Bioelectric theory of cancer (Levin)

The claim. Resting membrane potential and the bioelectric networks that cells form through gap junctions are an instructive layer of control above genetics: they store and communicate information about tissue pattern, and cells that fall out of the pattern behave as individuals rather than as parts of an organ. Tumour cells are chronically depolarised relative to their normal counterparts, a fact known since the 1970s. Levin's hypothesis is that depolarisation is not merely a marker but a cause, that a depolarised region can recruit distant cells into tumour-like behaviour, and that re-establishing normal voltage can normalise cells despite oncogenic mutations. Ion channels and pumps are therefore therapeutic targets for pattern control.

Who and when. Clarence Cone measured depolarisation in tumour cells and proposed a role in proliferation in the 1970s. Michael Levin's laboratory at Tufts developed the modern theory from work on regeneration and left-right patterning. Chernet and Levin (2013) showed in Xenopus tadpoles that transmembrane potential detects and controls tumour development; Chernet, Adams, Lobikin and Levin (Oncotarget 2016) used optogenetics, expressing light-gated channels and pumps that hyperpolarise cells, to lower the incidence of KRAS-induced tumour-like structures and to increase the frequency with which established ones regressed. Levin's 2021 Cell review set bioelectric signalling alongside embryogenesis and regeneration.

Evidence for. Depolarisation is consistent across tumour types. In tadpoles, depolarising cells at a distance from a melanocyte population converts those melanocytes to an invasive, metastatic-like phenotype, and hyperpolarising channels suppress oncogene-induced tumours; both effects are transmitted through the tissue rather than the mutated cell alone. Voltage-gated potassium channels such as Kv10.1 (EAG1) are overexpressed in many cancers and correlate with prognosis. Gap junction loss is common in tumours. Cancer neuroscience has shown that gliomas form electrical and synaptic connections with neurons and that this activity drives their growth (Venkatesh 2019; Venkataramani 2019), which is a related, mainstream demonstration that electrical signalling matters.

Evidence against and limits. Almost all of the direct evidence is from amphibian embryos and tadpoles; the KRAS structures studied are tumour-like, not proven cancers. No human trial has tested bioelectric normalisation, and epidemiological signals from ion channel drugs are inconsistent. The route from voltage to gene expression is understood only in part (calcium, serotonin and butyrate transport have been implicated). Tumour treating fields, an approved alternating-field device for glioblastoma, acts on mitosis and is not a test of this theory.

Predictions that held or failed. Held so far: depolarisation induces, and hyperpolarisation suppresses, tumour-like growth in animal models; the effect is non-cell-autonomous. Untested: whether ion channel modulation can treat or prevent human cancer; whether bioelectric states can be read as a biomarker in patients.

Therapies that came from it. None established. Repurposing of approved ion channel drugs and the design of optogenetic or pharmacological 'electroceuticals' are proposed. Cancer neuroscience trials of anti-seizure drugs in glioma are adjacent. The theory is a tissue-level account in the tradition of the tissue organisation field theory, and it claims, like the epigenetic view, that cell state can override mutation.

Status: contested. A newer proposal with reproducible results in one model organism and a plausible mechanism, awaiting evidence in mammals and in people.