Relationship between flow cytometric parameters, steroid receptors, and menopausal status in breast cancers.

Of 163 human breast cancers examined, 68% contained detectable aneuploid populations, whilst 32% had apparently normal DNA distributions. A slightly higher incidence of aneuploidy was observed in pre-menopausal patients (83%) than in post-menopausal patients (66%). Also, pre-menopausal patients had slightly higher proportions of S-phase or cycling (S + G2 + M) cells. Estradiol receptor negative (ER-) tumours from post-menopausal patients were found to have the lowest incidence of aneuploidy (59%) and ER- tumours from pre-menopausal patients the highest (91%). There were no significant differences in the proportions of cycling nuclei when receptor status and menopausal status were considered. A weak relationship is shown to exist between flow cytometric data and two common prognostic indicators of breast cancer, namely receptor status and menopausal status.

Effects of dihydrotestosterone, 17 beta-estradiol and dexamethasone on mitogen--and allogeneic--induced lymphoblastogenesis.

In contrast to the in vivo action of sex steroids the steroidal hormones dihydrotestosterone (DHT) and estradiol (E2) produced a marked variable response on mitogen-induced lymphoblastogenesis. DHT and E2 at concentrations of 10(-11) mol l-1 incubated with mononuclear cell fraction in the presence of mitogens PHA, Con A and PWM caused inhibition, stimulation or no effect. Separation of T and B cell fractions and incubation with DHT and E2 likewise produced variations in response. However, dexamethasone (DEX) strongly inhibited proliferation of all cell fractions, particularly at the higher steroid concentrations. These results suggest that the reported effects of in vivo administered sex hormones on the immune system might possibly be mediated by a precursor cell of peripheral blood mononuclear cells, and that the in vitro system may not be a reproducible test for determining an individual's immunoendocrine status.

Nickel sulphide-induced rhabdomyosarcomata in rats.

Fifty-nine Fischer rat tumors and eleven Hooded rat tumors induced by intramuscular injection of Ni3S2 were examined and their histopathologic and cytologic characteristics studied. Nine out of eleven Hooded rat tumors metastasized whereas 15 out of 59 Fischer rat tumors metastasized within 30 days. Histopathological characterization of the Ni3S2-induced tumors was made according to their preponderant cellular constitution. They were grouped into six types: well-differentiated rhabdomyosarcomas, poorly-differentiated rhabdomyosarcomas, embryonal rhabdomyosarcomas, mesenchymal tumors, leiomyosarcoma-like tumors and fibrosarcoma-like tumors. Forty-seven of total of 70 were rhabdomyosarcomas. Tumors with shorter latent periods in Fischer rats and tumors with fleshy and soft texture demonstrated a higher incidence of metastases.

Neuraminidase effect on the growth of a transplantable nickel sulfide-induced rat tumor.

Exposure of a weakly immunogenic nickel sulfide-induced Fischer rat tumor to Vibrio cholerae neuraminidase inhibited tumor growth in normal recipients. These recipients were found to be more resistent to a subsequent tumor inoculation.

Growth and cytogenetic characteristics of nickel sulphide-induced rhabdomyosarcomas in rats.

Rhabdomyosarcomas induced by single intramuscular injections of nickel sulphide (Ni3S2) in Fischer and Hooded rats were cultured in vivo and in vitro to study their growth characteristics and chromosomal constitution. The tumor cell suspensions cultured in vitro exhibited more myogenic differentiation on the coverslips than those cells grown in vivo in diffusion chambers. A characteristic feature of in vivo cultures was the appearance of microclusters which resembled the primary tumors. Chromosome analyses of primary tumors revealed that a majority of these had a modal number in the diploid or near diploid range. Fischer rat primary tumor cells exhibited abnormal configurations including rings, dicentrics and triradials. A comparison of the chromosome make-up of the primary tumors and their metastases was performed on four sets of tumors. Three out of four metastases examined showed the diploid chromosome make-up characteristic of the primary tumors suggesting that the tumors with the diploid or near diploid chromosome constitution are more likely to produce metastases.

Preparation of cells from suspensions for correlative scanning electron and interference microscopy.

Neutrophils from bovine milk and blood platelets from dog plasma were washed in PBS, fixed in GA, dehydrated, suspended in a drop on a formvar-coated slide and immediately critical-point-dried in CO2. After coating with Pt-Pd the specimens were examined in an SEM. The same cells were then examined by interferometry (Int) in a light microscope, and the dry mass was determined. It is shown that this preparation method for both types of microscopes (SEM and Int) appears to give adequate results as far as fine surface structure (SEM-appearance) and dry mass determinations (Int) are concerned. The method has the advantage of a more precise characterization of individual particles, than would have been possible, if both methods of microscopy (SEM and Int) had been employed on the same sample, but on different specimens.