Background: The Dickkopf (DKK) family comprises a set of proteins that function as regulators of Wnt/beta-catenin signaling and has a crucial role in development. Recent studies have revealed the involvement of this family in tumorigenesis, however their role in tumorigenesis is still remained unclear.
Methodology/principal Findings: We found increased expression of DKK2 but decreased expression of DKK1 in Ewing family tumor (EFT) cells. We showed that EFT-specific EWS/ETS fusion proteins enhance the DKK2 promoter activity, but not DKK1 promoter activity, via ets binding sites (EBSs) in the 5' upstream region. EWS/ETS-mediated transactivation of the promoter was suppressed by the deletion and mutation of EBSs located upstream of the DKK2 gene. Interestingly, the inducible expression of EWS/ETS resulted in the strong induction of DKK2 expression and inhibition of DKK1 expression in human primary mesenchymal progenitor cells that are thought to be a candidate of cell origin of EFT. In addition, using an EFT cell line SK-ES1 cells, we also demonstrated that the expression of DKK1 and DKK2 is mutually exclusive, and the ectopic expression of DKK1, but not DKK2, resulted in the suppression of tumor growth in immuno-deficient mice.
Conclusions/significance: Our results suggested that DKK2 could not functionally substitute for DKK1 tumor-suppressive effect in EFT. Given the mutually exclusive expression of DKK1 and DKK2, EWS/ETS regulates the transcription of the DKK family, and the EWS/ETS-mediated DKK2 up-regulation could affect the tumorigenicity of EFT in an indirect manner.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2644785 | PMC |
http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0004634 | PLOS |
Curr Oncol
January 2025
Energy & Memory, Brain Plasticity Unit, CNRS, ESPCI Paris, PSL Research University, 75006 Paris, France.
(1) Background: Hepatoblastoma and medulloblastoma are two types of pediatric tumors with embryonic origins. Both tumor types can exhibit genetic alterations that affect the β-catenin and Wnt pathways; (2) Materials and Methods: This study used bioinformatics and integrative analysis of multi-omics data at both the tumor and single-cell levels to investigate two distinct pediatric tumors: medulloblastoma and hepatoblastoma; (3) Results: The cross-transcriptome analysis revealed a commonly regulated expression signature between hepatoblastoma and medulloblastoma tumors. Among the commonly upregulated genes, the transcription factor LEF1 was significantly expressed in both tumor types.
View Article and Find Full Text PDFBreast Cancer Res
January 2025
Department of Cancer Biology, Loyola University Chicago Stritch School of Medicine, Maywood, IL, 50153, USA.
Resistance to endocrine therapies remains a major clinical hurdle in breast cancer. Mutations to estrogen receptor alpha (ERα) arise after continued therapeutic pressure. Next generation selective estrogen receptor modulators and degraders/downregulators (SERMs and SERDs) show clinical efficacy, but responses are often non-durable.
View Article and Find Full Text PDFEndocrinology
January 2025
Anne M. Delany, PhD, Center for Molecular Oncology, UConn Health, Farmington, CT.
Glucocorticoid excess causes bone loss due to decreased bone formation and increased bone resorption; miR-433-3p is a miRNA that negatively regulates bone formation in male mice by targeting Runx2 as well as RNAs involved in Wnt, protein kinase A and endogenous glucocorticoid signaling. To examine the impact of miR-433-3p on glucocorticoid-mediated bone loss, transgenic mice expressing a miR-433-3p tough decoy inhibitor in the osteoblast lineage were administered prednisolone via slow-release pellets. Bone loss was greater in control mice treated with prednisolone compared with miR-433-3p tough decoy mice due to higher osteoclast activity in the controls.
View Article and Find Full Text PDFSci Rep
January 2025
Department of Medical Physiology, Texas A&M College of Medicine, Bryan, TX, 77807, USA.
Osteosarcoma (OS) is the most common primary bone malignancy. The canonical Wnt inhibitor Dickkopf-1 (Dkk-1) has been implicated in bone destruction, tumor survival and metastases during OS. We examined the role of Dkk-1 in OS disease progression and explored strategies for targeting its activity.
View Article and Find Full Text PDFCell Death Dis
January 2025
The First Affiliated Hospital, Cancer Research Institute, Hengyang Medical School, University of South China, Hengyang, Hunan, 421001, PR China.
This research demonstrates that DCC-2036 (Rebastinib), a potent third-generation tyrosine kinase inhibitor (TKI), effectively suppresses tumor growth in colorectal cancer (CRC) models with functional immune systems. The findings underscore the capacity of DCC-2036 to enhance both the activation and cytotoxic functionality of CD8 T cells, which are crucial for facilitating anti-tumor immune responses. Through comprehensive multi-omics investigations, significant shifts in both gene and protein expression profiles were detected, notably a marked decrease in DKK1 levels.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!