged in tissue culture for more than 10 generations. 53 of these 85 lines were classified as diploid, whereas 32 lines were classified as heteroploid. These tissue culture lines were transplanted to groups of 4-10 unmanipulated and antilymphocyte serum (ALS)-treated nude mice and serially monitored for 12 weeks. Only 19% of the diploid lines were successfully transplanted into unmanipulated nude mice, and only 30% were successfully transplanted into ALS-treated nude mice. In comparison, 50% of the heteroploid lines were successfully grafted into unmanipulated nude mice, and a total of 60% were successfully transplanted into ALS-treated nude ice. 12 of the 53 diploid lines can be classified as being pseudodiploid on the basis of rearranged chromosomes or other minor karyotype anomalies. 8 of these 12 pseudodiploid lines were successfully transplanted into nude mice, further strengthening the relationship between abnormal karyotype and transplantability. Tumor karyotype is an additional parameter which should be added to the variables involved in the successful transplantation of tumors to nude mice.

Animals↗
PubMed1980

Tumorigenicity of human malignant lymphoblasts: comparative study with unmanipulated nude mice, antilymphocyte serum-treated nude mice, and X-irradiated nude mice.

The ability of unmanipulated, antilymphocyte serum (ALS)-treated, and X-irradiated nude BALB/c female mice (in their 13th backcross generation) to serve as hosts for 10 human lymphoblastoid cell lines as well as for peripheral blood lymphocytes from healthy humans was compared. The 10 lymphoma lines included 7 previously characterized and reported in the literature. Significant differences with respect to both latency period for tumor appearance and success rate for tumor transplantation were detected among the 3 experimental groups. The unmanipulated mice were poor recipients for lymphoma heterotranplants, and tumors were produced in only two instances. In contrast, 6 tumor lines were successfully transplanted in mice inoculated with ALS, and all 10 lines were successfully transplanted in X-irradiated recipients. Although tumors were readily produced in ALS-treated and X-irradiated mice, no gross or histologic evidence of focal or distant metastases was apparent. Human lymphoblastoid cells were recultured, essentially unchanged, from the heterotransplants from 6 of 7 tumors tested. Although the tumor line HT 1460, originally from a human lymphoma, was successfully transplanted in all 3 groups, only mouse cells were recultured. The use of X-irradiation, rather than ALS, to immunosuppress nude mice offers a more standardized method for heterotransplanting human tumor cell lines and permits ready comparisons between laboratories. Furthermore X-radiation permits transplantation and subsequent study of lymphoblastoid tumors that are otherwise difficult to successfully transplant in nude mice.

Animals↗
PubMed1977

Immunobiology of heterotransplanted human tumors in nude mice.

The immunobiology of heterotransplanted human tumors was investigated following transplantation into nude mice of human bronchogenic, colon, rectal, ovarian, gastric, endometrial, vaginal, bladder, renal, esophageal, embryonic cell, pancreatic, and breast carcinoma, as well as fibrosarcoma, rhabdomyosarcoma, malignant melanoma, astrocytoma, Wilm's tumor, endometrial hyperplasia, and hydatidiform mole. Several of these tumors were passaged up to 15 generations. During these passages no changes in latency period for tumor development or in histology were noted. There were significant differences between several tumors in the minimum number of cells required for successful transplantation; such differences were independent of the basic biologic aggressiveness of the individual tumors. Nude mice that received transplants of fibrosarcoma and endometrial carcinoma had increased serum IgM and numbers of spleen cells and complement receptor lymphocytes. No such changes were noted for mice that received transplants of malignant melanoma, In contrast, there were no apparent differences in the responses of nude mice, who were given transplants of human tumors, to be T-cell mitogens concanavalin A or phytohemagglutinin or in the number of theta-bearing spleen cells. The success rate for transplantation was significantly improved when explants, rather than single-cell suspensions, were performed. Tumors transplanted to nude mice derived from strictly homozygous matings behaved like tumors transplanted to mice born of heterozygous mothers. Finally, despite the dramatic size of subcutaneous tumor nodules, there were no examples of invasion or distant metastases.

Animals↗
PubMed1977

Two syngeneic cell lines from human breast tissue: the aneuploid mammary epithelial (Hs578T) and the diploid myoepithelial (Hs578Bst) cell lines.

We characterized two human cell lines (Hs578T and Hs578Bst), which provide several unique features that should be useful in the study of breast disease. Hs578T, derived from a carcinosarcoma, is epithelial in origin. Hs578Bst, established from normal tissue peripheral to the tumor, is myoepithelial in origin. This is the first report of companion cell lines, one malignant and one normal, established from the same organ.

