Direct Readout Hypoxia Tumor Suppression In Vivo through NIR-Theranostic Activation.

Urgency in finding a suitable therapy in tumor hypoxia strives to develop hypoxia-targeted activatable theranostic. A strategic theranostic prodrug () has been synthesized. Its azo-linker scission under the hypoxia condition has released an near-infrared (NIR)-reporter to determine the extent of chemotherapeutic (melphalan analogue) activation. Under an artificial hypoxia condition, a large shift from 520 to 590 nm in UV absorption was observed in . Alongside, the emission maxima had appeared at 625 nm under the said condition. The post-incubated HeLa cells have shown upregulation of various apoptotic factors under oxygen deprivation (3%) condition. has shown antiproliferative activity under hypoxia conditions in various cancer cells. An ex-vivo biodistribution study indicated that theranostic only activated in tumor tissue and to some extent in the liver. The therapeutic activity study in vivo indicated that effectively reduced the tumor size and volume (about 2-fold) without the change of bodyweight of mice. The theranostic can be a cornerstone to suppress tumor hypoxia and tracking its extent of suppression.