SHFM1 Antibody

What is SHFM1 and why is it significant in oncology research?

SHFM1 (Split hand and foot malformation 1) is a protein that has been identified as significantly upregulated in various cancers, particularly esophageal squamous cell carcinoma (ESCC). SHFM1 is considered an oncogenic protein that promotes tumor progression through multiple mechanisms. Research has demonstrated that SHFM1 is profoundly upregulated in ESCC tissues compared to normal tissues, with its expression positively associated with poor prognosis . The significance of SHFM1 in cancer research stems from its multifaceted roles in promoting malignant behaviors, including excessive proliferation, enhanced metastatic potential, and immune evasion capabilities. As a research target, SHFM1's involvement in activating critical oncogenic pathways such as NF-κB signaling makes it valuable for understanding cancer progression mechanisms and developing potential therapeutic interventions.

What are the standard experimental applications for SHFM1 antibodies?

SHFM1 antibodies are utilized across multiple experimental techniques in cancer research. The primary applications include:

• Western blotting: Typically employed at 1:500 dilution (as used with catalog number 10592-1-AP from Wuhan Sanying Biotechnology) for protein expression quantification .

• Immunohistochemistry (IHC): Used for analyzing SHFM1 expression patterns in both clinical specimens and xenograft tumor sections, providing spatial information about protein localization and expression levels within tissue contexts .

• Immunofluorescence assays: While not directly used for SHFM1 detection in the referenced study, this technique can be adapted using similar principles as those applied to P65 detection to investigate SHFM1 subcellular localization .

• Co-immunoprecipitation: Used for investigating protein-protein interactions involving SHFM1, particularly its interaction with signaling pathway components.

• Flow cytometry: Can be employed to detect SHFM1 expression at the cellular level when studying mechanisms related to immune response modulation.

How should researchers optimize western blotting protocols for SHFM1 detection?

For optimal western blot detection of SHFM1, researchers should follow these methodological recommendations:

• Protein extraction: Utilize RIPA buffer supplemented with protease inhibitors (e.g., phenylmethylsulfonyl fluoride) to effectively lyse ESCC tissues and cells while preserving protein integrity .

• Protein quantification: Employ BCA protein assay kits for accurate concentration determination before gel loading .

• Gel electrophoresis parameters: Load 15-30 μg of protein on 10% SDS-PAGE gels for optimal separation .

• Membrane transfer: Use polyvinylidene fluoride (PVDF) membranes for protein transfer, ensuring complete transfer of proteins in the relevant molecular weight range .

• Blocking conditions: Block membranes with 5% bovine albumin (BSA) for 1 hour at room temperature to minimize background signal .

• Antibody dilution: For SHFM1 primary antibody (such as cat. no. 10592-1-AP from Wuhan Sanying Biotechnology), a dilution of 1:500 has proven effective .

• Incubation conditions: Incubate with primary antibody overnight at 4°C followed by appropriate secondary antibody incubation according to standard protocols.

• Detection method: Use enhanced chemiluminescence systems compatible with your specific antibody for optimal signal detection.

It is crucial to include appropriate loading controls and validate antibody specificity through positive and negative controls.

What controls should be included when validating SHFM1 antibody specificity?

Validating SHFM1 antibody specificity requires implementation of multiple control strategies:

• Positive controls: Include cell lines or tissues known to express high levels of SHFM1, such as ESCC cell lines (TE-1 and KYSE-410) .

• Negative controls: Utilize tissues or cells with minimal SHFM1 expression or those where SHFM1 has been successfully knocked down using siRNA approaches. Two siRNA sequences proven effective for SHFM1 knockdown are:

  • siSHFM1-1: 5'-GAUCAAGAAGAUCAUGAAATT-3'

  • siSHFM1-2: 5'-AGAUCAAGAAGAUCAUGAATT-3'

• Peptide competition assay: Pre-incubate the antibody with purified SHFM1 peptide before application to verify that the observed signal is specifically blocked.

• Multiple antibody validation: When possible, confirm results using antibodies from different suppliers or those targeting different epitopes of SHFM1.

• Molecular weight verification: Ensure the detected band appears at the expected molecular weight for SHFM1.

• Recombinant expression: Compare signals between native samples and those overexpressing SHFM1 using expression vectors (such as pcDNA3.1) .

How can SHFM1 antibodies be employed to investigate NF-κB signaling in cancer?

SHFM1 antibodies are valuable tools for investigating the SHFM1-mediated activation of NF-κB signaling in cancer through several methodological approaches:

• Co-immunoprecipitation studies: Use SHFM1 antibodies to pull down protein complexes and analyze NF-κB pathway components (particularly P65) that interact with SHFM1 in cancer cells.

