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Query: UMLS:C0027651 (tumor)
 685,946 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

(MPA) Medroxyprogesterone acetate when employed at high doses (5001000 mg/day intramuscularly) can produce objective remission with improved survival in about 30% of postmenopausal women with advanced breast cancer resistant to cytotoxic drugs and endocrine therapies. When administered to women not previously treated with chemotherapy, the objective remission response rate reached 40%. From available evidence, high dose MPA can be considered a useful agent in the treatment of advanced breast cancer in postmenopausal women with soft tissue, pulmonary, pleural, or osseous involvement even when patients have become refractory to prior hormone and cytotoxic therapies. Early results suggest that the response rate can be increased in patients with estrogen-and/or progesterone-positive receptors. It is noteworthy that in a study conducted on postmenopausal women resistant to cytotoxic and/or hormonal drugs, the median duration of survival was 13.5 months, while CRs and PRs did not reach the median at 24 months after beginning MPA treatment. High dose MPA is essentially devoid of major side effects. Relief of pain, increase in appetite, and body weight, and sense of wellbeing are characteristic features of the improved quality of life under MPA treatment. However, a gluteal abscess (from 2-20% dose-related) is the most frequent side effect. A promising area for future studies is combined therapy using hormonal and cytotoxic agents or alternating sequential combinations. Well-designed studies are needed to develop means for increasing the complete response rate and therefore survival. Recent studies of combined chemotherapy and hormonal (MPA) therapy have yielded objective tumor regressions of 53-80% with an increased rate of complete remissions and duration of response. (Author's modified)
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PMID:High-dose medroxyprogesterone acetate (MPA) treatment in advanced breast cancer. A review. 39 Jul 98

The hamster ductus deferens cloned tumor cell line (DDT1) has been shown to contain both androgen and glucocorticoid binding activity. The androgen receptor binding site concentration is 1.07 x 10(-13) mol of testosterone/mg protein, and testosterone (T) binds with a Kd of 4.3 x 10(-10) M. Dihydrotestosterone (DHT) is also bound to the receptor with a Kd of 2.99 x 10(-10) M and the binding site concentration is 1.33 x 10(-13) mol/mg protein. The order of steroid binding affinity is DHT greater than T greater than Estradiol greater than Progesterone. Cortisol, dexamethasone, and triamcinolone acetonide do not inhibit the androgen binding in vivo or in vitro. In a cell free system antiandrogens inhibit the binding of DHT. The DDT1 cells have a separate receptor for cortisol which binds at saturation 3.44 x 10(-13) mol cortisol/mg protein and has a Kd of 4.54 x 10(-9) M. These studies provide evidence that these endocrine target cells contain specific high affinity receptors for more than one type of steroid. The glucocorticoid receptor may be important for maintaining essential undifferentiated functions while the DHT receptor gives the specific characteristics of sex hormone responsive tissues.
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PMID:The coexistence of androgen and glucocorticoid receptors in the DDT1 cloned cell line. 40 58

Proliferating tumor cells obtained from ovarian, mammary, and endometrial tumors in tissue culture were tested for the influence of proteohormones and steroid hormones on cellular DNA synthesis and cell growth. The gonadotropic hormones stimulated DNA synthesis of ovarian tumor cells by single administration, or in combination with cortisol, up to the 11-fold of the comparable controls. The hormone sensitivity of the cell lines was variable, resulting in individual reaction patterns. There was no correlation to the histological diagnosis of the primary tumors with respect to the grade of differentiation. The results suggest that ovarian tumor cells in tissue culture can maintain sensitivity to organotropic hormones. Compared to the ovarian carcinoma lines, mammary or endometrial tumor cells did not respond to a similar extent. Progesterone decreased DNA synthesis of endometrial carcinoma cells.
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PMID:Hormone sensitivity of gynecological tumor cells in tissue culture. 47 69

