LEP and major depressive disorder: The leptin and LepRb mRNA levels were significantly increased in patients who diagnosed GC accompanied with depression compared with that of paracarcinoma tissues and GC without depression (depressive GC versus paracarcinoma tissues; 9.3-fold for leptin and 6.5-fold for LepRb, resp.; and depressive GC versus nondepressive GC, 1.4-fold for leptin and 1.4-fold for LepRb, resp).