Mylk And MYL9Gene Expression In Non Small Cell Lung Cancer By Using The Gene Set Enrichment Analysis

Background and objective Non small cell lung cancer (NSCLC) is one of the most common malignant tumors in the world. Which is closely related to recurrence, metastasis and treatment and prognosis of patients, and is the leading cause of death of lung cancer patients. But its pathogenesis is still not clear. This study aims to screen the key genes and pathways in non small cell lung cancer occurrence and development, using molecular biology experiment to validate the key genes expression, providing a new way for the development of non small cell lung cancer, and providing a new scientific basis for molecular diagnosis and a new target in the treatment of lung cancer.Methods1、 Using gene set enrichment analysis (GSEA) and set a single gene in a single set of data element analysis (meta-analysis, meta) method of bioinformatics, to screen out the key genes and pathways of non small cell lung cancer development.2、The quantitative real-time PCR (QRT-PCR) and Western blot (WB) methods were performed in80patients with non small cell lung cancer tissues, matched adjacent tissues and80cases of normal lung tissue, to predict the key genes of Myosin light chain kinase (MYLK) and Myosin regulatory light chain9(MYL9), and verify from gene and protein level to explore its relationship with clinical pathological parameters.3、Further by using multivariate Logistic regression to analyse MYLK and MYL9with clinicopathological parameters.Results1、 Six sets of microarray data were screened out from the gene chip database (Gene Expression omnibus, GEO) by using GSEAand Meta-analysis method.15common up-regulated pathways and9down regulated pathways were successfully screened in non small cell lung cancer that played an important role in the development. The up-regulated co-pathways of significantly genes including(CANT1、DDB1、ENTPD5、ENTPD6、ITPA、 LIG1、NME1、PCNA、PKM2、POLD1、POLD2、POLE2、POLE3、POLR1C、 POLR2A、POLR2D、POLR2F、POLR2H、PRIM1、RFC2、RFC3、RFC4、 RFC5、RPA2、RPA3、RPA4、RRM2and SHFM1(P<0.01), and down-regulated genes CALM1、THBS1、CSF3、BMP2、IL6ST、MYLK、ROCK2、IL3RA、 MYL9、PPP2CA、CSF2RB、CNAQ、GRIA2=IL10RA、IL10RB、IL11RA、 LIFR、PLCB4and RAC3)(P<0.01).Some genes of up-regulated genes DDB1、LIG1、NME1、PCNA、 PKM2、POLD1、POLR2A、PRIM1、RFC4、 RPA2、RRM2,down-regulated genes THBS1、CALM1、BMP2、IL6ST、 CSF3、ROCK2、PPP2CA、IL10RA、IL3RA and MYLK were analyzed by Cormine, which have been reported in non small cell lung cancer and closely related to the occurrence and development. This research selects the MYLK and MYL9genes to verify its expression in non small cell lung cancer, to study their key roles on involvement in vascular smooth muscle contraction pathway and focal adhesion pathway in non-small cell lung cancer development.2、 MYLK and MYL9mRNA and protein were expressed in cancer tissues was significantly lower than in adjacent cancer tissues and normal lung tissues (P <0.05), para cancer tissues and normal lung tissue was no statistical difference (P>0.05). Their expression levels in NSCLC with lymphatic metastasis were significantly higher than that without lymphatic metastasis (all P<0.05). Lower levels were found in smokers and male whereas TMN staging, differentiation and pathohistological type have no impact (P>0.05).3、 Logistic regression analysis showed that:female, smokers and lymph node metastasis group increase the expression of MYLK and MYL9.Conclusion1、 The expression of MYLK and MYL9gene in non small cell lung cancer were down-regulation expression, suggesting that MYLK and MYL9genes play a similar role of tumor suppressor genes in non small cell lung cancer.2、 The results suggest that MYLK and MYL9expression was positively correlated with lymph node metastasis,which may be associated with non small cell lung cancer invasion and metastasis, prognosis and treatment and possible for non small cell lung cancer plays a guiding role.3、 The low expression of MYLK and MYL9gene can increase mutation, promote cell proliferation and accelerate the carcinogenic process, which have a potentially important value for the treatment and prognosis of non-small cell lung cancer, may be a new therapeutic targets for non-small cell lung cancer. Following the research team will further validate biological function on these two genes.