Animal experiment:

Female WT BALB/c mice are orthotopically inoculated in the mammary fat pad on day 0 with 1×105 4T1 cells. Drug (75 mg/kg PI-3065, once daily) or vehicle (0.5% methylcellulose with 0.2% Tween 80) is administered by oral gavage from day -1 (administered 12 h prior to tumour cell inoculation). Tumour growth is monitored weekly by caliper measurement or by measuring luminescence using a Xenogen imaging platform. On day 35, mice are euthanized, tumours and peripheral organs extracted for in vitro luminescence measurement, followed by fixation in 4% PFA and H&E staining. KPC mice are allowed to develop advanced lesions of 5-10 mm (determined by ultrasound imaging) before treatment with vehicle or PI-3065 for a total of 14 days.

PI-3065 is a small molecule and selective inhibitor of p110δkinase with an Ki value of 1.5nM and IC50 value of 5nM [1].

PI-3065 has been reported to selectively inhibit p110δkinase with Ki values of 15nM, 110nM, 130nM and 940nM, IC50 values of 5nM, 91nM, 600nM and >10000nM for p110δ, p110α, p110β and p110γ, respectively. In addition, PI-3065 has been revealed to inhibit 4T1 tumour growth and metastasis. PI-3065 has also noted to prolong survival and reduce the incidence of macroscopic metastases and other disease-associated pathologies [1].

References:
[1] Ali K1, Soond DR2, Pi?eiro R1, Hagemann T3, Pearce W4, Lim EL5, Bouabe H5, Scudamore CL6, Hancox T7, Maecker H8, Friedman L8, Turner M5, Okkenhaug K9, Vanhaesebroeck B1. Inactivation of PI(3)K p110δ breaks regulatory T-cell-mediated immune tolerance to cancer. Nature. 2014 Jun 19;510(7505):407-11. doi: 10.1038/nature13444. Epub 2014 Jun 11.