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Biomedical subjects

L Geder

Publications and source records attributed to L Geder.

At least 19 recordsLinked to original sources
PubMed1989

Effect of dimethylsulfoxide on human gliomas: correlations between the nuclear magnetic resonance spectra and the transformed phenotypes of the tumor cells.

Prolonged in vitro induction of six established human glioma cell lines with dimethylsulfoxide (DMSO) generated an adherent human fibroblastoid phenotype. The development of contact-inhibited cell growth coincided with the decreased colony-forming potential of these cells in semisolid medium and with the reduction or elimination of tumorigenicity when transplanted in athymic nude mice. These DMSO-induced changes persisted for at least 19 passages after removal of the inducer from the medium. High-resolution natural-abundance 13C nuclear magnetic resonance spectroscopy showed specific spectral differences between the cell lines with more or less malignant transformed phenotypes: the glioma cells with a higher degree of tumorigenicity and colony-forming potential exhibited more intense myoinositol signals than those with the more benign phenotype.

Animals↗
PubMed1987

Effect of differentiation inducers on growth characteristics of human glioma cell lines.

The effect of dimethylsulfoxide (DMSO) and iododeoxyuridine (IUdR) on the growth characteristics of two established human glioblastoma cell lines (FG and HMCN-1) was studied. The FG cell line has been characterized. The HMCN-1 cell line, established in our laboratory, consisted of fibroblastoid and polygonal cells that grew without contact inhibition. Subcutaneous injection of these cells into weanling athymic nude mice induced slowly growing, solid tumors that were histologically spindly with areas that were similar to the original tumor. Chromosomal analyses revealed a human heteroploid pattern with a modal number of 69. The cells of the original human glioma contained S-100 protein and glial fibrillary acidic protein (GFA protein), whereas the established cells failed to express markers. Prolonged treatment of glioma cells with DMSO generated a more adherent, normal human fibroblastoid phenotype that grew with contact inhibition. The new phenotype and proliferative restriction of these cells was evident as late as 50 days after discontinuation of treatment. The chemical induction of cell differentiation resulted in decreased tumorigenic potential in athymic nude mice.

Cell Differentiation↗
PubMed1981

Induction of persistent infection in mice and oncogenic transformation of mouse macrophages with infectious bovine rhinotracheitis virus.

Infectious bovine rhinotracheitis virus (IBRV) established long-term persistent infection in intracerebrally inoculated athymic nude mice. After intraperitoneal injection into outbred mice, virus was isolated for only 3 days from spleens and livers. In vitro inoculation of outbred mouse spleen fragments with IBRV resulted in persistent infection and subsequent transformation of spleen macrophages. The IBRV-specific membrane and intracellular antigens were detected by indirect immunofluorescence techniques in transformed cells in early in vitro passages. The presence of IBRV genetic formation was confirmed by in situ hybridization. The IBRV-transformed mouse macrophages induced fibrosarcomas and cystic tumors in athymic nude mice. Infective virus could not be rescued from transformed cells by cocultivation with rabbit kidney cells, treatment with iododeoxyuridine, or ultraviolet irradiation.

Animals↗
PubMed1980

Herpesviruses and prostate carcinogenesis.

Prostatic cancer cell cultures possessed intracellular immunofluorescent antigens specific for human cytomegalovirus (CMV) but produced no infectious virus particles. Norman human prostatic tissue yielded a CMV isolate that transformed primary human embryo lung cells in vitro. These cell transformants were highly oncogenic when transplanted to athymic nude mice. Immunological studies revealed that sera from prostatic cancer patients reacted significantly more frequently with CMV-related antigens than sera from age-, race-, and socioeconomic status-matched benign prostate hyperplasia groups. Specific reactivity against CMV-transformed cells of lymphocytes from prostatic cancer patients was also detected. These complex findings indicate that CMV may be involved in the development of prostatic neoplasia.

Animals↗
PubMed1980

Properties of mouse embryo fibroblasts transformed in vitro by infectious bovine rhinotracheitis virus.

Infection of CD-1 mouse embryo fibroblast(s) (MEF) with infectious bovine rhinotracheitis virus (IBRV) strain HMC resulted in persistent infection and subsequent transformation of these cells. IBRV-transformed MEF cultures consisted of short fibroblastoid cells, and IBRV-specific membrane and intracellular antigens were detectable in early in vitro passages by indirect imunofluorescence (IF) techniques. The presence of IBRV genetic information was confirmed in IF-positive and IF-negative cells by in situ hybridization. IBRV-transformed MEF induced fibrosarcomas in athymic nude mice given sc transplants. Infectious virus could not be rescued from the transformed cells or from tumor cells by cocultivation with rabbit kidney cells, by treatment with 5-iodo-2'-deoxyuridine, or by UV irradiation. Nontransformed control cells did not survive more than 10 in vitro passages and did not induce tumors when transplanted to athymic nude mice. These observations represent new data concerning the mouse cell-transforming potential of IBRV and confirm the presence of at least part of the virus genome in the transformants.

