Melanoma is one type of skin cancer that develops from melanocytes and has been reported as the cause of deaths in different continents globally. This study aims to selectively “kill” only skin cancer cells by applying a customer designed and portable atmospheric pressure plasma jet (APPJ). Human melanoma (A375) and Lewis lung carcinoma (LLC) were selected as the target cancer cells to compare with the effects of APPJ toward L-929 mouse fibroblasts. The impacts of APPJ treatments on the cell viability and morphology of three types of cells were evaluated quantitatively by LDH and MTT assays whereas the qualitative cell behavior was provided by cell morphological changes. Importantly, the mechanism of evolution in cell fate resulted from APPJ treatments for the three types of cells was elucidated by cell apoptosis integrated with caspase-9 activities, which determined the threshold of APPJ treatment time toward individual cell type. Furthermore, it was found that the cell culture time assisted benign cells (L-929 fibroblasts) to resume proliferation activities from the impact of APPJ treatment. Therefore, the selective impacts on tumor and benign cells demonstrated in this study shed lights of APPJ treatments for the future developments of direct plasma skin cancer therapy.

黑色素瘤是一种由黑色素细胞发展而来的皮肤癌，据报道是全球不同大陆的死亡原因。这项研究旨在通过应用客户设计的便携式大气压等离子体射流 (APPJ) 来选择性地“杀死”皮肤癌细胞。选择人类黑色素瘤 (A375) 和 Lewis 肺癌 (LLC) 作为靶癌细胞，以比较 APPJ 对 L-929 小鼠成纤维细胞的影响。通过 LDH 和 MTT 测定定量评估 APPJ 处理对三种类型细胞的细胞活力和形态的影响，而定性细胞行为由细胞形态变化提供。重要的，通过与 caspase-9 活性相结合的细胞凋亡阐明了 APPJ 处理三种类型细胞导致的细胞命运进化机制，这决定了 APPJ 处理时间对单个细胞类型的阈值。此外，发现细胞培养时间有助于良性细胞（L-929 成纤维细胞）从 APPJ 治疗的影响中恢复增殖活动。因此，本研究中证明的对肿瘤和良性细胞的选择性影响为 APPJ 治疗为直接血浆皮肤癌治疗的未来发展提供了启示。