Aneuploidy↗
PubMed1976

The biology of human cells in tissue culture. I. Characterization of cells derived from osteogenic sarcomas.

We have extensively characterized cell lines derived from six human osteosarcomas. The growth properties of these cultures were compared to those of fibroblastic cultures derived from skin of osteosarcoma patients and skin of bone-marrow of normal individuals. Each tumor-derived line showed some but not all of the abnormal growth properties usually associated with malignant transformation, indicating that tumor cells rather than normal stromal cells had in fact been cultured. The parameters measured included saturation density, cell morphology, growth pattern, growth on contact inhibited monolayers of normal fibroblastic or epithelial cells and tumorigenicity in immunosuppressed mice. Although the skin fibroblasts from the osteosarcoma patients appeared normal in vitro, they showed a greater ability to grow in immunosuppressed mice than did normalfibroblasts. This observation suggests that all fibroblasts of osteosarcoma patients may have an increased propensity for malignant transformation.

Adolescent↗
PubMed1976

Source, alterations, characteristics and use of a new dog cell line (Cf2Th).

A cell line derived from normal fetal canine thymus (Cf2Th) has been in culture since 1967. During cultivation the cells have changed morphologically from a fibroblast-like to flat, fusiform appearance and karyologically from diploid (2n=78) with 76 telocentric autosomes to hypodiploid with newly formed atelocentric chromosomes. The cells retain canine characteristic enzyme activity (G6PD and LDH) as well as cell membrane fluorescence and are free of mycoplasma. High passage cells produce tumors in ATST mice. No endogenous viruses have been detected in these cells. No original publication exists, to date, on the origin of this line, but seed stocks thereof have been distributed to many laboratories and the cells have served as experimental substrates in a number of published works on oncology albeit under different designations. The present information is offered in order to establish the provenance of this valuable cell line and to list characteristics which may serve to monitor for its purity and to distinguish it from other existing cell lines of dog origin also in common use.

Animals↗
PubMed1976

Epithelial cell cultures from normal and cancerous human tissues.

Thirty epithelial cell strains were isolated from human carcinomas and normal epithelial tissues by collagenase digestion and selective removal of fibroblasts with trypsin-Versene. Most strains were obtained from metastatic carcinomas or epithelia of the urinary and intestinal tracts. The success rate for growth of both neoplastic and normal tissues (excluding skin) was 38%. Six of these strains showed gross morphologic and chromosome changes typical of malignant cells. Nine resembled normal epithelium. The other 15 exhibited some degree of morphologic change from normal.

Cell Division↗
PubMed1971

Effect of rifampicin and two of its derivatives on cells infected with Moloney sarcoma virus.

It is shown that rifampicin, and especially the related antibiotic 2',6'-dimethyl-N(4')-benzyl-N(4')- [desmethyl]rifampicin (DMB-rifampicin) can inhibit focus formation by Moloney sarcoma virus on BALB/3T3 tissue cultures. At 10 mug/ml DMB-rifampicin totally inhibits focus formation while reducing virus replication by at least a factor of fifty and cell proliferation by only a factor of three. These observations, taken together with those of others, suggest a role for an RNA-dependent DNA polymerase and the gene for its synthesis both in normal cell processes and in the transformation process.

Animals↗
PubMedDate not supplied

Reticulocyte counting by flow cytometry. A comparison with manual methods.

The reticulocyte count (RC) is a key diagnostic test in the evaluation, classification, and response to therapy of anemia. The RC, as determined by manual methods, has a frustrating inherent imprecision owing to its binomial counting statistics (i.e., low counts/low precision) and inaccuracy because of inter- and intraobserver variability as to what indeed is a reticulocyte. Fluorescent activated cytometric (FACS) analysis of reticulocytes by thiazole orange (TO) is a rapid, relatively simple, and precise method for counting reticulocytes. The automated method counts 10,000 cells or more vs. 1,000 cells counted by the manual method. Although inherently more precise, the FACS method may be inaccurate owing to the presence of Howell-Jolly bodies, nucleated red blood cells (RBCs), sickled cells, or giant platelets. The RC by FACS is well correlated with the manual method and the reference ranges are similar. A new parameter by FACS, the reticulocyte maturation index (RMI), provides an independent measurement of reticulocyte RNA content. Although the RMI does not correlate with RC either by FACS or manual methods, it does provide an independent parameter of erythropoietic activity and may be useful in predicting bone marrow engraftment or further subclassifying anemias. Determination by FACS of the RC offers significant advantages over manual methods in monitoring a patients erythropoietic response. However, one must be cognizant of potential pitfalls in the method.

Adult↗