Recombinant Human Coiled-coil domain-containing protein 167 (CCDC167)

What is the molecular structure and cellular localization of CCDC167?

CCDC167 belongs to the coiled-coil domain-containing protein family, characterized by alpha-helical structures that form coiled-coil motifs. These structures typically mediate protein-protein interactions and can form both homo- and heteromeric complexes. Research indicates that CCDC167 is expressed in various cell types, with particularly notable expression in breast cancer cell lines like MCF-7 .

The protein contains distinctive coiled-coil domains that facilitate its functional interactions with other cellular proteins. While detailed structural studies are still emerging, the presence of these coiled-coil domains suggests its involvement in protein complexes that regulate cellular processes including proliferation and potential inflammatory responses.

What are the expression patterns of CCDC167 in normal and pathological tissues?

CCDC167 demonstrates variable expression across tissues, with significant upregulation noted in multiple pathological states compared to normal tissue counterparts. Transcriptional expression analysis through platforms such as Oncomine reveals CCDC167 upregulation in breast cancer compared to normal tissues across 12 different studies . Additional data from GEPIA database comparing CCDC167 gene expression in normal and cancerous tissues from 33 TCGA RNA-Seq datasets found upregulation in 18 datasets, including invasive breast carcinoma .

In breast cancer specifically, CCDC167 expression correlates with histological differentiation, with increasing expression levels observed as tumors progress from nuclear grade I to III . Beyond cancer, CCDC167 also shows significant upregulation in asthma patients compared to healthy controls .

Expression patterns in different breast cancer cell lines revealed highest expression in MCF-7 cells (ER+ subtype) compared to other breast cancer cell lines including MDA-MB-231 (triple-negative subtype) and MDA-MB-468 (highly invasive) .

How can researchers effectively detect and measure CCDC167 expression?

Multiple methodological approaches have proven effective for detecting and measuring CCDC167 expression:

• Quantitative PCR (qPCR): This technique allows precise quantification of CCDC167 mRNA levels. In published studies, qPCR has been successfully used to detect differential expression across cell lines and to validate knockdown efficiency following shRNA transfection .

• RNA-Sequencing: High-throughput RNA-Seq has been employed to identify CCDC167 expression patterns across different tissues and pathological conditions. Databases such as TCGA and METABRIC provide valuable repositories of RNA-Seq data that include CCDC167 expression information .

• Bioinformatic Analysis: Tools like Oncomine, GEPIA, and Kaplan-Meier Plotter databases can be used to analyze CCDC167 expression across different cancer types and correlate expression with patient outcomes .

For optimal results, researchers should consider using multiple complementary techniques to validate expression findings, particularly when investigating novel tissue types or conditions where CCDC167 expression has not been previously characterized.

What are the key molecular pathways and gene networks associated with CCDC167?

CCDC167 functions within complex molecular networks, with co-expression analyses revealing significant pathway associations:

Cell Cycle Regulation: Co-expression analyses from both METABRIC and TCGA databases indicate that CCDC167-co-expressed genes are predominantly involved in cell cycle-related molecular processes . Pathway maps analysis through MetaCore demonstrates that genes co-expressed with CCDC167 participate in cell division progression, mitosis initiation, spindle assembly, and chromosome separation .

Immune Response Pathways: CCDC167 co-expressed genes affect immune response pathways including "immune response antigen presentation by MHC class I" and "immune response interferon (IFN)-alpha/beta signaling via phosphatidylinositol 3-kinase (PI3K) and nuclear factor (NF)-κB pathways" .

Metabolic Pathways: In asthma patients with high CCDC167 expression, GSEA analysis revealed upregulation of pathways including amino sugar and nucleotide sugar metabolism, biosynthesis of nucleotide sugars, glycosphingolipid biosynthesis, mucin-type O-glycan biosynthesis, and terpenoid backbone biosynthesis .

Ubiquitination-Related Pathways: CCDC167 co-expressed genes are involved in ubiquitination and ubiquinone metabolism pathways, suggesting potential roles in protein degradation and cellular respiration .

What experimental approaches are most effective for studying CCDC167 function?

Based on published research methodologies, several experimental approaches have proven effective for investigating CCDC167 function:

Gene Silencing via RNA Interference:

• shRNA-mediated knockdown of CCDC167 has successfully demonstrated its role in cellular proliferation. Plasmids containing CCDC167-shRNA can be transfected into relevant cell lines (e.g., MCF-7 for breast cancer studies) with knockdown efficiency validated by qPCR .

• In vivo, shCCDC167 has been used to downregulate CCDC167 expression in mouse models of asthma, confirming functional effects on inflammation and lung pathology .

Proliferation Assays:

• Short-term effects on cell proliferation can be measured using MTT assays, which have successfully detected differences between CCDC167-knockdown and control cells .

