Background And Aims: Chemoresistance is a major challenge in pancreatic cancer (PC) treatment. Limited data have shown that members of the Notch signaling pathway are involved in resistance to gemcitabine (GEM) in PC. However, further evidence is needed and the underlying mechanisms remain to be elucidated. The current study aims to investigate the role of alterations of the intrinsic apoptosis pathway in Notch-induced GEM resistance of PC.

Methods: The Notch signaling pathway was inhibited or activated in three PC cell lines (AsPC-1, BxPC-3, and MIA PaCa-2) by γ-secretase inhibition and Notch intracellular domain (NICD) overexpression, respectively. Subsequent analyses included inhibition rates of cell proliferation by GEM, cell apoptosis, and expression of proteins involved in the intrinsic apoptosis pathway.

Results: Hes-1 expression was significantly elevated after GEM treatment, indicating Notch activation. Inhibition of the Notch signaling pathway by DAPT, a γ-secretase inhibitor, resulted in a significant increase of the inhibition rates by GEM in all PC cell lines. In addition, there was more frequent apoptosis, higher caspase-3 activity, up-regulation of Bax, and down-regulation of Bcl-2 and Bcl-xL. Conversely, transient transfection of NICD, which enhances the activity of the Notch signaling, caused a remarkable decrease of the chemosensitivity to GEM.

Conclusions: An alteration of the intrinsic apoptosis pathway is involved in Notch-induced chemoresistance to GEM in PC cells.

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.arcmed.2013.10.001DOI Listing

Publication Analysis

Top Keywords

intrinsic apoptosis
16
notch signaling
16
apoptosis pathway
12
pathway involved
12
signaling pathway
12
alteration intrinsic
8
involved notch-induced
8
notch-induced chemoresistance
8
pancreatic cancer
8
cell lines
8

Similar Publications

Background: Breast cancer is the most common cancer among women worldwide, impacting not only the patients but also their families and communities. vent. is a plant endemic to Mexico, traditionally used in Zapotec medicine for the treatment of cancer.

View Article and Find Full Text PDF

Hearing loss is a pervasive issue affecting numerous individuals, and its etiology and categorization are multifaceted. Among these, sensorineural hearing loss (SNHL) emerges as the most prevalent variant among these. The primary causative factor underlying SNHL resides in the depletion of auditory hair cells within the cochlea, yet the pursuit of efficacious therapeutic interventions remains an ongoing challenge.

View Article and Find Full Text PDF

Effects of ocean acidification and warming on apoptosis and immune response in the mussel Mytilus coruscus.

Fish Shellfish Immunol

January 2025

International Research Center for Marine Biosciences, Ministry of Science and Technology, Shanghai Ocean University, Shanghai 201306, China; Marine Biomedical Science and Technology Innovation Platform of Lin-gang Special Area, Shanghai 201306, China. Electronic address:

Ocean acidification and warming are significant stressors impacting marine ecosystems, exerting profound effects on the physiological ecology of marine organisms. We investigated the impact of ocean acidification and warming on the immune system of mussels, focusing on the regulatory mechanisms of intrinsic and extrinsic apoptosis. The study explored the effects on the immune response ability of mussels (Mytilus coruscus) after 14 and 21 days under combined conditions of different temperatures (20 °C and 30 °C) and pH (8.

View Article and Find Full Text PDF

Advanced oxidation protein products induce apoptosis in thyroid follicular epithelial cells through oxidative stress in Hashimoto's thyroiditis.

Int Immunopharmacol

January 2025

Department of General Surgery & Guangdong Provincial Key Laboratory of Precision Medicine for Gastrointestinal Tumor, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, China. Electronic address:

Hashimoto's thyroiditis (HT) is a chronic autoimmune disorder primarily driven by T cell. The apoptosis of the follicular thyroid cells plays an important role in HT apart from the lymphocyte-mediated cytotoxicity. Advanced oxidation protein products (AOPPs), resulting from oxidative stress, are known to be involved in various inflammatory diseases.

View Article and Find Full Text PDF

Background: Pancreatic ductal adenocarcinoma (PDAC) is mostly refractory to immunotherapy due to immunosuppression in the tumor microenvironment and cancer cell-intrinsic T cell tolerance mechanisms. PDAC is described as a "cold" tumor type with poor infiltration by T cells and factors leading to intratumoral T cell suppression have thus received less attention. Here, we identify a cancer cell-intrinsic mechanism that contributes to a T cell-resistant phenotype and describes potential combinatorial therapy.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!