Unexpected hyperparathyroidism in metastatic renal cell carcinoma patients treated with sunitinib

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Background: Sunitinib malate is a tyrosine kinase inhibitor, active against tyrosine kinase receptors involved in tumour growth and angiogenesis, and is a potent substrate of p-glycoprotein. This study was conducted to assess whether sunitinib could affect phospho-calcium metabolism. This because both sunitinib and parathyroid hormone have been suggested to be substrates of p-glycoprotein. Here we report the incidence of newly onset hyperparathyroidism in a cohort of patients affected by metastatic renal cell carcinoma (mRCC), treated with sunitinib.

Methods: Parathyroid and calcium metabolism function tests were prospectively evaluated in patients receiving a daily 50 mg sunitinib for mRCC according to classic 6-week schedule. Between July 2008 and July 2010, 25 patients received a sunitinib treatment at our institution and resulted eligible for evaluation. Median patients age was 64.3 years old (range 48-79). Parathyroid hormone (PTH), serum and urinary phosphate and calcium, were measured at the beginning of treatment and at the end of each sunitinib ON period.

Results: During sunitinib therapy, 17 patients (68%) developed elevated serum parathyroid hormone, with low-to-normal serum calcium and phosphate. On average patients presented an elevation of PTH after 3 sunitinib cycles (range 1-5). Those presenting elevated PTH showed low or undetectable urinary calcium levels.

Conclusions: Hyperparathyroidism develops in a high percentage of patients undergoing sunitinib. A similar observation was reported among patients on imatinib, due to an inhibition of PDGF receptor both on osteoclasts and osteoblasts. In these patients, a temporary decrease of serum ionized calcium was supposed as the pathogenetic mechanism of hyperparathyroidism. As sunitinib inhibits PDGF receptors', similar events could be hypothesized. This observation suggests that abnormalities in bone metabolism are a common feature of tyrosine kinases inhibitors targeting PDGF receptors. Routine monitoring of bone metabolism during sunitinib therapy is therefore recommended.

No significant financial relationships to disclose.

Long-Term Survival in Metastatic Melanoma Patients Treated with Sequential Biochemotherapy: Report of a Phase II Study

The overall survival for patients with metastatic melanoma is very poor, with a median survival of 8.5 months. In this Phase II trial, we assessed the efficacy, safety, and tolerability of a sequential biochemotherapy schedule, using dacarbazine as antiblastic agent and immunomodulant doses of interleukin-2 and interferon-alfa. Thirty-one eligible patients with metastatic melanoma received dacarbazine IV as antiblastic therapy and interluekin-2, plus interferon-alfa SC as sequential immunotherapy, for 6 months. Responding and nonprogressing patients were subsequently maintained on immunotherapy treatment for further 6 months. Twenty-nine patients had an adequate trial, and were assessable for both response and toxicities, with a median follow-up of 49 months. The overall response rate was 52 percent (3 CR and 12 PR), SD was 8 (27 percent) and PD were achieved in 6 patients (21 percent). The median survival duration of responders was 28 months, significantly longer (p < 0.001) than the 16 months of nonresponders. Therapy was well tolerated and produced a significant improvement in progressive-free survival. Further studies, thus, are recommended for larger groups of patients not only to confirm these results, but also to apply this biochemotherapy regimen as adjuvant postsurgical treatment in early stages of malignant melanoma.

The effect of hydroxyurea on P-glycoprotein/BCRP-mediated transport and CYP3A metabolism of imatinib mesylate

PURPOSE

It has been reported that the combination therapy of imatinib mesylate, a tyrosine kinase inhibitor, plus hydroxyurea, a ribonucleotide reductase inhibitor, is associated with remarkable antitumor activity in patients with recurrent glioblastoma multiforme. However, the mechanism of the added activity of hydroxyurea to imatinib is not known. The purpose of this study was to investigate in vitro, whether hydroxyurea could enhance the central nervous system penetration of imatinib, by inhibition of the ATP-dependent transporter proteins P-glycoprotein (ABCB1; MDR1; Pgp) and Breast Cancer Resistance Protein (ABCG2; BCRP), or by inhibition of cytochrome P450 3A (CYP3A) metabolism of imatinib.

METHODS

The effect of hydroxyurea on the Pgp and BCRP mediated transport of imatinib was investigated by the sulforhodamine-B (SRB) drug cytotoxicity assay and transepithelial transport assay. In vitro biotransformation studies with supersomes expressing human CYP3A4 were performed to investigate whether hydroxyurea inhibited CYP3A4.

RESULTS

In both in vitro cytotoxicity and transport assays, hydroxyurea did not affect Pgp and BCRP mediated transport of imatinib. In a biotransformation assay, hydroxyurea had no influence on the metabolic degradation of imatinib either.

CONCLUSION

The results indicate that hydroxyurea does not interact with imatinib by inhibition of Pgp and BCRP mediated transport or by CYP3A4 mediated metabolism of imatinib.

Treatment of locally advanced hepatocellular carcinoma by hepatic intra-artery chemotherapy: a pilot study

BACKGROUND

Hepatocarcinoma is one of the most common malignant tumours world-wide with poor prognosis. Treatment of locally advanced hepatocarcinoma is still controversial. Transcatheter arterial (chemo-)embolisation of hepatocarcinoma are widely used methods but some aspects regarding their use and usefulness have not yet been clarified. Systemic remedies have not yet been proven to affect patient survival.

AIMS

To determine if intra-arterial chemotherapy with 5-flurouracil and folinic acid in locally advanced hepatocarcinoma is a viable alternative to existing therapies.

PATIENTS

Twenty-four inoperable consecutive patients with locally advanced hepatocarcinoma were enrolled. They all underwent intra-arterial chemotherapy via a surgically implanted port-a-cath, and folinic acid (100 mg/m2) and 5-flurouracil (up to 550 mg/m2) were administered with a 1-week or a 2-week schedule.

