In our previous findings, when compared to a GBM tumor cell line that was propagated under normoxic conditions (pO2 = 20%) in the same study, our activatable NIR fluorescent smart probe afforded a remarkable 12‐fold OFF‐ON NIR fluorescence enhancement from NTR activity in such cells that experienced pathological hypoxic (pO2 ≤ 1.0%) and radiobiological hypoxic conditions (pO2 ≤ 0.5%) due to such cells being propagated under extreme hypoxic conditions (pO2 = 0.5%). Here, NTSR1 is linked to glioblastoma.