Polyprenoic acid in hepatocellular carcinoma.
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Biomedical subjects
Publications and source records attributed to A Decensi.
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Bladder-washing-derived lymphocytes (BWDL) from 67 patients with bladder cancer were studied. The large majority of samples contained a pure population of T lymphocytes, whereas B and NK cells were absent. A comparative analysis of bladder lymphocytes and peripheral blood lymphocytes (PBL), collected in parallel, showed that BWDL significantly differed from PBL. In vitro cultures of bladder lymphocytes were attempted on 21 samples but in vitro expansion was only possible on six patients treated with bacillus Calmette-Guérin (BCG). This finding indicates that BWDL are characterized by a severe proliferative defect. Nevertheless, the addition of BCG on bladder lymphocytes expanded in vitro enhanced their proliferation, suggesting that this population is sensitized against BCG antigen(s). The analysis of T cell receptor restriction patterns showed that bladder lymphocytes from patients under BCG treatment were oligoclonal. A possible explanation for the efficiency of the immune response and good clinical outcome in patients treated with BCG could be found in the high homology between some BCG antigens and human heat-shock proteins, which are overexpressed in transformed cells.
PURPOSE: An increase in the incidence of endometrial cancer and a potential increase in related mortality has been associated with the administration of 20 mg tamoxifen, the dose adopted in breast cancer chemoprevention trials, thus urging studies on intermediate markers of risk. PATIENTS AND METHODS: Thirty-three women who received 20 mg tamoxifen as adjuvant breast cancer treatment underwent endometrial biopsy. Samples were divided for histologic examination, including a quantitative analysis of stromal:epithelial ratio, and an assessment of DNA ploidy and proliferation by flow cytometry. Results were compared with 37 symptomatic subjects. RESULTS: All histograms were DNA diploid. Compared with controls, a significant increase in the risk of proliferation as measured by the hyperdiploid fraction was associated with tamoxifen duration (< or = 36 months: cumulative odds ratio = 16.5, 95% confidence interval, 1.85 to 146.5; > 36 months: cumulative odds ratio = 28.2, 95% confidence interval, 2.56 to 310.6, P for trend < .05). Tamoxifen-induced risk was significantly reduced by the extent of menopausal status. No cases of cancer or epithelial hyperplasia were observed in the tamoxifen group, whereas seven cases of epithelial hyperplasia without atypia were observed in the control group. The effect of tamoxifen on proliferation was associated with an increase in the stromal component. CONCLUSION: Tamoxifen at 20 mg/d exerts a time-dependent proliferative effect on the endometrium, particularly in premenopausal and early postmenopausal women. This effect appears to be mediated by the stromal component, which accounts for the discrepancy between flow cytometry and histology. Our study provides preliminary evidence that the DNA flow cytometric hyperdiploid fraction may be a useful tool for monitoring endometrial cell proliferation in women exposed to tamoxifen.
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Retinoids exert various important biological effects in the control of normal growth, differentiation, and fetal development. While retinoic acid (RA) has entered clinical trials as a differentiation-promoting agent, it is only recently that the synthetic retinoid N-(4-hydroxyphenyl)retinamide (HPR) has been shown to be of potential clinical interest in cancer chemoprevention and treatment. Since thus far no data exist on the effects of HPR on neural crest cell-derived tumors, we have examined its in vitro effects on neuroblastoma (NB) cell lines and found that at relevant pharmacological concentrations it induces a dose-dependent growth inhibition. The antiproliferative effects of HPR were, in six of six cell lines tested, drastically more potent that those induced by an equimolar dose of RA. Time course growth analysis showed that HPR at 3 x 10(-6) M induces a very rapid (24-72 h) fall in thymidine uptake (> 90%), whereas at 3 x 10(-7) M it exhibits cytostatic effects. In contrast to RA, HPR did not show morphological changes typical of NB cell maturation nor did it induce the expression of any cytoskeletal protein associated with neuronal differentiation. DNA flow cytofluorimetric analysis revealed that HPR did not induce an arrest in a specific phase of the cell cycle while triggering apoptosis. This phenomenon was evidenced both by the visualization of "DNA ladders" on gel electrophoresis and by a quantitative assay for evaluating programmed cell death based upon the labeling of DNA breaks with tritiated thymidine. With the latter