RESULTS

Nineteen patients completed the study: 2 showed a complete positive response, 11 a partial response, 6 stable disease, while 4 showed a disease progression. Median survival time was 19 (range 4-85) months. Child A patients showed a significant longer survival.

CONCLUSIONS

Intra-arterial chemotherapy using folinic acid and 5-flurouracil may be useful in the treatment of locally advanced hepatocarcinoma in cirrhotic patients even in the presence of thrombosis. This treatment could be also useful in comparing transarterial chemoembolisation to a curative treatment.

Heme oxygenase-1 and the ischemia-reperfusion injury in the rat heart

Carbon monoxide (CO) is a signaling gas produced intracellularly by heme oxygenase (HO) enzymes using heme as a substrate. During heme breakdown, HO-1 and HO-2 release CO, biliverdin, and Fe(2+). In this study, we investigated the effects of manipulation of the HO-1 system in an in vivo model of focal ischemia-reperfusion (FIR) in the rat heart. Male Wistar albino rats, under general anesthesia and artificial ventilation, underwent thoracotomy, the pericardium was opened, and a silk suture was placed around the left descending coronary artery; ischemia was induced by tightening the suture and was monitored for 30 min. Subsequently, the ligature was released to allow reperfusion lasting for 60 min. The first group of rats was sham operated and injected intraperitoneally (i.p.) with saline. The second group underwent FIR. The third group was treated ip 18 hr before FIR with hemin (4 mg/kg). The fourth group was pretreated ip 24 hr before FIR and 6 hr before hemin with zinc protoporphyrin IX (ZnPP-IX, 50 microg/kg). Specimens of the left ventricle were taken for determination of HO expression and activity, infarct size, malonyldialdehyde (MDA) production, and tissue calcium content. FIR led to a significant increase in the generation of MDA and notably raised tissue calcium levels. Induction of HO-1 by hemin significantly decreased infarct size, incidence of reperfusion arrhythmias, MDA generation, and calcium overload induced by FIR. These effects were prevented by the HO-1 inhibitor ZnPP-IX. The present experiments show that the concerted actions of CO, iron, and biliverdin/bilirubin modulate the FIR-induced myocardial injury.

Tamoxifen in the treatment of hepatocellular carcinoma: 5-year results of the CLIP-1 multicentre randomised controlled trial

BACKGROUND

In 1998, when data of a meta-analysis on tamoxifen in the treatment of hepatocellular carcinoma (HCC) had suggested a little advantage for this treatment, we published the results of a multicenter randomised controlled trial, that showed no survival benefit for tamoxifen vs. control. Here we report an updated analysis of the study results 4.5 years after the closure of enrollment.

METHODS

The study had a planned sample size of 480 patients. Patients with any stage HCC were eligible, irrespective of locoregional treatment. Tamoxifen was given orally, 40 mg/die, from randomisation until death.

RESULTS

496 patients were randomised by 30 Institutions from January 1995 to January 1997. Information was available for 477 patients. As of July 2001, 374 deaths (78%) were recorded, and median survival times were 16 and 15 months (p=0.54), in the control and tamoxifen arm. Data were further analysed separately for advanced patients and for those eligible to potentially curative locoregional treatments: relative hazard of death for patients receiving tamoxifen was equal to 0.98 (95% CI 0.76-1.25) for the former group and 1.38 (95% CI 0.95-2.01) for the latter. The prognostic score recently devised by our group (CLIP score) was, as expected, strictly correlated (p<0.0001) to the locoregional treatment received and strongly correlated with prognosis.

CONCLUSIONS

the update of the present study confirms that tamoxifen is not effective in prolonging survivals, both in advanced patients and in those potentially curable and that the CLIP score is able to predict prognosis.

Up-regulation of cyclooxygenase 2 gene expression correlates with tumor angiogenesis in human colorectal cancer

BACKGROUND & AIMS

Recent studies have shown that cyclooxygenase (COX)-2 and its products, prostaglandins (PGs), may be involved in colorectal carcinogenesis. The aim of this study was to determine whether COX-2 expression and PGE(2) production correlate with microvessel density, vascular endothelial growth factor (VEGF) expression, and tumor metastasis in human colorectal cancer.

METHODS

Tumor samples and adjacent normal mucosa were obtained from 31 surgical specimens. Immunohistochemical expression of COX-2, VEGF, and CD31 was analyzed on paraffin-embedded tissue sections. COX-2 and COX-1 proteins were determined by Western blot analysis. COX-2 and VEGF messenger RNA expressions were evaluated using Northern blot analysis. PGE(2) production was determined by specific radioimmunoassay.

RESULTS

The immunohistochemical expressions of both COX-2 and VEGF were significantly correlated with microvessel density (P = 0.02 and P = 0.002, respectively). A significant correlation was found between COX-2 and VEGF expression (P = 0.004). Western analysis confirmed the up-regulation of COX-2 protein expression. COX-2 and VEGF genes were overexpressed in tumor specimens as compared with normal mucosa. PGE(2) levels were significantly higher in metastatic tumors than in nonmetastatic ones (P = 0.03).

CONCLUSIONS

COX-2 is related to tumor angiogenesis in colorectal cancer. It is likely that VEGF is one of the most important mediators of the COX-2 angiogenic pathway.

Randomized trial of adjuvant chemotherapy versus control after curative resection for gastric cancer: 5-year follow-up

Adjuvant chemotherapy of gastric cancer after curative resection is still subject to discussion. In this study 137 patients with gastric adenocarcinoma, all with positive nodes, were randomized after curative resection so that 69 received epidoxorubicin (EPI), leucovorin (LV) and 5-fluorouracil (5-FU) on days 1-3 every 3 weeks for 7 months, whereas the remaining 68 did not. After a follow-up period of 5 years, 21 of the 69 treated patients (30%) and nine controls (13%) were still alive; median survival time was 18 months for the controls and 31 months for the patients treated with adjuvant chemotherapy (P< 0.01).

