Effect of CD74 on the prognosis of patients with resectable pancreatic cancer

BACKGROUND: CD74 is known as a type II transmembrane glycoprotein that is associated with the major histocompatibility complex class II α and β chains. Recent studies have demonstrated that the expression of CD74 is also linked to some forms of tumors. The present study was to assess the effect of CD74 expression on the prognosis of resectable pancreatic ductal adenocarcinoma(PDAC). METHODS: Forty-six patients who had received a curative resection of primary PDAC and postoperative chemotherapy were included in this study. Immunohistochemical staining was conducted of CD74 on paraffin-embedded tumor sample slices. The patients were grouped according to CD74 staining: CD74(-): CD74 positive tumor cells 【25%; and CD74(+): CD74 positive tumor cells ≥25%. The correlation of CD74 expression level with clinicopathological features and cumulative survival rate was calculated. RESULTS: The numbers of CD74(+) and(-) patients were 32 and 14, respectively. CD74(+) patients showed a high rate of perineural invasion(P=0.007). The 3- and 5-year cumulative survival rates of CD74(-) patients were significantly higher than those of CD74(+) patients(62% and 41% vs 9% and 0%, P=0.000). Multivariate analysis showed that CD74 expression and lymphatic permeation were the independent prognostic indicators. CONCLUSIONS: The overexpression of CD74 is a key factor associated with perineural invasion. Lower-stage(I and II) PDAC patients with CD74 overexpression have a poor prognosis even if they receive a curative resection. CD74 can be used as a prognostic indicator for resectable PDAC.

Enhanced resistance of Portunus trituberculatus to Vibrio alginolyticus by selective breeding

We established a line (screened) of Portunus trituberculatus by selectively breeding individuals that survived from challenge with Vibrio alginolyticus, and compared the response of screened and unscreened (control) P. trituberculatus challenged with V. alginolyticus. We measured superoxide dismutase, catalase, acid phosphatase, alkaline phosphatase, and peroxidase activity and the content of hemocyanin in the plasma and phenoloxidase activity in serum. The cumulative survival rate after 24-h challenge with V. alginolyticus was significantly higher in the screened crabs than in the unscreened crabs (P<0.05). T-SOD and PO activity were significantly lower in the screened stock than in the unscreened stock (P<0.05). POD, CAT, and ACP activity and hemocyanin content were significantly higher in the screened stock than in the unscreened stock. Our results suggest that the screened stock was more resistant to infection. Furthermore, the indices we measured may be used to evaluate the health state of P. trituberculatus.