Growth and metastasis of Lewis lung carcinoma in the footpad of mice

When Lewis lung carcinoma cells were transplanted into the footpad of mice, exponential growth of tumour was seen from the 4th day. Intravasation of tumour cells was first seen at this time, then increased steadily up to the 10th day. Tumour cells entered the circulation by destructive degeneration of the vascular endothelium and also by transcellular passage, mainly through capillaries, venules and thin-walled tumour vascular channels. Multiple sites of entry of tumour cells into the circulation were frequently found. The rate of intravasation of tumour cells into the circulation was the same at the proximal, middle and distal portions of the tumour.     

Glucose-6-phosphate dehydrogenase and succinate dehydrogenase in metastatic cells of Lewis lung carcinoma

By the experimental model of the Lewis lung carcinoma we studied the activity of glucose-6-phosphate-dehydrogenesis (G6PDH) and succinic-dehydrogenesis (SDH) in the carcinoma itself, the lung metastases, the peripheral blood. A set of carcinoma, lung sections, peripheral blood smears were studied by histochemical techniques day by day since the 3rd day to the 15th one after the carcinoma grafting. The reported results allow us to conclude that G6PDH looks like a determinant of metastatic cell survival and growth and can be regarded as a marker of metastatic cells in the present model.     

The distribution of 14C-imipramine in mice bearing Lewis lung carcinoma

The distribution of ¹⁴C-imipramine (10 mg/kg ip) and several of its metabolites in tumor, lung, liver, and kidney was investigated in male BDF₁ mice bearing Lewis lung carcinoma. In contrast to other tissues, the tumor exhibited a pronounced absorption phase of ¹⁴C-imipramine; peak concentrations were reached approximately 2 hours after administration. The lung accumulated more imipramine than other tissues at early time points; however, by 12 hours the lung had the lowest tissue/plasma ratio of ¹⁴C-imipramine-derived radioactivity of the tissues studied. In both lung and tumor, the metabolic profile of imipramine was similar, with unchanged imipramine predominating; 2-hydroxyimipramine was the principle metabolite in liver. The presence of Lewis lung tumor had minimal effects on the distribution and metabolism of imipramine.     

Progressive atrophy of the thymus in mice carrying Lewis lung carcinoma grafts

Summary A rapid and progressive thymus atrophy in B₆D₂ mice following transplantation of Lewis lung carcinoma cells is reported. Spleen weight, however, increased in tumor-carrying animals. Tumor extracts failed to induce these alterations. The mechanism of these perturbations of the immune system in tumor-carrying animals is discussed.This work was supported by the Norwegian Cancer Society     

Protein-bound polyamines in the plasma of mice grafted with the Lewis lung carcinoma

Protein-bound polyamines were isolated from the plasma of mice using antipolyamine antibodies covalently linked to magnetic latex spheres. Their subsequent separation by polyacrylamide gel electrophoresis (PAGE) showed that in plasma from normal mice, 3 proteins (27, 55 and 82 kDa) carrying polyamines could be visualized, whereas in mice bearing the Lewis lung carcinoma at least 8 other proteins of higher molecular mass (5 of 94, 110, 130, 145 and 160 kDa, and 3 of greater than 170 kDa) had bound polyamines. These protein-bound polyamines could be detected from the first week after tumour graft; they increased during the second and third week but decreased thereafter. These proteins were not bound by immunolatex spheres preincubated with spermine bound to a protein-carrier insulin. Moreover, the appearance of these protein-bound polyamines was not a consequence of the inflammatory process since in mice infected with heat-inactivated Brucella abortus, with the exception of a 65 kDa protein, polyamines were bound to the same proteins found in normal mice. In mice grafted with the Lewis lung carcinoma the concomitant decrease in transglutaminase-mediated polyamine (e.g. putrescine) binding capacity of plasma proteins provides additional evidence for the presence in vivo of polyamines already bound to plasma proteins.     

Interferon-mediated inhibition of prostaglandin synthesis in human mononuclear leukocytes

In this study, the question of whether human leukocyte-derived and fibroblast-derived interferon had an effect on prostaglandin metabolism in human peripheral blood mononuclear cells has been considered. Both leukocyte- and fibroblast-derived interferon were potent inhibitors of mononuclear cell prostaglandin synthesis at low physiological concentrations. Inhibition required a minimum incubation of 1 hr. Interferon had no effect on release of arachidonic acid; synthesis of hydroxy fatty acids was slightly increased.     

Long-term human breast carcinoma cell lines of metastatic origin: Preliminary characterization

Summary Nineteen human breast carcinoma cell lines have been established as continous cultures during the past 6 years in our laboratory. This preliminary report is designed to list the lines by their designated code numbers (MDA-MB) and present a brief summary of their morphological, cytogenetic and biochemical characteristics. Sixteen of our lines were obtained from pleural effusions, two from brain metastases, and one from pericardial fluid. All lines have been shown to be distinct entities and are uncontaminated by HeLa cells or each other. A lq marker chromosome is present in all but one of the lines examined. This research was sponsored by the National Cancer Institute Contract NO1-CB-23869; Institutional Grant 5S 07 RR 5511-15 awarded by the Division of Research Resources, and a Kelsey-Leary Grant NO 974.     

