Zinc oxide pieces obtained by pressing and slip casting: physical, structural and photocatalytic properties.

Photocatalysis is a promising alternative for the decontamination of effluents. In this paper, immobilized ZnO-based photocatalysts were obtained by pressing and by slip casting. The cylindrical pieces were heat-treated at 800°C. The samples were characterized by the method based on the principle of Archimedes, XRD, FTIR, Raman, diffuse reflectance and SEM. The samples obtained by slip casting presented lower apparent density (3.12 ± 0.04 g/cm3), higher apparent porosity (44.87 ± 0.47%) and smaller grain size (0.48 ± 0.05 µm) when compared to the pressed samples, with mean apparent density of 5.37 ± 0.08 g/cm3, apparent porosity of 1.56 ± 0.10% and grain size of 0.64 ± 0.02 µm. The performances of the samples were attested by the photocatalytic degradation of Rhodamine B (RhB) under UV-C irradiation (maximum intensity at 254 nm). The samples obtained by slip casting showed photocatalytic degradation between 80% and 90%, while the pressed samples showed degradation between 40% and 60%. The reuse of the photocatalysts was evaluated over five cycles of photocatalytic degradation, in which there was no loss of performance of the samples obtained by slip casting; however, the pressed samples showed a loss of photocatalytic efficiency starting from the third-cycle. Photocatalytic assays were carried out with different dye concentrations, in which the slip casting samples showed better photocatalytic efficiency (degradation of 80% for a RhB concentration of 10 mg/L) due to higher porosity and surface area compared to pressed samples, and there was a loss of performance in higher concentrations.

Tyrosine phosphorylation of estradiol receptor by Src regulates its hormone-dependent nuclear export and cell cycle progression in breast cancer cells.

We report that in breast cancer cells, tyrosine phosphorylation of the estradiol receptor alpha (ERalpha) by Src regulates cytoplasmic localization of the receptor and DNA synthesis. Inhibition of Src or use of a peptide mimicking the ERalpha p-Tyr537 sequence abolishes ERalpha tyrosine phosphorylation and traps the receptor in nuclei of estradiol-treated MCF-7 cells. An ERalpha mutant carrying a mutation of Tyr537 to phenylalanine (ER537F) persistently localizes in nuclei of various cell types. In contrast with ERalpha wt, ER537F does not associate with Ran and its interaction with Crm1 is insensitive to estradiol. Thus, independently of estradiol, ER537F is retained in nuclei, where it entangles FKHR-driving cell cycle arrest. Chromatin immunoprecipitation analysis reveals that overexpression of ER537F in breast cancer cells enhances FKHR interaction with cyclin D1 promoter. This mutant also counteracts cell transformation by the activated forms of Src or PI3-K. In conclusion, in addition to regulating receptor localization, ERalpha phosphorylation by Src is required for hormone responsiveness of DNA synthesis in breast cancer cells.

Chronic anemia due to mitomycin C is drug dose-dependent, normocytic, progressive, related to erythropoietin levels and quantitatively predictable: implications for radiochemotherapy.

Mitomycin C (MC) is used as therapy against solid tumors, also combined with other chemotherapeutic agents or radiotherapy. It may cause acute, subacute, or chronic anemia capable of modifying the results of chemo- and radiotherapy. Erythropoietin may be lowered by cancer itself or because of chemoradiotherapy. There are few studies investigating the relationship between erythropoietin and chronic anemia.We prospectively analyzed the chronic anemia and erythropoietin in 38 patients with solid cancer. Patients were 40 to 82 years of age. MC was randomly given every 3 weeks as a single drug at 10 or 20 mg/m². When myelotoxicity occurred the next therapy cycle was delayed until recovery. RBC indices, hemolysis, erythropoietin, liver and kidney function were studied. MC cycles were 136 (3.6 ± 1.4 per pt), 32 being delayed because of myelotoxicity.Hematocrit, hemoglobin and RBC were inversely related to the cumulative dose (r = 0.70 to 0.86; p 0.03 to 0.01) of MC. Other tests remained stable. Anemia occurred almost twofold earlier in the 20 mg/m² group (p=0.049). basal erythropoietin, already lower than in age and sex watched 81 non cancerous subjects (p<0.001), decreased during MC therapy (p<0.01). For each given MC mg/m² a 0.0372 Hb mg/dl reduction occurred. Chronic anemia due to MC is accompanied by erythropoietin reduction. These results can help in designing chemoradiotherapy.

