SG2NA enhances cancer cell survival by stabilizing DJ-1 and thus activating Akt

Area of Science:

• Cell Biology
• Molecular Biology
• Cancer Research

Background:

• SG2NA is a member of the striatin family of WD-40 repeat proteins, acting as a scaffold and phosphatase 2A regulatory subunit.
• SG2NA evolved early in metazoan evolution and produces various isoforms via alternative splicing.
• SG2NA protects neuronal cells from oxidative stress by recruiting DJ-1 and Akt to cellular compartments.

Purpose of the Study:

• To investigate the role of SG2NA in protecting DJ-1 from proteasomal degradation in cancer cells.
• To determine the effect of SG2NA downregulation on cancer cell growth and survival.
• To elucidate the mechanism by which reactive oxygen species influence SG2NA, DJ-1, and Akt interactions.

Main Methods:

• Investigated SG2NA's role in DJ-1 proteasomal degradation using cancer cell models.
• Assessed the impact of SG2NA downregulation on anchorage-dependent and independent cancer cell growth.
• Examined the effect of reactive oxygen species and N-acetyl-cysteine on SG2NA, DJ-1, and Akt trimerization.

Main Results:

• SG2NA was found to protect DJ-1 from proteasomal degradation in cancer cells.
• Downregulation of SG2NA led to reduced DJ-1/Akt colocalization, inhibiting cancer cell proliferation.
• Reactive oxygen species promote SG2NA, DJ-1, and Akt trimerization, while N-acetyl-cysteine reduces this effect and cancer cell growth.

Conclusions:

• SG2NA plays a crucial role in enhancing cancer cell survival by stabilizing DJ-1.
• Targeting SG2NA could be a viable strategy to impede cancer progression.
• Modulating reactive oxygen species levels offers a potential therapeutic approach to reduce cancer cell growth.