ISSN:0030-2414    

DOI:10.1159/000225218

出版商:S. Karger AG    

年代:1977

数据来源: Karger

摘要:

Chalones specifically inhibit cell proliferation not only in their respective normal cell system, but also in the malignant descendants of these cells. Consequently, a number of hypotheses have been put forward as to how chalones could be used in cancer treatment or related areas. As chalones are not cytotoxic themselves, but merely inhibit proliferation, the regression of tumors which has been observed in some cases must have been caused by other mechanisms, not directly related to the increased chalone level. Some of the potential advantages and drawbacks of this direct approach will be discussed. Some models in which chalones serve as adjuncts to other forms of therapy will be discussed. The experimental testing of these procedures and hypotheses is hampered severely by the unavailability of satisfactory chalone preparations. A possible approach to overcome this by using synthetic granulocytic (and possibly other) chalone(s) is discussed in detail.

ISSN:0030-2414    

DOI:10.1159/000225219

出版商:S. Karger AG    

年代:1977

数据来源: Karger

摘要:

Studies using inhibitors of DNA synthesis have shown that DNA polymerase a is located in nuclei of polyoma virus infected mouse cells to the same degree as these nuclei are engaged in DNA replication. These results indicate that either the enzyme is actively transported into nuclei concomitant with the onset of DNA synthesis, or that it is bound much more strongly in nuclei during DNA replication. In any case, these observations support the hypothesis that DNA polymerase a is involved in the replication of cellular and viral DNA.

ISSN:0030-2414    

DOI:10.1159/000225220

出版商:S. Karger AG    

年代:1977

数据来源: Karger

摘要:

The experiments described in this paper were performed in order to elucidate a possible regulatory role of acute and chronic myeloid leukemic leucocytes. The influence of these cells on either activated or non-activated mouse bone marrow cells was measured, and the results were compared with the action of the two major leucocyte fractions, mononuclear cells and granulocytes. It was demonstrated that acute leukemic blasts were almost completely unable to activate myeloid committed stem cells (Colony Forming Units, CFUc). In contrast, blasts from patients with chronic myeloid leukemia (CML) in blastic crisis disclosed a variable pattern of activation, in that two out of three cases exerted normal stimulatory capacity. A possible inhibitory action of leukemic cells was the subject of further experiments. Acute leukemic blasts in some cases disclosed inhibitory activity, a few cases appeared to be without influence on normal proliferating CFUc. Granulocytes from patients with CML in the chronic phase showed inhibitory capacity when compared with granulocytes from normal individuals.

ISSN:0030-2414    

DOI:10.1159/000225221

出版商:S. Karger AG    

年代:1977

数据来源: Karger

摘要:

Previously PHA-stimulated isolated human lymphocytes were infected with HSV-2. The 3H-thymidine uptake measured 7 h and 29 h p.i. showed a marked reduction of incorporation of the radioactive material. Electron microscopy of those cells 25 h p.i. permitted the detection of naked nucleocapsids inside the nuclei and protein coated nucleo-capsids in the cytoplasm. The importance of HSV-2 multiplication in human lymphocytes in connection with chronically recurring infections is discussed.

ISSN:0030-2414    

DOI:10.1159/000225222

出版商:S. Karger AG    

年代:1977

数据来源: Karger

摘要:

The influence of environmental carcinogens on the developing embryo has been investigated using SWA mice as models and 1 -ethyl-1 -nitrosourea (ENU) as the carcinogen. The percentage of tumor development among the F1 generations of siblings delivered and nursed by mothers treated with ENU was higher than that of the F1 generations of siblings delivered of treated mothers but nursed by untreated foster mothers. The presence of multiple tumors was also more frequent in this group compared to the siblings which were exposed only transplacentally to ENU. The second generations also developed malignant tumors. Two successive generations of siblings which were delivered of untreated mothers but nursed by foster mothers treated with ENU on the 12th day of pregnancy, showed a higher percentage of tumors when compared to the control group. This result is of great significance as the siblings were not exposed to the carcinogen transplacentally, and the foster mothers were treated with only a single dose of ENU long before the lactating period, namely, on the 12th day of pregnancy.

ISSN:0030-2414    

DOI:10.1159/000225223

出版商:S. Karger AG    

年代:1977

数据来源: Karger

摘要:

A continuously growing cell line, established from a bronchial carcinoma of squamous cell type derived from a 56 year old white male, has been kept in culture since 1971. The line, named E14, is now in its 158th passage. Cytogenetic analysis demonstrates a slight gain of chromosome number up to the 100th passage, since when the stem-line has remained fairly stable at between 58 and 61 chromosomes. Banding analyses indicate that, whereas minor changes in the structural rearrangements of the karyotype are constantly occuring, the basic tumor genotype remains fairly stable.

ISSN:0030-2414    

DOI:10.1159/000225224

出版商:S. Karger AG    

年代:1977

数据来源: Karger

摘要:

Lewis lung tumor (LLT) passaged in F1 hybrids of the original C57B1/6 strain, where it arose spontaneously, is rejected by allogeneic SWA (Swiss albino) mice. However, aggregation chimeras derived from these SWA mice and the F1 hybrids of C57B1/6 developed an increased growth of primary tumor and reduced number of metastases when compared with the F1 hybrids. In the present study LLT passaged in C57B1/6 mice is not rejected by SWA mice. It is demonstrated that in aggregation chimeras now derived from two strains both taking the tumor, primary tumor growth was enhanced and the number of metastases reduced as in the former experiment. The tendency of reactions of lymphatic organs in chimeras to tumor burden was comparable with the SWA and F1 hybrid (C57B1/6 x SWA and SWA x C57B1/6) recipients’ response. Furthermore, chimeras had the highest spleen enlargement. Possible alternations in immune functions of chimeras due to their differing genotype combination are discussed in the LLT mode

ISSN:0030-2414    

DOI:10.1159/000225225

出版商:S. Karger AG    

年代:1977

数据来源: Karger

摘要:

The anti-tumor effect of vitamin A and/or BCG was investigated in Lewis lung tumor system. Tumor growth and lung metastases were significantly suppressed, when tumor cells were mixed with BCG and inoculated subcutaneously into vitamin A-treated animals. Survival time was also prolonged by the same treatment. Vitamin A alone, without BCG, showed no effect on tumor growth, lung metastases or survival time.

ISSN:0030-2414    

DOI:10.1159/000225226

出版商:S. Karger AG    

年代:1977

数据来源: Karger

摘要:

The lymphocytes of patients with inoperable bronchus carcinoma were investigated for their in vitro reactivity toward tumor-associated antigens. The leucocyte-migration-inhibition-test (LMIT) was applied using formalinised tumor cells and tumor cell hybrid cell lines. 34 patients with inoperable squamous cell carcinoma of the lung and 21 healthy controls were tested for their leucocyte sensitisation to these cells. 55 % of the patients with lung cancer showed a specific LMI toward the E-14 cell line, (an established cell line from a human squamous cell carcinoma of the lung), compared to only 9 % of the controls. There was about the same percentage of specific reactions of the lymphocytes to three different hybrid cell lines which have only a few human chromosomes left over. There was no reactivity to the parental hamster fibroblasts. It is assumed that the hybrid cells carry the same tumor-associated antigens on their cell surfaces as the E-14 tumor cells.

ISSN:0030-2414    

DOI:10.1159/000225227

出版商:S. Karger AG    

年代:1977

数据来源: Karger