Tissue CA-19.9 content in colorectal adenomas and its value in the assessment of dysplasia

BACKGROUND

occasionally, the risk of malignant transformation may be difficult to establish in adenomatous polyps due to the fact that they contain areas with variable grades of dysplasia. A measurement of tissue tumor markers may be useful to recognize these adenomas.

OBJECTIVES

the aims of this study were: to established firstly the relationship between carbohydrate antigen 19.9 (CA-19.9) content in the colorectal mucosa and the characteristics of polyps, and secondly, the diagnostic value of the formers measurement.

PATIENTS AND METHODS

tissue CA-19.9 concentration was measured in 155 colorectal samples obtained from 145 patients (21 normal mucosa; 113 adenomatous polyps; 21 adenocarcinoma). Cytosol CA-19.9 content was determined by enzyme-linked immunoadsorbant assay, and the measurement of this protein was achieved by quantitative assay. Tissue samples were also processed for histological examination.

RESULTS

we demonstrated that CA-19.9 levels in adenomatous polyps and adenocarcinomas were significantly higher than in the normal mucosa. These levels varied significantly according to polyp size, histological type, and grade of dysplasia. CA-19.9 contents were higher in polyps with a high risk of malignant transformation than in those with a low risk of severe dysplasia. The cut-off value 214 U/mg of protein properly differentiated both types of risk. The area under the receiver operating characteristic (ROC) curves showed that cytosol CA-19.9 levels allow classifying polyps according to their histological features.

CONCLUSIONS

we concluded that the measurement of CA-19.9 content in adenomatous polyps may be useful to classify these tumors and confirm the feasibility to separate adenomas into two groups: low and high risk of malignant change.

Autoimmune cholangitis, nosological location

Autoimmune cholangitis is an entity with a controversial nosological location. It has been defined as a setting of autoimmune chronic cholestasis, clinically, biochemically and histologically resembling primary biliary cirrhosis, although with a different immunological profile. It lacks antimitochondrial antibodies and instead usually presents other autoimmunity features, basically positivity to antinuclear antibodies. In this article, we discuss its nosological location based on descriptions published on this entity and comparisons with primary biliary cirrhosis.

Strategy for diagnosis and management in iron overload

When suspecting an iron overload condition, the transferrin saturation levels should be determined. Levels higher than 45% and serum ferritin in men and postmenopausal women exceeding 200 microg/l confirm the iron overload. Afterwards, the HFE protein genotype should be determined. If it is C282Y or C282Y/H63D, the diagnosis of hereditary hemochromatosis can be accepted as the cause of the iron overload. In the absence of said genotypes, the overload is secondary or not related to the HFE protein. In hereditary hemochromatosis, the degree of iron overload and organic lesions must be established. Liver biopsies are very useful for obtaining said information and for the first case, the determination of serum ferritin is very useful. When less than 1000 microg/l, normal transaminases and no hepatomegalies, a treatment can be started without the need for a liver biopsy. In absence of anemia, the treatment is based on phlebotomies, 400-500 ml a week until obtaining depletion of excess iron. In presence of anemia, the treatment is based on chelating agents, preferably subcutaneous administered 8 hours a day.

Porphyria cutanea tarda as a predictor of poor response to interferon alfa therapy in chronic hepatitis C

BACKGROUND

Porphyria cutanea tarda (PCT) is sometimes associated with hepatitis C virus chronic infection. The aim of this study was to describe the effect of interferon alfa (IFN-alpha) in the treatment of patients with chronic hepatitis C and PCT.

METHODS

We treated a total of 66 patients with chronic hepatitis C with IFN-alpha 2b (5 MU t.i.w.) for 12 months. Twenty-two of these patients suffered from PCT as well. These patients differed from patients without PCT in that they were men, past history of alcohol abuse and HFE gene mutations were more common and the source of infection was almost always unknown.

RESULTS

Sustained virologic response was obtained in 19.7% of the 66 treated patients, 27.3% in the non-PCT group and 4.5% in the PCT group (P < 0.05). This difference could not be ascribed to the difference in sex of patients, history of alcohol abuse, HCV genotype or iron status.

