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HEATR1 deficiency promotes pancreatic cancer proliferation and gemcitabine resistance by up-regulating Nrf2 signaling.

ABSTRACT: The human HEAT repeat-containing protein 1 (HEATR1), consisting of 2144 amino acids, is a member of the UTP10 family and contains one HEAT repeat at its C-terminal. HEATR1 has been reported to regulate cytotoxic T lymphocytes and rRNA synthesis, while its functions in tumors are poorly understood. Here, we found that HEATR1 competed with Keap1 for binding to p62/sequestosome 1 (SQSTM1), resulted in up-regulation of Keap1, which then inhibited Nrf2 signaling in pancreatic cancer cells. HEATR1 knockdown enhanced proliferation and gemcitabine resistance of pancreatic cancer cells. Moreover, HEATR1 deficiency significantly improved xenografts growth and led to gemcitabine resistance in pancreatic cancer cell-derived xenografts through up-regulating Nrf2 signaling. By analyzing tumor tissue samples from pancreatic cancer patients, we found that low expression of HEATR1 was closely correlated with poor prognosis and clinicopathological features. Collectively, we suggest that HEATR1 deficiency promotes proliferation and gemcitabine resistance of pancreatic cancer through up-regulating Nrf2 signaling, indicating that HEATR1 may be a promising therapeutic target for pancreatic cancer.

SUBMITTER: Zhou Y

PROVIDER: S-EPMC6888747 | biostudies-literature | 2020 Jan

REPOSITORIES: biostudies-literature

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HEATR1 deficiency promotes pancreatic cancer proliferation and gemcitabine resistance by up-regulating Nrf2 signaling.

Zhou Yunjiang Y Wang Keke K Zhou Yang Y Li Tao T Yang Mengdi M Wang Rui R Chen Yaxin Y Cao Mengran M Hu Rong R

Redox biology 20191120

The human HEAT repeat-containing protein 1 (HEATR1), consisting of 2144 amino acids, is a member of the UTP10 family and contains one HEAT repeat at its C-terminal. HEATR1 has been reported to regulate cytotoxic T lymphocytes and rRNA synthesis, while its functions in tumors are poorly understood. Here, we found that HEATR1 competed with Keap1 for binding to p62/sequestosome 1 (SQSTM1), resulted in up-regulation of Keap1, which then inhibited Nrf2 signaling in pancreatic cancer cells. HEATR1 kno ...[more]

PMID: 31785531

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HEATR1 deficiency promotes pancreatic cancer proliferation and gemcitabine resistance by up-regulating Nrf2 signaling.

Publications

HEATR1 deficiency promotes pancreatic cancer proliferation and gemcitabine resistance by up-regulating Nrf2 signaling.

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