Correlation of tumor cytosol cathepsin D with differentiation and invasiveness of endometrial adenocarcinoma

Cathepsin D in the Tumor Microenvironment of Breast and Ovarian Cancers

Cancer remains a major and leading health problem worldwide. Lack of early diagnosis, chemoresistance, and recurrence of cancer means vast research and development are required in this area. The complexity of the tumor microenvironment in the biological milieu poses greater challenges in having safer, selective, and targeted therapies. Existing strategies such as chemotherapy, radiotherapy, and antiangiogenic therapies moderately improve progression-free survival; however, they come with side effects that reduce quality of life. Thus, targeting potential candidates in the microenvironment, such as extracellular cathepsin D (CathD) which has been known to play major pro-tumorigenic roles in breast and ovarian cancers, could be a breakthrough in cancer treatment, specially using novel treatment modalities such as immunotherapy and nanotechnology-based therapy. This chapter discusses CathD as a pro-cancerous, more specifically a proangiogenic factor, that acts bi-functionally in the tumor microenvironment, and possible ways of targeting the protein therapeutically.

Cathepsin D non-proteolytically induces proliferation and migration in human omental microvascular endothelial cells via activation of the ERK1/2 and PI3K/AKT pathways

Epithelial ovarian cancer (EOC) frequently metastasises to the omentum, a process that requires pro-angiogenic activation of human omental microvascular endothelial cells (HOMECs) by tumour-secreted factors. We have previously shown that ovarian cancer cells secrete a range of factors that induce pro-angiogenic responses e.g. migration, in HOMECs including the lysosomal protease cathepsin D (CathD). However, the cellular mechanism by which CathD induces these cellular responses is not understood. The aim of this study was to further examine the pro-angiogenic effects of CathD in HOMECs i.e. proliferation and migration, to investigate whether these effects are dependent on CathD catalytic activity and to delineate the intracellular signalling kinases activated by CathD. We report, for the first time, that CathD significantly increases HOMEC proliferation and migration via a non-proteolytic mechanism resulting in activation of ERK1/2 and AKT. These data suggest that EOC cancer secreted CathD acts as an extracellular ligand and may play an important pro-angiogenic, and thus pro-metastatic, role by activating the omental microvasculature during EOC metastasis to the omentum.

The Potential Role of the Proteases Cathepsin D and Cathepsin L in the Progression and Metastasis of Epithelial Ovarian Cancer

Epithelial ovarian cancer (EOC) is the leading cause of death from gynecologic malignancies and has a poor prognosis due to relatively unspecific early symptoms, and thus often advanced stage, metastasized cancer at presentation. Metastasis of EOC occurs primarily through the transcoelomic route whereby exfoliated tumor cells disseminate within the abdominal cavity, particularly to the omentum. Primary and metastatic tumor growth requires a pool of proangiogenic factors in the microenvironment which propagate new vasculature in the growing cancer. Recent evidence suggests that proangiogenic factors other than the widely known, potent angiogenic factor vascular endothelial growth factor may mediate growth and metastasis of ovarian cancer. In this review we examine the role of some of these alternative factors, specifically cathepsin D and cathepsin L.

Cathepsin D messenger RNA is downregulated in human lung cancer

OBJECTIVES

Lysosomal proteases cathepsins B and D (CB and CD) play a significant part in cancer progression. For many oncological diseases protein expression levels of CB and CD have been investigated and correlations with tumour characteristics revealed. Meanwhile, there is very little information concerning mRNA expression level.

METHODS

In the present work, data about mRNA levels of CB and CD in human lung cancer was obtained using reverse transcription followed by real-time polymerase chain reaction.

RESULTS

For the first time CD and CB mRNA in human lung cancer tumours was quantified. It was shown that CB and CD mRNA levels do not correlate with any tumour characteristics. However, in most analysed tumours, expression of CD mRNA was downregulated compared with adjacent normal tissue (p <0.0003).

CONCLUSIONS

The data obtained indicate CD mRNA as a potential lung cancer marker.

