|
|
|
|
|
|
|
Free Newsletters
Archive
My Subscriptions

News by Subject
News by Disease
News by Date
PLoS
Search News
Post Your News
JoVE

Job Seeker Login
Most Recent Jobs
Browse Biotech Jobs
Search Jobs
Post Resume
Career Fairs
Career Resources
For Employers

Regional News
US & Canada
Biotech Bay
Biotech Beach
Genetown
Pharm Country
BioCapital
BioMidwest
Bio NC
BioForest
Southern Pharm
BioCanada East
US Device
Europe
Asia


Market Summary
News
IPOs

Company Profiles

Companies
Events

Research Store

Biotech Events
Post an Event

Real Estate
Business Opportunities
|
|
|
|
|
PLoS By Category | Recent
PLoS Articles
|
|
Chemistry - Oncology - Urology
|
Kava Components Down-Regulate Expression of AR and AR Splice Variants and Reduce Growth in Patient-Derived Prostate Cancer Xenografts in Mice
Published:
Thursday, February 09, 2012
Author:
Xuesen Li et al.
by Xuesen Li, Zhongbo Liu, Xia Xu, Christopher A. Blair, Zheng Sun, Jun Xie, Michael B. Lilly, Xiaolin Zi
Men living in Fiji and drinking kava have low incidence of prostate cancer (PCa). However, the PCa incidence among Fijian men who had migrated to Australia, increased by 5.1-fold. We therefore examined the potential effects of kava root extracts and its active components (kavalactones and flavokawains) on PCa growth and androgen receptor (AR) expression. PCa cell lines (LNCaP, LAPC-4, 22Rv1, C4-2B, DU145 and PC-3) with different AR expression, and a transformed prostate myofibroblast cell line (WPMY-1), were treated with a commercial kava extract, kavalactones (kawain, 5'6'-dehydrokawain, yangonin, methysticin) and flavokawain B. Expression of AR and its target genes (PSA and TMPRSS2) was examined. Two novel patient-derived PCa xenograft models from high grade PCa specimens were established by implanting the specimens into nude mice and passing tumor pieces through subcutaneous injection in nude mice, and then treated with kava extract and flavokawain B to examine their effects on tumor growth, AR expression and serum PSA levels. The kava extract and flavokawain B effectively down-regulated the expression of both the full-length AR and AR splice variants. The kava extract and kavalactones accelerated AR protein degradation, while flavokawain B inhibited AR mRNA transcription via decreasing Sp1 expression and the binding of Sp1 to the AR promoter. The kava root extract and flavokawain B reduce tumor growth, AR expression in tumor tissues and levels of serum PSA in the patient-derived PCa xenograft models. These results suggest a potential usefulness of a safe kava product or its active components for prevention and treatment of advanced PCa by targeting AR.
More...
|
|
|
 |
 |
|
|
|
|
|
|
|
|