CONCLUSION

Multivariate logistic regression analysis revealed that PCT is independently and significantly associated with non-sustained response to IFNalpha therapy. In conclusion, patients with chronic hepatitis C and PCT rarely responded to IFNalpha treatment.

Reactive oxygen species mediate the down-regulation of mitochondrial transcripts and proteins by tumour necrosis factor-alpha in L929 cells

In this study, we show that reactive oxygen species production induced by tumour necrosis factor alpha (TNF-alpha) in L929 cells was associated with a decrease in the steady-state mRNA levels of the mitochondrial transcript ATPase 6-8. Simultaneously, the transcript levels of two nuclear-encoded glycolytic enzymes, glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and phosphofructokinase, were increased. These changes were associated with decreased protein levels of the ATPase subunit a (encoded by the mitochondrial ATPase 6 gene) and cytochrome c oxidase subunit II, and increased protein levels of phosphofructokinase. Since TNF-alpha had no effect on the amount of mitochondrial DNA, the results suggested that TNF-alpha acted at the transcriptional and/or post-transcriptional level. Reactive oxygen species scavengers, such as butylated hydroxianisole and butylated hydroxytoluene, blocked the production of free radicals, prevented the down-regulation of ATPase 6-8 transcripts, preserved the protein levels of ATPase subunit a and cytochrome c oxidase subunit II, and attenuated the cytotoxic response to TNF-alpha, indicating a direct link between these two phenomena.

Porphyria cutanea tarda as a Predictor of Poor Response to Interferon Alfa Therapy in Chronic Hepatitis C

BACKGROUND

Porphyria cutanea tarda (PCT) is sometimes associated with hepatitis C virus chronic infection. The aim of this study was to describe the effect of interferon alfa (IFN-a) in the treatment of patients with chronic hepatitis C and PCT.

METHODS

We treated a total of 66 patients with chronic hepatitis C with IFN-a 2b (5 MU t.i.w.) for 12 months. Twenty-two of these patients suffered from PCT as well. These patients differed from patients without PCT in that they were men, past history of alcohol abuse and HFE gene mutations were more common and the source of infection was almost always unknown.

RESULTS

Sustained virologie response was obtained in 19.7% of the 66 treated patients, 27.3% in the non-PCT group and 4.5% in the PCT group (P < 0.05). This difference could not be ascribed to the difference in sex of patients, history of alcohol abuse, HCV genotype or iron status.

CONCLUSION

Multivariate logistic regression analysis revealed that PCT is independently and significantly associated with non-sustained response to IFNa therapy. In conclusion, patients with chronic hepatitis C and PCT rarely responded to IFNa treatment.

A pilot study of beta-interferon for treatment of patients with chronic hepatitis B who failed to respond to alpha-interferon

BACKGROUND/AIMS

Alpha-interferon achieves persistent loss of hepatitis B virus (HBV) in about 30-40% of patients with chronic hepatitis B. In non-responder patients, the disease may progress leading to complications such as cirrhosis and hepatocellular carcinoma. The aim of the current study was to evaluate the efficacy of beta-interferon in patients with chronic hepatitis B who did not respond to one course of alpha-interferon.

METHODS

Twenty nine alpha-interferon-non-responder patients with chronic hepatitis B (11 hepatitis B e antigen, HBeAg-positive; 18 HBeAg-negative) were treated with 6 million units beta-interferon five times a week for 24 weeks. The post-treatment follow-up lasted for 48 weeks.

RESULTS

At the end of treatment, 38% of patients (18% HBeAg-positive; 50% HBeAg-negative) had normal serum aminotransferase levels and negative serum HBV DNA. At the end of follow-up, HBV DNA was no longer detectable in serum in 21% of patients (18% HBeAg-positive; 22% HBeAg-negative). Beta-interferon was well tolerated and safe.

CONCLUSIONS

This pilot study suggests that beta-interferon therapy is effective and safe in the retreatment of patients with chronic hepatitis B who had not responded to a previous alpha-interferon cycle.

