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Query: UMLS:C0006142 (breast cancer)
 160,383 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Predictive tests assisting in selection of breast cancer patients for endocrine therapy have been reviewed. Information gained from histologic sections, such as degree of the tumor differentiation, degree of elastosis, Barr-body count and the DNA content, are valuable predictors of prognosis and response to endocrine therapy. The length of time between mastectomy and recurrence of metastasis is an important factor in predicting response to ablative endocrine surgery. The presence of various enzymes in the tumor tissue, blood groups, immunologic competence, altered metabolism of tryptophan, urinary excretion of steroids and in vitro hormonal responsiveness of the tumor tissue have not been widely used as predictors of tumor response to endocrine therapy. The determination of hormone receptors in primary or metastatic breast tumors is at present the most reliable test in selecting breast cancer patients for endocrine therapy. Future developments in hormone receptor assay may provide a means of tailoring endocrine therapy to the individual patient.
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PMID:[Selection of patients with breast cancer with regard to endocrine therapy]. 19 40

Women with early breast cancer were given a loading dose of L-tryptophan after mastectomy and a comparison made between their excretion of metabolites of the kynurenine pathway and the rate of recurrence of the disease.
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PMID:Tryptophan metabolism and recurrence rates of patients with breast cancer after mastectomy. 124 77

A case-control study was performed to evaluate hormonal status in 154 female patients with bladder cancer and 213 healthy women. Cancer patients were characterized by shorter reproductive period and miscarriage, absence of gestation, endometrial and breast cancer and ovarian cysts in the past history. Evaluation of tryptophan metabolism in 131 male and 111 female patients with bladder cancer showed the occurrence of a carcinogenic metabolite--3-oxyanthranilic acid--in the urine to be higher in women. Blood hormone levels were measured in 55 female patients and 49 healthy women by radioimmunoassay. Decreased levels of progesterone and estradiol as well as of hormones potentiating their production (folitropin and lutropin) were the most frequent hormonal disorders encountered.
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PMID:[Endogenous risk factors for bladder neoplasms in women]. 184 51

Melatonin is an indolamine synthesized from tryptophan in the pineal gland. It is regarded as "the epiphyseal hormone". Its antigonadotropic action has been demonstrated in animals, both in vitro and in vivo, together with its inhibitory effect on numerous endocrine functions and its anti-convulsive properties. Recently developed assay methods have made it possible to obtain clinical data, for the moment purely descriptive. Melatonin is present in several body fluids, such as urine, blood and cerebrospinal fluid. It is secreted in circadian cycles, with low concentrations during the day and high concentrations at night; sex has no influence on this pattern, but secretion is highest in the summer and winter and lowest in the spring and autumn. The part played by melatonin in the genesis of puberty is undetermined. Melatonin secretion appears to be mediated by the adrenergic system, since beta-blockers inhibit the nocturnal rise. However, contrary to what happens in animals, most beta-adrenergic stimulants do not increase melatonin concentrations. Abnormal concentrations or perturbations in the melatonin secretion rhythm have been demonstrated in such diseases as breast cancer, cirrhosis of the liver, Klinefelter's syndrome, Cushing's syndrome and haemochromatosis. Depressive syndromes are often associated with abnormal melatonin cycles. It has been suggested that melatonin could be used as a biological marker in cancer and psychiatric diseases, but its physiological function in man remains obscure.
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PMID:[Melatonin]. 293 8

The nutritional status of three groups of postmenopausal women (age 41-80 yrs) with advanced breast cancer was investigated with special reference to vitamin B6. The interference of hormonal treatment was studied with respect to the progestin megestrol acetate (Group MA, n = 14) and the antiestrogen tamoxifen (Group TAM, n = 15) compared with untreated patients (Group U, n = 11). Healthy postmenopausal women served as controls (Group C, n = 16). Nutritional status was judged from body mass index (BMI), vitamin and trace element status, hematology, and clinico-chemical parameters. Intake of nutrients was calculated from a food record. Hormonal status was studied by analysis of LH, FSH, and prolactin in plasma and of steroids and catecholamines and their metabolites in 24-hour urine. Compared with values for Group C, nutrient intake, hematology, clinico-chemical parameters, and 24-hour urinary excretion of catecholamines and their metabolites of patient groups (U, TAM, and MA) were not significantly different. The BMI of patients was significantly higher (by about 10%; 60% showed an overweight) than that of controls. With respect to fat-soluble vitamin status, significantly lower plasma levels of vitamin A (at least 40% lower, with deficient levels in more than 50% of the patients), D (40% lower), and E (20% lower) were found for Group U. However, water-soluble vitamin status of the four groups was fairly similar. A significantly higher excretion of xanthurenic acid in 24-hour urine, after an oral tryptophan load, was observed for Groups TAM and MA. This is most probably the result of hormonal treatment without affecting vitamin B6 status. Small, but significant, differences between groups were found for trace element status, especially with respect to lower plasma selenium of Group U (25% lower). LH, FSH, and prolactin in plasma and excretion of steroids in 24-hour urine showed levels that could be expected for controls and for untreated and hormonally treated patients. We concluded that the nutritional status of all patients is reasonably adequate. Hormonal treatment did not influence vitamin B6 status, although levels of vitamins A, D, and E and of selenium seem to be elevated.
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PMID:Investigations on the nutritional status of advanced breast cancer patients. The influence of long-term treatment with megestrol acetate or tamoxifen. 343 93

