Gemcitabine-loaded chitosan nanoparticles enhanced apoptotic and ferroptotic response of gemcitabine treatment alone in the pancreatic cancer cells in vitro.

Gemcitabine (GEM) is a first-line treatment for pancreatic ductal adenocarcinoma (PDAC) patients, causing side effects and poor overall survival. Eighty percent of patients often develop resistance rapidly to GEM. Developing therapeutic approaches and increasing sensitivity to gemcitabine in PDAC has become one of the challenges in cancer research. We synthesized GEM-loaded NPs prepared with a method that combines ultrasonication and ionotropic gelation to overcome GEM-related limitations in PDAC. CFPAC-1 cells were treated with increased concentrations of GEM, empty chitosan, and GEM-loaded NPs (0.66, 1.32, 2.64, 5.32 µg/ml) for up to 48 h. Empty chitosan NPs did not show toxicity on L929 cells. Antioxidant enzyme activities, including glucose 6-phosphate dehydrogenase (G6PD), 6-phosphogluconate dehydrogenase (6-PGD), glutathione reductase (GR), glutathione s-transferase (GST), and glutathione peroxidase (GPx), significantly reduced in GEM-loaded NPs compared to the GEM associated with increased oxidative stress, PPP, and glycolysis. Bcl-xL, NOXA/mcl-1, and Ca2+ levels significantly increased in GEM-loaded NP-administered cells compared to the GEM and control groups. In contrast, JNK, p38, STAT3, Akt, and CREB levels significantly decreased in the GEM-loaded NP group, addressing enhanced apoptotic response compared to the GEM alone. Increased ferroptosis activity in GEM-loaded NP-administered groups has been validated via decreased antioxidant enzyme activities, increased cytosolic Fe, Zn, Mg, and Mn levels, and reduced GPx activity compared to the GEM and control groups. For the first time in the literature, we showed biocompatible GEM-loaded NPs enhanced apoptotic and ferroptotic response in CFPAC-1 cells via downregulation of antioxidant, glycolysis, and PPP metabolism compared to the GEM alone.