Lysosomes and lysosomal proteins in cancer cell death (new players of an old struggle)

Death of cancer cells influences tumor development and progression, as well as the response to anticancer therapies. This can occur through different cell death programmes which have recently been shown to implicate components of the acidic organelles, lysosomes. The role of lysosomes and lysosomal enzymes, including cathepsins and some lipid hydrolases, in programmed cell death associated with apoptotic or autophagic phenotypes is presented, as evidenced from observations on cultured cells and living animals. The possible molecular mechanisms that underlie the action of lysosomes during cell death are also described. Finally, the contribution of lysosomal proteins and lysosomes to tumor initiation and progression is discussed. Elucidation of this role and the underlying mechanisms will shed a new light on these 'old' organelles and hopefully pave the way for the development of novel anticancer strategies.

Immunohistochemical evaluation of tissue-specific proteolytic enzymes in adenomas containing foci of early carcinoma: correlations with cathepsin D expression and other malignant features

BACKGROUND

Cathepsin D (CD) is an aspartyl lysosomal protease, and the prognostic value of CD expression has been studied in a variety of tumors, however, its role in early adenocarcinomas remains unclear.

AIM OF THE STUDY

We evaluated the expression of CD in a series of colorectal adenomas with severe dysplasia containing foci of early carcinoma and compared the results to several histopathological and immunohistochemical features.

METHODS

Adenomas were obtained by endoscopic polypectomy from 33 patients. Twenty-four of the 33 adenomas contained well-differentiated adenocarcinomas and nine adenomas contained moderately differentiated adenocarcinomas.

RESULTS

Positive CD expressions were observed in 25% of well-differentiated adenocarcinomas and in 66.7% of moderately differentiated adenocarcinomas (p < 0.05). Of the 12 adenocarcinomas with positive CD expression, four had positive CD expression in their adenomas (p < 0.01), 6 showed positive Ki-67 expression in their adenomas (NS), and 10 had positive p53 expression in their adenomas (p < 0.05). No significant association was seen between the level of CD expression and adenoma size.

CONCLUSIONS

The expression of CD in adenocarcinoma correlated significantly with differentiation, and with the levels of CD and p53 expression in the adenomas of the polyp.

Immunohistochemical evaluation of cathepsin D in normal, hyperplastic and malignant endometrium: correlation with hormone receptor status c-erbB-2, p53, Rb proteins and proliferation associated indices

The immunohistochemical expression of cathepsin D was performed in paraffin embedded tissue from 79 endometrial carcinomas, 35 cases of hyperplasia, and 32 normal endometrium using the streptavidin-biotin method to investigate the role of cathepsin D (CD) in these lesions and its possible relationship with other potential and established prognostic markers. The association between CD and the other markers was assessed by univariate analysis. Tumor cell CD expression was lower in the group of carcinomas compared to the normal proliferative (P = 0.022) and secretory endometrium (P = 0.0005). In addition, hyperplastic cell CD expression was lower compared with epithelial cell CD expression in the secretory phase of normal endometrium (P = 0.009). Malignant cell CD expression was inversely correlated with tumor stromal cells (P = 0.007). A positive relationship of stromal cell CD expression with pRb (P = 0.046) and PCNA score (P < 0.0001) was detected in the group of carcinomas. In the proliferative phase of normal endometrium, epithelial CD expression was positively correlated with estrogen status (P = 0.015). The data show that down-regulation of CD expression is an early event in endometrial carcinogenesis. In addition, stromal cell CD expression may be involved in cell growth process in endometrial carcinomas.

Cathepsin D expression in normal, hyperplastic and malignant endometrial tissue: an immunohistochemical analysis

Cathepsin D (CathD), a lysosomal aspartyl protease secreted by normal and malignant cells, is considered to be involved in breakdown of the extracellular matrix. Aim of the present study was to determine the frequency and tissue distribution of CathD in normal, hyperplastic and malignant endometrium. Paraffin-fixed endometrial tissue was obtained from premenopausal women in the proliferative phase (n = 5), early secretory phase (n = 4) and late secretory phase (n = 4) as well as glandular-cystic hyperplasia (n = 5), endometrial polyps (n = 5), endometrial polyps from the use of tamoxifen (n = 5), adenomatous hyperplasia (AH) grade I (n = 5), grade II (n = 4), grade III (n = 5) and endometroid adenocarcinoma (n = 5). CathD expression was evaluated with the IRS score and ANOVA analysis was used for statistical evaluation. CathD was primarily localised in luminal and glandular epihelium with little staining in stromal cells. The expression of CathD was significantly higher during the late secretory phase than in the proliferative phase. Highest expression of CathD was observed in the late secretory phase and in glandular-cystic hyperplasia, whereas endometroid carcinoma showed no expression. A continuous increase in CathD expression was observed in AH, with a significant difference between AH grade I and III. In conclusion, CathD was found to be expressed in normal and hyperplastic endometrial tissue. CathD immunostaining in normal endometrial glands varied on the basis of the phase of the menstrual cycle, suggesting physiological functions of CathD in endometrial maturation and degradation. Adenocarcinomas did express significant lower amounts of CathD. Therefore, the prognostic value of this parameter remains uncertain. A continuous increase in CathD immunostaining was observed in AH. Since AH grade III can be considered as a precursor of endometrial cancer, CathD could be a possible parameter for assessing malignant transformation.

