CYB561D2 Antibody

What is CYB561D2 and why is it significant in cancer research?

CYB561D2 (cytochrome b561 family member D2) is an antioxidant protein that catalyzes ascorbate-dependent trans-membrane ferric-chelate reduction and plays a crucial role in oxidation-reduction reactions . It has gained significant research interest due to its involvement in multiple cancer types, including gliomas, breast cancer, and prostate cancer. Studies have shown that CYB561D2 is upregulated in gliomas compared to normal tissue, and its expression correlates with high tumor grade and poor patient survival . In breast cancer, CYB561D2 is highly expressed, particularly in HER2-positive subtypes, and is associated with adverse outcomes . Understanding CYB561D2's role in cancer progression provides insights into novel therapeutic targets, particularly in pathways connecting reactive oxygen species (ROS) homeostasis and tumor immunity.

What are the common applications of CYB561D2 antibodies in research?

CYB561D2 antibodies are employed in multiple experimental approaches:

These applications have been instrumental in characterizing CYB561D2's expression patterns across different cancer types and its correlation with clinical outcomes .

What are the known aliases and molecular characteristics of CYB561D2?

CYB561D2 is also known by several aliases including 101F6, TSP10, and XXCOS-LUCA11.4 . It belongs to the Cytochrome b561 (CYB561) family and has a calculated molecular weight of approximately 24 kDa . The protein contains characteristic domains that facilitate its function in electron transfer and ascorbate regeneration. Understanding these molecular features is essential when selecting antibodies for specific epitopes and designing experimental controls.

How should CYB561D2 antibodies be validated for research applications?

A comprehensive validation strategy for CYB561D2 antibodies should include:

• Specificity testing: Verify antibody specificity using positive and negative controls. For CYB561D2, this could include CYB561D2-expressing cell lines (e.g., glioma cell lines U251, U87) versus knockout models or low-expressing normal tissues .

• Multiple technique validation: Confirm consistent results across different applications (WB, IHC, ELISA) as demonstrated in commercial antibody validations .

• Peptide blocking: Use antigenic peptides (such as VSNAYLYRKRIQP) to block CYB561D2 antibody binding and confirm specificity .

• Molecular weight verification: Confirm detection at the expected molecular weight (~24 kDa).

• Knockout/knockdown validation: Compare antibody signals in wild-type versus CYB561D2 knockout or knockdown samples using techniques like CRISPR/Cas9 or shRNA .

What experimental controls are essential when studying CYB561D2 expression in cancer tissues?

When studying CYB561D2 expression in cancer tissues, the following controls are crucial:

How can CYB561D2 knockdown/knockout models be efficiently generated for functional studies?

Effective generation of CYB561D2 knockdown/knockout models can be achieved through:

• shRNA approach: Short hairpin RNA constructs targeting human CYB561D2 mRNA sequences can be cloned into lentiviral vectors (e.g., pLentiLox3.7) for stable knockdown . Validation should include RT-qPCR to verify reduced expression.

• CRISPR/Cas9 system: All-in-One Lentivector sets containing sgRNAs targeting CYB561D2 exonic regions can generate frameshift mutations resulting in gene knockout . This system typically includes:

  • A set of three sgRNA targets designed to cleave exonic gDNA

  • Cas9 expression component

  • Selection marker (e.g., puromycin resistance)

• Validation methods:

  • Surveyor assay to detect genome modifications

  • Sanger sequencing to confirm frameshift mutations

  • Western blot to verify protein loss

  • Functional assays to confirm phenotypic changes

How does CYB561D2 regulate STAT3 signaling in cancer, and what are the implications for immunotherapy?

CYB561D2 has been shown to activate STAT3 signaling through several mechanisms:

• Direct activation: CYB561D2 and its functional product ascorbate activate STAT3 phosphorylation (p-STAT3 Tyr705) in a dose-dependent manner .

• ROS-mediated pathway: H₂O₂ treatment induces CYB561D2 expression, which subsequently activates STAT3 signaling, suggesting CYB561D2 mediates ROS-STAT3 crosstalk .

• Immunosuppressive gene regulation: CYB561D2 overexpression increases PD-L1, CCL2, and TDO2 expression through STAT3 activation, which can be blocked by STAT3 inhibitors like C188-9 .

The implications for immunotherapy are significant:

• CYB561D2-induced upregulation of PD-L1 may contribute to immune checkpoint inhibition

• The positive correlation between CYB561D2 and immunosuppressive molecules suggests targeting CYB561D2 could potentially enhance immunotherapy response

• Co-culture experiments show that CYB561D2 overexpression in glioma cells induces T cell apoptosis and inhibits IL-2 secretion in a STAT3-dependent manner, indicating direct immunosuppressive effects

What are the contradictions in the literature regarding CYB561D2's role across different cancer types?

