Leptin-LepRb Expressed in Gastric Cancer Patients and Related to Cancer-Related Depression

Depression is the most common psychiatric disorder among cancer patients. Studies have not only highlighted that leptin and its receptor (LepRb) are independent poor prognostic factors in gastric cancer (GC) patients but also shown that the leptin-LepRb is necessary for antidepressant-like behaviors. In this study, we examined the serum and tissue leptin-LepRb expression in GC patients. Enzyme-linked immunosorbent assay showed that depressive GC patients had significantly higher serum leptin-LepRb than healthy donors. Leptin-LepRb levels in GC tissues were also significantly higher than in matched paracarcinoma tissues using real-time RT-PCR. Moreover, we observed that both serum and tissue leptin-LepRb were significantly higher in depressive GC patients than those in nondepressive GC patients. Further, the patients with high tumor stage tend to have higher leptin-LepRb mRNA levels than that with low tumor stage. Together, our findings suggest that leptin-LepRb plays an important role in the pathogenesis and depression in GC. Leptin-LepRb therefore could be a potential diagnostic marker and therapeutic target in GC patients with depression.