File Download

There are no files associated with this item.

  Links for fulltext
     (May Require Subscription)
Supplementary

Conference Paper: Inhibition of hormone-/growth factor-induced rise in cytosolic free calcium ([Ca2+]i) in human prostate cancer and choriocarcinoma cells by melatonin.

TitleInhibition of hormone-/growth factor-induced rise in cytosolic free calcium ([Ca2+]i) in human prostate cancer and choriocarcinoma cells by melatonin.
Authors
Issue Date2000
PublisherS Karger AG. The Journal's web site is located at http://www.karger.com/NSG
Citation
The 1999 International Symposium on Receptor and Non-Receptor Mediated Actions of Melatonin, Hong Kong, China, 6-8 November 1999. In Biological Signals and Receptors, 2000, v. 9 n. 1, p. 68-69 How to Cite?
AbstractMelatonin, a pineal gland neurohormone, has been shown to inhibit the proliferation of specific human cancer cells, some of which are derived from reproductive tissues such as the prostate and placenta. In many of these in vitro studies, the signal transduction mechanisms of the anti-proliferative action of melatonin are largely undefined. Given that calcium ion is an important second messenger which plays a pivotal role in the modulation of basic cellular processes such as proliferation, differentiation and apoptosis, the effects of melatonin on cytosolic calcium ([Ca2+]i) levels in human prostate LNCaP and PC-3 cells as well as choriocarcinoma JEG-3 cells were investigated. In addition, the effects of melatonin on changes in [Ca2+]i in LNCaP, PC-3 and JEG-3 cells induced, respectively, by sex steroids, gastrin-releasing peptide (GRP) and insulin-like growth factor I (IGF-I) were also studied. Although melatonin was found to exert no effect on basal [Ca2+]i in LNCaP cells, it reduced, dose-dependently (5 nM to 50 µM), the Ca2+ influx into LNCaP cells induced by 1 µM 17ß-estradiol (E2) or 0.1 µM 5•-dihydrotestosterone (DHT). Interestingly, estrogen and androgen antagonists (tamoxifen and cyproterone acetate) failed to block the Ca2+ influx into LNCaP cells induced by E2 and DHT. Similar to the results obtained in LNCaP cells, melatonin did not affect the basal [Ca2+]i in PC-3 and JEG-3 cells. While the rise in [Ca2+]i induced by 1 nM GRP in PC-3 cells was abrogated by 5 x 10–10M melatonin, IGF-I (10–8M)-induced increase in [Ca2+]i in JEG-3 cells was inhibited by 5 x 10–7 M melatonin. Our data suggest that melatonin may interact with sex steroids, GRP and IGF-I, through changes in intracellular calcium, in the modulation of the proliferation of androgen-sensitive LNCaP prostate cancer cells, androgen-insensitive PC-3 prostate cancer cells and choriocarcinoma JEG-3 cells respectively. The work described in this abstract was partially supported by a research grant from the Research Grants Council of the Hong Kong Special Administrative Region, China (Project No. HKU 7069/ 99M).
Descriptionpp. 53-75 of this journal issue entitled: Receptor and Non-Receptor Mediated Actions of Melatonin - International Symposium, Hong Kong, China, November 6-8, 1999
Persistent Identifierhttp://hdl.handle.net/10722/105250
ISSN
2003 Impact Factor: 3.5

 

