ABSTRACT
Cervical cancer is a leading cause of cancer-related deaths among women in developing countries. Therefore, development of new chemotherapeutic agents is required. Unlike normal cells, cancer cells contain elevated copper levels which play an integral role in angiogenesis. Thus, targeting copper via copper-specific chelators in cancer cells can serve as effective anticancer strategy. In this work, a copper chelator pregnenolone acetate nucleus-based tetrazole derivative (ligand-L) was synthesized and characterized by elemental analysis, ESI-MS, 1H NMR and 13C NMR. DNA binding ability of ligand-L was studied using UV-Vis and fluorescence spectroscopy. Fluorescence spectroscopy studies reveal that quenching constant of ligand-l-DNA and ligand-L-Cu(II) were found to be 7.4â¯×â¯103 M-1 and 8.8â¯×â¯103 M-1, respectively. In vitro toxicity of ligand-L was studied on human cervical cancer C33A cancer cells. Results showed that ligand-L exhibit significant cytotoxic activity against cervical cancer C33A cells with IC50 value 5.0⯱â¯1.8⯵M. Further, it was found that ligand-L cytotoxicity is due to redox cycling of copper to generate ROS which leads to DNA damage and apoptosis. In conclusion, this is the report where we synthesized pregnenolone acetate-based tetrazole derivative against C33A cells that targets cellular copper to induce pro-oxidant death in cancer cells. These findings will provide significant insights into the development of new chemical molecules with better copper chelating and pro-oxidant properties against cancer cells.
Subject(s)
Antineoplastic Agents/pharmacology , Apoptosis/drug effects , Chelating Agents/pharmacology , Organometallic Compounds/pharmacology , Reactive Oxygen Species/metabolism , Uterine Cervical Neoplasms/drug therapy , Acetates/chemistry , Acetates/pharmacology , Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/chemistry , Cell Proliferation/drug effects , Cell Survival/drug effects , Chelating Agents/chemical synthesis , Chelating Agents/chemistry , Copper/chemistry , Copper/pharmacology , DNA Cleavage/drug effects , Dose-Response Relationship, Drug , Drug Screening Assays, Antitumor , Female , Humans , Ligands , Molecular Structure , Organometallic Compounds/chemical synthesis , Organometallic Compounds/chemistry , Pregnenolone/chemistry , Pregnenolone/pharmacology , Structure-Activity Relationship , Tumor Cells, Cultured , Uterine Cervical Neoplasms/metabolism , Uterine Cervical Neoplasms/pathologyABSTRACT
Existing cancer therapies are often associated with drug resistance and toxicity, which results in poor prognosis and recurrence of cancer. This necessitates the identification and development of novel therapeutics against existing as well as novel cellular targets. In this study, a novel class of Benzocoumarin-Stilbene hybrid molecules were synthesized and evaluated for their antiproliferative activity against various cancer cell lines followed by in vivo antitumor activity in a mouse model of cancer. The most promising molecule among the series, i.e. compound (E)-4-(3,5-dimethoxystyryl)-2H-benzo[h]chromen-2-one (19) showed maximum antiproliferative activity in breast cancer cell lines (MDA-MB-231 and 4T1) and decreased the tumor size in the in-vivo 4T1 cell-induced orthotopic syngeneic mouse breast cancer model. The mechanistic studies of compound 19 by various biochemical, cell biology and biophysical approaches suggest that the compound binds to and inhibits the human DNA ligase I enzyme activity that might be the cause for significant reduction in tumor growth and may constitute a promising next-generation therapy against breast cancers.
Subject(s)
Anthracenes , Antineoplastic Agents/chemistry , Antineoplastic Agents/pharmacology , DNA Ligase ATP/antagonists & inhibitors , Enzyme Inhibitors/chemistry , Enzyme Inhibitors/pharmacology , Stilbenes , Animals , Anthracenes/chemistry , Apoptosis/drug effects , Breast Neoplasms , Cell Cycle Checkpoints/drug effects , Cell Line, Tumor , Cell Proliferation/drug effects , DNA Damage , Disease Models, Animal , Female , Humans , Mice , Molecular Structure , Signal Transduction/drug effects , Stilbenes/chemistry , Xenograft Model Antitumor AssaysABSTRACT
Recent studies pioneer the existence of a novel programmed cell death pathway in malaria parasite plasmodium and suggest that it could be helpful in developing new targeted anti-malarial therapies. Considering this fact, we evaluated the underlying action mechanism of this pathway in mefloquine (MQ) treated parasite. Since cysteine proteases play a key role in apoptosis hence we performed preliminary computational simulations to determine binding affinity of MQ with metacaspase protein model. Binding pocket identified using computational studies, was docked with MQ to identify it's potential to bind with the predicted protein model. We further determined apoptotic markers such as mitochondrial dysregulation, activation of cysteine proteases and in situ DNA fragmentation in MQ treated/untreated parasites by cell based assay. Our results showed low mitochondrial membrane potential, enhanced activity of cysteine protease and increased number of fragmented DNA in treated parasites compared to untreated ones. We next tested the involvement of oxidative stress in MQ mediated cell death and found significant increase in reactive oxygen species generation after 24 h of treatment. Therefore we conclude that apart from hemozoin inhibition, MQ is competent to induce apoptosis in plasmodium by activating metacaspase and ROS production.
