Methodological study and clinical value of serum exosome Annexin A11 in pancreatic cancer / 中华检验医学杂志

ABSTRACT

Objective:To explore a method for detecting recombinant human Annexin A11 (ANXA11) in serum exosomes of pancreatic cancer patients, and then primarily evaluate the clinical value of ANXA11 in pancreatic cancer patients.Methods:A prospective study was conducted and serum specimens from 70 patients diagnosed with PC, 15 patients diagnosed with benign pancreatic mass and 70 patients diagnosed with pancreatitis from the Affiliated Hospital of Nantong University were collected from December 2016 to July 2019. 70 healthy subjects during the same period were selected as control group. The abundance of ANXA11 in serum and exosomes-free serum were detected through parallel reaction monitoring (PRM) basing on high-resolution, high-precision mass spectrometer. Dot immunoblotting created by ourselves for detecting ANXA11 in exosomes and then the methodological evaluation were carried out. Levels of ANXA11 in exosomes in all subjects were statistically analyzed. Moreover, the areas under the curve (AUC) of receiver operating characteristic (ROC) curves were adopted to evaluate the diagnostic efficacy of ANXA11, CA19-9, CEA on PC. The relationship between ANXA11 and clinicopathological parameters as well as prognosis of PC patients was analyzed in the next moment. For analysis, the Mann-Whitney U test was used for comparing between either two groups, and the kruskal-wallis test was used for comparison among four groups. Results:The detection of serum exosome ANXA11 has high sensitivity and repeatability by the method of self-established dot immunoblotting. ANXA11 increased most significantly in the PC group, and the difference was statistically significant ( Hc=58.079, P<0.01) compared with other three groups. ROC curve analysis showed that the diagnostic performance of ANXA11(area under the curve (AUC=0.836) was higher than CEA (AUC=0.656) and equal to CA19-9 (AUC=0.870). The combination of ANXA11 and CA19-9 could improve the sensitivity of diagnosing PC and maintain good specificity. The level of serum exosome ANXA11 before treatment in PC patients was not related to age, gender, tumor size, tumor growth site, lymph node metastasis, distant metastasis and TNM stage ( Z values are 0.052,-0.285,-0.402,0.324,0.888,0.658,1.734, P>0.05). Furthermore, during the 10th day after surgical treatment, the level of ANXA11 showed no statistical difference compared with that before surgery ( Z value is -1.569, P=0.12). The survival time of PC patients was related to the presence of lymph node metastasis, distant metastasis, TNM staging and treatment protocols (χ 2 values are 9.354,6.086,9.389,16.998, P<0.05), while had no correlation with levels of CEA, CA19-9 and ANXA11 (χ 2 values are 1.516, 0.011, 0.159, P>0.05). Conclusions:This study successfully established an original method for detecting ANXA11 levels in serum exosomes of human. Serum exosomes ANXA11 combined with CA19-9 could improve the diagnostic sensitivity of PC.