The chemokine growth-regulated oncogene 1 (Gro-1) links RAS signaling to the senescence of stromal fibroblasts and ovarian tumorigenesis.

Abstract

Epithelial-stromal interactions play a critical role in tumor initiation and progression; cancer-associated stroma, but not normal stroma, is known to be tumor-promoting. However, the molecular signal used by epithelial cancer cells to reprogram normal stroma to a tumorigenic stroma is not known. Here, we present evidence to suggest that the chemokine growth-regulated oncogene 1 (Gro-1) may be one such signaling molecule. We showed that the expression of Gro-1 is activated by RAS and is vital for cell survival and the malignant transformation of ovarian epithelial cells. Surprisingly, we found that Gro-1 is a potent inducer of senescence in stromal fibroblasts and that this effect depends on functional p53. Senescent fibroblasts induced by Gro-1 can promote tumor growth whereas abrogation of senescence through immortalization results in loss of such tumor promoting activity. We also demonstrated that stromal fibroblasts adjacent to epithelial cancer cells are senescent in human ovarian cancer specimens and in heterografts from RAS-transformed human ovarian epithelial cells and ovarian cancer cells. Moreover, Gro-1 was expressed at significantly higher amounts in ovarian cancer than in normal tissues and was higher in serum samples from women with ovarian cancer than in serum from women without ovarian cancer. These findings provide strong evidence that RAS-induced Gro-1 can reprogram the stromal microenvironment through the induction of senescence of fibroblasts and thus can promote tumorigenesis. Therefore, Gro-1 may be a therapeutic target as well as a diagnostic marker in ovarian cancer.

• Authors: Gong Yang, Daniel G Rosen, Zhihong Zhang, Robert C Bast Jr, Gordon B Mills, Justin A Colacino, Imelda Mercado-Uribe, Jinsong Liu
• Journal: Proceedings of the National Academy of Sciences of the United States of America (Proc Natl Acad Sci U S A) Vol. 103 Issue 44 Pg. 16472-7 (Oct 31 2006) ISSN: 0027-8424 [Print] United States
• PMID: 17060621 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Biomarkers
• CXCL1 protein, human
• Chemokine CXCL1
• Chemokines, CXC
• Tumor Suppressor Protein p53
• ras Proteins

Topics

• Apoptosis
• Biomarkers
• Cell Transformation, Neoplastic (genetics, metabolism, pathology)
• Cells, Cultured
• Cellular Senescence (physiology)
• Chemokine CXCL1
• Chemokines, CXC (genetics, metabolism)
• Female
• Fibroblasts (cytology)
• Gene Expression Regulation
• Humans
• Ovarian Neoplasms (genetics, metabolism, pathology)
• Signal Transduction
• Stromal Cells (cytology, pathology)
• Tumor Suppressor Protein p53 (metabolism)
• ras Proteins (genetics, metabolism)