Reflux and pH: 'alkaline' components are not neutralized by gastric pH variations

The ability of the 'alkaline' components of reflux to cause harm in vivo is still open to debate, although these components have been shown in vitro to be capable of damaging the mucosa. The precipitation of bile acids and lysolecithin that occurs at low pH values is the main reason for questioning in vivo mucosal damage. This study was undertaken to determine the composition of gastric aspirates at different original pH values and the degree of solubility of the alkaline components when pH modifications are artificially induced. The samples for chemical analysis were collected from indwelling nasogastric tubes after surgical procedures that did not involve the upper gastrointestinal tract. Bile acid and lysolecithin concentrations were assessed by means of dedicated methods. Thirty-five samples were available for bile acid evaluation and 27 for lysolecithin evaluation. Bile acid and lysolecithin assessments were repeated after pH adjustment at 2, 3.5, 5.5 and 7. For easier assessment of the results, three ranges of the original pH were selected (pH < 2, 2 < or = pH < 5, pH > or = 5). For each pH range, results were pooled together and compared with those in the other pH ranges. Bile acid concentrations were 113+/-48, 339+/-90 and 900+/-303 (mean +/- s.e.m. micromol/L), respectively, in the three groups selected on account of the different original pH values. Differences were significant (p < 0.001). Both taurine- and glycine-conjugated bile acids were represented even at pH < 2. No major differences were observed in bile acid concentration with the artificially induced pH variations. Lysolecithin concentrations were 5.99+/-3.27, 30.80+/-8.43 and 108.37+/-22.17 (mean +/- SEM microg/ml), respectively, in the three groups selected on account of the different original pH ranges. Differences were significant (p < 0.001). No significant differences in lysolecithin concentration were detected with the artificially induced pH variations. In conclusion, both bile acids and lysolecithin are naturally represented in the gastric environment even at very low pH values, although their concentrations decrease on lowering of the naturally occurring pH. Given the concentration variability of bile acids and lysolecithin, further studies are needed to assess the minimal concentration capable of mucosal damage in vivo.

Gross pathologic types of hepatocellular carcinoma in Italy

The prevalence and independent predictors of the different macroscopic types of hepatocellular carcinoma (HCC) were assessed in 1,073 unselected patients of 14 hospitals in Italy from May 1996 to May 1997. Solitary HCC was the most common cancer type (44.6%), followed by multinodular (44.2%), diffuse (8.4%) and massive (2.8%) types. After adjustment for the influence of confounders by multiple logistic regression analysis, Child-Pugh grades B and C were found to be independent predictors of multinodular (odds ratio, OR, 2.0; 95% confidence interval (CI) = 1.5-2.6) and diffuse (OR 2.6; 95% CI = 1.6-4.4) HCC types. These findings indicate that the majority of HCC cases are not detected at a potentially treatable stage. Delayed detection of HCC is associated with a higher likelihood of the multinodular or diffuse gross pathologic type.

Characteristics of hepatocellular carcinoma in Italy

BACKGROUND/AIMS

This study aimed to assess the main features of hepatocellular carcinoma at the time of diagnosis in Italy, particularly in relation to the presence or absence of underlying cirrhosis, hepatitis virus marker patterns, age of the subjects and alpha-foetoprotein values.

METHODS

A total of 1148 patients with hepatocellular carcinoma seen at 14 Italian hospitals in the 1-year period from May 1996 to May 1997 were the subjects of this prevalence study. Both newly diagnosed cases (incident cases) and cases diagnosed before May 1996 but still attending the hospitals during the study period (prevalent cases) were included.

RESULTS

We found that 71.1% of cases were positive for hepatitis C virus antibodies but negative for HBsAg; in contrast, 11.5% were negative for anti-HCV but positive for HBsAg; 5.3% were positive for both markers; and 12.1% were negative for both viruses. The mean age of detection was over 60 years, with a younger mean age in HBsAg-positive compared to anti-HCV-positive patients (59.3 years vs. 65.6 years, p<0.01). The male-to-female ratio among HBsAg-positive patients was 10.4:1, in contrast to 2.8:1 among anti-HCV-positive patients (p<0.01). The majority of cases (93.1%) had underlying cirrhosis. Cirrhotic patients were more likely to be anti-HCV positive than non-cirrhotic cases (73.2% vs 43.9%; p<0.01); conversely, absence of hepatitis virus markers was more frequently observed in the non-cirrhotic than in the cirrhotic population (40.9% vs. 10.0%; p<0.01). Overall, the alpha-foetoprotein level was altered (>20 ng/ml) in 57.9% of patients; only 18% of cases presented diagnostic (>400 ng/ml) values. Anti-HCV positivity (O.R. 2.0; CI 95%=1.3-3.1) but not HBsAg positivity (O.R. 1.0; CI 95%=0.6-1.8) was shown to be an independent predictor of the likelihood of altered alpha-foetoprotein values by multivariate analysis.

CONCLUSIONS

These findings point to differences in the characteristics of the populations infected by hepatitis B and hepatitis C. Factors other than the hepatitis viruses are important in non-cirrhotic patients. A change in the relative prevalence of hepatitis virus markers among hepatocellular carcinoma cases was demonstrated, reflecting a significant change in the rate of HBV endemicity in the Italian population. Finally, the increased trend in the mortality rate from liver cancer in Italy from 4.8 per 100,000 in 1969 to 10.9 in 1994 may reflect the large cohort of subjects infected with HCV via the iatrogenic route during 1950s and 1960s when glass syringes were commonly used for medical treatment.

