MNX1 Antibody
Description
Introduction
MNX1 (Motor Neuron and Pancreas Homeobox 1) is a transcription factor critical for motor neuron development and pancreatic β-cell differentiation. MNX1 antibodies are essential tools for detecting and studying this protein in research contexts, including cancer biology, neurodevelopment, and diabetes. These antibodies enable visualization of MNX1 expression patterns, functional assays, and mechanistic studies across diverse biological systems.
MNX1 Antibody Overview
MNX1 antibodies are immunoreagents designed to bind specific epitopes of the MNX1 protein. They are widely used in techniques such as:
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Western blotting (WB)
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Immunohistochemistry (IHC)
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Immunofluorescence (IF)
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Flow cytometry (FACS)
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Chromatin immunoprecipitation (ChIP)
Key characteristics of MNX1 antibodies include:
Cancer Biology
MNX1 antibodies have been pivotal in uncovering MNX1’s oncogenic roles:
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Breast Cancer: MNX1 is upregulated in HER2-positive subtypes and correlates with tumor size, lymph node metastasis, and poor survival . Antibodies validated MNX1’s interaction with HER2-associated pathways and cell cycle regulators (e.g., p21) .
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Cervical Cancer: MNX1 promotes proliferation and invasion by suppressing p21 expression. Knockdown studies using siRNA and antibody-based validation showed reduced tumor growth in xenograft models .
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Colorectal Cancer (CRC): MNX1 overexpression enhances migration/invasion via an E2F4-mediated feedback loop. Antibodies confirmed MNX1-E2F4 interactions in ChIP assays .
Neurodevelopment
MNX1 antibodies identified its role in motor neuron (MN) specification:
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MNX1 represses pan-neuronal genes in developing MNs, maintaining their identity. ChIP-seq revealed MNX1 binding to enhancers of neuronal genes (e.g., CHX10) .
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In zebrafish and mouse models, MNX1 loss disrupts MN differentiation, validated via IHC .
Leukemia and Epigenetic Regulation
MNX1 overexpression alters histone methylation (H3K4me, H3K27me3) and induces DNA damage in hematopoietic stem cells, driving leukemia. Antibodies confirmed MNX1’s interaction with methionine cycle enzymes .
Key Research Insights from Antibody-Based Studies
Challenges and Limitations
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Specificity Issues: Some antibodies exhibit cross-reactivity with unrelated epitopes, necessitating peptide blocking controls .
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Species Reactivity: Limited cross-species utility (e.g., Xenopus-specific antibodies fail in mammalian systems) .
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Application Variability: Performance differs across techniques (e.g., ABN174 works in IHC but not IF) .
Product Specs
Constituents: 50% Glycerol, 0.01M PBS, pH 7.4
Target Background
- MNX1 may directly regulate TrkB expression, potentially increasing metastatic potential by suppressing anoikis and enhancing adhesion to the extracellular matrix. PMID: 30066929
- Pathogenic variants in MNX1 have been identified in 28% of all Currarino syndrome (CS) cases and 25% of sporadic cases. The clinical phenotype exhibited variability in patients with and without pathogenic variants; no significant genotype-phenotype correlation was observed. PMID: 29401559
- Research suggests that RGS12 acts as a potential tumor-suppressor gene in African-American prostate cancer, reducing AKT and MNX1 expression, thereby establishing a novel oncogenic axis in this specific disease context. PMID: 28611045
- MNX1 has emerged as a novel targetable oncogene with increased expression in African-American prostate cancer, which is associated with aggressive disease. PMID: 27578002
- Studies have demonstrated for the first time that the long non-coding RNA MNX1-AS1 functions as an oncogene in ovarian cancer. PMID: 28414551
- Research has shown that microRNAs miR-200a and miR-141 can inhibit the expression of Hlxb9 by binding to its mRNA 3'UTR. Moreover, the expression of miR-200a and miR-141 exhibits an almost reciprocal relationship with that of Hlxb9. Overexpression of miR-200a and miR-141 has been observed to downregulate the expression of pancreatic progenitor cell markers, including Hlxb9. PMID: 26801823
- The nuclear positioning of the HLXB9 gene has been monitored at different developmental stages. PMID: 25136833
- A study reports the results of MNX1 mutational screening in a series of 28 cases suspected of having Currarino Syndrome and the characterization of 10 novel mutations. PMID: 24095820
- NKX2-2 and MNX1 have been identified as etiological genes for neonatal diabetes. PMID: 24411943
- Both pHLXB9 and active GSK-3beta are elevated in beta cells with menin knockdown, as well as in MEN1-associated beta cell tumors (insulinomas). PMID: 24425879
- A study describes a Norwegian family with typical Currarino syndrome in which a heterozygous deletion removes the entire MNX1 gene, but no other known genes. The study also reports MNX1 mutations in three other Norwegian families and confirms that the GCC12 repeat (c.373_375[12]) is a normal allelic variant. PMID: 23370340
- HB9 binds to the prostaglandin E receptor 2 promoter and inhibits intracellular cAMP mobilization in leukemic cells. PMID: 23048027