• Long-term proliferation effects are effectively assessed using colony-formation assays, which demonstrated suppressed growth in CCDC167-shRNA cells compared to controls .

Apoptosis Analysis:

• Flow cytometry with appropriate staining (e.g., Annexin V) has successfully quantified changes in early and late apoptosis following CCDC167 knockdown .

In Vivo Validation:

• For asthma research, ovalbumin (OVA)-induced asthmatic mice models with CCDC167 silencing have effectively demonstrated changes in inflammatory markers and lung injury .

• Analyses of bronchoalveolar lavage fluid (BALF) for inflammatory cells and cytokines provide quantitative measures of CCDC167's impact on inflammation .

Histological Assessment:

• Techniques including H&E staining, PAS staining, and Masson's trichrome staining have been used to evaluate tissue changes following CCDC167 manipulation in animal models .

How does CCDC167 contribute to breast cancer progression and what is its potential as a therapeutic target?

CCDC167 appears to play a significant role in breast cancer progression through multiple mechanisms:

Proliferation Enhancement: Knockdown of CCDC167 in MCF-7 breast cancer cells attenuates both short-term and long-term cell proliferation, while overexpression promotes cell proliferation . This suggests CCDC167 directly influences cancer cell growth capabilities.

Cell Cycle and Apoptosis Regulation: CCDC167 knockdown significantly alters expression of cell cycle-related and apoptosis-related genes, with increased percentages of both early and late apoptosis observed after CCDC167 knockdown .

Response to Chemotherapeutic Agents: Treatment with standard breast cancer chemotherapeutic agents (fluorouracil, carboplatin, paclitaxel, and doxorubicin) results in decreased expression of CCDC167 alongside suppressed growth of MCF-7 cells . This suggests CCDC167 downregulation may be a mechanism through which these drugs exert their anti-cancer effects.

The therapeutic potential of CCDC167 targeting is supported by evidence that:

• Established chemotherapeutic agents already indirectly target CCDC167 signaling

• Direct knockdown experiments demonstrate anti-cancer effects

• High expression correlates with poor prognosis, suggesting clinical relevance

Researchers developing therapeutic approaches targeting CCDC167 should consider both direct inhibition strategies and combination approaches with established chemotherapeutic agents that already influence CCDC167 expression.

What is the role of CCDC167 in asthma pathophysiology and how might it be leveraged as a biomarker?

Recent research has uncovered significant roles for CCDC167 in asthma:

Differential Expression in Asthma: CCDC167 expression is significantly elevated in asthma patients compared to healthy controls, as confirmed through analysis of the GSE67472 dataset .

Diagnostic Potential: Receiver Operating Characteristic (ROC) curve analysis demonstrates CCDC167 has an area under the curve of approximately 0.79, supporting its potential sensitivity and specificity as a diagnostic biomarker for asthma .

Functional Impact on Inflammation: In vivo studies using shCCDC167 to downregulate CCDC167 in asthmatic mice resulted in decreased levels of:

• Total inflammatory cell counts in bronchoalveolar lavage fluid (BALF)

• Specific inflammatory cell populations including eosinophils, macrophages, and lymphocytes

• Inflammatory cytokines including IgE, IL-4, IL-5, and IL-13

Effect on Lung Pathology: Histological examination revealed that CCDC167 silencing mitigated several pathological features of asthma in mouse models:

• Reduced cellular infiltration and alveolar structure damage (observed via H&E staining)

• Decreased goblet cell hyperplasia and airway mucus production (observed via PAS staining)

• Reduced smooth muscle hyperplasia and fibrosis in small airway tissues

Quantitative Improvements: Treatment with shCCDC167 reversed harmful changes in airway wall parameters including WAi/WAm levels (reduced in asthma) and N/Pi, WAi/Pi, and WAm/Pi levels (elevated in asthma) .

These findings collectively support CCDC167 as both a potential biomarker for asthma diagnosis and a therapeutic target. Its role in inflammatory pathways appears particularly significant in the asthmatic context, and silencing CCDC167 demonstrates measurable improvements in multiple aspects of asthma pathophysiology.

What are the challenges and considerations in developing experimental models to study CCDC167?

Researchers investigating CCDC167 face several methodological challenges:

Selection of Appropriate Cell Models:

• Different cell lines show variable endogenous expression of CCDC167. For breast cancer research, MCF-7 cells demonstrate highest expression compared to other breast cancer cell lines .

• Researchers must carefully select models that represent relevant CCDC167 expression patterns for their disease of interest.

In Vivo Model Development:

• For asthma studies, ovalbumin (OVA)-induced asthmatic mice have proven effective .

• For cancer studies, appropriate xenograft models reflecting CCDC167 expression patterns found in human tumors would be needed.

• Considerations for tissue-specific expression and regulation are essential for model validity.

