Urinary bioorthogonal reporters for the monitoring of the efficacy of chemotherapy for lung cancer and of associated kidney injury

The utility of urinary tests for the monitoring of the treatment efficacy and adverse events of anticancer therapies is constrained by the low concentration of relevant urinary biomarkers. Here we report, using mice with lung cancer and treated with chemotherapy, of a urinary fluorescence test for the concurrent monitoring of the levels of a tumour biomarker (cathepsin B) and of a biomarker of chemotherapy-induced kidney injury (N-acetyl-β-d-glucosaminidase). The test involves two intratracheally administered urinary reporters leveraging caged bioorthogonal click handles for the biomarker-dependent activation of ‘clickability’ and renal clearance, and the bioorthogonal click reaction of each renally cleared reporter with paired fluorescence indicators in the collected urine. In mouse models of chemotherapy-treated orthotopic lung cancer and of cisplatin-induced kidney injury, lower urinary fluorescence signals (which can be measured by a smartphone camera) for tumour and kidney injury levels positively correlated with animal weight gain and survival time. Biomarker-activated bioorthogonal click reactivity and renal clearance combined with bioorthogonally triggered fluorescence in vitro may enable specific, sensitive and rapid urinary assays for the monitoring of other physiopathological processes.