High expression of DLG3 is associated with decreased survival from breast cancer.

Abnormal expression or activity of proteins that regulate cell polarity can contribute to tumour progression. Discs large homolog (DLG) proteins play crucial roles in the maintenance of cell polarity and tissue morphogenesis. Previous studies of breast cancer patients showed that DLG3 had greater expression in the cancerous tissues than non-cancerous tissues, but the relationship between DLG3 expression and breast cancer progression and prognosis is not clear. Here, we investigated the association of DLG3 expression with breast cancer progression and prognosis using data on clinicopathological parameters from The Cancer Genome Atlas (TCGA) database, with different clinicopathological parameters using ualcan and LinkedOmics, and with different stages and subtypes using immunohistochemical staining. The results indicated greater DLG3 expression in cancerous breast tissues than normal breast tissues and in luminal and Her2+ subtypes than in the triple-negative subtype. DLG3 expression also had a positive correlation with pathologic stage and decreased survival rate. Our data suggest that DLG3 should be considered as a new diagnostic and prognostic biomarker for breast cancer.