Serum level of cathepsin B and its density in men with prostate cancer as novel markers of disease progression

BACKGROUND

Cathepsin B has been shown to play an important role in invasion and metastasis of prostate cancer. The objective of this study was to determine whether serum levels of cathepsin B and its density (cathepsin B-D) could be used as predictors of disease extension as well as prognosis in patients with prostate cancer.

MATERIALS AND METHODS

Serum levels of cathepsin B in 60 healthy controls, 80 patients with benign prostatic hypertrophy (BPH) and 120 patients with prostate cancer were measured by a sandwich enzyme immunoassay. Cathepsin B-D was calculated by dividing the serum levels of cathepsin B by the prostate volume, which was measured using transrectal ultrasonography. We subsequently analyzed the association between these two factors and several clinicopathological factors.

RESULTS

The mean values of cathepsin B and cathepsin B-D in patients with prostate cancer were significantly higher than those in healthy controls and BPH patients. Moreover, the cathepsin B and cathepsin B-D levels in patients with metastasis were significantly elevated compared with those in patients without metastasis. Among patients undergoing radical prostatectomy, the levels of cathepsin B and cathepsin B-D in those with pathologically confirmed extraprostatic disease were significantly higher than in patients with organ-confined disease. However, there was no significant association between the elevation of cathepsin B and cathepsin B-D levels and cause-specific survival in prostate cancer patients.

CONCLUSION

These findings indicate that the elevation of serum cathepsin B and cathepsin B-D could be used as novel predictors of disease extension, but not survival, in patients with prostate cancer.

Serum cathepsin B activity during regression of Morris hepatoma 5123 D

BACKGROUND

Serum cathepsin B activity has been considered a potential marker of tumor progression. We previously demonstrated that low-frequency electromagnetic stimulation (LF EMS), called bioresonance therapy (BRT), may both accelerate and inhibit the growth of transplantable hepatoma (Morris type 5123D), including total tumor regression. The aim of this study was to assess serum cathepsin activity during tumor progression and regression.

MATERIAL/METHODS

Of 60 female rats inoculated with Morris hepatoma cells, 45 were treated with BRT, and the remaining 15 were left without treatment. Fifteen rats without inoculated tumors served as controls. Serum cathepsin B activity was determined, tumor volumes were measured, and histological examinations of the tumor tissues were performed.

RESULTS

Of the 45 BRT-treated rats, tumor regression was observed in 31 rats, and serum cathepsin activity was analyzed in these rats. In all non-treated rats, tumor progression was observed. Serum cathepsin B activity was significantly higher in both the BRT-treated group (27.8+/-4.1 U/l, p<0.01) and the tumor-bearing group (19.9+/-2.5 U/l, p<0.05), as compared to the controls (13.3+/-3.4 U/l).

CONCLUSIONS

Cathepsin B may play an important role, not only in tumor expansion, but also during the processes of cancer cell death and resorption. High circulating levels may thus correspond to effective therapeutic response in the course of antitumor treatment.

The role of cathepsin B and cystatin C in the mechanisms of invasion by ovarian cancer

OBJECTIVE

The aim of this study was to investigate the contribution of cathepsin B and cystatin C to the mechanisms of invasion by ovarian cancer.

MATERIALS AND METHODS

Using surgical materials from patients with ovarian cancer, immunohistochemistry, sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and Western blotting analysis were performed using antibodies against cathepsin B or cystatin C. Serum levels of cathepsin B and cystatin C in patients with benign and malignant ovarian lesions were determined by enzyme-linked immunosorbent assay (ELISA). An invasion assay using an ovarian cancer cell line was performed by addition of cystatin C or specific inhibitors of cathepsin B.

RESULTS

While immunohistochemical staining of cathepsin B and cystatin C was evident in cancer cells and associated stromal tissue, this was not the case in benign tumors. The malignancies were also found to be positive for cathepsin B and cystatin C by SDS-PAGE and Western blotting analysis. No significant difference in serum cathepsin B levels was observed between patients with benign and malignant disease. However, the concentration of cystatin C in cases with ovarian cancer was significantly higher in benign cases (P<0.0001) and in healthy controls (P<0.0001). Invasion by cancer cells was dose-dependently suppressed by cystatin C and cathepsin B inhibitors.