Respiratory mechanics in patients with tense cirrhotic ascites

Lung volumes are decreased by tense ascites and increase after large volume paracentesis (LVP). The overall effect of ascites and LVP on the respiratory function is poorly understood. We studied eight cirrhotic patients with tense ascites before and after LVP. Inspiratory muscle force (maximal transdiaphragmatic pressure (Pdi,max), and the lowest pleural pressure (Pp1,min)) was assessed while the patients were seated. Rib cage and abdominal volume displacements, as well as pleural and gastric pressures were measured during quiet breathing while the patients were supine. Pdi,max and Ppl,min were normal and did not change after LVP (from 84.2+/-19.7 to 85.2+/-17.0 cmH2O and from 68.3+/-19.7 to 74+/-15.9 cmH2O, respectively). The abdominal contribution to the generation of tidal volume was greater than that of the rib cage (79 vs 21%), a pattern which did not change after LVP (73 and 27%). Before LVP, tidal swings both of pleural pressure (Ppl,sw) and transdiaphragmatic pressure (Pdi,sw) were large (15.3+/-4.3 and 18.5+/-3.9 cmH2O, respectively) and the load on inspiratory muscles was increased as a consequence of elevated dynamic elastance of the lung (El,dyn) (11.4+/-2.6 cmH2O x L(-1)) and ("intrinsic") positive end-expiratory pressure (PEEPi) (4.3+/-3.5 cmH2O). LVP reduced the load on the inspiratory muscles, as shown by the significant decrease in Ppl,sw (10.6+/-2.0 cmH2O), Pdi,sw (12.8+/-3.0 cmH2O), El,dyn (10.0+/-2.0 cmH2O x L(-1)) and PEEPi (1.1+/-1.3 cmH2O). The amount of fluid removed was closely related to changes in Ppl,sw and PEEPi. We conclude that the strength of the inspiratory muscles is normal or reduced in seated cirrhotic patients. In the supine position, tense ascites results in an increase in lung elastic load and development of positive end-expiratory pressure, with a consequent overload and increased activation of inspiratory muscles. Large volume paracentesis decreases overloading and activation, but does not change the strength of the inspiratory muscles.

Long course and prognostic factors of virus-induced cirrhosis of the liver

OBJECTIVE

Chronic infection by hepatitis B virus (HBV) and hepatitis C virus (HCV) is now recognized as a major cause of liver cirrhosis. This study was aimed at evaluating the natural history of the disease in a large series of Italian patients with HBV- and HCV-related cirrhosis without portal hypertension at entry.

METHODS

The clinical records of 405 patients (233 males, mean age 54 +/- 9 yr) with histologically proven cirrhosis (321 with HCV-related and 84 with HBV-related cirrhosis) and no clinical evidence of portal hypertension at entry were retrospectively examined to evaluate the occurrence of complications and the cumulative mortality rate during follow-up.

RESULTS

Patients had a mean follow-up of 8 +/- 3 yr. The cumulative survival rate was 99.1% at 5 yr, 76.8% at 10 yr, and 49.4% at 15 yr. The age-adjusted death rate was 3.14 and 2.84 times higher than in the general Italian population in men and women, respectively. Only the bilirubin level was an independent indicator of survival. Esophageal varices, ascites, jaundice, hemorrhage, hepatic encephalopathy, and hepatocellular carcinoma significantly reduced the survival rate (major complications), whereas thrombocytopenia, diabetes, and cholelithiasis did not affect survival (minor complications). The incidence of hepatocellular carcinoma was similar in patients with either HBV- or HCV-related disease and was quite frequent, especially in males.

CONCLUSIONS

This study demonstrates that the course of virus-induced liver cirrhosis is not influenced by the etiology of the disease and that the occurrence of complications significantly shortens life expectancy. The longer survival rate observed in this study is probably due to the fact that cirrhosis was here recognized by liver biopsy in the absence of clinical evidence of portal hypertension.

Chronic viral hepatitis induced by hepatitis C but not hepatitis B virus infection correlates with increased liver angiogenesis

Chronic hepatitis B virus (HBV) and hepatitis C virus (HCV) infections lead to cirrhosis and increase the risk for the development of hepatocellular carcinoma (HCC). Angiogenesis is an essential step in oncogenesis and contributes to tumor progression in adult organs; however, to what extent angiogenesis occurs in the liver during chronic viral hepatitis has not been studied. Ninety-nine matched patients affected by chronic hepatitis due to either HBV or HCV were studied together with 13 controls (5 patients were affected by familial hyperbilirubinemia with normal liver histology; 6 patients with stage II primary biliary cirrhosis; and 2 patients with pseudo inflammatory tumor). Microvessel density was assessed in liver biopsies by immunostaining using two different antibodies against endothelial cell antigens, QB-END/10 and Factor VIII. In addition, the liver homogenates and sera of HCV- or HBV-positive patients and controls were tested for their capacity to stimulate the migration and proliferation of freshly isolated human endothelial cells in vitro. Evidence of angiogenesis was significantly more frequent in HCV-positive patients compared with HBV-infected subjects or controls (74% vs. 39% vs. 8%) (chi2 = 20.78; P < .0001) (HCV+ vs. HBV+ vs. controls). The degree of microvessel density was also higher in HCV- than in HBV-positive patients or controls (chi2 = 12.28; P < .005). In addition, HCV-positive sera and liver homogenates stimulated a higher migration and proliferation of human endothelial cells in vitro compared with HBV-positive or control sera and liver homogenates. These observations indicate that angiogenesis is particularly linked to HCV infection, suggesting a possible contribution to HCV-related liver oncogenesis.

