On-tissue chemical derivatization enables spatiotemporal heterogeneity visualization of oxylipins in esophageal cancer xenograft via ambient mass spectrometry imaging  

作　　者：Jialin Liu Qingce Zang Xinzhu Li Xinyi Tu Ying Zhu Lingzhi Wang Zitong Zhao Yongmei Song Ruiping Zhang Zeper Abliz 

机构地区：[1]State Key Laboratory of Bioactive Substance and Function of Natural Medicines,Institute of Materia Medica,Chinese Academy of Medical Sciences and Peking Union Medical College,Beijing 100050,China [2]State Key Laboratory of Molecular Oncology,Cancer Institute,Cancer Hospital,Chinese Academy of Medical Sciences and Peking Union Medical College,Beijing 100021,China [3]Key Laboratory of Mass Spectrometry Imaging and Metabolomics(Minzu University of China),National Ethnic Affairs Commission,Beijing 100081,China [4]Center for Imaging and Systems Biology,College of Life and Environmental Sciences,Minzu University of China,Beijing 100081,China

出　　处：《Chinese Chemical Letters》2023年第11期238-242,共5页中国化学快报（英文版）

基　　金：supported by the National Natural Science Foundation of China(No.21927808);the Chinese Academy of Medical Science(CAMS)Innovation Fund for Medical Sciences(CIFMS,Nos.2022-I2M-2-002 and 2021-1-I2M-028).

摘　　要：On-tissue chemical derivatization(OTCD)effectively enhances ionization efficiency of low abundant and poorly ionized functional molecules to improve detection sensitivity and coverage of mass spectrometry imaging(MSI).Combination OTCD and MSI provides a novel strategy for visualizing previously undisclosed metabolic heterogeneity in tumor.Herein,we present a method to visualize heterogeneous metabolism of oxylipins within tumor by coupling OTCD with airflow-assisted desorption electrospray ionization(AFADESI)-MSI.Taking Girard’s P as a derivatization reagent,easily ionized hydrazide and quaternary amine groups were introduced into the structure of carbonyl metabolites via condensation reaction.Oxylipins,including 127 fatty aldehydes(FALs)and 71 oxo fatty acids(FAs),were detected and imaged in esophageal cancer xenograft with AFADESI-MSI after OTCD.Then t-distributed stochastic neighbor embedding and random forest were exploited to precisely locate the distribution of oxylipins in heterogeneous tumor tissue.With this method,we surprisingly found almost all FALs and oxo FAs significantly accumulated in the core region of tumor,and exhibited a gradual increase trend in tumor over time.These results reveal spatiotemporal heterogeneity of oxylipins in tumor progression,highlighting the value of OTCD combined with MSI to gain deeper insights into understanding tumor metabolism.

关 键 词：On-tissue chemical derivatization Ambient mass spectrometry imaging OXYLIPINS Esophageal cancer Metabolic heterogeneity 

分 类 号：R73[医药卫生—肿瘤]