Expression of the protease inhibitor antileukoprotease and the serine protease stratum corneum chymotryptic enzyme (SCCE) is coordinated in ovarian tumors

We have previously reported that the stratum corneum chymotryptic enzyme (SCCE) is overexpressed in ovarian cancers and that SCCE has potential as a useful marker and/or a therapeutic target for ovarian carcinoma. Antileukoprotease (ALP) has been shown to be a specific inhibitor of SCCE. The objective of this study was to investigate the potential cotranscription and overexpression of ALP in carcinoma of the ovary. The expression of ALP transcript was evaluated by Northern blot hybridization and by semiquantitative polymerase chain reaction (PCR) technique. The presence of the ALP protein in ovarian tumor cells was evaluated by immunohistochemistry. Northern blot hybridization showed that the ALP transcript was abundant in ovarian carcinomas but was not detected in the normal ovary. Semi-quantitative PCR examination revealed that the mRNA level of ALP was significantly elevated in low-malignant-potential tumors and in ovarian carcinomas compared with that in normal ovaries (P < 0.01). There was significant positive correlation between SCCE and ALP mRNA overexpression status in ovarian tumor cases (P < 0.01). Immunohistochemical expression of ALP protein was observed in ovarian tumor cells, whereas little or no staining was observed in normal ovarian surface epithelium. Like SCCE, ALP is highly overexpressed in ovarian tumor cells, which begs the question of whether it remains an effective inhibitor of SCCE or whether it is discordant in time or space and is ineffective as an inhibitor of the SCCE enzyme.

May cathepsin D immunoreactivity be used as a prognostic factor in endometrial carcinomas? A comparative immunohistochemical study

OBJECTIVE

To investigate the prognostic value of immunohistochemical detection of cathepsin D and the association between cathepsin D and established prognostic factors in endometrial carcinoma.

METHODS

Cathepsin D immunoreactivity was determined by an immunohistochemical technique in a series of 79 patients with surgical stage I-III primary endometrial carcinoma.

RESULTS

Of 79 tissue specimens, 48 (61%) showed a positive reaction for cathepsin D. A significant correlation between cathepsin D and histological grade was found (P < 0.05). The other established clinicopathological prognostic factors were not associated with cathepsin D. There was not any significant difference in prognosis between the positive cases and negative cases for cathepsin D (P > 0.05). In the univariate analysis cathepsin D immunoreactivity did not show significant prognostic value for overall survival (P > 0.05). The multivariate analysis also showed that cathepsin D was not related to patient outcome (P = 0.24, relative risk = 0.34, 95% confidence interval = 0.05-2.09).

CONCLUSIONS

Our results suggest that cathepsin D immunoreactivity may not be of prognostic value but more studies are needed to evaluate the relationship between its immunoreactivity in tumor cells and in other cells.

Increased concentrations of cathepsin D in peritoneal fluid from women with endometriosis

To assess the release of the proteolytic enzyme cathepsin D in endometriosis, concentrations in peritoneal fluid and serum were measured by ELISA in 54 women with (n = 33) and without (n = 21) endometriosis. Surgery was scheduled in either the proliferative or secretory phase of the menstrual cycle. The concentrations of cathepsin D in the peritoneal fluid were markedly elevated in the endometriosis patients (median 58 ng/ml, interquartile range 0-166 ng/ml) as compared to the controls (5 ng/ml, 0-86 ng/ml), especially in women with late stage disease (n = 19, stages III/IV) and in those not undergoing gonadotrophin-releasing hormone (GnRH) agonist therapy (n = 15). No significant difference was determined in cathepsin D concentrations of the serum from women with and without endometriosis. We conclude that cathepsin D is an important factor that may contribute to the pathogenesis of endometriosis, possibly by promoting digestion of extracellular matrix proteins. These results have implications for the therapeutic efficacy of GnRH agonists.