DC FieldValueLanguage
dc.contributor.authorSiu, SWFen_HK
dc.contributor.authorFong, SWen_HK
dc.contributor.authorXi, SCen_HK
dc.contributor.authorWong, JTYen_HK
dc.contributor.authorShiu, SYWen_HK
dc.date.accessioned2010-09-25T22:26:18Z-
dc.date.available2010-09-25T22:26:18Z-
dc.date.issued2000en_HK
dc.identifier.citationThe 1999 International Symposium on Receptor and Non-Receptor Mediated Actions of Melatonin, Hong Kong, China, 6-8 November 1999. In Biological Signals and Receptors, 2000, v. 9 n. 1, p. 68-69en_HK
dc.identifier.issn1422-4933en_HK
dc.identifier.urihttp://hdl.handle.net/10722/105250-
dc.descriptionpp. 53-75 of this journal issue entitled: Receptor and Non-Receptor Mediated Actions of Melatonin - International Symposium, Hong Kong, China, November 6-8, 1999-
dc.description.abstractMelatonin, a pineal gland neurohormone, has been shown to inhibit the proliferation of specific human cancer cells, some of which are derived from reproductive tissues such as the prostate and placenta. In many of these in vitro studies, the signal transduction mechanisms of the anti-proliferative action of melatonin are largely undefined. Given that calcium ion is an important second messenger which plays a pivotal role in the modulation of basic cellular processes such as proliferation, differentiation and apoptosis, the effects of melatonin on cytosolic calcium ([Ca2+]i) levels in human prostate LNCaP and PC-3 cells as well as choriocarcinoma JEG-3 cells were investigated. In addition, the effects of melatonin on changes in [Ca2+]i in LNCaP, PC-3 and JEG-3 cells induced, respectively, by sex steroids, gastrin-releasing peptide (GRP) and insulin-like growth factor I (IGF-I) were also studied. Although melatonin was found to exert no effect on basal [Ca2+]i in LNCaP cells, it reduced, dose-dependently (5 nM to 50 µM), the Ca2+ influx into LNCaP cells induced by 1 µM 17ß-estradiol (E2) or 0.1 µM 5•-dihydrotestosterone (DHT). Interestingly, estrogen and androgen antagonists (tamoxifen and cyproterone acetate) failed to block the Ca2+ influx into LNCaP cells induced by E2 and DHT. Similar to the results obtained in LNCaP cells, melatonin did not affect the basal [Ca2+]i in PC-3 and JEG-3 cells. While the rise in [Ca2+]i induced by 1 nM GRP in PC-3 cells was abrogated by 5 x 10–10M melatonin, IGF-I (10–8M)-induced increase in [Ca2+]i in JEG-3 cells was inhibited by 5 x 10–7 M melatonin. Our data suggest that melatonin may interact with sex steroids, GRP and IGF-I, through changes in intracellular calcium, in the modulation of the proliferation of androgen-sensitive LNCaP prostate cancer cells, androgen-insensitive PC-3 prostate cancer cells and choriocarcinoma JEG-3 cells respectively. The work described in this abstract was partially supported by a research grant from the Research Grants Council of the Hong Kong Special Administrative Region, China (Project No. HKU 7069/ 99M).-
dc.languageengen_HK
dc.publisherS Karger AG. The Journal's web site is located at http://www.karger.com/NSGen_HK
dc.relation.ispartofBiological Signals and Receptorsen_HK
dc.rightsBiological Signals and Receptors. Copyright © S Karger AG.en_HK
dc.titleInhibition of hormone-/growth factor-induced rise in cytosolic free calcium ([Ca2+]i) in human prostate cancer and choriocarcinoma cells by melatonin.en_HK
dc.typeConference_Paperen_HK
dc.identifier.openurlhttp://library.hku.hk:4550/resserv?sid=HKU:IR&issn=1422-4933&volume=9&spage=68&epage=69&date=2000&atitle=Inhibition+of+hormone-/+growth+factor-induced+rise+in+cytosolic+free+calcium+([Ca2+]i)+in+human+prostate+cancer+and+choriocarcinoma+cells+by+melatonin.en_HK
dc.identifier.emailFong, SW: swanfong@graduate.hku.hken_HK
dc.identifier.emailShiu, SYW: sywshiu@hkucc.hku.hken_HK
dc.identifier.authorityShiu, SYW=rp00384en_HK
dc.identifier.doi10.1159/000014623-
dc.identifier.hkuros51409en_HK
dc.identifier.volume9en_HK
dc.identifier.issue1-
dc.identifier.spage68en_HK
dc.identifier.epage69en_HK

Export via OAI-PMH Interface in XML Formats


OR


Export to Other Non-XML Formats