Plasma levels of total tryptophan were significantly lower in 51 patients with breast cancer than in 14 women with benign breast cancer following surgery and after 12 weeks. The urinary excretion of xanthurenic and 5-hydroxyindoleacetic acids were similar in patients with cancer and benign disease but the excretion of N'-methylnicotinamide (NMN) was significantly higher (P less than 0.001) in the cancer patients. It is suggested that the elevated urinary excretions of NMN is due to higher NAD activity reflecting elevated glycolysis through the Cori cycle.
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PMID:Tryptophan metabolism in patients with breast cancer. 403 62

It has been suggested that the well-documented relationship of dietary composition to the incidence of human breast cancer is mediated by the effects of dietary constituents on hormone levels. There is fairly good evidence for diet-hormone relationships in animals, but the evidence in humans is unconvincing. In this paper, we describe three of our findings relating nutrition to hormone levels: (a) that obesity causes retention of a tracer of estradiol in women but not in men, a finding we attribute to the presence of specific estrogen receptor in the adipose tissue of women but not men; (b) that obese men have elevated plasma estrone and estradiol levels but obese women do not, a finding we attribute to greater androstenedione-to-estrone conversion in the adipose tissue of men than in that of women; and (c) that cachectic girls with anorexia nervosa fail to have the normal nocturnal surge of prolactin secretion, a finding that we attribute to deficiency of tryptophan, which is an adequate stimulus for prolactin secretion. These findings give support to the concept that dietary factors affect hormone secretion and/or metabolism in humans.
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PMID:Influence of obesity and malnutrition on the metabolism of some cancer-related hormones. 726 Sep 51

In order to evaluate whether different solid tumors may specifically influence plasma free amino acid (PFAA) profile, PFAA were analysed in seventy-four patients with lung (41 patients) and breast cancer (33 patients) and 28 healthy subjects. In lung cancer patients a significant reduction of gluconeogenic amino acids, threonine, serine, glycine and a significant increase of free tryptophan and glutamic acid was found. In breast cancer patients a significant increase of ornithine, glutamic acid and free tryptophan was found. The comparison of PFAA profiles between lung and breast cancer suggests that different tumors have a different influence on the host's PFAA pattern.
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PMID:Plasma amino acid imbalance in patients with lung and breast cancer. 776 31

Previous studies on human breast cancer patients showed a decline in circulating melatonin levels corresponding to primary tumor growth and an increase when relapse occurred. The aim of the current investigation was to study in an experimental model possible mechanisms involved. Inbred female F344 Fischer rats were used for serial passages derived from a chemically induced mammary adenocarcinoma. Animals with slow-growing carcinosarcomas at passage 2 showed a significant elevation of nocturnal urinary melatonin (23. 00-07.00 h; +50%, p < 0.05) and a nominal increase in plasma melatonin (+41%; 02.00-03.00 h). By contrast, these parameters were significantly depressed in animals with fast-growing sarcomas (urinary melatonin: -22%, p < 0.025; plasma melatonin: -56%, p < 0. 01). At passage 2 nocturnal pineal N-acetylserotonin (02.00-03.00 h) was significantly enhanced (+62%, p < 0.05) probably due to an increased activity of serotonin-N-acetyltransferase (SNAT, +45%), the rate-limiting step of pineal melatonin biosynthesis converting serotonin to N-acetylserotonin. The activation of SNAT may be due to a stimulation of the sympathetic nervous system (urinary noradrenaline; NA: +243%, p < 0.005) when the cellular immune system responded towards tumor growth (urinary biopterin, +214%, p < 0.005). At passage 12 SNAT and N-acetylserotonin were unaffected but a depletion of plasma tryptophan (-34%, p < 0.0001), the precursor amino acid of melatonin, was found. The marginal decline in pineal serotonin (-18%, p < 0.05) disputes that the drastic depletion in circulating melatonin (-56%, p < 0.01) can be exclusively explained by a reduced availability of tryptophan. Therefore, the involvement of an additional mechanism has to be postulated, such as a degradation of melatonin via indoleamine 2,3-dioxygenase, an extrahepatic enzyme which has been detected in tumor tissue and is related to tryptophan 2,3-dioxygenase (TDO). TDO occurs only in the liver, is highly specific for L-tryptophan and is induced by glucocorticoids which would account for the observed depletion of plasma tryptophan resulting from a tumor-associated activation of the hypothalamo-pituitary-adrenal axis (urinary corticosterone +208%, p < 0.01). These findings present first explanations for the previously observed modulation of melatonin levels in cancer patients but also illustrate the high degree of complexity of mechanisms involved in the interactions between tumor growth and the immunoneuroendocrine system.
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PMID:Serial transplants of DMBA-induced mammary tumors in Fischer rats as a model system for human breast cancer. VI. The role of different forms of tumor-associated stress for the regulation of pineal melatonin secretion. 994 5

In general, the root of a seaweed is poorly developed as compared with its thallus and is called the rhizoid or holdfast. In Laminaria, belonging to Phaeophyceae, although the thallus is used for food, the rhizoid is considered an unuseful natural resource. We attempted to detect anti-breast cancer substances from that resource. As a result, a substance having a weak absorptivity to aluminium oxide and Sephadex G-25 was found. According to analysis of the FAB-MS spectra and 1H NMR spectra, the substance was identified as tryptophan, an amino acid. Finally, it was concluded by a chiral column-HPLC method that the tryptophan was the L-form.
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PMID:[Substance isolated from the kelp rhizoid identified as L-tryptophan shows high inhibition of breast cancer]. 1070 Aug 96


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