Role of urinary cathepsin B and L in the detection of bladder urothelial cell carcinoma.

PURPOSE: We tested the hypothesis that urinary cathepsin B and L are associated with bladder cancer recurrence and invasiveness in patients with a history of nonmuscle invasive urothelial carcinoma of the bladder. MATERIALS AND METHODS: Cathepsin B and L, and NMP22 were determined in the urine specimens of 188 consecutive subjects with a history of treated urothelial carcinoma of the bladder, 31 with noncancerous urological conditions and 10 healthy subjects. Cathepsin B and L were analyzed as continuous and categorical variables based on their quartile distribution. RESULTS: Urinary cathepsin L was higher in the 122 patients with cystoscopic evidence of bladder tumor compared with levels in 107 with normal cystoscopy (median 5.9, IQR 4.4 vs 3.0, IQR 3.2, p <0.001). Higher levels of cathepsin L were associated with positive cytology assay results, higher NMP22 and T1 or greater pathological stage (each p <0.001). Area under the ROC curves of NMP22 and cathepsin L for bladder cancer detection were 0.704 (95% CI 0.637-0.772) and 0.793 (95% CI 0.736-0.850), respectively. On multivariate analysis cathepsin L, NMP22 and cytology were associated with invasive pathological stage (OR 1.29, 2.42 and 2.76, respectively, p

Cathepsins B, H, and L activities in urine of patients with transitional cell carcinoma of the bladder.

OBJECTIVES: Cathepsin B, H, and L (CB, CH, CL) are lysosomal proteolytic enzymes that belong to the group of cysteine proteinases. The imbalance between proteinases and their inhibitors is believed to correlate with tumor progression and shortened patient survival. In transitional cell carcinoma (TCC) only limited data have been published. METHODS: Using spectrofluorometric assays, catalytic activities of CB, CH, and CL in urine were measured to evaluate the potential diagnostic and prognostic value for patients with TCC of the bladder. Second morning urine was collected and used for measurements. CB, CH, and CL activities were determined for groups of patients with superficial disease (Ta-1, n = 43) and muscle-invasive tumors (T2, n = 18; or greater than T2, n = 9), as well as for different tumor grades (G1, n = 12; G2, n = 26; and G3, n = 31). For comparison, 14 urine samples from patients with bladder inflammation and 43 samples from a control group were also included. RESULTS: Compared with the control group, patients with superficial Stage Ta-T1 disease and muscle-invasive Stage T2 or greater disease, as well as patients with G3 tumors, revealed significantly higher urinary CL activity. CB and CH did not show any tumor-related activity increase. CB was significantly lower in patients with nonrecurrent tumors. CONCLUSIONS: These results suggest that elevated levels of CL in urine might be indicative of a cellular proteolytic imbalance in TCC of the bladder and may have a prognostic and/or diagnostic value.

Human parathyroid hormone (1-34) transiently increases the excretion of lysosomal enzymes into urine and the size of renal lysosomes.

It has been reported that the urinary excretion of N-acetyl-beta-D-glucosaminidase (NAG), a lysosomal enzyme, transiently increases in human after treatment with human parathyroid hormone (hPTH)(1-34). We report here that hPTH(1-34) caused transient changes in the size and density of rat renal lysosomes following urinary excretion of NAG and other lysosomal enzymes tested. Percoll density gradient centrifugation revealed that hPTH(1-34) slightly but significantly increased the fraction of high density lysosomes (around 1.12 g/ml) 5-10 min after the treatment with hPTH(1-34), with a concomitant decrease in the fraction of intermediate density lysosomes (1.07-1.08 g/ml). On electron micrographs, some lysosomes in proximal tubules but not in distal tubules showed a change in morphology from circular to oval, and became enlarged and electron-dense 5-10 min after the treatment with hPTH(1-34). These responses to hPTH(1-34) were also reversible and transient. NAG excreted in urine after treatment with hPTH(1-34) had the molecular mass of a mature form in lysosomes and/or endosomes and was not a prepro-and/or pro-form of the enzyme. Thus, the changes in the density and size of renal lysosomes appear to be associated with the exocytosis of lysosomal enzymes by hPTH(1-34).

Alterations of cathepsins B, H and L in proximal tubules from polycystic kidneys of the Han:SPRD rat.