Endocrine hormone treatment has been found to be effective in treating metastatic breast cancer in 20-40% of the cases. The effectiveness of this treatment can be predicted to a certain extent by determining whether the hormone receptors in the tumor tissue react positively or negatively when incubated with highly active hormones, e.g. H3-17 beta-estradiol. Estrogen receptors are found in 60-70% of primary tumors and 40-50% of tissue samples from metastatized tumors. Estrogen receptors are more frequently found in post-menopausal women than in women who are still menstruating. Progesterone receptors have been found in 20-40% of all investigations undertaken, androgen receptors in 20-30%, and corticosteroid receptors in 20-50%. A remission rate of 56% has been achieved after endocrine therapy of those with positive estrogen receptor tests, compared to 10% among those with negative tests. The correlation between the receptor test results and (the success of) endocrine therapy is not very high; this could be a factor determined by the cellular constitution of a tumor. The remission rate is 75% among patients with positive receptor tests for both estrogen and progesterone. Faulty lab techniques could be responsible for low correlation. Determination of the receptor activity of both the primary tumor and its metasases, or immunological or immunohistological determination of receptor activity may improve the usefulness of the test in determining tumor reaction to endocrine hormone treatment.
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PMID:[The clinical value of hormone receptors in the treatment of breast neoplasms]. 54 83

Estrogen receptors (ER) were measured on specimens taken from 27 patients with benign breast conditions and 109 patients with breast cancer. Using sucrose gradient assay, 15% (4/27) of benign lesions and 56% (61/109) of malignant tumors were estrogen receptor-positive (ER-positive means 8S or 8S+4S levels more than 7 fmoles/mg cytosol protein). Progesterone receptors (PR) were tested on specimens from 28 patients and 39% (10/26) of the cancers were PR-positive. ER protein activity was not correlated with stage, histology, size of primary lesions, or extent of axillary or distant metastasis. Tumors with low ER levels are more likely to recur, and recurrent tumors after longer disease-free intervals are more likely to be ER-positive. Detailed analysis showed that ER levels did correlate with age and serum albumin levels. Concentrations of serum alpha1-globulin were decreased, while IgG and IgM were significantly increased among patients with positive ERs. Eighteen evaluable patients with advanced breast cancer had endocrine therapy, 13 had objective response. Twelve of these 13 had 8S receptor above 10 fmoles/mg, or 4S above 15 moles/mg, or 8S+4S above 25 fmoles/mg. The one exceptional patient had tumor with high PR but without detectable ER.
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PMID:Steroid receptors study in breast carcinoma. 74 84

Progesterone receptors in the autonomous rat mammary tumor MTW-9B are reduced 80 to 90 percent after ovariectomy, but are not reduced if ovariectomized animals are given estrogen. Tumor growth, however, is independent of estrogen status and insensitive to pharmacological doses of estradiol. This represents an unusual system characterized by a selective action of an inducing agent on the genome.
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PMID:Mammary cancer: selective action of the estrogen receptor complex. 76 Jan 95

Neonatal female mice of the BALB/cfC3H strain were given 5 daily injections of 17beta-estradiol and progesterone alone and in combination, beginning within 36 hr after birth. Half of the mice in each group were ovariectomized at 40 days of age, and all were killed at tumor age of at 12 months of age. Mice receiving progesteron (100 mug daily) alone showed ovary-dependent persistent vaginal cornification. When neonatal progesterone and estradiol were given concurrently, the occurrence of persistent vaginal cornification was significantly lower than in mice receiving neonatal estradiol treatment alone. Progesterone alone produced hyperplastic downgrowths and lesions of both vaginal and cervical epithelia, but to a lesser degree than occurred in mice treated neonatally with estrogen. When progesterone was given concurrently with 17beta-estradiol, the incidence of lesions was lower but their severity was greater. The low doses of 17beta-estradiol and progesterone each resulted in an earlier age of onset and a higher incidence of mammary tumors; this also occurred after both combined estrogen-progesterone treatments. In treated mice ovariectomized on Day 40, normal mammary development did not occur and mammary tumors failed to appear, regardless of neonatal treatment. The data indicate a clear effect of neonatal progesterone exposure on both the genital tract and the mammary apparatus of female mice.
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PMID:Long-term effects of neonatal treatment with progesterone, alone and in combination with estrogen, on the mammary gland and reproductive tract of female BALB/cfC3H mice. 83 Apr 22