• Immunoblotting for pathway components: After SHFM1 manipulation (overexpression or knockdown), use antibodies against key NF-κB pathway components, particularly phosphorylated P65, to assess pathway activation status .

• Nuclear translocation assays: Complement SHFM1 studies with immunofluorescence assays using P65 antibodies (1:200 dilution) to visualize nuclear translocation of P65 as a direct indicator of NF-κB pathway activation following SHFM1 manipulation .

• Luciferase reporter assays: Utilize NF-κB response element-driven luciferase reporters to quantitatively measure NF-κB transcriptional activity in cells with modified SHFM1 expression.

• ChIP assays: Implement chromatin immunoprecipitation to determine if SHFM1 is directly involved in transcriptional complexes at NF-κB target gene promoters.

This multi-method approach allows researchers to establish both correlation and causation between SHFM1 expression and NF-κB pathway activation in cancer contexts.

What methodological approaches are effective for studying SHFM1's role in immune evasion?

To investigate SHFM1's role in immune evasion mechanisms, particularly its effect on NK cell cytotoxicity, researchers can implement the following methodological approaches:

• CFSE/PI flow cytometry assay: Co-culture NK-92 cells (effector cells) with SHFM1-manipulated cancer cells (target cells) labeled with CFSE, followed by PI staining to quantify dead target cells. This approach has successfully demonstrated that SHFM1 silencing increases target cell death while SHFM1 overexpression decreases NK-mediated killing .

• NK cell-mediated specific lysis assay: Calculate percent specific lysis to precisely quantify the impact of SHFM1 expression on cancer cell susceptibility to NK cell cytotoxicity .

• Cytolytic mediator quantification: Use ELISA to measure levels of granzyme B and perforin in culture supernatants from NK cells co-cultured with SHFM1-manipulated cancer cells. Research has shown that SHFM1 knockdown significantly increases these cytolytic agents while SHFM1 overexpression decreases their levels .

• Immunoblotting for immune checkpoint molecules: Assess expression levels of immune modulators, particularly PD-L1 and c-Myc, following SHFM1 manipulation. Data indicates that SHFM1 downregulation significantly reduces these immune checkpoint molecules .

• HLA class-I expression analysis: Monitor changes in HLA class-I expression on cancer cell surfaces following SHFM1 manipulation, as research has demonstrated upregulation of HLA class-I after SHFM1 knockdown .

What are common challenges with SHFM1 antibodies in immunohistochemistry and how can they be addressed?

Researchers frequently encounter several challenges when using SHFM1 antibodies for immunohistochemistry. Here are methodological solutions for each issue:

• Inconsistent staining intensity:

  • Standardize fixation protocols (4% paraformaldehyde fixation for 15 minutes at 37°C has proven effective)

  • Optimize antigen retrieval methods (citrate buffer pH 6.0 or EDTA buffer pH 9.0)

  • Titrate antibody concentration to determine optimal dilution for your tissue type

  • Ensure consistent incubation times and temperatures

• High background signal:

  • Increase blocking duration (1% BSA for at least 15 minutes at 37°C)

  • Include additional blocking steps with normal serum

  • Optimize washing steps between antibody applications

  • Consider using alternative detection systems if DAB-based methods show high background

• Weak or absent signal:

  • Test multiple antigen retrieval methods

  • Increase antibody concentration or incubation time

  • Use signal amplification systems like tyramide signal amplification

  • Confirm SHFM1 expression in your sample type through other methods (e.g., western blotting)

• Non-specific binding:

  • Validate antibody specificity using SHFM1-depleted controls (siRNA knockdown)

  • Include isotype controls

  • Pre-absorb antibody with recombinant SHFM1 protein to confirm specificity

How can researchers effectively use SHFM1 antibodies in multiplex immunofluorescence studies?

For effective multiplex immunofluorescence using SHFM1 antibodies alongside other markers, consider these methodological recommendations:

• Antibody panel design:

  • Select antibodies raised in different host species to avoid cross-reactivity

  • When studying NF-κB pathway, combine SHFM1 (rabbit) with P65 (mouse) antibodies

  • For immune response studies, include antibodies against c-Myc, PD-L1, and HLA class-I molecules

• Sequential staining protocol:

  • Begin with the lowest abundance target (typically SHFM1)

  • Apply tyramide signal amplification for weaker signals

  • Include stripping steps between antibody applications if using antibodies from the same species

  • Validate that each stripping step doesn't affect previously detected signals

• Spectral considerations:

  • Select fluorophores with minimal spectral overlap

  • Include proper single-stain controls for spectral unmixing

  • For SHFM1 detection, Cy3-labeled secondary antibodies (1:200 dilution) have proven effective

• Image acquisition and analysis:

  • Capture single channel images sequentially to minimize bleedthrough

  • Include unstained and single-stained controls for accurate compensation

  • Employ automated image analysis tools for quantitative assessment of co-localization

• Validation approaches:

  • Confirm staining patterns with individual antibodies before multiplexing

  • Include both positive and negative biological controls in each experiment

How does SHFM1 expression correlate with clinicopathological features in cancer?