CONCLUSION

The results provided convincing evidence that cathepsin B and cystatin C may contribute to the mechanisms of invasion of ovarian cancer.

[Serum stefin A in patients with type 2 diabetes]

Stefin A is the low-molecular, intracellular inhibitor of the human lysosomal cysteine proteinases, cathepsins B, H and L. The concentration of this inhibitor in plasma and in other biological fluids shows not only local expression and secretion but also immunity of the whole organism. The aim of our study was to examine if concentration of stefin A in plasma of patients with diabetes type 2 is different than in healthy subjects, depends on vascular complications, body mass index, glycaemic control and whether exists the relationship between activities of cathepsin B (CB) as well as N-acetyl-beta-D-glucosaminidase (NAG). In plasma of 62 diabetic patients and 14 control subjects, concentration of stefin A (using ELISA test) and activities of CB and NAG (using fluorescence methods) were investigated. Concentration of stefin A (4.95 micrograms/l) in comparison to control (2.80 micrograms/l) increased statistically significantly (p < 0.05). The highest increase of stefin A was discovered in patients with macrovascular complication (7.70 micrograms/l) and was significantly different (p < 0.01) in comparison with control group and patients with microangiopathy as well as both types of complications (micro- and macroangiopathy). Significantly higher concentration of stefin A was noted in patients with overweight and obesity (5.50 micrograms/l and 6.05 micrograms/l). No influence of glycaemic short and long term control on concentration of this inhibitor was observed. In patients divided into subgroups according to increasing plasma NAG activity, increase of stefin A was noted successively from subgroup K2 to K4 (NAG from 8.80 U/l to above 12.82 U/l). The results indicate contribution of stefin A in pathogenesis of vascular complications in patients with diabetes type 2 and its relationship with obesity.

Regulation of CD18 expression on neutrophils in response to fluid shear stress

When leukocytes adhere to endothelial cells and are exposed to fluid shear stresses, they often retract pseudopods and reduce their attachment. Leukocytes use CD18 for membrane adhesion, but the kinetics of such integrin adhesion molecules under fluid shear is unknown. We examine on neutrophils with confocal microscopy of single adherent cells and flow cytometry of cell suspensions the CD18 expression under fluid shear after labeling with fluorescent antibodies. Fluid shear causes reduction of CD18-associated immunofluorescence of extracellular epitopes, especially in areas of the membrane exposed to elevated levels of shear (1.5 dyne/cm2 maximum shear stress; 1 dyne = 10 mN). CD18 was also translocated over the leukocyte surface from regions of higher shear to lower shear and into the membrane contact areas with the substrate. We obtained no evidence for cytoplasmic internalization of CD18. Fluid shear (5 dyne/cm2) in a suspension of human leukocytes resulted in cleavage of the extracellular domain but not against a cytoplasmic domain of CD18. Chelation of extracellular Ca2+ abolished the down-regulation of CD18. Cysteine protease inhibitors and a selective inhibitor for cathepsin B, but no blockade of other cysteine proteases such as cathepsin L and calpain, aminopeptidases, elastase, or metalloproteinases, suppressed shear-induced CD18 down-regulation. The evidence suggests that physiological levels of fluid shear cause release of cysteine protease(s) including cathepsin B, leading to cleavage of the extracellular domain of CD18 molecules and possible membrane detachment.

Cystatin C and cysteine proteinases during the development and therapy of Lewis lung adenocarcinoma in mice

We measured plasma cystatin C concentration and activity of cathepsins B and L in tumor tissue as possible markers for the efficiency of antitumor therapy and prognostic criteria for Lewis lung adenocarcinoma in mice. Plasma cystatin C concentration markedly decreased in mice with tumors. During successive therapy the increase in plasma cystatin C concentration correlated with the degree of inhibition of tumor growth. Activities of cathepsins B and L in the liver increased in animals with tumors. In mice receiving successive antitumor therapy activities of cathepsins B and L increased in tumor tissue, but decreased in the liver (compared to untreated animals).

