Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C1140680 (ovarian cancer)
 28,141 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Ovarian cancer originates mainly from surface epithelial cells, which are potential targets of estrogen action. Using immunohistochemistry and RT-PCR analysis, aromatase (estrogen synthetase) can be detected in human ovarian surface epithelial tumors. In this study, we functionally characterized the aromatase expressed in a primary cell culture, normal human ovarian surface epithelial (HOSE) 17. The apparent K(m) and V(max) values were determined to be 5.8 +/- 0.5 nM, and 0.3 +/- 0.0 pmol/mg.h, respectively. The aromatase activity in HOSE 17 cells can be induced effectively by phorbol esters and forskolin, suggesting that estrogen biosynthesis in HOSE 17 cells is mainly regulated through protein kinase C- and protein kinase A-mediated mechanisms. Exon I-specific RT-PCR revealed that phorbol esters predominantly up-regulated promoter II. Whereas forskolin treatment increased exon I.3A-containing messenger RNA, the aromatase activity remained low in the cells treated with this agent. In vitro transcription/translation analysis using plasmids containing T7 promoter and the human snail gene (SnaH) as a reporter capped with different untranslated exon Is revealed that exon PII-containing transcripts were translated more effectively than exon I. 3-containing transcripts. These findings explain why aromatase activity is higher in cells with the PII-containing transcripts than is cells with the I.3-containing transcripts. Our results indicate that aromatase is functionally expressed in human ovarian surface epithelial cells and its expression is regulated at both the transcriptional and translational levels.
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PMID:Regulation of aromatase expression in human ovarian surface epithelial cells. 1113 58

Based on short reviews of lung, gastric, colorectal, prostate, breast and ovarian cancer, there remain significant differences between Japan and the West in the therapeutic regimen for most cancers. Some of the differences are due to differences in stage of disease at diagnosis or historical factors affecting availability of products. In both Japan and the West, there are initiatives to prepare treatment guidelines based on published data. For Japan this initiative is limited by the lack of Japanese clinical trial data or even safety data. When guidelines are prepared from international data, many of the products have limited indications in Japan and therefore not reimbursed. Availability of the most appropriate therapies to Japanese patients will depend on a facilitation of clinical trials in both primary and additional indications. However, the experience in other countries is that, even where data and registration approval are available, guidelines are hard to agree and are not uniformly accepted by prescribers. The ICH E5 guideline on the use of bridging studies to interpolate Western data to Japanese regulatory dossiers provides an opportunity to accelerate availability of new medicines to Japanese prescribers and patients. The use of bridging studies has so far been limited for anti-cancer therapies. Where relevant pharmacodynamic endpoints can be measured, (e.g. aromatase inhibition) there can increase confidence in bridging. The newer types of agent which act to stabilise disease rather than tumour shrinkage present a special problem. In some cases surrogate markers can be valuable but in each case they need to be validated. As globalization continues, an alternative approach is to include a significant cohort of Japanese patients in Japanese patients but this depends on sufficient similarity in the patient population and background therapy. The most significant limitation to either large outcome studies in Japan or for Japanese centers to join international trials has been the environment for conduct of clinical trials. There have been some recent improvements and further progress is expected so that Japanese doctors can play a full role in the evaluation of new therapies.
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PMID:[Globalization of anti-cancer therapies]. 1186 25

Tamoxifen is a selective estrogen receptor modulator (SERM) with pro- and anti-estrogenic properties. Currently it is the most widely used agent for first line treatment against hormone sensitive metastatic breast cancer and the only approved hormonal agent for adjuvant treatment of organ confined breast cancer. Furthermore, its uses have been extended for the treatment of intraductal breast carcinoma patients. In such settings the most worrisome side effect of tamoxifen is its ability to increase the rates of uterine cancers. It has been claimed that most of these cancers are found at an early stage because of vaginal bleeding. Moreover, it has been shown that for most women transvaginal ultrasound is an ineffective screening method for the early detection of uterine carcinomas. It is important, however, to notice that long term tamoxifen treatment can cause metastatic uterine cancer--not only carcinomas but also sarcomas (mainly malignant mixed mesodermal tumors. It should be noted that, at least for the special population of BRCA mutation carriers, transvaginal ultrasound can increase our ability for the earlier discovery of ovarian cancer. Thus, we believe that there is still a place for the use of transvaginal ultrasound in special populations. This is specifically for long term tamoxifen users (more than the usually recommended five years), women with a higher chance of having uterine carcinomas (namely very high body weight, strong family history) and women with a high index of suspicion as carriers of a BRCA mutation. Until new second generation SERMs and aromatase inhibitors are shown to possess better anti-cancer abilities than tamoxifen, this drug will remain in wide use, however, we must not overlook its possible rare side effects.
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PMID:[Tamoxifen and breast cancer]. 1222 37

