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Nuclear receptor coactivator RAC3 inhibits autophagy.

ABSTRACT: RAC3 is an oncogene naturally overexpressed in several tumors. Besides its role as coactivator, it can exert several protumoral cytoplasmic actions. Autophagy was found to act either as a tumor suppressor during the early stages of tumor development, or as a protector of the tumor cell in later stages under hypoxic conditions. We found that RAC3 overexpression inhibits autophagy when induced by starvation or rapamycin and involves RAC3 nuclear translocation-dependent and -independent mechanisms. Moreover, hypoxia inhibits the RAC3 gene expression leading to the autophagy process, allowing tumor cells to survive until angiogenesis occurs. The interplay between RAC3, hypoxia, and autophagy could be an important mechanism for tumor progression and a good target for a future anticancer therapy.

SUBMITTER: Fernandez Larrosa PN

PROVIDER: S-EPMC7659320 | biostudies-literature | 2012 Dec

REPOSITORIES: biostudies-literature

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Nuclear receptor coactivator RAC3 inhibits autophagy.

Fernandez Larrosa Pablo Nicolas PN Alvarado Cecilia Viviana CV Rubio Maria Fernanda MF Ruiz Grecco Marina M Micenmacher Sabrina S Martinez-Noel Giselle Astrid GA Panelo Laura L Costas Monica Alejandra MA

Cancer science 20121022 12

RAC3 is an oncogene naturally overexpressed in several tumors. Besides its role as coactivator, it can exert several protumoral cytoplasmic actions. Autophagy was found to act either as a tumor suppressor during the early stages of tumor development, or as a protector of the tumor cell in later stages under hypoxic conditions. We found that RAC3 overexpression inhibits autophagy when induced by starvation or rapamycin and involves RAC3 nuclear translocation-dependent and -independent mechanisms. ...[more]

PMID: 22957814

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