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Recent studies suggest that aspartic proteinase Cathepsin D may be implicated in the process of tumor invasion and metastasis. In fact several in vitro observations showed that this proteinase may facilitate the spread of neoplastic cells through different mechanisms related to its proteolytic activity by acting at different levels of the metastatic cascade. Cathepsin D may promote tumor cell proliferation by acting as an autocrine mitogen through the activation of latent forms of growth factors or by interacting with growth factor receptors. The enzyme was also shown to be able to degrade in vitro extracellular matrix and to activate latent precursors forms of other proteinases involved in the invasive steps of the metastatic process. Although unequivocal proof of its active role in promoting these processes also in vivo has not been obtained so far recent clinical observations which showed a positive correlation between level of expression of Cathepsin D activity and malignant progression of some human neoplasms further support this hypothesis. These findings warrant extensive experimental and clinical studies to better assess the pathophysiological role of this acid proteinase in the spread of neoplastic diseases and suggest new and more selective therapeutic approaches to the treatment of human neoplasms.

To assess estrogen and progesterone receptor presence in human breast tumors using immunocytochemical analysis.For both estrogen (ER) and progesterone (PR) receptor assay, percent of stained cells and intensity of staining were estimated on a series of 251 consecutive breast cancer cases from the M. Ascoli Cancer Hospital Center in Palermo using the CAS 200 image analysis system.Cytochemical assay revealed a differential distribution of both ER and PR, by menopausal status of the patients; premenopause (PreM) was mostly ER negative (63%), and postmenopause (PostM)10 years was mostly ER and PR positive (64%). The percent of cells stained for ER was significantly different between PreM and PostM patients when they were considered as a whole. By contrast, no difference emerged for PR staining among menopausal groups. Overall, patients whose tumors were PR positive showed a significantly (P.03) longer interval free of relapse.The present results suggest that PRs behave as better indicators than ERs of early relapse in breast cancer patients. Further studies, with longer follow-up, are needed, however, to validate this concept.

Failure to perform the Fas-related apoptosis pathway can account for tumor resistance both to chemotherapeutic agents and to immunological effectors. We studied the role of NK-kappaB in Fas-resistance, employing the Fas-sensitive human T-lymphoma HuT78 cell line and its Fas-resistant variants HuT78B1 and HuT78G9. All these cell lines expressed high levels of constitutively activated NF-kappaB. Pretreatment of cells with NF-kappaB inhibitors (PDTC, MG132, or SN50) strongly enhanced CH11-induced apoptosis in HuT78 and Hut78G9 cells, while only MG132 showed a similar potentiating effect in HuT78B1. The described synergism was significantly inhibited by pretreatment with the anti-Fas-blocking antibody ZB4 or with the pancapsase inhibitor Z-VAD-FMK, but not by capsase-8 or -9 inhibitors. Overall, these data suggest that NF-kappaB inhibition may restore the Fas-pathway in Fas-resistant NF-kappaB-overexpressing tumors.

Breast cancer is a heterogeneous disease, so therapeutic predictive biological markers need to be identified. To date an accurate evaluation of predictive markers is mainly done at the primary site; however, the main goal of adjuvant therapy for breast cancer is the control of micrometastases. The aim of this study is to assess as therapeutic and/or prognostic marker, the proliferation status of primary tumors and involved nodes as measured by Ki67 and thymidylate synthase (TS) expression, in 30 breast cancer node positive patients. TS is the main target of 5-fluorouracil (5-FU) activity, and its overexpression is one of the mechanisms of 5-FU drug resistance; however, in some studies its absence is responsible for a worse response to 5-FU. Our results show that malignant cells of involved nodes were in a post mitotic phase of the cell cycle, and show a low proliferation index and TS expression, while the primary tumours and controls, were strongly positive. On these basis we can hypothesize that these cells could be less sensitive to 5-FU. Further studies are necessary to identify other mechanisms responsible for their metastasing capability and/or for their aggressiveness.

