Long-term interferon-alpha treatment of children with chronic hepatitis delta: a multicentre study

We assessed the efficacy of prolonged interferon-alpha (IFN) therapy in children with chronic hepatitis caused by hepatitis delta virus (HDV) by treating 26 paediatric cases with IFN-alpha 2b (5 MU m-2, then 3 MU m-2 three times weekly for 12 (medium-term group MTG) or 24 months (long-term group, LTG). Compliance and tolerability were acceptable. At the end of therapy a complete biochemical response [normalization of alanine aminotransferase (ALT)] occurred in 12 children (5/13 in MTG and 7/13 in LTG). A relapse occurred after stopping IFN in 10 cases (five in MTG and five in LTG). Two patients from the LTG had normal liver function tests during 12 months of follow-up. Six of the eight hepatitis B e antigen (HBeAg) positive children lost HBeAg, while all six hepatitis B virus (HBV) DNA positive patients lost HBV DNA during treatment. HBeAg reappeared later in two children. HDV RNA, present in 10/10 cases of MTG before treatment, persisted after 12 months IFN therapy in 3/10. One year after stopping therapy, 8/10 patients were again HDV RNA positive. Two children cleared hepatitis delta antigen (HDVAg) from the liver. No significant improvements in liver histology were seen in both groups. Our experience suggests that IFN-alpha treatment in children with chronic type D hepatitis has a transient effect, and long-term treatment does not appear to induce a greater therapeutic benefit in terms of biochemical and virological response.

A multicenter randomized controlled trial of recombinant interferon-alpha 2b in patients with acute transfusion-associated hepatitis C

To assess whether interferon-alpha might prevent non-A, non-B hepatitis from becoming chronic, 45 consecutive patients with transfusion-associated hepatitis were enrolled in a randomized clinical trial. Thirty-eight patients had hepatitis C virus infection, and 7 had non-A, non-B, non-C hepatitis. Twenty-six patients (22 with HCV) were given 3 MU of recombinant interferon-alpha 2b three times a week for 12 wk, whereas 19 (16 with HCV) were not. Biochemical and virological parameters were monitored at regular intervals during an 18-mo follow-up. At the end of the 3-mo therapy, 16 (73%) patients with hepatitis C had normal serum ALT activity, compared with 7 (44%) who were not treated (NS). Fifty-three percent of the treated patients and none of the untreated patients had normal ALT levels and no HCV RNA (p = 0.0087). At the end of the 18-mo follow-up, 13 (59%) treated patients had normal ALT levels, compared with 6 (37%) untreated controls (NS). Thirty-nine percent had normal ALT and no HCV RNA, compared with none of the controls (p = 0.035). Four patients (22%) had had sustained complete responses to interferon, defined as normal ALT levels and no HCV RNA at the end of the 3-mo treatment period and the 18-mo follow-up period. All seven patients with non-A, non-B, non-C hepatitis, treated and untreated, recovered uneventfully from hepatitis.(ABSTRACT TRUNCATED AT 250 WORDS)

DNA methylation of coding and non-coding regions of the human H-RAS gene in normal and tumor tissues

To study a possible role of DNA methylation in the regulation of expression of the human H-RAS gene in vivo, 41 samples of different normal tissues and 33 tumors of various histotypes were analysed for DNA methylation. In a subset of normal tissues the RNA expression was also examined. The promoter region of the gene showed the features of a CpG island being CpG rich and unmethylated in all the normal tissues and tumors. The coding region displayed an intermediate level of methylation in the majority of normal and tumor tissues. Among the normal tissues only thymus DNA was found to be hypermethylated, while testes and sperm cells DNAs were hypomethylated. The 3' region was found to be completely methylated only in sperm cells and was never completely demethylated. The majority of the tissues showed an intermediate level of methylation, and a certain tissue specificity emerged by comparing tissues of the same and different histotypes. However, the overall methylation of both coding and 3' regions did not correlate with the levels of tissue-specific RNA expression. In heterozygous individuals, allelic methylation of the 3' region showed either perfectly balanced or slightly unbalanced methylation of the two alleles in normal tissues, while an allele-specific methylation was found in 5 out of 12 fresh tumor samples.

Flow cytometric detection of the mitochondrial BCL-2 protein in normal and neoplastic human lymphoid cells

The bcl-2 proto-oncogene, rearranged and deregulated in B-cell lymphomas bearing the t(14;18) translocation, encodes an inner mitochondrial membrane protein that blocks apoptotic cell death. We have developed a sensitive immunofluorescence assay for the single- and multicolor flow cytometric analysis of bcl-2 protein in relation to other markers and cell cycle, based on a fixation-permeation step of cells with paraformaldehyde and Triton X100 and the use of a bcl-2 specific monoclonal antibody (MoAb). As an application of this method, we have examined the expression of bcl-2 in normal and neoplastic lymphoid cells. We have found that greater than 80% of normal T-and B-cells are bcl-2 positive; following in vitro mitogen activation, the bcl-2 reactivity decreased slightly in the former but markedly in latter cells. In both cases the bcl-2 expression was not restricted to a specific phase of the cell cycle, as evidenced by two-color analysis. On lymphoblastoid cell lines, the bcl-2 staining intensity was variable and not necessarily correlated to molecular rearrangements of the bcl-2 gene. Among fresh B-cell non-Hodgkin's lymphomas (B-NHL), most sporadic Burkitt's cases were bcl-2 negative. Of four centroblastic-centrocytic cases with rearrangements of the bcl-2 gene, only two presented elevated amounts of bcl-2 protein, indicating that the levels of bcl-2 are not diagnostic of the translocation.(ABSTRACT TRUNCATED AT 250 WORDS)

