Modulation by IFN-gamma of the metastatic ability of murine, human, and H-2-transfected tumor cells.

Interferon-gamma (IFN-gamma) can enhance the experimental metastatic ability of B16 melanoma. The in vitro treatment with IFN-gamma of four clones derived from the murine mammary adenocarcinoma TS/A increased the number of lung colonies observed after intravenous injection in syngeneic mice. The spontaneous metastatic ability of these clones was not altered by the IFN-gamma pretreatment nor by daily intratumor injection of low-dose IFN-gamma.

Myogenic differentiation of human rhabdomyosarcoma cells induced in vitro by antineoplastic drugs.

The effect of various antineoplastic drugs (1-beta-D-arabinofuranosylcytosine, 5-azacytidine, cisplatin, dactinomycin, epirubicin, vincristine, and the activated metabolite of cyclophosphamide, mafosfamide) on cell differentiation in vitro was investigated using a human alveolar rhabdomyosarcoma cell clone, RMZ-RC2. These cells are able to differentiate spontaneously from small mononuclear proliferating elements to terminal, extremely elongated multinuclear structures resembling myotubes; morphological differentiation is accompanied by the expression of myosins, in particular the embryonic isoform, which was used in this study as a specific marker of myogenic differentiation. The proportion of differentiated myosin-positive cells, which was around 10-15% in control cultures 10-15 days after seeding, was increased by some drug treatments up to 30-40%; the proportion of multinuclear elements was also increased.

Tumorigenic and metastatic ability of SV40-transformed BALB/c cell lines and MHC antigen expression.

Tumorigenic and metastatic potential were studied in relation to class I MHC expression in four different SV40-transformed BALB/c cell lines. All the lines studied, tumorigenic or not, expressed both H-2Kd and Dd, so MHC antigens did not seem to be involved in the control of SV40-transformed cells' growth in vivo. Lung metastases were observed in all tumour-bearing mice.

Human rhabdomyosarcoma cells in nude mice as a model for metastasis and differentiation.

We investigated the ability of alveolar (RMZ-RC2) and of embryonal (RD) human rhabdomyosarcoma cell lines to grow and metastasize in nude mice. Both cell lines produced local tumors, but failed to give rise to spontaneous metastases. When RD cells were injected intravenously into nude mice pretreated with cyclophosphamide (in order to depress primarily natural killer activity), several large lung colonies were obtained.

Different metastatic aggressiveness by murine TS/A clones: ultrastructure, extracellular glycoproteins and type IV collagenolytic activity.

Cell ultrastructure, extracellular matrix glycoproteins, and type IV collagenolytic activity have been examined in four murine TS/A clones characterized by different metastatic aggressiveness. In vitro, highly metastatic clones (E) exhibited slightly less differentiated ultrastructure, and high type IV collagenolytic activity, while low metastatic clones (F) showed a more differentiated cytotype, with either high and low collagenolytic activity. Type IV collagen, laminin, and fibronectin were expressed without correlation with the metastatic efficiency; keratin was slightly more evident in E than in F cells.

Interferon-mediated enhancement of metastasis. Are MHC antigens involved?

The relationship between major histocompatibility complex (MHC) antigens and metastasis was investigated on B16 melanoma variants. B16 cell lines express low amounts of murine MHC (H-2) antigens. A high expression can be induced in line B16-A by in vitro treatment with immune interferon (IFN-gamma) or by in vivo transplant in allogeneic mice.

Are colony-stimulating factor-producing cells facilitated in the metastatic process?

The relationship between production of Colony-Stimulating Factor (CSF) and metastasis has been investigated in the TS/A murine model. CSF production was determined in TS/A cell variants isolated through serial in vivo selection of lung metastatic nodules induced by intravenous or subcutaneous injection of tumor cells (artificial and spontaneous metastases, respectively). All the cell variants selected for high artificial metastatic ability produced higher amounts of GM-CSF in vitro and stronger haematological alterations in vivo than cells obtained by serial selection of spontaneous metastases.

Growth and metastasis in allogeneic hosts. Lack of H-2-negative or somatic hybrid variant selection.

In vitro cultured B16 melanoma cells, which were previously found to have an impaired expression of H-2Kb and Db (as evaluated by antisera absorption assay), were used to study growth and metastasis in allogeneic mice in relation to H-2 expression. The possible emergence of somatic hybrids with host cells was also examined. B16-A cells grown subcutaneously in allogeneic BALB/c mice (H-2d) did not show a lack of H-2b expression, nor the acquirement of H-2d antigens was found.

RMZ: a new cell line from a human alveolar rhabdomyosarcoma. In vitro expression of embryonic myosin.

The RMZ cell line was established from a bone marrow metastasis of a human alveolar rhabdomyosarcoma. Since the beginning of the in vitro culture, RMZ cells showed differentiation-related morphological heterogeneity: actively proliferating polygonal or spindle-shaped cells were observed along with a few multinucleated myotube-like structures and giant cells, frequently multinucleated. All these cell types were still present after over 40 passages.

Dexamethasone modulation of in vitro growth pattern and of lung colonization ability in clones of a metastatic BALB/c mammary carcinoma cell line.

The expression of steroid receptors and the in vitro responsiveness to steroids were used to investigate the cell heterogeneity of a BALB/c mammary carcinoma cell line (TS/A) by means of its high- and low-metastatic clones previously selected in vitro. All the clones studied contained appreciable levels of receptors for oestrogens and for glucocorticoids. The in vitro responses of clones to 17 beta-oestradiol were very poor and comparable; conversely, a heterogeneous pattern of responsiveness to glucocorticoids was observed.