TPMT genotype and the use of thiopurines in paediatric inflammatory bowel disease.

BACKGROUND: Thiopurines are used in the treatment of inflammatory bowel disease. They are metabolised via methylation by thiopurine-S-methyltransferase (TPMT), which displays a genetically determined polymorphic activity. Subjects with reduced TPMT activity have a higher concentration of active thiopurine metabolites and may be at increased risk of bone-marrow suppression. AIMS: To evaluate the relevance of TPMT genotyping in the management of thiopurines therapy in inflammatory bowel disease patients. PATIENTS AND METHODS: Adverse effects and clinical response were determined retrospectively and correlated with TPMT genotype in 70 paediatric inflammatory bowel disease patients. RESULTS: Nineteen patients (27.1%) developed adverse effects; of the 51 who did not, 34 (66.7%) responded to treatment. Five patients (7.1%) were heterozygous for a variant TPMT allele; two of these (40%) were intolerant to thiopurines, compared to 17 of the 65 patients (26.2%) with a wild type gene (O.R. 1.88, 95% CI 0.29-12.2, p=0.61); among the 34 responders, the median dosage of the drug required to obtain remission was lower for mutated than for wild type patients (1.6mgkg(-1)day(-1) versus 2.0mgkg(-1)day(-1), p=0.043). CONCLUSIONS: There was no significant association between adverse effects of thiopurines and TPMT heterozygous genotype, but TPMT genotyping could be useful in establishing the most appropriate dose of thiopurines to start treatment.

Effects of melatonin on doxorubicin cytotoxicity in sensitive and pleiotropically resistant tumor cells.

Melatonin has been reported to attenuate the oxidative damage caused by doxorubicin on kidney, brain, heart and bone marrow, whereas the in vivo antitumor effects of doxorubicin were not attenuated. The effects of melatonin on doxorubicin cytotoxicity have, therefore, been examined on human normal mammary epithelium HBL-100, on mammary adenocarcinoma MCF-7, on colon carcinoma LoVo, and on mouse P388 leukemia cell lines, and on tumor cell sublines pleiotropically resistant to anthracyclines. Melatonin in the concentration range 10-2000 pg/mL causes an inhibition of the growth of the human cell lines examined which is not clearly dose-dependent and less than 25% when significant. Melatonin similarly causes minor effects on doxorubicin cytotoxicity either on the parental human cell lines or on their resistant sublines. On the contrary, 200-1000 pg/mL melatonin cause a significant and dose-dependent partial sensitization to doxorubicin of resistant P388 mouse leukemia (P388/ADR), which occurs also in vivo, as indicated by a significant increase in survival time of the hosts. Doxorubicin intracellular concentrations in P388/ADR cells are increased by melatonin, suggesting that melatonin might inhibit P-glycoprotein-mediated doxorubicin efflux from the cells. These results indicate that the use of melatonin in clinical cancer treatment should not pose the risk of an attenuation of the effectiveness of doxorubicin, and encourage the further examination of the possible reduction by melatonin of the host toxicity of antitumor chemotherapy.

Expression and function of P-glycoprotein and absence of multidrug resistance-related protein in rat and beige mouse peritoneal mast cells.