Clonal immunoglobulin gene rearrangements and normal T-cell receptor, bcl-2, and c-myc genes in primary cutaneous B-cell lymphomas

Fourteen cases of primary cutaneous B-cell lymphomas were investigated at the immunohistochemical and molecular level to further characterize this newly defined entity. Neoplastic cells from all cases, phenotyped with a panel of monoclonal antibodies, were positive for HLA-DR, for the B-cell markers CD19, CD22, but not CD23 (except one case), and negative for the T-cell marker CD2. Monoclonal immunoglobulin light chains were demonstrated in six cases. The reactivity with the Ki-67 monoclonal antibody indicated that the neoplastic cells are proliferating. In five biopsies the presence of dendritic cells infiltrating the neoplastic areas was revealed using the monoclonal antibody Kim4b. By Southern blot analysis, clonal rearrangement of the immunoglobulin heavy chain gene (involving one or both alleles) was shown in 12 of 14 cases and of the light chain genes in 13 cases. The bcl-2 oncogene, normally involved in nodal follicular lymphomas, was in germ-line configuration. The c-myc and the beta and gamma chain genes of the T-cell receptor were also in the germ-line configuration. None of the cases presented Epstein-Barr virus sequences. These data indicate that primary cutaneous lymphomas of B-cell origin share morphological and phenotypic similarities with the nodal B-cell lymphomas of follicular histotype, are proliferating, and express in 45% of cases clear monoclonal immunoglobulin light chain; the molecular analysis confirms the B-cell derivation and the monoclonal nature of this neoplasia; it also shows that neither bcl-2 nor c-myc oncogenes are involved and that no inappropriate rearrangements of the T-cell receptor genes are found in this lymphoma.

Detection of bone marrow minimal disease in non-Hodgkin's lymphoma patients by gene rearrangement analysis

Bone marrow aspirates from 13 patients with non-Hodgkin's lymphoma of B- and T-lineage were drawn during staging procedures and examined by a combined technique involving immune selection and gene rearrangement analysis with DNA probes specific for the heavy-chain immunoglobulin gene (JH) or T cell receptor gene (T beta and T gamma). Morphologic examination of bone marrow biopsies revealed involvement by lymphoma in one case and suspicious accumulation of blasts in another. Southern blot analysis of the samples showed the presence of a rearranged clonal band in two samples, including the morphologically involved marrow. Clonal rearrangements were not detected in the suspected marrow. Bone marrow relapses were not observed in any of these patients after a median follow-up of 20 months. Antigen receptor rearrangements are tumor-specific markers which may increase the sensitivity and the specificity of morphologic examination, and may be useful in the proper staging and follow-up of lymphoma patients.

Mixed-lineage leukemias and phenotypic shifts occurring in relapsed cases of acute T lymphoblastic lymphomas

Specimens from 19 patients with NHL were also phenotyped at the onset of the disease; among them, 9 were studied in the relapse phase. The analysis was carried out with monoclonal antibodies directed against T and myeloid cells; at diagnosis, all cases presented an immature thymic phenotype. When analyzed at relapse, phenotypic changes were observed: intra-lineage dedifferentiations (6 cases); mixed-lineage lymphoid and myeloid (2 cases), and pure myeloid relapses (1 case). The molecular analysis of the TCR-genes configuration showed a germ-line pattern at onset and relapse in Case 9 and a modification of the rearrangement patterns during the evolution of the disease in Case 6. These data point out that the relapse is often accompanied by intra-lineage modifications resembling dedifferentiation and, more rarely by a myeloid switch. The phenotypic follow-up of these patients may be important to the implementation of chemotherapeutic protocols that are more adequate for the biological evolution of the disease.

Inhibition of DNA restriction enzyme digestion by anthracyclines

The inhibition of restriction enzyme digestion of lambda phage DNA by anthracyclines (i.e., adriamycin, daunomycin, epirubicin, idarubicin and esorubicin) commonly used in the treatment of human leukemia and cancer has been studied in vitro. The anthracyclines used inhibit DNA digestion by SmaI, AvaII, HaeIII, HhaI and HpaII, which cut DNA at guanine-cytosine (G-C) sequence sites, and by EcoRI, which cut DNA at adenine adenine-thymine thymine (AATT) sequence sites. Adriamycin completely inhibits DNA restriction by the indicated enzymes, daunomycin, epirubicin and idarubicin determine only a partial inhibition, while esorubicin does not inhibit DNA restriction at all. An attempt is made to correlate the extent of the in vitro interaction between anthracyclines and DNA to in vivo cardiotoxicity.

Translocation of oncogene c-sis from chromosome 22 to chromosome 17 in a human myelogenous leukemia cell line

By combining somatic cell genetics, in situ hybridization and Southern hybridization, we found that the c-sis oncogene in the human myelogenous leukemia cell line ML3 is translocated from the long arm (q11----qter) of chromosome 22 to the long arm (mid-portion or q21 region) of chromosome 17. This translocation does not result in rearrangement of the c-sis oncogene.