Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0006142 (breast cancer)
 160,383 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Epidemiological evidence links breast cancer, a typical endocrine-related tumor, with western lifestyle, in particular eating habits. Yet, it's necessary to distinguish premenopausal from postmenopausal breast cancer. Visceral obesity and body weight gain are considered responsible for the increased risk of postmenopausal breast cancer. In fact, the mammary gland is sensitive to the level of circulating estrogens, visceral obesity is usually associated with higher levels of free steroid hormones, and the adipose tissue performs important endocrine function (clearance and aromatisation of androgens, regulation of free testoterone/DHEAS molar ratio). Before menopause, ovarian polycystosis is often seen with android obesity, and breast cancer risk could arise; however, as visceral obesity is generally less frequent, genetic factors are more important than nutritional ones. Furthermore, variations have been recorded in the secretion of insulin and insulin-like growth factors, involved in the genesis of the breast cancer. High body weight and male fat distribution negatively influence prognosis of breast cancer, too; this association is linked with the presence of estrogen and progesterone receptors in tumoral cells. Links between diet quality and breast cancer risk are shown: increased use of saturated fats and animal proteins, and a consequently decreased use of vegetables, legumes and fruit, constituting the so-called Mediterranean diet, are considered responsible for the increased risk of breast cancer. Lower fat and alcohol ingestion, the use of dietary fibre and a higher use of complex carbohydrates could reduce breast cancer risk. Finally, starting from the results of our previous animal researches, we suggest using a tryptophan devoid diet for a few days for premenopausal women with male obesity and alterations to the menstrual cycle.
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PMID:Breast cancer and obesity. 1144 84

We have identified and characterized a gene (60% on protein level) and a pseudogene (93% on DNA level) that show high similarity to the Wolf-Hirschhorn syndrome candidate gene-1 (WHSC1). These genes, WHSC1L1 and WHSC1L2P, map to human chromosomes 8p11.2 and 17q21, respectively. WHSC1L1 is ubiquitously expressed and, like WHSC1, generates two major transcripts, a short (s-type) and a long (l-type). The WHSC1L1 l-type transcript encodes a 1437-amino-acid protein containing 2 PWWP (proline-trypto-phan-proline-tryptophan) domains, 5 PHD (plant-home-domain)-type zinc finger motifs, a SAC (SET-associated Cys-rich) domain, and a SET (Suppressor of Variegation, Enhancer of Zeste and Trithorax) domain. The s-type transcript encodes a protein of 645 amino acids containing a PWWP domain only. WHSC1L2P is an unexpressed, intronless pseudogene of a WHSC1L1 s-type transcript. The 8p11.2 region around WHSC1L1 contains a set of genes including TACC1, FGFR1, LETM2, and WHSC1L1, which seems to be derived from a recent duplication involving 4p16.3 where a similar set of genes is located. Rearrangements of 8p are frequently found in human cancer, including breast cancer. These characteristics indicate that WHSC1L1 might have a role in embryonic development and, when disregulated, in cancer development.
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PMID:WHSC1L1, on human chromosome 8p11.2, closely resembles WHSC1 and maps to a duplicated region shared with 4p16.3. 1154 11

Cyclin E, one of the activators of the cyclin-dependent kinase Cdk2, is expressed near the G1-S phase transition and is thought to be critical for the initiation of DNA replication and other S-phase functions. Accumulation of cyclin E at the G1-S boundary is achieved by periodic transcription coupled with regulated proteolysis linked to autophosphorylation of cyclin E. The proper timing and amplitude of cyclin E expression seem to be important, because elevated levels of cyclin E have been associated with a variety of malignancies and constitutive expression of cyclin E leads to genomic instability. Here we show that turnover of phosphorylated cyclin E depends on an SCF-type protein-ubiquitin ligase that contains the human homologue of yeast Cdc4, which is an F-box protein containing repeated sequences of WD40 (a unit containing about 40 residues with tryptophan (W) and aspartic acid (D) at defined positions). The gene encoding hCdc4 was found to be mutated in a cell line derived from breast cancer that expressed extremely high levels of cyclin E.
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PMID:Human F-box protein hCdc4 targets cyclin E for proteolysis and is mutated in a breast cancer cell line. 1156 17