The analytical representation and simulation of complex molecular pathways can contribute to understanding and evaluating physiological as well as pathological processes. We are interested in modeling the processes of menopause to stratify women in terms of the genotypic and environmental components and their implications for development of individualized risk of postmenopausal disorders, e.g., breast and ovarian cancer, cardiovascular disease, and osteoporosis. We have initiated this study using the UltraSAN package to analyze the pathway associated with estrogen production. This model incorporates detailed information about the hormone factors affecting estrogen production, and the simulations carried out are based on published experimental data corresponding to hormone levels during the course of the normal female reproductive cycle. The agreement between the experimental data and the simulation is typically less than 2 ng/ml or 2 pg/ml respectively for progesterone and estradiol output. This approach further permits inclusion of information about an SNP observed in the gene coding for the enzyme aromatase as a model to study the impact of reduced enzymatic activity on hormone levels.
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PMID:Modeling and simulation of pathways in menopause. 1222 98

Between 1990 and 2001, altogether 28 new anticancer drugs were approved for use in Israel. The new agents include cytotoxic drugs, biologic compounds, and hormone therapies. Among the cytotoxic agents introduced, the taxanes, vinorelbine, gemcitabine, irinotecan, topotecan and temozolomide, represent important new drugs active in a range of solid malignancies including lung, breast, ovarian, bladder, pancreatic, and colon cancer as well as brain tumors. Epirubicin, idarubicin, and liposomal doxorubicin offer less toxic and in some instances more effective alternatives to older anthracylines for leukemia, breast cancer, ovarian cancer and other diseases. New oral agents are offering a chance for disease palliation without the need for burdensome intravenous access. Rituximab and trastuzumab have introduced monoclonal antibody therapy to the clinic, substantially improving the treatment of patients with lymphoma and breast cancer, respectively. The first tyrosine kinase inhibitor, a molecularly targeted therapy, imatinib, was approved for use in chronic myeloid leukemia and has also shown remarkable activity in gastrointestinal stromal tumors. A variety of aromatase inhibitors have provided less toxic and more effective hormone therapy for the treatment of breast cancer. The challenge for clinicians is to optimize the use of the new available agents for their patients' benefit, and the challenge for health policy-makers in Israel is to integrate the new anticancer pharmaceuticals into the basic health benefits package mandated for all citizens.
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PMID:New drugs for the treatment of cancer, 1990-2001. 1251 6

All androgens and estrogens in post-menopausal women are synthesized locally in peripheral target tissues by tissue-specific steroidogenic enzymes according to the intracrine process. The importance of the intracrine or peripheral formation of sex steroids is illustrated by the success of aromatase inhibitors and antiestrogens in the prevention and treatment of breast cancer in post-menopausal women. On the other hand, a large series of problems are associated with the deficiency of sex steroids accompanying menopause and the decreased secretion of DHEA, osteoporosis being the best defined example. In this context, an important observation is that women at menopause are not only deprived from ovarian estrogens but are also lacking androgens due to the marked decrease of DHEA. In order to achieve a more physiological and tissue-specific hormone replacement therapy, DHEA, in combination with a SERM (selective estrogen receptor modulator) having pure antiestrogenic activity in the mammary gland and uterus could possibly meet the most important needs of women at menopause, namely control of hot flushes and, most importantly, prevent breast cancer, uterine cancer, ovarian cancer and osteoporosis with a potential improvement of cognitive functions and memory and prevention of Alzheimer's disease.
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PMID:Extragonadal synthesis of sex steroids: intracrinology. 1277 42

