摘要:

Sera from 26.7% of the clinically healthy chemical workers with occupational exposure to bladder carcinogens produced immunofluorescent staining of the intracellular antigens of an allogeneic transitional cell carcinoma of the bladder. The incidence of positives among normal donor’s and early stage bladder cancer patients was much lower, viz. 3.6 and 6.7%, respectively. The same sera were also tested for their staining reactions against surface antigens of bladder tumour cells. Again sera from a higher proportion of chemical workers (28.6%) was found to produce immunofluorescence compared with normal donors (12.6%) and bladder cancer patients (18.6%). The elevated incidence of antibodies among chemical workers’ sera was not due to autoantibodies which were similarly distributed in the 3 groups. Furthermore, the staining of chemical workers’ sera was not tumour type specific as all the sera which stained membrane or intracellular components were found to lose their staining ability on absorption with non-bladder tumour cells. It is proposed that these antibodies result from carcinogenic damage and have a physiological role to

ISSN:0030-2414    

DOI:10.1159/000225609

出版商:S. Karger AG    

年代:1982

数据来源: Karger

摘要:

Some tumors release factors able to activate host osteoclasts. Mithramycin at sub-tumoricidal doses inhibits the release of calcium mediated by osteoclasts. If invasion of bone by a cancer requires activation of these cells, their intermittent ‘blockade’ might impede the development of metastases to bone or their local extension. Fetal rat bones prelabelled with 45Ca were cultured in the presence of 10––7M prostaglandin E2, sera from normal individuals, or from patients with multiple myeloma. Additional samples preincubated for 3 h with 1 μg/ml of mithramycin, were washed before culture. Compared with controls, prostaglandin E2 stimulated the release of 45Ca by 28% (5 experiments) and mithramycin inhibited release by 15% (3 experiments). Pre-exposure to this cytotoxic antibiotic before culture withPGE2 reduced the augmented release. Sera from 4 patients with multiple myeloma were incubated with 45Ca-labelled bones, some pretreated with mithramycin. An additional 29% release of 45Ca (4 experiments) was prevented by mithramycin. These results are consistent with the hypothesis that augmented release of 45Ca due to stimulatory factors such as prostaglandins or factors in sera from patients with multiple myeloma can be partially inhibited by pretreatment with mithramycin. Possibly, intermittent blockade of host osteoclasts can impair formation of metastases to bone by cancers dependent upon their activation for this event, or reduce the extent of local invasion by established metastases. Modifying the behavior of a cancer by altering the host-response to factors which it releases represents a potential alternative to cytotoxic chem

ISSN:0030-2414    

DOI:10.1159/000225610

出版商:S. Karger AG    

年代:1982

数据来源: Karger

摘要:

A total of 59 infections were encountered in 29/46 patients with multiple myeloma (MM). Most infections arose in the urinary tract (31%), respiratory tract (29%), followed by blood (12%), oropharynx (12%), skin and soft tissue (7%). Gram-negative bacilli were identified in 51% of infections, most common being Enterobacteriaceae and Haemophilus influenzae. Gram-positive organisms were responsible for 7% of infections. 24% of patients with urinary tract infections had signs of cord compression. Absolute lymphopenia was common, and was seen in 65% of patients with urinary infections, 75% of respiratory infections, and 86% of septicemic patients. In contrast, granulocytopenia was mainly observed in patients with septicemia (71%), followed by those with respiratory infections (31%). All patients were on cytotoxic chemotherapy, and most were hypoglobulinemic. About one third of septicemias, and one half of urinary and respiratory infections, respectively, were hospital-acquired. Results indicate that the current pattern of infections in MM seems to favor gram-negative organisms. The role of predisposing factors in the pathogenesis of infections in these patients is discussed.

ISSN:0030-2414    

DOI:10.1159/000225611

出版商:S. Karger AG    

年代:1982

数据来源: Karger

摘要:

Some possible explanations are considered for the better response to surgical adjuvant chemotherapy in premenopausal than in postmenopausal breast cancer patients. Mean estrogen receptor (ER) concentration is lower in premenopausal women. It is proposed that ER-negative women tend to respond more favorably to chemotherapy for breast cancer because higher estrogen levels in this group may induce hydrolytic enzymes which break down the stromal barrier to the tumor, resulting in a less viscous, less fibrous stroma, and an increased vascular supply. These conditions may facilitate the diffusion of chemotherapeutic agents to the interior of a tumor. This hypothesis can be investigated utilizing existing data gathered in clinical trials of adjuvant chemotherapy.

