Glutathione transferase omega 1-1 (GSTO1-1) can effect the inter-cell transfer of cisplatin resistance through the exosomal route

Glutathione transferase omega-1-1 (GSTO1-1) is a member of the glutathione transferase superfamily (GSTs) involved in the modulation of cell survival, proliferation and metabolism. Increased levels of GSTO1-1 have been associated with cancer progression and chemoresistance in different types of cancer cells, possibly supported by the post-traslational regulation of some major prosurvival pathways regulated by the enzyme. Our data demonstrate for the first time that GSTO1-1 can be released by cancer cells through the exosomal route and transferred to GSTO1-1 knock-out cells, this resulting in an increased resistance against cisplatin toxicity in recipient cells. The use of the exosomal route to transfer the regulatory competences of GSTO1-1 could be a further element supporting its role in neoplastic progression.