Biomira is developing a therapeutic cancer vaccine [THERATOPE] for treatment of breast and other cancers. This profile has been selected from R&D Insight, a pharmaceutical intelligence database produced by Adis International Ltd. THERATOPE consists of the mucin antigen, sialyl-Tn (STn), a carbohydrate located on the surface of breast, colorectal and ovarian cancer cells, conjugated to keyhole limpet haemocyanin (KLH). Merck KGaA has acquired a worldwide licence to THERATOPE for treatment of breast cancer. Under the terms of the licence, Biomira and Merck KGaA, via its US affiliate, EMD Pharmaceuticals, will jointly market the vaccine in the US. Merck KGaA holds exclusive marketing rights for the rest of the world, except in Canada (where Biomira retains rights), Israel and the Palestine Autonomy Area. Merck KGaA is now collaborating on phase III development for breast cancer. Biomira stands to receive $US150 million in licence, milestone payments and equity investments. The development costs will be shared between the two companies in North America but Merck KGaA will be solely responsible for these costs in countries outside the US. Previously, Chiron Corporation had purchased a licence to THERATOPE in 1997; however, Chiron terminated this agreement in June 2000. Under the terms of the termination, Biomira paid Chiron $US2.25 million to compensate the company for its investment in the development of THERATOPE. In addition, Biomira will make another payment of $US3.25 million to Chiron upon FDA approval of the vaccine. No further payments or royalties will be made. In the third quarter of 2002, an independent review of interim data from the trial was conducted. This was the fifth scheduled review of the data by the Independent Data Safety Monitoring Board (DSMB), all of which produced a positive response. Following the completion of the review, the DSMB stated that the trial should continue and that it had no safety concerns regarding this trial. Although the data, to which Biomira and Merck KgaA are blinded, did not meet the predetermined statistical significance for either endpoint at the time of the review, both companies have chosen to continue with the trial. Biomira has since announced that the p-value for the interim survival analysis was set at 0.01, while it is set at 0.03 for final survival analysis. The tighter criteria was set for the interim analysis to potentially give the companies the opportunity of applying for marketing approval earlier than expected. Final analysis of the trial will take place in mid-2003. If these analyses indicate therapeutic efficacy, Biomira will meet the FDA and Canadian regulatory officials to obtain marketing approval for the vaccine for breast cancer under the accelerated review guidelines. Assuming a best-case scenario, the vaccine could be filed for approval in 2004. The phase III trial was initiated following positive preliminary results achieved in a bridging study in patients with metastatic breast cancer in the US and UK. Biomira announced final results of the bridging study in May 1999. The results confirmed that antibody titres against the STn antigen were significantly higher in patients treated with the improved formulation of THERATOPE, compared with the corresponding titres of patients in the phase II trials of the old formulation of THERATOPE. In September 2002, the first patient was enrolled in a phase II THERATOPE trial, which is enrolling patients with metastatic breast cancer who are taking either an aromatase inhibitor or fulvestrant. Approximately 95 patients will be enrolled in the trial at up to 12 US sites. The study is primarily designed to evaluate THERATOPE's ability to induce an immune response in these patients. However, the safety and tolerability of the aromatase inhibitor plus THERATOPE, and the fulvestrant plus THERATOPE combinations will also be evaluated. The trial has not been designed to evaluate the efficacy of the two combinations. The US FDA has granted fast-track status tranted fast-track status to THERATOPE for development as an adjunct to first-line combination chemotherapy in responding patients with metastatic breast cancer. A phase II trial in patients with metastatic colorectal cancer has been completed in the US; positive preliminary results from this trial were released in May 2001. On 24 November 1999, Biomira announced that it had licensed two patents covering methods of preventing growth of cancer cells expressing a mucin-type glycoprotein. The patents have been issued in the US and are pending in Japan and Canada. When issued in Japan, the patents will provide additional protection for THERATOPE in that country. The patents were licensed from Dr Sen-itiroh Hakomori of the Biomembrane Institute in Seattle, with whom Biomira has also entered into a research collaboration. Biomira announced in April 2003 that following examination of its re-issue application by the US Patent and Trademark Office, its patent 5798090 was re-issued (RE 38046) with additional claims. These additional claims represent broader patent coverage. The additional coverage will last until 2015. Earlier, in February 2000, Biomira announced an expansion of equity line for up to $US100 million; a 3-fold rise that was done without any additional shares of Biomira stock being issued. In June 2002, Biomira stated that it believes the market size for THERATOPE in the US, Europe and Japan to be approximately 184000 patients for the indication of metastatic breast cancer, of which the US would be 100000, Europe 75000 and Japan 9000. For the indication of colorectal cancer, the total market population for THERATOPE is expected to be 183000 patients, of which the US has been estimated at 100000, Europe 75000 and Japan 9000.
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PMID:Cancer vaccine THERATOPE- Biomira. 1284 88