To clarify the function of the multidrug transporter P-glycoprotein in mast cells we used the green fluorescent compound Bodipy-FL-verapamil, which is a substrate of P-glycoprotein. This compound is also transported by Multidrug Resistance-related Protein (MRP), another membrane transport protein expressed in many tumour resistant cells as well as in normal cells. When rat peritoneal mast cells were incubated with Bodipy-verapamil, a rapid uptake of this compound was observed. Pretreatment with modulators of P-glycoprotein activity, such as verapamil and vinblastine, increased Bodipy-verapamil intracellular concentrations. In addition, Bodipy-verapamil efflux from these cells was rapid and also inhibited by verapamil and vinblastine. In contrast, no effect was observed when cells were treated with agents, such as probenecid and indomethacin, that are known inhibitors of MRP. Methylamine and monensin, substances that modify the pH values in the granules, were able to lower the concentrations of Bodipy-verapamil. Microscopical observations, conducted in both rat and beige mouse mast cells, demonstrated that the fluorochrome accumulated in the cytoplasmic secretory granules. RT-PCR performed on rat peritoneal mast cells revealed the presence of MDR1a and MDR1b mRNAs; on the contrary, MRP mRNA was not expressed. Mast cells were further treated with the fluorescent probe LysoSensor Blue, a weak base that becomes fluorescent when inside acidic organelles. This substance accumulated in mast cell granular structures and its fluorescence was reduced either by treatment with P-glycoprotein modulators or with agents that disrupt pH gradients. In conclusion, these data further confirm the presence of an active P-glycoprotein, but not of MRP, in rat peritoneal mast cells. These findings, coupled with previous ultrastructural data, lend further support to the assumption that this protein is located on the mast cell perigranular membrane. The functional role of P-glycoprotein in these cells is at present unclear, but a possible involvement in the transport of molecules from the granules to the cytosol can be hypothesized. Alternatively, this protein might be indirectly implicated in changes of pH values inside secretory granules.

Characterization of multidrug transporters in a normal renal tubular cell line resistant to doxorubicin. Multidrug transporters in the LLC-PK(1) cell line and its resistant counterpart.

LLC-PK(1) is a proximal tubular cell line derived from normal pig kidney which has a structure and function similar to those of renal proximal tubular cells and which expresses baseline levels of P-glycoprotein. We isolated by drug selection a doxorubicin-resistant cell line (LLC-PK(1)/ADR) that exhibited a multidrug-resistant phenotype; this cell line was characterized by reduced intracellular drug concentrations, an increased drug extrusion, and increased expression of a 170-kDa P-glycoprotein detected by Western blot analysis with monoclonal antibody C219. In addition, an increased expression of MDR1 mRNA was seen by reverse transcriptase-polymerase chain reaction. These results suggest that it is possible to induce the overexpression of P-glycoprotein by chronic treatment with doxorubicin in a normal cell line that physiologically expresses low levels of this protein. This multi-resistant cell line could provide an interesting model for studying the role of P-glycoprotein and the consequence of its induction in a normal tissue.

Cytofluorimetric analysis of a renal tubular cell line and its resistant counterpart.

P-glycoprotein (P-gp) and multidrug resistance related protein (MRP) overexpression is often responsible of the development of multidrug resistance in cancer therapy. These proteins are also expressed in normal tissues, where their physiological role is related to the extrusion of endogenous toxins or to secretory function in liver and kidney. The LLC-PK1 cell line is derived from normal pig proximal renal tubule and physiologically expresses low levels of P-gp and MRP. A resistant cell line (LLC-PK1/ADR) has been established in our laboratory by chronic exposure to increasing doses of doxorubicin. Cytofluorimetric analysis of P-gp and MRP expression performed by C219 and MRPm6 immunofluorescence detection showed that these cells overexpress P-gp but not MRP. The uptake of doxorubicin and rhodamine 123 has been quantified in LLC-PK1 and LLC-PK1/ADR cells and compared with data obtained using other tumor cell lines commonly used as reference for studying P-gp or MRP overexpression. P388 sensitive cells and its resistant counterpart P388/ADR cells, which overexpress P-gp and PANC-1 cells, which express high levels of MRP were used. A lower fluorescence intensity was evident with both doxorubicin and rhodamine 123 in LLC-PK1/ADR as well as in P388/ADR cells, that overexpresses P-gp, in comparison with the parental lines. The uptake was increased by a pretreatment with verapamil. Verapamil was completely ineffective on PANC-1 cells, confirming a selective effect of this inhibitor on P-gp. Propidium iodide staining, performed after doxorubicin treatment, confirmed a higher cytotoxicity of the antineoplastic drug in the LLC-PK1 cells compared with the resistant counterpart.

Physicians' attitudes to and problems with truth-telling to cancer patients.

