• Cord blood;
  • diabetes mellitus type 1;
  • gestational diabetes mellitus;
  • maternal blood;
  • placenta;
  • RCAS1


The human tumor-associated receptor-binding cancer antigen expressed on SiSo cells (RCAS1) is considered to play a role in the inhibition of the maternal immune response during pregnancy. The aim of our study was to investigate the expression of RCAS1 protein in the placenta and to compare its concentration in maternal and cord blood sera between normal pregnancies and pregnancies complicated by gestational diabetes mellitus (GDM).

Method of study

Samples were obtained from women with GDM (n = 8), women with type 1 DM (n = 5), and healthy term controls (n = 27) after delivery. Placentas were studied by immunohistochemistry, and real-time polymerase chain reaction. For assessment of RCAS1 concentrations in maternal and cord blood sera, enzyme-linked immunosorbent assay was performed.


The RCAS1 protein mRNA expression in the placentas of patients with GDM was significantly lower than that in the controls (P = 0.005). The maternal blood RCAS1 protein concentration of the GDM cases was also significantly lower than that in the controls (P = 0.0411), whereas the cord blood RCAS1 protein concentration was significantly higher in the GDM and type 1 DM groups than in the controls (P = 0.0311 and P = 0.0192, respectively).


The present results suggest that RCAS1 protein might have an important role in the development of GDM.