A study of the association of vitamin D receptor (VDR) as a predictive biomarker for immune checkpoint inhibitor therapy with immune invasion in colon adenocarcinoma.

Colon adenocarcinoma(COAD) is a primary and aggressive malignancy with the fifth highest mortality rate among cancers, and it is important to discover new strategies. The online database was used to analyze the correlation between Vitamin D receptor (VDR) and COAD, and further explore the immune infiltration and related gene networks.The expression and methylation levels of VDR was analyzed by using Timer database, GEPIA platform and UALCAN database. GeneMANIA database was used to analyze and obtain gene networks that are closely linked to VDR. UALCAN database was used to score the gene effects of VDR in colorectal cancer cell lines. The cBioPortal database was used for the detection of gene mutations. The survival curve analysis was carried out using the GEPIA database. The relationship between VDR expression and immune cell infiltration was analyzed by using the timer database and TISIDB database. TISIDB database was used to obtain VDR-related drug targets.The expression of VDR was significantly lower in COAD(p<0.05). The methylation level of VDR was significantly higher in COAD (p<0.05). The gene mutation rate of VDR in COAD was 2 %. OS and DFS were not associated with changes in the VDR gene in patients with COAD. VDR expression was correlated with CD4+T cell infiltration, macrophage infiltration, neutrophil infiltration, and dendritic cell infiltration. VDR has a clear correlation with ADORA2A, BTLA, CD160, CD244, CD274, CD96, CSF1R, CTLA4, HAVCR2, IL10, IDO1, LAG3, LGALS9, PDCD1, PDCD1LG2, PVRL2, TGFB1, TGFBR1, TIGIT and VTCN1.The expression of VDR is associated with immune infiltration in patients with COAD. VDR may be a new candidate biomarker for determining the level of immune infiltration and predicting immune checkpoint inhibitor therapy.