Low levels of cathepsin D are associated with a poor prognosis in endometrial cancer

Total cytosolic cathepsin D (Cat D) levels were estimated by an immunoradiometric assay in a series of 156 consecutive patients with surgical stages I-III primary endometrial adenocarcinoma. Simultaneously, the tissue content of both oestrogen (ER) and progesterone (PR) receptors, and p185HER-2/neu, DNA content (ploidy), and the fraction of S-phase cells (S-phase) were also estimated. Tumoral Cat D content ranged from 0 to 243 pmol mg(-1) protein (median 44 pmol mg(-1) protein) and was not associated with any of the established clinicopathological and biological prognostic variables, with the exception of a weak positive correlation with the tumoral p185HER-2/neu levels. Univariable analysis performed on a subset of 97 patients, followed for a minimum of 2 years or until death, showed that patient age at diagnosis, high histological grade, advanced surgical stage, vascular invasion, positive peritoneal cytology, low levels of Cat D, negative ER and PR status, aneuploidy, and high S-phase were predictive of the presence of persistent or recurrent disease. However, multivariable analysis revealed that only histological grade, surgical stage, Cat D and PR were significantly associated with the patient's outcome. From these findings, we conclude that Cat D is an independent prognostic factor in endometrial adenocarcinoma, its low levels being associated with a worse clinical outcome.

Effect of procathepsin D and its activation peptide on prostate cancer cells

Cathepsin D, a lysosomal aspartic proteinase, is secreted in the form of enzymatically inactive precursor in some cancer cells. This precursor, called procathepsin D, was found to exhibit growth factor activity toward breast cancer cell lines and this activity was later shown to be mediated by its activation peptide. In the present investigation we have used human procathepsin D and a synthetic 44 amino acid peptide corresponding to the activation peptide of procathepsin D to test its growth factor activity for human prostate cancer-derived cell lines PC3, DU145 and LNCaP. We have tested the level of proliferation of these cell lines depending on the presence of either procathepsin or activation peptide in the medium. In parallel, we have also measured the time dependency of this growth and established the optimal dose of activation peptide. These findings represent the first experimental data showing the direct effects of procathepsin D on prostate cancer cells.

Endometrial carcinoma: immunohistochemically detected proliferation index is a prognosticator of long-term outcome

AIM

To test which immunohistochemically detected tumour parameters are predictive of outcome in endometrial carcinoma.

METHODS

A retrospective study of 300 patients diagnosed with endometrial carcinoma between 1980 and 1985, ensuring a follow up of at least 10 years. Paraffin wax embedded tissues from 236 patients with endometrial carcinoma were evaluated in terms of histological tumour type and grade, stage of disease, and certain immunohistochemical biological parameters. These parameters included the expression of oestrogen and progesterone receptors, the expression of p53 protein, the expression of the c-erbB-2 oncoprotein, and the expression of protease cathepsin D, together with the rate of cell proliferation.

RESULTS

Using univariate analysis, the following parameters correlated significantly with adjusted survival: histological type (p = 0.025), grade (p = 0.00003), FIGO stage (p < 0.00001), proliferation rate (p = 0.00002), oestrogen receptor expression (p = 0.007), progesterone receptor expression (p = 0.0092), and p53 expression (p = 0.00028). These parameters also correlated significantly with both disease free and overall survival. There was a weak correlation of cathepsin D expression with survival, but no correlation of c-erb B-2 expression with survival. Using multivariate analysis, only FIGO stage (p = 0.0021), histological grade (p = 0.005), and proliferation rate (p = 0.0007) remained statistically significant prognosticators of adjusted survival as well as of disease free and overall survival.

CONCLUSIONS

In addition to conventional histological parameters, the immunohistochemical determination of proliferative activity could contribute to the identification of a high risk subgroup of endometrial carcinomas. The other parameters tested were not of significant additional predictive value.

