Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0027651 (tumor)
 685,946 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

High dosage MAP (medroxyprogesterone acetate) was used in the treatment of very advanced breast cancer. 25 patients were included in the study all of whom had measurable lesions which had been unsuccessfully treated by other methods, hormonal or combination chemotherapy. Tables present information on previous treatments, results of pre-MAP therapy examinations, and results of post-MAP therapy examinations. Treatment dosage is explained. Results with this high MAP-dosage therapy compare favorably with the rate of remission obtained through other primary hormonal therapies by other researchers. Promising results without noteworthy adverse effects were obtained; remissions, however, were short. 7 of the 25 had partial remission with a median duration of 5+ months. Another 7 patients obtained a stationary status of the disease. Even some patients who had not responded previously to Tamoxifen achieved partial remission with MAP therapy, indicating that the MAP does not operate directly on the tumor cells. The incidence of partial remissions was not adversely affected by previous combination chemotherapy and hormonal treatment. Acceptability of the treatment was good.
 ...
PMID:High dose medroxyprogesterone-acetate treatment in advanced mammary carcinoma. A phase II investigation. 16 70

Since metastasizing breast cancer is hormone-related, hormonal therapy is based on control of tumor growth by elimination of the hormonal influence, hormone ablatives, or administration of steroid hormones to change the hormonal milieu of thehost organism. The time span during which hormonal therapy may be effective is extremely limited; therefore, this is not recommended for patients with an interval of less than 2 years between primary treatment and 1st manifestation of metastasis, patients with visceral metastasis, or women less than 5 years in the postmenopause. According to cooperative European and American studies remission rates for different types of endocrine therapy include: ovariectomy, 25-40%; adrenalectomy, 30-40%; hypophysectomy, 30-40%; androgen, 20%; and estrogens, 20-35%. Studies are underway concerning the use of antiestrogens (Nafoxidine and Tamoxifen) andinhibition of prolactin secretion. Investigations have shown that patients with proven estrogen receptors in the tumor tissue are particularly responsive to hormonal therapy. For patients with no determinable estrogen receptors, however, chemotherapy is perferable. Ovariectomy is recommended as the 1st measure for women in the premenopause, hormone additives for women longer than 5 years in the postmenopause, and for women in the 1st years after menopause ovariectomy in combination with a form of polychemotherapy. For patients with short free intervals polychemotherapy with another endocrine measure, for pleuracarcinosis and liver metastosis high corticosteroid dosages, and for metastases in the central nervous system radiatio treatment with high corticosteroid dosages are recommended.
 ...
PMID:[Hormone therapy of breast cancer]. 18 Mar 75

The effect of prolactin in supporting the growth of 7, 12-dimethylbenz(a)anthracene-induced mammary tumor in adult female Sprague-Dawley rats was investigated when estrogen receptors were blocked by the nonsteroidal antiestrogen, Tamoxifen, ICI 46,474. Following an oophorectomy-induced remission, perphenazine, which stimulates endogenous prolactin release, was able to restore tumor growth whether or not Tamoxifen was added. A second course of perphenazine treatment, instituted after the tumors were allowed to shrink, was again effective in stimulating tumor growth. After a regression in tumor size induced by oophorectomy and daily administration of Tamoxifen, perphenazine was able to restore original tumor size despite continued treatment with Tamoxifen. In intact rats, after regression was obtained by daily administration of Tamoxifen and the prolactin inhibitor, lergotrile mesylate, perphenazine induced tumor growth when the latter was discontinued, even though Tamoxifen was continued for 50 days. Estrogen receptors measured at the time of maximum stimulation by perphenazine were undetectable. On the other hand, estradiol did not stimulate tumor growth when serum prolactin was depressed to undetectable levels by lergotrile. These results indicate that prolactin supports the growth of 7, 12-dimethylbenz(a)anthracene-induced rat mammary tumor and that estrogen receptors are not required under these conditions.
 ...
PMID:Predominant role of prolactin in stimulating the growth of 7, 12-dimethylbenz(a)anthracene-induced rat mammary tumor. 19 Nov 82

