Assessment of combined expression of B7-H3 and B7-H4 as prognostic marker in esophageal cancer patients

The co-stimulatory ligands of B7-family have been confirmed to play an important role in negatively regulating the T-cell mediated anti-tumor immunity. In addition, these inhibitory molecules are also aberrantly expressed on various human cancers tissues, and significantly associated with cancer progression and patients' poor prognoses. We have previously reported that B7-H3 and B7-H4 ligands are highly expressed in human esophageal cancer tissues. Herein, we tried to further analyze the value of their combined expression on prognostic prediction for esophageal cancer patients. We found that the combined expression of both B7-H3 and B7-H4 could be used as a valuable risk factor for predicting the prognosis of esophageal cancer patients (P=0.003). Moreover the status of these patients with high expression of both B7-H3 and B7-H4, was positively and significantly associated with the tumor invasion depth (P=0.0414) and TNM stage (P=0.0414). The Cox multivariate proportional hazards regression analysis revealed that the tumor size (P=0.007), the TNM stage (P=0.024) and the status of both B7-H3 and B7-H4 high expression (P=0.011), could be used as an independent risk factor for predicting patients' postoperative prognosis, respectively. In conclusion, our data indicated that the combined application of B7-H3 and B7-H4 expression can be effectively used as a prognostic marker in esophageal cancer patients.