Harnessing the gatekeepers of glucocorticoids for chemoprevention of non-melanoma skin cancer.

Despite effective surgical methods for non-melanoma skin cancer (NMSC), patients suffer from tissue damage, scarring, or even disfigurement; thus, there is a need for chemopreventive approaches. Because of the complex interplay between glucocorticoids (GCs), inflammation, and cancer, we sought to determine the role of 11ß-hydroxysteroid dehydrogenase 1 and 2 (11ßHSD1 and 2) in regulating GCs during skin cancer development and progression. 11ßHSDs modulate the activation of GCs in a tissue-specific manner and have been reported to play a role in development and progression of other types of cancer, but their role has not yet been reported in NMSC. Here, we found a significant upregulation of 11ßHSD2 protein in skin cancer cells when compared to normal skin cells, suggesting a role for this enzyme in the multifactorial process of skin cancer development. In addition, inhibition of 11ßHSD2 with siRNA resulted in significant reduction in colony formation in vitro. Finally, our in vivo study elucidated that inhibition of 11ßHSD2 with pharmacological inhibitor, Glycyrrhetinic acid (GA) could significantly diminish tumorigenesis in a well-studied in vivo mouse model of NMSC. Overall, these studies highlight for the first time a potential novel role for 11ßHSD2 in NMSC development and may allow for new GC treatment approaches capable of avoiding deactivation by the enzyme. If 11ßHSD2 can be inhibited as we have done here, or circumvented using modified GCs, this may lead to more efficacious outcomes for NMSC patients by preventing deactivation of the GC and minimizing resistance.

Ursolic Acid and Chronic Disease: An Overview of UA's Effects On Prevention and Treatment of Obesity and Cancer.

Chronic diseases pose a worldwide problem and are only continuing to increase in incidence. Two major factors contributing to the increased incidence in chronic disease are a lack of physical activity and poor diet. As the link between diet and lifestyle and the increased incidence of chronic disease has been well established in the literature, novel preventive, and therapeutic methods should be aimed at naturally derived compounds such as ursolic acid (UA), the focus of this chapter. As chronic diseases, obesity and cancer share the common thread of inflammation and dysregulation of many related pathways, the focus here will be on these two chronic diseases. Significant evidence in the literature supports an important role for natural compounds such as UA in the prevention and treatment of chronic diseases like obesity and cancer, and here we have highlighted many of the ways UA has been shown to be a beneficial and versatile phytochemical.