Expression and prognosis analyses of Dectin-1 cluster genes in patients with lung adenocarcinoma (LUAD) and the association with immune checkpoint molecules

Abstract

Reviews The Dectin-1 cluster comprises seven members: CLEC-12A, CLEC-12B, CLEC-1A, CLEC-7A, CLEC- 2, CLEC-9A and OLR1. These members have been demonstrated to be involved in the tumorigenesis, progression, and metastasis of several cancers. However, little is known about their roles in human lung adenocarcinoma (LUAD). The expression patterns of the Dectin-1 cluster were analyzed via the ONCOMINE and GEPIA databases. We evaluated the prognostic value of the Dectin-1 cluster in patients with LUAD using the Kaplan-Meier plotter and GEPIA. Differential expression was validated with the EMBL-EBI database, and protein expression was analyzed with the HPA database. In addition, protein-protein interaction network, GO, and KEGG analyses were conducted. Finally, the correlations between CLEC-12A and immune molecules (immune inhibitors and MHC molecules) were investigated via TISIDB and GEPIA. The expression levels of Dectin-1 cluster genes were downregulated in LUAD tissues compared to those in normal lung tissues. The expression levels of CLEC-12A, CLEC-12B, CLEC-2, and CLEC-9A correlated with tumor stage, and CLEC-12A and CLEC-12B were significantly associated with survival in patients with LUAD. The seven genes mostly participated in immune regulation processes and were involved in autoimmune disorders and hematological malignancies. Finally, correlation analyses revealed CLEC-12A expression was associated with most immune inhibitors and MHCs. CLEC-12A was positively related to PD-1, PD-L1, PD-L2, CTLA4, TIM3, and LAG3. In conclusion, our findings suggest that CLEC-12A and CLEC-12B can be used as prognostic biomarkers in LUAD. CLEC-12A expression was associated with immune checkpoint molecules, and CLEC-12A may be a potential assistant target to improve the efficacy of immune checkpoint inhibitors immunotherapy.