Development of a New Combination Platform for the Early Screening of Gastric Cancer Using Serum Biomarkers

Objective: The combination of pepsinogens (PG I/II) and gastrin-17 (G17) has been used to screen GC in many countries, without satisfactory levels of sensitivity or specificity. The aim of this study was to find a better marker and a new modality in screening early GC. Methods: We measured the serum levels of PG I/II, G17, and prealbumin (PA) from the serum of 481 healthy individuals, 407 benign gastric diseases (BGD), and 416 GC patients using a latex particle-enhanced turbidimetric immunoassay and Sandwich ELISA. Logistic regression analysis was used to obtain the sensitivity and specificity of the combined detection model. Results: When PA was combined with the other biomarkers, the sensitivity and specificity were significantly improved in the ROC curve. The combination of PA+G17+PGI+PGR was the best diagnostic combination for both early and late GC. The AUC, sensitivity, and specificity of the combination for discriminating between early GC and healthy individuals were 0.796, 72.1% and 74.2% respectively. For distinguishing patients with early GC from BGD, the AUC, sensitivity and specificity of the combination were 0.696, 66.7% and 65.4%, respectively. The combination of PA+G17+PGI+PGR improved both the sensitivity and the specificity of GC diagnosis compared with those of the traditional combination of G17+PGI+ PGII +PGR. Conclusion: PA is a valuable indicator for GC and interacts synergistically with PG and G17 in screening for early GC. The new combination platform PA+G17+PGI+PGR may be a potential way for the early screening of GC.

AB1236 KL-6 AS A BIOMARKER FOR SJÖGREN SYNDROME-ASSOCIATED INTERSTITIAL LUNG DISEASE: METHODOLOGY MATTERS

Background:Krebs von den Lungen-6 (KL-6) was recently found to be a serum biomarker for various disease associated interstitial lung disease (ILD) including primary Sjögren syndrome (pSS).1KL-6 is a high-molecular-weight glycoprotein in the Mucin 1 protein group and is majorly expressed by regenerating type II pneumocytes; hence, serum KL-6 levels may reflect the severity of pulmonary damage with regeneration.2Human KL-6 also promotes the proliferation and survival of pulmonary fibroblasts and the differentiation of myofibroblasts, which enhance fibrosis.3, 4Objectives:To evaluate the agreement between the latex particle-enhanced turbidimetric immunoassay with enzyme-linked immunosorbent assay (ELISA) and association with clinical phenotypes.Methods:This retrospective case-control study included 39 patients with pSS, of whom 21 (53.85%) patients developed ILD at the end of follow-up. The serum KL-6 level was compared between latex particle-enhanced turbidimetric immunoassay (Nanopia) and ELISA (MBS2601395; MyBioSource, CA, USA). Electronic medical records were reviewed, including clinical information, images, pulmonary function test, and laboratory results on inclusion, and a chest physician reviewed the results of pulmonary radiography.Results:The two serum KL-6 immunoassays revealed a moderate correlation with a Pearson product-moment correlation coefficient of 0.427. Serum KL-6 levels, measured using ELISA, were 1920.10 ± 1974.26 U/mL and 894.11 ± 788.53 U/mL in the ILD and non-ILD groups, respectively (p = 0.001). The latex particle-enhanced turbidimetric immunoassay for serum KL-6 was 459.62 ± 331.41 U/mL and 265.33 ± 105.37 U/mL in the ILD and non-ILD group, respectively (p = 0.074). The predictive values of serum KL-6 in the area under the receiver-operating characteristic curve were 0.810 and 0.669 in ELISA and latex particle-enhanced turbidimetric immunoassay, respectively.Conclusion:Serum KL-6 is a predicting biomarker in pSS patients who may develop ILD. However, the methodology of immunoassay may influence the efficacy of the prediction and clinical association.References:[1]Chiu Y-H, Lu C-C, Liu F-C, et al. FRI0228 KL-6 AS A BIOMARKER OF DEVELOPING INTERSTITIAL LUNG DISEASE IN PATIENTS WITH SJÖGREN SYNDROME.Ann Rheum Dis. 2019; 78: 793.[2]Yousefi M, Dehghani S, Nosrati R, et al. Aptasensors as a new sensing technology developed for the detection of MUC1 mucin: A review.Biosensors & bioelectronics. 2019; 130: 1-19.[3]Xu L, Yan DR, Zhu SL, et al. KL-6 regulated the expression of HGF, collagen and myofibroblast differentiation.Eur Rev Med Pharmacol Sci. 2013; 17: 3073-7.[4]Ohshimo S, Yokoyama A, Hattori N, Ishikawa N, Hirasawa Y and Kohno N. KL-6, a human MUC1 mucin, promotes proliferation and survival of lung fibroblasts.Biochem Biophys Res Commun. 2005; 338: 1845-52.Acknowledgments:This work was supported by National Defense Medical Center and Tri-Service General Hospital (TSGH-D-109183). The authors thank Kuo’s Yuan In Enterprise co., LTD for supporting Nanopia KL-6 Kit.Disclosure of Interests:None declared

In-line monitoring of latex-particle size during emulsion polymerizations with a high polymer content of more than 60%

The photon density wave (PDW) spectroscopy is established in the fields of biochemistry and food chemistry as an online analytical method for the determination of mean particle sizes.