Doublecortin-like kinase 1 compromises DNA repair and induces chromosomal instability

Area of Science:

• Cell Biology
• Molecular Oncology
• Cancer Stem Cell Biology

Background:

• Doublecortin-like kinase 1 (DCLK1) is a serine/threonine-kinase implicated in cancer stem cell function and tumor aggressiveness.
• Clinical evidence links DCLK1 to poor prognosis across various human cancers.
• The precise oncogenic mechanisms of DCLK1 remain largely unknown.

Purpose of the Study:

• To elucidate the molecular mechanisms by which DCLK1 contributes to oncogenesis.
• To investigate the role of DCLK1 in cellular processes related to tumor initiation and progression.
• To determine if DCLK1's kinase activity or microtubule association is essential for its oncogenic functions.

Main Methods:

• Utilized human mammary epithelial MCF10A cells to assess sphere formation capacity.
• Employed human colon cancer HCT116 and lung cancer H1299 cell lines to evaluate DNA repair.
• Generated and tested kinase-negative and microtubule-binding deficient DCLK1 mutants.

Main Results:

• DCLK1 expression enabled MCF10A cells to form spheres, mimicking stem cell-like behavior.
• DCLK1 was found to induce chromatin instability in MCF10A cells.
• DCLK1 impaired DNA repair mechanisms in HCT116 and H1299 cancer cells.
• Mutants lacking kinase activity or microtubule association still compromised DNA repair.

Conclusions:

• DCLK1 promotes tumorigenesis by inducing genomic instability through interference with DNA repair.
• This DCLK1-mediated oncogenic function is independent of its kinase activity and microtubule-binding ability.
• DCLK1 represents a potential therapeutic target for cancers driven by genomic instability.