Class I phosphoinositide 3-kinase (PI3K) activate fundamental pathways controlling cell survival, metabolism, proliferation and and therefore play crucial role in cancer development. It is reported that p110γ is mainly expressed in leukocytes, whose role in cancer development is recently starting to be studied. CAL-130 is a specific dual inhibitor of p110γ and p110δ. In vitro: To demonstrate that CAL-130 can block the activities of both PI3Kγ and PI3Kδ in thymocytes, previous autors evaluated its ability of preventing phosphorylation of Akt (Ser473) and calcium flux in response to T cell receptor (TCR). Consistently, CAL-130 treated thymocytes from 6-week-old WT animals prevented TCR-induced Akt phosphorylation and attenuated calcium flux to levels observed for their Pik3cγ-/-; Pik3cδ-/- counterparts [1]. In vivo: To assess the in vivo efficacy, previous study determined its effects on 6-week-old WT mice thymi. Mice orally received 10 mg/kg of the inhibitor, which was sufficient to maintain plasma concentrations of 0.33 μM at the end of 8 hrs. Moreover, such dose did not affect either plasma glucose or insulin levels. In contrast, CAL-130 treatment (10 mg/kg every 8 hrs) for a period of 7 days greatly affected the size, cellularity, and overall architecture of the thymus. Notely there was a 18-fold reduction in total thymocyte number when comparred to controls, which was mainly due to the DP population loss [1]. Clinical trial: CAL-130 is currently in the preclinical developlent stage and no clinical data are available. Reference: [1] Subramaniam PS, Whye DW, Efimenko E, Chen J, Tosello V, De Keersmaecker K, Kashishian A, Thompson MA, Castillo M, Cordon-Cardo C, Davé UP, Ferrando A, Lannutti BJ, Diacovo TG. Targeting nonclassical oncogenes for therapy in T-ALL. Cancer Cell. 2012;21(4):459-72.
