23 research outputs found
Clofarabine and high-dose cytosine arabinoside in the treatment of refractory or relapsed acute myeloid leukaemia
Clofarabine (40Β mg/m2/dayβΓβ5) and high-dose cytosine arabinoside (Ara-C, 1β2Β g/m2/dayβΓβ5) were used in 10 men and 11 women, at a median age of 45 (22β62)βyears, with refractory (Nβ=β4) and relapsed (Nβ=β17) acute myeloid leukaemia, after a median of 3 (2β5) prior regimens. Grade 4 myelosuppression was observed in all cases, with two patients dying of bacterial sepsis. Nine patients achieved a complete remission. Disease status, number of prior therapies, and cytogenetic aberrations were not associated with the outcome. However, remission was only achieved with Ara-C at 2Β g/m2/day and not 1Β g/m2/day (9/15 versus 0/4, Pβ=β0.03)
Carboxyl-terminal truncated HBx regulates a distinct microRNA transcription program in Hepatocellular carcinoma development
Background: The biological pathways and functional properties by which misexpressed microRNAs (miRNAs) contribute to liver carcinogenesis have been intensively investigated. However, little is known about the upstream mechanisms that deregulate miRNA expressions in this process. In hepatocellular carcinoma (HCC), hepatitis B virus (HBV) X protein (HBx), a transcriptional trans-activator, is frequently expressed in truncated form without carboxyl-terminus but its role in miRNA expression and HCC development is unclear. Methods: Human non-tumorigenic hepatocytes were infected with lentivirus-expressing full-length and carboxyl-terminal truncated HBx (Ct-HBx) for cell growth assay and miRNA profiling. Chromatin immunoprecipitation microarray was performed to identify the miRNA promoters directly associated with HBx. Direct transcriptional control was verified by luciferase reporter assay. The differential miRNA expressions were further validated in a cohort of HBV-associated HCC tissues using real-time PCR. Results: Hepatocytes expressing Ct-HBx grew significantly faster than the full-length HBx counterparts. Ct-HBx decreased while full-length HBx increased the expression of a set of miRNAs with growth-suppressive functions. Interestingly, Ct-HBx bound to and inhibited the transcriptional activity of some of these miRNA promoters. Notably, some of the examined repressed-miRNAs (miR-26a, -29c, -146a and -190) were also significantly down-regulated in a subset of HCC tissues with carboxyl-terminal HBx truncation compared to their matching non-tumor tissues, highlighting the clinical relevance of our data. Conclusion: Our results suggest that Ct-HBx directly regulates miRNA transcription and in turn promotes hepatocellular proliferation, thus revealing a viral contribution of miRNA deregulation during hepatocarcinogenesis. Β© 2011 Yip et al.published_or_final_versio
Marginal zone B-cell lymphoma mimicking extramedullary plasmacytoma and the clinical outcome after treatment
Marrow tuberculosis without granuloma formation in a patient with human immunodeficiency virus infection
A novel zebrafish jak2a V581F model shared features of human JAK2 V617F polycythemia vera
Objective : The Janus kinase 2 (JAK2) is important for embryonic primitive hematopoiesis. A gain-of-function JAK2 (JAK2V617F) mutation in human is pathogenetically linked to polycythemia vera (PV). In this study, we generated a zebrafish ortholog of human JAK2V617F (referred herewith jak2aV581F) by site-directed mutagenesis and examined its relevance as a model of human PV.Materials and Methods : Zebrafish embryos at one-cell stage were injected with jak2aV581F mRNA (200pg/embryo). In some experiments, the embryos were treated with a specific JAK2 inhibitor, TG101209. The effects of jak2a stimulation on hematopoiesis, jak/stat signaling, and erythropoietin signaling were evaluated at 18-somites.Results : Injection with jak2aV581F mRNA significantly increased erythropoiesis, as enumerated by flow cytometry based on gfp+ population in dissociated Tg(gata1:gfp) embryos. The response was reduced by stat5.1 morpholino coinjection (control: 4.37% ± 0.08%; jak2aV581F injected: 5.71% ± 0.07%, coinjecting jak2aV581F mRNA and stat5.1 morpholino: 4.66% ± 0.13%; p < 0.01). jak2aV581F mRNA also upregulated gata1 (1.83 ± 0.08 fold; p = 0.005), embryonic α-hemoglobin (1.61 ± 0.12 fold; p = 0.049), and β-hemoglobin gene expression (1.65 ± 0.13–fold; p = 0.026) and increased stat5 phosphorylation. These responses were also ameliorated by stat5.1 morpholino coinjection or treatment with a specific JAK2 inhibitor, TG101209. jak2aV581F mRNA significantly reduced erythropoietin gene (0.24 ± 0.03 fold; p = 0.006) and protein expression (control: 0.633 ± 0.11; jak2aV581F mRNA: 0.222 ± 0.07 mIU/mL; p = 0.019).Conclusion : The zebrafish jak2aV581F model shared many features with human PV and might provide us with mechanistic insights of this disease.<br /
A rare variant of transthyretin-related amyloidosis associated with exclusive cardiomyopathy in a Hong Kong Chinese patient
PB2674: CLINICAL, NEUROIMAGING, AND BEHAVIORAL RISK FACTORS FOR NEUROCOGNITIVE IMPAIRMENT IN CHINESE PATIENTS WITH HEMOPHILIA: A MULTICENTER STUDY
Baveno VII criteria for recompensation predict transplant-free survival in patients with hepatitis B-related decompensated cirrhosis