Inhibition of the growth of Lewis lung carcinoma in syngeneic mice by Salmonella antigens.

Administration of a protein antigen preparation from Salmonella enteritidis 11RX at the site of challenge with Lewis lung carcinoma inhibited tumour development in mice previously immunised with live bacteria, but not control mice. The kinetics of tumour growth indicated that the inhibition of tumour development was due to a reduction of the initial tumour inoculum rather than the development of specific anti-tumour immunity.     

Effect of cellular glutathione depletion on cadmium-induced cytotoxicity in human lung carcinoma cells

The effect of glutathione depletion on cellular toxicity of cadmium was investigated in a subpopulation (T27) of human lung carcinoma A549 cells with coordinately high glutathione levels and Cd⁺⁺-resistance. Cellular glutathione levels were depleted by exposing the cells to diethyl maleate or buthionine sulfoximine. Depletion was dose-dependent. Exposure of the cells to 0.5 mM diethyl maleate for 4 hours or to 10 mM buthionine sulfoximine for 8 hours eliminated the threshold for Cd⁺⁺ cytotoxic effect and deccreased the LD_50S. Cells that were pretreated with 0.5 mM diethyl maleate or 10 mM buthionine sulfoximine and then exposed to these same concentrations of diethyl maleate or buthionine sulfoximine during the subsequent assay for colony forming efficiency produced no colonies, reflecting an enhanced sensitivity to these agents at low cell density. Diethyl maleate was found to be more cytotoxic than buthionine sulfoximine. Synergistic cytotoxic effects were observed in the response of diethyl maleate pretreated cells exposed to Cd⁺⁺. Thus the results demostrated that depletion of most cellular glutathione in A549-T27 cells prior to Cd⁺⁺ exposure sensitizes them to the agent's cytotoxic effects. Glutathione thus may be involved in modulating the early cellular Cd⁺⁺ cytotoxic response. Comparison of reduced glutathione levels and of Cd⁺⁺ cytotoxic responses in buthionine sulfoximine-treated A549-T27 cells with those levels in other, untreated normal and tumor-derived cells suggests that the higher level of glutathione in A549-T27 is not the sole determinant of its higher level of Cd⁺⁺ resistance.Abbreviations BSO DL-buthionine-(R,S)-sulfoximine - DEM diethyl maleate - DMSO dimethyl sulfoxide - GSH reduced glutathione - MT metallothionein     

Effect of the radioprotector adeturon on radiation injury in mice with Lewis carcinoma of the lung

A study was made of the radioprotective effect of Adeturon, a protective agent obtained in Bulgaria, on mice with Luis lung tumors exposed to fractionated radiation. The effect of the radioprotector on a radiation-induced injury to normal tissue was estimated by the number of leucocytes in the peripheral blood and its count, cellularity of bone marrow and spleen and the mass of the latter, and by the number of exogenous and endogenous CFUs. A pronounced radioprotective effect of Adeturon was implemented through maintaining or normalizing the indices under study impaired by tumor inoculation or irradiation.     

Enhancement of antitumor effect of cyclophosphamide by thaliblastine in Lewis lung carcinoma and L1210 leukemia in mice

Cyclophosphamide (CY) was tested in combination with the thalictrum alkaloid named thaliblastine (TBL) for therapeutic activity against early Lewis lung carcinoma and early L1210 leukemia in mice. TBL alone had no activity whereas therapy with CY and TBL was significantly better than with CY alone. The therapeutic potentiation resulting from the combination of CY and TBL is apparently due to the different mechanisms of action and the pharmacological behavior of the two agents.     

Induction of interleukins by mycoplasma in culture of human mononuclear leukocytes

Mycoplasma shows a variety of effects on immune system, including the activation of macrophage, the increase in T cell cytotoxicity, and the enhancement of the proliferation and maturation of B cells, etc. As it is well known that many cytokines regulate the immune system, it is interesting to examine whether or not human peripheral blood mononuclear cells (PBMC) produce interleukin (IL) in response to mycoplasmas. In the present study, human PMBC were incubated with 7 species of mycoplasmas for 48 hours, and IL-1 beta, IL-2 and IL-6 activities in the supernatants were determined by ELISA. All the species of mycoplasmas were able to induce IL-1 beta and IL-6, although IL-2 was induced only by M. pneumoniae. These results suggest that the influence of mycoplasma infection on immune system may be partly due to the interleukins induced by mycoplasmas.     