Disclosure of a diagnosis of cancer to patients is a major problem among physicians in Italy. The aim of the study was to assess physicians' attitudes to and opinions about disclosure. A convenience sample of 675 physicians in Udine (North Italy) completed a ten-item questionnaire. About 45% indicated that, in principle, patients should always be informed of the diagnosis, but only 25% reported that they always disclosed the diagnosis in practice. Physicians with a surgical specialization employed in general hospitals endorsed disclosure of the diagnosis more frequently than GPs and older physicians. One third of the responding physicians persist in the belief that the patients never want to know the truth. Hospital doctors considered the hospital, rather than the patient's home, was the most appropriate place to inform the patients. The opposite result was found among GPs. Almost all the physicians endorsed the involvement of family members when disclosing the diagnosis, but, at the same time they also indicated that families usually prefer their ill relative not to be informed. Ninety-five per cent of physicians believed that the GP should always be involved in the processes of diagnosis and communication, and 48% indicated that the GP should communicate the diagnosis to the patient (as opposed to the physician who made the diagnosis). Having guidelines for breaking bad news to patients was indicated as an important need by 86% of the responding physicians. Despite changes in medical education, improvement of communication skills in dealing with cancer patients and their families represents an important need in healthcare settings.

Biochemical and microscopic evidence for the internalization of drug-containing mast cell granules by macrophages and smooth muscle cells.

During mast cell degranulation the soluble component of the granule is released into extracellular fluid, whereas two neutral proteases and heparin proteoglycans form the extracellular granule remnants. These structures are negatively charged and bind with high affinity LDL and other basic molecules. In this study we show that granule remnants expelled into extracellular fluid are able to bind the aminoglycoside antibiotic gentamicin and the anticancer agent doxorubicin in a dose-dependent manner. In addition, granule remnants loaded with the two basic substances are subsequently phagocytosed by macrophages. Indeed, when cells are incubated for 24 h with 1 mg/ml gentamicin, the intracellular concentration of the drug, which in basal conditions is extremely low, increases significantly in the presence of degranulating mast cells (from 5.1 +/- 1.0 to 25.4 +/- 2.5 microg/mg protein) and a good correlation between histamine release and gentamicin uptake is evident. The antineoplastic agent doxorubicin can penetrate cells by passive diffusion; however, when mast cells are added to macrophage monolayer, incubated for 30 min with 50 microM of the antineoplastic agent, a significant increase in intracellular doxorubicin concentration is observed (from 3.5 +/- 0.2 to 4.7 +/- 0.2 microg/mg protein). Internalization of granule remnants carrying gentamicin or doxorubicin is also evident in smooth muscle cells of the synthetic phenotype. In particular, when smooth muscle cells are incubated for 24 h with 1 mg/ml gentamicin, addition of isolated granules increases the uptake from 2.4 +/- 0.2 to 4.8 +/- 0.4 microg/mg protein. Similar results are obtained in smooth muscle cells incubated for 4 h with doxorubicin 50 microM (from 3.3 +/- 0.2 to 4.8 +/- 0.5 microg/mg protein). Data are confirmed by microscopic experiments by means of fluorescence microscopy and electron microscopic studies. The study demonstrates that basic substances can enter phagocytic cells when loaded to granule remnants. The phenomenon can be of particular interest for substances like the aminoglycosides that do not cross biological membranes; indeed, the storage of these antibiotics in phagocytic cells could have important consequences on their antibacterial activity in vivo. Macrophages and smooth muscle cells can also act as a reservoir for doxorubicin. High concentrations of the antineoplastic agent in these cells could be responsible for toxicity, as well as play an important role in the transport of the drug to tumor cells.

Stress and chemotherapy. Combined effects on tumor progression and immunity in animal models.

