Anti-tumor effect of sodium-induced thermochemical ablation therapy.

PURPOSE: We have recently proposed utilizing alkali metal as powerful self heating seeds to thermally ablate tumor tissues. This study is dedicated to disclosing some fundamental mechanisms related to the anti-tumor effects of sodium and its controllability as an economic, safe and efficient thermochemical agent in targeted tumor treatment.

MATERIALS AND

METHODS

EMT6 cell line was incubated under four situations: no treatment, NaOH solution treatment, hyperthermia treatment and a combined NaOH solution and hyperthermia treatment. Cell cytotoxicity was measured by a CASY cell counter and analyzer system. Breast EMT6 tumors in mice were subjected to treatment by NaOH solution, hyperthermia and encapsulated sodium. The changes of tumor volumes were continuously measured for 12 days after treatment. Tumors of another four mice were harvested immediately after treatment to assess viability.

RESULTS

In vitro cell experiments suggested that thermal effect combined with chemical treatment produced a more significant cell cytotoxicity compared to thermal or chemical treatment alone. Encapsulated sodium demonstrated a slower and more continuous heat release than bare sodium. The sodium treatment produced a dramatic regression of tumors that lasted throughout the 12 days of the study. Histological sections showed complete necrosis in sodium-treated tumors, whereas control tumors and heat-treated tumors remained viable, and NaOH-treated tumors showed partial destruction.

CONCLUSIONS

The results suggest that sodium allows a minimally invasive treatment which could produce both thermal and chemical lethal injury to tumors. Using sodium to ablate target tumors is potentially an effective, safe and low cost way to treat malignant tumors.