5-Fluorouracil (5FU) is the main drug used for the treatment of colorectal cancer (CRC) and Thymidilate Synthase (TS) is its target enzyme. TS gene has regulatory tandemly repeated sequences in its 5'' and 3''untraslated region (5''-3'' UTR). CRC often shows a kind of genomic instability called Microsatellite Instability (MSI) that is associated with TS levels and survival. Our data show that the genotype 2R/2R (homozygosity for 2 tandem repeat sequences in the 5''UTR) is more frequently associated with MSI+ and lower TS levels. More over we did not find any significant association between the 2R/3R (heterozygosity for 2 and 3 tandem repeat sequences in the 5''UTR) and 3R/3R (homozygosity for 3 tandem repeat sequences in the 5'' UTR) genotypes with the MSI+ and MSI-, while these genotypes were associated with a higher TS expression. As a consequence we can hypothesise that patients bearing CRC with the MSI+, the 2R/2R genotype and with low TS levels could have a better prognosis and they could not be drug resistant.

Thymidylate Synthase (TS) is the key enzyme for DNA synthesis pathways and is inhibited by 5-fluorouracil (5FU). The aim of this work was to study TS expression and the proliferation rate in the different histological types of colorectal carcinoma (CRC). 50 patients with CRC were included in this study and evaluated immunohistochemically using the monoclonal antibodies, TS106 and Ki67. 20 tumours were of the intestinal type, 15 cases were signet ring cell carcinoma (SRCCs) and 15 cases were "mixed-type", with at least two different histological components. Intestinal and mucinous histotypes were positive for TS and Ki67, while "signet ring cell" samples were negative or showed only weak and focal positivity for both the TS and Ki67 antibodies. Our results show that signet ring cells (that are also often present in intestinal and mucinous carcinomas), are in the post-mitotic phase of the cell cycle and show a low proliferation index and TS expression. As TS is the key enzyme for DNA synthesis pathways and is inhibited by 5-fluorouracil (5FU), we can hypothesise that TS expression levels in the different histotypes of CRC could affect the potential responsiveness of these tumours to fluoropyrimidine chemotherapy, with a low efficacy being expected in signet ring cell areas.

In our study, 72 SCLC patients, 23 with limited and 49 with extensive disease, were treated with carboplatin, epirubicin, and VP-16 (CEV) chemotherapy (CBDCA 300 mg/m2 day 1, EDX 50 mg/m2 day 1, VP-16 100 mg/m2 i.v. days 1-3, every 4 weeks). Patients with limited disease were also subjected to concurrent "split-course" chest radiotherapy followed by surgery in responders if they were not staged IIIB at diagnosis. In limited disease we obtained 96.5% objective responses (OR) with 52.5% complete responses (CR), a median survival of 14 months, with 13% long-term survivors at 30 months. In extensive disease we obtained 83.6% OR with 28.5% CR, and a median survival of 10 months. Toxicity consisted mainly of manageable myelosuppression, especially for limited disease. These data show high activity of CEV chemotherapeutic regimen.

This study was carried out to evaluate the influence of long-term treatment with doxorubicin (DXR) (4mg/kg IV for 5 weeks) on heart and liver lysosomes of mice. We evaluated the variations in both total and "sedimentable" enzyme activity of cathepsin D, which is the major endopeptidase of myocites and probably involved in physiologic and pathologic degradation of actomyosin and mitochondria, and that of acid phosphatase, which is more prominent in interstitial cells. Our results show that marked changes occur in both total and sedimentable enzyme activity of cathepsin D in the heart of treated animals and to a lesser extent in the liver. In contrast, no modification of either total or sedimentable acid phosphatase was seen in either organ. The effects we observed are much more marked for cardiac cathepsin D; this is in good agreement with the cardiac specificity of DXR-induced cardiotoxicity with long-term administration and suggests that lysosomes could play a role in the pathogenesis of this phenomenon. © 1985 Springer-Verlag.

