Evaluation of histone deacetylase inhibitor substituted zinc and indium phthalocyanines for chemo- and photodynamic therapy

In this study, we synthesized and characterized 3-hydroxypyridin-2-thione (3-HPT) bearing zinc ( ZnPc-1 and ZnPc-2 ) and indium ( InPc-1 and InPc-2 ) phthalocyanine (Pc) derivatives, either non-peripherally or peripherally substituted as photosensitizer (PS) agents and evaluated their anti-cancer efficacy on two breast cancer cell lines, MDA-MB-231 and MCF-7 as well as a human endothelial cell line, HUVEC. Our results indicated different localization patterns between ZnPcs and InPcs in addition to enhanced effects on the mitochondrial network for InPcs . Moreover, peripheral or non-peripheral substitution of HDACi moieties altered cellular localization between ZnPc-1 and ZnPc-2 , leading to increased IC 50 values along with decreased anti-cancer activity for non-peripheral substitution. When considering the compounds' differential effects in vitro , our data indicates that further research is required to determine the ideal Pcs for anti-cancer PDT treatments since the core metals of the compounds have affected the cellular localization, and positioning of the chemotherapeutic residues may inhibit cellular penetrance. 3-Hydroxypyridin-2-thione bearing zinc and indium phthalocyanine derivatives, as photosensitizer agents have been synthesized and evaluated for their anti-cancer efficacy on two breast cancer cell lines, MDA-MB-231 and MCF-7 as well as a human endothelial cell line, HUVEC.