Rapidly increasing liver progenitor cell numbers in human regenerating liver after portal vein ligation and liver partition.

BACKGROUND: Liver regeneration is dependent on the proliferation of hepatocytes. Hepatic progenitor cells are intra-hepatic precursor cells capable of differentiating into hepatocytes or biliary cells. Although liver progenitor cell proliferation during the regenerative process has been observed in animal models of severe liver injury, it has never been observed in vivo in humans because it is unethical to take multiple biopsy specimens for the purpose of studying the proliferation of liver progenitor cells and the roles they play in liver regeneration. Associating liver partition and portal vein ligation for staged hepatectomy (ALPPS) is a staged procedure for inducing remnant liver hypertrophy so that major hepatectomy can be performed safely. This staged procedure allows for liver biopsy specimens to be taken before and after the liver begins to regenerate. CASE PRESENTATION: The liver progenitor cell proliferation is observed in a patient undergoing ALPPS for a metastatic hepatic tumour. Liver biopsy is acquired before and after ALPPS for the calculation of average number of liver progenitor cell under high magnification examination by stain of immunomarkers. This is the first in vivo evidence of growing liver progenitor cells demonstrated in a regenerating human liver.

Thyroid hormone protects hepatocytes from HBx-induced carcinogenesis by enhancing mitochondrial turnover.

Infection by hepatitis B virus (HBV) accounts for 50-80% of hepatocellular carcinoma (HCC) development worldwide, in which the HBV-encoded X protein (HBx) has critical role in the induction of carcinogenesis. Several studies have shown that thyroid hormone (TH) suppresses HCC development and protects hepatocytes from HBx-induced damage, thus it is of interest to examine whether TH can protect hepatocytes from HBx-induced carcinogenesis. By treating HBx- transgenic mice with or without TH, we confirmed the protective effects of TH on HBx-induced hepatocarcinogenesis, which was achieved via reduction of reactive oxygen species (ROS) inflicted DNA damage. We further found that TH induced biogenesis of mitochondria (MITO) and autophagy of HBx-targeted MITO simultaneously, consequently leading to suppression of HBx-promoted ROS and carcinogenesis. Using microarray data analysis, this protective effect of TH was found to be mediated via activation of PTEN-induced kinase 1 (PINK1) in hepatocytes. PINK1, in turn, activated and recruited Parkin, an E3 ligase, to ubiquitinate MITO-associated HBx protein and trigger selective mitophagy. The pathological significance of the TH/PINK1 pathway in liver protection was confirmed by the concomitant decrease in expression of both TR and PINK1 in matched HCC tumor tissues and negatively correlated with aggressive progression of cancer and poor prognosis. Our data indicate that TH/PINK1/Parkin pathway has a critical role in protecting hepatocytes from HBx-induced carcinogenesis. Notably, several liver-targeting therapeutic derivatives of TH facilitating prevention or therapy of steatosis have been identified. Furthermore, our proof-of-concept experiments suggest that application of T3 constitutes an effective novel therapeutic or preventive option for HCC. Thus, the utilization of the agonists of TRs could be the meaningful strategy in liver relative diseases, ranging from simple hepatic steatosis to HCC.

Inhibitive effects of mulberry leaf-related extracts on cell adhesion and inflammatory response in human aortic endothelial cells.

Effects of mulberry leaf-related extracts (MLREs) on hydrogen peroxide-induced DNA damage in human lymphocytes and on inflammatory signaling pathways in human aortic endothelial cells (HAECs) were studied. The tested MLREs were rich in flavonols, especially bombyx faces tea (BT) in quercetin and kaempferol. Polyphenols, flavonoids, and anthocyanidin also abounded in BT. The best trolox equivalent antioxidant capacity (TEAC) was generated from the acidic methanolic extracts of BT. Acidic methanolic and water extracts of mulberry leaf tea (MT), mulberry leaf (M), and BT significantly inhibited DNA oxidative damage to lymphocytes based on the comet assay as compared to the H2O2-treated group. TNF- α -induced monocyte-endothelial cell adhesion was significantly suppressed by MLREs. Additionally, nuclear factor kappa B (NF- κ B) expression was significantly reduced by BT and MT. Significant reductions were also observed in both NF- κ B and activator protein (AP)-1 DNA binding by MLREs. Significant increases in peroxisome proliferator-activated receptor (PPAR) α and γ DNA binding by MLREs were also detected in M and MT extracts, but no evidence for PPAR α DNA binding in 50 µ g/mL MT extract was found. Apparently, MLREs can provide distinct cytoprotective mechanisms that may contribute to its putative beneficial effects on suppressing endothelial responses to cytokines during inflammation.

