Related Experiment Videos
Increased arylhydrocarbon receptor expression offers a potential therapeutic target for pancreatic cancer
Alexander Koliopanos1, Jörg Kleeff, Yi Xiao
1Department of Visceral and Transplantation Surgery, University of Bern, Inselspital, Switzerland.
Abstract:
The arylhydrocarbon receptor (AhR) was initially identified as a member of the adaptive metabolic and toxic response pathway to polycyclic aromatic hydrocarbons and to halogenated dibenzo-p-dioxins and dibenzofurans. In the present study, we sought to determine the functional significance of the AhR pathway in pancreatic carcinogenesis. AhR expression was analysed by Northern blotting. The exact site of AhR expression was analysed by in situ hybridization and immunohistochemistry. The effects of TCDD and four selective AhR agonists on pancreatic cancer cell lines were investigated by growth assays, apoptosis assays, and induction of the cyclin-dependent kinase inhibitor p21. There was strong AhR mRNA expression in 14 out of 15 pancreatic cancer samples, weak expression in chronic pancreatitis tissues, and faint expression in all normal pancreata. In pancreatic cancer tissues, AhR mRNA and protein expression were localized in the cytoplasm of pancreatic cancer cells. TCDD and the four AhR agonists inhibited pancreatic cancer cell growth in a dose-dependent manner, and decreased anchorage-independent cell growth. DAPI staining did not reveal nuclear fragmentation and CYP1A1 and was not induced by TCDD and AhR agonists. In contrast, TCDD and AhR agonists induced the expression of the cyclin-dependent kinase inhibitor p21. In conclusion, the relatively non-toxic AhR agonists caused growth inhibition in pancreatic cancer cells with high AhR expression levels via cell cycle arrest. In addition, almost all human pancreatic cancer tissues expressed this receptor at high levels, suggesting that these or related compounds may play a role in the therapy of pancreatic cancer in the future.
Insights
The aryl hydrocarbon receptor (AhR) is highly expressed in pancreatic cancer. AhR agonists inhibit cancer cell growth by inducing cell cycle arrest, suggesting potential therapeutic applications.
Area of Science:
- Molecular Biology
- Oncology
- Toxicology
Background:
- The aryl hydrocarbon receptor (AhR) pathway is involved in metabolic and toxic responses.
- Its role in pancreatic carcinogenesis remains largely unexplored.
Purpose of the Study:
- To investigate the functional significance of the AhR pathway in pancreatic cancer.
- To explore the therapeutic potential of AhR agonists in pancreatic cancer treatment.
Main Methods:
- Analyzed AhR expression in pancreatic tissues using Northern blotting, in situ hybridization, and immunohistochemistry.
- Treated pancreatic cancer cell lines with TCDD and AhR agonists, assessing growth, apoptosis, and p21 induction.
- Investigated effects on anchorage-independent growth and CYP1A1 induction.
Main Results:
- Strong AhR mRNA and protein expression were observed in most pancreatic cancer samples, with lower levels in chronic pancreatitis and normal tissues.
- AhR agonists inhibited pancreatic cancer cell growth and anchorage-independent growth in a dose-dependent manner.
- TCDD and AhR agonists induced the cyclin-dependent kinase inhibitor p21, leading to cell cycle arrest, but did not induce CYP1A1.
Conclusions:
- High AhR expression in pancreatic cancer suggests its involvement in the disease.
- AhR agonists can inhibit pancreatic cancer cell growth via cell cycle arrest.
- AhR agonists represent a potential therapeutic strategy for pancreatic cancer.