In vitro activity: Cabazitaxel increases CYP3A enzyme activities in rat hepatocytes. The mean ex-vivo human plasma protein binding of Cabazitaxel is 91.6%. Cabazitaxel is rapidly and extensively metabolised in numerous metabolites. Cabazitaxel demonstrates activity in several murine and human resistant cell lines. With a 4-day exposure to cabazitaxel, cytotoxicity is noted with relatively low cabazitaxel concentrations. Cabazitaxel shows high antitumor activity in 3 human colorectal cell lines (HCT-116, HCT-8, and HT-29).

Cell Assay: The cytotoxicity of CBX-loaded ANs and free Cabazitaxel (CBX) is evaluated with MTT assay. Cells are seeded onto a 96-well plate at a density of 3000 cells per well and cultured for 24 h. CBX-loaded ANs and free CBX are diluted to predetermined concentrations with PBS and added into each well. Blank AN, AN-ICG and free CBX solvent (a mixture of Tween-80 and anhydrous alcohol) are added as well to different final concentrations. The incubation continued for another 48 hours. 20 μL MTT solutions (5 mg/mL in PBS) are added into each well and cells are incubated for another 4 hours under 37°C. Subsequently the medium is removed and 150 μL dimethyl sulphoxide (DMSO) is added to dissolve the purple formazan salt crystals. Then the absorbance is measured by a microplate reader at 490 nm. The cells treated with medium are evaluated as controls.