Quercetin Induces p53-Independent Apoptosis in Human Prostate Cancer Cells by Modulating Bcl-2-Related Proteins: A Possible Mediation by IGBP-3

M.R. Vijayababu, P. Kanagaraj, A. Arunkumar, R. Ilangovan, Arunasalam Dharmarajan, J. Arunakaran

    Research output: Contribution to journalArticle

    43 Citations (Scopus)

    Abstract

    Quercetin, a flavonoid found in onion, grapes, green vegetables, etc., has been shown to possess potent antiproliferative effects against various malignant cells. We report insulin-like growth factor-binding protein-3 (IGFBP-3) as an effector of quercetin-induced apoptosis in human prostate cancer cell lines in a p53-independent manner. We evaluated the production of IGFBP-3 in quercetin-treated cells. Apoptosis was studied in quercetin-treated cells to study the IGFBP-3-mediated role with flow cytometry and DNA fragmentation. Protein expressions of Bcl-2, Bcl-x(L), and Bax were studied by Western blot. Increased production of IGFBP-3 was associated with the increased ratio of proapoptotic to antiapoptotic members of the Bcl-2 family. In quercetin-treated PC-3 cells, an increase in Bax protein expression and a decrease in Bcl-x(L) protein and Bcl-2 protein were observed. As PC-3 is a p53-negative cell line, these modulations of proapoptotic proteins and induction of apoptosis were independent of p53. The level of IGFBP-3 on the response of PC-3 cells to quercetin was examined. There was a twofold increase in IGFBP-3 level in conditioned media of 100 mu M quercetin-treated cells. Quercetin also brought a peak at sub-G, in PC-3 cells. Thus, increased level of IGFBP-3 was associated with increased proapoptotic proteins and apoptosis in response to quercetin, suggesting it may be a p53-independent effector of apoptosis in prostate cancer cells via its modulation of the Bax/Bcl-2 protein ratio.
    Original languageEnglish
    Pages (from-to)67-74
    JournalOncology Research
    Volume16
    Issue number2
    Publication statusPublished - 2006

    Fingerprint Dive into the research topics of 'Quercetin Induces p53-Independent Apoptosis in Human Prostate Cancer Cells by Modulating Bcl-2-Related Proteins: A Possible Mediation by IGBP-3'. Together they form a unique fingerprint.

    Cite this