[Enzymatic activity of cathepsin B, cathepsin B and L, plasmin, trypsin and collagenase in hepatocellular carcinoma]

Hepatocellular carcinoma is one of the most common malignancies worldwide. Invasiveness of this tumour seems to be related to degradation of extracellular matrix. Such proteolytic enzymes as: cathepsin B and L, plasmin, collagenase and trypsin are thought to play a pivotal role in this process. Enzymatic activity depends on balance between enzymes and their inhibitors and--moreover--on interactions among these enzymes. The purpose of our study was to evaluate enzymatic activity of cathepsin B, cathepsin B and L, plasmin, collagenase and trypsin in patients with hepatocellular carcinoma in liver tissue and in peripheral blood. Then correlations between activity of enzymes (mentioned above) and clinical status, pathological findings and laboratory tests were assessed. Our study was conducted on 14 patients who underwent surgery because of hepatocellular carcinoma. Tissue samples were obtained during surgery from neoplastic area and from non-neoplastic area. Peripheral blood was withdrawn before surgery and within early post-operative period. Proteolytic activity of these enzymes was determined with use of fluorometric assay. Enzymatic activity in tissue samples was referred to protein concentration (BCA assay) and to DNA concentration (fluorometric assay).

RESULTS

Proteolytic activity of plasmin and trypsin in neoplastic tissue were significantly lower as compared to non-neoplastic area of these patients (p = 0.0356; p = 0.0412, respectively). Activity of the remaining enzymes: cathepsin B, cathepsin B and L and collagenase did not differ significantly. No difference was demonstrated between activity of enzymes in peripheral blood withdrawn before surgery and in postoperative period. There was a statistically significant inverse correlation between serum AFP level and enzymatic activity of cathepsin B, cathepsin B and L and collagenase in tumor tissue. Lower activity of all investigated enzymes was observed in tumor tissue of HBV related hepatocellular carcinoma in comparison with the remaining tissue samples. Correlation between patients age and activity of enzymes was not statistically significant.

CONCLUSION

Although the evaluation of presented enzymatic profile did not allow for the assessment of associations between investigated enzymes, our results demonstrated correlations between proteolytic activity of enzymes and serum AFP level, viral status, but it requires further investigations.

Doxorubicin immunoconjugates containing bivalent, lysosomally-cleavable dipeptide linkages

Bivalent doxorubicin (DOX)-dipeptides (16a-c) were prepared and conjugated to the monoclonal antibody BR96. The dipeptides are cleaved by lysosomal proteases following internalization of the resulting immunoconjugates. Conjugate 18b demonstrated antigen-specific in vitro tumor cell killing activity (IC(50)=0.2 microM) that was equipotent to DOX with a near doubling of drug molecules/MAb. Size exclusion chromatography showed 18b to be a noncovalent dimer that was formed immediately upon conjugation.

Isolation of novel peptides, cabin-1, -2, -3, and -4, that inhibit cathepsin B from a thermolysin digest of human plasma

Four novel peptides that inhibit cathepsin B, designated as Cabin-1, -2, -3, and -4, were isolated from a thermolysin digest of human plasma. After gel filtration and cation-exchange chromatography, the peptide mixture was purified by reverse-phase HPLC to isolate Cabin-1, -2, -3, and 4, with the amino acid sequences LGPVTQE, VLQSSGLYS, VVSVLT, and LVYDAY, respectively. These peptides correspond to f(64-70) of human apolipoprotein A-I for Cabin-1, f(56-64) and f(185-190) of the human immunoglobulin G gamma chain for Cabin-2 and -3, and f(66-71) of human transferrin for Cabin-4. Synthetic Cabin-1, -2, -3, and -4 showed dose-dependent inhibition of cathepsin B. Their IC50 values were 450, 500, 20, and 5.0 micromol/l, respectively. Lineweaver-Burk plots suggested that Cabin-3 is a noncompetitive inhibitor, while Cabin-4 is a competitive inhibitor. Among the N- and C-terminal deletion peptides of Cabin-2 and -4, Cabin-2(1-8), VLQSSGLY, was found to have the most potent inhibitory activity, with an IC50 of 3.8 micromol/l.

