MP5 peptide

MP5 peptide

• Handling and Storage of Synthetic Peptides
• Material Safety Data Sheets (MSDS)

Batch to batch variation of the purity

H-STDSTSAPASNLQPASEYS-OH

H-Ser-Thr-Asp-Ser-Thr-Ser-Ala-Pro-Ala-Ser-Asn-Leu-Gln-Pro-Ala-Ser-Glu-Tyr-Ser-OH

19

95.85%

C₇₈H₁₂₁N₂₁O₃₅

1912.9

Synthetic

Powder

MP5 is a 19 - mer MAREMO peptide (STDSTSAPASNLQPASEYS) that has significant impacts on tumor growth and various cellular mechanisms.
Inhibition of Tumor Growth and Metastasis
In the autologous NT193 murine breast cancer model, peritumorally injected MP5 accumulated in tumors in nude mice. It significantly reduced tumor growth, with 30% of treated tumors completely regressing. It also showed potential in inhibiting tumor cell dissemination as indicated by gene expression analysis of lung tissue.
Effects on Cell Proliferation and Apoptosis
MP5 affected cell cycle checkpoint and G2/M checkpoint gene signatures, downregulated mammary stem cell genes, and reduced the number of Ki67 + cells, indicating an impact on tumor cell proliferation.
It increased staining for the apoptosis marker cleaved caspase 3, enhancing tumor cell apoptosis. In vitro, it inhibited NT193 cell viability in a dose - dependent manner and had different effects on cell viability depending on the cell's epithelial or mesenchymal phenotype.
Impact on EMT and TRAIL Cytotoxicity
MP5 treatment enhanced interferon - gamma (IFNγ) and interferon - alpha (IFNα) response genes, upregulated the expression of the IFNγ response gene Tnfsf10 (encoding TRAIL) and the IFNα response gene Tnfrsf10b (encoding DR5).
It induced a mesenchymal - to - epithelial - transition (MET) - like state, enforced an E phenotype in cultured NT193M cells, and sensitized these cells to TRAIL cytotoxicity in a TNC - dependent manner.
Effects on Fibroblasts and Matrix Organization
MP5 caused a profound downregulation of several ECM genes and fibroblast markers, indicating fibroblast depletion and a reduction in matrix organization.
It also downregulated the hallmark angiogenesis gene set, reduced tumor blood vessels, and improved vessel coverage and reduced leakage, suggesting it normalizes the tumor vasculature.
Activation of Immunity
MP5 treatment enriched the antigen processing and cross - presentation gene signature, upregulated MHC class I and II variants and immunoproteasome complex subunits, increased macrophage infiltration and dendritic cell abundance, and enhanced the activity of CD8 + cytotoxic T lymphocytes. It also reduced the expression of M2 - type macrophage marker Mrc1, promoting antitumorigenic macrophage functionality.

Normally, this peptide will be delivered in lyophilized form and should be stored in a freezer at or below -20 °C. For more details, please refer to the manual: Handling and Storage of Synthetic Peptides

• Li C, Kaur A, Pavlidaki A, Spenlé C, Rajnpreht I, Donnadieu E, Salomé N, Molitor A, Carapito R, Wack F, Erne W, Lefebvre O, Averous G, Mitrentsi I, Loustau T, Orend G. Targeting the MAtrix REgulating MOtif abolishes several hallmarks of cancer, triggering antitumor immunity. Proc Natl Acad Sci U S A. 2024 Oct 15;121(42):e2404485121. doi: 10.1073/pnas.2404485121. Epub 2024 Oct 9. PMID: 39382998.

Trifluoroacetic acid (TFA) has a significant impact on peptides due to its role in the peptide synthesis process.

TFA is essential for the protonation of peptides that lack basic amino acids such as Arginine (Arg), Histidine (His), and Lysine (Lys), or ones that have blocked N-termini. As a result, peptides often contain TFA salts in the final product.

TFA residues, when present in custom peptides, can cause unpredictable fluctuations in experimental data. At a nanomolar (nM) level, TFA can influence cell experiments, hindering cell growth at low concentrations (as low as 10 nM) and promoting it at higher doses (0.5–7.0 mM). It can also serve as an allosteric regulator on the GlyR of glycine receptors, thereby increasing receptor activity at lower glycine concentrations.

In an in vivo setting, TFA can trifluoroacetylate amino groups in proteins and phospholipids, inducing potentially unwanted antibody responses. Moreover, TFA can impact structure studies as it affects spectrum absorption.