Neuron-Specific Gene Family Member 1 is a Potential New Therapeutic Target Associated with Immune Cell Infiltration for Breast Cancer.

Background: Breast cancer (BC) is the most common cancer and is highly morphologically and molecularly heterogeneous. Neuron-specific gene family member 1 (NSG1) is a small single-channel transmembrane protein that consists of 185 amino acids and has been reported in a variety of tumours in recent years. However, the role of NSG1 in BC is unclear.

Objective: This study aimed to explore the role of NSG1 in the pathogenesis and development of BC and its potential as a prognostic marker for BC.

Methods: This study analysed data from The Cancer Genome Atlas database and the Gene Expression Omnibus database to determine the expression level and prognostic value of NSG1 messenger ribonucleic acid in BC. Using this data, we constructed a clinical risk model. Immunohistochemistry was performed in combination with a clinical cohort of 192 patients with BC to explore the NSG1 protein expression in BC. Enrichment analysis was used to predict the biological function of NSG1 in BC. To analyse the correlation between NSG1 and the BC immune microenvironment, a single-cell analysis of NSG1 expression and cells in BC was performed. Kaplan‒Meier curves and Cox regression analysis were utilised to identify the relationship between the expression of NSG1 protein and clinicopathological features and prognosis.

Results: Neuron-specific gene family member 1 is highly expressed in patients with early BC, and its expression suggests a good prognosis for patients with BC. Neuron-specific gene family member 1 is involved in the T-cell receptor complex in BC and is associated with CD8 T cells in the BC immune microenvironment and may induce M1 polarisation of macrophages.

Conclusion: Neuron-specific gene family member 1 is a biomarker of good prognosis in BC. It is associated with the immune microenvironment of BC and may be a potential therapeutic target.