Abstract:

Objective    To detect expression of sHLA-G in the patients with gastric cancer or precancerous lesions, and to explore its diagnostic significance.  Methods    sHLA-G was detected by ELISA in 82 cases with gastric cancer, 39 cases with gastric intraepithelial neoplassia, 36 cases with atrophic gastritis, 52 cases with superficial gastritis and 67 cases of healthy controls, while the levels of carcino-embryonic antigen (CEA) was also simultaneously detected. The diagnostic value of sHLAG and its correlations with clinicopathological features were analyzed.  Results     The level of sHLA-G was significantly higher in gastric cancer  than those in gastric intraepithelial neoplassia, atrophic gastritis, superficial gastritis and the control group(P<0.001, respectively). The level of sHLA-G was significantly higher in gastricintraepithelial neoplassia than that in the control group(P<0.05). The levels of CEA in gastric cancer was significantly higher than that in the healthy control, superficial gastritis, atrophic gastritis, and gastric intraepithelial neoplassia(P<0.01, respectively). ROC curve analysis showed that AUC for sHLA-G was 0.814, which was significantly higher when compared with the AUC of CEA(0.692, P=0.01). The combined AUC of sHLA-G and CEA was 0.846, which was significantly higher when compared with the AUC of sHLA-G or CEA(P＜0.05; P<0.001). The cutoff value of sHLA-G for diagnosis was 101.37U/mL, while the diagnostic sensitivity, specificity, positive predictive value, negative predictive value and accuracy rate were 73.2%, 82.5%, 63.8%, 87.9% and 79.7%, respectively. The level of sHLA-G in gastric cancer was significantly correlated with age and tumor size (P<0.05, respectively), and  no significant correlations between the level of sHLA-G and other clinicopathological factors were identified(P>0.05, respectively).  Conclusions     HLA-G plays an important role in the pathogenesis and progression of gastric cancer, and detection of sHLA-G is helpful for the early diagnosis of gastric cancer and its precancerous lesions. Therefore, sHLA-G might serve clinically as a potential biomarker for the early diagnosis of gastric cancer.

Key words: Soluble human leukocyte antigen G; Stomach neoplasms; Carcino-embryonic antigen