The major consequence of core mutation is loss of sequence-specific DNA binding to the canonical wtp53-binding site of target genes with loss of p53

oncosuppressor function. In some cases though, mtp53 proteins may acquire pro-oncogenic functions contributing to tumor progression [5]; moreover, loss of the ability of mtp53 to induce the expression of the E3-ubiquitin ligase MDM2 is thought to be responsible for the mtp53 enhanced stability [6]. These observations, and the finding that mtp53 protein is often expressed at high levels in tumors, make mtp53 reactivation an attractive strategy as anticancer therapy [7]. Many screening studies are underway to identify small molecules that reactivate mtp53 by acting on the equilibrium of native and denatured protein immediately OICR-9429 in vivo Target Selective Inhibitor Library concentration after translation, by acting on the misfolded states, or by alleviating the mtp53 pro-oncogenic affects (i.e., mutp53/p73 interaction) [5, 7, 8]. In previous studies we found that ZnCl2 treatment induced the transition of mutant p53 protein into a functional conformation [9–12]. Although we found that ZnCl2 treatment did not induce cell death by itself,

it restored mt-p53-carrying cell sensitivity to chemotherapy allowing tumor regression [9–12]. Here we aimed at examine the effect of a novel Zinc compound, a heteroleptic pentacoordinated (bpy-9)Zn(curc, Cl) complex (hereafter indicated as Zn-curc) containing a 4,4’-disubstituted-2,2′-bipyridine as main ligand and curcumin (curc) and chloride (Cl) as ancillary ligands Fossariinae [13, 14], in mutant p53-carrying cancer cells. The presence of the curcumin framework in the Zn-curc complex allows intrinsic fluorescence

activity, therefore we attempted to exploit this feature to evaluate the intratumoral distribution of Zn-curc in an ortothopic model of glioblastoma in mice. We choose to use glioblastoma because it is the most common and lethal primary central nervous system (CNS) where inactivation of the p53 gene and the presence of aberrant p53 expression are often reported [15]. Moreover, glioblastoma presents unique challenges to therapy due to its location, aggressive biological behaviour, angiogenesis and diffuse infiltrative growth. Thus, glioblastoma becomes easily chemoresistant, besides, the existence of blood-tumor barrier (BTB) represents an obstacle influencing the therapeutic efficacies via systemic administration [16]. In this study, we analyzed the biological effect of the novel Zn-curc complex in several cancer cell lines carrying different p53 mutations. Immunoprecipitation studies with conformation-specific antibodies were performed to evaluate p53 protein conformation after treatment. Finally, immunofluorescence analysis of glioblastoma tissues, of an ortothopic mice model treated with Zn-curc, was performed lo look for Zn-curc localization.