An immunohistochemical assessment of cathepsin D in gastric carcinoma: its impact on clinical prognosis

BACKGROUND

In the context of tumor-associated proteolysis, the prognostic value of cathepsin D in breast carcinoma has been studied but its role is controversial in relation to gastrointestinal carcinoma. The aim of the current study was to determine whether cathepsin D is a prognostic parameter for gastric carcinoma, and also to consider interaction with the urokinase-plasminogen activator (uPA) system as an established risk factor for tumor-associated proteolysis.

METHODS

In a consecutive prospective series of 203 gastric carcinoma patients, expression of cathepsin D in tumor cells was semiquantitatively analyzed with immunohistochemistry (scored 0-3). Median follow-up time was 31 months (range, 9-56 months). Kaplan-Meier (log rank) and multivariate Cox analyses were used to analyze survival.

RESULTS

Kaplan-Meier analysis (log rank statistics) revealed significant association of increasing cathepsin D detection with poorer disease free survival (P = 0.0042) and poorer overall survival (P = 0.0018) of curatively resected patients. Overall survival of all patients was not significantly correlated. Multivariate analysis of established risk factors for gastric carcinoma, including the uPA system, identified cathepsin D as a new and independent prognostic parameter for disease free survival (P = 0.020; relative risk, 2.98; 95% confidence interval, 1.28-6.91). Plasminogen activator inhibitor type-1 as a representative of the uPA system was confirmed as a strong independent factor for disease free and overall survival. Chi-square analysis showed significant correlation of higher cathepsin D levels with Laurén's diffuse-type carcinomas and strong evidence of uPA receptor in tumor cells. However, a subgroup analysis performed according to Laurén's classification revealed a univariate prognostic impact of cathepsin D on both diffuse and intestinal types without independent value. For patients with high levels of uPA receptor (scores of 2 and 3, n = 132), a highly significant association of increasing evidence of cathepsin D with disease free survival (P < 0.0001) and overall survival (P < 0.0001) was observed for curatively resected patients. Significant association with survival was also observed for all patients (P = 0.0407).

CONCLUSIONS

Cathepsin D is a new functional prognostic parameter for gastric carcinoma patients with independent value for disease free survival. Moreover, this study indicates that consideration of more than one tumor-associated protease could lead to a more individualized estimation of risk for carcinoma patients.

Cathepsin B and Cathepsin D Expression in Follicular Adenomas and Carcinomas of the Thyroid Gland

Biologic features that distinguish follicular adenomas (FAs), minimally invasive follicular carcinomas (MICs), and extensively invasive follicular carcinomas (EICs) of the thyroid gland are not well understood. Endogenous proteases, including cathepsin B (CB) and cathepsin D (CD), have been linked to tumor progression in other malignancies and may be important in the different biologic behavior of these follicular thyroidal lesions. Archival paraffin-embedded tissue sections from 16 FAs, 12 MICs, and 4 EICs were studied for immunohistochemical expression of CR and CD. Percent of tumor staining, intensity of staining, and intracytoplasmic staining pattern were assessed. Increased intensity of staining with CD was observed in follicular carcinomas compared to adenomas and was greatest in the EIC (p < 0.04). An increase in diffuse cytoplasmic staining pattern with CD (p < 0.008) and CB (p < 0.02) was observed in follicular carcinomas compared to FAs. The increased intensity of staining with CD in the follicular thyroid carcinomas and the increased diffuse cytoplasmic staining pattern with CD and CR in these carcinomas suggest that these proteinases may play a role in their propensity to invade and metastasize and, therefore, their more aggressive behavior. Furthermore, this diffuse cytoplasmic staining suggests an altered intracellular processing of these proteinases in the carcinomas.

Analysis of cathepsin D from breast tissues by capillary electrophoresis

A rapid and simple method for analyzing cathepsin D in breast tissue based on capillary zone electrophoresis (CZE) is described. After incubating the tissue extracts with hemoglobin as a substrate, a specific peptide is cleaved and separated by CZE in less than 5 min. This peptide is not produced by the action of pepsin or trypsin. It is inhibited by the addition of pepstatin, a specific inhibitor for cathepsin D. Human hemoglobin acted as a better substrate than bovine hemoglobin. The test compared well to a radioimmunoassay. We have shown that peptides can be stacked by the use of acetonitrile. The method demonstrates the advantages of CZE for assay of proteolytic enzymes in general.

