219362

Cathepsin B, Human Liver

Cathepsin B, Human Liver, CAS 9047-22-7, is a purified native cathepsin B from human liver, purified by affinity chromatography. Upregulated in many types of tumors.

• Synonym(s): Cathepsin B, Human Liver, cat B, cysteine cathepsin
• CAS Number: 9047-22-7
• Enzyme Commission number: 3.4.22.1 (BRENDA, IUBMB)
• UNSPSC Code: 12352202
• NACRES: NA.77

Properties

• biological source: human liver
• Quality Level: 100
• Assay: ≥95% (SDS-PAGE)
• form: liquid
• specific activity: ≥10 units/mg protein
• purified by: affinity chromatography
• manufacturer/tradename: Calbiochem^®
• storage condition: OK to freeze; avoid repeated freeze/thaw cycles
• technique(s): activity assay: suitable
• suitability: suitable for molecular biology
• application(s): life science and biopharma
• shipped in: wet ice
• storage temp.: −70°C
• Gene Information: human ... CTSB(1508)

Description

General description

Research area: Cell Signaling

Native cathepsin B from human liver, purified by affinity chromatography and HPLC. The most investigated enzyme of all lysosomal cysteine proteases. Cathepsin B belongs to the papain-like family of cysteine proteases and is produced as a preproenzyme. It is a bilobal protein, and its catalytic site is situated at the interface between the two lobes.

Application

Cathepsin B, Human Liver, has been used in:

• Diagnostics: as a potent and independent prognostic marker for endometrial cancer, pancreatic adenocarcinoma, and inflammatory disease.
• Drug development: during the neovascularization process and as a potent therapeutic target for various pathologies, cancer progression, and osteoarthritis in humans.
• Pharmacology: for increasing the therapeutic index of doxorubicin by incorporating the cathepsin B cleavable spacer Phe-Lys-4-aminobenzyloxycarbonyl into an albumin-binding prodrug.
• Molecular biology: in cathepsin B activity assay.

Biochem/physiol Actions

Cathepsin B acts as both endo and exopeptidase. While as an endopeptidase it cleaves amino acids with a large hydrophobic side chain in the P2 site of the protein/peptide substrate, on the other hand as an exopeptidase it eliminates two amino acids (dipeptide) from the C terminus of a polypeptide substrate, thereby categorizing the enzyme as a peptidyl dipeptidase. It maintains homeostatic metabolic activity within cells through regular turnover of both intracellular and extracellular proteins. Additionally, it is involved in various cellular functions like regulation of pro-enzyme and pro-hormone activation, tissue remodeling, antigen processing, apoptosis, and inflammatory responses to antigens. The expression and activity of cathepsin B have been linked to several pathologies, including cardiovascular disease, cancer, Alzheimer’s, arthritis, and pancreatitis. Overexpression of cathepsin B has been observed in brain, breast, gastric, prostate, esophageal, skin, lung, ovarian, colon, and thyroid cancers and correlates positively with their invasive and metastatic capabilities. Cathepsin B is shown to facilitate tumor invasion by dissolving extracellular barriers.

Warning

Toxicity: Standard Handling (A)

Unit Definition

One unit is defined as the amount of enzyme that will hydrolyze 1.0 µmol Z-RR-β-naphthylamide per min at 40°C, using 100 mM Na⁺/K⁺ pH 6.0, with 1.33 mM EDTA and 2 mM DTT as the activation buffer.

Physical form

In 50 mM sodium acetate buffer, 1 mM EDTA, pH 5.0.

Preparation Note

Prepared from tissues of individuals that have been shown by certified tests to be negative for HBsAg and for antibodies to HIV and HCV.

Reconstitution

Following initial thaw, aliquot and freeze (-70°C).

Other Notes

Hirai, K., et al. 1999. Hum. Pathol.30, 680.
Kostoulas, G., et al. 1999. FEBS Lett.455, 286.
Strojnik, T., et al. 1999. Clin. Cancer Res.5, 559.
Maquire, T.M., et al. 1998. Int. J. Biol. Markers13, 139.
Berquim, I.M., and Sloane, B.F. 1996. Adv. Exp. Med. Biol.389, 281.

Legal Information

CALBIOCHEM is a registered trademark of Merck KGaA, Darmstadt, Germany

Safety Information

• Storage Class Code: 11 - Combustible Solids
• WGK: WGK 3
• Flash Point(F): Not applicable
• Flash Point(C): Not applicable