[Viral liver cirrhosis: natural course, pathogenesis and clinical implications of the complications]

The role of hepatitis B virus (HBV) and hepatitis C virus (HCV) as a major cause of chronic liver disease is now accepted worldwide. This study was aimed at evaluating the natural history of the disease in patients with virus-induced chronic active hepatitis or cirrhosis, and the influence played by age, sex and etiology, liver function tests and by the occurrence of different complications. We retrospectively examined the clinical records of 506 inpatients: 194 were affected by chronic active hepatitis (125 males, 69 females, mean age 45 +/- 11 years, 146 HCV- and 48 HBV-related), and 312 by cirrhosis without clinical evidence of portal hypertension (178 males, 134 females, mean age 53 +/- 9 years, 249 HCV- and 63 HBV-related). The occurrence of cirrhosis in the chronic active hepatitis group was then calculated, together with the occurrence of complications and the cumulative mortality rate of established cirrhosis. During follow-up 93 patients with chronic hepatitis developed cirrhosis. The cumulative probability of developing cirrhosis in this group was 6.64% at 5 years, 56.1% at 10 years and 86.8% at 15 years. These patients were therefore included in the cirrhosis group for the final analysis, so that a total of 405 cirrhotic patients were evaluated: these patients had a cumulative survival rate of 99.1% at 5, 76.8% at 10 and 49.4% at 15 years. Comparing the age-adjusted death rate of our patients with the general Italian population, we observed that in patients with liver cirrhosis it was 3.14 and 2.84 times higher in men and women, respectively. Bilirubin was an independent indicator of survival. Several complications, such as esophageal varices, ascites, jaundice, hemorrhage, hepatic encephalopathy and hepatocellular carcinoma significantly reduced the survival rate and were indicated as major complications, while thrombocytopenia, cholelithiasis and diabetes did not affect survival and thus were called minor complications. Incidence of hepatocellular carcinoma was very high especially in males, without correlation with etiology. In conclusion, the progression of virus-induced chronic active hepatitis to cirrhosis is not influenced by sex and etiology. Similarly, the different etiology does not modify the natural history of cirrhosis while the occurrence of one or more major complications significantly shortens survival. The longer survival rate observed in patients with cirrhosis included in this study is probably due to the selective inclusion of patients with early disease and no evidence of portal hypertension.

Conferring drug resistance by MDR1 gene transfection increases susceptibility to irradiation and lipid peroxidation in 3T3 cell line

This study was performed to test the hypothesis that conferring multiple drug resistance reduces cell susceptibility to irradiation and iron-stimulated lipid peroxidation. Multidrug resistant (PN1A) and parental drug sensitive (PSI-2) cell lines were exposed to ADP-Fe or Ascorbate-Fe complexes at 37 degrees C and to irradiation. Lipid peroxidation was estimated by the TBA test, whereas x-ray effect was estimated by clonogenic assay. Cell glutathione-S-transferase (GST), total and Se-dependent glutathione peroxidase (GSH-Px) activities, and glutathione and vitamin E were measured. PN1A produced more peroxides than PSI-2 after exposure to iron complexes and formed fewer colonies after irradiation. Higher activities of GST and total and Se-GSH-Px were observed in PN1A. Vitamin E and total glutathione did not differ in the two cell subclones. These data show that the induction of the mdr1 phenotype by transfection of mdr1 gene in 3T3 cells increases susceptibility to irradiation and iron stimulated lipid peroxidation.

Susceptibility to lipid peroxidation of human hepatocellular carcinoma cell lines with different levels of multiple drug-resistant phenotype

BACKGROUND

It has not been established whether the presence of intrinsic or acquired multiple drug-resistant (MDR) phenotype affects susceptibility to undergo iron-stimulated lipid peroxidation.

EXPERIMENTAL DESIGN

To assess this point, human hepatocellular carcinoma cell lines with moderate, clinically relevant (P1) or elevated (P1(0.5)) MDR phenotype and their parental drug-sensitive (P5) cell line were exposed to ADP-Fe or ascorbate-Fe complexes and H2O2 in different experiments. Thiobarbituric acid-reactive substances (TBARS) were measured. Total cell glutathione, glutathione-S-transferase, total and selenium-dependent glutathione peroxidase activities, and cell alpha-tocopherol content were also determined.

RESULTS

P5 and P1 cell lines showed similar and significant formation of TBAR after 1-hour incubation exposure to iron complexes, whereas P1(0.5) subclone did not. No accumulation of TBAR was observed during the exposure to H2O2 in the three cell lines. Among antioxidants, only alpha-tocopherol cell content was significantly higher in P1(0.5) in comparison with either P1 or P5.

CONCLUSIONS

These data suggest that MDR phenotype development per se does not increase resistance to iron-related free radical attack in human hepatocellular carcinoma cell lines. Resistance to undergo lipid peroxidation is associated only to high degrees of drug resistance and appears more related to increased alpha-tocopherol cell content rather than an MDR phenotype.

Bile acid inhibition of P-glycoprotein-mediated transport in multidrug-resistant cells and rat liver canalicular membrane vesicles

To study the effect of bile acids on P-glycoprotein-mediated drug transport, we performed experiments using multidrug resistant cells and rat canalicular membrane vesicles. Cellular accumulation and efflux of rhodamine 123 were measured in drug-resistant cells by means of computerized quantitative image analysis and fluorescence microscopy. ATP-dependent [3H]daunomycin transport was studied by means of rapid filtration in canalicular membrane vesicles prepared from normal rats. Doxorubicin-sensitive (PSI-2) and -resistant (PN1A) 3T3 cells and human-derived hepatocellular carcinoma doxorubicin-sensitive and -resistant cells were used. Taurochenodeoxycholate and glycochenodeoxycholate, taurolithocholate and ursodeoxycholate (50 to 200 mumol/L) inhibited rhodamine 123 and [3H]daunomycin transport in multidrug-resistant cells and canalicular membrane vesicles, respectively, whereas taurocholate, taurodeoxycholate and tauroursodeoxycholate did not. Primary and secondary unconjugated bile acids had no effect. These results reveal that taurolithocholate, taurochenodeoxycholate and glycochenodeoxycholate and ursodeoxycholate inhibit P-glycoprotein-mediated drug transport function in multidrug resistant cell lines and in canalicular membrane vesicles. These results suggest possible interaction between P-glycoprotein function and bile acids in cholestasis and after treatment of patients with ursodeoxycholic or chenodeoxycholic acid.

