In the latest issue of Cell Death and Disease (2013, 4: e741) an article of prof. Golab team has been published: GRP78-targeting subtilase cytotoxin sensitizes cancer cells to photodynamic therapy.
In this study prof. Golab’s team has shown for the first time that a catalytic subunit A of a bacterial subtilase cytotoxin fused to epidermal growth factor (EGF-SubA) sensitizes tumor cells to the cytotoxic effects of photodynamic therapy (PDT). SubA targets glucose-regulated protein 78 (GRP78), which resides in endoplasmic reticulum and participates in the regulation of endoplasmic reticulum stress. The team has observed that PDT induces increased levels of GRP78 in tumor cells. Knock-down of this protein sensitizes, while its stable overexpression confers resistance to PDT indicating that GRP78 plays a cytoprotective role. Prof. Golab’s team discovered that PDT and GRP78-targeting cytotoxin treatment can efficiently kill cancer cells independent on their apoptotic competence and triggers an atypical, non-apoptotic cell death.
The data published in this paper helps understanding the basic mechanisms of action of photodynamic therapy and delivers important contribution to the wider use of this therapy in clinical practice.
Authors of the article are: Małgorzta Firczuk, Magdalena Gabrysiak, Joanna Barankiewicz, Antoni Domagała, Dominika Nowis, Marek Kujawa, Ewa Jankowska-Steifer, Malgorzata Wachowska, Eliza Glodkowska-Mrowka, Barbara Korsak, Magdalena Winiarska and Jakub Golab.