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Biomedical subjects

J F Lechner

Publications and source records attributed to J F Lechner.

84 records · Page 5Linked to original sources
PubMed1980

Chromosomal analysis of human prostatic adenocarcinoma cell lines.

Although detailed cytogenetic analysis has been carried out in many types of cancer, there is little information on the chromosomal makeup of prostatic cancer cells. Karyological analyses of cell lines derived from both metastatic and primary prostatic carcinoma have been carried out by Q-, C-, and sequential banding techniques. The metastatic line, PC-3, isolated from a bone marrow specimen, is an established epithelial line which is tumorigenic in nude, athymic mice and forms colonies in semisolid agar suspension. A subline, PC-3/M, was isolated from a PC-3-induced mouse tumor. Karyotypic analysis of PC-3 by Q- and C-banding showed the cells to be aneuploid at all culture passage levels. The modal chromosome number shifted from 62 to 55 between the 5th and 50th passages. PC-3 has a unique karyotype. Chromosomes 2, 3, 5, 15, and Y were always absent. At least 11 different marker chromosomes were observed. The subline, PC-3/M, had a similar karyotype and retained the parental PC-3 markers. PC-3/M had a more restricted chromosomal frequency distribution range. Nearly 73% of the PC-3/M cells examined had 60 or 61 chromosomes in contrast to the wide distribution seen in PC-3. Silver staining for nucleolus organizer regions indicated that the number of functional nucleolus organizer regions in PC-3 was proportional to the number of acrocentric chromosomes. Banding analysis of PC-5-PI isolated from primary prostatic adenocarcinoma indicated that this line also had a characteristic karyotype with 28% pseudodiploid and 72% pseudotetraploid components. All metaphases examined were partially trisomic in chromosome 9 and lacked a demonstrable Y chromosome.

Adenocarcinoma↗
PubMed1979

Application of the principles of enzyme kinetics to clonal growth rate assays: an approach for delineating interactions among growth promoting agents.

The interaction of mitogenic factors on a single cell type and the comparative activity of a given factor in diverse cell types have been studied by applying the principles of Michaelis-Menten kinetics to clonal growth data. Such comparisons are facilitated by derivation of two parameters; Km mitogen, the mitogen concentration that gives half-maximal clonal growth and a theoretical maximal growth rate, RMAX T. Both parameters are analogous to the Km and VMAX as applied to enzymatic reactions. Use of these parameters permits meaningful comparisons between cells with different growth rates. Using kinetic analysis of dose-response data, we found that normal human epithelial cells require 200 times more fetal bovine serum protein (FBSP) than a malignant line to multiply at their respective half-maximal rates. Further, the Km FBSP of normal cells was reduced to that of the malignant line by the inclusion of growth factors (EGF or FGF, and hydrocortisone) in the medium. On the other hand, even though greater levels of serum were required when growth factors and hydrocortisone were not present, their inclusion did not alter RMAX T. Interactions between mitogenic factors were shown to be unidirectional. Although EGF reduced the Km FBSP, FBSP did not change the Km EGF. The same type of analysis revealed that hydrocortisone, which potentiated the mitogenic activity of EGF did not change the Km EGF. Kinetic analysis of cell growth should prove useful in studies on the relation between growth and tumor promotion as well as in the evaluation of growth-inhibiting chemotherapeutic agents.

Blood Proteins↗
PubMed1979

Establishment and characterization of a human prostatic carcinoma cell line (PC-3).

The establishment, characterization, and tumorigenicity of a new epithelial cell line (PC-3) from a human prostatic adenocarcinoma metastatic to bone is reported. The cultured cells show anchorage-independent growth in both monolayers and in soft agar suspension and produce subcutaneous tumors in nude mice. Culture of the transplanted tumor yielded a human cell line with characteristics identical to those used initially to produce the tumor. PC-3 has a greatly reduced dependence upon serum for growth when compared to normal prostatic epithelial cells and does not respond to androgens, glucocorticoids, or epidermal or fibroblast gowth factors. Karyotypic analysis by quinacrine banding revealed the cells to be completely aneuploid with a modal chromosome number in the hypotriploid range. At least 10 distinctive marker chromosomes were identified. The overall karyotype as well as the marker chromosomes are distinct from those of the HeLa cell. Electron microscopic studies revealed many features common to neoplastic cells of epithelial origin including numerous microvilli, junctional complexes, abnormal nuclei and nucleoli, abnormal mitochondria, annulate lamellae, and lipoidal bodies. Overall, the functional and morphologic characteristics of PC-3 are those of a poorly-differentiated adenocarcinoma. These cells should be useful in investigating the biochemical changes in advanced prostatic cancer cells and in assessing their response to chemotherapeutic agents.

Adenocarcinoma↗
PubMed1978

Replicative epithelial cell cultures from normal human prostate gland.

Epithelial cell cultures of the normal human prostate gland were established. The subculturing of these cultures was accomplished with a novel nonenzymatic technique. These cultures were defined as normal epithelial cells on the basis of ultrastructure, karyotype, and inability to grow in soft agar.

Cell Adhesion↗
PubMed1978

Ion selective electrode for determination of chloride ion in biological materials, food products, soils and waste water.

