ABSTRACT
BACKGROUND: Novel, in silico-designed anticancer compounds were synthesized in our laboratory namely, 2-ethyl-3-O-sulphamoyl-estra-1,3,5(10),15-tetraen-17-ol (ESE-15-ol) and 2-ethyl-3-O-sulphamoyl-estra-1,3,5(10)16-tetraene (ESE-16). These compounds were designed to have improved bioavailability when compared to their source compound, 2-methoxyestradiol. This theoretically would be due to their increased binding affinity to carbonic anhydrase II, present in erythrocytes. Since the novel compounds under investigation are proposed to be transported within erythrocytes bound to carbonic anhydrase II, the morphological effect which they may exert on whole blood and erythrocytes is of great significance. A secondary outcome included revision of previously reported procedures for the handling of the whole blood sample. The purpose of this study was twofold. Firstly, the ultrastructural morphology of a healthy female's erythrocytes was examined via scanning electron microscopy (SEM) after exposure to the newly in silico-designed compounds. Morphology of erythrocytes following exposure to ESE-15-ol and ESE-16 for 3 minutes and 24 hours at 22°C were described with the use of SEM. The haemolytic activity of the compounds after 24 hours exposure were also determined with the ex vivo haemolysis assay. Secondly, storage conditions of the whole blood sample were investigated by determining morphological changes after a 24 hour storage period at 22°C and 37°C. RESULTS: No significant morphological changes were observed in the erythrocyte morphology after exposure to the novel anticancer compounds. Storage of the whole blood samples at 37°C for 24 hours resulted in visible morphological stress in the erythrocytes. Erythrocytes incubated at 22°C for 24 hours showed no structural deformity or distress. CONCLUSIONS: From this research the optimal temperature for ex vivo exposure of whole blood samples to ESE-15-ol and ESE-16 for 24 hours was determined to be 22°C. Data from this study revealed the potential of these compounds to be applied to ex vivo study techniques, since no damage occurred to erythrocytes ultrastructure under these conditions. As no structural changes were observed in erythrocytes exposed to ESE-15-ol and ESE-16, further ex vivo experiments will be conducted into the potential effects of these compounds on whole blood. Optimal incubation conditions up to 24 hours for whole blood were established as a secondary outcome.
Subject(s)
Humans , Female , Middle Aged , Sulfonamides/pharmacology , Computer Simulation , Carbonic Anhydrase Inhibitors/pharmacology , Erythrocytes/drug effects , Estradiol/analogs & derivatives , Estrenes/pharmacology , Antineoplastic Agents/pharmacology , Sulfonamides/toxicity , Sulfonamides/pharmacokinetics , Temperature , Carbonic Anhydrase Inhibitors/pharmacokinetics , Biological Availability , Microscopy, Electron, Scanning , Carrier Proteins/pharmacology , Carrier Proteins/pharmacokinetics , Carbonic Anhydrase II/drug effects , Qualitative Research , Erythrocytes/ultrastructure , Estradiol/toxicity , Estradiol/pharmacology , Estradiol/pharmacokinetics , Estrenes/pharmacokinetics , Drug Discovery , Hemolysis/drug effects , Antineoplastic Agents/pharmacokineticsABSTRACT
2-Methoxyestradiol-bis-sulphamate is a bis-sulphamoylated derivative of the naturally occurring 17-beta-estradiol metabolite namely 2-methoxyestradiol. 2-Methoxyestradiol-bis-sulphamate is regarded as a potential anticancer drug with increased antiproliferative activity when compared to 2-methoxyestradiol. The aim of this pilot in vitro study was to determine the influence of 2-methoxyestradiol-bis-sulphamate on cell growth, morphology and possible induction of certain types of cell death in the SNO esophageal carcinoma cell line. A dose-dependent study (0.2-1.0 microM) was conducted with an exposure time of 24 hours. Data revealed that 2-methoxyestradiol-bis-sulphamate reduced cell numbers statistically significantly to 74% after exposure to 0.4 microM of the drug. Morphological studies including light microscopy demonstrated hallmarks of apoptosis, while fluorescent microscopy revealed both the presence of apoptosis and autophagy as types of cell death being induced in SNO cells after 24 hours of exposure to 0.4 microM 2-methoxyestradiol-bis-sulphamate.
Subject(s)
Humans , Apoptosis , Autophagy , Cell Count , Carcinoma, Squamous Cell/pathology , Cell Cycle , Cell Division , Cell Line, Tumor , Dose-Response Relationship, Drug , Estriol/analogs & derivatives , Estriol/pharmacology , Esophageal Neoplasms/pathologyABSTRACT
In the search for new and improved anticancer therapies, researchers have identified several potentially useful compounds. One of these agents is 2-methoxyestradiol-bis-sulphamate (2ME-BM), a sulphamoylated derivative of 2-methoxyestradiol. The objective of this study was to evaluate 2ME-BM's in vitro efficacy as antiproliferative agent in the MCF-7 breast adenocarcinoma cell line. Light- and fluorescent microscopy showed decreased cell density, increased apoptotic characteristics and significant ultrastructural aberrations indicative of autophagic cell death after 24 hours of exposure at a concentration of 0.4 microM. In addition, mitotic indices revealed that 2ME-BM induces a G2M block. The latter was confirmed by flow cytometric analyses where increased sub-G1 and G2/M fractions, as well as an increase in cycli n B1 levels were observed. Further in vitro research into the mechanism of this potentially useful anticancer compound is thus warranted.
Subject(s)
Humans , Female , Cell Cycle , Estriol/analogs & derivatives , Estriol/pharmacology , Estriol/chemistry , Cell Line, Tumor , Cell Line, Tumor/ultrastructure , Cell Proliferation , Breast Neoplasms , Molecular StructureABSTRACT
C2- and C4-position 17beta-estradiol metabolites play an important role in breast carcinogenesis. 2-Hydroxyestradiol and 4-hydroxyestradiol are implicated in tumorigenesis via two pathways. These pathways entail increased cell proliferation and the formation of reactive oxygen species that trigger an increase in the likelihood of deoxyribonucleic acid mutations. 2-Methoxyestradiol, a 17beta-estradiol metabolite, however, causes induction of apoptosis in transformed and tumor cells; thus exhibiting an antiproliferative effect on tumor growth. The 4-hydroxyestradiol:2-methoxyestradiol and 2-hydroxyestradiol:2-methoxyestradiol ratios therefore ought to be taken into account as possible indicators of carcinogenesis.
Subject(s)
Humans , Animals , Estradiol/analogs & derivatives , Estradiol/metabolism , Breast Neoplasms/metabolism , Cell ProliferationABSTRACT
Proteins of the B-cell lymphoma 2 family are crucial for the regulation of apoptosis. B-cell lymphoma 2-associated X is a pro-apoptotic protein, while B-cell lymphoma 2 protein opposes apoptosis. The influence of 1 microM 2-methoxyestradiol was investigated on the expression levels of these two proteins in MCF-7 cells. 2-Methoxyestradiol exposure did not influence B-cell lymphoma 2 protein expression levels after 24 h of exposure. In contrast, B-cell lymphoma 2-associated X protein levels were significantly reduced. An improved differential interference contrasting technique revealed compromised cell density and the presence of a mitotic block in exposed cells. The study proposes that the influence of 2-methoxyestradiol on the expression of these proteins may be time- and cell type dependent and thus not evident d uring the mitotic block observed. Investigation of the regulation of the B-cell lymphoma 2 family will allow researchers to consider signaling pathways for diseases where apoptosis can potentially be controlled.