CASZ1, a candidate tumor-suppressor gene, suppresses neuroblastoma tumor growth through reprogramming gene expression
1Pediatric Oncology Branch, Center for Cancer Research, National Cancer Institute, Bethesda, MD, USA.
Abstract:
Neuroblastoma (NB) is a common childhood malignant tumor of the neural crest-derived sympathetic nervous system. In NB the frequent loss of heterozygosity (LOH) on chromosome 1p raises the possibility that this region contains tumor-suppressor genes whose inactivation contributes to tumorigenesis. The human homolog of the Drosophila neural fate determination gene CASZ1, a zinc-finger transcription factor, maps to chromosome 1p36.22, a region implicated in NB tumorigenesis. Quantitative real-time PCR analysis showed that low-CASZ1 expression is significantly correlated with increased age (≥18 months), Children's Oncology Group high-risk classification, 1p LOH and MYCN amplification (all P<0.0002) and decreased survival probability (P=0.0009). CASZ1 was more highly expressed in NB with a differentiated histopathology (P<0.0001). Retinoids and epigenetic modification agents associated with regulation of differentiation induced CASZ1 expression. Expression profiling analysis revealed that CASZ1 regulates the expression of genes involved in regulation of cell growth and developmental processes. Specific restoration of CASZ1 in NB cells induced cell differentiation, enhanced cell adhesion, inhibited migration and suppressed tumorigenicity. These data are consistent with CASZ1 being a critical modulator of neural cell development, and that somatically acquired disruption of normal CASZ1 expression contributes to the malignant phenotype of human NB.
Insights
The CASZ1 gene acts as a tumor suppressor in neuroblastoma (NB), a common childhood cancer. Restoring CASZ1 expression promotes cell differentiation and inhibits tumor growth, offering potential therapeutic strategies.
Area of Science:
- Molecular Oncology
- Developmental Biology
- Pediatric Cancer Research
Background:
- Neuroblastoma (NB) is a malignant tumor arising from neural crest cells.
- Loss of heterozygosity on chromosome 1p in NB suggests the presence of tumor suppressor genes.
- CASZ1, a gene on chromosome 1p36.22, is a homolog of a Drosophila neural fate determination gene.
Purpose of the Study:
- To investigate the role of CASZ1 in neuroblastoma tumorigenesis and development.
- To correlate CASZ1 expression levels with clinical and pathological features of NB.
- To explore the functional impact of CASZ1 restoration in NB cells.
Main Methods:
- Quantitative real-time PCR to assess CASZ1 expression.
- Analysis of gene expression profiling data.
- Functional assays including cell differentiation, adhesion, migration, and tumorigenicity studies after CASZ1 restoration.
Main Results:
- Low CASZ1 expression significantly correlates with high-risk NB features (age, 1p LOH, MYCN amplification) and decreased survival.
- CASZ1 expression is higher in differentiated NB and can be induced by retinoids and epigenetic agents.
- Restoration of CASZ1 induces NB cell differentiation, enhances adhesion, inhibits migration, and suppresses tumorigenicity.
Conclusions:
- CASZ1 is a critical modulator of neural cell development and acts as a tumor suppressor in neuroblastoma.
- Disruption of CASZ1 expression contributes to the malignant phenotype of NB.
- CASZ1 represents a potential therapeutic target for neuroblastoma treatment.
Related Concept Videos
01:05Cancer-Critical Genes II: Tumor Suppressor Genes
When the function of certain critical genes, especially those involved in cell cycle regulation and cell growth signaling cascades, gets disrupted, it upsets the cell cycle progression. Such cells with unchecked cell cycles start proliferating uncontrollably and eventually develop into tumors.
Such genes that act...
01:05Cancer-Critical Genes II: Tumor Suppressor Genes
When the function of certain critical genes, especially those involved in cell cycle regulation and cell growth signaling cascades, gets disrupted, it upsets the cell cycle progression. Such cells with unchecked cell cycles start proliferating uncontrollably and eventually develop into tumors.
Such genes that act...
01:12Loss of Tumor Suppressor Gene Functions
When the tumor suppressor genes develop mutations or are lost, cells start growing out of control, leading to cancer. However, a single functional copy of the tumor suppressor gene is enough for the cells to maintain their normal functions and cell...
01:12Loss of Tumor Suppressor Gene Functions
When the tumor suppressor genes develop mutations or are lost, cells start growing out of control, leading to cancer. However, a single functional copy of the tumor suppressor gene is enough for the cells to maintain their normal functions and cell...
01:20The Retinoblastoma Gene
The first-ever tumor suppressor gene called Rb was identified in retinoblastoma - a rare eye tumor in children. In inherited forms of the disease, a child inherits one defective copy of the Rb gene, which predisposes them to retinoblastoma. However,...
01:20The Retinoblastoma Gene
The first-ever tumor suppressor gene called Rb was identified in retinoblastoma - a rare eye tumor in children. In inherited forms of the disease, a child inherits one defective copy of the Rb gene, which predisposes them to retinoblastoma. However,...