Background & Aims: The latest Baveno VII consensus has provided guidance for identifying patients who have truly recompensated from those with hepatic decompensation. This study aimed to evaluate patientsβ transplant-free survival in three different stages of cirrhosis. Methods: All patients with chronic HBV infection and liver cirrhosis treated with oral nucleos(t)ide analogues from March 2006 to December 2022 were identified from a territory-wide database in Hong Kong. Patients with follow-up duration of <1 year were excluded. Participants were classified into three mutually exclusive groups: (1) no decompensated events (i.e. compensated group); (2) decompensated events occurred (i.e. decompensated group); or (3) decompensated events occurred followed by recompensation according to Baveno VII criteria (i.e. recompensated group). A time-dependent Cox proportional hazard model was adopted for evaluation. The follow-up period was 5 years. Results: A total of 4,701 patients with cirrhosis and HBV who were treated with entecavir, tenofovir disoproxil fumarate (TDF), and tenofovir alafenamide fumarate (TAF) were identified. During a median follow-up of 5 years (interquartile range 3.7, 5 years), 3,327 (70.8%), 1,347 (29.2%), and 265 (5.6%) patients had compensated, decompensated, and recompensated cirrhosis, respectively, at least once before the end of the study. In the time-dependent multivariable model, the recompensated groupΒ had similar transplant-free survival compared with the compensated group (adjusted hazard ratio 1.16; 95% CI 0.72β1.86; pΒ = 0.536). The 5-year transplant-free survival rate was 89.3% for the compensated group, whereas it was 76.0% for the recompensated group, reflecting a minimal difference between the two groups. Conclusions: The clinical significance of recompensation of cirrhosis in improving patient outcomes for individuals with CHB infection was highlighted in this study. Early identification and treatment with nucleos(t)ide analogues might promote hepatic recompensation and thus reduce mortality in patients with CHB. Impact and implications: The latest Baveno VII consensus introduces the new concept of hepatic recompensation, which refers to the reversal of the structural and functional changes of cirrhosis after removal, cure, or suppression of the aetiologyΒ of cirrhosis. It is essential to investigate the transplant-free survival rates of patients who are able to achieve hepatic recompensation, as this has significant implications for the medical resources required to manage liver failure and transplantation. This study features the clinical significance of hepatic recompensation by comparing patient outcomes of those who achieve it to those who do not. The early identification and use of antiviral treatment with nucleos(t)ide analogues is a pivotal strategy to promote hepatic recompensation, which has the potential to significantly reduce mortality rates in patients with chronic HBV infection and ultimately aid in the elimination of hepatitis
2009
ARTICLES 913 Acute Myeloid Leukemia Introduction The NPM1 gene is frequently altered in hematologic malignancies. 2 NPM1-mutated AML has distinctive clinicopathological and molecular features. Most notably, the mutation is closely associated with normal karyotype and relatively favorable prognosis in the absence of FLT3-internal tandem duplication (ITD). 3 While genotyping the NPM1 mutations, a polymorphic nucleotide T deletion (delT) at position 1,146 of the NPM1 3'-untranslated region (UTR) was reported in 60%-70% of AML patients. 6,7 Here, we revealed that the homozygous state of the NPM1 delT polymorphism had important clinical and biological implications in AML involving an illegitimate microRNA (miRNA) regulation. Design and Methods Patients We analyzed 149 adult and 70 childhood patients with de novo AML; therapy-related AML or AML arising from a prior myelodysplastic syndrome were excluded. Patients' characteristics are shown in Online Supplementary Table S1. All patients gave informed consent for the study, which was approved by the Joint CUHK-NTEC Clinical Research Ethics Committee and was conducted in accordance with the Declaration of Helsinki. Patients with acute promyelocytic leukemia (APL) were excluded for survival analysis. Overall, complete survival data were available from 93 adult and 61 childhood patients with non-APL who had received treatment. All the 93 adult patients were treated with the standard cytarabine plus daunorubicin '7+3' induction chemotherapy regimen. Normal bone marrow (BM) and peripheral blood samples were obtained from healthy donors who had no prior history of malignancy. Cell culture Cell lines were cultured in RPMI-1640 medium containing 10% fetal bovine serum. Nucleophosmin, encoded by NPM1, is a haploinsufficient suppressor in hematologic malignancies. NPM1 mutations are mostly found in acute myeloid leukemia patients with normal karyotype and associated with favorable prognosis. A polymorphic nucleotide T deletion with unknown significance is present in the NPM1 3'-untranslated region. Here, we showed that the homozygous nucleotide T deletion was associated with adverse outcomes and could independently predict shortened survival in patients with de novo acute myeloid leukemia. Mechanistically, we demonstrated that the nucleotide T deletion created an illegitimate binding NPM1 for miR-337-5p, which was widely expressed in different acute myeloid leukemia subtypes and inhibited NPM1 expression. Accordingly, NPM1 levels were found to be significantly reduced and correlated with miR-337-5p levels in patients carrying a homozygous nucleotide T-deletion genotype. Together, our findings uncover a microRNAmediated control of NPM1 expression that contributes to disease heterogeneity and suggest additional prognostic values of NPM1 in acute myeloid leukemia. A polymorphism in the 3'-untranslated region of the ABSTRACT Cytogenetic and mutational studies Cytogenetics were classified into favorable, intermediate, and adverse according to the UK MRC classification