ISSN:0030-2414    

DOI:10.1159/000225612

出版商:S. Karger AG    

年代:1982

数据来源: Karger

摘要:

Daily treatment of female Sprague-Dawley rats with CB-154 (prolactin suppressor) or Tamoxifen (estrogen antagonist) for 33 days before and after 7,12-dimethylbenzanthracene (DMBA) administration reduced (p < 0.05) the incidence of mammary carcinomas by 58 and 49%, respectively. A combination of CB-154 and Tamoxifen further reduced (p < 0.05) mammary carcinoma incidence by an additional 50–59%. Treatment with Tamoxifen for 66 days beginning 33 days after carcinogen treatment reduced (p < 0.05) the incidence of mammary carcinomas by 65%; CB-154 treatment, during the same time period, did not significantly effect the final yield of mammary carcinomas. The combination of Tamoxifen and CB-154 was comparable to Tamoxifen alone in suppressing the incidence of mammary carcinomas in the latter study. These results demonstrate a substantial suppressive and synergistic effect of Tamoxifen and CB-154 in the initiating phases of mammary carcinogenesis while in the early promoting phases of this oncogenic process, short-term treatment with Tamoxifen was superior to CB-154 treatment; no synergism between these clinically important compounds was observe

ISSN:0030-2414    

DOI:10.1159/000225613

出版商:S. Karger AG    

年代:1982

数据来源: Karger

摘要:

Regimens for the generation of a highly cytotoxic xenogeneic response, the mechanism of this response, and its effect on tumor cells were investigated in a rat antimouse tumor system. Fischer 344 rats were immunized with EL-4 lymphoma and the ability of the sensitized rat lymphocytes to suppress the local growth of four different C57BL/6 tumors was evaluated. Optimal sensitization of the rat was achieved using large numbers of viable tumor cells in a primary intraperitoneal immunization. Highly cytotoxic effector cells generated in this xenogeneic setting significantly suppressed the local growth of appropriate tumor targets. Rat T cells appeared to be the sole effector cell and their effect was abrogated by anti-rat immune responses in the host mouse. This rat anti-EL-4 model will allow further investigation into xenogeneic antitumor responses and their possible role in local immunotherapy.

ISSN:0030-2414    

DOI:10.1159/000225614

出版商:S. Karger AG    

年代:1982

数据来源: Karger

摘要:

To extend the information on the mutagenic effect of methylazoxymethanol (MAM) acetate, which has been established as a potent carcinogen, the frequency of sister-chromatid exchange (SCE) was determined in bone marrow cells of Sprague Dawley rats and in cultured rat lymphocytes. To get differentially stained chromatids under in vivo conditions, the rats received 5-bromodeoxyuridine adsorbed on activated charcoal intraperitoneally. Chromosomes were stained with fluorescence plus Giemsa. In this study a significant increase of SCE frequency after the application of various concentrations of MAM acetate could be observed both in vivo and in vitro.

ISSN:0030-2414    

DOI:10.1159/000225615

出版商:S. Karger AG    

年代:1982

数据来源: Karger

摘要:

Continuous administration of 0.0625% 1,2-diallylhydrazine dihydrochloride in drinking water for life to 6-week-old randomly bred to Swiss mice induced lung tumors. In comparison with the untreated controls, the lung tumor incidence rose from 25 to 80% in the females and from 26 to 80% in the males. The treatment had no apparent effect on the development of other tumor types. Histopathologically, the lesions were classified as adenomas and adenocarcinomas of the lungs. The work is a continuation of our structure activity inquiry concerning the relative carcinogenic potencies of the dialkyl versus the monoalkyl series of hydrazine analogues.

ISSN:0030-2414    

DOI:10.1159/000225616

出版商:S. Karger AG    

年代:1982

数据来源: Karger

摘要:

The modified steroidal alkylating agent, 3β-hydroxy-13α-amino-13,17-seco-5α-androstane-17-oic-13,17-lactam[p-[bis(2-chloroethyl)amino]-phenyl]acetate showed excellent activity in treatment of three murine solid tumors. Colon 26-bearing CD2F1 mice lived twice as long as controls with tumor free survivors at the end of the 70-day observation period. CD8F1 mammary tumor growth was suppressed greater than 90% compared to controls. B16 melanoma-bearing B6D2F1 mice lived 50% longer than controls. This agent had previously been shown to be active in treatment of the Theagenion-Bahner angiosarcoma, the T8 Guerin tumor, LI210 leukemia and P388 leukem

ISSN:0030-2414    

DOI:10.1159/000225617

出版商:S. Karger AG    

年代:1982

数据来源: Karger

摘要:

Lymphoid leukemia induced by 7,12-dimethylbenz(α)anthracene (DMBA) in rats and maintained by serial intraperitoneal transplantations in newborn rats was subjected to immunological and enzymological characterization. The Thy-1 antigen positivity rendered evidence for the T cell origin of the leukemia studied. Expression of cell surface complement binding receptors and patterns of cytoplasmic acid phosphatase and nonspecific acid α-naphthyl acetate esterase enzymes drew the attention to the dominance of lymphoblasts and prolymphocyte

ISSN:0030-2414    

DOI:10.1159/000225618

出版商:S. Karger AG    

年代:1982

数据来源: Karger