Hsp-27 and NF-κB pathway is associated with AR/AR-V7 expression in prostate cancer cells

Area of Science:

• Oncology
• Molecular Biology
• Cell Signaling

Background:

• Prostate cancer progression is linked to androgen receptor (AR) signaling.
• AR variants, such as AR-V7, contribute to treatment resistance.
• NF-κB and Heat Shock Protein 27 (Hsp-27) pathways are implicated in cancer cell survival and AR expression.

Purpose of the Study:

• To investigate the molecular mechanisms of AR expression regulation in prostate cancer cells.
• To explore the role of NF-κB and Hsp-27 inhibition in modulating AR signaling.
• To assess the potential of combined therapeutic strategies involving NF-κB, Hsp-27, and AR-V7 inhibition.

Main Methods:

• Utilized NF-κB inhibitor BAY 11-7082 and Hsp-27 inhibitor KRIBB-3 in LNCaP and 22Rv1 prostate cancer cell lines.
• Administered siRNA targeting AR-V7 in 22Rv1 cells.
• Analyzed protein expression levels of AR, p65, p-IKK α/β, p-Hsp-27, Noxa, and Bcl-2.
• Evaluated phosphorylation status of key signaling proteins.

Main Results:

• Inhibition of NF-κB and Hsp-27 led to decreased AR and p65 expression, particularly after 48 hours in LNCaP cells, correlating with reduced p-IKK α/β and p-Hsp-27.
• Combined treatment with NF-κB and Hsp-27 inhibitors, as well as AR-V7 siRNA, significantly reduced AR-V7, AR, and p65 expression in 22Rv1 cells.
• The combination therapy induced apoptosis, evidenced by increased Noxa and decreased Bcl-2 protein levels.

Conclusions:

• NF-κB and Hsp-27 signaling pathways play a significant role in regulating AR expression and are involved in AR variant formation.
• Combined inhibition of NF-κB, Hsp-27, and AR-V7 demonstrates therapeutic potential by inducing apoptosis in prostate cancer cells.
• Targeting NF-κB and Hsp-27 is a promising strategy to enhance therapies aimed at AR-V7 inhibition in prostate cancer treatment.