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The Role of Ras-Associated Protein 1 (Rap1) in Cancer: Bad Actor or Good Player?

ABSTRACT: Metastasis is known as the most life-threatening event in cancer patients. In principle, the immune system can prevent tumor development. However, dysfunctional T cells may fail to eliminate the tumor cells effectively and provide additional survival advantages for tumor proliferation and metastasis. Constitutive activation of Ras-associated protein1 (Rap1) has not only led to T cell anergy, but also inhibited autophagy and supported cancer progression through various oncogenic events. Inhibition of Rap1 activity with its negative regulator, Rap1GAP, impairs tumor progression. However, active Rap1 reduces tumor invasion in some cancers, indicating that the pleiotropic effects of Rap1 signaling in cancers could be cancer-specific. All in all, targeting Rap1 signaling and its regulators could potentially control carcinogenesis, metastasis, chemoresistance and immune evasion. Rap1GAP could be a promising therapeutic target in combating cancer.

SUBMITTER: Looi CK

PROVIDER: S-EPMC7555474 | biostudies-literature | 2020 Sep

REPOSITORIES: biostudies-literature

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The Role of Ras-Associated Protein 1 (Rap1) in Cancer: Bad Actor or Good Player?

Looi Chin-King CK Hii Ling-Wei LW Ngai Siew Ching SC Leong Chee-Onn CO Mai Chun-Wai CW

Biomedicines 20200907 9

Metastasis is known as the most life-threatening event in cancer patients. In principle, the immune system can prevent tumor development. However, dysfunctional T cells may fail to eliminate the tumor cells effectively and provide additional survival advantages for tumor proliferation and metastasis. Constitutive activation of Ras-associated protein1 (Rap1) has not only led to T cell anergy, but also inhibited autophagy and supported cancer progression through various oncogenic events. Inhibitio ...[more]

PMID: 32906721

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