Vm/CMP Cancer Research Results

Membrane potential is the voltage difference between the inside and outside of a cell membrane.
𝑉𝑚=𝑉𝑖𝑛𝑠𝑖𝑑𝑒−𝑉𝑜𝑢𝑡𝑠𝑖𝑑𝑒
The outside of the cell is normally defined as 0 mV reference.
Therefore most cells have a negative internal voltage.

| Cell type        | Resting membrane potential        |
| ---------------- | --------------------------------- |
| Neurons          | −60 to −70 mV                     |
| Muscle cells     | −80 to −90 mV                     |
| Epithelial cells | −30 to −50 mV                     |
| Cancer cells     | −10 to −40 mV (often depolarized) |


Cancer cells are usually less negative than normal cells.
This depolarization correlates with proliferation and metastasis.
Depolarization of the membrane potential (Vm) means 
the membrane potential becomes less negative (more positive).

The cell membrane behaves like:
-capacitor (lipid bilayer)
-resistors (ion channels)

Membrane capacitance:

𝐶𝑚≈1 𝜇𝐹/𝑐𝑚2	
Cell diameter	Area	   At 1.0 µF/cm²	At 1.9 µF/cm²
10 µm	    3.14×10−6cm²	3.1 pF	        6.0 pF
15 µm	    7.07×10−6cm²	7.1 pF	       13.4 pF
20 µm	    1.26×10−5cm²	12.6 pF	       23.9 pF

Magnetic fields can transiently increase VGSC/VGCC activity, but that does not necessarily promote cancer because:
-the activation is temporary
-the perturbation may destabilize cancer cell ion homeostasis.