Tumor pO2 as a Surrogate Marker to Identify Therapeutic Window during Metronomic Chemotherapy of 9L Gliomas

摘要

Abstract Glioblastomas are aggressive and highly vascularized primary brain tumors with a 5-year survival rate of less than 10%. Approaches targeting tumor vasculature are currently being investigated to achieve therapeutic benefits for this fatal malignancy. However, lack of suitable markers that can be used to monitor therapeutic effects during such treatments has restricted their optimization. We have focused on the development of tumor pO2 as a surrogate marker to identify the therapeutic window during metronomic chemotherapy. We report the effect of four weekly administrations of cyclophosphamide (140 mg/Kg, i.p), a chemo drug, on tumor pO2 and growth of subcutaneous 9L tumors in SCID mice. The repeated measurement of tumor pO2 was carried out using in vivo EPR oximetry.