A Research On Detecting Genes Associated To Oral Squamous Cell Carcinoma(OSCC)

Oral squamous cell carcinoma(OSCC),which represents more than 90% of all oral cancers,represents the most frequent of all oral neoplasms in the world.Genetics plays an important role in the etiopathogenesis of oral squamous cell carcinoma.However,the investigation of the molecular mechanism of OSCC is still incomplete.In order to identify genes associated with OSCC,researchers usually focus on testing if the mean expression level of a gene among OSCC patients is different from that among non-OSCC patients.Actually,genes having different variances between two biological states(cancers vs.controls)also have biological meaning.Variance is another important measure in statistics,representing the amount of information contained in data sets.In general,The variance is larger,the more information the data set contains.In this article,we introduced a new approach to detect OSCC-associated genes,in which we not only compare mean difference,but also variance difference between cases and controls.Differential analysis of gene expression has been successfully applied to detect disease-associated genes for complex human diseases,such as melanoma,serous ovarian cancer,lung adenocarcinoma,and HNSCC.However,according to the existing literature,we can see that there is no analysis for detection of differentially variable(DV)gene probes in OSCC.Based on two OSCC datasets from Gene Expression Omnibus,one of the most public database,we identified 456 DV gene probes,in addition to 2,375 differentially expressed(DE)gene probes in this article.In the interest of distinguishing the effects of the 2,375 DE gene probes and 456 DV gene probes on OSCC,we did comprehensive analysis and found that there are 2,193 DE-only probes,274 DV-only probes,and 182 DE-and-DV probes.DAVID functional analysis showed that genes corresponding to DE-only,DV-only,and DE-and-DV probes were enriched in different KEGG pathways,indicating they play different roles in OSCC.This new approach can be used to investigate the genetic risk factors for other complex human diseases.