Medroxyprogesterone acetate has been used to treat metastatic renal cell carcinoma largely because of its observed inhibitory effects on the growth of estrogen-induced tumors in male Syrian golden hamsters. The absence to date of any successful, established chemotherapeutic regimen in the management of metastatic renal cell carcinoma has led to the continued application of medroxyprogesterone acetate in the majority of patients with this disease because of the occasional regression witnessed (particularly in male patients) and the absence of untoward side effects. To examine the mechanism of action of medroxyprogesterone acetate renal cell carcinoma tumor cells from a patient who had responded to medroxyprogesterone acetate therapy were established in tissue culture. Cells were cultured in control medium, and in the presence of therapeutic and pharmacologic levels of medroxyprogesterone acetate. Tumor cell growth kinetics were determined by the incorporation of 3H thymidine. There was no growth inhibition effected by medroxyprogesterone acetate at therapeutic or pharmacologic levels. Therefore, the proposed salutary effect of medroxyprogesterone acetate in regression of metastatic renal cell carcinoma results from factors other than direct inhibition of renal cell carcinoma growth.
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PMID:Role of hormones in growth kinetics of renal cell carcinoma in vitro. 83 83

A study was made of the endometria of 16 patients with gonadal dysgenesis who had been give cyclic replacement treatment with conjugated estrogens for 2 to 10 years, and of 9 other patients who had received medroxyprogesterone in addition to the conjugated estrogens for 2 to 5 years. Seven of the former group showed varying degrees of endometrial hyperplasia, and in all of these cases the duration of estrogen therapy had exceeded 5 years. At the time of the study no cases had developed frank adenocarcinoma. Only 1 of the 9 patients who had been given medroxyprogesterone in addition to the conjugated estrogens demonstrated evidence of hyperplastic change. Progesterone may afford some protection against the development of endometrial hyperplastic activity, but its potential role in protecting against neoplasia remains to be determined. This study supports the view that estrogen replacement therapy in gonadal dysgenesis carries the risk of endometrial hyperplasia and neoplasia. Possible methods of decreasing this hazard are discussed.
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PMID:Endometrial response to estrogen and progesterone therapy in patients with gonadal dysgenesis. 87 52

A case report on an unusual hormone producing ovarian tumor in a 3 year old girl with sexual precocity is given. The serum values of Estradiol and Progesterone were similar to those of mature women during the luteal phase. The LH values were normal, the 17-Ketosteroids and 17-Hydroxycorticosteroids were near the upper limit of the normal range. At laparotomy a smooth, encapsulated tumor of the left ovary, 12 cm in diameter, was removed by unilateral salpingo-oophorectomy. Hormone analyses of the blood of the ovarian vein as well as of necrotic parts of the tumor showed values of 3450 and 2750 pg/ml Estradiol, and 70 000 and 75 000 pg/ml Progesterone respectively. Histiologically the tumor cells were growing in nests and broad columns, showing bizarre nuclei, abundant pathologic mitoses and patchy calcification. In places the tumor cells were forming follicle-like structures. Both the fat stain and the glycogen stain were positive. Histochemically the tumor showed a strong activity of 3beta-ol-Steroiddehydrogenase. Postoperatively the signs of sexual precocity disappeared soon. The patient is now without complaints for 3 years. The diagnosis of a juvenile granulosa cell tumor (Scully) was given. The endocrine relations between sexual steroids and gonadotropin before and after surgery are discussed.
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PMID:[An unusual hormone-active avarian tumor in a 3-year-old girl]. 101 97


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