The Serine protease inhibitor superfamily consists of 16 clades of evolutionarily and structurally conserved proteins, many of which have protease inhibitory activity. Several of the SERPINs have been implicated in the development and spread of cancer, and we have shown that SERPINB3, a cysteine protease inhibitor that targets lysosomal cathepsins, is important for resistance to radiation. A main focus of the lab is to understand the critical roles of these proteins, namely the intracellular SERPINB3, in cancer pathogenesis and resistance to therapy.

SERPINB3 tagged with a photo-switchable protein Dendra2 that fluoresces under a green wavelength prior to photoactivation and red after. This system allows us to monitor levels and localization of SERPINB3 in the cell before and after different stimuli. (Markovina et al., unpublished)
Immunohistochemistry for SERPINB3 (brown) in cervix tumor microarray (top) and a close up of one tumor core (bottom). (Markovina et al., unpublished)