"Inapparent" hepatitis B virus infection and hepatitis C virus replication in alcoholic subjects with and without liver disease

We evaluated hepatitis B virus DNA and hepatitis C virus RNA in sera from 110 HBsAg and IgM HBc antibody-negative heavy drinkers (50 cirrhosis, 13 chronic active hepatitis, 25 fatty liver with or without mild to moderate fibrosis, alcoholic hepatitis or both and 22 healthy alcoholic subjects) with polymerase chain reaction. Results of hepatitis C virus polymerase chain reaction were compared with those obtained with two tests (second generation recombinant immunoblot assay and enzyme-linked immunosorbent assay) used to detect hepatitis C virus antibodies. Hepatitis B virus DNA was found in three (2.7%) patients. Hepatitis C virus RNA was detected in 29 (29.8%) of the 97 subjects whose sera were well preserved for RNA extraction (42.5% cirrhosis, 83.3% chronic active hepatitis, 8% fatty liver and 0% healthy alcoholic subjects). Results obtained with second-generation recombinant immunoblot assay and enzyme-linked immunosorbent assay had a high degree of agreement with polymerase chain reaction as expected, the kappa indexes being 0.76 and 0.61, respectively. Nevertheless, five hepatitis C virus RNA-positive patients had negative recombinant immunoblot assay results, whereas all hepatitis C virus RNA-positive patients had positive or borderline enzyme-linked immunosorbent assay results. We conclude that, in Italian HBsAg-negative alcoholic patients, "inapparent" hepatitis B virus infection is rare. On the contrary, hepatitis C virus infection, as detected on hepatitis C virus polymerase chain reaction, is quite frequent, especially in patients who have cirrhosis and chronic active hepatitis.(ABSTRACT TRUNCATED AT 250 WORDS)

[The pathogenetic mechanisms of intrahepatic cholestasis]

The present review firstly gives some details regarding nosological approach to the cholestatic syndrome. In addition, different steps are considered, identifying 12 possible metabolic defects responsible for determining a cholestatic syndrome either in man or in experimental conditions. Eleven defects out of these 12 steps should be considered related to the structure and function of the hepatocyte, whereas the twelfth one, which comprises 3 different sub-groups, is based on a mechanical obstructive mechanism, localized exclusively into the liver parenchyma, thus resembling the other ones included in the chapter of intrahepatic cholestasis.

Long-term ambulatory enterogastric reflux monitoring. Validation of a new fiberoptic technique

A new technique for the long-term ambulatory detection of enterogastric and nonacid gastroesophageal reflux has been conceived, developed, and validated. It is based on the use of a fiberoptic sensor that utilizes the optical properties of bile. In vitro studies have shown good precision, good stability, sensitivity of 2.5 mumol/liter bilirubin concentration, as well as a useful working range of 2.5-100 mumol/liter bilirubin concentration. In vivo studies have been performed in 29 subjects. Simultaneous gastric aspirations have allowed a comparison of fiberoptic system measurements both with spectrophotometric analysis and bile acid concentrations of corresponding gastric juice samples. Linear correlations were shown between fiberoptic assessment and both spectrophotometric and bile acid concentration findings (P < 0.01). Simultaneous assessment of reflux with the fiberoptic system and cholescintigraphy has shown a 92.9% concordance as regards the presence or absence of reflux. Present results imply that the fiberoptic system is an important tool for the understanding of the clinical relevance of enterogastric and nonacid gastroesophageal reflux.

Reflux-related gastric mucosal injury is associated with increased mucosal histamine content in humans

BACKGROUND

Experimental studies in the dog and the rat have shown histamine involvement in reflux-related gastric mucosal injury. However, no definite demonstrations of a link between reflux-related gastric mucosal injury and mast cell mediators exist in humans.

METHODS

The relationships between reflux, gastric mucosal histamine content, and gastric histology were assessed in partially gastrectomized subjects presumptively with high (11 Billroth II subjects) and low reflux levels (9 total biliary diversion subjects), respectively. Findings were compared with those in a control group consisting of 8 endoscopically and histologically proven normal subjects.

RESULTS

Bile acid quantity and concentration in the gastric aspirates were significantly greater in Billroth II subjects than in total biliary diversion subjects. Significantly higher cumulative scores for foveolar hyperplasia, mucosal edema, capillary dilatation and congestion, and smooth muscle fibers in the lamina propria were found in Billroth II subjects than in total biliary diversion subjects. Mucosal histamine content as well as mast cell density and degranulation differed significantly between Billroth II and the other two groups.

CONCLUSIONS

These results represent the first demonstration in humans of an association between mast cell mediators and chemical gastric mucosal injury.

Acute phase proteins in alcoholics with or without liver injury

Acute phase proteins behaviour has been examined in chronic alcoholics to verify the hypothesis that chronic alcohol consumption stimulates the hepatic synthesis of acute phase proteins. Certain acute phase proteins were studied in two groups of alcoholics, one with and one without liver damage, and in a third group of healthy volunteers. The results show that the acute phase proteins were similar in the two groups of alcoholics, but differed when compared to the control group. The authors have concluded from these results, that chronic alcohol consumption causes a serum increase of: mucoproteins (p less than 0.001), alpha 1 acid glycoprotein (p less than 0.05), haptoglobin (p less than 0.05) and fibrinogen (p less than 0.02). Such increases are independent from the existence of liver damage.