Animals↗
PubMed1979

Establishment and characterization of a new endometrial cancer cell line (SCRC-1).

A new human endometrial cell line, SCRC-1, has been established from a uterine adenocarcinoma. During a period of 57 weeks in culture, the SCRC-1 cells have been passaged over 100 times. Cultures have an epitheloid morphology, high mitotic activity, and a tendency to form multiple cell layers. The cells are polygonal and are arranged in pavement-like fashion. Most have multiple nucleoli, some are multinucleated, and all have heavily vacuolated cytoplasm. Pretreatment with iododeoxyuridine did not reveal viral markers by cocultivation or immunofluorescence techniques. Karyologic studies indicate that the SCRC11 cell line is essentially diploid with a small subpopulation of tetraploid cells. Over a period of 20 weeks, 1 of 14 athymic nude mice inoculated with SCRC-1 cells developed a tumor which histologically closely resembled the original human tumor. Cells were subsequently propagated from this tumor and the resulting epitheloid-like cell line was designated SCRC-1, Tu 1.

Adenocarcinoma↗
PubMed1979

Properties of human epithelioid cells established in vitro by a herpesvirus [IBRV(HMC)] isolated from cytomegalovirus-transformed human cells.

Infectious bovine rhinotracheitis virus [IBRV(HMC)], a double-enveloped herpesvirus, was isolated from human embryo lung fibroblasts transformed by cytomegalovirus (CMV). This agent was identified as an IBRV strain that was antigenically related to human CMV. Inoculation of a primary human kidney cancer cell culture with IBRV(HMC) resulted in persistent infection and subsequent establishment of a cell line [IBRV(HMC)HKC-1]. Virus-related nuclear, cytoplasmic, and cell membrane antigens were detected in these cells in early in vitro passages by anticomplement and indirect immunofluorescence tests. Infectious virus was rescued from one of the cell sublines after temperature-shock treatment at passage 26. Karyotypic analysis confirmed the human origin of the cells. Control uninfected kidney cancer cells survived only six in vitro passages. The established cells grew to more than 100 in vitro passages 1 year after initiation of the experiments and induced an epithelioid cancer of variable morphology that infiltrated nerves and muscles when inoculated sc into athymic nude mice.

Adenocarcinoma↗
PubMed1978

Immune response of prostatic cancer patients to cytomegalovirus-infected and -transformed human cells.

The indirect immunofluorescent test was used to determine the prevalence of humoral immunity to cytomegalovirus (CMV)-induced antigens in prostatic cancer patients as compared to age-matched controls. Significantly more prostatic cancer patients demonstrated high CMV-antibody titers than did the benign prostatic hyperplasia and nonurogenital cancer groups; however, no significant difference in reactivity was found between paients with prostatic cancer and transitional cell carcinoma of the urinary bladder. When screened against CMV-transformed human cell lines, the reactivity of the sera followed the rate of expression of CMV-related antigens of cell lines used in these tests.

Aged↗
PubMed1978

Infection of human amnion cells with cytomegalovirus.

Human cytomegalovirus (CMV), known to replicate in vitro in human fibroblastic cells, was found to replicate in epithelial human amnion (HA) cells. Large syncytia formed in these cells after infection with CMV; inclusion bodies were observed in the nuclei, and CMV antigens were demonstrated in both the cytoplasm and the nucleus by indirect immunofluorescence techniques. The synthesis of virus DNA was also detected, and the production of infectious virus was followed. The titers were lower (from 10(4) to 6 X 10(5) using different isolates of CMV) than those obtained in human embryo fibroblast (HEF) cells, and the replication cycle was slower in HA than in HEF cells.

Amnion↗
PubMed1978

Recognition of virally transformed cells by lymphocytes from patients with prostatic cancer.

Data presented describe the first assay using human peripheral blood lymphocytes (PBL) against two unique virally transformed cell lines in vitro. Human cells transformed by a cytomegalovirus (CMV-Mj) isolated from normal human prostate tissue were used as target cells in microcytoxicity assays with lymphocytes from 100 patients. Three target cell types were used: control human embryonic lung cells (HEL), transformed HEL cells (CMV-Mj-HEL-2), and transformed HEL cells retrieved from tumors induced in athymic nude mice (CMV-Mj-HEL-2, T-1) by injection of CMV-Mj-HEL-2 cells. PBL preparations from 84% of all patients tested significantly killed CMV-Mj-HEL-2, T-1 cells. However, only PBL from patients with prostatic carcinoma were cytotoxic for CMV-Mj-HEL-2 cells significantly more often than for control HEL. The implications of this approach are discussed.

Adult↗
PubMed1978

Replication of herpesviruses in human cells transformed by cytomegalovirus.