SHFM1 expression demonstrates significant correlations with several clinicopathological features in cancer, particularly in ESCC. The following table summarizes these correlations based on clinical research data:

This data reveals that SHFM1 expression is significantly correlated with advanced TNM stage and positive lymph node metastasis (p<0.05), suggesting its potential value as a prognostic biomarker . Researchers investigating SHFM1 should consider these correlations when designing studies and interpreting results, particularly when evaluating SHFM1 as a potential therapeutic target.

What methodological approaches are recommended for analyzing SHFM1 expression in patient samples?

For comprehensive analysis of SHFM1 expression in patient samples, researchers should implement a multi-modal approach:

• Tissue processing and storage:

  • Flash-freeze surgical specimens immediately in liquid nitrogen for protein and RNA extraction

  • Fix paired samples in formalin and embed in paraffin for immunohistochemistry

  • Establish clear inclusion criteria for sample selection based on clinical parameters

• Immunohistochemical analysis:

  • Use validated SHFM1 antibodies at optimized dilutions

  • Score SHFM1 expression systematically (e.g., percentage of positive cells × staining intensity)

  • Include both tumor and adjacent normal tissue for comparative analysis

  • Employ double-blind scoring by multiple pathologists to minimize bias

• Western blot quantification:

  • Extract proteins using RIPA buffer with protease inhibitors

  • Quantify using BCA protein assay kits

  • Load equal amounts (15-30 μg) of protein for comparison

  • Include multiple housekeeping controls appropriate for cancer tissue

• Correlation with clinical data:

  • Develop comprehensive databases linking SHFM1 expression with:

    • TNM staging

    • Lymph node metastasis status

    • Histological grade

    • Patient survival data

  • Apply appropriate statistical methods to identify significant correlations

• Follow-up analysis:

  • Consider longitudinal sampling when possible to track changes in SHFM1 expression during disease progression

  • Correlate SHFM1 expression with treatment response data

What are the optimal methods for manipulating SHFM1 expression in experimental systems?

For effective manipulation of SHFM1 expression in experimental systems, researchers should consider these validated methodological approaches:

• siRNA-mediated knockdown:

  • Validated siRNA sequences:

    • siSHFM1-1: 5'-GAUCAAGAAGAUCAUGAAATT-3'

    • siSHFM1-2: 5'-AGAUCAAGAAGAUCAUGAATT-3'

  • Transfection protocol:

    • Combine 3.75 μl of 20 μM siRNA with 7.5 μl Lipofectamine® 3000 in 125 μl Opti-MEM

    • Incubate for 15 minutes at room temperature before adding to cells

  • Validation timeline: Confirm knockdown efficiency via western blot 48 hours post-transfection

• Plasmid-based overexpression:

  • Vector system: pcDNA3.1 vector carrying the SHFM1 coding sequence

  • Transfection protocol:

    • Complex 4 μg of expression plasmid with 7.5 μl Lipofectamine® 3000

    • Incubate for 15 minutes at room temperature before transfection

  • Control conditions: Include empty pcDNA3.1 vector as a negative control

• Stable cell line development:

  • Lentiviral transduction for long-term studies

  • Selection criteria: Determine appropriate antibiotic concentration through kill curve analysis

  • Clone selection: Isolate and validate individual clones for consistent SHFM1 expression levels

• CRISPR/Cas9 gene editing:

  • Design guide RNAs targeting early exons of SHFM1

  • Screen editing efficiency using T7 endonuclease assay

  • Confirm complete knockout through western blotting and sequencing

Each approach has specific applications depending on experimental goals, with transient methods appropriate for short-term studies and stable modifications necessary for in vivo and long-term investigations.

How can researchers effectively assess SHFM1's impact on cellular migration and invasion?

