Recombinant Human CST2 protein(Met1-Ala141), His-tagged

• Cat.No.: CST2-3214H
• Product Overview: Recombinant Human CST2 (NP_001313.1) (Met 1-Ala 141) was expressed in HEK293, fused with a polyhistidine tag at the C-terminus.

Specification

• Species: Human
• Source: HEK293
• Tag: His
• Protein Length: 1-141 a.a.
• Form: Lyophilized from sterile PBS, pH 7.4. Normally 5 % - 8 % trehalose, mannitol and 0.01% Tween80 are added as protectants before lyophilization.
• Molecular Mass: The secreted recombinant human CST2 consists of 132 amino acids and migrates as an approximately 16 kDa band in SDS-PAGE under reducing conditions as predicted.
• Endotoxin: < 1.0 EU per μg of the protein as determined by the LAL method
• Purity: > 98 % as determined by SDS-PAGE
• Storage: Samples are stable for up to twelve months from date of receipt at -20°C to -80°C. Store it under sterile conditions at -20°C to -80°C. It is recommended that the protein be aliquoted for optimal storage. Avoid repeated freeze-thaw cycles.
• Reconstitution: It is recommended that sterile water be added to the vial to prepare a stock solution of 0.2 ug/ul. Centrifuge the vial at 4°C before opening to recover the entire contents.

Gene Information

• Gene Name: CST2 cystatin SA [ Homo sapiens ]
• Official Symbol: CST2
• Synonyms: CST2; cystatin SA; cystatin-SA; cystatin 2; cystatin-2; cystatin S5; cystatin-S5; cysteine-proteinase inhibitor; salivary cysteine (thiol) protease inhibitor; MGC71924
• Gene ID: 1470
• mRNA Refseq: NM_001322
• Protein Refseq: NP_001313
• MIM: 123856
• UniProt ID: P09228

Case Study

Case 1: Lu Y, et al. J Cancer Res Clin Oncol. 2024

Cystatin SA (CST2) is part of a group that inhibits cysteine proteases and has a curious role in various cancers. In gastric cancer, its true impact hasn't been fully uncovered yet. The findings show that CST2 levels are lower in gastric cancer tissues and cells. Interestingly, when CST2 is increased, it seems to slow cancer growth, but only in the cancerous cells, leaving normal cells untouched. Moreover, CST2 helps these cancer cells respond better to the chemo drug Oxaliplatin by acting through the PI3K/AKT pathway, making it a potential ally in tackling gastric cancer.

Fig1. The overexpression and knockdown efficiency of CST2 were confirmed using Western blot analysis.

Fig2. The effects of CST2 on apoptosis of GC cells under oxaliplatin treatment were assessed by measuring the percentages of apoptotic cells in each group using flow cytometry.

Case 2: Eliyahu E, et al. J Biol Chem. 2011

When acid ceramidase (AC) activates, it exposes a cysteine, raising the possibility that it’s regulated by cystatin proteins. Co-expressing AC with cystatin SA (cysSA) lowered AC activity and boosted ceramide levels. Knocking down cysSA reversed these effects, but adding back cysSA could restore them. Experiments confirmed cysSA interacts directly with AC, inhibiting its activity in a non-competitive way. By identifying inhibitory regions in cysSA, small peptides were created that also inhibit AC, offering potential new strategies to control AC in cancer cells.

Fig1. The effects of cysSA expression on AC activity.

Fig2. Protein lysates were prepared from HEK 293T17 cells transiently transfected with the AC cDNA, alone (−), or in combination with cysSA (+).

Application

Recombinant CST2 protein is grabbing attention in the world of cancer research, especially because its levels often go haywire in some tumors. Researchers are keen to see if tweaking CST2 could pave the way for new cancer treatments, focusing on stopping cancer cells in their tracks. By using the recombinant form, they're hoping to learn more about how CST2 interacts with proteases and whether it can help halt cancer progression. But it's not just about cancer. Since CST2 inhibits proteases, it could also have uses in other medical areas where controlling protease activity is crucial to avoid tissue harm. The recombinant version is a practical way to test its impact and think about using it in diseases that proteases might worsen. Overall, recombinant CST2 might help protect tissues and reveal fresh therapeutic avenues.

Fig1. Noninvasive sampling methods for detecting the mRNA or protein level of cystatin SN and the clinical application. (Bing Yan, 2023)