In mice bearing Lewis lung carcinoma, rotational and restraint stress specifically increases the formation of lung metastasis, and restraint stress markedly attenuates the antitumor effects of cyclophosphamide. The aim of this investigation was therefore to examine the effects of restraint stress on tumor metastasis in mice bearing MCa mammary carcinoma, and on the effectiveness of CCNU and DTIC. Restraint stress increases MCa mammary carcinoma metastasis, causes a marked reduction in cyclophosphamide activity, and a minor attenuation of the effects of CCNU and DTIC. The possible occurrence of seasonal factors, observed for the increase by rotational stress of Lewis lung carcinoma metastasis, was also determined for cyclophosphamide effectiveness. The survival time of control mice is longer in February than in June, and is not appreciably modified by rotational stress. The effects of cyclophosphamide are similar in both seasonal periods, and are similarly attenuated by rotational stress. The seasonal effects of rotational stress, and the reduction of the effects of cyclophosphamide caused by rotational stress, are accompanied by corresponding variations in the number of CD3+ and CD4+ splenic T-lymphocyte subsets and in the CD4+/CD8+ ratio, respectively. The reported effects of stress on tumor progression and on the effectiveness of cyclophosphamide thus appear to occur via modulation of immune responses of the host directed against the tumor. These data appear of interest for their experimental implications, and suggest the opportunity to consider the role that the stress during treatment may play in determining the effectiveness of clinical antitumor chemotherapy.

Melatonin administration in tumor-bearing mice (intact and pinealectomized) in relation to stress, zinc, thymulin and IL-2.

Melatonin (MEL) may counteract tumors through a direct oncostatic role. MEL is also an antistress agent with immunoenhancing properties against tumors due to a suppressive role of MEL on corticosterone release. Rotational stress (RS) (spatial disorientation) facilitates metastasis progression in mice. Also, MEL counteracts tumors because of its influence on immune responses via the metabolic zinc pool, which, is reduced in tumors and stress. Zinc is required for normal thymic endocrine activity (i.e. thymulin) and interleukin-2 (IL-2) production. Because in vivo data is still controversial, exogenous MEL treatment (22 days in drinking water) in both intact and pinealectomized (px) mice bearing Lewis lung carcinoma leads to significant decrements of metastasis volume, restoration of the negative crude zinc balance, recovery of thymulin activity and increment of IL-2 exclusively in intact and px tumor bearing mice subjected to RS. Significant inverse correlations are found in both stressed intact and px tumor bearing mice after MEL treatment between zinc and corticosterone (r = 0.78, P < 0.01; r = 0.80, P < 0.01, respectively). Positive correlations between zinc and IL-2 (r = 0.75, P < 0.01; r = 0.73, P < 0.01, respectively) or thymulin (r = 0.75, P < 0.01; r = 0.82, P < 0.01, respectively) are observed in same models of mice. These findings suggest a MEL action to decrease metastasis mediated by a possible interplay between zinc and MEL, via corticosterone, with consequent restoration of thymic efficiency and IL-2 production. MEL as an antistress agent with immunoenhancing properties in cancer deserves further consideration.nuclear factor-kb; POMC, proopiomelanocortin; Px, pinealectomized mice; RIA, radioimmunoassay; RS, rotational stress; SDI, stressed intact mice; SDPx, stressed pinealectomized mice; TNF-alpha, tumor necrosis factor-alpha; ZnFTS, active zinc-bound thymulin; ZnFTS + FTS, total thymulin.

Melatonin and oxidative damage in mice liver induced by the prooxidant antitumor drug, adriamycin.

Antioxidant properties have been attributed to melatonin; it seemed therefore worthwhile to determine its effects in relation to the prooxidant action of adriamycin, which contributes to its toxic and therapeutic effects. Melatonin effectively acts as a direct free radical scavenger in the concentration range of 20-100 microM as determined in vitro, using Fenton reaction as a source of free radicals that were determined by EPR using spin trapping method. Following the administration of a single i.v. dose of 28 mg/Kg or of 3 repeated i. p. doses of 5 mg/Kg adriamycin to CBA mice, glutathione levels in the liver cells were significantly reduced. When the treatment with adriamycin was preceded by the s.c. administration of 2 mg/Kg melatonin, the decrease in total and reduced glutathione concentrations was significantly prevented. A significant increase in lipid peroxidation was observed in liver cells after a single administration of adriamycin which was not attenuated by pretreatment with melatonin. These results indicate that further examination of the possible protective action of melatonin on the toxic effects of prooxidant antitumor drugs on normal and neoplastic tissues would be of interest also in relation to their chronotoxicological properties.

Melatonin decreases bone marrow and lymphatic toxicity of adriamycin in mice bearing TLX5 lymphoma.

