Showing papers on "Cancer cell published in 1969"

Immunotherapy of Malignant Disease

Abstract: The importance of host resistance and immunological factors in influencing the growth of tumors has been suspected for over 50 years. 1 A great deal of experimental evidence has accumulated in the past two decades to support this thesis, and further studies in the immunologic field are now warranted on the basis of this evidence. The mechanisms by which host cells inhibit cancer growth or destroy cancer cells is not completely understood. Much of the early experimental work was concerned with attempts to demonstrate circulating antibodies against malignant tissues, identify specific tumor antigens, and develop effective cancer vaccines. In 1953, Foley 2 demonstrated specific antigenicity in a class of experimentally induced tumors induced by methylcholanthrene in syngeneic mice. He demonstrated that the removal of a growing transplant of an induced tumor was followed by resistance to subsequent challenge with the same tumor. These experiments have been confirmed many times and

Homogeneous cultivation of animal cells for the production of virus and virus products

Abstract: Homogeneous technique facilitates the cultivation of large quantities of cells, reduces the risk of contamination by eliminating many manipulations, and makes practical the control of conditions such as pH and oxygen tension. Although most animal cells will not multiply in free suspension, certain cell lines have lost the requirement of being attached to a solid surface. These cells can be subcultured indefinitely but have some resemblance to cancer cells such as their abnormal karyotype. Certain cell linen developed from human embryonic tissue maintain their diploid character after repeated subculture and would seem to be ideal for the production of vaccines. However, strict regulations exist for viral products for human injection in that only cells taken from normal tissue and subcultured but once may be used. A microcarrier method in which cells adhere to DEAE-Sephadex beads permits a suspension culture which may be termed quasihomogeneous. The attached cells may be retained by sedimentation or by screening as the medium is replaced. Cell debirs from the original tissue is difficult to remove from microcarrier cultures; modifications of the trypsinization technique have alleviated but not solved this problem. Conditions for virus replication can be less critical than those for cell growth in that oxygen tension seems to have little influence on virus production. In cases where rate of virus production increases with specific growth rate of cells, homogeneous culture would have a advantage in maintaining a high cell mogeneous culture would have a valuble advantage in maintaining a high cell growth rate for a longer time. Some virus infections destroy cells, but others cause little change in cellular mteabolism except that virus is continually produced. The latter type can be conducted with a microcarrier in continuous culture with a virus titer exceeding 107 plaque forming units per milliliter for over 50 days with Rubella-infected BHK cells.

Acquired Hormonal Dependence of Milk Protein Synthesis in Mammary Carcinoma Cells

Abstract: In order to study how mechanisms which control hormone-dependent genetic expres-sion may be altered in cancer cells, the synthesis of specific milk proteins by cells of the R3230AC mammary carcinoma was measured. Synthesis of 32P-casein components and lactose synthetase activity can be detected in these cells. 17β-Estradiol interacts with R3230AC mammary carcinoma cells to augment lactose synthetase activity and increase the rate of casein synthesis 3- to 4-fold. The relative rates of synthesis of the various casein components after estradiol treatment are similar to those observed in lactational cells. However, the absolute levels of casein synthesis and lactose synthetase activity in the stimulated cells were only 10% of those of normal lactational cells, reflecting a possible interplay between an altered growth regulatory mechanism and the mechanisms which control genetic expression in normal cells. Studies which compared the hormonal requirements for milk protein synthesis in normal and neoplastic cel...

Quantitative Studies on Cancer Dissemination

Abstract: Summary This paper describes an approach to estimating in a quantitative way the cancer cells present in blood and tissues of tumor-bearing animals. By using two transplantable tumors of mice, i.e., Ehrlich carcinoma and Sarcoma 180, in the ascites form, a relationship compatible with linearity was observed between the logarithm of cancer cells and either the weight of the tumor or the probit of the percent of tumor take. The number of cells necessary to obtain 50% of takes was considerably different when the cancer cells were included in fragments of different tissues or in the blood clot. The number of cancer cells present at 7 and 12 days after transplantation in the blood and lung of mice bearing an intracerebral tumor was calculated by using the proposed method.

Immunological studies on the membrane systems of cancer cells. 3. Immunospecificities of the mitochondria from virus-induced tumors by the precipitin reaction in agar gel

Abstract: The mitochondrial, the microsomal, and the supernatant fractions were prepared from the cell homogenate of tumors induced by viruses, such as adenovirus type 12, SV 40, and Rous sarcoma virus, etc. and the antigenicities of these fractions were investigated. In the virus-induced tumors, there existed no antigenicity common to the mitochondrial and the microsomal fractions as in the tumors induced by chemical carcinogens, and the highest antigenicity was recognized in the mitochondrial fraction. Therefore, the properties of the tumor cell mitochondria were precisely investigated with virus-induced tumor mitochondria. 1. The mitochondria of tumors induced by viruses have clearly the specific antigenicity. 2. This specific antigenicity of virus.induced tumor mitochondria IS common to all the virus-induced tumors used in the present study. 3. This tumor mitochondria.specific antigenicity is found commonly in all the tumor mitochondria in the present experiments. 4. The specific cancer antigenicity of tumor cell mitochondria does not exist in normal organ mitochondria, but the regenerating organ mitochondria exhibit a slight antigenicity common to cancer cell mitochondria.

