Description

Nori Porcine S100A4 ELISA Kit Summary

Alternative names for S100A4: S100 calcium-binding protein A4, S100-A4

Alternative name for porcine: Pig

Standard Curve

Kit Components
1. Pre-coated 96-well Microplate
2. Biotinylated Detection Antibody
3. Streptavidin-HRP Conjugate
4. Lyophilized Standards
5. TMB One-Step Substrate
6. Stop Solution
7. 20 x PBS
8. Assay Buffer

Other Materials Required but not Provided:
1. Microplate Reader capable of measuring absorption at 450 nm
2. Log-log graph paper or computer and software for ELISA data analysis
3. Precision pipettes (1-1000 µl)
4. Multi-channel pipettes (300 µl)
5. Distilled or deionized water

Protocol Outline
1. Prepare all reagents, samples and standards as instructed in the datasheet.
2. Add 100 µl of Standard or samples to each well and incubate 1 h at RT.
3. Add 100 µl of Working Detection Antibody to each well and incubate 1 h at RT.
4. Add 100 µl of Working Streptavidin-HRP to each well and incubate 20 min at RT.
5. Add 100 µl of Substrate to each well and incubate 5-30 min at RT.
6. Add 50 µl of Stop Solution to each well and read at 450 nm immediately.

Background: 

S100 calcium-binding protein A4 (S100A4) is a protein that is encoded by the S100A4 gene.^[1] S100A4 is a member of the S100 family of proteins containing 2 EF-hand calcium-binding motifs. S100 proteins are localized in the cytoplasm and/or nucleus of a wide range of cells, and involved in the regulation of a number of cellular processes such as cell cycle progression and differentiation. S100A4 may function in motility, invasion, and tubulin polymerization. Altered expression of S100A4 have been implicated in tumor metastasis. S100A4 is secreted by tumor and stromal cells, supports tumorigenesis by stimulating angiogenesis. Research demonstrated that S100A4 synergizes with VEGF via the RAGE receptor, in promoting endothelial cell migration by increasing KDR expression and MMP-9 activity. In vivo overexpression of S100A4 led to a significant increase in tumor growth and vascularization in a Porcine melanoma xenograft M21 model. Conversely, when silencing S100A4 by shRNA technology, a dramatic decrease in tumor development of the pancreatic MIA PaCa-2 cell line was observed. S100A4 is highly associated with components of the cytoskeleton and when this gene is upregulated, it changes the cell’s morphology, making it more susceptible to invasion from proteins, such as cathepsin B and cyclin B1, that contribute to metastasis.^[2] Together, these factors form polyploid giant cancer cells (PGCCs), which are highly proliferative and invasive. Experimental knockout therapy data have suggested that S100A4 exhibits a form of control over cathepsin B and cyclin B1, and that suppressing it can reduce the invasive capabilities of PGCCs and their daughter cells. Studies on invasive breast cancer have found that S100A4 plays a major role in high-density collagen deposition, which is one of the clinical symptoms of tumor metastasis. Significantly higher levels of S100A4 were found in samples that exhibited lymph node metastasis than in those that didn’t, indicating that abnormal collagen deposition could be contributed by S100A4.^[3] Not only does overexpression of S100A4 contribute to the formation of various cancers, but it also contributes to pathological factors associated with cancer and its progression.

References

1. Stoler A, Bouck N (1985). Proc. Natl. Acad. Sci. U.S.A. 82 (2): 570–4.
2. Fei F, Liu K, Li C, et al. (2020) Front Oncol. 10:182.
3. Wen X, Yu X, Tian Y, et al. (2020) Quant Imaging Med Surg. 10(3):624-633.

Product Citations