Selective Killing of Melanoma Cells With Plasma and p-FAK-GNP

Objectives: Melanomas are fast growing high-mortality tumors, and specific treatments for melanomas are needed. Melanoma cells overexpress focal adhesion kinase (FAK) compared to normal keratinocytes, and we sought to exploit this difference to create a selectively lethal therapy.


Methods: The G361 and HaCaT cells were cultured in RPMI 1640 media and DMEM supplemented with 25 mM Hepes, 100 μg/mL penicillin/streptomycin, 4 mM L-glutamine, and 10 % fetal bovine serum. Cultures were maintained at 37 °C in a 5 % CO₂ atmosphere in a humidified incubator.
For the treatment of G361 or HaCaT cells (4 × 104 cells) with plasma, the cells were seeded on the glass cover slips (12 mm diameter). The distance between cells and the device was kept at 2 mm during the 30 s treatment. For the 24 h before the treatment, cells were incubated in growth media with or without p-FAK-GNPs. Just before the treatment, the cover glasses were washed with PBS to remove non-selectively bound and unbound p-FAK-GNP conjugates.
Results: Treatment with p-FAK-GNP decreased the viability of G361 cells in a time dependent manner by inducing apoptosis. To maximize the preferential killing of G361 cells, non-thermal atmospheric pressure plasma was used to stimulate the GNP within p-FAK-GNP. Combined treatment with plasma and p-FAK-GNP showed much higher lethality against G361 cells than HaCaT keratinocyte cells. The p-FAK-GNP induced apoptosis over 48 hours in G361 cells, whereas plasma and p-FAK-GNP killed G361 cells immediately.

Conclusions: This study demonstrates that combining plasma with p-FAK-GNP results in selective lethality against human melanoma cells.