Minichromosome maintenance 4 is associated with poor survival and stemness of patients with pancreatic cancer.

Pancreatic ductal adenocarcinoma (PDAC) is one of the most well-known cancer types, with a persistently poor 5-year survival rate. We previously reported MCM4 as a molecule associated with cancer stem cells; however, its role in PDAC has not been reported. Therefore, in this study, we aimed to fill this gap in the literature. We analyzed MCM4 expression in 81 PDAC samples using immunohistochemistry (IHC). The functional role of MCM4 in PDAC was investigated using RNA interference in PDAC cell lines. Additionally, a single-cell analysis was conducted by downloading data from six PDAC cases. On IHC, high MCM4 expression was observed in 42 out of 81 (51.9%) PDAC cases. MCM4-positive PDAC was significantly associated with a higher pN grade. Furthermore, high MCM4 expression was linked to a significantly poorer prognosis and was identified as an independent prognostic factor in multivariate analysis. In PDAC cell lines, MCM4 knockdown impairs cell growth and spheroid formation. Single-cell analysis also revealed that MCM4-expressing cells were located upstream of the trajectory, with a cluster showing a correlation with KIFC1, which has been reported to be associated with cancer stemness. These results indicated the significance of MCM4 expression in PDAC and its association with cancer stemness.