ZNF671 Antibody

What is ZNF671 and what is its role in cancer progression?

ZNF671 (zinc finger protein 671) is a member of the KRAB-ZF (KRAB-ZFP) family of mammalian transcriptional repressors that functions as a tumor suppressor in multiple cancer types. The protein contains zinc finger domains and an N-terminal KRAB domain, allowing it to regulate gene expression by binding to specific DNA sequences.

Multiple studies have demonstrated that ZNF671:

• Is frequently downregulated in various cancers through promoter hypermethylation

• Inhibits epithelial-mesenchymal transition (EMT), migration, and invasion in cancer cells

• Correlates with improved survival when expressed at higher levels

• Regulates several cancer-related pathways including Wnt/β-catenin signaling

In single-cell RNA sequencing analyses, ZNF671 expression is positively associated with DNA damage, apoptosis, and DNA repair processes while being negatively correlated with angiogenesis, differentiation, and proliferation in certain cancer subtypes .

What applications can ZNF671 antibody be used for and what is its reactivity profile?

Based on validated research applications, ZNF671 antibody (21329-1-AP) can be used for:

The antibody shows specific reactivity with human samples, with positive Western blot detection confirmed in multiple cell lines including A549, HepG2, HeLa, MCF-7, MDA-MB-231, SKOV-3, and U-251 cells. Positive IF/ICC detection has been specifically validated in U-251 cells .

What is the molecular weight of ZNF671 protein and how should it appear on Western blots?

ZNF671 protein has:

• Calculated molecular weight: 63 kDa (556 amino acids)

• Observed molecular weight range: 61-70 kDa

When performing Western blot analysis, researchers should expect to see a band within this range. The slight variation in observed weight can result from post-translational modifications or splice variants. For accurate identification, positive controls from cell lines with known ZNF671 expression (such as U-251 or HeLa) should be used alongside experimental samples .

How does ZNF671 expression correlate with patient survival in different cancer types?

Multiple studies have established a significant correlation between ZNF671 expression and patient outcomes:

Research has shown that ZNF671 is epigenetically silenced through DNA methylation in multiple tumor types, which serves as a mechanism for its downregulation. This epigenetic silencing pattern appears to be a common feature across various epithelial solid tumors and contributes to the poor prognosis associated with reduced ZNF671 expression .

What signaling pathways does ZNF671 regulate in cancer cells?

ZNF671 influences several key signaling pathways in cancer cells:

• Wnt/β-catenin Pathway: Gene set enrichment analysis (GSEA) has shown that ZNF671 expression is significantly correlated with Wnt/β-catenin signaling. Overexpression of ZNF671 inhibits cell cycle progression and metastasis by weakening this pathway, subsequently downregulating the expression of downstream target genes .

• MAPK Pathway: In laryngeal squamous cell carcinoma, ZNF671 has been shown to bind directly to the promoter region of MAPK6, inhibiting its expression. This was confirmed through chromatin immunoprecipitation and luciferase reporter experiments .

• EMT Regulation: Western blot analysis validated that ZNF671 overexpression increases expression of epithelial marker E-cadherin and decreases expression of mesenchymal marker Vimentin across multiple cancer cell lines including U87, U251, A375, MDA-MB-231, and BT-549 .

• Notch Signaling: Research has indicated that ZNF671 can have a cancer-inhibiting function in colorectal carcinoma via the deactivation of Notch signaling .

How can ZNF671 methylation be used as a biomarker for cancer detection?

ZNF671 methylation has shown significant promise as a biomarker in multiple cancer types:

• Cervical Cancer Screening: The ZNF671 methylation test (ZNF671m test) has demonstrated superior performance for CIN3+ (cervical intraepithelial neoplasia grade 3 or cervical cancer) detection. Studies found that the ZNF671m test achieved significantly higher sensitivity (relative sensitivity: 1.56, 95% CI: 1.29–1.89) with comparable specificity (relative specificity: 1.08, 95% CI: 0.96–1.22) compared to HPV16/18 genotyping .

• Head and Neck Cancer: ZNF671 promoter methylation levels are significantly increased in primary tumor DNA compared with matching non-tumor tissue. Three CpG loci within the ZNF671 promoter show consistent hypermethylation in tumor samples: cg08048222, cg19246110, and cg21305471 .

• Nasopharyngeal Carcinoma: A combination of RERG and ZNF671 methylation rates in circulating cell-free DNA has been identified as a novel biomarker for screening of nasopharyngeal carcinoma .

For clinical implementation, quantitative methylation-specific PCR (qMSP) can be used to measure ZNF671 methylation levels in tissue samples or liquid biopsies.

