Expression And Significance Of LMO2 In Primary Squamous Cell Carcinoma Of Oral Cavity And Parotid Gland

Part I Bioinformatics analysis of the biological function and prognostic value of LMO2 in oral squamous cell carcinomaBackground:Oral Squamous Cell Carcinoma(OSCC)is the most common malignant tumor in the oral and maxillofacial region.It is easily overlooked in the early stage and has a poor prognosis in the late stage.Surgery often causes a wide range of tissue defects and dysfunction.Early diagnosis,treatment and prognosis prediction of OSCC have become a global concern.Biomarkers are important means for early diagnosis,treatment and prognosis prediction of cancer.With the continuous exploration of researchers,more and more biomarkers related to OSCC have been found,and the role of biomarkers in the diagnosis and treatment of OSCC has also been paid more and more attention.Bioinformatics is an interdisciplinary subject that collects,processes,stores,analyzes and outputs biological information in life sciences,especially genomics and proteomics,by comprehensively using methods and tools from multiple fields such as mathematics and information science.Bioinformatics can not only solve complex biomedical problems,but also play a huge role in disease prevention,diagnosis,treatment,and even the development of new drugs.Objective:In the first part of this study,bioinformatics methods were used to find biomarkers related to the diagnosis and prognosis of OSCC,so as to provide new ideas for the diagnosis,treatment and prognosis prediction of OSCC.Methods:The differentially expressed genes between OSCC and oral normal tissues were screened through GEO database and TCGA database,and then the differential genes were analyzed for prognosis,and the genes related to prognosis were selected for retrieval in Pubmed,Web of Science and other databases,and comprehensive domestic and foreign research.If necessary,select a suitable target gene for follow-up research.ROC curve analysis,co-expression gene analysis,PPI network construction,functional enrichment analysis and immune infiltration analysis were performed on the target genes to explore the reliability of target genes as OSCC diagnostic and prognostic markers and their biological significance in OSCC.Results:1.The analysis results of GEO database and TCGA database showed that the expression of LMO2 in OSCC was lower than that in oral normal tissues(P<0.05).2.The prognostic analysis of LMO2 showed that the expression of LMO2 was positively correlated with the overall survival of OSCC patients,and patients with high LMO2 expression may have a better prognosis(P<0.05).3.The results of ROC curve analysis showed that it is more reliable to diagnose OSCC by detecting the expression of LMO2(AUC=0.831,P<0.05).4.The results of co-expression gene analysis showed that the correlation between LMO2 and other genes in OSCC was low,and LMO2 may play an independent role in OSCC(Pearson coefficient <0.5).5.The results of PPI analysis and functional pathway enrichment analysis showed that LMO2 protein was associated with TAL1,GATA1,GATA2,GATA3,LDB1,RLIM,SSBP2(confidence>0.7),and these protein functional pathways were mainly enriched in hematopoietic diseases.In the process of development,some of them are related to the occurrence and progression of solid tumors.6.The results of immune infiltration analysis showed that with the increase of LMO2 expression,the infiltration levels of plasmacytoid dendritic cells(Pearson=0.579,P<0.001)and B cells(Pearson=0.522,P<0.001)increased,suggesting that LMO2 may be involved in the immune infiltration process of OSCC and play a role in the immune regulation of OSCC.Conclusion:1.The expression of LMO2 in oral squamous cell carcinoma is lower than that in oral normal tissues,and it is reliable to distinguish OSCC from normal oral tissues by detecting the expression of LMO2..2.The expression of LMO2 is positively correlated with the prognosis of patients,and LMO2 may be a protective factor for the prognosis of patients with oral squamous cell carcinoma.3.LMO2 may be involved in regulating the immune infiltration process of oral squamous cell carcinoma.Part II Expression and significance of LMO2 in primary squamous cell carcinoma of oral cavity and parotid glandBackground:In the first part of this study,bioinformatics analysis of multiple databases showed that compared with normal oral tissues,LMO2 gene was low expressed in oral squamous cell carcinoma,and LMO2 expression was related to the prognosis of patients,which may be used as a diagnostic and prognostic marker of OSCC,but the true expression of LMO2 protein in OSCC has not been verified.Primary squamous cell carcinoma(PSCC)of parotid gland is a rare malignant tumor of parotid gland.Compared with other malignant tumors of parotid gland,its clinical manifestations are nonspecific,but its invasion is stronger and its prognosis is worse.Both PSCC of parotid gland and OSCC belong to oral and maxillofacial squamous cell carcinoma.The relationship between parotid gland and oral anatomy and physiology is very close.OSCC can metastasize to parotid gland and PSCC of parotid gland can also metastasize to oral cavity.Histologically,parotid gland develops from primitive oral epithelium induced by surrounding mesenchymal.In pathology,case reports and cohort studies over the years also believe that there is no significant difference between the two.The etiology and mechanism of parotid PSCC are unknown,and there are no systematic reports on the relationship between the disease and OSCC and specific gene targets.Objective:Combined with the correlation between parotid PSCC and OSCC,we speculate that the expression level of LMO2 in parotid PSCC may be similar to OSCC.In the second part of this study,the expression of LMO2 in OSCC and parotid PSCC was detected by immunohistochemical staining,and its correlation with OSCC and PSCC was discussed,so as to provide a new idea for the diagnosis,treatment and prognosis of OSCC and parotid PSCC.Methods:1.We selected 44 samples of OSCC and 10 samples of normal oral tissues,detected the difference of LMO2 expression in OSCC and normal oral tissues by immunohistochemical(IHC)staining experiment,and discussed the relationship between LMO2 and different clinicopathological features of OSCC patients.2.We selected 5 samples of parotid PSCC and 10 samples of normal parotid tissue to detect the difference of LMO2 expression between parotid PSCC and normal parotid tissue by immunohistochemical staining.Results:1.The expression of LMO2 protein in OSCC was lower than that in normal oral tissues(P<0.001).2.The expression level of LMO2 protein was correlated with the history of alcoholism,clinical stage and pathological grade of OSCC patients,and alcoholics were lower than non alcoholics(p<0.05);Clinical stage Ⅲ and Ⅳ were lower than stage Ⅰ and Ⅱ(p<0.05);Those with moderate differentiation were lower than those with high differentiation(p<0.05),and those with low differentiation were lower than those with high differentiation(p<0.05).3.The expression of LMO2 protein in parotid PSCC was lower than that in parotid gland normal tissue(P<0.001).Conclusion:1.The expression of LMO2 protein in OSCC is lower than that in normal oral tissues,OSCC and normal oral tissues can be distinguished by detecting the expression of LMO2 protein in the samples.2.The expression level of LMO2 protein is correlated with the patient’s alcoholism history,clinical stage and pathological grade,which may provide some guidance for the prognosis of OSCC patients.3.The expression of LMO2 in parotid PSCC is lower than that in parotid gland normal tissue,parotid PSCC and normal parotid tissue can be distinguished by detecting the expression of LMO2 protein in the sample..