A multi‐functional peptide molecule was rational designed to use as gelator, dyes separation agent and metal ions adsorbent. The peptide molecule consists of phenylalanine‐phenylalanine‐alanine‐cysteine‐aspartic acid with a protective group of acetyl, simplified as Ac‐FFACD‐OH. FF is the critical composition of gelator and contributes to the formation of gels in a range of pH values from 1.0 to 6.0. The application as drug delivery system (DDS) of gels was tested by encapsulating DOX without destroying the gel structure. The in vitro release behaviors were investigated at different pH, showing a rapid release at pH 5.5 while a slow release at pH 7.4. Among all the amino acids, D is one of the only two acidic amino acids, which can bring acidity and electronegativity to peptide molecules. The electrostatic attraction makes the peptide to be a good adsorption agent for cationic dyes and repulsive towards anionic dyes. Adsorption experiments show that the adsorption efficiency is higher than 90% for cationic dyes and lower than 25% for anionic dyes. In a separation experiment, about 60% of the anionic dyes can be separated from the mixed dyes. Metal ions are also adsorbed with high adsorption efficiency of > 99% for Fe3+ and > 95% for Cu2+. The multi‐functions of the peptide molecule will provide theoretical basis and practical application for the goal‐directed design of peptide molecule structures.
Objective: To study the effect of peroxiredoxin 1 (PRDX1) on esophageal squamous carcinoma cells and determine whether it plays a role in regulating the PI3K/AKT signaling pathway. Methods: Three esophageal squamous cell carcinoma cell lines (Eca-109, EC9706, and KYSE150) and one normal cell line (human esophageal epithelial cells) were selected. The protein expression of peroxiredoxin 1 (PRDX1) and the activity of the PI3K/AKT pathway were detected via Western blotting. The proliferation ability of cells was detected through the MTT assay and cell clone formation. Apoptosis was detected using flow cytometry. Subsequently, cells were treated with a PI3K/AKT pathway inhibitor and activator, alone or in combination with silencing of PRDX1, and the above indicators were re-tested. Results: The expression of PRDX1 and activity of PI3K/AKT pathway-associated proteins were higher in esophageal cancer cells than in normal esophageal epithelial cells. Compared with normal human esophageal epithelial cells, the proliferation of the three types of esophageal cancer cells was increased, whereas their level of apoptosis was decreased (p<0.05). In Eca-109 cells (cell line with silenced expression of PRDX1), the expression of PRDX1 was significantly decreased. In contrast to the control group, the proliferation and clonality of cells in the silencing PRDX1 group was decreased, the proportion of apoptotic cells was increased, and the phosphorylation levels of PI3K and AKT were decreased (p<0.05). Compared with the control group, treatment with the inhibitor LY294002 alone significantly inhibited cell proliferation and promoted apoptosis (p<0.05); this effect was similar to that observed in the silencing PRDX1 group. Conclusion: PRDX1 was highly expressed in esophageal cancer cells. Silencing of PRDX1 can inhibit the proliferation of esophageal cancer cells and promote apoptosis. The mechanism involved in this process may be related to the inhibition of the PI3K/AKT signaling pathway.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.