Autoimmune enteropathy in an adult with autoimmune multisystemic involvement

We describe the case of a 58-year-old woman with autoimmune enteropathy associated with thyroiditis, gastritis, transitory neutropenia, sicca syndrome and severe axonal polyneuropathy of autoimmune origin. Enterocyte autoantibodies were not detected. However, predisposition to autoimmune disease was indicated by the presence of high titres of anti-gastric parietal cell, anti-thyroglobulin, anti-thyroid peroxidase and anti-neutrophil antibodies. CD4+ and CD8+ lymphocytes were equally distributed in the lamina propria of the small intestine, but CD8+ cells were highly represented among intraepithelial lymphocytes.

Sp1 and Sp3 transcription factors mediate malondialdehyde-induced collagen alpha 1(I) gene expression in cultured hepatic stellate cells

Malondialdehyde, the end product of lipid peroxidation, has been shown to stimulate collagen alpha1(I) (Col1a1) gene expression. However, mechanisms of this effect are unclear. The purpose of this study was to clarify these mechanisms. Rat hepatic stellate cells were cultured in the presence of 200 microm malondialdehyde, and the effects on collagen gene expression and the binding of nuclear proteins to the col1a1 promoter were analyzed. Malondialdehyde treatment induced an increase in the cellular levels of col1a1 mRNA that was abrogated by pretreating cells with cycloheximide, p-hydroxymercuribenzoate, pyridoxal 5'-phosphate, and mithramycin. Transient transfections showed that malondialdehyde exerted its effect through regulatory elements located between -220 and -110 bp of the col1a1 promoter. Gel retardation assays demonstrated that malondialdehyde increased the binding of nuclear proteins to two elements located between -161 and -110 bp of the col1a1 promoter. These bindings were supershifted with Sp1 and Sp3 antibodies. Finally, malondialdehyde increased cellular levels of the Sp1 and Sp3 proteins and Sp1 mRNA. Our data indicated that treatment of hepatic stellate cells with malondialdehyde stimulated col1a1 gene expression by inducing the synthesis of Sp1 and Sp3 and their binding to two regulatory elements located between -161 and -110 bp of the col1a1 promoter.

Expression of small heat shock protein alphaB-crystallin is induced after hepatic stellate cell activation

Using the differential PCR display method to select cDNA fragments that are differentially expressed after hepatic stellate cell (HSC) activation, we have isolated from activated HSCs a cDNA that corresponds to rat alphaB-crystallin. Northern blots confirmed expression of alphaB-crystallin in culture-activated HSCs but not in quiescent HSCs. Western blot analysis and immunocytochemical staining confirmed expression of alphaB-crystallin protein in activated but not quiescent HSCs. alphaB-crystallin is induced as early as 6 h after plating HSCs on plastic and continues to be expressed for 14 days in culture. Expression of alphaB-crystallin was also induced in vivo in activated HSCs from experimental cholestatic liver fibrosis. Confocal microscopy demonstrated a cytoplasmic distribution of alphaB-crystallin in a cytoskeletal pattern. Heat shock treatment resulted in an immediate perinuclear redistribution that in time returned to a normal cytoskeletal distribution. The expression pattern of alphaB-crystallin was similar to that of HSP25, another small heat shock protein, but differed from the classic heat shock protein HSP70. Therefore, alphaB-crystallin represents an early marker for HSC activation.

Decreased bone mineral density after therapy with alpha interferon in combination with ribavirin for chronic hepatitis C

BACKGROUND/AIMS

Several thousand patients with chronic hepatitis C have been treated with interferon plus ribavirin. After observing a male patient who developed severe bone loss during this treatment, we studied skeletal status and bone mineral metabolism in patients on therapy with interferon plus ribavirin.

METHODS

Bone mineral density and biochemical bone markers were studied in 32 male patients (31-58 years old) treated for 12 months with either interferon alone (group 1; n=13) or interferon plus ribavirin (group 2; n= 19).