Knockdown Efficiency and Specificity:

• Achieving consistent and significant knockdown is critical for reliable results. In published studies, knockdown efficiency has been validated through qPCR .

• Off-target effects must be controlled for, particularly when studying a protein involved in multiple pathways.

Pathway Complexity:

• CCDC167 functions within complex networks involving cell cycle regulation, immune response, and metabolism .

• Experimental designs must account for this complexity and include appropriate pathway analyses.

Translational Considerations:

• Bridging findings from in vitro and animal models to human disease requires careful validation.

• Clinical correlation studies, such as those examining CCDC167 expression in patient samples and correlating with outcomes, provide crucial translational context .

How might CCDC167 expression analysis be incorporated into clinical diagnostic workflows?

The potential of CCDC167 as a biomarker in both cancer and respiratory conditions suggests several approaches for clinical integration:

Diagnostic Applications:

• For asthma, ROC curve analysis demonstrates CCDC167 has approximately 0.79 area under curve, supporting potential utility in distinguishing asthma patients from healthy individuals .

• For breast cancer, elevated CCDC167 expression correlates with tumor progression from nuclear grade I to III, suggesting potential utility in tumor classification and grading .

Methodological Considerations for Clinical Implementation:

• Standardized Testing Protocols: Development of validated qPCR or immunohistochemistry protocols specifically for CCDC167 detection in clinical samples.

• Reference Ranges: Establishment of normal and pathological reference ranges across different tissue types and disease states.

• Integration with Other Biomarkers: Analysis of CCDC167 alongside established biomarkers to determine complementary or superior predictive value.

• Sample Collection and Processing: Standardization of sample handling to ensure reliable CCDC167 detection.

What research approaches can help resolve contradictions in CCDC167 functional data?

When investigating seemingly contradictory findings regarding CCDC167 function, researchers should consider:

Context-Dependent Effects:

• CCDC167 functions within different pathway networks in different tissues (e.g., cell cycle in breast cancer vs. inflammatory pathways in asthma) .

• Systematic cross-tissue comparisons of CCDC167 effects can help resolve apparent contradictions.

Methodological Harmonization:

• Standardized protocols for CCDC167 detection, knockdown, and functional assessment.

• Meta-analysis approaches combining data from multiple studies with consideration of methodological differences.

Comprehensive Pathway Analysis:

• Integration of multiple 'omics techniques (transcriptomics, proteomics, metabolomics) to capture the full spectrum of CCDC167's effects.

• Network analysis to identify context-specific interaction partners that might explain differential effects.

Temporal Considerations:

• Time-course experiments to distinguish between immediate and delayed effects of CCDC167 modulation.

• Analysis of CCDC167's role at different disease stages (e.g., initiation vs. progression).

What are the most promising unexplored aspects of CCDC167 biology?

Several areas of CCDC167 biology remain relatively unexplored and present significant research opportunities:

Structural Biology:

• Detailed characterization of CCDC167 protein structure, particularly its coiled-coil domains and their specific interaction partners.

• Structure-function relationships that might inform targeted therapeutic development.

Regulatory Mechanisms:

• Transcriptional and post-transcriptional regulation of CCDC167 expression under normal and pathological conditions.

• Potential epigenetic mechanisms controlling CCDC167 expression in different tissues.

Additional Disease Associations:

• Given its roles in both cancer and asthma, investigation of CCDC167 in other inflammatory disorders and malignancies.

• Potential shared mechanisms across seemingly distinct pathologies.

Interaction with Immune System:

• Detailed characterization of how CCDC167 influences immune cell function and inflammatory responses.

• Potential immunotherapeutic approaches targeting CCDC167-mediated immune dysregulation.

Therapeutic Development:

• Small molecule inhibitors specifically targeting CCDC167 or its critical interaction partners.

• RNA-based therapeutics for tissue-specific CCDC167 silencing.

How can multi-omics approaches enhance our understanding of CCDC167 function?

Multi-omics strategies offer powerful frameworks for comprehensive CCDC167 characterization:

Integrative Genomics:

• Correlation of CCDC167 genetic variants with expression levels and disease associations.

• Identification of regulatory elements controlling CCDC167 expression through integration of genomic and transcriptomic data.

Proteomics for Interaction Mapping:

• Immunoprecipitation coupled with mass spectrometry to identify CCDC167 binding partners.

• Quantitative proteomics before and after CCDC167 modulation to capture pathway effects.

Spatial Transcriptomics and Proteomics:

• Tissue-level resolution of CCDC167 expression patterns in complex tissues.

• Correlation with histopathological features and microenvironmental factors.

Metabolomics:

• Identification of metabolic pathways altered by CCDC167 expression changes.

• Potential biomarkers that reflect CCDC167 activity in biological fluids.

Single-Cell Analysis:

• Cell-type specific expression patterns of CCDC167 in heterogeneous tissues.

• Identification of particularly sensitive or resistant cell populations.