More importantly, further correlation analyses revealed that high stromal expression of PD-L2 in NPC was negatively associated with tumor T classification, recurrence and metastasis and advanced clinical stage, which suggested that stromal PD-L2 plays an antitumor role, whereas tumor PD-L2 may provide a selective advantage in NPC tumorigenic processes. The gene discussed is PDCD1LG2; the disease is nasopharyngeal carcinoma.