Cathepsin D expression levels in nongynecological solid tumors: Clinical and therapeutic implications

Cathepsin D is a lysosomal acid proteinase which is involved in the malignant progression of breast cancer and other gynecological tumors. Clinical investigations have shown that in breast cancer patients cathepsin D overexpression was significantly correlated with a shorter free-time disease and overall survival, whereas in patients with ovarian or endometrial cancer this phenomenon was associated with tumor aggressiveness and a degree of chemoresistance to various antitumor drugs such as anthracyclines, cis-platinum and vinca alkaloids. Therefore, a lot of research has been undertaken to evaluate the role and the prognostic value of cathepsin D also in other solid neoplasms. However, conflicting results have been generated from these studies. The discrepancies in these results may, in part, be explained with the different methodological approaches used in order to determine the levels of expression of the enzyme in tumor tissues and body fluids. Further investigations using well-standardized techniques may better define the clinical significance of cathepsin D expression in solid tumors. Nevertheless, evidence emerging from these studies indicates that this proteinase seems to facilitate early phases of tumor progression such as cell proliferation and local dissemination. These findings support the concept that cathepsin D may be a useful marker for identifying patients with highly malignant tumor phenotypes who may need more aggressive clinical treatment; this enzyme may also be considered as a potential target for a novel therapeutic approach in the treatment of solid neoplasms

Vitamin D in cancer chemoprevention

Context: There is increasing evidence that Vitamin D (Vit D) and its metabolites, besides their well-known calcium-related functions, may also exert antiproliferative, pro-differentiating, and immune modulatory effects on tumor cells in vitro and may also delay tumor growth in vivo. Objective: The aim of this review is to provide fresh insight into the most recent advances on the role of Vit D and its analogues as chemopreventive drugs in cancer therapy. Methods: A systematic review of experimental and clinical studies on Vit D and cancer was undertaken by using the major electronic health database including ISI Web of Science, Medline, PubMed, Scopus and Google Scholar. Results and conclusion: Experimental and clinical observations suggest that Vit D and its analogues may be effective in preventing the malignant transformation and/or the progression of various types of human tumors including breast cancer, prostate cancer, colorectal cancer, and some hematological malignances. These findings suggest the possibility of the clinical use of these molecules as novel potential chemopreventive and anticancer agent

Effects of oleuropein on tumor cell growth and bone remodelling: Potential clinical implications for the prevention and treatment of malignant bone diseases.

Oleuropein (Ole) is the main bioactive phenolic compound present in olive leaves, fruits and olive oil. This molecule has been shown to exert beneficial effects on several human pathological conditions. In particular, recent preclinical and observational studies have provided evidence that Ole exhibits chemo-preventive effects on different types of human tumors. Studies undertaken to elucidate the specific mechanisms underlying these effects have shown that this molecule may thwart several key steps of malignant progression, including tumor cell proliferation, survival, angiogenesis, invasion and metastasis, by modulating the expression and activity of several growth factors, cytokines, adhesion molecules and enzymes involved in these processes. Interestingly, experimental observations have highlighted the fact that most of these signalling molecules also appear to be actively involved in the homing and growth of disseminating cancer cells in bones and, ultimately, in the development of metastatic bone diseases. These findings, and the experimental and clinical data reporting the preventive activity of Ole on various pathological conditions associated with a bone loss, are indicative of a potential therapeutic role of this molecule in the prevention and treatment of cancer-related bone diseases. This paper provides a current overview regarding the molecular mechanisms and the experimental findings underpinning a possible clinical role of Ole in the prevention and development of cancer-related bone diseases

Effects of amsacrine (m-AMSA) a new aminoacridine antitumor drug, on the rabbit heart

There is emerging clinical evidence that amsacrine (m-AMSA) administration may be associated with cardiotoxic effects such as severe, even fatal, ventricular arrhythmias and impairment of the inotropic performance of the heart. Information on the cardiac effects of m-AMSA in animals is scanty. Studies on mice, dogs, and monkeys have not evidenced the cardiotoxicity of the compound. The data presented in this paper show that m-AMSA causes acute ECG alterations in normal rabbits and a dose-related negative inotropic effect on the isolated rabbit heart, suggesting that this species may be a useful model for the study of the cardiac actions of this antiblastic

