Screening And Identification Of Serum Differential Metabolites In Feline Mammary Carcinoma

Feline mammary carcinoma(FMC)has the characteristics of high malignancy,strong invasion,easy metastasis with blood and lymph,and high mortality.It is one of the most common malignant tumors in feline.The cause of FMC is not clear.In the early stage of mammary carcinoma,the systemic symptoms of cats are not obvious and difficult to detect.When the cat has obvious systemic symptoms,almost all of them have metastases.The later the diagnosis of the disease,the lower the survival rate of the cat,so the early detection,diagnosis and treatment of FMC has important clinical significance.In this study,10 samples of breast tumor tissue collected from cats were selected for histopathological diagnosis.Six samples of FMC and 6 samples of healthy control group were detected by Liquid chromatography-mass spectrometry(LC-MS)non-target metabolomics.T-test,principal component analysis(PCA)and orthogonal projects to latent structures-discriminant analysis(OPLS-DA)were used to screen the results of LC-MS non-target metabolomics.According to the P value of t-test is less than 0.05,and the variable importance in the projection(VIP)of OPLS-DA model is greater than 1,the differential metabolites were screened.Then,the selected metabolites were analyzed by hierarchical cluster analysis(HCA).The selected differential metabolites were mapped by the Kyoto Encyclopedia of Genes and Genomes(KEGG)and Metabo Analyst 4.0.The target metabonomics technology based on multiple reaction monitoring(MRM)was used to quantify the objective differential metabolites and verify the accuracy of non-target metabonomics results.In 10 cases of feline breast tumors,6 cases were diagnosed as FMC and 4 cases as benign breast tumors.Results a total of 199 differential metabolites were identified,of which 44 were down-regulated and 155 were up-regulated.All the differential metabolites participated in 77 metabolic pathways.According to the influence degree and enrichment degree of metabolic pathways where metabolites are located,as well as the role of metabolites themselves in the development of FMC.The 11 differential metabolites of L-Glutamate,L-alanine,ergothioneine,indolelactic acid,creatine,succinate,inosine,adenine,hypoxanthine,uric acid and choline were closely related to the occurrence and development of FMC.According to the LC-MS non-target metabolomics results,7 target metabolites including betainnicotinate,5'-S-Methyl-5'-thioadesine,choline,cytosine,L-alanine,L-glutamic acid,creatinine were selected for MRM target metabolomics verification.The verification results were consistent with the LC-MS non-target metabolomics detection resultsEleven differential metabolites including L-Glutamate,L-alanine,ergothioneine,indolelactic acid,creatine,succinate,inosine,adenine,hypoxanthine,uric acid and choline were successfully identified.The results suggest that during the occurrence of FMC,the body will mobilize a large number of substances to participate in the metabolic processes such as energy metabolism,cell biosynthesis and lipid metabolism.The results provide a new research direction for further exploring the relationship between differential metabolites and the occurrence and development of FMC,as well as the diagnostic methods of FMC,and provide a theoretical basis for in-depth analysis of the molecular mechanism of FMC.