When CBA male mice bearing TLX5 lymphoma were treated in the evening with a single i.v. dose of adriamycin (20-40 mg/Kg), the administration of a single pharmacological dose of melatonin (10 mg/kg s.c.) 1 hr earlier reduced the acute mortality from 10/24 to 2/24. The increase in survival time caused by adriamycin over drug untreated controls was not reduced by melatonin. The administration of melatonin alone did not cause any antitumor or evident toxic effect. Melatonin also attenuated the reduction caused by adriamycin in the number of bone marrow GM-CFU, and of CD3+, CD4+ and CD8+ splenic T-lymphocyte subsets. Reduced and total glutathione levels were decreased in the bone marrow and in the liver cells of the animals treated with adriamycin, and were significantly restored by melatonin. Moreover, lipid peroxidation by adriamycin was reduced by melatonin, as indicated by malondialdehyde measurement in the liver of the treated animals. These data indicate that the protective effects of melatonin against the host toxicity of the prooxidant antitumor drug, adriamycin, might be attributed at least partially to its antioxidant properties. These findings appear of interest in relation to the physiological rhythmic levels of endogenous melatonin and to the chronotoxicology of anthracyclines.

Seasonal effects of rotational stress on Lewis lung carcinoma metastasis and T-lymphocyte subsets in mice.

Rotational stress specifically increases the formation of spontaneous lung metastasis in mice bearing Lewis lung carcinoma, without significantly modifying the growth of primary tumor. The increase in metastasis number and volume caused by rotational stress varies in magnitude with a highly significant circannual rhythm; the acrophase approximately coincides with summer solstice. Rotational stress causes a significant reduction in the number of CD3+ and CD4+ T-lymphocyte subsets in summer, whereas in winter the number of CD3+ subset is significantly increased; the CD4+/CD8+ ratio and the number of NK 1.1 antigen positive cells are not significantly modified by rotational stress in both periods considered. The increase in metastasis formation by rotational stress thus appears to negatively correlate with the number of splenic CD3+ and CD4+ T-lymphocyte subsets. This seasonal behavior occurs in spite of the control of light cycle, temperature and humidity in the animal housing, suggesting the existence in the host of an endogenous oscillator with a circannual period. These data indicate the opportunity to consider endogenous rhythms within the host, as well as seasonal factors, in studies on stress and neuroimmunomodulation in experimental oncology.

Restraint stress reduces the antitumor efficacy of cyclophosphamide in tumor-bearing mice.

Treatment with the cytotoxic antitumor drug cyclophosphamide is highly effective in mice bearing Lewis lung carcinoma, causing the absence of macroscopically detectable tumors at necroscopy after sacrifice. When the effects of the treatment on survival are determined, a significant increase in survival time and in the proportion of long-term survivors is observed. When restraint stress is further applied, tumors develop in all of the mice treated with cyclophosphamide, and survival time and the fraction of long-term survivors are significantly reduced. Flow cytometry of splenic T-lymphocyte subsets in normal mice indicates a significant decrease in the number of CD3+, CD4+, and CD8+ subsets after treatment with cyclophosphamide and after application of restraint stress; the interaction of the two treatments is significant for CD3+ and marginally significant for CD4+ subsets. The attenuation by restraint stress which was observed for the effects of cyclophosphamide on the presence of tumors at necroscopy and for the survival of the treated mice might thus be interpreted as follows: restraint stress attenuates the immune functions of the host directed toward the weakly immunogenic tumor, an effect which, in the absence of restraint stress, interacts effectively with the cytotoxic action of cyclophosphamide toward tumor cells. The results obtained using this animal model thus indicate that experimental stress reduces the therapeutic efficacy of a cytotoxic antitumor drug; experimental and clinical implications are discussed.

Suppression of metastatic potential and up-regulation of gelatinases and uPA in LLC by protracted in vivo treatment with dacarbazine or razoxane.