Thyroid hormone receptor represses miR-17 expression to enhance tumor metastasis in human hepatoma cells.

MicroRNAs (miRNAs) are thought to control tumor metastasis through direct interactions with target genes. Thyroid hormone (T3) and its receptor (TR) are involved in cell growth and cancer progression. However, the issue of whether miRNAs participate in T3/TR-mediated tumor migration is yet to be established. In the current study, we demonstrated that T3/TR negatively regulates mature miR-17 transcript expression, both in vitro and in vivo. Luciferase reporter and chromatin immunoprecipitation (ChIP) assays localized the regions responding to TR-mediated repression to positions -2234/-2000 of the miR-17 promoter sequence. Overexpression of miR-17 markedly inhibited cell migration and invasion in vitro and in vivo, mediated via suppression of matrix metalloproteinases (MMP)-3. Moreover, p-AKT expression was increased in miR-17-knockdown cells that led to enhanced cell invasion, which was blocked by LY294002. Notably, low miR-17 expression was evident in highly metastatic cells. The cell migration ability was increased by T3, but partially reduced upon miR-17 overexpression. Notably, TRα1 was frequently upregulated in hepatocellular carcinoma (HCC) samples and associated with low overall survival (P=0.023). miR-17 expression was significantly negatively associated with TRα1 (P=0.033) and MMP3 (P=0.043) in HCC specimens. Data from our study suggest that T3/TR, miR-17, p-AKT and MMP3 activities are interlinked in the regulation of cancer cell metastasis.

Cardiac iron measurement and iron chelation therapy in patients with ß thalassaemia major: experience from Taiwan.

BACKGROUND: The aims of our study were to evaluate (i) the relationship between cardiac T2* values and cardiac complications in Asian ß-thalassaemia major (TM) patients, and (ii) the association between cardiac T2* values and other parameters currently used to predict cardiac complications as a result of transfusion iron overload. METHODS: We examined the myocardial iron loads of 88 TM patients from Taiwan with cardiac T2* magnetic resonance imaging (MRI) and assessed the correlation between cardiac T2* values and serum ferritin levels, liver iron concentration and left ventricular ejection fraction (LVEF). We also determined the predictive value of these measurements for the development of arrhythmia. RESULTS AND CONCLUSION: In our group of Taiwanese patients, the relative risk for arrhythmia was 10·36 when cardiac T2* values were less than 10 ms (compared with ≥10 ms) and 1·98 when serum ferritin levels increased >2500 ng mL(-1) (compared with ≤2500 ng mL(-1) ). Serum ferritin levels correlated with cardiac T2* values in patients with abnormal myocardial iron loads (T2* < 20 ms, r = -0·48, P = 0·004, n = 34), but LVEF (measured by echocardiography) gave no indication of excess myocardial iron deposition (r = -0·07, P = 0·52) or of the risk of developing arrhythmia.

Thyroid hormone suppresses cell proliferation through endoglin-mediated promotion of p21 stability.

