TY - JOUR
T1 - Oxazoloisoindolinones with in vitro antitumor activity selectively activate a p53-pathway through potential inhibition of the p53-MDM2 interaction
AU - Soares, Joana
AU - Pereira, Nuno A.L.
AU - Monteiro, Ângelo
AU - Leão, Mariana
AU - Bessa, Cláudia
AU - Dos Santos, Daniel J.V.A.
AU - Raimundo, Liliana
AU - Queiroz, Glória
AU - Bisio, Alessandra
AU - Inga, Alberto
AU - Pereira, Clara
AU - Santos, Maria M.M.
AU - Saraiva, Lucília
N1 - Publisher Copyright:
© 2014 Elsevier B.V. All rights reserved.
PY - 2015/1/23
Y1 - 2015/1/23
N2 - One of the most appealing targets for anticancer treatment is the p53 tumor suppressor protein. In half of human cancers, this protein is inactivated due to endogenous negative regulators such as MDM2. Actually, restoring the p53 activity, particularly through the inhibition of its interaction with MDM2, is considered a valuable therapeutic strategy against cancers with a wild-type p53 status. In this work, we report the synthesis of nine enantiopure phenylalaninol-derived oxazolopyrrolidone lactams and the evaluation of their biological effects as p53-MDM2 interaction inhibitors. Using a yeast-based screening assay, two oxazoloisoindolinones, compounds 1b and 3a, were identified as potential p53-MDM2 interaction inhibitors. The molecular mechanism of oxazoloisoindolinone 3a was further validated in human colon adenocarcinoma HCT116 cells with wild-type p53 (HCT116 p53+/+) and in its isogenic derivative without p53 (HCT116 p53-/-). Indeed, using these cells, we demonstrated that oxazoloisoindolinone 3a exhibited a p53-dependent in vitro antitumor activity through induction of G0/G1-phase cell cycle arrest and apoptosis. The selective activation of a p53-apoptotic pathway by oxazoloisoindolinone 3a was further supported by the occurrence of PARP cleavage only in p53-expressing HCT116 cells. Moreover, oxazoloisoindolinone 3a led to p53 protein stabilization and to the up-regulation of p53 transcriptional activity with increased expression levels of several p53 target genes, as p21(WAF1/CIP1), MDM2, BAX and PUMA, in p53+/+ but not in p53-/- HCT116 cells. Additionally, the ability of oxazoloisoindolinone 3a to block the p53-MDM2 interaction in HCT116 p53+/+ cells was confirmed by co-immunoprecipitation. Finally, the molecular docking analysis of the interactions between the synthesized compounds and MDM2 revealed that oxazoloisoindolinone 3a binds to MDM2. Altogether, this work adds, for the first time, the oxazoloisoindolinone scaffold to the list of chemotypes activators of a wild-type p53-pathway with promising antitumor activity. Moreover, it may open the way to the development of a new class of p53-MDM2 interaction inhibitors.
AB - One of the most appealing targets for anticancer treatment is the p53 tumor suppressor protein. In half of human cancers, this protein is inactivated due to endogenous negative regulators such as MDM2. Actually, restoring the p53 activity, particularly through the inhibition of its interaction with MDM2, is considered a valuable therapeutic strategy against cancers with a wild-type p53 status. In this work, we report the synthesis of nine enantiopure phenylalaninol-derived oxazolopyrrolidone lactams and the evaluation of their biological effects as p53-MDM2 interaction inhibitors. Using a yeast-based screening assay, two oxazoloisoindolinones, compounds 1b and 3a, were identified as potential p53-MDM2 interaction inhibitors. The molecular mechanism of oxazoloisoindolinone 3a was further validated in human colon adenocarcinoma HCT116 cells with wild-type p53 (HCT116 p53+/+) and in its isogenic derivative without p53 (HCT116 p53-/-). Indeed, using these cells, we demonstrated that oxazoloisoindolinone 3a exhibited a p53-dependent in vitro antitumor activity through induction of G0/G1-phase cell cycle arrest and apoptosis. The selective activation of a p53-apoptotic pathway by oxazoloisoindolinone 3a was further supported by the occurrence of PARP cleavage only in p53-expressing HCT116 cells. Moreover, oxazoloisoindolinone 3a led to p53 protein stabilization and to the up-regulation of p53 transcriptional activity with increased expression levels of several p53 target genes, as p21(WAF1/CIP1), MDM2, BAX and PUMA, in p53+/+ but not in p53-/- HCT116 cells. Additionally, the ability of oxazoloisoindolinone 3a to block the p53-MDM2 interaction in HCT116 p53+/+ cells was confirmed by co-immunoprecipitation. Finally, the molecular docking analysis of the interactions between the synthesized compounds and MDM2 revealed that oxazoloisoindolinone 3a binds to MDM2. Altogether, this work adds, for the first time, the oxazoloisoindolinone scaffold to the list of chemotypes activators of a wild-type p53-pathway with promising antitumor activity. Moreover, it may open the way to the development of a new class of p53-MDM2 interaction inhibitors.
KW - Antitumor activity
KW - Docking analysis
KW - Yeast-based assay
KW - p53
KW - p53-MDM2 interaction/Oxazoloisoindolinones
UR - http://www.scopus.com/inward/record.url?scp=84908509142&partnerID=8YFLogxK
U2 - 10.1016/j.ejps.2014.10.006
DO - 10.1016/j.ejps.2014.10.006
M3 - Article
C2 - 25312347
AN - SCOPUS:84908509142
SN - 0928-0987
VL - 66
SP - 138
EP - 147
JO - European Journal of Pharmaceutical Sciences
JF - European Journal of Pharmaceutical Sciences
ER -