Cathepsin expression in oral squamous cell carcinoma: relationship with clinicopathologic factors

OBJECTIVE

Proteases are involved in the invasion and metastasis of carcinoma cells. In vivo, oral carcinoma cells easily invade the bone tissue and metastasize to the submandibular and neck lymph nodes. Cathepsin expression has been shown in some neoplastic tissues and serves as a prognostic indicator. The purpose of this study was to investigate the relationship between clinicopathohistologic grades and cathepsin expressions in oral squamous cell carcinoma and to investigate which cathepsin provides prognostic information for patients with oral carcinoma.

STUDY DESIGN

Immunohistochemical studies were performed on 78 carcinoma samples with monoclonal antibodies against cathepsins B, H, and L, and a polyclonal antibody against cathepsin D. Serial sections were stained by hematoxylin-eosin staining and classified by Anneroth's classification. Cathepsin B, H, L and D activities of blood serum were determined. Positive results indicative of the presence of cathepsin were investigated to determine any correlation between a particular cathepsin and histologic malignancy grades, tumor cell growth, serum cathepsin activities, and clinical factors.

RESULTS

Cathepsins B, H, L, and D were positive in every case. Although the labeling indices for cathepsins B (CB-LI), H (CH-LI), and D (CD-LI) for the cancer cases showed significant differences from those of controls, cathepsin L (CL-LI) of cancer cases showed no difference from that of controls (P <.05). A close correlation was found between CD-LI and T categories of TNM classification (P <.05), and between CD-LI and PCNA-LI (P <.05). Furthermore, a close correlation was found between CD-LI and N categories in TNM classification (P <.05). Pathologically, a close correlation was found between CB-LI or CD-LI and the pattern and/or stage of invasion (P <.05).

CONCLUSION

Cathepsin D and B expression were closely correlated with carcinoma invasion and progression. These proteases may be useful in determining the prognoses of patients with oral carcinoma.

Serum concentration and circadian profiles of cathepsins B, H and L, and their inhibitors, stefins A and B, in asthma

BACKGROUND

In order to determine the effect of asthma on serum concentrations of cathepsins B, H and L, and stefins A and B, the circadian and concentration profiles were followed in steroid-independent and steroid-dependent asthmatics before and after 1-week treatment with methylprednisolone and cyclosporin A.

METHODS

Serum samples were taken at 4-h intervals throughout a 24-h period. Cathepsin and stefin concentrations were assayed using specific ELISAs. Data were analysed by one-way ANOVA and least squares fit of 24-h cosine.

RESULTS

Temporal analysis of these proteins revealed little or no significant changes with time over a 24-h period. In comparison to normal sera, cathepsin H concentrations were elevated in all asthmatic patients, concentrations of both stefins were decreased in steroid-independent asthmatics, and stefin A concentrations were increased in steroid-dependent asthmatics before therapy. The effect of methylprednisolone treatment was demonstrated on decreased cathepsin B and increased cathepsin L concentrations in post-therapy serum samples. On the other hand, cyclosporin A treatment led to increased concentrations of cathepsins H and L. However, concentrations of stefins A and B were unaffected.

CONCLUSIONS

This study associated alterations in balance of serum cysteine proteinases and their inhibitors in asthmatic patients, which has raised the possibility of their involvement in asthma pathogenesis. Validated rhythms of cathepsins and stefins in asthmatic sera exhibited temporal differences, which are too small to influence the time of sampling for their quantitative measurement over the course of a day.

