ObjectiveTo investigate the expressions and clinical significance of GATA binding protein 3 (GATA3) and glucose transporter type-1 (GLUT-1) in breast cancer.MethodsA total of 118 patients with breast cancer who were treated surgically in our hospital from May 2019 to May 2021 were collected, and cancer tissue specimens and paracancerous tissue specimens were retained during the surgery for research. Simultaneously, clinical data such as TNM staging and lymph node metastasis were collected and organized. Immunohistochemistry was applied to detect the expression levels of GATA3 and GLUT-1. The relationship between the expression levels of GATA3 and GLUT-1 and the clinicopathological characteristics in the breast cancer patients was analysed; the correlation was analysed by Spearman rank correlation analysis. The relationship between the expressions of GATA3 and GLUT-1 and the prognosis of patients was analysed by the Kaplan-Meier method. The multifactorial Cox regression analyses were used to analyse the influencing factors of the prognosis of breast cancer patients.ResultsThe positive expression rate of GATA3 was 27.97% in breast cancer tissues, which was lower than that of paracancerous tissues (P<0.05), and the positive expression rate of GLUT-1 was 73.73% in breast cancer tissues, which was higher than that of paracancerous tissues (P<0.05). The proportion of breast cancer tissues with GATA3 positive expression was significantly lower in patients with TNM stage Ⅲ, tumour diameter ≥2 cm and lymph node metastasis than that in breast cancer patients with TNM stageⅠ-Ⅱ, no lymph node metastasis and tumour diameter<2 cm (P<0.05), the proportion of GLUT-1 positive expression was significantly higher than that of breast cancer patients with TNM stage Ⅰ-Ⅱ, no lymph node metastasis and tumour diameter<2cm (P<0.05). GATA3 was negatively correlated with GLUT-1 expression in breast cancer tissues (r=－0.229, P<0.05). The 3-year survival rate of patients with GATA3-positive breast cancer tissues (25/33, 75.76%) was higher than that of patients with GATA3-negative expression (20/85, 23.53%) (χ²=27.485, P<0.05). The 3-year survival rate of GLUT-1-positive patients (21/87, 24.14%) was lower than that of patients with negative expression of GLUT-1 (24/31, 77.42%)(χ²=27.503, P<0.05). GATA3, GLUT-1, TNM staging, tumour diameter, and lymph node metastasis were the factors influencing the prognosis of breast cancer (P<0.05).ConclusionThe expressions of GATA3 and GLUT-1 in breast cancer tissues are closely associated with clinicopathological features such as TNM stage and prognosis of patients.