Nonmalignant (n = 36) and malignant (n = 20) tissue samples were obtained from breast cancer and breast reduction surgeries. These tissues were characterized using multiple excitation wavelength fluorescence spectroscopy and diffuse reflectance spectroscopy in the ultraviolet-visible wavelength range, immediately after excision. Spectra were then analyzed using principal component analysis (PCA) as a data reduction technique. PCA was performed on each fluorescence spectrum, as well as on the diffuse reflectance spectrum individually, to establish a set of principal components for each spectrum. A Wilcoxon rank-sum test was used to determine which principal components show statistically significant differences between malignant and nonmalignant tissues. Finally, a support vector machine (SVM) algorithm was utilized to classify the samples based on the diagnostically useful principal components. Cross-validation of this nonparametric algorithm was carried out to determine its classification accuracy in an unbiased manner. Multiexcitation fluorescence spectroscopy was successful in discriminating malignant and nonmalignant tissues, with a sensitivity and specificity of 70% and 92%, respectively. The sensitivity (30%) and specificity (78%) of diffuse reflectance spectroscopy alone was significantly lower. Combining fluorescence and diffuse reflectance spectra did not improve the classification accuracy of an algorithm based on fluorescence spectra alone. The fluorescence excitation-emission wavelengths identified as being diagnostic from the PCA-SVM algorithm suggest that the important fluorophores for breast cancer diagnosis are most likely tryptophan, NAD(P)H and flavoproteins.
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PMID:Comparison of multiexcitation fluorescence and diffuse reflectance spectroscopy for the diagnosis of breast cancer (March 2003). 1461 93

The activity and expression of indoleamine 2,3-dioxygenase together with L-tryptophan transport has been examined in cultured human breast cancer cells. MDA-MB-231 but not MCF-7 cells expressed mRNA for indoleamine 2,3-dioxygenase. Kynurenine production by MDA-MB-231 cells, which was taken as a measure of enzyme activity, was markedly stimulated by interferon-gamma (1000 units/ml). Accordingly, L-tryptophan utilization by MDA-MB-231 cells was enhanced by interferon-gamma. 1-Methyl-DL-tryptophan (1 mM) inhibited interferon-gamma induced kynurenine production by MBA-MB-231 cells. Kynurenine production by MCF-7 cells remained at basal levels when cultured in the presence of interferon-gamma. L-Tryptophan transport into MDA-MB-231 cells was via a Na(+)-independent, BCH-sensitive pathway. It appears that system L (LAT1/CD98) may be the only pathway for l-tryptophan transport into these cells. 1-Methyl-D,L-tryptophan trans-stimulated l-tryptophan efflux from MDA-MB-231 cells and thus appears to be a transported substrate of system L. The results suggest that system L plays an important role in providing indoleamine-2,3-dioxygenase with its main substrate, L-tryptophan, and suggest a mechanism by which estrogen receptor-negative breast cancer cells may evade the attention of the immune system.
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PMID:Indoleamine 2,3-dioxygenase activity and L-tryptophan transport in human breast cancer cells. 1496 80

The synthesis and biological evaluation of novel L-tryptophan pyrrole, imidazole polyamide conjugates (16-21), L-tryptophan-glycosylated pyrrole polyamide conjugates (28-30), L-tryptophan dimers (37-42) with straight carbon links of varying length, and L-tryptophan dimers (68-73) linked with pyrrole and imidazole polyamide from both sides by a flexible methylene chain of variable length are described. The compounds were prepared with varying numbers of pyrrole- and/or imidazole-containing polyamides and glycosylated pyrrole polyamides to determine the structural requirements for optimal in vitro antitumor activity. The compounds listed in Table 1 have been evaluated in a three cell line, one dose primary anticancer assay. The compounds listed in Table 2 have been evaluated against nine panels of 60 human cancer cell lines including leukemia, non-small cell lung cancer, colon cancer, CNS cancer, melanoma, ovarian cancer, renal cancer, prostate cancer, and breast cancer. It is observed from the initial cytotoxic data (Table 1) that compounds 16-19, 28-30, 68-69, and 71-73 have varying cytotoxic potencies against the three cancer cell lines. It is also observed, from the biological data from Table 2 for compounds 20-21, 37-42, and 70 against the 60 different tumor cells, that the L-tryptophan dimers 37-42 linked by a different number of carbon chains are more active than the L-tryptophan dimers linked by pyrrole or imidazole polyamides. The cytotoxic potency in tryptophan dimers, linked by a different number of carbon atoms increased the number of carbons between the two L-tryptophan rings.
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PMID:Synthesis and in vitro cytotoxicity studies of novel L-tryptophan-polyamide conjugates and L-tryptophan dimers linked with aliphatic chains and polyamides. 1497 56