Clones with different metastatic capacity and variant selection during metastasis: a problematic relationship.

Cells from TS/A, a metastasizing line derived from a spontaneous BALB/c mouse mammary adenocarcinoma, were injected either sc or iv in syngeneic mice, and the resulting lung metastases or lung colonies were briefly cultured in vitro and reinjected in mice by the same route; this procedure was repeated 10 times. All the variants obtained did not show a metastatic capacity higher than the parental cell line. Moreover, they gave a number of metastases significantly lower than that produced by high metastatic clones selected in vitro from TS/A.

Colony-stimulating activity from the new metastatic TS/A cell line and its high- and low-metastatic clonal derivatives.

We investigated the presence of colony-stimulating factor (CSF) in supernatants obtained from TS/A, a new metastatic murine cell line, and from its high-and low-metastatic clonal derivatives (E and F clones, respectively). TS/A cells produced a CSF in vitro that induced proliferation and differentiation of murine monocytic and granulocytic progenitors in agar cultures. In TS/A-bearing mice remarkable splenomegaly, blood granulocytosis and thymus depletion were observed along with a stimulatory activity in serum and a strong proliferative activity both in spleen and in bone marrow populations.

In vivo reexpression of H-2 antigens in B16 melanoma cells.

We have previously shown that B16-A (H-2b) murine melanoma cells, when cultured in vitro for more than ten passages, have an undetectable or reduced expression of H-2Kb and Db antigens, respectively. We have now studied the possibility to restore H-2 expression (measured by quantitative antisera absorption) in B16-A cells either by a limited (30 days) period of in vivo growth or by treatment with immune interferon. In vivo transplants in allogeneic H-2k or H-2d mice and in H-2-compatible but Mls and multiple non-H-2 loci incompatible mice restored the normal expression of Kb and Db antigens.

High-metastatic clones selected in vitro from a recent spontaneous BALB/c mammary adenocarcinoma cell line.

The metastatic TS/A line has been recently derived from a spontaneous BALB/c mammary tumor. When TS/A cells were cultured in 0.33 per cent agar, two morphologically distinct types of colonies were observed from which two sets of clones were obtained.

Impaired H-2 expression in B16 melanoma variants.

We studied the expression of H-2b alloantigens in three different B16 melanoma lines cultures in vitro. Cell lines were B16-F1 and two cell cultures (named B16-A and B16-B) newly derived from two different in vivo sublines of B16 melanoma. The assays used were in vivo tumour growth in allogeneic (BALB/c and B10.

TS/A: a new metastasizing cell line from a BALB/c spontaneous mammary adenocarcinoma.

A metastasizing mouse cell line (TS/A), originated from a mammary adenocarcinoma which arose spontaneously in a BALB/c female retired breeder, has been established in vitro. It displayed a remarkable morphologic heterogeneity, which is evident in plastic adherent cultures (cell types ranging from epithelial-like to fibroblast-like) as well as in semi-solid agar cultures. The TS/A line exhibited the presence of specific cytoplasmic estradiol receptor, with a binding activity of 16 fmoles/mg cytosol protein.

Inverse relationship between anti-SV40 TASA and anti-H-2 cytotoxic responses.

The in vitro cytotoxic response against H-2d and H-2b SV40-transformed fibroblasts was studied in a 40-h 3H-proline assay. A very low response against SV40 TASA is associated with the H-2d antigens on target cells: however, SV40-transformed H-2d cells are as immunogenic as SV40-transformed H-2b cells and prime against H-2b target cells. The data concerning in vitro amplification of the anti-SV40 TASA response and the involvement of cyclophosphamide-sensitive suppressor populations confirm the comparable immunogenicity of SV40-transformed H-2d AND H-2b cells and cannot account for the haplotype-related behavior observed with SV40-transformed target cells.

[Exposure to lead in workers in highway toll booths].

200 workers of the pay-toll stations of a Tuscan motorway were examined for PbB, FEP and urinary delta-ALA. The mean value of PbB was 37 +/- mcg/100 ml R.B.

Glucocorticoid receptor and in vitro sensitivity to steroid hormones in human lymphoproliferative diseases and myeloid leukemia.

The glucocorticoid receptor (GR) quantitation by a whole-cell assay and/or cytosol technique and the in vitro sensitivity to steroids have been assessed in peripheral blood cells from normal donors and patients with chronic lymphatic leukemia (CLL), acute lymphoblastic leukemia (ALL), lymphosarcoma cell leukemia (LSCL), acute nonlymphatic leukemia (ANLL), and chronic myeloid leukemia (CML). Within the lymphoproliferative diseases, ALL cells exhibited the highest GR concentration (regardless of the method used) and the highest in vitro inhibition of spontaneous [3H]thymidine ([3H]TdR) uptake by glucocorticoids. A significant relationship between GR concentration (whole-cell assay) and in vitro sensitivity to dexamethasone was also found.

The occurrence of multiple steroid hormone receptors in disease-free and neoplastic human ovary.

The cytoplasmic receptors for 17 beta-estradiol (ER), 5 alpha-dihydrotestosterone (AR), progesterone (PR), and cortisol (GR) have been quantified in 36 specimens from the human ovary (13 disease-free, 5 benign, and 18 malignant) by a dextran-coated charcoal (DCC) technique. The occurrence of receptor-positive biopsies were: ER 46%, AR 85%, PR 54%, GR 92%, in normal tissue; ER 40%, AR 100%, PR 20%, GR 50%, in benign tumors; and ER 67%, AR 72%, PR 50%, GR 88%, in malignant lesions. Furthermore, the simultaneous occurrence of ER and PR in malignant tumors was 50% yet all four receptors were found to be present only in 44% of the cases.