- A new HLXB9 gene mutation has been identified in a Chinese family with members suffering from Currarino syndrome. PMID: 21960426
- Two novel mutations in the MNX1 gene have been identified in cases with Currarino syndrome. PMID: 22820079
- Two previously described mutations, a de novo nonsense mutation (p.Gln212X) and a maternally inherited frameshift mutation (p.Pro18ProfsX38) were found among 14 Currarino syndrome patients with presacral tumors. PMID: 21763840
- Hypermethylation of HLXB9 results in loss of expression and is associated with acute lymphoblastic leukemia. PMID: 21069786
- HLXB9 is overexpressed in patients with infantile acute myeloid leukemia. PMID: 19446746
- Incomplete Currarino syndrome with a more favorable prognosis has been associated with autosomal dominant pattern homeobox gene HLXBV9 mutation. PMID: 20146075
- A study reports on MNX1 mutations in a family segregating Currarino syndrome (CS) and 3 sporadic CS patients, as well as on the clinical characteristics of affected individuals. PMID: 19853743
- A mutation in the HLXB9 transcription factor has been implicated as a cause of an autosomal dominant form of sacral agenesis. PMID: 11940082
- Chromosomal rearrangements of the HLXB9 protein locus at 7q36 were not detected in Hodgkin lymphoma cells, unlike acute myeloid leukemia subsets expressing HLXB9. PMID: 15772702
- A high incidence of t(7;12)(q36;p13) in infant myeloid leukemia is associated with ectopic expression of HLXB9. PMID: 16646086
- This study confirms that familial Currarino syndrome (CS) patients in Korea share the same genetic background as other ethnicities and reaffirms the phenotypic variability among CS patients with the same mutation. PMID: 17612791
- A report describes 23 novel mutations in 26 patients among a series of 50 index cases with Currarino syndrome. PMID: 18449898
- The MNX1-ETV6 fusion gene has been identified in an acute megakaryoblastic leukemia. PMID: 18940475
- Ectopic expression of the HLXB9 gene is associated with an altered nuclear position in t(7;12) leukemias. PMID: 19212340
Q&A
What is MNX1 and why is it significant in research?
MNX1, also known as Hb9, Hlxb9, HOXHB9, or SCRA1, is a motor neuron and pancreas homeobox protein with a molecular weight of approximately 40.6 kilodaltons . This development-related gene has gained significant attention in cancer research due to its abnormal overexpression in several cancer types, including cervical cancer, breast cancer, prostate cancer, hepatocellular carcinoma, and acute myeloid leukemia .
What applications are most suitable for MNX1 antibody detection?
Based on current research practices, MNX1 antibodies have demonstrated efficacy in multiple experimental applications:
| Application | Suitability | Key Considerations |
|---|---|---|
| Western Blot (WB) | High | Effective for protein expression quantification |
| Immunohistochemistry (IHC) | High | Valuable for tissue localization studies |
| Immunocytochemistry (ICC) | Moderate to High | Useful for cellular localization |
| Immunofluorescence (IF) | Moderate to High | Enables co-localization studies |
| ELISA | Moderate | Appropriate for protein quantification |
| Flow Cytometry | Limited | Less commonly used for MNX1 detection |
The selection of appropriate application depends on your specific research question. For cancer tissue studies, IHC on tissue microarrays (TMAs) has proven particularly valuable for correlating MNX1 expression with clinical outcomes .
How should researchers validate MNX1 antibody specificity?
A methodological approach to MNX1 antibody validation should include:
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Positive and negative controls: Use tissues or cell lines with known MNX1 expression profiles. For instance, cervical cancer cell lines show high MNX1 expression and can serve as positive controls .
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Knockdown/overexpression validation: Compare antibody signals in MNX1-knockdown versus wild-type cells. This approach was successfully employed in studies examining MNX1's role in cervical cancer progression .
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Cross-reactivity assessment: Test the antibody against potential orthologous proteins, particularly when working with non-human samples, as MNX1 antibodies may react with human, mouse, rat, dog, and pig orthologous proteins .
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Molecular weight verification: Confirm that the detected band appears at the expected molecular weight of approximately 40.6 kDa .
What mechanisms underlie MNX1's role in cancer progression?
Recent research has elucidated several mechanisms through which MNX1 contributes to cancer progression:
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Cell cycle regulation: In cervical cancer, MNX1 promotes malignant progression by transcriptionally repressing p21^cip1^, a cyclin-dependent kinase inhibitor, thereby accelerating cell cycle transition particularly at the G2/M checkpoint .
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Proliferation enhancement: Knockdown of MNX1 inhibits cancer cell proliferation, as demonstrated through Real-Time Cellular Analysis (RTCA), colony formation assays, and EdU incorporation assays .
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Migration and invasion promotion: MNX1 enhances metastatic potential by increasing cancer cell migration and invasion capabilities, as shown in transwell and matrigel assays .
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Therapeutic sensitivity modulation: In HER2-positive breast cancer, MNX1 influences sensitivity to anti-HER2 therapies, with higher MNX1 expression correlating with better response to treatments like trastuzumab .
