Ca2+-induced changes in energy metabolism and viability of melanoma cells

Cancer cells are characterized by a high rate of glycolysis, which is their primary energy source. We show here that a rise in intracellular-free calcium ion (Ca2+), induced by Ca2+-ionophore A23187, exerted a deleterious effect on glycolysis and viability of B16 melanoma cells. Ca2+-ionophore caused a dose-dependent detachment of phosphofructokinase (EC 2.7.1.11), one of the key enzymes of glycolysis, from cytoskeleton. It also induced a decrease in the levels of glucose 1,6-bisphosphate and fructose 1,6-bisphosphate, the two stimulatory signal molecules of glycolysis. All these changes occurred at lower concentrations of the drug than those required to induce a reduction in viability of melanoma cells. We also found that low concentrations of Ca2+-ionophore induced an increase in adenosine 5′-triphosphate (ATP), which most probably resulted from the increase in mitochondrial-bound hexokinase, which reflects a defence mechanism. This mechanism can no longer operate at high concentrations of the Ca2+-ionophore, which causes a decrease in mitochondrial and cytosolic hexokinase, leading to a drastic fall in ATP and melanoma cell death. The present results suggest that drugs which are capable of inducing accumulation of intracellular-free Ca2+ in melanoma cells would cause a reduction in energy-producing systems, leading to melanoma cell death. © 1999 Cancer Research Campaig

Human matrix metalloproteinases: An ubiquitarian class of enzymes involved in several pathological processes

Human matrix metalloproteinases (MMPs) belong to the M10 family of the MA clan of endopeptidases. They are ubiquitarian enzymes, structurally characterized by an active site where a Zn(2+) atom, coordinated by three histidines, plays the catalytic role, assisted by a glutamic acid as a general base. Various MMPs display different domain composition, which is very important for macromolecular substrates recognition. Substrate specificity is very different among MMPs, being often associated to their cellular compartmentalization and/or cellular type where they are expressed. An extensive review of the different MMPs structural and functional features is integrated with their pathological role in several types of diseases, spanning from cancer to cardiovascular diseases and to neurodegeneration. It emerges a very complex and crucial role played by these enzymes in many physiological and pathological processes

Clotrimazole Preferentially Inhibits Human Breast Cancer Cell Proliferation, Viability and Glycolysis

BACKGROUND: Clotrimazole is an azole derivative with promising anti-cancer effects. This drug interferes with the activity of glycolytic enzymes altering their cellular distribution and inhibiting their activities. The aim of the present study was to analyze the effects of clotrimazole on the growth pattern of breast cancer cells correlating with their metabolic profiles. METHODOLOGY/PRINCIPAL FINDINGS: Three cell lines derived from human breast tissue (MCF10A, MCF-7 and MDA-MB-231) that present increasingly aggressive profiles were used. Clotrimazole induces a dose-dependent decrease in glucose uptake in all three cell lines, with K(i) values of 114.3±11.7, 77.1±7.8 and 37.8±4.2 µM for MCF10A, MCF-7 and MDA-MB-231, respectively. Furthermore, the drug also decreases intracellular ATP content and inhibits the major glycolytic enzymes, hexokinase, phosphofructokinase-1 and pyruvate kinase, especially in the highly metastatic cell line, MDA-MB-231. In this last cell lineage, clotrimazole attenuates the robust migratory response, an effect that is progressively attenuated in MCF-7 and MCF10A, respectively. Moreover, clotrimazole reduces the viability of breast cancer cells, which is more pronounced on MDA-MB-231. CONCLUSIONS/SIGNIFICANCE: Clotrimazole presents deleterious effects on two human breast cancer cell lines metabolism, growth and migration, where the most aggressive cell line is more affected by the drug. Moreover, clotrimazole presents little or no effect on a non-tumor human breast cell line. These results suggest, at least for these three cell lines studied, that the more aggressive the cell is the more effective clotrimazole is

Mobile-phone-based e-diary derived patient reported outcomes: Association with clinical disease activity, psychological status and quality of life of patients with multiple sclerosis.

BackgroundThe applicability of mobile digital technology to promote clinical care of people with multiple sclerosis (pwMS) is gaining increased interest as part of the implementation of patient-centered approaches. We aimed at assessing adherence to a smartphone-based e-diary, which was designed to collect patient-reported outcomes (PROs). Secondary objectives were to evaluate the construct and predictive validity of e-diary derived PROs and to explore the various factors that were associated with changes in PROs over time.Materials and methodsIn this observational cohort study patients downloaded an MS tailored e-diary into their personal smartphones. Report of PROs was enquired once monthly for a period of one year through a smartphone-based application, using previously validated tools. An e-diary derived bodily function summary score (eBF) was defined as the sum of scores depicting vision, limbs function, pain, bowl/ bladder dysfunction, pseudobulbar affect and spasticity. Multiple linear regression and analysis of covariance were used to determine the association between PROs, clinician-reported outcomes (ClinROs) of disease activity and quality of life (QoL). Regression coefficient analysis was used to compare the slope of change in eBF before and after a relapse.Results97 pwMS downloaded the e-diary [Female: 64 (66%), EDSS 3.4±2.1]. 76 patients (78%) completed the 12-month study period. 53 patients (55%) submitted ≥75% of requested surveys. Anxiety was negatively associated with adherence to periodic PROs assessments by the e-diary. E-diary derived PROs were significantly correlated with corresponding functional system scores (0.38ConclusionAdherence of pwMS to recording in an e-diary collecting PROs was high. Changes in e-diary derived PROs over time predict clinical MS relapses on the group level and thus carry the potential of usage in clinical research as well as for improved MS care in real world setting