Suzanne Conzen, MD

Professor Emeritus

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Mammary Epithelial Cell Survival Signaling Pathways and the Role of Ubiquitin Modification in Regulating Kinase Activity

Research Summary

My laboratory studies molecular pathways in mammary epithelial cells that initiate inappropriate survival under conditions that would normally induce apoptosis, such as growth factor deprivation, chemotherapy and radiation. We have identified a novel survival pathway in these cells that is initiated through GR activation. Using large-scale gene array analysis, we have further identified several genes that are regulated by GR activation and are implicated in both novel and known survival signaling pathways. We are currently dissecting the individual contributions of the GR-regulated gene products to the survival phenotype. Understanding the mechanism of action of GR-mediated survival is proving to be a useful model for increasing both the understanding of gene regulation by the GR and the identification of novel survival pathways relevant to epithelial cells. These pathways are expected to identify novel targets for inhibitors that can interrupt the development of epithelial cell cancers (by blocking premalignant cell survival) and/or increase sensitivity to cytotoxic agents by increasing apoptosis.

References

1. Pan D, Kocherginsky M, Conzen SD. Activation of the glucocorticoid receptor is associated with poor prognosis in estrogen receptor-negative breast cancer. Cancer Res. 2011 Oct 15;71(20):6360-70. Epub 2011 Aug 25.

2. Beta-blocker use is associated with improved relapse-free survival in patients with triple-negative breast cancer. Melhem-Bertrandt A, Chavez-Macgregor M, Lei X, Brown EN, Lee RT, Meric-Bernstam F, Sood AK, Conzen SD, Hortobagyi GN, Gonzalez-Angulo AM. J Clin Oncol. 2011 Jul 1;29(19):2645-52. Epub 2011 May 31.

3. Serum/glucocorticoid-regulated kinase 1 expression in primary human prostate cancers. Szmulewitz RZ, Chung E, Al-Ahmadie H, Daniel S, Kocherginsky M, Razmaria A, Zagaja GP, Brendler CB, Stadler WM, Conzen SD. Prostate. 2012 Feb 1;72(2):157-64.

4. Social isolation dysregulates endocrine and behavioral stress while increasing malignant burden of spontaneous mammary tumors. Hermes GL, Delgado B, Tretiakova M, Cavigelli SA, Krausz T, Conzen SD, McClintock MK. Proc Natl Acad Sci U S A. 2009 Dec 29;106(52):22393-8.

5. Wu W, Chaudhuri S, Brickley DR, Pang D, Karrison T, Conzen SD. Microarray analysis reveals glucocorticoid-regulated survival genes that are associated with inhibition of apoptosis in breast epithelial cells. Cancer Res. 2004; 64(5):1757-64.

6. Poelman SM, Heimann R, Fleming GF, Recant WM, Conzen SD. Invariant p53 immunostaining in primary and recurrent breast cancer. Eur J Cancer. 2004; 40(1):28-32.

7. Brickley DR, Mikosz CA, Hagan CR, Conzen SD.Ubiquitin modification of serum and glucocorticoid-induced protein kinase-1 (SGK-1).J Biol Chem. 2002; 277(45):43064-70.

8. Mikosz CA, Brickley DR, Sharkey MS, Moran TW, Conzen SD. Glucocorticoid receptor-mediated protection from apoptosis is associated with induction of the serine/threonine survival kinase gene, sgk-1. J Biol Chem. 2001; 276(20):16649-54.

9. Moran TJ, Gray S, Mikosz CA, Conzen SD. The glucocorticoid receptor mediates a survival signal in human mammary epithelial cells. Cancer Res. 2000; 60(4):867-72.