Hypothyroidism has been associated with significantly elevated risk for hepatocellular carcinoma (HCC), although the precise underlying mechanisms remain unknown at present. Thyroid hormone (T3) and its receptor (TR) are involved in metabolism and growth. Endoglin is a T3/TR candidate target gene identified from our previous studies. Here, we demonstrated that T3 positively regulates endoglin mRNA and protein levels, both in vitro and in vivo. The thyroid hormone response elements of endoglin were identified at positions -2114/-2004 and -2032/-1973 of the promoter region using the electrophoretic mobility shift assay and chromatin immunoprecipitation assay. Endoglin was downregulated in the subgroups of HCC patients and significantly associated with histology grade (negative association, P=0.001), and this expression level was significantly associated with TRα1 in these HCC patients. Our results clearly indicate that p21 is involved in T3-mediated suppression of cell proliferation. Knock down of endoglin expression in HCC cells facilitated p21 polyubiquitination and promoted cell proliferation in the presence of T3. The data collectively suggest that T3/TR signaling suppresses cell proliferation by upregulating endoglin, in turn, affecting p21 stability. The results indicate that endoglin has a suppressor role to inhibit cell proliferation in HCC cell lines.

PPARγ regulates the mitochondrial dysfunction in human neural stem cells with tumor necrosis factor alpha.

Peroxisome proliferator-activated receptor gamma (PPARγ) belongs to a family of ligand-activated transcription factors, and its ligands are known to control many physiological and pathological conditions. The hypothesis of our study was that the PPARγ agonist (rosiglitazone) could mediate tumor necrosis factor alpha (TNFα) related to the regulation of human neural stem cells (hNSCs), by which TNFα possibly fulfills important roles in neuronal impairment. The results show that PPARγ mediates the cell viability of hNSCs via the downregulation of the activity of caspase 3, indicating that this rescue effect of PPARγ could improve the reduced levels of two mitochondrial regulators, adenosine monophosphate-activated protein kinase (AMPK) and Sirtuin 1 (SIRT1) in the hNSCs with TNFα. The stimulation of mitochondrial function by PPARγ was associated with activation of the PPAR coactivator1 alpha (PGC1α) pathway by up-regulation of oxidative defense and mitochondrial systems. The above protective effects appeared to be exerted by a direct activation of the rosiglitazone, because it protected hNSCs from TNFα-evoked oxidative stress and mitochondrial deficiency. Here we show that the rosiglitazone protects hNSCs against Aß-induced apoptosis and promotes cell survival. These findings extend our understanding of the central role of PPARγ in TNFα-related neuronal impairment, which probably increases risks of neurodegenerative diseases. The anti-inflammatory effects of PPARγ in the hNSCs with TNFα, and the involved mechanisms were also characterized.

Thyroid hormone receptors promote metastasis of human hepatoma cells via regulation of TRAIL.

Although accumulating evidence has confirmed the important roles of thyroid hormone (T(3)) and its receptors (TRs) in tumor progression, the specific functions of TRs in carcinogenesis remain unclear. In the present study, tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) was directly upregulated by T(3) in TR-overexpressing hepatoma cell lines. TRAIL is an apoptotic inducer, but it can nonetheless trigger non-apoptotic signals favoring tumorigenesis in apoptosis-resistant cancer cells. We found that TR-overexpressing hepatoma cells treated with T(3) were apoptosis resistant, even when TRAIL was upregulated. This apoptotic resistance may be attributable to simultaneous upregulation of Bcl-xL by T(3), because (1) knockdown of T(3)-induced Bcl-xL expression suppressed T(3)-mediated protection against apoptosis, and (2) overexpression of Bcl-xL further protected hepatoma cells from TRAIL-induced apoptotic death, consequently leading to TRAIL-promoted metastasis of hepatoma cells. Moreover, T(3)-enhanced metastasis in vivo was repressed by the treatment of TRAIL-blocking antibody. Notably, TRAIL was highly expressed in a subset of hepatocellular carcinoma (HCC) patients, and this high-level expression was significantly correlated with that of TRs in these HCC tissues. Together, our findings provide evidence for the existence of a novel mechanistic link between increased TR and TRAIL levels in HCC. Thus, TRs induce TRAIL expression, and TRAIL thus synthesized acts in concert with simultaneously synthesized Bcl-xL to promote metastasis, but not apoptosis.

Iron overload is associated with low anti-müllerian hormone in women with transfusion-dependent ß-thalassaemia.

