Journal
BIOCHEMICAL PHARMACOLOGY
Volume 74, Issue 9, Pages 1340-1349Publisher
PERGAMON-ELSEVIER SCIENCE LTD
DOI: 10.1016/j.bcp.2007.07.016
Keywords
prodigiosin; p21; cell cycle arrest; TGF-beta; NAG-1; breast cancer
Categories
Ask authors/readers for more resources
The anticancer agent prodigiosin has been shown to act as an efficient immunosuppressant, eliciting cell cycle arrest at non-cytotoxic concentrations, and potent proapoptotic and antimetastatic effects at higher concentrations. Gene expression profiling of MCF-7 cells after treatment with a non-cytotoxic concentration of prodigiosin showed that expression of the p21(WAF1/CIP1) gene, a negative cell cycle regulator was induced. In this study, we show that prodigiosin induces p21 expression leading to cell cycle blockade. Subsequently, we attempted to elucidate the molecular mechanisms involved in prodigiosin-mediated p21 gene expression. We demonstrate that prodigiosin induces p21 in a p53-independent manner as prodigiosin induced p21 in cells with both mutated and dominant negative p53. Conversely, the transforming growth factor-beta (TGF-beta) pathway has been found to be necessary for p21 induction. Prodigiosin-mediated p21 expression was blocked by SB431542, a TGF-P receptor inhibitor. Nevertheless, this pathway alone is not enough to induce p21 expression. The TGF-P family member (nonsteroidal anti-inflammatory drug)-activated gene 1/growth differentiation factor 15 (NAG-1) may activate this pathway, as it has previouslybeen suggested to signal through the TGF-beta pathway and is overexpressed in response to prodigiosin treatment. We show that NAG-1 colocalizes with TGF-P receptor type 1, suggesting a possible interaction between them. Taken together, these results suggest the TGF-P pathway is required for induction of p21 expression after prodigiosin treatment of MCF-7 cells. (C) 2007 Elsevier Inc. All rights reserved.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available