Bioinformatics Analysis of IGSF9B Gene in Patients Diagnosed with Colorectal Carcinoma

Cell adhesion molecules (CAMs) are involved i n many cellular processes such as proliferation, apoptosis, metastasis and have the potential to be diagnostic markers and therapeutic targets for malignancies. This study aimed to investigate the role of the IGSF9B gene, a CAM, in colorectal carcinoma via bioinformatics databases. GEPIA2 was used for gene expression analysis, UALCAN for methylation analysis, Kaplan-Meier Plotter for prognosis analysis, cBio Cancer Genomics Portal for gene alteration analysis, and Tumor Immune Estimation Resource databases were used for correlation analyses. In colon adenocarcinoma (COAD) and rectum adenocarcinoma (READ) cohorts, IGSF9B gene expression was decreased compared to normal samples (p< 0.05). Hypermethylation was observed in the IGSF9B gene promoter region in the COAD cohort (p< 10^-12)) and hypomethylation was observed in the READ cohort (p= 5.58x10^-5). IGSF9B gene changes were observed in 36 out of 526 patients (7%). In COAD there was a significant weak positive correlation between IGSF9B gene expression and CD4+ T cells, macrophages, neutrophils, and dendritic cells infiltrations. In READ there was a significant weak positive correlation between IGSF9B gene expression and CD4+ T cells and dendritic cells infiltration. Low IGSF9B gene expression levels were associated with longer OS (p= 0.0079) and RFS (1.8x10^–6). Low expression of IGSF9B gene may be a positive prognostic marker in colorectal cancer patients. Also, alterations in IGSF9B gene may be effective in colorectal carcinogenesis.