Several notable contradictions exist in the literature:

These contradictions highlight the need for cancer type-specific investigations of CYB561D2 function and caution against generalizing findings across different tissues.

How can multi-omics approaches incorporate CYB561D2 antibody data to understand its role in redox regulation and cancer progression?

Integrating CYB561D2 antibody data with multi-omics approaches can provide comprehensive insights:

• Proteomics integration:

  • Combine CYB561D2 immunoprecipitation with mass spectrometry to identify interaction partners

  • Correlate CYB561D2 protein levels (antibody-based) with global proteome changes

  • Study post-translational modifications that may regulate CYB561D2 function

• Transcriptomics correlation:

  • Associate CYB561D2 protein expression with transcriptome profiles in datasets like TCGA

  • Identify gene modules co-expressed with CYB561D2 across cancer types

  • Validate expression correlations with immunosuppressive genes (PD-L1, CCL2, TDO2)

• Metabolomics connection:

  • Link CYB561D2 expression to ascorbate and iron metabolism markers

  • Study redox status markers in relation to CYB561D2 expression

  • Examine ROS-related metabolites in CYB561D2 high vs. low expressing tumors

• Clinical data integration:

  • Correlate CYB561D2 IHC scores with patient outcomes across multiple cohorts

  • Develop multi-factor prognostic models incorporating CYB561D2 expression

  • Study treatment response patterns based on CYB561D2 status

How can researchers address inconsistent CYB561D2 antibody staining patterns in tissue samples?

Inconsistent staining patterns can be addressed through:

• Optimization of antigen retrieval:

  • Test multiple retrieval methods (heat-induced vs. enzymatic)

  • Optimize pH conditions (citrate buffer pH 6.0 vs. EDTA buffer pH 9.0)

  • Adjust retrieval duration based on tissue type

• Antibody validation across tissue types:

  • Verify antibody performance in control tissues with known expression

  • Implement peptide blocking controls as demonstrated in glioma studies

  • Use multiple antibodies targeting different epitopes

• Tissue processing considerations:

  • Standardize fixation conditions (time, temperature, fixative)

  • Control section thickness (recommended 6 μm for CYB561D2 IHC)

  • Minimize ischemia time for fresh specimens

• Quantification approaches:

  • Implement standardized scoring methods (e.g., Quickscore method)

  • Use digital pathology analysis for objective quantification

  • Apply double-blind assessment by multiple observers

What strategies can improve detection sensitivity for low CYB561D2 expression in normal tissues?

To improve detection of low CYB561D2 expression:

• Signal amplification techniques:

  • Implement tyramide signal amplification (TSA)

  • Use polymer-based detection systems

  • Consider chromogenic vs. fluorescent detection based on expected expression levels

• Sample preparation optimization:

  • Minimize background through optimized blocking

  • Test fresh frozen vs. FFPE samples for sensitivity comparison

  • Consider mouse-on-mouse blocking for mouse tissues

• Antibody selection and concentration:

  • Compare different antibody clones for sensitivity in low-expressing tissues

  • Titrate antibody concentration specifically for normal tissues

  • Consider more sensitive detection formats (e.g., ELISA or enhanced chemiluminescence for WB)

• Complementary techniques:

  • Validate with RNA in situ hybridization

  • Use RT-qPCR for quantitative expression analysis

  • Implement laser capture microdissection to isolate specific cell populations

How can researchers address challenges in differentiating CYB561D2 from other CYB561 family members?

Distinguishing CYB561D2 from other family members requires:

• Epitope selection:

  • Choose antibodies targeting unique regions of CYB561D2 not conserved in other family members

  • Verify epitope specificity through sequence alignment analysis

  • Test for cross-reactivity with recombinant proteins of related family members

• Validation in knockout models:

  • Confirm antibody specificity in CYB561D2 knockout models

  • Test antibody reactivity in cells overexpressing specific CYB561 family members

  • Use siRNA to specifically knockdown CYB561D2 and verify antibody signal reduction

• Complementary approaches:

  • Implement PCR with primers specific to CYB561D2

  • Use unique peptide tags in expression constructs

  • Apply isoform-specific mass spectrometry approaches

• Expression pattern analysis:

  • Compare with known tissue distribution patterns of CYB561 family members

  • Analyze subcellular localization differences between family members

  • Implement co-staining with antibodies to related family members to assess overlap