Alfei Silvana, Torazza Carola, Bacchetti Francesca, Signorello Maria Grazia, Passalacqua Mario, Domenicotti Cinzia, Marengo Barbara
Department of Pharmacy, University of Genoa, Viale Cembrano, 16148 Genoa, Italy.
Biochemistry Laboratory, Department of Pharmacy, University of Genoa, Viale Benedetto XV 3, 16132 Genova, Italy.
Int J Mol Sci. 2025 Mar 30;26(7):3227. doi: 10.3390/ijms26073227.
Cutaneous metastatic melanoma (CMM) is the most aggressive form of skin cancer, with characteristics including a poor prognosis, chemotherapy-induced secondary tumorigenesis, and the emergence of drug resistance. Our recent study demonstrated that triphenyl phosphonium (TPP)-based nanovesicles (BPPB), which have amphiphilic properties, exert potent ROS-dependent anticancer effect against PLX4032 (PLX)-sensitive MeOV BRAF and MeTRAV BRAF mutant cell lines, evidencing more marked efficacy on MeOV cells. Here, taking advantage of this in vitro model, the antitumoral effect of BPPB was tested on PLX-resistant (PLX-R) MeOV BRAF and MeTRAV BRAF mutant cell lines to find a new potential strategy to fight melanoma therapy resistance. Specifically, we investigated both its effects on cell viability in dose- and time-dependent experiments and those on ROS generation. Our results show that BPPB exerted strong antiproliferative effects, regardless of their acquired resistance of cells to PLX, that correlated with ROS overproduction for 24 h treatments only. Moreover, in terms of cell viability, PLX-R MeTRAV cells demonstrated a remarkably higher tolerance to 24 h BPPB treatment than PLX-R MeOV. On the contrary, BPPB exposure for longer periods induced similar responses in both cell lines (IC = 87.8-106.5 nM on MeOV and 81.0-140.6 nM on MeTRAV). Notably, BPPB cytotoxicity on non-tumorigenic human keratinocytes (HaCaT) was low, thus establishing that BPPB is appreciably selective for CMM cells, allowing for selectivity index values (SIs) up to 11.58. Furthermore, the BPPB concentration causing 50% hemolysis (HC) was found to be 16-173 and 4-192-fold higher than the IC calculated for PLX-R MeOV and MeTRAV cells, respectively. Correlation studies established that BPPB exerts cytotoxic effects on PLX-R MeOV and MeTRAV cells by a time-dependent mechanism, while a concentration-dependent mechanism was observed only at 24 h of exposure. Finally, a ROS-dependent mechanism can be assumed only in PLX-R MeTRAV cells in 72 h treatment.
皮肤转移性黑色素瘤（CMM）是皮肤癌中最具侵袭性的形式，其特征包括预后不良、化疗诱导的继发性肿瘤发生以及耐药性的出现。我们最近的研究表明，具有两亲性的基于三苯基鏻（TPP）的纳米囊泡（BPPB）对PLX4032（PLX）敏感的MeOV BRAF和MeTRAV BRAF突变细胞系具有强大的ROS依赖性抗癌作用，对MeOV细胞的疗效更为显著。在此，利用这个体外模型，测试了BPPB对PLX耐药（PLX-R）的MeOV BRAF和MeTRAV BRAF突变细胞系的抗肿瘤作用，以寻找对抗黑色素瘤治疗耐药性的新潜在策略。具体而言，我们在剂量和时间依赖性实验中研究了其对细胞活力的影响以及对ROS生成的影响。我们的结果表明，BPPB发挥了强大的抗增殖作用，无论细胞对PLX的获得性耐药如何，且仅在24小时处理时与ROS过量产生相关。此外，就细胞活力而言，PLX-R MeTRAV细胞对24小时BPPB处理的耐受性明显高于PLX-R MeOV细胞。相反，长时间暴露于BPPB在两种细胞系中诱导了相似的反应（MeOV细胞的IC = 87.8 - 106.5 nM，MeTRAV细胞的IC = 81.0 - 140.6 nM）。值得注意的是，BPPB对非致瘤性人角质形成细胞（HaCaT）的细胞毒性较低，因此确定BPPB对CMM细胞具有明显的选择性，选择性指数值（SIs）高达11.58。此外，发现导致50%溶血（HC）的BPPB浓度分别比针对PLX-R MeOV和MeTRAV细胞计算的IC高16 - 173倍和4 - 192倍。相关性研究表明，BPPB通过时间依赖性机制对PLX-R MeOV和MeTRAV细胞发挥细胞毒性作用，而仅在暴露24小时时观察到浓度依赖性机制。最后，仅在72小时处理的PLX-R MeTRAV细胞中可以假定存在ROS依赖性机制。
