Effect of Cryoablation Treatment on the Protein Expression Profile of Low-Grade Central Chondrosarcoma Identified by LC-ESI-MS/MS

The use of cryoablation/cryosurgery in treating solid tumors has been proven as a unique technique that uses lethal temperatures to destroy the tumors and impart better functions for the affected organs. This novel technique recently demonstrated the best clinical results in chondrosarcoma (CSA) with faster recovery, less recurrence, and metastasis. Due to the resistant nature of CSA to chemo and radiation therapy, cryoablation comes to light as the best alternative approach. Therefore, for the first time, we aimed to compare CSA-untreated with cryoablation treated samples to discover some potential markers that may provide various clues in terms of diagnosis and pathophysiology and may facilitate the development of novel methods to treat sarcoma efficiently. To find the altered proteins among both groups, a mass-based label-free approach was employed and identified a total of 160 significantly altered proteins. Among these, 138 proteins were dysregulated with 3 folds, and four proteins were similarly expressed in the untreated group compared to the treated. Interestingly, the differential expressions of proteins from the untreated group showed contrast expressions in the treated group. Furthermore, the functional enrichment analysis revealed that most of the identified proteins from this study were associated with various significant pathways such as glycolysis, MAPK activation, PI3K-Akt signaling, extracellular matrix degradation, etc. In addition, two protein expressions, such as fibronectin and annexin-1, were validated by immunoblot analysis. Therefore, this study signifies the most comprehensive discovery of altered protein expressions to date and the first large-scale detection of protein profiles from CSA-cryoablation treated compared to untreated. This work may serve as the basis for future research to open novel treatment options for chondrosarcoma.

冷冻消融（cryoablation）/冷冻手术（cryosurgery）用于实体瘤治疗已被证实为一种独特的肿瘤消融技术，其通过极端低温破坏肿瘤组织，同时改善受累器官的功能。该新型治疗手段近期在软骨肉瘤（chondrosarcoma, CSA）治疗中展现出最优临床效果，可实现更快术后康复、更低复发率与转移率。鉴于软骨肉瘤对化疗与放疗存在天然耐药性，冷冻消融成为了该疾病的最佳替代治疗方案。
因此，本研究首次对比了未接受冷冻消融治疗与接受冷冻消融治疗的软骨肉瘤样本，旨在发掘潜在生物标志物，这些标志物可为软骨肉瘤的诊断与病理生理学研究提供多维度线索，并助力高效治疗肉瘤的新型疗法开发。为筛选两组样本间的差异表达蛋白，本研究采用了基于质谱的无标记定量蛋白质组学方法，共鉴定出160种显著差异表达蛋白。其中138种蛋白存在表达失调且差异倍数达3倍以上，另有4种蛋白在未治疗组与治疗组中表达水平无显著差异。值得注意的是，未治疗组的差异表达蛋白在治疗组中呈现出完全相反的表达模式。
功能富集分析显示，本研究鉴定的大部分蛋白与多条重要通路密切相关，包括糖酵解、丝裂原活化蛋白激酶（MAPK）激活通路、磷脂酰肌醇3-激酶-蛋白激酶B（PI3K-Akt）信号通路、细胞外基质降解等。此外，本研究通过免疫印迹分析（immunoblot analysis）验证了纤连蛋白（fibronectin）与膜联蛋白-1（annexin-1）的蛋白表达水平。
综上，本研究是迄今为止针对软骨肉瘤冷冻消融治疗组与未治疗组差异蛋白表达最全面的解析，也是首次大规模鉴定该对比组的蛋白质谱。本研究可为未来开发软骨肉瘤新型治疗方案提供核心研究基础。