微小RNA介导的PTEN下调作为头颈部鳞状细胞癌对PI3Kα抑制剂获得性耐药的一种新型非遗传机制。
MicroRNA-mediated PTEN downregulation as a novel non-genetic mechanism of acquired resistance to PI3Kα inhibitors of head & neck squamous cell carcinoma.
作者信息
Pulito Claudio, Vaccarella Sebastiano, Palcau Alina Catalina, Ganci Federica, Brandi Renata, Frascolla Carlotta, Sacconi Andrea, Canu Valeria, Benedetti Anna, De Pascale Valentina, Donzelli Sara, Fisch Anne-Sophie, Manciocco Valentina, Covello Renato, Pimpinelli Fulvia, Morrone Aldo, Fazi Francesco, Pellini Raul, Muti Paola, Meens Jalna, Karamboulas Christina, Nichols Anthony C, Strano Sabrina, Klinghammer Konrad, Tinhofer Ingeborg, Ailles Laurie, Fontemaggi Giulia, Blandino Giovanni
机构信息
Translational Oncology Research Unit, IRCCS Regina Elena National Cancer Institute, Rome 00144, Italy.
Microbiology and Virology Unit, San Gallicano Dermatological Institute IRCSS, Rome 00144, Italy.
出版信息
Drug Resist Updat. 2025 Jul;81:101251. doi: 10.1016/j.drup.2025.101251. Epub 2025 May 11.
AIMS
Head and neck squamous cell carcinomas (HNSCCs) frequently harbor alterations in the PI3K signalling axis and, particularly, in the PIK3CA gene. The promising rationale of using PI3K inhibitors for the treatment of HNSCC has, however, clashed with the spontaneous development of resistance over time.
METHODS
To identify valuable targets for overcoming acquired resistance to PI3Kα inhibitors in HNSCC, we performed microRNA profiling on a cohort of HNSCC PDXs that were treated with alpelisib, including both responsive and resistant tumors. Using CRISPR/Cas9, siRNA, and PTEN-/- isogenic and alpelisib-resistant cell models, we examined the role of PTEN in resistance acquisition. Phospho-proteomic analysis identified PTEN-dependent phosphorylation events, while PI3Kα inhibitor-resistant organoids were used to assess PLK1 inhibitor efficacy.
RESULTS
We identified microRNAs altered in resistant PDXs, including members of the miR-17-92 cluster. Mechanistically, we observed that the hyperactive c-Myc was recruited to MIR17HG regulatory regions in alpelisib-resistant cells, sustaining miR-17-5p, miR-19b-3p, and miR-20a-5p expression, which downregulated PTEN. PTEN knockout or depletion conferred alpelisib resistance in HNSCC cells. We identified PTEN-dependent phosphorylation events, such as p-PLK1-T210, involved in resistance. Interestingly, pharmacological inhibition of PLK1 strongly reduced the viability of PI3Kα-resistant organoids derived from HNSCC PDXs and cell line models.
CONCLUSION
Overall, this study unveils a novel, microRNA-driven, non-genetic mechanism contributing to acquired resistance to PI3Kα inhibitors in HNSCC. Indeed, linking hyperactive c-Myc to sustain miR-17-92 expression and consequent PTEN downregulation, we also propose that targeting PTEN-dependent downstream effectors, such as PLK1, may offer a powerful therapeutic strategy for resistant HNSCC.
目的
头颈部鳞状细胞癌（HNSCC）经常在PI3K信号轴，尤其是PIK3CA基因中存在改变。然而，使用PI3K抑制剂治疗HNSCC的前景与随着时间推移自发产生的耐药性相冲突。
方法
为了确定克服HNSCC中对PI3Kα抑制剂获得性耐药的有价值靶点，我们对一组用阿培利司治疗的HNSCC人源肿瘤异种移植模型（PDX）进行了微小RNA分析，包括反应性和耐药性肿瘤。使用CRISPR/Cas9、小干扰RNA（siRNA）以及PTEN基因敲除的同基因和阿培利司耐药细胞模型，我们研究了PTEN在耐药性获得中的作用。磷酸化蛋白质组分析确定了PTEN依赖性磷酸化事件，同时使用PI3Kα抑制剂耐药类器官来评估PLK1抑制剂的疗效。
结果
我们鉴定出在耐药PDX中改变的微小RNA，包括miR-17-92簇的成员。从机制上讲，我们观察到在阿培利司耐药细胞中，过度活跃的c-Myc被募集到MIR17HG调控区域，维持miR-17-5p、miR-19b-3p和miR-20a-5p的表达，从而下调PTEN。PTEN基因敲除或缺失赋予HNSCC细胞阿培利司耐药性。我们确定了与耐药性相关的PTEN依赖性磷酸化事件，如p-PLK1-T210。有趣的是，PLK1的药理学抑制强烈降低了源自HNSCC PDX和细胞系模型的PI3Kα耐药类器官的活力。
结论
总体而言，本研究揭示了一种新的、由微小RNA驱动的非遗传机制，该机制导致HNSCC对PI3Kα抑制剂产生获得性耐药。事实上，将过度活跃的c-Myc与维持miR-17-92表达以及随后的PTEN下调联系起来，我们还提出靶向PTEN依赖性下游效应物，如PLK1，可能为耐药HNSCC提供一种有效的治疗策略。
Zotero 插件