NDRG2 Human

What is the genomic structure and expression pattern of NDRG2 in humans?

NDRG2 is one member of the human NDRG gene family, encoding a protein highly homologous to Ndrg1 . The gene is expressed in multiple tissue types but shows particularly high expression in brain, heart, and skeletal muscle. In normal tissues, NDRG2 expression is typically higher than in corresponding tumor tissues, as demonstrated in colorectal cancer where the median immunohistochemistry (IHC) score of NDRG2 was significantly lower in tumor tissues [4.50 (range 0.00-12.00)] compared to adjacent normal tissues [10.00 (range 0.00-12.00)] .

Methodologically, researchers should employ quantitative PCR (qPCR) for mRNA assessment and immunohistochemistry or Western blotting for protein expression analysis. When designing primers for NDRG2, it's important to account for potential alternative splicing variants to ensure comprehensive detection.

How is NDRG2 regulated at the transcriptional level?

NDRG2 expression is down-regulated by Myc via transcriptional repression. Research has shown that high levels of NDRG2 are observed when Myc expression is reduced in differentiated cells, whereas low levels of NDRG2 are detected following increased Myc expression upon serum stimulation . Ectopic expression of c-Myc dramatically reduces cellular Ndrg2 protein and mRNA levels .

The c-Myc-mediated repression of NDRG2 requires association with Miz-1 and possibly the recruitment of epigenetic factors such as histone deacetylases to the promoter region . Researchers investigating this interaction should employ chromatin immunoprecipitation (ChIP) assays to confirm binding of transcription factors to the NDRG2 promoter, and luciferase reporter assays to quantify transcriptional activity under different conditions.

What is the structural characterization of the NDRG2 protein?

For researchers interested in NDRG2 structure-function relationships, techniques such as X-ray crystallography, cryo-electron microscopy, or nuclear magnetic resonance spectroscopy would be appropriate. Mutagenesis studies should focus on conserved structural features that suggest involvement in molecular interactions, particularly helix α6 which plays a crucial role in the suppression of TCF/β-catenin signaling in colorectal cancer tumorigenesis .

How does NDRG2 function as a tumor suppressor in different cancer types?

The tumor-suppressive mechanisms of NDRG2 appear to involve inhibition of tumor growth, migration, proliferation, adhesion, and invasion . In colorectal cancer specifically, NDRG2 has been shown to suppress TCF/β-catenin signaling through molecular interactions involving helix α6 .

Researchers investigating NDRG2's tumor suppressor functions should employ multiple methodological approaches:

• Gene knockout/knockdown studies using CRISPR-Cas9 or shRNA

• Overexpression models using stable transfection or inducible systems

• Pathway analysis to identify downstream effectors

• In vivo xenograft models to confirm in vitro findings

• Correlation analysis between NDRG2 expression and clinical parameters in patient samples

What clinicopathological features correlate with NDRG2 expression in human cancers?

Meta-analysis data shows that low NDRG2 expression is related to multiple phenotypes of tumor aggressiveness, including:

• Advanced clinical stage (OR = 3.21, 95% CI: 1.96–5.26, P < .001)

• Lymph node metastasis (OR = 2.14, 95% CI: 1.49–3.07, P < .001)

• Poor differentiation (OR = 0.60, 95% CI: 0.45–0.81, P = .001)

These correlations have been observed across various solid tumors, suggesting NDRG2 may be a meaningful biomarker of poor prognosis and a potential therapeutic target .

For researchers investigating NDRG2 as a prognostic biomarker, tissue microarray analysis with large patient cohorts is recommended. Methodology should include multivariate analysis adjusting for known prognostic factors to determine NDRG2's independent prognostic value, and Kaplan-Meier survival analysis to visualize the impact of NDRG2 expression on patient outcomes.

How can we target NDRG2 or its regulatory pathways for cancer therapy?

