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Polymerase θ inhibition steps on the cGAS pedal.

ABSTRACT: Deficiencies in homologous recombination (HR) repair lead to an accumulation of DNA damage and can predispose individuals to cancer. Polymerase theta (Pol θ, encoded by POLQ) is overexpressed by HR-deficient cancers and promotes cancer cell survival by mediating error-prone double-stranded break (DSB) repair and facilitating resistance against poly-ADP ribose polymerase inhibitor treatment. In this issue of the JCI, Oh, Wang, et al. report on the impact of Pol θ inhibition on activation of antitumor immunity. The authors used pancreatic ductal adenocarcinoma (PDAC) cell and mouse models characterized by HR-associated gene alterations and POLQ overexpression. POLQ knockdown showed synthetic lethality in combination with gene mutations involving DNA repair, including BRCA1, BRCA2, and ATM. Notably, Pol θ deficiency or inhibition suppressed tumor growth, increased the accumulation of unrepaired DNA damage, and enhanced T cell infiltration via the cGAS/STING pathway. These findings suggest a broader scope for Pol θ inhibition in HR-deficient cancers.

SUBMITTER: Smith CM

PROVIDER: S-EPMC10231987 | biostudies-literature | 2023 Jun

REPOSITORIES: biostudies-literature

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Polymerase θ inhibition steps on the cGAS pedal.

Smith Chelsea M CM Gupta Gaorav P GP

The Journal of clinical investigation 20230601 11

Deficiencies in homologous recombination (HR) repair lead to an accumulation of DNA damage and can predispose individuals to cancer. Polymerase theta (Pol θ, encoded by POLQ) is overexpressed by HR-deficient cancers and promotes cancer cell survival by mediating error-prone double-stranded break (DSB) repair and facilitating resistance against poly-ADP ribose polymerase inhibitor treatment. In this issue of the JCI, Oh, Wang, et al. report on the impact of Pol θ inhibition on activation of antit ...[more]

PMID: 37259920

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