No abstract

Pancreatic ductal adenocarcinoma (PDAC) is a common malignancy that shows high cancer-mortality and poor prognosis, in the absence of obvious symptoms and biomarkers for early diagnosis. Gemcitabine is a type of chemotherapy drug which commonly used to treat PDAC, however, the rapid acquisition of resistance to gemcitabine treatment has been observed in many of PDAC patients. The miRNA-producing enzymes Dicer is crucial for the maturation of miRNAs, and we found previously that ERK/Sp1 signaling transactivate both gene and protein expressions of Dicer, leading an acquisition of gemcitabine resistance in pancreatic cancer cells both in vitro and in vivo. In this study, we further identified that phosphomimetic S1016E of Dicer may regulate miRNAs maturation, resulting an imbalance of glutaminase (GLS) and glutamine synthetase (GS/GLUL). Metabolism analysis revealed that gemcitabine-resistant PANC-1 (PANC-1/GEM) cells have high glutamine dependence and GLS/GLUL ratio. Our study suggests that phosphomimetic Dicer S1016E plays a critical role in glutamine metabolism reprogramming and gemcitabine resistance of pancreatic cancer. Citation Format: Ching-Feng Chiu, Ji Min Park, Yu-Shiuan Shen, Chia-Ying Lin, Tung-Wei Hsu, Yen-Hao Su, Hsin-An Chen. Phosphomimetic Dicer rewires glutamine metabolism and gemcitabine resistance in pancreatic ductal adenocarcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 6386.