What are the optimal conditions for detecting ZNF671 using Western blot?

For optimal ZNF671 detection by Western blot, follow these methodological guidelines:

Protocol Overview:

• Protein isolation: Use RIPA lysis buffer to extract proteins from cells or tissues

• Sample preparation: Load 40-60μg of total protein per lane

• Gel electrophoresis: 10% SDS-PAGE gel is recommended

• Transfer: Use PVDF or nitrocellulose membrane

• Blocking: 5% skim milk or BSA for 1 hour at room temperature

• Primary antibody: Anti-ZNF671 (21329-1-AP) at 1:500-1:1000 dilution, incubated overnight at 4°C

• Secondary antibody: Anti-rabbit HRP at 1:5000 dilution, incubated for 1 hour at room temperature

• Detection: Use enhanced chemiluminescence (ECL) reagent

Critical Parameters:

• Use β-actin (1:1000-1:2000) as loading control

• Include positive control cell lysates (e.g., HeLa, U-251, or A549 cells)

• Expected molecular weight range is 61-70 kDa

This protocol has been validated in multiple studies investigating ZNF671's role in cancer .

What controls should I include when studying ZNF671 expression in cancer models?

To ensure experimental validity when studying ZNF671 expression, incorporate these essential controls:

For Western Blot/Protein Expression:

• Positive control: Cell lines with confirmed ZNF671 expression (U-251, HeLa, A549, HepG2)

• Loading control: β-actin or GAPDH (1:1000-1:2000)

• Negative control: Cell lines with ZNF671 knockdown or known low expression

For Functional Studies:

• Vector-only control: When overexpressing ZNF671, include empty vector transfection

• Scrambled siRNA: When performing siRNA knockdown of ZNF671

• Wild-type control: Unmanipulated cells for baseline comparison

For Methylation Studies:

• Normal adjacent tissue: When analyzing tumor samples

• Unmethylated DNA control: Commercially available or from normal tissue

• Fully methylated control: In vitro methylated DNA

These controls are critical for result interpretation and were consistently implemented across the published studies on ZNF671 .

How can I effectively overexpress or knockdown ZNF671 in cell culture models?

Based on successful methodology from published research:

For ZNF671 Overexpression:

• Use pEnter-ZNF671 plasmid (or equivalent expression vector containing full-length ZNF671)

• Transfect cells using Lipofectamine 3000 or equivalent reagent

• Maintain cells for 48-72 hours post-transfection before analysis

• Confirm overexpression by Western blot using anti-ZNF671 antibody (21329-1-AP at 1:500 dilution)

For ZNF671 Knockdown:

• Design siRNAs targeting ZNF671 (or use validated commercial options)

• Transfect cells using Lipofectamine RNAiMAX or equivalent

• Maintain cells for 48-72 hours post-transfection

• Confirm knockdown efficiency by qRT-PCR and Western blot

Cell Lines Successfully Used:

• NSCLC lines: A549

• CNS cancer lines: U87, U251

• Breast cancer lines: MDA-MB-231, BT-549, MCF-7

• Laryngeal cancer lines: AMC-HN-8, TU177

• Other: HeLa, HepG2, melanoma A375, SKOV-3

The functional effects of ZNF671 modulation can be assessed through:

• Proliferation assays (MTT, EdU incorporation)

• Migration/invasion assays (Transwell, wound healing)

• EMT marker analysis (E-cadherin, Vimentin by Western blot)

• In vivo tumor growth in mouse xenograft models

What are the key considerations when analyzing ZNF671 expression in tumor vs. normal tissues?

When analyzing ZNF671 expression in comparative tumor-normal studies, researchers should address these critical factors:

• Expression-methylation correlation:

  • ZNF671 gene expression is often inversely correlated with promoter methylation

  • Three key CpG loci should be analyzed: cg08048222, cg19246110, and cg21305471

  • Expression data should be interpreted alongside methylation status

• Cell type heterogeneity:

  • Single-cell RNA sequencing reveals ZNF671 plays different roles in cancer subpopulations

  • In glioblastoma, ZNF671 correlates positively with DNA repair, DNA damage, and apoptosis in some cell groups but shows different associations in others

  • Bulk tissue analysis may mask these heterogeneous effects

• Statistical approaches:

  • Use paired t-tests when comparing matched tumor-normal samples

  • Report methylation as M-values or β-values with appropriate statistical tests

  • For survival analysis, use Kaplan-Meier with log-rank tests and Cox proportional hazards models

• Technical validation:

  • Confirm RNA expression changes with protein levels (RT-PCR plus Western blot)

  • Use multiple technical and biological replicates

  • Include appropriate positive and negative controls

Studies have consistently shown that ZNF671 is downregulated in multiple cancer types compared to matched non-tumor tissues, with corresponding increases in promoter methylation .