method, apoptotic cells were detectable as early as 3-6 h after treatment of NB cells with 10(-5) M HPR, while more than 50% of cells were apoptotic by 24-72 h following exposure to 3 x 10(-6) M HPR. In contrast, RA induced a low rate of apoptosis in NB cells only after 3-5 days. Time lapse photomicroscopy showed that NB cells treated with HPR underwent a death process highly reminiscent of apoptosis, with progressive condensation of the cytoplasm around the nucleus and intense cell shrinkage. The cells then rounded up and detached from the plate. Furthermore, propidium iodide staining of the DNA showed that a high proportion of cells treated with HPR displayed a small and brightly staining nucleus; chromatin appeared aggregated into dense masses in the nuclear periphery, a typical feature of apoptotic cells. In conclusion, our study demonstrates that contrary to the differentiation-promoting activity of RA, HPR dramatically suppresses NB cell growth by inducing programmed cell death.(ABSTRACT TRUNCATED AT 400 WORDS)
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Fenretinide or N-(4-hydroxyphenyl)retinamide is a vitamin A analogue synthesized in the United States in the late 1960s. This retinoid shows a preferential accumulation in breast instead of liver, is effective in the inhibition of chemically induced mammary carcinoma in rats, and has proved to be less toxic than many other vitamin A analogues. The Milan Cancer Institute has put a particular effort in this molecule in both the experimental and clinical fields. We have demonstrated, in animals and humans, that fenretinide induces a rapid reduction of retinol plasma concentration, that its blood levels remain constant during administration for as long as 5 years, and that the drug is able to accumulate in the human breast. To date, 2969 stage I breast cancer patients have been randomized to evaluate the efficacy of this retinoid to prevent contralateral new primaries, 709 subjects have been accrued in a prevention trial of basal cell carcinoma of the head and neck, and 153 patients entered a study the preliminary results of which already show the capability of fenretinide to prevent recurrences and new localizations of oral leukoplakia. Further studies on fenretinide will be aimed at evaluating its preventive efficacy in superficial bladder and prostate cancers and at exploring possible synergism with tamoxifen and interferons in breast cancer and skin cancer, respectively.
BACKGROUND: Fenretinide, a synthetic derivative of retinoic acid, is under study in clinical trials for the prevention of breast, skin basal cell, bladder, and oral cancer in patients at risk. Although fenretinide is well tolerated even after prolonged use, it does lower plasma retinol levels and thus may affect night vision. PURPOSE: The purpose of this study was to measure changes in dark adaptation resulting from fenretinide administration, to compare the measured results with the patient's subjective perception, to define the association with plasma retinol levels, to assess the reversibility of alterations in night vision, and to assess the effects of fenretinide on the surface of the eye. METHODS: The study involved 65 women who had been operated on for stage I breast cancer. Of the study group, 34 received 200 mg daily of fenretinide for a median of 32 months, while 31 control subjects did not. Dark adaptation was studied with the Goldmann-Weekers adaptometer and with a subjective questionnaire. Plasma retinol levels were measured at each test of dark adaptation. Effects of fenretinide on the ocular surface were evaluated through conjunctival impression cytology. RESULTS: Of the patients on fenretinide, eight (23.5%) showed mild and nine (26.5%) showed moderate alterations of measured dark adaptability, compared with just two controls (6.5%) with mild alterations (cumulative odds ratio = 15.4; P = .0008). A significant inverse correlation exists between the final sensitivity threshold of dark-adaptometry and plasma retinol levels, with mild alterations arising below 16 micrograms/dL and moderate alterations below 10 micrograms/dL. Abnormal rod function improved significantly after 7 days and normalized 1 month after use of fenretinide was stopped or vitamin A supplementation was begun, while the conventional 3-day drug suspension, or drug half dose, did not allow sufficient recovery. Alterations of conjunctival cytology were slightly higher in patients receiving fenretinide, but no clinical disorders of the ocular surface were observed. CONCLUSIONS: The women treated with 200 mg fenretinide daily showed a relatively high incidence of mild-to-moderate alterations of dark-adaptometry as measured with the Goldmann-Weekers adaptometer. However, the real-life implication of the measurements is an open question, for the questionnaire shows that 50% of the patients with altered dark adaptometry were asymptomatic.