Evaluation of the prognostic significance of cathepsin D, epidermal growth factor receptor, and c-erbB-2 in early cervical squamous cell carcinoma. An immunohistochemical study

BACKGROUND

This study evaluated the prognostic significance of immunohistochemical staining for cathepsin D, epidermal growth factor receptor (EGFR), and c-erbB-2 in patients with early cervical squamous cell carcinoma.

METHODS

This retrospective analysis comprised 132 patients, all subjected to radical hysterectomy with bilateral pelvic lymphadenectomy for International Federation of Gynecology and Obstetrics (FIGO) Stage IB cervical squamous cell carcinoma. Immunohistochemical staining was correlated with various histopathologic and morphologic characteristics (i.e., tumor size, grade of differentiation, vessel invasion, invasion into parametria, and lymph node metastasis) and relapse free survival.

RESULTS

Positive staining for cathepsin D was observed in 47% of tumors, more frequent in tumors giving rise to lymph node metastases. The relapse free survival was lower for patients with cathepsin D positive tumors. Overexpression of EGFR was observed in 25.8% of the tumors. There was no correlation with any of the histopathologic variables investigated. Relapse free survival was lower for patients with tumors overexpressing EGFR. Immunohistochemical staining for c-erbB-2 was observed in 12.1% of tumors with no correlation with relapse free survival. In multivariate analysis, immunostaining of cathepsin D and EGFR obtained independent prognostic significance, and considered together (both negative, one positive, or both positive) was the strongest prognostic factor after tumor size.

CONCLUSIONS

Immunohistochemical staining for cathepsin D and EGFR is useful as a tool for evaluation of tumor aggressiveness in patients with early cervical squamous cell carcinoma.

Cathepsin D serum mass concentrations in patients with hepatocellular carcinoma and/or liver cirrhosis

Cathepsin D serum mass concentrations were determined by enzyme immunoassay in patients with hepatocellular carcinoma (n = 51) and/or liver cirrhosis (n = 92) or benign steatosis (n = 16) and correlated with some biochemical and clinical properties of these diseases. Increased cathepsin D serum mass concentrations (P < 0.001) were observed in all these groups of patients as compared to normal subjects (n = 98). However, patients with steatosis had serum mass concentrations of this enzyme significantly lower (mean 2-3 fold) than those measured in cancer patients (P < 0.05) or cirrhotic patients (P < 0.001). Interestingly, significantly higher cathepsin D serum mass concentrations (mean + 62%) (P < 0.006) were determined in the cirrhosis group as compared to cancer patients. No correlation between cathepsin D and a number of clinical and biochemical properties examined, namely, alpha-foetoprotein, number of neoplastic lesions and tumour size in cancer patients or, Child-Pugh grade of severity of cirrhosis and other enzymes of liver function tests in the cirrhotic group was found. The present data and those from other studies which indicate that cathepsin D may be involved in carcinogenesis suggest that this enzyme may be potentially useful as an additional biochemical marker to identify cirrhotic patients who may develop precancerous hepatic nodules.

Lysosomal protease cathepsin D is a prognostic marker in endometrial cancer

The present study investigates the prognostic value of immunohistochemically detected cathepsin D expression in endometrial adenocarcinoma. Patients with surgically treated endometrial adenocarcinoma FIGO stages I-III and consecutive irradiation therapy were included in the study. When we performed immunohistochemistry to detect cathepsin D in 115 tissue specimens 35 cases showed a positive reaction. In the univariate analysis cathepsin D expression showed significant prognostic value for overall survival (P-value = 0.007). In the multivariate analysis with established prognostic parameters (stage, grade) we found an independent prognostic value for cathepsin D (P-value = 0.002, relative risk = 3.8, 95% confidence interval 1.4 - 10.0). Immunohistochemical detection of cathepsin D could aid in predicting prognosis and planning therapy for patients with endometrial adenocarcinoma.

Quantitative analyses of epidermal growth factor receptors, HER-2/neu oncoprotein and cathepsin D in nonmalignant and malignant uteri

BACKGROUND

Hormone receptors and oncoproteins are receiving increased attention as possible prognostic factors in different carcinomas. Few data are available regarding quantification of their levels of expression in gynecologic malignancies.