The replication of human cytomegalovirus (CMV) and herpes simplex virus (HSV) was studied in three human embryo cell lines (CMV-Mj-HEL-I, CMV-Mj-HEL-2, and CMV-Mj-HEL-2,T-I) transformed in vitro by human CMV. Growth studies revealed that these cells were completely resistant to infection by CMV strains ADI69 and Mj and partially resistant to HSV types I and 2. Neither virus DNA nor virus proteins were synthesized in the transformed cells infected with CMV AD169. The HSV production in CMV-transformed human embryo lung (HEL) cells was delayed when compared to the virus production in normal HEL cells and spread of HSV c.p.e. was slower in the transformed cells. The treatment of normal HEL cells with a crude extract of CMV-transformed HEL cells also resulted in inhibition of the spread of c.p.e. of HSV types I and 2. The inhibitory effect was not due to interferon since vesicular stomatitis virus replication was not affected and several experiments showed that it was not due to mycoplasma. The presence of virus inhibitor molecules in CMV-transformed cells absent in normal HEL cells is postulated.

Antiviral Agents↗
PubMed1978

Identification of a herpesvirus isolated from cytomegalovirus-transformed human cells.

Human cells transformed by cytomegalovirus and transplanted to athymic nude mice yielded a cytopathic virus, Hershey Medical Center virus, following prolonged in vitro passage of the tumor cells. The virus is a double-enveloped herpesvirus, is sensitive to ether, and is inhibited by iododeoxyuridine. No significant antigenic relationship to herpes simplex virus was detected using herpes simplex virus-immune sera in neutralization and immunofluorescence tests, but indirect immunofluorescence tests revealed cytomegalovirus-related antigenicity. Further immunological tests revealed that Hershey Medical Center virus is antigenically indistinguishable from infectious bovine rhinotracheitis virus. Thus, it appears that Hershey Medical Center virus is infectious bovine rhinotracheitis virus, which presumably appeared in the cell culture as a contaminant from fetal calf serum.

Animals↗
PubMed1978

Alterations in biological properties of different lines of cytomegalorivus-transformed human embryo lung cells following in vitro cultivation.

Diverse alterations in biological properties of CMV-transformed cell lines were observed during prolonged in vitro cultivation. In the CMV-Mj-HEL-2 parent line there was a gradual decrease in the number of cells expressing CMV-related antigens; at the same time, an increase in oncogenicity was observed. One tumour line, designated CMV-Mj-HEL-2,T-1, however, retained the original ratio of cells expressing CMV-related antigens for over 100 in vitro passages. The cells lost their original moderate oncogenicity during this period. A later increase in the ratio of cells without CMV antigenic markers was accompanied by the return of moderate tumorigenicity and karyotypic changes. Both cell lines were studied to determine sensitivity to superinfection with herpesviruses, induction of immune response in nude mice, and release of infectious virus.

Animals↗
PubMed1978

Establishment and characterization of a new human urinary bladder carcinoma cell line (PS-1).

An epithelioid cell line (PS-1) has been established from a transitional cell cancer derived from human urinary bladder. Subcutaneous injection of the epithelioid cells into weanling athymic nude mice induced solid tumors histologically similar to the original tumor. A cell line was also established from a tumor induced in the athymic nude mouse (PS-1, T-1). Both cell lines exhibited essentially identical growth characteristics and formed a monolayer growth of epithelioid cells in culture. Electron microscopic studies confirmed epithelioid morphology. No fibroblastoid elements were observed. Chromosomal analysis revealed heteroploidy with persistent marker chromosomes; all cells contained a Y chromosome. The presence of tumor-specific antigen(s) in PS-1 cells was suggested by microcytotoxicity assays with peripheral allogeneic lymphocytes from other transitional cancer cell patients. Sera of urinary bladder cancer patients reacted with nuclear antigens of the established cells.

Animals↗
PubMed1977

In vitro culture of human prostatic tissue.

A procedure is described which yields a significant percentage of long-term mixed cell cultures of human prostatic tissue. Attempts were made to suppress the proliferation of stromal fibroblasts and to characterize the cultured cells as those of prostatic origin. The problems associated with establishing epithelial cell lines are discussed.

Acid Phosphatase↗
PubMed1977

Evidence for the association of cytomegalovirus with carcinoma of the prostate.

A human genital isolate of cytomegalovirus is shown to have transformed human embryonic lung cells in vitro. These cells produce tumors when injected into athymic nude mice. Two cell lines derived from tissue from human prostatic carcinoma have survived more than 20 passages in vitro and demonstrate cytomegalovirus-specific membrane antigen. Significant humoral antibody titers against cytomegalovirus have been demonstrated. Cell-mediated lymphocytotoxicity against these transformed cells has been demonstrated in patients with urinary tract tumors. This evidence indicates that an association between cytomegalovirus and human prostatic cancer may be more than coincidental.

Adenocarcinoma↗