To comprehensively evaluate SHFM1's impact on cellular migration and invasion, researchers should implement these methodological approaches:

• Transwell migration assay:

  • Cell preparation: Suspend transfected cells (6×10³) in 200 μl serum-free medium

  • Chemoattractant: Add 800 μl medium containing 10% FBS to bottom chambers

  • Incubation parameters: Culture at 37°C with 5% CO₂ for 24 hours

  • Fixation and visualization: Fix with 4% paraformaldehyde for 15 minutes at 37°C, then stain with 0.4% crystal violet for 5 minutes

  • Quantification: Count migrated cells from five random fields under an inverted light microscope

• Matrigel invasion assay:

  • Chamber preparation: Pre-coat Transwell chambers with 40 μl of diluted (1:3) Matrigel and incubate at 37°C for 2 hours

  • Follow the same protocol as the migration assay for cell seeding, incubation, and quantification

• Wound healing assay:

  • Create a standardized scratch in confluent monolayers of SHFM1-manipulated cells

  • Monitor wound closure using time-lapse microscopy

  • Quantify healing rate through image analysis software

• 3D spheroid invasion assay:

  • Generate spheroids from SHFM1-manipulated cells using hanging drop or low-attachment plates

  • Embed spheroids in Matrigel or collagen matrices

  • Monitor and quantify invasive outgrowth over time

• Matrix metalloproteinase (MMP) activity assessment:

  • Evaluate MMP2 and MMP9 expression in SHFM1-manipulated cells through western blotting or qPCR

  • Consider zymography to assess functional MMP activity

  • Research has confirmed that SHFM1 manipulation affects MMP9 and MMP2 expression in ESCC tissues

These complementary approaches provide both qualitative and quantitative data on how SHFM1 modulates cancer cell migration and invasion capabilities.

How can researchers investigate SHFM1's role in modulating the tumor immune microenvironment?

To comprehensively investigate SHFM1's role in modulating the tumor immune microenvironment, researchers should implement these methodological approaches:

• NK cell cytotoxicity assays:

  • Co-culture system: Use ESCC cells as target cells and NK-92 cells as effector cells

  • Detection method: Implement CFSE/PI flow cytometry assay to quantify dead target cells

  • Analysis approach: Calculate the percentage of dead target cells and specific cell lysis

  • Expected outcomes: SHFM1 silencing significantly increases dead target cells, while overexpression decreases cytotoxicity

• Cytolytic mediator quantification:

  • Collect culture supernatants from NK cells co-cultured with SHFM1-manipulated cancer cells

  • Use ELISA to measure granzyme B and perforin levels

  • Research has shown that SHFM1 knockdown significantly increases these cytolytic agents

• Immune checkpoint molecule analysis:

  • Assess expression of immune modulatory proteins, particularly:

    • PD-L1: Significantly affected by SHFM1 expression levels

    • c-Myc: Downregulated following SHFM1 knockdown

    • HLA class-I molecules: Upregulated after SHFM1 knockdown

• Immune cell infiltration studies:

  • In xenograft models, analyze tumor-infiltrating lymphocytes using immunohistochemistry or flow cytometry

  • Compare immune infiltration patterns between SHFM1-high and SHFM1-low tumors

• Cytokine profiling:

  • Use multiplex assays to measure pro-inflammatory and immunosuppressive cytokines in:

    • Culture supernatants from SHFM1-manipulated cells

    • Tumor tissue extracts from xenograft models with varying SHFM1 expression

These approaches provide a comprehensive assessment of how SHFM1 influences cancer cell interactions with immune components, particularly focusing on mechanisms of immune evasion.

What are the best approaches for studying SHFM1's effects on NF-κB signaling in cancer progression?

To comprehensively analyze SHFM1's effects on NF-κB signaling in cancer progression, researchers should implement these methodological approaches:

• Phosphorylation status analysis:

  • Assess P65 phosphorylation levels through western blotting following SHFM1 manipulation

  • Use phospho-specific antibodies targeting key NF-κB pathway components

  • Research has demonstrated that SHFM1 manipulation affects P65 phosphorylation

• Nuclear translocation assessment:

  • Implement immunofluorescence assays using P65 antibodies (1:200 dilution)

  • Counterstain with DAPI to visualize nuclei

  • Quantify nuclear/cytoplasmic P65 ratios using image analysis software

  • Research confirms SHFM1 affects P65 nuclear translocation

• Transcriptional activity measurement:

  • Utilize NF-κB-responsive luciferase reporter assays

  • Measure activity in SHFM1-manipulated versus control cells

  • Include positive controls (TNF-α treatment) and negative controls (NF-κB inhibitors)

• Target gene expression analysis:

  • Quantify NF-κB target genes in SHFM1-manipulated cells through qPCR arrays

  • Confirm protein-level changes through western blotting

  • Focus particularly on genes involved in:

    • Cell proliferation (e.g., cyclin D1)

    • Metastasis (e.g., MMPs)

    • Immune modulation (e.g., PD-L1)

• Pathway intervention studies:

  • Use NF-κB pathway inhibitors in combination with SHFM1 manipulation

  • Assess whether NF-κB inhibition can rescue phenotypic effects of SHFM1 overexpression

  • Evaluate potential synergistic effects in therapeutic contexts

By integrating these approaches, researchers can establish both correlation and causation between SHFM1 expression, NF-κB pathway activation, and resulting cancer phenotypes.