Given NDRG2's tumor suppressor functions, therapeutic strategies could focus on:

• Upregulating NDRG2 expression through epigenetic modifiers that may counter Myc-mediated repression

• Inhibiting the Myc-Miz-1 interaction that represses NDRG2 transcription

• Developing peptide mimetics based on critical NDRG2 interaction domains, particularly helix α6

• Designing small molecules that might restore NDRG2 function in tumor cells

Methodologically, researchers should:

• Perform high-throughput drug screening to identify compounds that upregulate NDRG2

• Use reporter assays to monitor NDRG2 promoter activity in response to potential therapeutic agents

• Conduct structure-based drug design targeting the Myc-Miz-1 interaction

• Validate therapeutic approaches in patient-derived xenograft models

What role does NDRG2 play in neuronal cell death and neurodegenerative diseases?

NDRG2 has been implicated in neuronal cell death regulation and neurodegenerative diseases, particularly Alzheimer's disease (AD). Several lines of evidence support this role:

• NDRG2 is phosphorylated by Death-associated protein kinase 1 (DAPK1) on Ser350, which activates NDRG2 function in neuronal cell death regulation

• NDRG2 overexpression has been shown to increase apoptosis

• NDRG2 expression is increased after focal cerebral ischemia

• NDRG2 expression levels are upregulated in human AD patient brains

• NDRG2 phosphorylation is increased in neurodegenerative diseases

• NDRG2 single-nucleotide polymorphisms occur in late-onset AD patients

Importantly, levels of phosphorylated NDRG2 Ser350 and DAPK1 were significantly increased in human AD brain samples, suggesting this pathway may be involved in AD pathogenesis .

Researchers studying NDRG2 in neurodegeneration should:

• Utilize immunohistochemistry and Western blotting with phospho-specific antibodies to detect activated NDRG2

• Employ in vitro neuronal models to study the effects of NDRG2 modulation on cell survival

• Investigate NDRG2 knockout or knock-in animal models to assess cognitive and pathological outcomes

• Explore the interaction between NDRG2 and other AD-related pathways such as tau phosphorylation or amyloid processing

How does NDRG2 phosphorylation regulate its function in neural tissues?

NDRG2 phosphorylation appears to be a critical regulatory mechanism for its function. Death-associated protein kinase 1 (DAPK1) has been identified as a kinase that binds to and phosphorylates NDRG2 on Ser350 . This phosphorylation appears to activate NDRG2 function in neuronal cell death regulation.

For researchers investigating NDRG2 phosphorylation:

• Employ mass spectrometry to identify all phosphorylation sites on NDRG2

• Use phosphomimetic (S→D/E) and phospho-null (S→A) mutants to study the functional consequences of specific phosphorylation events

• Develop and utilize phospho-specific antibodies for detecting activated NDRG2 in tissue samples

• Investigate the kinase-substrate interaction using co-immunoprecipitation and kinase assays

• Examine the effects of kinase inhibitors on NDRG2 phosphorylation and function

What are the optimal methods for detecting and quantifying NDRG2 expression in human tissues?

Researchers have several options for detecting and quantifying NDRG2:

• mRNA detection:

  • RT-qPCR with primers specific to NDRG2

  • RNA-seq for genome-wide expression analysis

  • In situ hybridization for spatial localization

• Protein detection:

  • Western blotting using validated antibodies

  • Immunohistochemistry (IHC) for tissue localization

  • Enzyme-linked immunosorbent assay (ELISA) for quantification

  • Mass spectrometry for detection of post-translational modifications

For IHC scoring of NDRG2 in tumor tissues, researchers have used systems ranging from 0-12 based on staining intensity and percentage of positive cells . When reporting NDRG2 expression, it's important to clearly define the scoring system and include both tumor and matched normal tissues as controls.

What animal models are available for studying NDRG2 function in vivo?

Several animal models are available for NDRG2 research:

• Knockout models: NDRG2 knockout mice have been generated and can be used to study the physiological and pathological roles of NDRG2 in vivo .