OBJECTIVE: To investigate anti-müllerian hormone (AMH) as a best test of ovarian reserve in women with transfusion-dependent ß-thalassaemia, and the relationship between AMH and iron overload. DESIGN AND SETTING: A case-control study in a tertiary medical centre. POPULATION: Twenty-nine women with transfusion-dependent ß-thalassaemia and 29 healthy controls of a similar age were recruited. METHODS: Blood sampling, questionnaires and medical record reviews were used. MAIN OUTCOME MEASURES: The history of iron overload-related morbidities, haematological phenotypes, serum levels of AMH and ferritin, and hormonal profiles were analysed. RESULTS: The serum levels of AMH, luteinising hormone, and estradiol were lower in women with transfusion-dependent ß-thalassaemia than in age-matched normal controls. In women with transfusion-dependent ß-thalassaemia, the serum AMH level was significantly inversely related to the ferritin level, but not related to the presence of hypogonadotrophic hypogonadism, diabetes and haematological phenotypes. The serum ferritin level was positively associated with advanced age and the presence of hypogonadotrophic hypogonadism in the study participants. However, the inverse relationship between AMH and ferritin still exists after further adjustment for advanced age in women with transfusion-dependent ß-thalassaemia. CONCLUSIONS: The present study indicates that the serum AMH levels in women with transfusion-dependent ß-thalassaemia are lower when compared with normal healthy women of a similar age, and are significantly negatively correlated with their serum ferritin levels. This implies that ovarian function might be impaired by the chronic iron overload status in women with transfusion-dependent ß-thalassaemia.

Overexpression of CXCL1 and its receptor CXCR2 promote tumor invasion in gastric cancer.

BACKGROUND: The chemokine (C-X-C motif) ligand 1 (CXCL1) and its receptor CXCR2 are associated with metastasis potential. Our studies were designed to clarify the CXCL1 and CXCR2 expression patterns and to explore their potential role in gastric cancer. DESIGN: The expression of CXCL1 was determined in primary gastric cancer specimens using quantitative PCR, immunohistochemistry, and western blotting. To investigate the functional significance of CXCL1 expression, a CXCL1 expression vector and short hairpin RNA targeting the CXCL1 or CXCR2 were transfected into gastric cancer cell lines to examine the biological outcomes of these cells. RESULTS: The expression of CXCL1 and CXCR2 was higher in gastric cancer tissues compared with adjacent noncancerous tissues. The upregulation of CXCL1 correlated significantly with tumor progression, advanced stage of gastric cancer patients, and was one of the independent prognostic factors for patient's survival. Furthermore, cancer cells expressing CXCL1 stably exhibited an increase in their migration and invasion ability, whereas CXCL1 or CXCR2 depletion significantly reduced the migration and invasion ability of each cell line. CONCLUSIONS: These results provide strong evidence that CXCL1 plays an important role in gastric cancer progression and migration and suggest that CXCL1 is a promising marker for the detection and prognosis of gastric cancer.

Cathepsin H regulated by the thyroid hormone receptors associate with tumor invasion in human hepatoma cells.

Thyroid hormone, 3, 3', 5-triiodo-L-thyronine (T(3)), mediates cell growth, development and differentiation by binding to its nuclear receptors (TRs). The role of TRs in cancer is still undefined. Notably, hyperthyroxinemia has been reported to influence the rate of colon cancer in an experimental model of carcinogenesis in rats. Previous microarray analysis revealed that cathepsin H (CTSH) is upregulated by T(3) in HepG2-TR cells. We verified that mRNA and protein expression of CTSH are induced by T(3) in HepG2-TR cells and in thyroidectomized rats following administration of T(3). The possible thyroid hormone-responsive elements of the CTSH promoter localized to the nucleotides -2038 to -1966 and -1565 to -1501 regions. An in vitro functional assay showed that CTSH can increase metastasis. J7 cells overexpressing CTSH were inoculated into severe combined immune-deficient mice and these J7-CTSH mice displayed a greater metastatic potential than did J7-control mice. The clinicopathologic significance of CTSH expression in hepatocellular carcinoma (HCC) was also investigated. The CTSH overexpressing in HCC was associated with the presence of microvascular invasion (P=0.037). The microvascular invasion characteristic is closely related to our in vitro characterization of CTSH function. Our results show that T(3)-mediated upregulation of CTSH led to matrix metallopeptidase or extracellular signal-regulated kinase activation and increased cell migration. This study demonstrated that CTSH overexpression in a subset hepatoma may be TR dependent and suggests that this overexpression has an important role in hepatoma progression.

