Iodine loaded nanoparticles with commercial applicability increase survival in mice cancer models with low degree of side effects

Background: The recorded use of iodine in medicine, dates to 5000 BC. Molecular iodine (I₂ ) has been claimed to exert an antineoplastic effect that triggers apoptotic and re-differentiation mechanisms in different types of cancer cells in animal studies. Hitherto, all experiments published have been carried out with I₂ diluted in water preparations resulting in the administration of ionized iodide, either alone or in combination with low levels of I₂ . To maximize the levels of I₂ by avoiding water solutions we have managed to develop a colloidal nano particle (NP) loaded with I₂ with a Z-average of 7-23 nm with remarkable stability, preferable osmolality and commercial applicability.

Aims: Here we report the results from formulation and pre-clinical studies with the rationale: a) to find a tolerable dose of the I₂ NP system delivered intravenously or per-orally, and b) to determine if the tolerable doses are efficacious in murine models of cancer.

Methods and results: A novel drug delivery system with I₂ NP was formulated and murine cancer models with CT26, MDA-MB-231 and LL/2 cells were used to analyse the efficacy. Despite the formulation challenges we were successful in constructing stable NPs loaded with I₂ which have convincing commercial applicability. We conclude that administration of the NP I₂ drug delivery system: 1. Blunted tumour growth in a xenograft breast cancer model; 2. Had a significant effect on survival in the orthotopic, syngeneic lung metastasis model; 3. Showed reduced tumour burden in post-mortem evaluation and; 4. Was associated with low degree of side effects.

Conclusions: Taken all together, our findings indicate that the NP I₂ drug delivery system may serve as a novel effective cancer treatment with low degree of side effects. This is something which needs further exploration including confirmation in future clinical trials.