Related Experiment Video
Updated: Apr 15, 2026
Simultaneous Electrophysiological Recording and Calcium Imaging of Suprachiasmatic Nucleus Neurons
Published on: December 8, 2013
Melatonin affects voltage-dependent calcium and potassium currents in MCF-7 cell line cultured either in growth or
Roberta Squecco1, Alessia Tani2, Sandra Zecchi-Orlandini1
1Department of Experimental and Clinical Medicine, Section of Physiological Sciences, University of Florence, 50134 Florence, Italy.
Abstract:
Big efforts have been dedicated up to now to identify novel targets for cancer treatment. The peculiar biophysical profile and the atypical ionic channels activity shown by diverse types of human cancers suggest that ion channels may be possible targets in cancer therapy. Earlier studies have shown that melatonin exerts an oncostatic action on different tumors. In particular, it was shown that melatonin was able to inhibit growth/viability and proliferation, to reduce the invasiveness and metastatic properties of human estrogen-sensitive breast adenocarcinoma MCF-7 cell line cultured in growth medium, with substantial impairments of epidermal growth factor (EGF) and Notch-1-mediated signaling. The purpose of this work was to evaluate on MCF-7 cells the possible effects of melatonin on the biophysical features known to have a role in proliferation and differentiation, by using the patch-clamp technique. Our results show that in cells cultured in growth as well as in differentiation medium melatonin caused a hyperpolarization of resting membrane potential paralleled by significant changes of the inward Ca(2+) currents (T- and L-type), outward delayed rectifier K(+) currents and cell capacitance. All these effects are involved in MCF-7 growth and differentiation. These findings strongly suggest that melatonin, acting as a modulator of different voltage-dependent ion channels, might be considered a new promising tool for specifically disrupting cell viability and differentiation pathways in tumour cells with possible beneficial effects on cancer therapy.
Insights
Melatonin influences cancer cell ion channel activity, altering membrane potential and ion currents. This suggests melatonin as a potential therapeutic agent for cancer by disrupting tumor cell viability and differentiation.
Area of Science:
- Oncology
- Cell Biology
- Biophysics
Background:
- Ion channels are potential therapeutic targets in cancer due to altered activity in tumors.
- Melatonin exhibits oncostatic effects, inhibiting growth and reducing invasiveness in cancer cells.
- Previous studies show melatonin impairs growth factor signaling in breast cancer cells.
Purpose of the Study:
- To investigate melatonin's effects on biophysical properties crucial for proliferation and differentiation in MCF-7 breast cancer cells.
- To assess melatonin's impact on ion channel activity and membrane potential using electrophysiological techniques.
Main Methods:
- Utilized the patch-clamp technique to measure ion channel currents and membrane potential.
- Cultured human estrogen-sensitive breast adenocarcinoma MCF-7 cells in both growth and differentiation media.
- Analyzed changes in resting membrane potential, calcium (T- and L-type) and potassium currents, and cell capacitance.
Main Results:
- Melatonin induced hyperpolarization of the resting membrane potential in MCF-7 cells.
- Observed significant alterations in inward Ca(2+) currents (T- and L-type) and outward delayed rectifier K(+) currents.
- Reported changes in cell capacitance, indicating effects on cell volume and membrane dynamics.
Conclusions:
- Melatonin modulates voltage-dependent ion channels, impacting key cellular processes in breast cancer.
- These findings support melatonin as a potential therapeutic agent for cancer by disrupting tumor cell viability and differentiation pathways.
- Melatonin's ability to alter ion channel function offers a novel approach for targeted cancer therapy.
Related Concept Videos
01:26Voltage-gated Ion Channels
Generally, all voltage-gated ion channels have a 'voltage-sensing domain' that spans the lipid bilayer. The charged residues in the sensor move in response to the membrane potential changes that open the channel allowing ions movement. There are several types of...
01:26Voltage-gated Ion Channels
01:24Resting Membrane Potential
The Inside of a Neuron is More Negative
The membrane potential of a cell can be measured by inserting a microelectrode into a cell and comparing the charge to a reference electrode in the extracellular fluid. The...
01:21The Resting Membrane Potential
01:19The Role of Ion Channels in Neuronal Computation
Sometimes a single EPSP is strong enough to induce an action potential in the postsynaptic neuron. However, multiple presynaptic inputs must often create EPSPs around the same time for the postsynaptic neuron to be sufficiently depolarized to fire an action potential....
01:27Feedback Regulation of Calcium Concentration
Various transmembrane receptors, such as G protein-coupled receptors (GPCRs), elicit a response to extracellular signals by increasing cytosolic calcium. Activated GPCRs...