Decreased plasma level of C-type lectin-like receptor 2 (CLEC-2) in patients with breast cancer

<b>Background:</b> C-type lectin-like receptor 2 (CLEC-2) is involved in platelet activation, tumor metastasis, and vessel differentiation, but its role in breast cancer remains unclear. This study examined the association between clinical status and plasma levels of CLEC-2 in patients with breast cancer. <b>Methods:</b> Plasma CLEC-2 concentrations were measured using ELISA in breast cancer patients and control subjects. A total of 98 breast cancer patients and 98 age-matched control subjects were enrolled. All study participants were female. <b>Results:</b> CLEC-2 concentrations were significantly lower in the breast cancer patients (231.2 [213.5-250.9] ng/mL) than in the controls (249.2 [235.8-263.4] ng/mL, p < 0.0001). Plasma CLEC-2 levels were lower in patients with advanced stages (T3+T4, AJCC III-IV), histologic grade > 3, and tumor size ≥5 cm. Kaplan-Meier analysis revealed a higher overall survival rate in the patients with a high CLEC-2 levels than in those with a low CLEC-2 levels (p = 0.035). Univariate Cox analysis showed that a high CLEC-2 level was independently associated with better overall survival. Spearman correlation analysis showed that CLEC-2 plasma levels were positively correlated with stages T0-T2, grades 1-2, ALT, APRI, and tumor size <2 cm, but negatively correlated with platelet count. <b>Conclusion:</b> Our findings suggest that lower plasma CLEC-2 levels are associated with advanced breast cancer features. CLEC-2 is significantly associated with breast cancer prognosis and may serve as a prognostic marker in patients with breast cancer.