Interestingly, we recently demonstrated that zinc supplementation is required for the drug-induced immunogenic cell Blasticidin S ic50 death in chemoresistant p53-functionally defective cancer cells [37] centering the 2 ideal goals of anticancer therapy that are the induction of a strong cytotoxic
response of tumor cells [38] and the stimulation of host tumor-specific response, cooperating in the achievement of clinically relevant effects [39]. Altogether, these findings emphasize the translational potential of zinc in clinical practice. Here we attempted to evaluate the effect of a novel Zinc(II) compound containing a 4,4′-disubstituted-2,2′-bipyridine as main ligand and curcumin and chloride as ancillary ligands [13, 14]. As for ZnCl2, Zn-curc modified the equilibrium between p53 mutant and wild-type conformation toward wild-type conformation, specifically affecting R175H and R273H mutant proteins. Differently from ZnCl2 of our previous studies though [9–12], Zn-curc was able to directly induce apoptotic cell death selleckchem likely due to p53 reactivation following both conformational changes and DNA damage induction, as evidenced by phosphorylation of histone γH2AX. Thus, Zn-curc metal complex combines DNA intercalating PI3K inhibitor ability and cytotoxic activity with fluorescence [13,
14]. This latter characteristic was in addition particularly useful in testing the capacity
of Zn-curc to reach the tumor site in vivo. To this purpose, we used the ortothopic mice model of glioblastoma whose treatment remains a challenge due to its location, aggressive biological behaviour, angiogenesis and diffuse infiltrative growth, other than to the existence of blood-tumor barrier (BTB) representing an obstacle to the therapeutic efficacy via systemic administration [16, 40]. Zn-curc was detected in the glioblastoma tissues, highlighting its capacity to reach the tumor site and affect molecular pathways Carnitine dehydrogenase important for tumor angiogenesis, and impairment of response to therapies such as VEGF, MDR1 and Bcl2. Targeting of such pathways might be important for restoring the response to anticancer therapies [41]. In summary, in this study we described the antitumor effect of a novel compound which combines the Zn(II) ability to reactivate some tumor specific p53 mutations with cytotoxic activity (due to its DNA intercalating ability) and fluorescence feature (due to the curcumin moiety). This Zn-curc complex might be useful in developing efficient anticancer drugs becuase (i) its ability to target one of the most common p53 mis-sense mutant, that is R1775H (http://www-p53.iarc.fr), (ii) its cytotoxic effect specific for tumor cells, and (iii) its capacity to cross the BTB when systematically administered.