Cathepsin B and cysteine proteinase inhibitors in bronchoalveolar lavage fluid of lung cancer patients.
The enzymatic activity and the concentration of cathepsin B (CB), determined by ELISA, and total inhibitory activity of cysteine proteinase inhibitors (CPIs) were measured in bronchoalveolar lavage fluid (BALF) of lung tumor patients (n = 49). Significantly higher CB activity and concentration was found in BALF from metastasis (n = 15), when compared to squamous cell carcinoma (SCC; n = 15) and small cell lung carcinoma (SCLC; n = 7). Patients with adenocarcinoma (n = 12) also secreted considerably more CB, about 14- and 3.3-fold, compared to SCC and SCLC patients, respectively. However, only tumor patients without inflammation were considered because the comparison of patients with lung tumors (n = 49) and with other non-neoplastic lung diseases (n = 18) showed no differences due to high CB in BALF of patients with inflammatory conditions, present in some patients from both groups. Immunolabeling of tumor BALF proteins revealed CB immunoreactivity at molecular sizes that corresponded to the size of its precursor and mature forms, as well as to complexes with kininogen(s) and low molecular weight CPIs. Stefins A and B, but not cystatins C and S appeared in the complexes with CB.
Lüthgens
K
K
Thoraxklinik Heidelberg-Rohrbach, Heidelberg, Germany.
Ebert
W
W
Trefz
G
G
Gabrijelcic
D
D
Turk
V
V
Lah
T
T
D000230:Adenocarcinoma / Q000737:chemistry / Q000201:enzymology*; D001992:Bronchoalveolar Lavage Fluid / Q000737:chemistry*; D018288:Carcinoma, Small Cell / Q000737:chemistry / Q000201:enzymology*; D002294:Carcinoma, Squamous Cell / Q000737:chemistry / Q000201:enzymology*; D002401:Cathepsin B / Q000032:analysis*; D015853:Cysteine Proteinase Inhibitors / Q000032:analysis*; D006801:Humans; D008175:Lung Neoplasms / Q000737:chemistry / Q000201:enzymology* / Q000556:secondary
D015853:Cysteine Proteinase Inhibitors; D002401:Cathepsin B