APE1 Promotes Pancreatic Cancer Proliferation through GFRα1/Src/ERK Axis-Cascade Signaling in Response to GDNF

Area of Science:

• Oncology
• Molecular Biology
• Biochemistry

Background:

• Pancreatic cancer exhibits high mortality, with aberrant apurinic/apyrimidinic endodeoxyribonuclease 1 (APE1) linked to uncontrolled cell growth.
• The precise molecular mechanisms of APE1's role in pancreatic cancer progression are not fully understood.

Purpose of the Study:

• To elucidate the molecular mechanism by which APE1 contributes to pancreatic cancer cell proliferation.
• To investigate the involvement of the glial cell line-derived neurotrophic factor (GDNF)/glial factor receptor α1 (GFRα1)/Src/ERK signaling cascade.

Main Methods:

• Utilized MIA PaCa-2 human pancreatic carcinoma cells with endogenous APE1 expression.
• Employed small interference RNA (siRNA) to downregulate APE1 and GFRα1 expression.
• Administered GDNF and the MEK-1 inhibitor PD98059.
• Assessed cell proliferation, Src inactivation, and ERK phosphorylation.
• Examined APE1 and GFRα1 expression levels in relation to pancreatic cancer grades.

Main Results:

• GDNF treatment increased proliferation in APE1-expressing MIA PaCa-2 cells.
• Downregulation of APE1 or GFRα1 inhibited GDNF-induced proliferation.
• PD98059 treatment decreased GDNF-induced proliferation.
• Src inactivation reduced ERK phosphorylation in response to GDNF.
• Overexpression of GFRα1 in APE1-deficient cells activated Src and ERK phosphorylation.
• Both APE1 and GFRα1 expression increased with pancreatic cancer grade progression.

Conclusions:

• APE1 critically promotes pancreatic cancer cell proliferation through the GDNF/GFRα1/Src/ERK signaling axis.
• This pathway represents a potential therapeutic target for pancreatic cancer treatment.