Treatment of mouse Lewis lung carcinoma with razoxane or dacarbazine was protracted for 10 transplant generations. While the capacity of the treated tumors to grow locally in immuno-competent or in immuno-depressed hosts was retained and not significantly modified, the metastatic phenotype was eliminated when the treated tumor cells were transplanted into immuno-competent hosts. The reduction in metastatic potential was slightly less pronounced, in terms of both number and volume of metastases, when the treated tumor cells were transplanted into immuno-depressed hosts. These properties were retained after 3 transplant generations without treatment. Northern blotting and zymography of primary-tumor crude extracts revealed that treatment with either razoxane or dacarbazine for one generation approximately doubled the expression of MMP-2 and MMP-9, while lacking any effect on that of 1.0 and of 3.5 kb TIMP-2. When the treatment was maintained for 10 generations, the expression of MMP-2 and MMP-9 for both drugs showed up-regulation of approximately 10- and 2-fold respectively. TIMP-2 mRNA of 1.0 kb doubled its expression, while that of 3.5 kb registered just above the control. Dacarbazine doubled the expression of uPA after 10 generations, while razoxane boosted it approximately 3-fold after either 1 or 10 generations. The permanent loss of metastatic phenotype induced in Lewis lung carcinoma by dacarbazine and razoxane is thus attributable to biological mechanisms independent of down-regulation of expression and/or activation of the 2 gelatinases.

Psychosocial factors and breast cancer: a 6-year Italian follow-up study.

BACKGROUND: Over the last 20 years contradictory results have been obtained as regards to the role of psychosocial factors in favouring the onset of breast cancer and/or in influencing disease progression. METHODS: The present study prospectively investigated the association between psychosocial variables and breast cancer in 95 out-patients. Within 3 months from the diagnosis the patients completed a series of questionnaires to evaluate psychological disturbances, emotional repression, adjustment to cancer, social support and occurrence of life events in the past. At a distance of 6 years from the first assessment, the patients' charts were re-examined in order to evaluate the course of cancer. RESULTS: A higher volume of primary tumour at surgery was shown in patients who had had stressful events in the 6 months preceding cancer diagnosis. At follow-up, no relationship was found between psychosocial variables and the course of disease. The analysis of the frequency of relapses and deaths, and the survival analysis indicated that positivity of loco-regional lymph nodes, infiltrating histotype of the tumour and tumour stage were the only significant predictors of the time of death. CONCLUSIONS: The study suggests that clinical and biological rather than psychosocial factors exert a major role in breast cancer progression.

Survival time in mice bearing TLX5 lymphoma subjected to rotational stress and chemotherapy with CCNU.

The effects of a psychological stress model rotational stress were examined in mice bearing TLX5 lymphoma. The survival time of the animals was determined as a function of tumor inoculum size and treatment with the antitumor drug, CCNU. Rotational stress significantly decreased the mean survival time of mice implanted with 10 or 10(2) tumor cells, and significantly increased tumor takes in mice implanted with 10 cells. Treatment with CCNU significantly prolonged the survival time of the treated animals; the application of rotational stress significantly attenuated the increase in survival time caused by CCNU. These results indicate that in mice with a limited tumor burden, psychological stress favors the progression of TLX5 lymphoma, and reduces the effectiveness of the antitumor drug, CCNU. Moreover, the experimental model employed may provide a tool useful for investigating the mechanisms involved in the sensitivity of lymphoma to psychosocial stress.

Blockers of adrenergic neurons and receptors, tumor progression and effects of rotational stress in mice.

The aim of this work was to determine the possible participation of adrenergic responses to the increase in tumor dissemination induced by rotational stress using drugs affecting monoaminergic function. The growth of the primary tumor and the formation of lung metastasis were determined in mice implanted with Lewis lung carcinoma, subjected to rotational stress and treated with the adrenergic neuron blocker reserpine, the alpha-receptor blocker phenoxybenzamine, and the beta-blocker propranolol. Treatment with reserpine markedly reduced the formation of spontaneous lung metastasis and completely abolished the increase in metastases caused by rotational stress without direct effect on tumor cells or blood vessels. Phenoxybenzamine and propranolol caused opposite effects on tumor progression. Previous immunosuppression by cyclophosphamide in mice with tumors reduced the antimetastatic effects of reserpine. These results suggesting the importance of the adrenergic modulation of immune resistance factors in controlling metastasis development and indicate a possible role in monitoring the use and effects of monoaminergic drugs in cancer patients.