Long-term results of Taiwan Pediatric Oncology Group studies 1997 and 2002 for childhood acute lymphoblastic leukemia.

The long-term outcome of 1390 children with acute lymphoblastic leukemia (ALL), treated in two successive clinical trials (Taiwan Pediatric Oncology Group (TPOG)-ALL-97 and TPOG-ALL-2002) between 1997 and 2007, is reported. The event-free survival improved significantly (P=0.0004) over this period, 69.3+/-1.9% in 1997-2001 to 77.4+/-1.7% in 2002-2007. A randomized trial in TPOG-97 testing L-asparaginase versus epidoxorubicin in combination with vincristine and prednisolone for remission induction in standard-risk (SR; low-risk) patients yielded similar outcomes. Another randomized trial, in TPOG-2002, showed that for SR patients, two reinduction courses did not improve long-term outcome over one course. Decreasing use of prophylactic cranial irradiation in the period 1997-2008 was not associated with increased rates of CNS relapse, prompting complete omission of prophylactic cranial irradiation from TPOG protocols, beginning in 2009. Decreased use of etoposide and cranial irradiation likely contributed to the low incidence of second cancers. High-risk B-lineage ALL, T-cell, CD10 negativity, t(9;22), infant, and higher leukocyte count were consistently adverse factors, whereas hyperdiploidy >50 was a consistently favorable factor. Higher leukocyte count and t(9;22) retained prognostic significance in both TPOG-97 and TPOG-2002 by multivariate analysis. Although long-term outcome in TPOG clinical trials is comparable with results being reported worldwide, the persistent strength of certain prognostic variables and the lower frequencies of favorable outcome predictors, such as ETV6-RUNX1 and hyperdiploidy >50, in Taiwanese children warrant renewed effort to cure a higher proportion of patients while preserving their quality of life.

Haematopoietic stem cell transplantation in Taiwan: past, present, and future.

In Taiwan, haematopoietic stem cell transplantation (HSCT) has been used to treat patients with haematological diseases since 1983. Thereafter till 2007, there were 2537 patients who had undergone HSCT in more than 15 hospitals. Their diseases included acute myeloid leukaemia in 27.8% of cases, non-Hodgkin's lymphoma 23.3%, acute lymphoblastic leukaemia 12.8%, chronic myeloid leukaemia 11.9%, severe aplastic anaemia 8.7%, and multiple myeloma 4.1%. Most of the cases received myeloablative conditioning regimens. More than 15% of cases received non-myeloablative regimens, and the mean age of these cases was at least 10 years older than those who received myeloablative regimens. The types of graft included peripheral blood (60.4%) and bone marrow (32.0%). A total of 35% of patients received autologous grafts. Of 1557 allogeneic HSCT patients, 338 (21.7%) received grafts from unrelated donors. Cord blood transplantation has been successfully performed in paediatric patients with thalassaemia major and with a large body size, and adult patients. The incidence of acute graft-versus-host disease was relatively low in Taiwan. On the contrary, a relatively higher proportion of hepatitis B carrier in the recipients had led to a higher incidence of reactivation hepatitis, which was markedly decreased following lamivudine prophylaxis. In conclusion, HSCT has become a routine therapy for major medical centres in Taiwan. Our unique experiences in the past decades also contributed to the progress of HSCT. With the establishment of professional association and patient supportive groups, we hope we can fully improve our daily practice and clinical as well as basic research in HSCT.

Long-term outcome of allogeneic human leukocyte antigen-matched sibling-donor peripheral blood stem cell transplantation in leukaemia patients.