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The nonsteroidal androgen-receptor antagonist nilutamide has previously been shown to inhibit adrenal androgen steroidogenesis in patients with prostatic carcinoma treated in combination with an LHRH agonist. In order to understand better the mechanisms subserving this observation, we have studied the effects of nilutamide alone on the serum concentrations of androstenedione (A), dehydroepiandrosterone (DHEA), and DHEA-sulphate (DHEA-S) in 12 patients with prostatic cancer and compared them with those achieved in 21 patients treated with the agonist D-Trp-6-LHRH. In addition, the adrenocorticotropic hormone (ACTH)-stimulated adrenal response and the thyrotropin releasing hormone (TRH)-stimulated prolactin (PRL) response observed in the patients treated with nilutamide were compared with a control group of healthy age-matched controls. No significant variation in the basal concentrations of adrenal androgens occurred either within or between both treatment groups. In response to ACTH, a decreased 17-alpha hydroxyprogesterone (17-OHP) accumulation and an augmented A/17-OHP ratio were observed in the antiandrogen group (P < 0.05 for both), suggesting the partial removal of the 17,20 lyase block which was distinctive of the untreated controls, while no significant difference was found for other steroids. Basal PRL levels were not affected by the antiandrogen, but the response to TRH was increased. We conclude that no significant inhibition of adrenal androgen secretion occurs after nilutamide or LHRH agonist treatment. Rather, administration of the antiandrogen alone may partially remove the physiological decrease in adrenal androgen secretion observed in the elderly.
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The effects of steroid hormones are pleiotropic. Similarly, non-steroidal oestrogen receptor antagonists such as tamoxifen exert partial agonistic effects with a species- and tissue-specific pattern. Conversely, little is known of the biological effects of non-steroidal anti-androgens, whose role has been investigated in the palliative treatment of prostate cancer. We studied the effects of the non-steroidal anti-androgen nilutamide on parameters of red blood cells, an androgen-dependent cell compartment, in 24 men with prostate cancer and compared the results with those obtained in 38 historical control patients treated with D-tryptophan-6-LHRH. Administration of the anti-androgen induced a limited rise in testosterone concentrations (from 14.1 +/- 1.8 up to a maximum of 19.6 +/- 2.3 nmol l-1) and a significant increase with time in haemoglobin and haematocrit (y = 12.6 g dl-1 + 0.15 months and y = 37.3% + 0.46 months respectively, P = 0.008 for both), while no change occurred in red blood cell count (y = 4.19 x 10(6) mm-3 + 0.02 months, P = 0.2). Conversely, no variation in erythroid parameters was observed in the patients treated with the LHRH analogue (haemoglobin = 12.7 + 0.02 months, P = 0.59; haematocrit = 38.1 + 0.02 months, P = 0.9; red blood cells = 4.34 x 10(6) mm-3 + 0.15 months, P = 0.4). The difference between the linear regression slopes of haemoglobin in the two treatment groups was significant (F-ratio = 3.39, P = 0.03). While the stimulation of erythropoiesis induced by the anti-androgen might be due to incomplete neutralisation of endogenous androgens at the bone marrow level, a cell-specific agonistic effect of the drug cannot be excluded, thus calling into question the designation of pure antagonists which has been attributed to this class of compounds. Ongoing randomised trials should address this issue.
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PURPOSE: Interferons have shown a definite activity in the intravesical treatment of residual papillary bladder cancer or carcinoma in situ (CIS). The purpose of the present study was to investigate the efficacy of interferon alfa-2b (IFN) as prophylactic treatment of superficial bladder cancer. PATIENTS AND METHODS: Two hundred eighty-seven patients with primary pTa G2, pT1 G1 to G2 superficial bladder cancer, following complete transurethral resection (TUR), were randomly allocated to receive intravesical treatment, either with IFN (50 x 10(6) IU) or mitomycin (MIT-C; 40 mg). Drugs were instilled on a weekly basis for a total of 8 weeks. RESULTS: MIT-C was superior to IFN treatment with respect to time to recurrence, relative recurrence rate, recurrence rate per 100 patients per month, and recurrence tumor rate per 100 patients per month. This difference was particularly evident in patients with pTa G2 tumors. After multivariate analysis, the number of primary tumors and tumor grade were the best predictors of recurrence, while allocated treatment had only a moderate effect. Intravesical treatment was well tolerated in both arms. However, more local toxicity was experienced by patients treated with MIT-C. On the other hand, fever occurred significantly more frequently in patients treated with IFN. CONCLUSION: IFN was less effective, although locally better tolerated, than MIT-C as prophylactic treatment of primary superficial bladder cancer.