Tamoxifen is a synthetic nonsteroidal drug with antiestrogenic properties. This report describes the response of patients with metastatic breast cancer to tamoxifen and correlates clinical responses with tumor tissue content of cytoplasmic estrogen binding proteins (EBPs) and other biochemical parameters. Ages of patients ranged from 27 to 82 years. 7 patients were premenopausal, 63 postmenopausal, and 2 had recent endocrine ablaetion. Prior hormone therapy, radiotherapy, or chemotherapy ahd been given to all patients. Tamoxifen was given at a dose of 20 mg orally for a minimum of 4 weeks and continued if an objective remission was shown. Before therapy a biopsy specimen was taken for determination of EBP and for specific enzyme activities. Another biopsy specimen was taken for at least 8 weeks after therapy. A total of 72 patients were treated for at least 4 weeks. The overall response rate was 38%. Most frequent responses were in the over-70 age group. The median duration of response has been 9.5 months. Bony involvement responded to therapy in 21 of 28 patients. No responses were shown in 6 patients with liver metastases. Only 1 of 18 patients who had previous chemotherapy responded. Of 31 who had no prior chemotherapy, 73% achieved a remission. There was a 44% correlation between patients with a positive EBP assay and response to therapy, but none in EBP-negative patients. In this study 20 of 28 patients had normal arylsulfatase B/DNA ratios in their tumor tissue and 11 of the 20 responded to tamoxifen therapy. Patients who responded most favorably to therapy had normal G-6-PD activities. It is concluded that tamoxifen therapy may cancel the need for ablative surgery in postmenopausal patients with positive EBPs and who have had a prior response to additive hormonal treatment.
 ...
PMID:Therapeutic use of tamoxifen in advanced breast cancer: correlation with biochemical parameters. 19 Nov 85

The number of plasma membrane receptors for TRH on tumor-derived mammotropic cells in culture, GH3 and GC cells, but not their affinity for TRH, was increased by estrogens. For GH3 cells, exposure to 10 nM 17 beta-estradiol for 48 h increased the receptor level from 54,000 to 90,000 sites/cell, while for GC cells, the number of receptors increased from 29,000 to 46,000 after 28 h. PRL accumulation in the medium was also increased by 17 beta-estradiol. 17 beta-Estradiol and diethylstilbestrol were equally potent in increasing the TRH receptor level, while estrone was only 1/10th as potent. Diethylstilbestrol bound to the cytoplasmic estrogen receptor with an apparent affinity approximately 2.5 times higher than 17 beta-estradiol in GH3 and GC cells, while the affinity for estrone was only 1/12th to 1/20th that of 17 beta-estradiol. Tamoxifen, an antiestrogenic compound, inhibited the increase in TRH receptor number induced by 0.3 nM 17 beta-estradiol and was capable of binding to the estrogen receptor. Modulation of the TRH receptor level on mammotropic cells by estrogens, which is likely mediated through cytoplasmic estrogen receptors, may be an important mechanism for regulation of TRH action.
 ...
PMID:Estrogens increase the number of thyrotropin-releasing hormone receptors on mammotropic cells in culture. 22 Nov 99

The antiestrogen Tamoxifen (T), given orally to 113 patients with stage IV breast cancer, induced objective remission in 50%. Duration of remission in the first 39 patients, with minimum 27 months follow up, is 18 + months; these results are equal to those of surgical hypophysectomy. T prolonged survival in responders. Older age, previous response to endocrine therapy and positive estrogen receptors predicted response to T. T was effective in hypophysectomized patients in whom serum growth hormone and prolactin were undetectable, but serum ostrogens were present in low amount, suggesting a direct stimulatory effect of estrogens at the tumor level. Hypophysectomy induced further palliation after treatment with T, indicating that pituitary hormones may also play a role in the growth of some human breast cancers. Side effects from T were minimal. T is the initial treatment of choice for postmenopausal women with hormone responsive stage IV breast cancer.
 ...
PMID:Antihormone treatment of stage IV breast cancer. 42 Nov 71

Transsphenoidal hypophysectomy was performed in 212 consecutive patients with metastatic breast cancer: 11 died within 30 days, two of surgical complications and nine of advanced metastatic disease. Two patients were unevaluable because of inadequate follow-up in one and simultaneous radiation treatment in the other. Of 199 evaluable patients 42% had an objective remission. Duration of remission averaged 18+ months with 10 out of 84 patients still in remission. Presence of estrogen receptors in the tumor significantly predicted response to hypophysectomy. Of 156 patients in whom completeness of hypophysectomy was assessed, 128 were thought to have a complete removal as shown by the fact that their growth hormone and prolactin were undetectable after stimulation with arginine or chlorpromazine, respectively. Of 26 patients in whom TRH test was performed, TSH and prolactin were undetectable in 20. Of 23 patients where autopsy was performed only six had microscopic pituitary tissue remaining. Hypophysectomy induced remission in eight of 15 patients who had previously responded and then relapsed to the antiestrogen Tamoxifen and in four of 17 who had failed. Conversely, antiestrogen therapy induced remission in six of 26 patients who had previously responded to hypophysectomy and in whom serum estrogens were present in small amount. These data indicate that both gonadal and pituitary hormones play a role in the growth of some human breast cancers.
 ...
PMID:Transsphenoidal hypophysectomy in breast cancer: evidence for an individual role of pituitary and gonadal hormones in supporting tumor growth. 50 1

