Exploring the Interplay Between Hyperthermia and Cytotoxic Drugs in Ocular Melanoma Cell Lines: Implications and Variability in Treatment Efficiency.

Purpose: Uveal and conjunctival melanomas are rare ocular malignancies that present significant diagnostic and therapeutic challenges. This study investigates the efficacy of combining hyperthermic treatments with chemotherapeutics, such as cisplatin, docetaxel, and mitoxantrone, to develop more effective therapies for specific melanoma subtypes, aiming to overcome the limitations of traditional approaches. Methods: The study used hyperthermia by exposing melanoma cell lines to temperatures of 42°C, 45°C, and 47°C for 1 hour. Alongside hyperthermia, cytotoxic drugs were applied at different concentrations to assess their combined effects on cell proliferation and viability. Expression of heat shock proteins was evaluated by immunocytochemistry stainings and Western blots. Results: Findings reveal that certain melanoma cell lines exhibited increased proliferation at 42°C without a significant decrease in cell confluence. Conversely, temperatures of 45°C and above significantly impaired cell viability. Comparative statistical analysis suggests synergistic effects when combining mild to elevated hyperthermia with cisplatin and mitoxantrone, and to some extent with docetaxel. Conclusions: This study serves as preliminary work for the inclusion of superparamagnetic iron oxide nanoparticles functionalized with cytotoxic drugs, which may present a promising therapeutic strategy for treating ocular melanomas. Although further research is necessary, this approach has the potential to significantly advance the treatment landscape for these ocular malignancies, offering a targeted, effective, and minimally invasive option for patients.