CRISPR/Cas9-mediated knockout of PIM3 suppresses tumorigenesis and cancer cell stemness in human hepatoblastoma cells.

ABSTRACT: Hepatoblastoma remains one of the most difficult childhood tumors to treat and is alarmingly understudied. Over half of patients initially present with locally advanced or metastatic disease and the prognosis for this cohort remains dismal. In addition, many of these children have disease that is resistant to standard therapies and will require novel and targeted therapies to effectively treat or manage their disease. We previously demonstrated that Proviral Insertion site in Maloney murine leukemia virus (PIM) kinases, specifically PIM3, are overexpressed in human hepatoblastoma cells and function to promote tumorigenesis. We aimed to use CRISPR/Cas9 gene editing technology with dual gRNAs to introduce large inactivating deletions in the PIM3 gene and achieve stable PIM3 knockout (KO) in the human hepatoblastoma cell line, HuH6. PIM3 KO of hepatoblastoma cells led to significantly decreased proliferation, viability, and motility, inhibited cell-cycle progression, decreased tumor growth in a xenograft murine model, and increased animal survival. Analysis of RNA sequencing data revealed that PIM3 KO downregulated expression of pro-migratory and pro-invasive genes and upregulated expression of genes involved in apoptosis and differentiation. Furthermore, PIM3 KO decreased hepatoblastoma cancer cell stemness as evidenced by decreased tumorsphere formation, decreased mRNA abundance of stemness markers, and decreased cell surface expression of CD133, a marker of hepatoblastoma stem cell-like cancer cells. Reintroduction of PIM3 into PIM3 KO cells rescued the malignant phenotype. These findings emphasize the role of PIM3 in promoting hepatoblastoma tumorigenesis and provide evidence that targeting PIM3 may offer a novel therapeutic approach for children with hepatoblastoma.

ORGANISM(S): Homo sapiens

PROVIDER: GSE164082 | GEO | 2021/10/27

REPOSITORIES: GEO