Gastric cancer (GC) is a prevalent and deadly malignancy of the digestive system, ranking among the world's most common tumors with high morbidity and mortality rates [1]. In China, approximately 64.7 % of patients receive a diagnosis at stage III or IV. Even in countries with comprehensive screening programs like Japan, nearly half of the patients are diagnosed at advanced stages of the disease [[2], [3], [4]]. The stark contrast in survival rates between early and advanced gastric cancer highlights the critical importance of early diagnosis and treatment [4,5]. Gastric epithelial dysplasia is recognized as both a precursor to carcinoma and a reliable marker of elevated cancer risk at the site where it is found. It is not only a precancerous lesion but also a dependable indicator of high cancer risk. Accurate diagnosis and classification of dysplasia are fundamental to endoscopic surveillance programs that aim for the early detection of gastrointestinal malignancies. The fifth edition of the World Health Organization (WHO) classification of tumors categorizes gastric epithelial dysplasia into high-grade dysplasia (HGD) and low-grade dysplasia (LGD) [6,7]. The diagnosis of gastric epithelial dysplasia is fraught with challenges, partly due to the significant heterogeneity in the appearance of each dysplasia grade. Moreover, the features characteristic of dysplasia are often only subtly different from those of regenerating epithelium, especially at the lower end of the spectrum, complicating this distinction [7]. If reliable immunohistochemical markers could aid in differential diagnosis, the clinical management of gastric dysplasia would become more precise and timely, potentially reducing the incidence and mortality rates of gastric cancer.

Chromosome 6 open reading frame 15 (C6orf15), also known as the simian taste bud-specific gene (STG), is located on the 6p21 region of the human chromosome [8]. The precise function of STG remains unclear, and information about this gene is limited. Chromosome 6 accounts for about 6 % of the human genome and includes genes that are directly associated with cancer, schizophrenia, autoimmune disorders, and other diseases [8,9]. Duplication of genetic material on the short (p) arm of chromosome 6 has been linked to the development and proliferation of several types of cancer [[10], [11], [12]]. Currently, research on the C6orf15 protein is focused on autoimmune and mental disorders, with only a single recent study reporting its association with the prognosis and metastasis of colorectal cancer [13]. We hypothesize that the expression of C6orf15 in gastric dysplasia and cancerous tissues may vary. Investigating the expression of C6orf15 in gastric dysplasia could provide a novel auxiliary marker for the diagnosis and differential diagnosis of this condition.