Cathepsin B and L and stefin A and B levels as serum tumor markers in squamous cell carcinoma of the head and neck

Cysteine proteinases cathepsin (Cath) B and L and their endogenous inhibitors stefin (Stef) A and B concentrations were measured using a quantitative immunosorbent assay (ELISA; KRKA d.d., Novo mesto, Slovenia) in serum samples from 35 patients with primary and 7 patients with recurrent squamous cell carcinoma of the head and neck (SCCHN), obtained at diagnosis (Serum no.1) and after therapy (Serum no. 2), and compared to sera from 30 (Stef B, 90) healthy volunteers. A significantly higher Stef A (P = 0.005) and lower Stef B (P < 0.001) concentrations were measured in patients' Serum no.1 than in controls, and the levels of Caths B and L and Stef A were found to be significantly elevated in Serum no.1 as compared to Serum no. 2 (P = 0.045, P = 0.041 and P = 0.024, respectively). The time of Serum no.2 collection did not influence the concentration of either Caths or Stefs in these samples, and no correlation was observed with the established prognostic factors for any of the parameters studied. Patients with subsequently diagnosed recurrent disease had a significantly lower Cath L concentration than those without evidence of relapse during follow up (P = 0.05). The risk of disease recurrence and SCCHN-related death correlated significantly with low Cath L serum levels (P = 0.012, P = 0.006). The serum levels of Cath B, Stef A and Stef B did not influence significantly the probability of survival.

Cathepsin B/cystatin C complex levels in sera from patients with lung and colorectal cancer

A sandwich-type ELISA has been developed for quantification of the complex between the cysteine proteinase cathepsin B (CB) and its reversible tight-binding inhibitor cystatin C (CC) in normal and pathological sera. The assay is based on a combination of catching Ab (3E1), raised against CB, and a horseradish peroxidase-labelled detection Ab (1A2), raised against CC. Only the CB/CC complex is able to evoke a signal in this assay. The detection limit of the assay was 15.5 nM and the working range between 31.3-200 nM. The within and between-run coefficients of variance (CV) varied from 4.7% to 9.4% and 11% to 12.8%, respectively, demonstrating satisfactory reproducibility of the method. The concentration of the CB/CC complex was determined in sera from 90 healthy controls, 32 patients with non-cancerous lung diseases, 148 patients with lung and 32 patients with colorectal cancer. The CB/CC complex was significantly less abundant in sera of patients bearing malignant lung tumours than in those with non-cancerous lung diseases or healthy controls (p<0.001). In colorectal cancer sera its level was significantly lower in advanced stages C and D than in early Dukes' stages A and B (p=0.02). Our results show that the increased levels of CB in malignant sera are not impaired effectively by CC and support the hypothesis of hindered inhibitory capability during cancer progression.

Innate immune response mechanisms in non-insulin dependent diabetes mellitus patients assessed by flow cytoenzymology

It is well known that infections in patients with diabetes mellitus are more severe, although there is controversy for increased susceptibility to them. Non-specific immune response mechanisms could be related to defense and/or susceptibility to pathogens. The aim of this study was to investigate the activity of several enzymes involved in the primary host defense mechanisms in non-insulin dependent diabetes mellitus (NIDDM). Twenty NIDDM females with a mean HbA(1c) level of 8.19% were included. No patient had clinical evidence of infection. As controls 20 healthy females were studied. The enzymes tested were dipeptidyl-peptidase I (DPP-I), cathepsin B and D, NADPH oxidase and superoxide dismutase (oxidative burst) and collagenase. Isolated leukocytes were incubated with the specific substrates in pyrogen free conditions. The intracellular enzyme activity was analyzed by flow cytometry. Collagenase enzymatic activity was similar in the three leukocyte subpopulations studied. Oxidative burst induction in monocytes was comparable between both groups. Enzyme activity of cathepsin B and D in all cell subsets, oxidative burst in PMN cells, and DPP-I in lymphocytes and monocytes from patients, was higher than those from healthy females (P<0.05). Overall, our findings demonstrate an enhanced functional status of several intracellular leukocyte enzymes in NIDDM. Furthermore, the increased oxidative burst induction and the consequent production of free radicals, may contribute to vascular complications. Other mechanisms - either from the non-specific or specific immune response - deserve investigation to establish if diabetic patients are more susceptible to infectious diseases.