Some haematic parameters were investigated in female COBS mice treated with 7 alpha, 17 beta Dimethyltestcsterone (DMT). The drug causes an increase of circulating platelets in normal mice. Bone marrow graft from DMT-treated donors facilitates in irradiated mice repopulation of white blood cells and platelets but lowers % survival. These data are interpreted on the basis of a commitment and a loss of self-maintenance induced by DMT on CFUs compartment. © 1979 The Italian Pharmacological Society.

In previous studies we reported that teniposide (VM26) induced acute cardiac effects in dogs seem to be related to a release of histamine and that a prior treatment with chlorpheniramine, an H, histamine blocker, prevents the onset of this phenomenon. Since histamine and other vasoactive substances also seem to be involved in doxorubicin (DXR)-induced acute cardiac effects, experiments were undertaken in the aim to prevent, as in the case of VM26, the onset of this phenomenon by administering chlorpheniramine. Since DXR-induced chronic cardiomyopathy also seems to be related to the same mechanisms involved in the onset of acute cardiac effects induced by this drug, additional studies were carried out to investigate whether a long-term treatment with VM26 could induce in mouse alterations of cardiac morphology similar to those of DXR. In addition, because the mouse is known to be extremely insensitive to histamine, further studies were performed to investigate whether DXR or VM26 administration could induce in this animal model a massive histamine release and whether a long-term treatment with high doses of histamine could elicit, similarly to DXR, alterations in cardiac morphology. The results of our experiments demonstrated that DXR (1.5 mg/kg i.v.) caused in the dog a massive histamine release and a marked impairment of cardiac inotropism. As previously described for VM26, prior treatments with chlorpheniramine completely prevented this phenomenon. Furthermore, DXR administration, at a dose level able to induce cardiac damage in the mouse (2.5 mg/kg i.v.), or that of VM26 (2 mg/kg i.v.) failed to induce a massive histamine release. In addition, long-term treatment with VM26 (2 mg/kg i.v.) or high doses of histamine (100 mg/kg i.v.), unlike DXR, did not elicit in this animal alterations of cardiac morphology. Finally, chlorpheniramine (0.15 or 0.45 mg/kg i.v.) did not prevent the onset of chronic cardiomyopathy induced by DXR in mouse. In conclusion, our results show that the role of histamine in the onset of DXR-induced chronic cardiomyopathy, at least in mouse, remains questionable and suggest that this animal, because of its high natural resistance to histamine, is not a suitable experimental model to investigate the cardiovascular pharmacology of drug-induced histamine release.

1. 1. We have investigated the kinetics of inhibition of cathepsin D in heart, liver and skeletal muscle of CD-1 mice following administration of 25, 50, 100 and 200 mg/kg i.p. of pepstatin A, a specific inhibitor of this protease. 2. 2. In the liver, a significant inhibition of cathepsin D occurred up to at least 15 days, whereas, in heart and skeletal muscle, this inhibition lasted for a much shorter period of time. 3. 3. These results show that the recovery of enzyme activity to normal values is dose-dependent and that, at the same dose level, marked differences occur in the recovery of enzyme activity in these organ tissues, the liver being the most sensitive one. © 1988.

Some clinical studies that were performed for the purpose of assessing the potential cardiotoxicity of mitoxantrone (DHAD) have shown that repeated administrations of the drugs in some patients cause a mild impairment of cardiac functions and morphological changes in the myocardial cells qualitatively similar to those elicited by anthracyclines. Since doxorubicin has been reported to cause acute cardiac effects, probably related to its chronic cardiotoxicity, experiments were carried out on the rabbit heart to investigate whether DHAD is also able to induce acute cardiac effects. Our results show that this drug caused a reversible dose-related impairment of cardiac contractility on the isolated and perfused rabbit heart while it was not able to induce ECG alterations in normal rabbits. These findings demonstrate that in the rabbit DHAD induces an acute cardiac activity qualitatively similar to that of doxorubicin and suggest that this animal model could be a useful tool to study the cardiac actions and related pathogenetic mechanism(s) of this antitumor drug.