Targeting OGG1 arrests cancer cell proliferation by inducing replication stress

Area of Science:

• Oncology
• Molecular Biology
• DNA Repair

Background:

• Cancer cells exhibit altered oncogene expression, leading to redox imbalance and oxidative DNA damage like 8-oxoguanine (8-oxoG).
• Base excision repair (BER) pathway, coordinated by PARP1, repairs 8-oxoG, with 8-oxoguanine-DNA glycosylase (OGG1) initiating the process by recognizing and excising 8-oxoG.

Purpose of the Study:

• To investigate OGG1 as a potential therapeutic target for exploiting elevated reactive oxygen species (ROS) in cancer.
• To validate the efficacy of OGG1 inhibition in treating T-cell lymphoblastic acute leukemia and other cancer types.

Main Methods:

• Depletion of OGG1 using shRNA in cancer cell lines and in vivo models.
• Treatment of various cancer cells with OGG1 inhibitors (OGG1i).
• Assessment of DNA damage, replication stress, proliferation, and cell death.

Main Results:

• OGG1 depletion significantly inhibited the growth of A3 T-cell lymphoblastic acute leukemia in vitro and in vivo.
• OGG1 inhibitors demonstrated efficacy against a broad spectrum of cancer cells.
• OGG1 inhibition resulted in S-phase DNA damage, replication stress, proliferation arrest, and/or cell death.

Conclusions:

• OGG1 is a validated anti-cancer target, particularly effective in T-cell lymphoblastic acute leukemia.
• OGG1 inhibitors offer a novel therapeutic strategy by inducing DNA damage and replication stress in cancer cells.
• This study positions OGG1 alongside PARP1 as a key BER factor targetable for cancer treatment.