Association Between Glucose-related Protein 94 (GRP94) and Colorectal Cancer Location.

Background: The incidence of chemotherapy-resistant colorectal cancer (CRC) is increasing. Location of CRC is important in determining CRC progression. The location itself is associated with the presence of cancer stem cell. Objective: The aim of this study is to determine association between GRP94 expression, a cancer stem cell marker, and location of CRC. Methods: This cross-sectional study was conducted in Adam Malik Hospital and it's sister hospitals. Inclusion criteria were patients who underwent colonoscopy or biopsy or operation due to CRC, Indonesian and willing to provide familial medical history regarding CRC and other malignancies up to third degree relatives. CRC tissue was obtained from each subject as specimen and undergone immunohistochemistry examination to determine GRP94 expression. Data was analyzed using statistical software. Results: A total of 118 subjects were involved and divided into proximal (32 subjects), distal (43 subjects), and rectal (43 subjects) CRC. Mean age of subjects was 57.30 (SD 12.99) years with 69 (58.5%) subjects were males. The percentage of high level GRP94 expression was found in subjects with distal CRC, folllowed by proximal and rectal CRC. There was a significant association between GRP94 expression and location of CRC (p=0.007). No relationship was observed between GRP94 expression with gender, age, body mass index, hemoglobin level, leukocyte count, platelet count, and histopathology grade of CRC. Conclusion: GRP94C expression is associated with the location of CRC. Higher GRP94 expression is observed in distal CRC.