Cell experiment:

Cells are detached by Accutase and counted. 1×103 single BCSC1 and BCSC2 cells are seeded as triplicates in 50% Matrigel into individual wells of 24-well ultra-low attachment plates in serum-free MSC medium. After 7 days, spheres over 50 μm diameter are counted for QC6352- and QC6688-treated and control cells and spheres over 20 μm diameter are counted for paclitaxel-treated and control cells[2].

Animal experiment:

Mice: When tumors reach a palpable size of 3 mm3, mice are treated with vehicle (control) or QC6352. The inhibitor is administered daily to mice via oral gavage at 10 mg/kg. Control animals receive vehicle only. Animals are monitored twice weekly for weight and tumor growth[2].

QC6352 is a potent KDM4C inhibitor with an IC50 of 35 nM.

QC6352 is a potent KDM4C inhibitor with an IC50 of 35±8 nM[1]. In a concentration-dependent manner QC6352 dramatically reduces the anchorage-independent sphere-forming capacity of BCSC1 and BCSC2. QC6352 blocks proliferation and self-renewal of BCSCs. As shown by western blot analysis the protein levels of (Epidermal growth factor receptor) EGFR are reduced in both BCSC1 and BCSC2 upon treatment with QC6352[2].

QC6352 strongly affects tumor growth and final tumor weight of both BCSC1 and BCSC2 xenografts. Treatment with QC6352 is well tolerated and does not affect body weight of the mice. Results demonstrate that treatment with the KDM4 inhibitor QC6352 blocks BCSC xenograft tumor growth[2].

[1]. Chen YK, et al. Design of KDM4 Inhibitors with Antiproliferative Effects in Cancer Models. ACS Med Chem Lett. 2017 Jul 27;8(8):869-874. [2]. Metzger E, et al. KDM4 inhibition targets breast cancer stem-like cells. Cancer Res. 2017 Sep 7. pii: canres.1754.