Histochemical Studies on N-acetyl-β-galactosaminidase and N-acetyl-β-glucosaminidase in the Cancer of the Uterine Cervix

Abstract: N-acetyl-β-galactosaminidase (β-GA) and N-acetyl-β-glucosaminidase (β-GL) were histochemically studied on the cervix of myoma uteri and the cervix of the uterine cervical cancer, both resected immediately after hysterectomia. The results were compared with those of the CPL classification on the same specimen.1) Activities of neither β-GA nor β-GL were shown in the normal squamous epithelium and subepithelial tissue, but weak activity of β-GA and moderate activity of β-GL were shown in the columnar epithelial cells. 2) Cells showing the activities of β-GA and β-GL were seen in the parenchyma and adjacent tissue of the cervical cancer. These cells seemed to be mast cell judging from the comparison with the enzyme histochemical staining, H. E. staining and toluidine blue staining with the serial sections. 3) On the number of cancer cells showing the activities of β-GA and β-GL in the cancer tissue, no particular relation was found among the groups in the CPL classification. 4) In the adjacent tissue of cancer, the numbr of cells showing the activity of β-GL was markedly increased in C type of the classification and was moderately increased in CP type. In P type, however, the cells showing the activity of β-GL were not found at all or found scarcely in the preparations. Therefore, the classification by the quantity of the enzyme in the adjacent tissue of cancer was closely related to the CPL classification. The classification by the number of the cells showing the activity of β-GA had also some relation to the CPL classification, but the relation was not so close as that between β-GL and the CPL classification.

Antitumor factors of regional lymph node cells in the transplantation of Ehrlich ascites tumor cells. II. Properties of antitumor factors.

Abstract: With the purpose to elucidate further the properties of the supernatant F4 obtained by centrifugation at 100, 000 g from the regional lymph node cells of the Cb mice sensitized with EHRLICH ascites tumor cells, the supernatant (cf. Report 13) was subjected to the following treatments:. The supernatant (F4) was first diluted variously with Hanks solution. 2. F4 was passed through Seitz filter. 3. Heated at 56°C for 30 minutes. 4. It was frozen and thawed. 5. Treated with O. 01 96 trypsin solution. Each of F4 frations so treated was used in the tissue culture of JTC-II cells (derived from EHRLICH cancer cells) as target cells. As a result we found that the antitumor factor passes th rough Seitz filter, and it loses its antitumor activity by 4-fold dilution or over. Likewise F4 loses its activity by freezing-thawing treatment as well as by trypsin treatment, while by heat treatment at 56°C for 30 minutes, it still retains its activity. From these finding, it is assumed that the antitumor factor contained in F4, fraction is not serum antibody but is a protein associated with the cell membrane.

Immunological studies on the membrane systems of cancer cells. II. Immunochemical specificity of the mitochondria from chemical carcinogen induced carcinoma cells.

Abstract: As the results of investigating the antigenicities of various fractions from the membrane systems of cancer cells, it has been found that the remarkable cancer-specific antigenicity exists in cancer cell mitochondria With a particular reference to this antigenicity of cancer cell mitochondria, the antigenicities of the mitochondria of various kinds of rat ascites tumors and those of tumor-bearing rat liver mitochondria have been compared with those of normal rat liver mitochondria In addition, it has been demonstrated that a strong tumor antitransplantability is induced when the recipient rat is immunized with the tumor cell mitochondria In order to support these experimental facts, enzymatic activities of cancer cell mitochondria have been investigated also biochemically after treating the mitochondria with the antiserum to these mitochondria 1 The most remarkable cancer specific antigenicity exists in mitochondria among the membrane systems of cancer cells This cancer mitochondria-specific cancer antigenicity is common to all the ascites tumor mitochondria used here 2 The original tissue- or organ-specific antigenicities diminish or disappear at the carcinogenic transformation of cells 3 The tumor-bearing-organ specific antigenicity appears in the organs of animals bearing tumor 4 The tumor antitransplantability is acquired when rats are immunized with these tumor cell mitochondria 5 The inhibition of mitochondrial ATP·ase and respiratory activities is observed when the cancer cell mitochondria are treated with the anti serum to the mitochondria