Tumor growth is associated with a number of metabolic abnormalities. Glucose metabolism is deranged as frequently revealed by an impaired oral glucose tolerance test. Lipoprotein lipase activity is depressed, resulting in hypertrigliceridemia after an exogenous lipid load. Also protein metabolism is deranged in cancer patients, as revealed by changes of plasma amino acid profile. Our previous studies on plasma amino acids have shown that increased plasma free tryptophan levels are a frequent finding in cancer patients. To sustain a possible role for free tryptophan as a marker of neoplastic disease, we measured its plasma concentrations in 241 patients with cancer. Plasma free tryptophan concentrations were found to be significantly elevated with respect to healthy controls in patients with breast, lung, colon, stomach, and cancer from various origin. The sensitivity of this marker in predicting the presence of the tumor was highest for stomach and lung cancer patients. High plasma free tryptophan concentrations seem to be directly related to the presence of the tumor, since in breast cancer patients they returned to within normal range after eradicative surgery.
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PMID:Tumor-induced changes in host metabolism: a possible role for free tryptophan as a marker of neoplastic disease. 1520 51

Hormone replacement therapy (HRT) is contraindicated in women with a history of breast cancer or a high risk of breast cancer development. Recent results from large clinical trials, such as the Women's Health Initiative, have demonstrated increased risks of thromboembolic events and a moderate increased risk of breast cancer in women using conjugated estrogens and progestogens. There is a need for viable non-hormonal alternative treatments to HRT, such as nutritional and botanical therapies, in this population of women, who tend to experience more significant vasomotor symptoms. Safe and effective therapies that do not stimulate breast cell proliferation could prove extremely useful for the management of such symptoms for women in both low- and high-risk breast cancer populations. As a non-hormonal treatment, anti-depressants, such as selective serotonin reuptake inhibitors (SSRIs), have been shown to improve hot flash symptoms in women. The proposed mechanism is related to an increase in serotonin allowing for an increase in the set point of the brain's thermoregulator. In small clinical studies, the administration of tryptophan and 5-hydroxytryptophan (5HTP), the precursors of serotonin, have been shown to reduce depressive symptoms, possibly by enhancing the synthesis of serotonin. Thus, increased serotonin levels may have the ability to decrease hot flashes in a mechanism similar to that of SSRIs without the risks of breast cell stimulation. This would be particularly desirable for menopausal women with breast cancer or with risks of breast cancer. This article discusses the background information on hot flashes, SSRIs, tryptophan, and 5HTP, and possible clinical application of 5HTP for menopausal women with breast cancer risk.
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PMID:The potential of 5-hydryoxytryptophan for hot flash reduction: a hypothesis. 1616 76

Heme oxygenase-1 (HO-1) is the rate limiting enzyme of heme catabolism whereas indoleamine 2,3 dioxygenase (IDO) catabolizes tryptophan through the kynurenine pathway. We analyzed the expression and biological effects of these enzymes in rat and human breast cancer cell lines. We show that rat (NMU and 13762) but not human cells (MCF-7 and T47D) express HO-1. When overexpressed, we found this enzyme to have anti-proliferative and proapoptotic effects by antioxidant mechanisms in these four cell lines. We show that IDO is expressed by rat and human breast cancer cells. IDO inhibition with 1-MT and siRNA leads to diminished proliferation in rat cells. In contrast, HO-1 negative human cell lines increase proliferation upon IDO inhibition. Since we also demonstrate that IDO inhibits the anti-proliferative HO-1, we propose that IDO has opposite effects on proliferation depending on the coexpression or not of HO-1. We also describe that HO-1 inhibits IDO at the post-translational level through heme starvation. In vivo, we show that rat normal breast expresses HO-1 and IDO. In contrast, N-nitrosomethylurea-induced breast adenocarcinomas only express IDO. In conclusion, we show that HO-1/IDO cross-regulation modulates apoptosis and proliferation in rat and human breast cancer cells.
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PMID:Heme oxygenase-1 inhibits rat and human breast cancer cell proliferation: mutual cross inhibition with indoleamine 2,3-dioxygenase. 1631 39

A significant number of drugs and toxins have been associated with eosinophilic pneumonia. Antibiotics and NSAID, are the most commonly reported drugs. Toxins suspected to cause eosinophilic pneumonia include cigarette smoke and illicit drugs. Drug- or toxin-induced eosinophilic pneumonia is indistinguishable from idiopathic acute or chronic eosinophilic pneumonia by clinical, radiographic, and histopathologic criteria. The diagnosis is supported by a temporal relationship to a drug or toxin. The condition usually resolves with removal from the agent and recurs with rechallenge. Treatment involves discontinuation of the offending drug or toxin and treatment with corticosteroids in severe respiratory failure. There are also mass outbreaks of eosinophilic pneumonia reported, such as the toxic-oil syndrome in 1981 and the eosinophilia-myalgia syndrome related to the ingestion of L-tryptophan in 1989. A recent report has described an outbreak of acute eosinophilic pneumonia found in soldiers in Iraq. Radiation therapy has also been associated with the development of eosinophilic pneumonia in patients receiving this treatment for breast cancer.
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PMID:Drug-, toxin-, and radiation therapy-induced eosinophilic pneumonia. 1661 70


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