Gonadotropins play a crucial role in ovarian homeostasis and fertilization. However, hypergonadotropin stimulation has been thought to increase the risk for ovarian cancer. Moreover, some correlation between high levels of gonadotropins in the circulation and Alzheimer's disease has been implicated, with no clear evidence on the molecular mechanism involved. Using DNA microarray technology and RNA from gonadotropin-stimulated human granulosa cells, which comprise the main bulk of the ovarian follicular somatic cells, we discovered that stimulation of cells with saturating doses of gonadotropins gives rise to the expression of genes coding for presenilin 1 and 2, along with the up-regulation of genes involved in steroidogenesis such as StAR, cytochrome P450scc enzyme system and aromatase. Moreover, gonadotropin stimulation in these cells dramatically elevates activity of genes coding for epiregulin and amphiregulin, which can bind and activate the EGF receptor and ERB4. These gene products may elevate the risk for ovarian, breast, endometrial and other non-gynecological cancers. Gene transcripts for oncogenes and tumor markers such as pleiomorphic adenoma gene-like 1 (Plagl1) tumor antigen (L6) and claudin 3 were markedly elevated following LH and FSH stimulation. In parallel, downregulation in ovarian cancer 1 (DOC1) and suppression of tumorigenicity (ST5) genes was observed, suggesting a potential increase for cancer development. In contrast, increase in tumor rejection antigen (gp96) 1 and decrease in connective tissue growth factor (CTGF), transforming growth factor-beta 1 induced transcript 1 (TGFB1Il), pim-1 oncogene (PIM1), v-maf musculoaponeurotic fibrosarcoma oncogene homologue (MAF) and CD24 antigen may be associated with a decreased risk for specific cancers. In conclusion, gonadotropin stimulation may modulate specific sets of gene transcripts that may either elevate or reduce the risk for specific diseases.
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PMID:Gonadotropin-induced gene regulation in human granulosa cells obtained from IVF patients: modulation of genes coding for growth factors and their receptors and genes involved in cancer and other diseases. 1506 57

Exemestane, a non-steroidal aromatase inhibitor that shuts down estrogen synthesis, and paclitaxel, an antineoplastic drug, inhibiting microtubule formation and interfering with the cells potential to proliferate, are well established treatments for metastatic breast cancer. Given that exemestane is a treatment for hormone-sensitive tumors in postmenopausal women with more favorable prognosis, while paclitaxel is normally used for women suffering from hormone-insensitive breast cancers with less favorable prognoses, there is currently no experience with the combination of the two drugs. In order to find out to what extent exemestane and paclitaxel add to each other's effects when given concomitantly, the effect of the two drugs alone and in combination on the growth of various gynecological tumor cell lines was assessed. Tumor cell growth was measured according to the cell titer cell proliferation technique, also referred to as the MTS assay, by measurement of relative cell numbers. In gynecological cancer cells expressing aromatase, the effect of a treatment with paclitaxel (10 nM) on cell growth was enhanced by co-treatment with exemestane. This additive effect was independent of ERalpha expression, but dependent on the presence of androstenedione. It was observed in HEC-1A and Ishikawa endometrial adenocarcinoma cells as well as in SK-OV-3 ovarian cancer and in MDA-MB-231 breast cancer cells. Our findings suggest that a combination of paclitaxel with exemestane might be beneficial for the treatment of aromatase-positive gynecological cancer, because it may allow us to reduce the paclitaxel dosage and therefore the toxicity of the treatment.
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PMID:Effects of a combination of exemestane and paclitaxel on human tumor cells in vitro. 1509 Jul 44

Familial breast cancer, whether associated or not with particular other breast cancer features (male, early onset, bilateral breast cancer), determines a wide and variable risk of developing breast cancer in the 'unpatients' (unaffected individuals) of these families, particularly in those harboring a genetic predisposition. The antiestrogen tamoxifen has been proposed in different trials to prevent breast cancer in women at risk. The NSABP-P1 study demonstrated that tamoxifen drastically reduced (by approximately 50%) the incidence of breast cancer in women at risk selected according to the Gail score. The preventive effect was particularly consistent in postmenopausal women and in those showing familial breast cancer (three or more affected patients). BRCA1/BRCA2 (BRCA1/2) gene analysis in women accrued in the NSABP-P1 trial who developed breast cancer showed that tamoxifen chemoprevention reduced breast cancer incidence in BRCA2 carriers. Different chemoprevention trials are ongoing to compare different selective estrogen receptor modulators and aromatase inhibitors with tamoxifen. The Italian Consortium of Hereditary Breast Ovarian Cancer recently developed the Aromasin Prevention Study, a multicenter, double-blind, randomized, placebo-controlled phase III study evaluating the effect of the aromatase inhibitor exemestane for chemoprevention in postmenopausal women carriers of BRCA1/2 genetic predisposition. Women who are postmenopausal unaffected carriers of BRCA1/2 mutations will be selected by participating institutions and randomly assigned to receive either oral exemestane or oral placebo every day for 3 years in order to reduce the incidence of breast cancer. Genetic counseling and the detection of predisposing BRCA1/2 mutations are mandatory before accrual into the study. Signed informed consents for the performing of BRCA1 and BRCA2 genetic analysis and for enrollment into the study are required. Eligible women will be followed thereafter in order to evaluate the efficacy of exemestane in reducing the incidental rate of breast cancer in unaffected postmenopausal carriers of BRCA1/2 mutations.
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PMID:Reducing breast cancer incidence in familial breast cancer: overlooking the present panorama. 1528 Jan 80


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