[Biochemical parameters of the metabolism of the intercellular substance of connective tissue, correlating with morphometric signs of long bone lesions in an open aseptic fracture]

The aim of the research was experimental study of dynamics and correlative dependences between biochemical connective tissue matrix metabolism indices (blood serum collagenase, cathepsin B, elastase, antielastase activity, hydroxyproline fractions and glycosaminoglycans concentration) and tissue damage morphometric indices after long bone aseptic osteotomy of rat in terms 3 h-60 days. The most strong and significant correlation was found between cathepsin B, elastase activity indices and dimensions of bone marrow ischemic damage focuses and summarised periosteal regenerates volume in bone fragments.

Matrix metalloproteinases, but not cathepsins B, H, and L or their inhibitors in peripheral blood of patients with rheumatoid arthritis are potentially useful markers of disease activity

OBJECTIVE

The clinical activity of rheumatoid arthritis (RA) is not reliably reflected by laboratory measures. Proteolytic enzymes involved in the cascade of joint destruction are potentially useful parameters to monitor the extent of joint inflammation in RA. This study compares the validity of two classes of proteolytic enzymes, matrix metalloproteinases (MMP) and lysosomal cysteine proteinases (cathepsin B, H, and L) as well as their respective inhibitors to serve as parameters of RA disease activity.

METHODS

The proteolytic activity of cathepsin B, H, and L was determined by fluorometry in sera of 20 patients with active RA and of 20 healthy donors. In addition, the concentrations of cathepsin B and L as well as of cathepsin inhibitors stefin A, stefin B, and cystatin C were measured by ELISA. The plasma concentrations of MMP-1 (collagenase), MMP-3 (stromelysin), tissue inhibitor of metalloproteinases 1 (TIMP-1), and of MMP-1/TIMP-1 complex (MT complex) were analyzed by ELISA as well.

RESULTS

A significant increase of MMP-1, MMP-3, and MT complex was observed in RA plasma, compared to normal controls, whereas TIMP-1 concentrations did not differ. In contrast, neither serum activity nor protein concentration of any of the cathepsins or cathepsin inhibitors were elevated in RA.

CONCLUSION

Despite ample evidence in the literature that cathepsin activity contributes to the pathogenesis of inflammatory joint disease, this is not reflected by the conditions in peripheral blood. In contrast to the cysteine proteinases, MMP-1 and MMP-3 as well as MT complex are elevated in RA. In the context of findings in the literature, this stresses the importance of MMP as disease activity markers, compared to cysteine proteinases or their inhibitors.

Cathepsin B in human leukocytes

We have applied a method using the fluorigenic substrate benzoloxycarbonyl-Arg-Arg-amido-4-methylcoumarin to measure cathepsin B, a thiol proteinase, in homogenates of human leukocytes. Data like pH optimum, stability, influence of thiol groups and effects of thiol proteinase inhibitors, lack of binding to Concanavalin A and lack of contribution to the fluorescence by other cathepsins indicate that cathepsin B is the enzyme measured. Although the activity of the enzyme was linear with respect to time at all protein concentrations measured, there was an acceptable 10% deviation of the enzyme activity from linearity as a function of protein concentration. The enzyme in the homogenate was stable at 0 degrees C but was rapidly inactivated at 50 degrees C and above pH 6.5-7. Very limited activation on the one hand and variable inhibition on the other was seen by reagents containing thiol groups and thiol proteinase inhibitors respectively. Latency (60% of the enzyme activity) indicates a probable subcellular lysosomal localization. There is no affinity towards the lectin Concanavalin A and the Km value was around 1 mmol/l. Normal enzyme activity values in leukocyte homogenates were determined.