• Conditional knockout models: Tissue-specific deletion of NDRG2 using Cre-loxP systems allows for examination of tissue-specific functions.

• Transgenic overexpression models: Models overexpressing wild-type or mutant NDRG2 can help understand gain-of-function effects.

• Xenograft models: Human cancer cells with modified NDRG2 expression can be implanted into immunodeficient mice to study tumor growth and metastasis.

When using these models, researchers should consider:

• Complete phenotypic characterization including histopathological analysis

• Age-dependent effects, as NDRG2 functions may vary during development and aging

• Environmental stressors that might reveal phenotypes not apparent under standard conditions

• The potential for compensatory mechanisms from other NDRG family members

How can single-cell analysis technologies advance our understanding of NDRG2 function?

Single-cell technologies offer new opportunities for NDRG2 research:

• Single-cell RNA sequencing (scRNA-seq) can reveal cell type-specific expression patterns of NDRG2 and identify rare cell populations with unique NDRG2 expression profiles.

• Single-cell proteomics can detect NDRG2 protein levels and modifications at the individual cell level.

• Spatial transcriptomics combines single-cell resolution with spatial information, allowing researchers to map NDRG2 expression within the tissue microenvironment.

• CyTOF (mass cytometry) enables simultaneous detection of NDRG2 along with multiple other proteins in single cells.

These approaches can help address questions such as:

• How does NDRG2 expression vary among different cell types within tumors or brain tissue?

• Is NDRG2 expression heterogeneous within apparently homogeneous cell populations?

• How does the spatial distribution of NDRG2-expressing cells relate to pathological features?

• What are the cell type-specific interaction partners of NDRG2?

How might NDRG2 serve as a biomarker for cancer prognosis and treatment response?

For clinical implementation, researchers should:

• Establish standardized assays for NDRG2 detection in clinical samples

• Conduct large-scale validation studies in diverse patient cohorts

• Determine optimal cutoff values for "low" versus "high" NDRG2 expression

• Investigate NDRG2 as a companion diagnostic for specific therapies

• Explore liquid biopsy approaches (circulating tumor DNA, exosomes) for non-invasive NDRG2 assessment

Additionally, researchers should investigate whether NDRG2 expression predicts response to specific treatments, particularly those targeting pathways related to NDRG2 function or regulation.

What are the emerging connections between NDRG2 and metabolism in cancer and neurodegeneration?

NDRG2 is reportedly involved in cellular metabolism processes, including hormone, ionic, and liquid metabolism, as well as stress responses such as responses to hypoxia and lipotoxicity . These connections may be particularly relevant for both cancer and neurodegeneration.

Research methodologies to explore these connections should include:

• Metabolomic analysis of cells/tissues with altered NDRG2 expression

• Isotope tracing to track specific metabolic pathways affected by NDRG2

• Investigation of NDRG2 interactions with key metabolic enzymes or regulators

• Assessment of NDRG2's impact on mitochondrial function and energy production

• Examination of NDRG2's role in cellular response to metabolic stress

This research direction may reveal novel therapeutic opportunities targeting metabolic vulnerabilities in NDRG2-deficient tumors or NDRG2-overexpressing neurodegenerative conditions.

How do the different NDRG family members interact or compensate for each other?

While this FAQ focuses on NDRG2, it's important to consider its relationship with other NDRG family members (NDRG1, NDRG3, and NDRG4). Currently, there's limited information on how these family members might interact or compensate for each other's functions.

Research approaches to address this question include:

• Simultaneous profiling of all NDRG family members in normal and diseased tissues

• Generation of combinatorial knockout models (e.g., NDRG1/NDRG2 double knockout)

• Investigation of shared binding partners and signaling pathways

• Comparative structural analysis to identify conserved functional domains

• Evolutionary analysis to understand the diversification of NDRG family functions

Understanding these relationships may explain why NDRG2 knockout does not always produce expected phenotypes and could reveal synergistic therapeutic opportunities targeting multiple NDRG family members.