In patient‐derived xenograft (PDX) models with high or low expression of DBH‐AS1, when cancer growth in the presence of gemcitabine was examined, the growth rate was higher in the group with low expression of DBH‐AS1, suggesting that DBH‐AS1 is associated with USP44‐mediated cancer growth and gemcitabine resistance. Here, USP44 is linked to cancer.