Benzquinamide inhibits P-glycoprotein mediated drug efflux and potentiates anticancer agent cytotoxicity in multidrug resistant cells

We have previously shown that efflux of cytotoxic drugs from multidrug resistant (MDR) cell lines can be quantitated at the single cell level using a sensitive fluorescence microscopy technique. Based on the structure of compounds which inhibited the efflux of Rhodamine-123 (Rho-123) using this methodology, we hypothesized that the antiemetic, antihistaminic agent benzquinamide (BZQ) would interfere with P-glycoprotein (P-gp) mediated drug transport and potentiate the effects of anticancer agents in MDR cell lines. We show that BZQ interferes with P-gp mediated drug efflux and increases drug accumulation in MDR cells using Rho-123 as a fluorescent probe. BZQ increases the cytotoxicity of chemotherapeutic agents to both human and hamster MDR cell lines in vitro. A slight increase in cytotoxicity to chemotherapeutic agents is also observed in the parental cell lines with BZQ. BZQ increases [3H]daunorubicin accumulation and inhibits the binding of [125I]iodoaryl azidoprazosin to the P-gp in MDR cells. BZQ is a new agent to increase the cytotoxic effects of anticancer agents in MDR cells and may ultimately prove useful as an adjunct in cancer chemotherapy.

Gastric cell proliferation kinetics and bile reflux after partial gastrectomy

Thirty-four randomized, partially gastrectomized subjects (12 with a Billroth II, 11 with a Billroth I, and 11 with a total biliary diversion reconstruction) were studied in order to assess the relationships between bile reflux, gastric histology, and cell proliferation kinetics. Bile acid quantity and concentration in the gastric aspirates progressively decreased from Billroth II to Billroth I to total biliary diversion (after which reflux was almost absent). Perianastomotic mucosa in Billroth II subjects showed the greatest degree of foveolar hyperplasia, and this decreased markedly with increasing distance from the anastomosis. Hyperplastic changes were less evident in Billroth I, and virtually absent in total biliary diversion subjects. The overall foveolar hyperplasia-like behavior of cell kinetic parameters (total pit cell number, labeled pit cell number, and labeling index) was shown. Moreover, subjects with mean bile acid concentration greater than 150 mumol/L had both a greater prevalence of foveolar hyperplasia and greater values of cell kinetic parameters than those with mean bile acid concentration less than or equal to 150 mumol/L. A superficialization of the proliferative compartment was also evident in the former group. These results show a close relationship between postgastrectomy bile reflux, foveolar hyperplasia, and cell kinetic parameters. Histologic and cell kinetic findings are probably the expression of gastric adaptation to chronic bile reflux exposure. Moreover, the type and entity of cell kinetic involvement and its relationship to foveolar hyperplasia and reflux may suggest new "tools" in post-gastrectomy surveillance and help to clarify patterns of gastric carcinogenesis.

Acute and chronic exposure to ethanol and the electrophysiology of the brush border membrane of rat small intestine

In this study we have investigated the effects of (a) chronic ethanol intake on glucose and galactose absorption across the rat jejunum in vivo and on the potential difference across the isolated brush border membrane (Vm) and (b) acute exposure to ethanol (4% or 8%) and acetaldehyde (0.25%) on changes in Vm associated with Na(+)-dependent galactose absorption across the jejunum and ileum. Chronic ethanol intake was associated with hyperpolarization of Vm and an enhanced galactose but not glucose transport. Acute ethanol and acetaldehyde were without effect on Vm whether or not galactose was present. We conclude that while a greater electrochemical gradient across the brush border membrane is a likely explanation for the stimulation of galactose absorption induced by ethanol feeding, factors other than changes in Vm are responsible for the inhibitory effects of acute ethanol.

[The impacted canine in orthodontics]

The Authors after statistic elaborations about 6343 cases of impact tooth treated in Division of Odontostomatology and Maxillo-Face Surgery Regional Hospital "Umberto 1." of Ancona from 1974 to 1988 pay attention about the impact canine. They explay about the operative protocol that they divided in orthodontic and surgery times, emphatised the scrupulous execution of protocol to take a final success.

Hepatic lipid peroxidation and aldehyde dehydrogenase activity in alcoholic and non alcoholic liver disease

It has been suggested that lipid peroxidation plays a role in the pathogenesis of chronic alcoholic liver disease (CALD). However, whether or not CALD differs from chronic non alcoholic liver disease (CLD) in lipid peroxidation, is still questionable. Thirty-eight patients affected by CALD and CLD who were matched for age, sex, nutrition and liver function tests (LFTs) and 17 controls (C) took part in this study. The following tests were performed: serum and liver malondialdehyde (MDA) determination by the TBA test, liver total glutathione (GSH) estimate, mitochondrial (ALDH2) and cytosolic (ALDH1) aldehyde dehydrogenase activity determinations. Patients who showed signs of malnutrition were excluded from this study. Serum and hepatic TBA-reactive substances resulted in a slight increase in chronic liver patients compared to controls but did not show any difference between CALD and CLD groups. Liver total glutathione did not show any change. Hepatic ALDH2 activity was significantly (P less than 0.01) higher in CALD than in CLD and control patients whereas ALDH1 did not show any difference. These results suggest that the increased lipid peroxidation in CALD and in CLD is probably secondary to liver damage rather than being the pathogenic factor.

