In vivo efficacy of nano hyaluronan-conjugated cisplatin for treatment of murine melanoma.

BACKGROUND: Melanoma is a deadly skin cancer with rapidly rising incidence. While localized melanoma can be treated with excision, there are at present no similarly effective treatments for regional and distant disease, so survival rates are low. One problem is that melanoma is chemo-resistant, and most chemotherapy doses are limited by systemic toxicity. A method for delivering high-dose chemotherapy directly to tumors and draining lymph nodes could have the advantage of allowing much higher effective doses with reduced systemic exposure.
METHODS: Human melanoma cell line A-2058 tumor cells were injected into athymic mice. After tumors grew to 50~100 mm³ mice were divided into five groups: (1) nontreated (2) intravenous (i.v.) cisplatin, (3) i.v. nano hyaluronan-conjugated cisplatin (HA-Pt), (4) subcutaneous (s.c.) peri-tumoral cisplatin, and (5) s.c. peri-tumoral HA-Pt. All treatment groups received 3 weekly doses of 10 mg/kg.
RESULTS: Tumors grew progressively in all control, i.v. cisplatin, and s.c. cisplatin groups. Tumors showed a trend toward slower growth in the i.v. HA-Pt group, but all animals died or were euthanized per protocol within 3 weeks of treatment. Tumors showed shrinkage only in the subcutaneous peri-tumoral HA-cisplatin group; one of these mice appeared to be cured.
CONCLUSIONS: Peri-tumoral HA-cisplatin may be shown potential as a therapeutic option in treatment of certain types of melanoma.