RESULTS

Bone mineral density was significantly lower in group 2 (0.877-0.07 g/cm2) than in group 1 (1.108+/-0.08 g/cm2, p<0.001). Likewise, T- and Z-score values were also decreased in group 2 (T: -1.95+/-0.6. Z: -1.76+/-0.51) compared with group 1 (T: 0.19+/-0.6; p<0.001. Z: 0.26+/-0.6; p<0.001). Serum and urine biochemical bone markers were normal in both groups. However, urinary calcium excretion was decreased in patients on combined therapy.

CONCLUSION

Treatment of chronic hepatitis C with interferon plus ribavirin may induce bone loss. This secondary effect should be investigated during the follow-up of these patients, since they may require therapies aimed at prevention or amelioration of these defects.

Collagen alpha1(I) gene contains an element responsive to tumor necrosis factor-alpha located in the 5' untranslated region of its first exon

The aims of the present study were to identify the cis-acting element through which tumor necrosis factor-alpha (TNFalpha) inhibits collagen alpha1(I) gene transcription and the trans-acting factors involved in this effect in cultured hepatic stellate cells. Deletion analysis of the collagen alpha1(I) promoter demonstrated that TNFalpha inhibited gene expression through an element located between -59 and + 116 bp relative to the transcription start site. DNase I protection assays revealed a footprint between +68 and +86 bp of the collagen first exon, the intensity of which decreased when the DNA probe was incubated with nuclear protein from TNFalpha-treated hepatic stellate cells. This footprint contained a G+C-rich box. Transfection experiments demonstrated that mutations in this G+C-rich element abrogated the inhibitory effect of TNFalpha on the collagen alpha1(I) promoter. Gel retardation experiments using a radiolabeled oligonucleotide containing sequences of this region confirmed that TNFalpha treatment decreased the formation of two complexes between nuclear proteins and DNA. These complexes were efficiently blocked with an oligonucleotide containing an Spl-binding site and were supershifted with specific Spl and Sp3 antibodies. These results suggest that TNFalpha inhibits collagen alpha1(I) gene expression by decreasing the binding of Spl to a G+C-rich box in the 5' untranslated region of its first exon.

Sp family of transcription factors is involved in iron-induced collagen alpha1(I) gene expression

The purpose of this study was to identify the cis-acting elements and the trans-acting factors involved in the iron-induced expression of the collagen alpha1(I) (COL1aI) gene. Rat hepatic stellate cells were cultured in the presence of 50 microM ferric chloride, 50 microM ascorbic acid, and 250 microM citric acid (Fe/AA/CA), and the effects on collagen gene expression and the binding of nuclear proteins to the COL1aI promoter were measured. The Fe/AA/CA treatment induced a time- and dose-dependent increase in the cellular levels of COL1aI mRNA that was abrogate by pretreating cells with cycloheximide, antioxidants, and inhibitors of aldehyde-protein adduct formation. Transient transfection experiments showed that Fe/AA/CA exerted its effect through regulatory elements located between -220 and -110 bp of the COL1aI promoter. Gel retardation assays showed that Fe/AA/CA increased the binding of nuclear proteins to two elements located between -161 and -110 bp of the COL1aI promoter. These bindings were blocked by unlabeled consensus Sp1 oligonucleotide and supershifted with Sp1 and Sp3 antibodies. Finally, Fe/AA/CA increased cellular levels of the Sp1 and Sp3 proteins and Sp1 mRNA. Treatment with Fe/AA/CA stimulates COL1aI gene expression by inducing the synthesis of Sp1 and Sp3 and their binding to two regulatory elements located between -161 and -110 bp of the COL1aI promoter.