Abnormalities of tubular matrix metalloproteinases have been shown recently to occur early in the course of polycystic kidney disease (PKD). The present study was conducted to determine whether lysosomal cysteine proteinases were altered in proximal tubules from 2-month-old, heterozygous Han:SPRD rats. The activities of cathepsins B (-45%), H (-39%) and L (-37%) were significantly lower in proximal tubules from PKD rats as compared to healthy offspring. Enzyme proteins were also decreased (cath. B, 2.4 +/- 0.7-fold; cath. H, 1.9 +/- 0.6-fold; N = 4, P < 0.05), while mRNA levels for cathepsins B, H and L were not different. Tubular cystatin C, a major inhibitor of cathepsins, was normal with regard to protein and mRNA levels in PKD animals. The decrease in cathepsins in PKD was specific for tubules, as enzyme activities in glomeruli and liver tissue were unchanged and limited to the lysosomal compartment, since marker enzymes for cytoplasm, endoplasmatic reticulum and mitochondria were all normal. Intralysosomally, soluble enzymes like cathepsins and beta-NAG were decreased, while membrane-bound acid phosphatase was unchanged. The presence of cathepsins could be demonstrated in cyst fluid from homozygous PKD rats and urinary excretion of cathepsins was enhanced in heterozygous animals. Taken together, these findings indicate that the reduction in tubular cathepsins B, H and L was neither due to decreased gene expression nor to upregulation of specific inhibitors, but was likely due to enhanced apical secretion of these enzymes.

Levels of urinary cathepsin B-like substance in patients with gynecologic malignancy.

Because certain proteolytic enzymes are thought to be released by malignant cells, we have measured the activity of cathepsin B in the urine samples of 57 patients with gynecologic malignancies and 60 disease-free controls. A unit (U) of enzyme activity is the release of one n-mol of 7-amino-4-fluoromethylcoumarin (AFC) from BZ-val-lys-lys-arg-MNA min-1 ml-1. Units of activity in the malignant group (10.6 +/- 9.8) differed significantly (p less than 0.0001) from controls (2.8 +/- 3.3). Although enzyme activity in both groups correlated with increasing age, the difference between those subjects with malignancies and those with none remained significant (p = 0.049) by analysis of covariance after adjusting for age. There was no correlation between titers and the race or weight of the subjects in either group. Enzyme activity of subjects with malignant disease correlated (p = 0.003) with the clinical stage of disease. Optimum sensitivity and specificity as determined by Receiver Operator Characteristic Analysis with an upper normal level of 5 U were 84.2% and 86.7%, respectively. Our findings suggest that measurement of urinary cathepsin B might be useful in detecting and managing patients with gynecologic tumors.

Molecular forms of beta-hexosaminidase and cathepsin D in serum and urine of healthy subjects and patients with elevated activity of lysosomal enzymes.

A procedure is described that allows the characterization of the molecular forms of beta-hexosaminidase and cathepsin D in controls and pathological specimens of human serum and human urine. The following observations were made. (1) In human serum, beta-hexosaminidase (alpha- and beta-chain) and cathepsin D are present predominantly in their high-molecular-weight precursor forms. In human urine, these enzymes exist as both precursor and mature forms. (2) Cathepsin D precursor from serum and urine differs in the number of oligosaccharides that are sensitive to endo-beta-N-acetylglucosaminidase H. Therefore the urine enzyme is not likely to originate from the serum. (3) The presence exclusively of precursors of beta-hexosaminidase and of cathepsin D in the sera of patients with hepatitis suggests that in hepatitis secretion of lysosomal enzymes is elevated, rather than the enzymes leaking from damaged cells. (4) In the urine of patients with nephrotic syndrome, beta-hexosaminidase and cathepsin D are present in grossly elevated amounts, but do not differ in the polypeptide patterns from controls. (5) In urine from a patient with mucolipidosis II, the elevated activity of beta-hexosaminidase is accounted for mainly by the precursor forms. Mature beta-chain of beta-hexosaminidase is lacking, and incompletely processed beta-hexosaminidase polypeptides are present. Both the precursor and the mature forms of cathepsin D are increased. They contain only complex oligosaccharides.

Effect of chloroquine on the stability of rat kidney lysosomes in vivo and in vitro.

1. Chronic administration of chloroquine to rats results in increased urinary excretion of lysosomal acid phosphatase, muramidase and cathepsin D. 2. Various concentrations of chloroquine caused lysosomal membrane swelling as shown by decrease of light absorbance in lysosomal suspensions. 3. Incubating lysosomal suspensions in the presence of chloroquine resulted in a marked lysosomal acid phosphatase release. 4. Addition of acetylsalicylic acid, a lysosomal membrane stabilizer, into a lysosomal suspension containing chloroquine, reduced the degree of lysosomal membrane swelling and acid phosphatase release. 5. The results suggest a labilizing effect of chloroquine on rat kidney lysosomes.

The role of cathepsin D in pathogenesis of acute post-streptococcal glomerulonephritis.

Cathepsin D activity has been studied by a fluoremetric assay in the urine of acute post-streptococcal glomerulonephritic (APSGN) patients aged from 3 to 14 years and has been found elevated when compared with four groups of controls. This activity cannot be accounted for by erythrocytes and/or leukocytes in the urine of these patients since haematuric and pyuric controls did not exhibit an amount of enzyme activity greater than the normal control group. Cathepsin D activity can be attributed to lysosomal enzymes released from polymorphonuclear leukocytes which are in close contact with glomerular basement membrane. Complement C3 levels in serum and cathepsin D activity in urine of these patients showed no correlation.