Differential diagnosis of gastric low- and high grade dysplasia using C6orf15 protein

Objective To investigate the expression of C6orf15 protein in gastric endoscopic biopsy specimens and its usage as an ancillary diagnostic biomarker in determining the grade of gastric dysplasia. Methods We selected 102 patients with gastric endoscopic biopsy specimens from Jinling Hospital. These were divided into four groups: 22 cases of gastric mucosal benign lesions, 28 with low-grade dysplasia (LGD, intestinal-type: 21 cases，foveolar-type: 7cases), 28 with high-grade dysplasia (HGD, intestinal-type: 20 cases，foveolar-type: 8 cases), and 24 cases of gastric adenocarcinoma. We examined the expressions of C6orf15, P53, and Ki67 in 102 gastric endoscopic biopsy specimens, including 47 cases with accompanying endoscopic submucosal dissection (ESD) specimens, using immunohistochemistry. Results In gastric HGD and gastric adenocarcinoma, the c6orf15 protein exhibits diffuse and strong cytoplasmic expression in tumor cells. Conversely, in gastric LGD and benign gastric mucosal lesions, the c6orf15 protein shows negative or faint yellow cytoplasmic staining. The expression rate of C6orf15 in high-grade gastric dysplasia (HGD, 93 %) and gastric adenocarcinoma (100 %) was significantly higher than in the gastric mucosal benign lesion group (0 %) and the low-grade dysplasia (LGD, 7 %) group (P < 0.001). Conclusion The detection of C6orf15 protein expression could serve as a valuable adjunctive diagnostic tool for distinguishing between gastric HGD, LGD, and benign lesions. The combined assessment of C6orf15, P53, and Ki67 expressions may be beneficial in determining the grade of gastric dysplasia and evaluating the risk of progression in gastric mucosal lesions in clinical practice.