Multi-omics revealed GOT1/ALDH3A1 pathway attenuated head and neck squamous cell carcinoma and increased cisplatin sensitivity through ROS induced by mitochondrial dysfunction

Current treatment options for head and neck squamous cell carcinoma (HNSCC) are limited. Aspartate aminotransaminase (GOT1) plays an important role in cancer development but its role in HNSCC remains unknown. We combined proteomics and metabolomics to identify high GOT1expression in human cancer tissues. The effects of GOT1 knockdown on cancer cell proliferation were confirmed using CCK8, wound healing assays, colony formation assays, and EdU assays. The anti-apoptotic ability of cancer cells was evaluated using TUNEL assay and flow cytometry. GOT1 knockdown caused mitochondrial dysfunction and was characterized by reduced mitochondrial membrane potential and altered expression of mitochondrial electron transport chain complexes and key transcription factors, as measured by JC-1 and qRT-PCR. Given that mitochondria are the primary source of reactive oxygen species (ROS), we assessed cellular ROS and mitochondrial superoxide levels by flow cytometry and found a significant increase. GOT1 knockdown increased the sensitivity of cells to cisplatin and decreased the volume of tumors in vivo. In summary, GOT1 knockdown inhibited proliferation and promoted apoptosis via ROS overproduction from mitochondrial dysfunction, thereby increasing cisplatin sensitivity. RNA-seq further identified aldehyde dehydrogenase 3A1 (ALDH3A1) as potentially downstream target of GOT1. These findings suggest that GOT1 knockdown may improve clinical outcomes in HNSCC.

头颈部鳞状细胞癌（head and neck squamous cell carcinoma, HNSCC）目前的临床治疗方案十分有限。天冬氨酸转氨酶（aspartate aminotransaminase, GOT1）在癌症发生发展中发挥重要作用，但其在头颈部鳞状细胞癌中的功能尚不清楚。本研究联合运用蛋白质组学与代谢组学技术，在人类癌组织中鉴定出GOT1的高表达。通过CCK-8实验、划痕愈合实验、克隆形成实验及EdU掺入实验，验证了GOT1敲低对癌细胞增殖的影响。采用TUNEL染色法与流式细胞术，评估了癌细胞的抗凋亡能力。经JC-1染色与实时荧光定量聚合酶链反应（quantitative real-time polymerase chain reaction, qRT-PCR）检测发现，GOT1敲低会引发线粒体功能障碍，表现为线粒体膜电位降低、线粒体电子传递链复合物及关键转录因子的表达异常。鉴于线粒体是活性氧（reactive oxygen species, ROS）的主要产生来源，本研究通过流式细胞术检测了细胞内活性氧与线粒体超氧化物水平，发现其水平显著升高。GOT1敲低可增强细胞对顺铂的敏感性，并在体内缩小肿瘤体积。综上，GOT1敲低通过线粒体功能障碍引发活性氧过度生成，进而抑制癌细胞增殖并促进其凋亡，最终增强了癌细胞对顺铂的敏感性。通过RNA测序（RNA-seq），本研究进一步鉴定出醛脱氢酶3A1（aldehyde dehydrogenase 3A1, ALDH3A1）可能为GOT1的潜在下游靶标。上述研究结果表明，GOT1敲低或可改善头颈部鳞状细胞癌患者的临床预后。