The Expression Of RPL39L In Esophageal Squamous Cell Carcinoma

Background and PurposeEsophageal squamous cell carcinoma is a common malignant tumor.Due to the high metastasis rate of lymph nodes,liver and lung,the prognosis of esophageal squamous cell carcinoma is poor.Despite the rise in incidence of adenocarcinoma,squamous cell cancer of the esophagus remains the commonest cell type worldwide,and this histological type still accounts for 90% of all esophageal cancers.Despite much research on the disease,its pathogenesis remains unclear.There is increasing evidence that genetic loci are associated with susceptibility to esophageal cancer.Molecular studies of ESCC showed that Tp53 mutation,p16 deletion,increased expression of CDKN2 A and other genetic changes played a role in the occurrence of ESCC.Ribosomal proteins(RPs)play an important role in ribosomal biogenesis.In addition to stabilizing ribosome,RPs also have extraribosomal functions that are involved in DNA repair,apoptosis,drug resistance,growth,proliferation,and chemical resistance.Abnormal ribosomal protein expression can cause various diseases,such as tumors,metabolic diseases,autoimmune diseases and so on.As the homologous protein of RPL39,ribosomal protein L39L(RPL39L)is usually expressed in human testicles and overexpressed in various cancer cells,and can promote lung metastasis of breast cancer cells.However,the expression and role of RPL39 L in esophageal squamous cellcarcinoma have not been studied.In this paper,we apply the qPCR technology to detect the RPL39 L mRNA level from 78 cases of fresh frozen esophageal squamous carcinoma tissues and adjacent tissues,use immunohistochemical method to detect RPL39 L in the expression of 300 cases of esophageal squamous cell carcinomas(ESCC),and analyze the relationship between the expression pattern and the prognosis of patients,so as to further explore the clinical value of early diagnosis,treatment and prognosis of RPL39 L in esophageal squamous cell carcinomas.Materials and Methods Collection of clinical specimensSeventy-eight fresh specimens of esophageal cancer from Linzhou People's Hospital,Anyang City,Henan Province were collected,each of which included cancer and adjacent tissues.Tissues were obtained and stored in liquid nitrogen for RNA extraction.At the same time,the tissue wax blocks of 300 cases of radical resection of esophageal squamous cell carcinoma in this hospital were collected,and the postoperative follow-up data were complete,and tissue microarray was made.MethodThe expression of RPL39 L mRNA was detected by qPCR in 78 cases of fresh frozen esophageal squamous cell carcinoma and paracancer tissues.The expression level of RPL39 L protein in 300 pairs of ESCC tissue chips was detected by immunohistochemistry.SPSS 21.0 statistical software was used to conduct descriptive statistical analysis of the data,and paired t-test was used to analyze the expression of RPL39 LmRNA in the adjacent normal tissues corresponding to cancer.Chi-square test or Fisher exact test was used to evaluate the relationship between RPL39 L protein expression and clinicopathological variables(including patient age,gender,tumor invasion,lesion site,lymph node metastasis,degree of tumor differentiation,and TNM stage).Kaplan-meier method was used to draw the survival curve,and log-rank test was used to test the survival difference.Cox proportional risk model was used to compare therisk ratio(HRs)in univariate and multivariate analyses.Results1)The expression of RPL39 L mRNA in esophageal squamous cell carcinoma tissues were higher than that in the corresponding paracancer tissues,and the difference was statistically significant(P<0.0001).2)The up-regulation rate of RPL39 L protein in esophageal squamous cell carcinoma tissues was higher than that in the corresponding paracancer tissues,with statistical significance(P<0.001).3)The expression of RP39 L protein was related to the lesion site,lymph node metastasis,degree of tumor differentiation and clinical stage.4)The expression level of RPL39 L protein is related to the clinical prognosis of esophageal squamous cell carcinoma.OS of those with high RPL39 L protein expression(n=124)is shorter than that of those with low RPL39 L protein expression(n= 83)(P<0.001).Also,the median survival period of those with high RPL39L protein expression is 17 months,while that of those with low RPL39L protein expression is 47 months.Cox multivariate regression analysis shows that RPL39L protein expression level is an independent prognostic factor for esophageal squamous cell carcinoma.Conclusion1)The expression level of RPL39 L mRNA and protein in esophageal squamous cell carcinoma tissues was higher than that in paracancer tissues.2)The expression level of RPL39 L protein was related to the lesion site,lymph node metastasis,degree of tumor differentiation and clinical stage.3)RPL39L protein expression level was associated with poor prognosis of esophageal squamous cell carcinoma patients.The higher the expression level of RPL39L protein,the shorter the OS of patients.