Prostate Cancer Scientific Abstracts - M. Daja

Welcome to the Prostate Cancer Guide scientific abstracts, author section M Daja.

This section is recommended for people who have a scientific interest in prostate cancer. It is recommended that people without prior knowledge of prostate cancer visit the more general areas of the site (Prostate Cancer Guide).

Selected M. Daja prostate cancer abstracts

Journal: prostate cancer and prostic diseases

Pubmed ID: 12664060

Authors: Daja MM, Niu X, Zhao Z, Brown JM, Russell PJ.

Title: Characterization of expression of matrix metalloproteinases and tissue inhibitors of metalloproteinases in prostate cancer cell lines.
Stromal expression of some matrix metalloproteinases (MMPs) has been associated with increasing tumour burden in prostate cancer. We investigated the expression of mRNA (by RT-PCR) and protein (by zymography and western blotting) of MMPs and endogenous inhibitors (tissue inhibitors of metalloproteinases, TIMPs) in two parent epithelial prostate cancer cell lines and sublines of increasing invasive/metastatic potential. Expression of membrane type MMPs, MT1-MMP and MT3-MMP mRNA was higher in PC3-derived than in LNCaP-derived lines, whereas MT2-MMP mRNA expression was higher in the LNCaPderived than in PC3-derived cell lines. Active MT1, MT2 and MT3-MMP protein levels were similar in all lines, but processed MT-MMPs, indicative of latent MMP activation, were increased in more aggressive sublines. Expression of MMP-1, MMP-13 and TIMP-1 was higher in the more aggressive sublines and may be implicated in invasive/metastatic ability. Regulation of MMP-1 and MMP-13 expression may offer important therapeutic options for treating patients with prostate cancer.

Contact: Oncology Research Centre, Prince of Wales Hospital, Sydney, and Department of Medicine, University of New South Wales, NSW, Australia.

p.russell@unsw.edu.au

Journal: Molecular Urology

Pubmed ID: 11156711

Authors: Daja MM, Aghmesheh M, Ow KT, Rohde PR, Barrow KD, Russell PJ.

Title: Beta-human chorionic gonadotropin in semen: a marker for early detection of prostate cancer?

The expression of the androgen receptor (AR) gene is regulated by androgens. Although androgens down-regulate AR mRNA in most cell lines and tissues, including the prostate, up-regulation occurs in some tissues. Androgen-mediated reduction in AR mRNA is reproduced in COS1 cells and in the androgen-sensitive human prostate cancer cell line LNCaP when each expresses the AR cDNA. We have previously established that the AR cDNA contains the requisite sequences for this down-regulation. Here we shown that androgen promoted up-regulation of AR mRNA in two androgen-independent human prostate cancer cell lines, PC3 and DU145, when each was transfected with a human AR cDNA. This effect was due to the AR cDNA and not to the heterologous promoter driving AR expression. In addition to up-regulation of AR mRNA, androgen induced comparable increases in AR protein levels in PC3 cells stably expressing an AR cDNA (PC3/AR). Up-regulation of AR in PC3/AR cells was accompanied by failure of these cells to undergo desensitization or inactivation of AR following prolonged (96 h) androgen administration, whereas the same conditions resulted in desensitization of AR transactivation in LNCaP cells and in CVl cells that stably express the AR cDNA. Androgen treatment of PC3/AR cells resulted in induction of an androgen-regulated reporter gene (MMTV-CAT) as well as the native prostate-specific antigen gene, which is silent in untransfected PC3 but is androgen up-regulated in LNCaP and in the prostate. These results suggest that ectopic expression of AR in androgen-independent prostate cancer cell lines establishes both typical and atypical androgenic responses in a target gene-specific manner. Androgenic up-regulation of AR cDNA expression may be due to distinct signaling mechanisms that influence androgen action in androgen-independent prostate cancer cells.