METHODS

Epidermal growth factor (EGF) receptor specific binding capacities and affinities were measured by ligand binding assay using [125I]EGF in a competition mode with Accufit software (Lundon Software, Inc., Middlefield, OH). HER-2/neu oncoprotein was extracted from membranes and measured using an enzyme-linked immunosorbent assay. Cathepsin D was measured by an immunoradiometric assay using cytosols for steroid receptor analyses.

RESULTS

EGF receptors in 23 nonmalignant uteri ranged from undetectable to 50 fmol/mg membrane protein (median, 0), with dissociation constant values of 1.2 x 10(-9) M to 8.5 x 10(-10) M, compared with EGF receptors in 76 endometrial cancers that ranged from undetectable to 7674 fmol/mg (median, 52). HER-2/neu oncoprotein ranged from undetectable to 2.9 HER-2/neu units (HNU)/microg protein (median, 0.6) in 41 nonmalignant uteri and from undetectable to 5.8 HNU/microg protein (median, 2.5) in endometrial cancers (n = 53). Cathepsin D ranged from 5 to 32 pmol/mg cytosol protein (median, 11) in 42 nonmalignant uteri and 18 to 144 pmol/mg protein (median, 42) in 29 endometrial cancers.

CONCLUSIONS

Determination of the frequency and levels of EGF receptors, HER-2/neu protein, and cathepsin D in uteri with and without cancer and the availability of reference materials developed in our laboratory, will allow evaluation of their prognostic value in cancers of the uterus.

Bone Hemangioendothelioma: An Immunohistochemical Study Related to Histological Malignancy and Proliferative Activity (NORs)

Aims and Background

Forty-four bone hemangioendotheliomas (HEs) of different histological grades were studied to evaluate the expression and distribution of laminin, type IV collagen, cathepsin G and cathepsin D in cell differentiation and malignancy.

Results

In poorly-differentiated HEs the discontinuous distribution of laminin and type IV collagen around angioblastic cords, tubes and cavities revealed an irregular and disorganized basement membrane (BM) architecture corresponding to an increased cell proliferation and secretion of cathepsin D and cathepsin G by tumor cells.

Conclusions

The mean nucleolar organizer region (NOR) area, as a measure of cell proliferation, was significantly higher in grade 4 malignancies than in lower grades, revealing novel prognostic parameters.

Comparison of cathepsin D determinations in human carcinomas by enzyme immunoassay and immunoradiometric assay

Overexpression of cathepsin D in several types of carcinoma in women appears to be associated with a poor clinical course. In this prospective investigation, cathepsin D levels in 170 specimens of normal and neoplastic human tissues were determined simultaneously by enzyme immunoassay (EIA) and immunoradiometric assay (IRMA) to allow comparisons in multicentric studies, such as cooperative clinical trials. Nonmalignant uteri and specially prepared reference powders were also evaluated. Linear regression analysis between the two assays for all specimens [EIA = 0.87(IRMA)-3.18] demonstrated a correlation coefficient (r) of 0.99 (P < 0.001). When malignancies were categorized by the tissue origin (i.e., breast, uterus, ovary, lymph node, and colon), highly significant correlations were also observed (regressions slopes ranged from 0.58 to 1.02). Intra- and interassay controls conducted for the new EIA procedure gave CV% ranging from 4.4 to 10.2, which was similar to the IRMA test for cathepsin D. The results of both assays correlated well and were highly reproducible. Either assay may be used with confidence that comparable cathepsin D values will be obtained in a wide range of tissue biopsies.

Relationship between cathepsin D and other pathological and biological parameters in 1752 patients with primary breast cancer

The relationship between cathepsin D and other pathological or biological prognostic parameters has not yet been defined through systematic studies in breast cancer. The aim of the present investigation was to define the relationship between cathepsin D and nodal status, tumour size, steroid receptors and tumour grade in a wide patient series. Cytosol cathepsin D was assayed with an immunoradiometric assay in tumour samples from 1752 patients. A statistically significant, but not biologically meaningful association was found between cathepsin D and both tumour size and grade. Cathepsin D was significantly higher in node-positive than in node-negative tumours. However, cathepsin D is not of great use in order to predict the risk of axillary metastases in individual patients, due to overlapping of cathepsin D values between node-positive and node-negative cases. A significant, direct association was found between cathepsin D and both oestrogen receptor and progesterone receptor cytosol levels. Nevertheless, preliminary data indicate that cathepsin D and steroid receptors provide independent prognostic information.