Serum follistatin in patients with prostate cancer metastatic to the bone

The clinical significance of circulating fol- listatin (FLST), an inhibitor of the multifunctional cytokine activin A (Act A), was investigated in patients with prostate cancer (PCa). The serum concentrations of this molecule were determined by an enzyme-linked immunosorbent assay (ELISA) in PCa patients with (M?) or without (M0) bone metastases, in patients with benign prostate hyperplasia (BPH) and in healthy sub- jects (HS). The effectiveness of FLST in detecting PCa patients with skeletal metastases was determined by the receiver operating characteristic (ROC) curve analysis. Serum FLST was significantly higher in PCa patients than in BPH patients (P = 0.001) or HS (P = 0.011). Conversely, in BPH patients, FLST levels resulted lower than in HS (P = 0.025). In cancer patients the serum concentrations of FLST significantly correlated with the presence of bone metastases (P = 0.0005) or increased PSA levels (P = 0.04). Interestingly, significant differ- ences in the ratio between FLST and Act A serum concentrations (FLST/Act A) were observed between HS and BPH patients (P = 0.001) or PCa patients (P = 0.0005). Finally, ROC curve analysis, highlighted a sound diagnostic performance of FLST in detecting patients (P = 0.0001). However, the diagnostic effectiveness of FLST did not result significantly supe- rior to that of Act A or PSA. These findings suggest that FLST may be regarded as a potential, molecular target in the treatment of metastatic bone disease while its clinical role as soluble marker in the clinical management of PCa patients with bone metastases needs to be better defined

Influence of quercetin and luteolin on the activity of the catalase: study ex vivo about erythrocytes in smokers and non-smokers

Flavonoids are a group of polyphenolic compounds with different chemical structure and properties. These compounds may scavenge free radical species and other oxidants. In previous studies, we have observed that some polyphenols are able to cross the erythrocyte\u2019smembrane and this process is influenced by the plasmatic albumin; in fact quercetin intracellular concentrations is albumin dose depending. The influence of flavonoids on catalase activity has been reported in some papers but the results are contradictory. Some authors have found an increase of catalase activity in cell in the presence of flavonoids. Others have observed any effect or even a decrease of catalase activity.The present work is based on a study of Krych\u2019s, in which the influence of flavonoids on catalase in model system has been evaluated. Aim of this work was to study the role of red body cells in the antioxidant balance. The primary goal was to evaluate the antioxidant status of no-smokers and ever-smokers healthy subjects by the determination of the plasma antioxidant capacity and of the catalase activity of erythrocyte and then to evaluate if flavonoids (quercetin and luteolin) are able to modify the enzyme activity. This is a pilot study. Nine healthy subjects, aged 24-55 years were recruited. None of the subjects had any pathologies at the time of sampling. We assayed the CAT activity in erythrocytes isolated from whole blood of the subjects by the colorimetric assay and the plasma antioxidant capacity using the spectrophotometric method known crocin bleaching assay. The catalase activity was performed in human erythrocytes (control) and after the incubation of them with the flavonoids (quercetin and luteolin). The flavonoids were efficiently taken up by human erythrocytes in dose-depending manner. There was no significant difference in the percent accumulation of both molecules (quercetin and luteolin) inside the erythrocytes when incubated at the same concentration of 50\u3bcM. In physiologic condition the catalase activity varies from 28.6 mU/g protein to 40.6 mU/g protein. Data have shown that CAT activity of erythrocytes was significantly lower in ever smokers than in nosmokers. It was also found that Quercetin at the concentration of 100\u3bcM is able to increase the catalase levels in ever-smokers up to the normal values observed in no smokers. The study on the luteolin has not produced the same effects. In fact, Luteolin is able to reduce the CAT levels in no-smokers subject according with the data from Krych. The different actions of compounds on catalase can been explained as consequence of flavonoid interaction with enzymatic protein. The inhibiting action of the luteolin can be a consequence of a conformational change which occurs upon the flavonoid binding to catalase. This interaction changes the geometry of the substrate channel and thus inhibits the reaction of H2O2 with the heme center. Plasma antioxidant capacity was lower in no smokers than in smokers. An inverse correlation has been found between age and plasma antioxidant capacity. From the results of this study affirms that an oxidative stress condition is present in ever-smokers respect to non-smokers, but the quercetin is able to restore the erythrocyte oxidative stress condition of ever-smokers back to the normality. Further studies are necessary in the future to better investigate the role of luteolin on the catalase activity of human erythrocytes