ZIP4 Increases Expression of Transcription Factor ZEB1 to Promote Integrin α3β1 Signaling and Inhibit Expression of...

Area of Science:

• Oncology
• Molecular Biology
• Biochemistry

Background:

• Pancreatic tumors exhibit rapid growth, chemoresistance, and postsurgical recurrence.
• The solute carrier family 39 member 4 (SLC39A4, or ZIP4) protein regulates intracellular zinc and is upregulated in pancreatic cancer.

Purpose of the Study:

• To investigate the role of ZIP4 in pancreatic cancer progression and chemotherapy resistance.
• To elucidate the molecular mechanisms by which ZIP4 influences tumor growth and drug sensitivity.

Main Methods:

• Analysis of 93 pancreatic cancer specimens using immunohistochemistry.
• Overexpression and knockdown of ZIP4, ITGA3, ITGB1, and ZEB1 in pancreatic cancer cell lines and mouse models.
• Assessment of gemcitabine sensitivity, tumor growth, metastasis, and molecular signaling pathways (JNK, ENT1).

Main Results:

• Increased ZIP4 levels correlated with shorter survival in patients.
• ZIP4 overexpression conferred resistance to gemcitabine, 5-fluorouracil, and cisplatin, while ZIP4 knockdown increased sensitivity.
• ZIP4 upregulates ZEB1, ITGA3, and ITGB1, leading to integrin α3β1 signaling, JNK activation, and inhibition of the gemcitabine transporter ENT1, reducing drug uptake.

Conclusions:

• ZIP4 promotes pancreatic cancer growth and chemoresistance by activating the ZEB1/ITGA3/ITGB1/JNK pathway.
• This pathway inhibits ENT1 expression, decreasing gemcitabine accumulation in cancer cells.
• Targeting this ZIP4-mediated pathway may offer therapeutic strategies for pancreatic cancer.