The chloride ion selective electrode is used for a rapid, simple, and reliable determination of chloride ion in biological materials (blood serum, urine, fish, and plant tissues), food products (milk, beef extract, nutrient broth and orange, tomato, and grapefruit juices), soils, and waste water (industrial and municipal). The method consists of treating the samples with perchloric acid (pH 1) and potassium peroxydisulfate and determining the chloride content either by a calibration curve or by known addition or analyte addition, using the chloride ion selective electrode. Such sample treatment eliminates most of the interferences occurring in the samples, including iodide, complexing and reducing compounds, and macromolecular and surface-active species. The method is suitable for a wide range of chloride concentration, e.g., 5010 ppm Cl- in nutrient broth and 4890 ppm in beef extract and as low as 12 and 80 ppm in soil extracts.

Animals↗
PubMedDate not supplied

Concurrent fluorescence in situ hybridization and immunocytochemistry for the detection of chromosome aberrations in exfoliated bronchial epithelial cells.

OBJECTIVE: A procedure was developed to allow concurrent detection of chromosome aberrations and identification of bronchial epithelial cells. STUDY DESIGN: Fluorescence in situ hybridization for chromosome 7 and immunocytochemistry for cytokeratin were performed on exfoliated bronchial epithelial cells in a sputum sample from a cancer patient. RESULTS: The Spectrum Orange-labeled alpha satellite probe for chromosome 7 produced red fluorescence, nuclei were counterstained with 4,6-diamidino-2-phenylindole (blue), and cytokeratin was visualized using a fluorescein isothiocyanate (FITC)-conjugated secondary antibody (green). CONCLUSION: This procedure allowed the rapid identification of airway epithelial cells with numerical chromosome aberrations in this sample. Ultimately, this procedure could increase the sensitivity and specificity of sputum cytology as a laboratory diagnostic tool for the early detection of lung cancer.

Antibodies, Monoclonal↗
PubMedDate not supplied

Carcinogenic responses of transgenic heterozygous p53 knockout mice to inhaled 239PuO2 or metallic beryllium.

The transgenic heterozygous p53+/- knockout mouse has been a model for assessing the tumorigenicity of selected carcinogens administered by noninhalation routes of exposure. The sensitivity of the model for predicting cancer by inhaled chemicals has not been examined. This study addresses this issue by acutely exposing p53+/- mice of both sexes by nose-only inhalation to either air (controls), or to 1 of 2 levels of 239PuO2 (500 or 100 Bq 239Pu) or beryllium (Be) metal (60 or 15 micrograms). Additional wild-type p53+/+ mice were exposed by inhalation to either 500 Bq of 239PuO2 or 60 micrograms of Be metal. These carcinogens were selected because they operate by differing mechanisms and because of their use in other pulmonary carcinogenesis studies in our laboratory. Four or 5 of the 15 mice per sex from each group were sacrificed 6 mo after exposure, and only 2 pulmonary neoplasms were observed. The remainder of the mice were held for life-span observation and euthanasia as they became moribund. Survival of the p53+/- knockout mice was reduced compared to the p53+/+ wild-type mice. No lung neoplasms were observed in p53+/- mice exposed to air alone. Eleven of the p53+/- mice inhaling 239PuO2 developed pulmonary neoplasms. Seven p53+/+ mice exposed to 239PuO2 also developed pulmonary neoplasms, but the latency period for pulmonary neoplasia was significantly shorter in the p53+/ mice. Four pulmonary neoplasms were observed in p53+/- mice exposed to the higher dose of Be, whereas none were observed in the wild-type mice or in the heterozygous mice exposed to the lower dose of Be. Thus, both p53+/- and p53+/+ mice were susceptible to 239Pu-induced carcinogenesis, whereas the p53+/- but not the p53+/+ mice were susceptible to Be-induced carcinogenesis. However, only 2 pulmonary neoplasms (1 in each of the 239PuO2 exposure groups) were observed in the 59 p53+/ mice that were sacrificed or euthanatized within 9 mo after exposure, indicating that the p53+/- knockout mouse might not be appropriate for a 6-mo model of carcinogenesis for these inhaled carcinogens.

Adenocarcinoma↗
PubMedDate not supplied

Individuals at high risk for lung cancer have airway epithelial cells with chromosome aberrations frequently found in lung tumor cells.

Identification of individuals at greatest risk of developing lung cancer could enhance the efficacy of intervention modalities, thereby greatly reducing mortality from this disease. One strategy for identifying these people is to establish molecular markers which reflect the severity of their cancerization field. Thus, investigations were initiated to determine of cells with chromosome aberrations frequently exhibited by lung tumor cells, i.e., trisomy 7, trisomy 20, and deletion of 9p23, are prevalent within the uninvolved airways of cancer patients. As a result, cells containing these aberrations were consistently found at significantly elevated levels by using fluorescence in situ hybridization (FISH). In contrast, cells collected from non-smokers who had never smoked were normal by this assay. The next objective was to determine of cells exhibiting these alterations are also present in upper airways of exposed, but cancer-free smokers and ex-uranium miners. The results showed that, although only a subset of these people will develop lung cancer in their lifetimes, they universally harbor increased numbers of abnormal cells within their airway epithelium. However, the number of sites with multiple verities of abnormal cells tended to be fewer compared with the cancer patients. Thus, quantifying cells with molecular alterations within the cancerization field of a smoker may delineate those with a lesser grade of damage, and these individuals may be at a lesser risk of developing disease. However, differences in the extent of genetic damage afforded by these assays may not clearly define individuals with pending disease, and additional molecular assays must be devised.

Bronchi↗