CYC065

Cell experiment:

The effect of CYC065 on the viability and IC50 of USC-ARK-1, USC-ARK-2, USC-ARK-7, USC-ARK-4 and USC-ARK-6 USC primary cell lines is determined in flow-cytometry assay. Briefly, tumour cells are plated in six-well plates and treated with a titration of CYC065 concentrations (i.e., ranging from 100 to 500 nM). After 72 h, cells are harvested, washed and stained with propidium iodide (PI; 5 μg/mL) for flow cytometric counts. The percentage of viable cells is then normalised considering the vehicle-treated cells as 100% viable. Half-maximal inhibitory concentration values are determined using GraphPad Prism5 version 6. For drug combination studies, USC-ARK-1 and USC-ARK-2 cell lines are incubated with the combination of Taselisib and CYC065 at multiple paired concentrations including the IC50, the IC50/2 and the IC50*2 of each cell line to the corresponding drug (i.e., 10 nM of Taselisib and 198 nM of CYC065 for USC-ARK-1 and 50 nM of Taselisib and 62.5 nM of CYC065 for USC-ARK-2). Synergism is assessed by the combination index (CI). CI values <1 define a synergistic activity of the combination treatment. The CI values are calculated using the CompuSyn software[1].

Animal experiment:

Mice[1] The in vivo efficacy of CYC065 used as a single agent is evaluated on xenograft mouse models derived from the CCNE1-amplified USC-ARK-2 USC cell line. Xenografts derived from the CCNE1-amplified, PIK3CA-mutated USC-ARK-1 cell line are used for evaluating the in vivo combination of CYC065 and Taselisib. Briefly, 5-7-week-old SCID mice are injected into the subcutaneous region with USC cells. A minimum of five animals per group are used. Treatments are administrated by oral gavage starting 1 week after tumor implantation when the size of the tumor is 0.125-0.150 cm3. Uterine serous carcinoma-ARK-2-derived xenografts are divided into two groups: one group of animal receive the vehicle, whereas the experimental group receive CYC065 (22.5 mg/kg daily for 3 weeks). Uterine serous carcinoma-ARK-1-derived xenografts are instead divided into four groups: one group receive the vehicle (0.5% methylcellulose-0.2% Tween-80), one group receive CYC065 (22.5 mg/kg daily for 3 weeks), one group receive Taselisib (10 mg/kg daily, 5 days per week per 3 weeks) and the last group receive the combination of CYC065 and Taselisib. The size of the tumor at the initiation of treatment is 0.125-0.150 cm3. Mouse weight and tumor size is recorded two times a week for the entire experimental period. Tumor volume is calculated.

References:

[1]. Cocco E, et al. Dual CCNE1/PIK3CA targeting is synergistic in CCNE1-amplified/PIK3CA-mutated uterine serous carcinomas in vitro and in vivo. Br J Cancer. 2016 Jul 26;115(3):303-11.
[2]. Sumana Devata, et al. Molecular markers and venous thromboembolism (VTE) in acute myelogenous leukemia (AML)