title: In vitro ultrastructural changes of MCF-7 for metastasise bone cancer and induction of apoptosis via mitochondrial cytochrome C released by CaCO3/Dox nanocrystals.
abstract: Bones are the most frequent site for breast cancer cells to settle and spread (metastasise); bone metastasis is considered to have a substantial impact on the quality of patients with common cancers. However, majority of breast cancers develop insensitivity to conventional chemotherapy which provides only palliation and can induce systemic side effects. In this study we evaluated the effect of free Dox and CaCO3/Dox nanocrystal on MCF-7 breast cancer using MTT (3-[4, 5-dimethylthiazol-2-yl]-2, 5-diphenyl tetrazolium bromide), neural red, and lactate dehydrogenase colorimetric assays while DNA fragmentation and BrdU genotoxicity were also examined. Apoptogenic protein Bax, cytochrome C, and caspase-3 protein were analysed. Morphological changes of MCF-7 were determined using contrast light microscope and scanning and transmission electron microscope (SEM and TEM). The findings of the analysis revealed higher toxicity of CaCO3/Dox nanocrystal and effective cells killing compared to free Dox, morphological changes such as formation of apoptotic bodies, membrane blebbing, and absent of microvilli as indicated by the SEM analysis while TEM revealed the presence of chromatin condensation, chromosomal DNA fragmentation, cell shrinkage, and nuclear fragmentation. Results of TUNEL assay verified that most of the cells undergoes apoptosis by internucleosomal fragmentation of genomic DNA whereas the extent of apoptotic cells was calculated using the apoptotic index (AI). Therefore, the biobased calcium carbonate nanocrystals such as Dox carriers may serve as an alternative to conventional delivery system.
authors.affiliation: Laboratory of Molecular Biomedicine, Institute of Bioscience, Universiti Putra Malaysia (UPM), 43400 Serdang, Malaysia.
authors.forename: Abdullahi Shafiu
authors.initials: AS
authors.lastname: Kamba
authors.affiliation: Laboratory of Molecular Biomedicine, Institute of Bioscience, Universiti Putra Malaysia (UPM), 43400 Serdang, Malaysia.
authors.forename: Maznah
authors.initials: M
authors.lastname: Ismail
authors.affiliation: Faculty of Veterinary Medicine, Universiti Putra Malaysia (UPM), 43400 Serdang, Malaysia.
authors.forename: Tengku Azmi Tengku
authors.initials: TA
authors.lastname: Ibrahim
authors.affiliation: Laboratory of Molecular Biomedicine, Institute of Bioscience, Universiti Putra Malaysia (UPM), 43400 Serdang, Malaysia ; Faculty of Veterinary Medicine, Universiti Putra Malaysia (UPM), 43400 Serdang, Malaysia.
authors.forename: Zuki Abu Bakar
authors.initials: ZA
authors.lastname: Zakaria
authors.affiliation: Department of Pure and Applied Chemistry, Usmanu Danfodiyo University, PMB, Sokoto 2346, Nigeria.
authors.forename: Lawal Hassan
authors.initials: LH
authors.lastname: Gusau
mesh_terms: D000863:Antacids / Q000494:pharmacology*; D000903:Antibiotics, Antineoplastic / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects*; D001859:Bone Neoplasms / Q000188:drug therapy / Q000201:enzymology / Q000556:secondary / Q000648:ultrastructure; D001943:Breast Neoplasms / Q000188:drug therapy / Q000201:enzymology / Q000648:ultrastructure; D002119:Calcium Carbonate / Q000494:pharmacology*; D045744:Cell Line, Tumor; D045304:Cytochromes c / Q000378:metabolism*; D004317:Doxorubicin / Q000494:pharmacology*; D016503:Drug Delivery Systems; D005260:Female; D006801:Humans; D024101:Mitochondrial Proteins / Q000378:metabolism*; D053758:Nanoparticles; D009362:Neoplasm Metastasis; D009363:Neoplasm Proteins / Q000378:metabolism*
chemical_list: D000863:Antacids; D000903:Antibiotics, Antineoplastic; D024101:Mitochondrial Proteins; D009363:Neoplasm Proteins; D004317:Doxorubicin; D045304:Cytochromes c; D002119:Calcium Carbonate