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Interaction and global proteomics reveal the role of the pluripotency factor L1TD1 in embryonal tumor cell proliferation and mobility

ABSTRACT: Pluripotency factors are known to be abnormally expressed cancer cells, which often correlate with poor prognosis. The molecular mechanisms by which pluripotency factors contribute to tumor aggressiveness are yet to be elucidated. The pluripotency marker L1TD1 interacts with other pluripotency factors and is a marker for human embryonic stem cells. In cancer, L1TD1 expression has been detected in solid tumors, including Embryonal tumors of the Central Nervous System. Previously, we reported that, in medulloblastoma, L1TD1 expression correlates with metastasis and shorter overall patient survival. Here, we use Affinity purification-mass spectrometry and global proteomics to map the L1TD1 protein interaction network and assess proteins regulated by L1TD1 expression, respectively. Interactome and global proteome analysis led to the enrichment of overlapping Biological Processes attributed to L1TD1 including Cell proliferation, Cell death and cell migration. We also used L1TD1 overexpressing tumor cell populations for in vitro validation of the omic data. L1TD1 overexpressing cells presented higher cell mobility, enhanced filopodial formation and distinct cell morphology. These cells were overall more proliferative and resistant to cisplatin treatment in vitro.

INSTRUMENT(S): Orbitrap Fusion

DISEASE(S): Medulloblastoma

SUBMITTER: Brandon Coke

LAB HEAD: Rob Ewing

PROVIDER: PXD040803 | Pride | 2024-02-09

REPOSITORIES: Pride

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Interaction and global proteomics reveal the role of the pluripotency factor L1TD1 in embryonal tumor cell proliferation and mobility

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