摘要:

Hormonal responsiveness should be considered in terms of at least three homeostatic constraint mechanisms. Observations on the induction of specific responses in rat prostate reveal that certain of these are controlled differentially, and also that immature cells can be modified by low levels of androgen. The conditioning effect of low levels of steroid is further demonstrated by the benefits of fractional hormone‐replacement therapy in controlling and delaying tumor progression. A revised approach to endocrine therapy of cancer should be seriously considered. This would entail the fractional replacement of hormone after ablative surgery.

ISSN:0098-4108    

DOI:10.1080/15287397809529667

出版商:Taylor & Francis Group    

年代:1978

数据来源: Taylor

摘要:

Glucocorticoids are widely used for therapeutic purposes and have many toxic side effects. It seems likely that their physiological, therapeutic, and toxic effects are exerted through similar receptors and may be inherently inseparable. Lymphoid cells are targets for all these effects. With rat thymus cellsin vitro, glucocorticoids immediately bind to cytoplasmic receptors, which are translocated to the nucleus, where they apparently induce messenger RNA for specific proteins that rapidly inhibit glucose transport. Protein and RNA metabolism are inhibited more slowly and eventually the cells die. The rate of formation of nuclear complexes and the timing of the hypothetical RNA‐synthetic step are such as to suggest that the hormone‐receptor complexes stimulate RNA synthesis in proportion to the rate at which they bind to nuclear sites rather than in proportion to the number of nuclear sites occupied.

ISSN:0098-4108    

DOI:10.1080/15287397809529668

出版商:Taylor & Francis Group    

年代:1978

数据来源: Taylor

摘要:

The hypothesis that the growth of mammalian cells is regulated by hormones is now supported by considerable evidence. Two rat pituitary cell lines, GH3and GC, a mouse melanoma, M2R (B16), and a human cervical carcinoma cell, HeLa S‐3, have been grown indefinitely in serum‐free (SF) hormone‐supplemented medium. No visible changes of growth characteristics were observed in the cells grown continuously in the SF condition. However, changes in the activity of a plasma membrane enzyme, alkaline phosphatase, and in the relative intensity of surface proteins that are labeled by the [125l] lactoperoxidase technique were found in HeLa cells grown in the SF condition.

ISSN:0098-4108    

DOI:10.1080/15287397809529669

出版商:Taylor & Francis Group    

年代:1978

数据来源: Taylor

摘要:

A technique for culturing primary explants of rabbit endometrial cells in chemically defined medium has been developed. Diethylstilbestrol and natural estrogens were found to increase the rate of DNA initiation while progesterone had the opposite effect.

ISSN:0098-4108    

DOI:10.1080/15287397809529670

出版商:Taylor & Francis Group    

年代:1978

数据来源: Taylor

摘要:

The production of mouse mammary tumor virus (MTV) is stimulated by treatment of mammary carcinoma cells with glucocorticoid hormones (e.g., dexamethasone). The reaction appears to be a primary and receptor‐mediated phenomenon in which the rate of synthesis of MTV RNA is selectively increased; the maximally induced rate is reached within 15 min after addition of the hormone. Production of MTV RNA is also stimulated by dexamethasone in some but not all clonal isolates of nonmurine cells infected by the virus. Using restriction endonucleases, we have characterized both integrated and unintegrated viral DNA from clones of infected rat hepatoma (HTC) cells. We suggest that the site(s) in the rat cell genome into which MTV DNA integrates may be a determining factor for MTV RNA synthesis.

ISSN:0098-4108    

DOI:10.1080/15287397809529671

出版商:Taylor & Francis Group    

年代:1978

数据来源: Taylor

ISSN:0098-4108    

DOI:10.1080/15287397809529672

出版商:Taylor & Francis Group    

年代:1978

数据来源: Taylor

ISSN:0098-4108    

DOI:10.1080/15287397809529656

出版商:Taylor & Francis Group    

年代:1978

数据来源: Taylor