Understanding these mechanisms provides potential targets for therapeutic intervention and biomarker development.
How does MNX1 expression correlate with clinical outcomes across different cancer types?
MNX1 expression shows distinct prognostic implications depending on cancer type:
This paradoxical behavior of MNX1 across different cancer types underscores the importance of context-specific analysis when studying MNX1 as a biomarker.
What methodological approaches are optimal for quantifying MNX1 expression in clinical samples?
For robust MNX1 quantification in clinical samples, consider these methodological approaches:
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Immunohistochemistry scoring: Implement a standardized scoring system based on staining intensity and percentage of positive cells. Studies have successfully used this approach to categorize MNX1 expression as high or low in tissue microarrays .
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RNA-seq analysis: High-throughput RNA sequencing provides comprehensive gene expression data and has been used to identify MNX1 as differentially expressed between treatment-responsive and non-responsive patient groups .
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qRT-PCR validation: Quantitative real-time PCR offers a more accessible method to validate expression differences observed in RNA-seq and can be performed on smaller tissue samples .
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ROC curve analysis: To evaluate MNX1's potential as a diagnostic biomarker, ROC analysis can determine its predictive accuracy. In breast cancer studies, MNX1 demonstrated good predictive performance (AUC = 0.721, CI = 0.684–0.758) in distinguishing invasive ductal carcinoma from normal tissues .
How can researchers troubleshoot inconsistent MNX1 antibody staining?
When encountering inconsistent MNX1 antibody staining, consider these methodological solutions:
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Optimize antibody concentration: Titrate antibody concentrations to determine the optimal working dilution that maximizes specific signal while minimizing background.
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Evaluate fixation protocols: MNX1 detection may be sensitive to fixation conditions. Compare formalin-fixed paraffin-embedded (FFPE) versus frozen sections to determine optimal preservation of the epitope.
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Adjust antigen retrieval: Test different antigen retrieval methods (heat-induced versus enzymatic) and buffer compositions (citrate versus EDTA-based) to optimize epitope exposure.
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Consider blocking conditions: Non-specific binding can be reduced by optimizing blocking solutions (BSA, normal serum, or commercial blockers) and incubation times.
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Validate with alternative antibodies: If available, compare results using antibodies from different suppliers or those targeting different epitopes of MNX1 to confirm staining patterns .
What considerations are important for dual or multiple staining involving MNX1 antibodies?
For successful multiplexed staining involving MNX1:
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Antibody compatibility: Select primary antibodies raised in different host species to avoid cross-reactivity of secondary antibodies.
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Sequential versus simultaneous staining: Evaluate whether sequential or simultaneous incubation protocols yield better results for your specific antibody combinations.
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Signal separation: For fluorescent detection, ensure sufficient spectral separation between fluorophores to prevent bleed-through, particularly important when co-localizing MNX1 with subcellular markers.
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Chromogenic multiplexing: When using chromogenic detection, consider the order of antibody application and development to optimize visualization of each target.
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Controls for interaction studies: When examining MNX1's interaction with other proteins (such as p21^cip1^), include appropriate controls to validate co-localization or co-immunoprecipitation results .
How should researchers interpret contradictory findings about MNX1's role across different cancer types?
When faced with apparently contradictory findings regarding MNX1's role in different cancers:
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Consider tissue-specific context: MNX1 functions within distinct molecular networks in different tissues. In cervical cancer, MNX1 appears to promote malignancy through p21^cip1^ repression , while in HER2-positive breast cancer, it may enhance therapeutic sensitivity through different mechanisms .
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Evaluate methodological differences: Contradictions may arise from differences in detection methods, scoring systems, or statistical approaches. Standardizing these factors across studies can help reconcile disparate findings.
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Examine pathway interactions: MNX1 may interact with different signaling pathways depending on the cellular context. Perform pathway analysis to identify cancer-specific interacting partners.
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Consider genetic background: The impact of MNX1 expression may be modified by the presence of other genetic alterations specific to each cancer type.
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Temporal dynamics: MNX1's role may evolve during cancer progression, necessitating analysis at multiple disease stages to fully understand its function.
What are emerging research directions for MNX1 antibodies in precision medicine?
Future research directions for MNX1 antibodies in precision medicine include:
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Biomarker development: Further validate MNX1 as a predictive biomarker for treatment response, particularly in HER2-positive breast cancer where it shows promise in identifying patients likely to benefit from anti-HER2 therapies .
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Therapeutic targeting: Explore the potential of targeting MNX1 directly or its downstream effectors as a therapeutic strategy, especially in cancers where it promotes malignancy .
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Combination therapies: Investigate how MNX1 expression levels might inform optimal combination therapy selection by predicting synergistic or antagonistic interactions.
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Liquid biopsy applications: Develop methods to detect MNX1 in circulating tumor cells or cell-free DNA as a non-invasive approach to monitor disease progression and treatment response.
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Single-cell analysis: Apply single-cell techniques to understand heterogeneity in MNX1 expression within tumors and its implications for treatment resistance and tumor evolution.
