SOSTDC1 Nuclear Translocation Facilitates BTIC Maintenance and CHD1-Mediated HR Repair to Promote Tumor Progression and Olaparib Resistance in TNBC.
Adv Sci (Weinh)
; 11(29): e2306860, 2024 Aug.
Article
em En
| MEDLINE
| ID: mdl-38864559
ABSTRACT
Breast tumor-initiating cells (BTICs) of triple-negative breast cancer (TNBC) tissues actively repair DNA and are resistant to treatments including chemotherapy, radiotherapy, and targeted therapy. Herein, it is found that a previously reported secreted protein, sclerostin domain containing 1 (SOSTDC1), is abundantly expressed in BTICs of TNBC cells and positively correlated with a poor patient prognosis. SOSTDC1 knockdown impairs homologous recombination (HR) repair, BTIC maintenance, and sensitized bulk cells and BTICs to Olaparib. Mechanistically, following Olaparib treatment, SOSTDC1 translocates to the nucleus in an importin-α dependent manner. Nuclear SOSTDC1 interacts with the N-terminus of the nucleoprotein, chromatin helicase DNA-binding factor (CHD1), to promote HR repair and BTIC maintenance. Furthermore, nuclear SOSTDC1 bound to ß-transducin repeat-containing protein (ß-TrCP) binding motifs of CHD1 is found, thereby blocking the ß-TrCP-CHD1 interaction and inhibiting ß-TrCP-mediated CHD1 ubiquitination and degradation. Collectively, these findings identify a novel nuclear SOSTDC1 pathway in regulating HR repair and BTIC maintenance, providing insight into the TNBC therapeutic strategies.
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Texto completo:
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Base de dados:
MEDLINE
Assunto principal:
Ftalazinas
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Piperazinas
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Proteínas Adaptadoras de Transdução de Sinal
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Proteínas de Ligação a DNA
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Neoplasias de Mama Triplo Negativas
Limite:
Animals
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Female
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Humans
Idioma:
En
Ano de publicação:
2024
Tipo de documento:
Article