Prognostic values of cathepsin B and carcinoembryonic antigen in sera of patients with colorectal cancer

The level of cathepsin B (Cat B) was determined in sera obtained preoperatively from 325 patients with colorectal cancer using an ELISA. Control sera from 90 healthy blood donors were analyzed. The levels of Cat B detected included all forms that were present in the sera, i.e., mature enzyme, precursor molecule, and enzyme-inhibitor complexes. The level of Cat B was significantly increased in sera of patients with colorectal cancer. The median level was 10.7 ng/ml versus 2.1 ng/ml in controls (P < 0.0001). A correlation between Cat B serum level and advanced Dukes' stage (P < 0.003) was found, whereas no associations have been found with age, sex, or level of carcinoembryonic antigen (CEA). In survival analysis, the patients with high serum Cat B experienced significantly lower survival probability. At the optimal cutoff value of 9.4 ng/ml, the relative hazard ratio was 1.8 (95% confidence interval, 1.1-2.8; P = 0.016) in the univariate Cox proportional hazards model. The median observation time was 4.4 years (range, 3.2-5.5 years). In multivariate analysis, Dukes' stage was the strongest prognostic variable, followed by age, whereas serum Cat B and CEA were not significant prognostic factors in this model, in accordance with their association with Dukes' stage. When the data for Cat B and CEA were combined, CEA-positive patients were further separated by Cat B into high- and low-risk groups. Patients with high serum levels of both molecules had significantly shorter survival (relative hazard ratio of 2.2; 95% confidence interval, 1.5-3.2; P < 0.0001), as compared with patients with low levels of both molecules.

[Dependence of serous activity of cathepsin B on histological types of ovarian carcinomas]

The preoperative activity of cathepsin B was determined in the serum of 110 patients with primary ovarian carcinomas and in 35 women with benign ovarian tumor. The significant increase of cathepsin B activity in ovarian carcinomas is independent of its types in comparison to benign ovarian tumor. The percentage of the results with value above the cut-off values was the highest for serous types of ovarian carcinomas. The dependence between the increase of cathepsin B activity and the FIGO stage of the disease was observed only for serous and endometrioid type of ovarian carcinomas.

Cathepsins B, H, and L and their inhibitors stefin A and cystatin C in sera of melanoma patients

The levels of cathepsins (Cats) B, H, and L and their inhibitors stefin A and cystatin C were determined in the sera of 43 patients with metastatic melanoma, in 54 patients with treated cutaneous melanoma with no evidence of metastatic disease, and in 30 healthy blood donors, using quantitative ELISAs. The levels of Cats B and H and cystatin C were significantly higher within the group of metastatic melanoma patients compared with the healthy controls. The median Cat B was 4.8 versus 3.6 ng/ml (P < 0.013), the median Cat H was 13.7 versus 4.9 ng/ml (P < 0.0001), and the median cystatin C was 470 versus 320 ng/ml (P < 0.02). Cat H was also significantly increased within the group of melanoma patients with no metastasis, with a median of 9.6 ng/ml. Cat B was found to correlate with Cat L (r = 0.36; P < 0.02) and cystatin C (r = 0.41; P < 0.008). The serum level of Cat H was significantly increased in patients showing no response to the chemoimmunotherapy as compared to the level in responders. Metastatic melanoma patients with high contents of Cat B and Cat H experienced significantly shorter overall survival rates than the patients with low levels of each enzyme (Cat B: P < 0.003 and relative risk, 2.5; Cat H: P < 0.006 and relative risk, 2.4, using medians as cutoff values). The other potential factors for prognosis for this group of patients revealed moderate (histological type and age) or no (tumor thickness, sex, and lymph node metastasis) prognostic significance. Similarly, no difference in survival was found for stefin A, cystatin C, and Cat L. These results suggest that the serum levels of Cats B and H could serve as prognostic factors for patients with advanced melanoma.

Cathepsin B-like activity as a serum tumour marker in ovarian carcinoma

Serum cathepsin B-like activity was determined in 75 patients with ovarian carcinomas and in control groups. Ovarian cancers were of FIGO stages I-IV. Control groups consisted of 15 healthy women, 20 patients with myomas of the uterus, and 17 with benign ovarian cysts. Preoperative results showed elevated cathepsin B-like activity in 100% of the patients with ovarian cancers in relation to healthy subjects and patients with myomas, and in 78% in relation to benign ovarian cysts. Cathepsin B activity increased progressively with the FIGO stage of the disease, but the differences among particular stages were not statistically significant. In serous tumours cathepsin activity was significantly higher only in comparison to endometrioid ones (p < 0.001). Antipapain capacity of cystatins in the sera was also determined. No significant correlation between cathepsin B-like, and antipapain activity of cystatins was found. Serum cathepsin B-like activity may be helpful in the preoperative differential diagnosis between ovarian carcinomas and benign ovarian or uterine tumours.