Short-term effects of bile diversion on postgastrectomy gastric histology

Twelve partially gastrectomized subjects who have consecutively undergone total biliary diversion for severe bilious vomiting were studied before and after operation in order to assess the effects of surgery on gastric histology and enterogastric reflux. Before and six months after operation, the following protocol was performed: (1) blood examinations including serum basal gastrin; (2) endoscopy with multiple gastric biopsies; and (3) quantitation of bile acids in the gastric aspirate. Of the preoperative symptoms, bilious vomiting and heartburn completely disappeared postoperatively in all the subjects. Fasting bile reflux was significantly reduced (bile reflux was annulled in six and considerably lowered in the remaining six subjects), and erythema of the gastric mucosa completely disappeared in all the subjects after diversion. Among histological findings, while a significant regression of foveolar hyperplasia was found both in the perianastomotic area and in the body of gastric remnant, none of the other aspects identifiable in postgastrectomy gastric mucosa (chronic gastritis changes included) were affected by diversion. These results show that biliary diversion is effective in correcting reflux, bilious vomiting, erythema, and foveolar hyperplasia of the gastric mucosa and confirm the suggested relationship between bile reflux and gastric foveolar hyperplasia.

Gastric histology and fasting bile reflux after partial gastrectomy

Forty-four randomized, partially gastrectomized subjects were studied to assess whether gastric histologic findings after partial gastrectomy were related to reflux. Gastric biopsy specimens (12) were taken at different distances from the anastomosis. Histologic findings were as follows: (a) hyperplastic changes of the foveolar epithelium and (b) loss of the chief and parietal gland cells with atrophy of gastric glands (chronic atrophic gastritis). Hyperplastic changes typical of the perianastomotic area gradually decreased with increasing distance from the anastomosis. Hyperplastic changes showed a greater prevalence in Billroth II than in Billroth I subjects (100% vs. 29.4%). No significant association was found between histologic findings and symptoms. Hourly bile acid quantity (fasting bile reflux) and concentration were determined in the gastric aspirates. Bile reflux was greater after Billroth II than after Billroth I (fasting bile reflux median values: 30.5 vs. 0.18 mumol/h, respectively). The same was true for bile acid concentration (mean bile acid concentration median values: 624.9 vs. 17.5 mumol/L, respectively). Moreover, Billroth I subjects with hyperplasia had a greater quantity and concentration of reflux than those without hyperplasia (fasting bile reflux and mean bile acid concentration median values: 2.6 vs. 0.8 mumol/h and 4.7 vs. 2.7 mumol/L, respectively). These findings show that bile reflux is correlated with hyperplastic changes of the foveolar epithelium, but prevalence and severity of atrophic gastritis were not related to reflux. Therefore, although we failed to show any relationship between chronic atrophic gastritis and reflux, foveolar hyperplasia was shown to be reflux related.

Effect of chronic ethanol ingestion on enterocyte turnover in rat small intestine

Whether chronic ethanol ingestion significantly damages the small intestine remains controversial. To clarify this we have analysed the morphology of the small intestinal epithelium and quantified its renewal in chronically ethanol fed rats. Twenty adult male rats were pair fed for 28 days a nutritionally adequate liquid diet containing either ethanol as 36% of total calories or an isocaloric diet in which fat substituted for ethanol. Crypt cell production rate was determined in the jejunum and ileum by the metaphase arrest method. Weight gain and small intestinal morphology were similar in ethanol fed and control rats, but enterocyte turnover was significantly reduced in the jejunum (p less than 0.05) and ileum (p less than 0.01) of the ethanol fed rats. This effect of ethanol on the small intestine is probably systemic rather than local, because the changes in jejunum and ileum were similar, and it may contribute to the development of malnutrition in chronic alcoholics.

Effect of chronic ethanol intake on lactase activity and active galactose absorption in rat small intestine

The effects of feeding a nutritionally adequate liquid diet containing 5% ethanol to rats over a four week period on intestinal lactase activity and the kinetics of jejunal galactose absorption in vivo have been determined. Both lactase activity and the maximum capacity for active, saturable galactose absorption (Jmax) were increased significantly after chronic ethanol ingestion. In contrast, uptake of the sugar via the phlorhizin-insensitive (passive) route was unaffected by ethanol. Our results imply the presence of an increased maturity of the enterocyte population on the villus surface in response to ethanol. The relevance of this work to uptake studies in alcoholics is briefly discussed.

Chemotherapy of primary and secondary liver cancer: is it useful?

The therapeutic efficacy of three different antiblastic regimens was tested in patients affected by primary or secondary liver cancer. The association of cyclophosphamide and adriamycin gave the best results, despite no partial remission observed with any treatment. As regards the efficacy of antiblastic therapy in this type of tumor, we must conclude that the only detectable effect is a transient improvement of the course of the disease.

Expired hydrocarbons in patients with chronic liver disease

Fifty patients with various types of liver disease and twenty-one healthy subjects were examined for lipoperoxidation in vivo by gaschromatographic assay of volatile hydrocarbons (ethane, ethylene, propane, n-butane, n-pentane) in breath gases. In 15 patients with alcoholic cirrhosis the amount of expired pentane was greater than in all the other groups examined. No significant increase of exhaled ethane, in contrast, was detected in the same patients. These results seem to indicate that pentane is a more sensitive index than ethane for ethanol-induced lipoperoxidation. This simple and non-invasive method opens up promising new opportunities for clarifying in humans, the role of lipoperoxidation in ethanol-induced liver damage, as well as in other chronic liver disease.

The bromosulphthalein loading test in chronic alcoholic liver diseases

The BSP loading test was performed in 39 patients affected by alcoholic liver disease. The behaviour of some parameters of the hepatic BSP metabolism was observed(45th min retention percentage, plasma disappearance rate, K1 and K2 exponentials, K21, K12 and K32 transfer rates). The 45th min retention percentage was the most sensitive parameter in detecting liver disease. This parameter, PDR, K1 and K21 were the most reliable parameters in differentiating between the various forms of alcoholic liver disease(alcoholic steatosis, alcoholic chronic hepatitis, alcoholic cirrhosis).