UMI-77, a specific Mcl-1 inhibitor (Ki: 490 nM), has selectivity over other members of Bcl-2 family.

UMI-77, administered intravenously at a dose of 60 mg/kg, exhibits single-dose antitumor activity in the BxPC-3 xenograft mouse model without damaging normal tissues.

UMI-77 activates the intrinsic apoptosis pathway and/or induces a conformational change in Bax, thereby promoting apoptosis in pancreatic cancer cells. It disrupts the interaction between cell Mcl-1 and BL-Noxa as well as the protein-protein interaction between Mcl-1 and Bax. UMI-77 inhibits the growth of various pancreatic cancer cell lines, including BxPC-3, Panc-1, MiaPaCa-2, AsPC-1, and Capan-2 cells, with IC50 values of 3.4/4.4/12.5/16.1/5.5 μM, respectively.

Fluorescence polarization (FP)-based binding assays: Based on the Kd values, the concentrations of the proteins used in the competitive binding experiments are 90 nM for Mcl-1, 40 nM for Bcl-w, 50 nM for Bcl-xL, 60 nM for Bcl-2, and 4 nM for A1/Bfl-1. The fluorescent probes, Flu-BID and FAM-BID are fixed at 2 nM for all assays except for A1/Bfl-1 where FAMBID is used at 1 nM. 5 μL of the tested compound in DMSO and 120 μL of protein/probe complex in the assay buffer (100 mM potassium phosphate, pH 7.5; 100 μg/ml bovine gamma globulin; 0.02% sodium azide) are added to assay plates (Microfluor 2Black), incubated at room temperature for 3 h and the polarization values (mP) are measured at an excitation wavelength at 485 nm and an emission wavelength at 530 nm using the plate reader Synergy H1Hybrid. IC50 values are determined by nonlinear regression fitting of the competition curves.

Human pancreatic cancer cell lines AsPC-1, BxPC-3, and Capan-2 are cultured in RPMI-1640 medium, whereas Panc-1 and MiaPaCa are cultured in Dulbeccos' Modified Eagle's Medium (DMEM), all supplemented with 10% FBS. The cell growth inhibition after treatment with increasing concentrations of the compounds is determined by WST-8 assay.(Only for Reference)