Regulation of the glucocorticoid receptor by glucocorticoids in human mononuclear leukocytes

We analyzed glucocorticoid receptor binding in peripheral blood mononuclear leukocytes from normal adult males and from females at the follicular and luteal phases. Healthy controls were analyzed before and after 17 days of treatment with two synthetic glucocorticoids: prednisone and an oxazoline derivative of prednisolone (deflazacort). We also studied for comparison 4 patients with adrenocortical insufficiency, two of them on long-term corticoid replacement, and 7 patients with Cushing's syndrome. Using a whole-cell competitive binding assay and 3H-dexamethasone as tracer, normal human mononuclear leukocytes (19 males, 6 females) were found to have 4,529 +/- 1,532 (mean +/- SD) binding sites per cell and a dissociation constant (Kd) of 9.5 +/- 2.3 nM. In Cushing's syndrome the receptor parameters were within the normal range. Cells from patients with untreated Addison's disease had low levels of sites per cell. The number of binding sites increased to normal after long-term glucocorticoid replacement. All the adrenal insufficiency cases had a normal Kd. Finally, following treatment with the synthetic glucocorticoid, deflazacort, the sites per cell were reduced but the Kd remained unchanged. Prednisone had no effects.     

Eicosanoids and metastasis: experimental aspects in Lewis lung carcinoma

Lewis lung primary carcinomas have been extracted for eicosanoids, and the findings examined in relation to lung metastases. The order of the 5 compounds measured was PGE2 greater than PGE1 greater than PGF2 alpha greater than 6-keto-PGF1 alpha greater than TXB2. On the basis of the observation that the balance of PGI2 and TXA2 is altered in metastasis (Honn et al., 1983), the effects of Nafazatrom, a PGI2 enhancing agent, and imidazole, a thromboxane synthetase inhibitor, were tested. The experimental approach taken was to study spontaneous lung metastases after removal of the primary tumour at 13 days after tumour cell inoculation. Both Nafazatrom and imidazole decreased the lung weight when given during the period either before or after the excision of the primary tumour. There was a general trend toward an increase in the number of small lung nodules (greater than 2 mm) and a decrease in large lung nodules (greater than 2 mm) as a result of the chemotherapy. Mean survival time of the mice was significantly different among the five groups, with the mice surviving the longest in the group treated with Nafazatrom after the excision of the primary tumour.     

New determinates of disease progression and outcome in metastatic ovarian carcinoma

Ovarian cancer is the most lethal gynecologic malignancy. This is attributed to frequent presentation at late stage, when the tumor has metastasized, as well as to development of chemotherapy resistance along tumor progression. Patients with advanced-stage ovarian carcinoma have widespread intraperitoneal metastases, including the formation of malignant serous effusions within the peritoneal cavity. Pleural effusions constitute the most frequent site of distant metastasis (FIGO stage IV disease). Unlike the majority of solid tumors, particularly at the primary site, cancer cells in effusions are not amenable to surgical removal, and failure in their eradication is one of the main causes of treatment failure. Our research in recent years has demonstrated that a large number of cancer-associated molecules are differentially expressed in effusions compared to primary carcinomas and solid metastases. We have additionally observed that expression of several of these molecules differs between primary diagnosis (pre-chemotherapy) and disease recurrence (post-chemotherapy) specimens, and that they are significantly associated with response to chemotherapy and patient survival. These observations are thought to be related to disease progression, as well as to the unique microenvironment of effusions, and may have impact on the selection of targeted therapy in this cancer. This review discusses our recent observations with respect to the biology of ovarian carcinoma cells in effusions, and focuses on the clinical role of tumor-associated molecules at this anatomic site.     

Absence of generalized immunosuppression in C57BL/6J mice implanted with Lewis T241 fibrosarcoma or Lewis lung carcinoma

Summary The immune status of C57BL/6J mice implanted with Lewis T241 fibrosarcoma or Lewis lung (LL) carcinoma was investigated on days 14 and 28 after implantation. Splenic lymphocyte responses were assessed in mitogen (Con A, LPS) mixed lymphocyte culture (MLC), natural killer (NK), graft-vs-host (GVH), and interleukin production assays. Except for NK-cell cytotoxicity, all other immunologic parameters were either comparable to those in medium-implanted controls or augmented. NK cytotoxicity was reduced in both tumor-bearing groups on day 28. The provision of NK potentiation therapy (-interferon, polyinosinic: polycytidylic acid) to T241 mice under various treatment conditions did not have any significant effect on lung metastasis or survival.The results of this study do not support the thesis that T241-or LL-bearing C57BL/6J mice are generally immunosuppressed. Indeed, when immune functions were assessed on the basis of total splenic activity, each of the measured immunologic parameters was substantially greater in animals with tumors than without. Further it seems improbable, considering the magnitude of the NK-cell defect in T241 mice on days 14 and 28 after implantation and the absence of a therapeutic response to NK-cell stimulants, that NK-cell cytotoxicity is intrinsically associated with resistance to tumor progression in this model.