Tamoxifen (ICI 46474), an antiestrogen, was given to 89 selected patients with stage IV breast cancer at a dose of 20 mg orally every 12 hours. Forty-seven percent of the patients had objective tumor regression averaging 11+ months with 25 of 42 women still in remission. In the first 39 patients where the minimum follow-up period is 16 months the average duration of remission is more than 15 months with 8 of 19 patients still in remission. These results are approaching those of surgical hypophysectomy, where, in our experience the average remission lasts about 18 months. Thus, Tamoxifen is a highly effective antitumor agent and is probably the initial treatment of choice for women with hormone responsive breast cancer. Antiestrogen induced objective remissions in 5 of 19 patients who had previously responded to surgical hypophysectomy, and 5 additional patients showed no progression of disease lasting 15+ months. Estradiol and estrone were detectable in the serum of these patients whereas, prolactin and growth hormone were not detectable. Thus, antiestrogen can induce remissions in some patients in the absence of the pituitary gland, and this constitutes additional palliation and provides evidence that estrogens can directly stimulate tumor growth. Four of 7 patients who obtained remissions from Tamoxifen obtained further improvement from hypophysectomy, and 1 of 8 patients who failed to benefit from antiestrogen improved after hypophysectomy. These results suggest that prolactin and growth hormone may also play a role in stimulating tumor growth in some patients.
 ...
PMID:Treatment of breast cancer with antiestrogen: approach to medical hypophysectomy? 61 66

The detection of specific hormone receptors in normal and tumor tissue has brought new insight into the mechanisms of action of hormones and anti-hormones. The Swiss Cooperative Cancer Study Group (SAKK) has evaluated the antitumor effect of the new antiestrogenic substance tamoxifen in metastatic breast cancer. 158 postmenopausal patients treated with 20 mg/d tamoxifen by mouth are evaluable at present time. Complete and good partial remissions were achieved in 39 patients (25%) largely with soft tissue but also lung and bone metastases. Tamoxifen was well tolerated and caused few serious complications such as thrombosis/pulmonary embolism and hypercalcemia. These results confirm already published experience with tamoxifen, which may replace the estrogens as the primary endocrine treatment in postmenopausal mammary carcinoma metastasizing to soft tissues, lung and bone.
 ...
PMID:[Antiestrogens: a new endocrine treatment possibility in metastasizing breast neoplasms. Experiences of the Swiss Cooperative Cancer Study Group with tamoxifen]. 69 81

This paper reviews the antiestrogenic and antitumor properties of tamoxifen (NSC-180973; ICI-46474) in the rat. In classic tests for antiestrogenic activity, tamoxifen inhibits the actions of estradiol in the rat uterus and vagina. At the cellular level, tamoxifen inhibits estrogen binding to cytoplasmic estrogen receptors, but although estrogen-receptor units are translocated to the nucleus DNA synthesis does not occur. It is suggested that tamoxifen competes for estrogen receptors in the cytoplasm and the false messenger units block the nuclear acceptors which are normally activated by estradiol-estrogen receptor complexes thereby provoking DNA synthesis. Tamoxifen inhibits the growth of some 7.12-dimethylbenz(a)anthracene-induced rat mammary tumors whereas others continue to grow. Estrogen-stimulated rises in plasma prolactin are only partially inhibited by tamoxifen although at the tumor level, tamoxifen completely blocks estrogen binding. There is a linear correlation (P less than 0.01) between estrogen-receptor levels in tumor biopsies before therapy and tumor responses to 3 weeks of tamoxifen treatment (50 mug/day) i.e., tumors with low levels of estrogen receptors do not respond to therapy whereas tumors with higher levels of estrogen receptors regress. It is suggested that tamoxifen antagonizes the actions of estrogen at the tumor level by blocking the estrogen-receptor mechanism thereby producing tumor regression. Therefore, estrogen-receptor measurements in tumor biopsies before therapy may be a useful predictive test for the tumor response to tamoxifen treatment.
 ...
PMID:Antiestrogenic and antitumor properties of tamoxifen in laboratory animals. 82 17


1 2 3 4 5 6 7 8 9 10 Next >>