Interleukin-6 increases rat metalloproteinase-13 gene expression through stimulation of activator protein 1 transcription factor in cultured fibroblasts

The role of IL-6 in collagen production and tissue remodeling is controversial. In Rat-1 fibroblasts, we measured the effect of IL-6 on matrix metalloproteinase-13 (MMP-13), c-jun, junB, and c-fos gene expression, binding of activator protein 1 (AP1) to DNA, amount of AP1 proteins, immunoreactive MMP-13 and TIMP-1 proteins, and Jun N-terminal kinase activity. We show that IL-6 increased MMP-13-mRNA and MMP-13 protein. These effects were exerted by acting on the AP1-binding site of the MMP-13 promoter, as shown by transfecting cells with reporter plasmids containing mutations in this element. Mobility shift assays demonstrated that IL-6 induced the DNA binding activity of AP1. This effect was accompanied by a marked increase in c-Jun, JunB, and c-Fos mRNA, as well as in c-Jun protein and its phosphorylated form. The latter is not due to increased Jun N-terminal kinase activity but to a decreased serine/threonine phosphatase activity. We conclude that IL-6 increases interstitial MMP-13 gene expression at the promoter level. This effect seems to be mediated by the induction of c-jun, junB, and c-fos gene expression, by the binding of AP1 to DNA, by increasing phosphorylated c-Jun, and by the inhibition of serine/threonine phosphatase activity. These effects of IL-6 might contribute to remodeling connective tissue.

NF-kappaB inhibits expression of the alpha1(I) collagen gene

Fibrosis results from an increase in the synthesis and deposition of type I collagen. Fibrosis is frequently associated with inflammation, which is accompanied by increased levels of tumor necrosis factor-alpha (TNFalpha) and activation of the transcription factor NF-kappaB. However, several agents known to activate NF-kappaB, such as phorbol 12-myristate 13-acetate (PMA) and TNFalpha, result in decreased expression of type I collagen. Therefore, we directly examined the effects of NF-kappaB on alpha1(I) collagen gene expression in two collagen-producing cells, NIH 3T3 fibroblasts and hepatic stellate cells (HSCs). Transient transfections of NIH 3T3 cells or HSCs using NF-kappaB p50, p65, and c-Rel expression plasmids with collagen reporter gene plasmids demonstrated a strong inhibitory effect on transcription of the collagen gene promoter. Dose-response curves showed that p65 was a stronger inhibitor of collagen gene expression than was NF-kappaB p50 or c-Rel (maximum inhibition 90%). Transient transfections with reporter gene plasmids containing one or two Spl binding sites demonstrated similar inhibitory effects of NF-kappaB p65 on the activity of these reporter genes, suggesting that the inhibitory effects of NF-kappaB p65 are mediated through the critical Spl binding sites in the alpha1(I) collagen gene promoter. Cotransfection experiments using either a super-repressor I[ke]B or Spl partially blocked the inhibitory effects of p65 on collagen reporter gene activity. Coimmunoprecipitation experiments demonstrated that NF-kappaB and Spl do interact in vivo. Nuclear run-on assays showed that NF-kappaB p65 inhibited transcription of the endogenous alpha1(I) collagen gene. Together, these results demonstrate that NF-kappaB decreases transcription of the alpha1(I) collagen gene.

Collagenous gastrobulbitis and collagenous colitis. Case report and review of the literature

A case is reported of collagenous gastrobulbitis on collagenous colitis in a 57-year-old woman with a 6-month history of watery diarrhea. Low serum levels of total proteins and albumin and increased fecal elimination of alpha1-antitrypsin were the only abnormal laboratory test results. Biopsy specimens from the colon, rectum, antrum, fundus, and duodenal bulb showed a thick subepithelial band composed of ultrastructurally normal collagen immunohistochemically negative for collagen IV and laminin. The diarrhea resolved with prednisone and responded to this treatment after a relapse 6 months later. One year later the patient developed severe alimentary intolerance and secondary weight loss. This symptom also responded to the same treatment. However, the collagen deposition did not disappear in the second biopsy samples of colonic and gastric mucosa. Only six cases have been previously reported with gastric and/or duodenal subepithelial collagenous deposition. Four were associated with collagenous colitis. One of these presented a subepithelial collagenous band in the terminal ileum. All these features suggest that this collagen deposition may affect the entire digestive tract with variable intensity, extension, and symptoms.