Dual role of PID1 in regulating apoptosis induced by distinct anticancer-agents through AKT/Raf-1-dependent pathway...

Area of Science:

• Oncology
• Molecular Biology
• Biochemistry

Background:

• Hepatocellular carcinoma (HCC) treatment is challenging due to its complex etiology.
• Understanding genetic mechanisms of HCC response to anticancer agents is crucial for improving outcomes.
• Novel regulators of apoptosis and drug response in HCC require identification.

Purpose of the Study:

• To identify novel regulators of apoptosis and drug response in hepatocellular carcinoma (HCC).
• To investigate the role of Phosphotyrosine interaction domain-containing protein 1 (PID1) in modulating apoptosis and response to anticancer agents in HCC.
• To elucidate the molecular mechanisms by which PID1 affects chemotherapy and targeted therapy efficacy.

Main Methods:

• Cell-based assays to assess apoptosis, ROS production, and mitochondrial function.
• Protein interaction studies (e.g., co-immunoprecipitation) to identify binding partners of PID1.
• Western blotting and kinase assays to analyze signaling pathways (AKT, Raf-1, BRAF, ERK, MEK).
• In vivo studies using animal models to evaluate the effect of PID1 deficiency on treatment outcomes.

Main Results:

• PID1 was identified as a novel regulator of context-dependent apoptosis in HCC.
• PID1 inhibited chemotherapy-induced apoptosis by reducing ROS, mitochondrial dysfunction, and enhancing Raf-1-mediated BAD inhibition.
• PID1 altered Sorafenib's activity, leading to AKT blockade via the Raf-1/BRAF/ERK/MEK pathway.
• PID1 deficiency increased survival with Doxorubicin but reduced Sorafenib efficacy in vivo.
• PID1 acts as a biomarker for resistance to conventional chemotherapy and sensitivity to Sorafenib.

Conclusions:

• PID1 plays a dual role in HCC treatment response, conferring resistance to conventional chemotherapy while sensitizing to Sorafenib.
• PID1's interaction with PDPK1 and modulation of the AKT/Raf-1 pathway are key mechanisms underlying its effects.
• PID1 represents a potential predictive biomarker for stratifying HCC patients for specific therapeutic strategies.