Activity of lysosomal and nonlysosomal proteases and contents of protein and its degradation products in the blood serum of rats with fibrosarcoma induced by methylcholanthrene

Activity of lysosomal and nonlysosomal proteases and contents of protein and its degradation products in the blood serum of rats with methylcholantrene fibrosarcoma were evaluated. Activity of lysosomal proteases and prolidase and prolinase as well in the blood serum of rats with methylcholanthrene tumour did not differ from the activity of these enzymes in the blood serum of control rats. Only the activity of elastase and collagenase in the blood serum of rats with methylcholanthrene tumour especially with tumour of intermediate and big mass was increased. Content of total protein was decreased in the blood serum of rats with tumour of intermediate and big mass and contents of glycoproteins and alfa-amin nitrogen were increased in comparison to the blood serum of control rats.

Lysosomal aspartic and cysteine proteinases serum levels in patients with pancreatic cancer or pancreatitis

Lysosomal cathepsins D (CD), B (CB), and L (CL) serum levels were determined by immunoassays in patients with chronic (CHP) or acute (AP) pancreatitis and in patients with ductal pancreatic carcinoma (DPC) and correlated with some biological and clinical parameters of this tumor. CB serum concentrations significantly higher than those measured in healthy subjects (NS) were observed in CHP, AP, and DPC patients (p < 0.01). However, no significant difference was noted among these groups. Increased CL serum levels were evident only in cancer patients compared to NS, AP, or CHP groups (p < 0.05), while no difference was observed among these groups. Elevated CD serum values were observed in CHP and AP patients compared to healthy subjects or cancer patients (p < 0.01). In cancer patients no correlation between CD, CB, and CL and clinical stage or tumor size was found. However, significant correlations were observed only between serum CD and CA50 (p < 0.02) and between CD and CL (p < 0.05). No further relationship among the biochemical parameters examined was observed. The present data suggest that the different serum patterns of CD, CB, and CL in patients with pancreatitis and pancreatic cancer may be of clinical interest as additional biochemical parameters for the differential diagnosis of these diseases. However, further prospective clinical studies are needed to assess better their potential value as prognostic parameters to identify patients with pancreatitis at increased risk to develop pancreatic cancer.

Lysosomal cathepsins B and L and Stefin A blood levels in patients with hepatocellular carcinoma and/or liver cirrhosis: potential clinical implications

The serum levels of lysosomal cathepsin B and L and Stefin A, an intracellular inhibitor of these proteolytic enzymes, were determined in patients with hepatocellular carcinoma (HCC) and/or liver cirrhosis (LC) and correlated with some clinical and biochemical parameters of these diseases. Cathepsin B serum levels were increased in HCC and in LC patients as compared to normal subjects (p < 0.001). However no difference was observed between HCC and LC groups. Interestingly, a significant relationship was evidenced between cathepsin B serum content and the grade of severity of cirrhosis (r = 0.41; p < 0.001). Cathepsin L was significantly elevated only in sera of cancer patients as compared to normal subjects or LC patients (p < 0.001) and significantly correlated with the number of malignant lesions (r = 0.49; p = 0.001). Stefin A serum levels were increased in HCC and LC patients as compared to healthy subjects (p < 0.02). However, these levels were significantly higher in the LC group as compared to the HCC group (p < 0.05). In cancer patients, a significant relationship was observed between Stefin A serum content and tumor size (r = 0.35; p < 0.05), number of neoplastic lesions (r = 0.556; p < 0.001) and serum alpha-fetoprotein (r = 0.38; p < 0.01). These data suggest that cathepsin B and L and Stefin A may be potentially useful as additional biochemical parameters to monitor the therapeutic response of these diseases to clinical treatments and to identify patients with cirrhosis developing precancerous lesions.