Research Overview

The Hammes laboratory is interested in steroid hormone production and signaling, with a focus on reproductive and cancer biology. His laboratory was one of the pioneers in the field of extranuclear, or “nongenomic,” steroid signaling, demonstrating the biological importance of crosstalk between rapid extranuclear kinase steroid effects and slower intranuclear transcriptional steroid actions, both of which are regulated by classical steroid receptors located near the plasma membrane or within the nucleus, respectively. Specifically, the laboratory has focused on the androgen receptor, and has mapped out important extranuclear signaling pathways that involve crosstalk with receptor tyrosine kinases, G proteins, cytoskeletal scaffold proteins, and transcriptional co-regulators. We have shown that these pathways are critical mediators of androgen actions both in many different tissues and organs within the body.

For example, using knockout models and sophisticated in-vitro strategies, the Hammes laboratory has demonstrated the importance of androgen signaling, both extranuclear and intranuclear, in normal ovarian function. They have found that normal follicle development and ovulation requires a very specific concentration of androgens in the ovary – too much androgen production leads to excessive follicle growth, as seen in polycystic ovary syndrome (PCOS), while too little androgen production leads to premature ovarian failure (POF).

In recent years, our laboratory has focused on steroid actions in various cancers, including androgen-sensitive prostate cancer and the rare estrogen-sensitive cancer called lymphangioleiomyomatosis. Our goals are to better understand how these cancers are regulated by steroid hormones and how, with time, steroid-sensitive cancer become steroid-independent. We are also interested in elucidating the role of inflammation in cancer growth, with a focus on neutrophils and related myeloid-derived suppressor cells (MDSCs). By delineating these pathways and interactions, our ultimate goal is to discover novel approaches toward treating cancer.