How can I analyze ZNF671 methylation data in clinical samples?

For rigorous analysis of ZNF671 methylation in clinical contexts:

Methodological Approach:

• Sample preparation:

  • Extract DNA from fresh frozen or FFPE tissues, or liquid biopsies

  • Include matched normal tissue when possible

  • Process samples in batches with technical controls

• Methylation analysis techniques:

  • Methylation-specific PCR (MSP): Qualitative assessment

  • Quantitative MSP (qMSP): Quantitative measurement

  • Bisulfite sequencing: High-resolution CpG-level analysis

  • Methylation arrays: Genome-wide context (focus on cg08048222, cg19246110, cg21305471)

• Data normalization and analysis:

  • Express methylation as β-values (0-1 scale) or M-values (logit transformation)

  • Use appropriate housekeeping genes for normalization in qMSP

  • Apply batch correction methods for multi-batch studies

• Clinical correlation:

  • Correlate methylation levels with clinical parameters (stage, grade, survival)

  • Define appropriate cutoffs for dichotomization (ROC curve analysis)

  • Calculate sensitivity, specificity, and predictive values for diagnostic applications

In head and neck cancer, significantly increased DNA methylation (expressed as M-values) has been observed for all three CpG loci within the ZNF671 promoter: cg08048222 (-1.17 ± 2.43 in tumor versus -4.49 ± 0.66 in non-tumor, p < 0.001), cg19246110 (-0.80 ± 2.12 versus -3.65 ± 0.92, p < 0.001), and cg21305471 (-1.92 ± 2.27 versus -4.91 ± 0.55, p < 0.001) .

How can I distinguish between direct and indirect effects of ZNF671 on downstream targets?

To differentiate direct from indirect regulatory effects of ZNF671:

Methodological Approaches:

• Chromatin Immunoprecipitation (ChIP):

  • Use anti-ZNF671 antibody to immunoprecipitate ZNF671-bound DNA

  • Analyze by PCR (for candidate genes) or sequencing (ChIP-seq for genome-wide binding)

  • This approach successfully identified direct binding of ZNF671 to the MAPK6 promoter region

• Luciferase Reporter Assays:

  • Clone the promoter region of putative target genes into reporter plasmids

  • Co-transfect with ZNF671 expression or knockdown constructs

  • Measure luciferase activity to assess direct transcriptional effects

  • This approach was used to determine the specific binding site of ZNF671 on the MAPK6 promoter

• Time-course Experiments:

  • Monitor gene expression changes at multiple time points after ZNF671 modulation

  • Early changes (0-6h) often represent direct effects

  • Later changes (>12h) may indicate secondary responses

• Transcription Factor Binding Site Analysis:

  • Perform in silico analysis to identify potential ZNF671 binding motifs

  • Focus ChIP experiments on regions containing these motifs

  • Mutate predicted binding sites to confirm functionality

• Protein-protein Interaction Studies:

  • Use co-immunoprecipitation to identify proteins that interact with ZNF671

  • Mass spectrometry analysis can reveal components of ZNF671 transcriptional complexes

  • Identifies indirect effects mediated through protein interactions rather than direct DNA binding

These approaches have been successfully used to characterize ZNF671's direct regulatory role on genes involved in the MAPK pathway and Wnt/β-catenin signaling .

What are the emerging applications of ZNF671 as a biomarker or therapeutic target?

Based on current research findings, ZNF671 shows significant potential as both a biomarker and therapeutic target:

As a Diagnostic/Prognostic Biomarker:

• ZNF671 methylation testing demonstrates superior performance for cervical cancer (CIN3+) detection compared to conventional methods

• Low ZNF671 expression consistently correlates with poor survival across multiple cancer types

• Combined methylation biomarker panels incorporating ZNF671 show promise for early cancer detection in liquid biopsies

As a Therapeutic Target:

• Restoration of ZNF671 expression could potentially inhibit tumor growth and metastasis

• Epigenetic drugs (DNA methyltransferase inhibitors) might restore ZNF671 expression

• Targeting pathways regulated by ZNF671 (Wnt/β-catenin, MAPK) could provide alternative therapeutic approaches

Future research directions should focus on:

• Elucidating the complete spectrum of genes directly regulated by ZNF671

• Developing improved methods for analyzing ZNF671 methylation in clinical samples

• Exploring combination therapies targeting ZNF671-related pathways

• Investigating ZNF671's role in response to conventional cancer therapies

• Developing strategies to restore ZNF671 expression or function in tumors