Between 1993 and July 2008, a total of 354 leukaemic patients received either allogeneic bone marrow transplantation (BMT) [n = 180] or peripheral blood stem cell transplantation (PBSCT) [n = 174] from human leukocyte antigen-matched sibling donors. Graft-versus-host disease (GVHD) prophylaxis consisted of cyclosporin A and methotrexate. When comparing with BMT group, patients in the PBSCT group received much higher nucleated cells and CD34+ cells, and had much faster recovery of the neutrophil and platelet counts. The probability of developing acute GVHD was slightly higher in PBSCT patients (P = 0.02). The probability of chronic GVHD (cGVHD) in PBSCT was much higher in PBSCT (70 +/- 5.4%, extensive 48 +/- 6.5%) than in BMT (25 +/- 4.7%, extensive 10 +/- 3.4%; P < 0.001). Chronic GVHD was associated with long-term impairment of life quality and decreased quality-adjusted survival. In standard-risk leukaemia, use of PBSCT was associated with higher cGVHD, transplant-related mortality and a trend for decreased overall survival. The results suggest that allogeneic PBSCT is associated with high incidence of cGVHD in Chinese patients and its long-term risk and benefit remains to be defined in early stage of leukaemia.

Poor outcome in post transplant lymphoproliferative disorder with pulmonary involvement after allogeneic hematopoietic SCT: 13 years' experience in a single institute.

EBV-induced post transplant lymphoproliferative disorder (PTLD) continues to be a major complication after transplantation. Between January 1993 and April 2006, 12 cases of B-cell lymphoproliferative disorder were identified among 577 patients after allogeneic hematopoietic SCT (HSCT) with an overall incidence of 2.51% at 1 year. Grades II-IV acute GVHD, CMV antigenemia and the use of antithymocyte globulin (ATG) were independent risk factors for PTLD. At diagnosis, all of the tumors were CD20-positive and 11 (92%) were EBV-encoded RNA (EBER)-positive. Of the 12 patients with B-cell lymphoproliferative disorder, 8 had pulmonary involvement and 10 had extranodal involvement. Eleven patients received weekly rituximab therapy at a dose of 375 mg/m(2); the median interval between the onset of symptoms and rituximab therapy was 6 days. The overall mortality rate was 92% and seven (64%) of the deaths were directly attributable to disseminated PTLD within days or weeks of presentation. In our series, pulmonary PTLD followed an extremely aggressive course and poor response to current therapy, even though rituximab was included in the therapeutic regimens.

Persistent knee instability following revision total knee arthroplasty.

Instability is an important cause of failure following total knee arthroplasty (TKA). Knee stability needs to be optimal in both the coronal and sagittal planes. We describe failed revision TKA with persistent deformity and instability secondary to a deficient medial collateral ligament in a 71-year-old Chinese woman. Revision knee arthroplasty using constrained implants was performed on her with good result. During both primary and revision TKA, assessment of knee stability is critical. Constrained prosthesis would need to be considered when there is significant ligamentous deficiency.

Visualization of Rab3A dissociation during exocytosis: a study by total internal reflection microscopy.

Rab3A is a small G protein in the Rab3 subfamily, and is thought to act at late stage of exocytosis. However, the detailed mechanism of its action is not completely understood. To study the role of Rab3A in exocytosis, we used a total internal reflection fluorescence microscope to examine the fluorescence changes of EGFP-Rab3A-labeled and NPY-EGFP-labeled vesicles in PC12 cells upon stimulation. The fluorescence of EGFP-Rab3A-labeled and NPY-EGFP-labeled vesicles decreased while showing different patterns. The NPY-EGFP-labeled vesicles that exocytosed showed a transient fluorescence increase before NPY-EGFP fluorescence disappearance, which represents fusion and NPY release. This transient increase was diminished in cells that co-expressed the GDP-bound Rab3A mutant. The fluorescence of EGFP-Rab3A-labeled vesicles dispersed before disappearance, which represents the dissociation of Rab3A from the vesicles. The dispersion was not found in GTP-bound Rab3A mutant-labeled vesicles. Interestingly, EGFP-Rab3A F59S, a mutant unable to bind rabphilin, dissociates slower from the vesicles than wild type Rab3A and caused a slower release of NPY-EGFP. The results provide direct evidence to support the hypothesis that GTP hydrolysis and rabphilin are involved in Rab3A dissociation from the vesicles and the occurrence of exocytosis.