Administration of the synthetic retinoid Fenretinide lowers circulating retinol and may thus affect night vision. We have recently shown that plasma retinol levels below 100 ng/ml are associated with moderate alterations of the dark adaptometry test. To identify which patients are more likely to experience a decrease of plasma retinol under this threshold, we measured plasma levels of retinol, Fenretinide, and its metabolite 4-MPR in a cohort of 28 women receiving Fenretinide at the daily dose of 200 mg and studied their relationship with clinical characteristics such as age, menstrual status, body mass index, and time on treatment. Our results show that patients aged over 55 years with a higher percentage of adipose tissue had higher plasma concentrations of 4-MPR, which turned out to be the major determinant of the retinol decrease. This subgroup may thus deserve careful ophthalmological surveillance.
We studied the effect of fenretinide [N-(4-hydroxyphenyl)retinamide (4-HPR)], a synthetic analogue of retinoic acid, on plasma insulin-like growth factor I (IGF-I) levels in a consecutive cohort of stage I breast cancer patients belonging to a randomized phase III trial of breast cancer chemoprevention. Thirty-two women receiving 4-HPR 200 mg/daily and 28 untreated controls entered the study. IGF-I levels were determined after acid-ethanol extraction, on plasma obtained at randomization and after a mean time of 10.8 +/- 0.3 months. At baseline, there was no difference in IGF-I levels between the two groups [152.9 +/- 9.4 versus 159.2 +/- 7.0 ng/ml in treated and control group (P = 0.59), respectively]. After follow-up time, while plasma IGF-I levels were unchanged in control patients (163.3 +/- 7.4 ng/ml; P = 0.5), they were significantly reduced to 134.6 +/- 8.1 ng/ml in the patients treated with 4-HPR (P = 0.003 and P = 0.011 versus baseline and control values, respectively). Multiple regression analysis showed that treatment was the only determinant of IGF-I decline. Moreover, the interaction between treatment and age was significant, in that the decrease of IGF-I levels induced by 4-HPR administration was much more pronounced in younger patients, while an age-related decline was observed in controls. We conclude that the synthetic retinoid 4-HPR lowers circulating IGF-I levels in early breast cancer patients. Although the importance of this observation for the clinical prevention of breast cancer remains to be established, it further substantiates the rationale of the combination of 4-HPR with tamoxifen, which is known to decrease IGF-I as well and to act synergistically with the retinoid in preclinical models.
Fenretinide (4-HPR), a synthetic derivative of retinoic acid, has proven effective at inhibiting in vitro breast cancer cell growth and preventing the progression of chemically induced mammary carcinoma in rodents. Our group has made a particular effort with regard to this molecule in clinical studies aimed at evaluating its pharmacology, toxicity, and efficacy in breast cancer prevention. We have demonstrated that 4-HPR blood levels remain constant during administration for as long as 5 years, that the drug accumulates in the human breast, and that it induces a significant decline of plasma insulin-like growth factor-I (IGF-I) levels. To date, 2,972 Stage I breast cancer patients have been randomized to evaluate the efficacy of a 5-year administration of 4-HPR to prevent new contralateral primary breast cancers. Compliance to protocol and treatment is high and tolerability of the drug is good; only 51 women out of 1,397 (3.6%) had to interrupt drug intake due to toxicity. The only potential limitation to the extensive use of 4-HPR is diminished dark adaptation, which occurs in about one-fourth of the patients and is dependent on the decline of plasma retinol below the threshold level of 100 ng/ml. Plasma levels of (4-methoxyphenyl)retinamide (4-MPR), the principal metabolite of 4-HPR, which are higher in elderly women with a high percentage of adipose tissue, are the major determinants of the retinol decrease. However, about 50% of the patients with altered dark-adaptometry are asymptomatic and the alterations are promptly reversible upon drug discontinuation.(ABSTRACT TRUNCATED AT 250 WORDS)