Liver histopathological lesions is severe in patients with normal alanine transaminase and low to moderate hepatitis B virus DNA replication

BACKGROUND

Chronic hepatitis B virus (HBV) infection remains a major global public health problem. Chronic hepatitis B (CHB) patients can be divided into treatment indication and non-treatment indication individuals according to alanine transaminase (ALT), HBV DNA, serum hepatitis B e antigen status, disease status [liver cirrhosis, hepatocellular carcinoma (HCC), or liver failure], liver necroinflammation or fibrosis, patients' age, and family history of HCC or cirrhosis. For example, normal ALT patients in 'immune-tolerant' phase with HBV DNA higher than 107 or 2 × 107 IU/mL, and those in 'inactive-carrier' phase with HBV DNA lower than 2 × 103 IU/mL do not require antiviral therapy. However, is it reasonable to set the defined values of HBV DNA as the fundamental basis to estimate the disease state and to determine whether to start treatment? In fact, we should pay more attention to those who do not match the treatment indications (gray-zone patients both in the indeterminate phase and in the 'inactive-carrier' phase).

AIM

To analyze the correlation of HBV DNA level and liver histopathological severity, and to explore the significance of HBV DNA for CHB with normal ALT.

METHODS

From January 2017 to December 2021, a retrospective cross-sectional set of 1299 patients with chronic HBV infection (HBV DNA > 30 IU/mL) who underwent liver biopsy from four hospitals, including 634 with ALT less than 40 U/L. None of the patients had received anti-HBV treatment. The degrees of liver necroinflammatory activity and liver fibrosis were evaluated according to the Metavir system. On the basis of the HBV DNA level, patients were divided into two groups: Low/moderate replication group, HBV DNA ≤ 107 IU/mL [7.00 Log IU/mL, the European Association for the Study of the Liver (EASL) guidelines] or ≤ 2 × 107 IU/mL [7.30 Log IU/mL, the Chinese Medical Association (CMA) guidelines]; high replication group, HBV DNA > 107 IU/mL or > 2 × 107 IU/mL. Relevant factors (demographic characteristics, laboratory parameters and noninvasive models) for liver histopathological severity were analyzed by univariate analysis, logistics analysis and propensity score-matched analysis.

RESULTS

At entry, there were 21.45%, 24.29%, and 30.28% of the patients had liver histopathological severities with ≥ A2, ≥ F2, and ≥ A2 or/and ≥ F2, respectively. HBV DNA level (negative correlation) and noninvasive model liver fibrosis 5 value (positive correlation) were independent risk factors for liver histopathological severities (liver necroinflammation, liver fibrosis, and treatment indication). The AUROCs of the prediction probabilities (PRE_) of the models mentioned above (< A2 vs ≥ A2, < F2 vs ≥ F2, < A2 and < F2 vs ≥ A2 or/and ≥ F2) were 0.814 (95%CI: 0.770-0.859), 0.824 (95%CI: 0.785-0.863), and 0.799 (95%CI: 0.760-0.838), respectively. HBV DNA level (negative correlation) was still an independent risk factor when diagnostic models were excluded, the P values (< A2 vs ≥ A2, < F2 vs ≥ F2, < A2 and < F2 vs ≥ A2 or/and ≥ F2) were 0.011, 0.000, and 0.000, respectively. For the propensity score-matched pairs, whether based on EASL guidelines or CMA guidelines, the group with significant liver histology damage (≥ A2 or/and ≥ F2) showed much lower HBV DNA level than the group with non- significant liver histology damage (< A2 and < F2). Patients in the moderate replication group (with indeterminate phase) had the most serious liver disease pathologically and hematologically, followed by patients in the low replication group (with 'inactive-carrier' phase) and then the high replication group (with 'immune-tolerant' phase).

CONCLUSION

HBV DNA level is a negative risk factor for liver disease progression. The phase definition of CHB may be revised by whether the level of HBV DNA exceeds the detection low limit value. Patients who are in the indeterminate phase or 'inactive carriers' should receive antiviral therapy.

Cytoreduction surgery and hyperthermic intraperitoneal chemotherapy for treating advanced peritoneal metastases of hepatocellular carcinoma

BACKGROUND

An effective treatment strategy for peritoneal metastasis (PM) of hepatocellular carcinoma (HCC-PM) has yet to be established. Although cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) have shown favorable outcomes in certain malignancies, their role in peritoneal metastatic HCC is unclear. Herein, we present a series of patients with HCC-PM treated with CRS/HIPEC and evaluate their outcomes.

METHODS

Records of patients with HCC-PM who had undergone CRS/HIPEC at the Hyperthermia Center of Yuan's General Hospital, Kaohsiung, Taiwan, between September 2015 and December 2016 were reviewed retrospectively. Patients were followed up until September 2019. We assessed the clinical courses and outcomes of these patients to clarify the benefits of CRS/HIPEC.

RESULTS

Six patients were included in our study. HCC-PM occurred synchronously in one patient and occurred metachronously in five patients after therapeutic minimally invasive procedures, including radiofrequency ablation, laparoscopic hepatectomy, robotic hepatectomy or spontaneously. The median peritoneal cancer index was 18.5. All patients experienced complete peritoneal cytoreduction without perioperative mortality. One patient had two CTCAE grade 3 complications. The median follow-up was 16 months. The median overall survival was 15.7 months. Four patients died of lung metastasis or liver failure owing to intrahepatic recurrence. The survival rates observed at 1, 2, and 4 years were 66.7%, 33.3%, and 33.3%, respectively.

CONCLUSIONS

CRS followed by HIPEC is feasible in patients with HCC-PM and might provide selected patients a chance for local disease control and longer survival. CRS/HIPEC might be considered as a treatment option in highly selected patients, as part of multimodal therapy approaches.

[Therapeutic effect of IGF-1R-targeting inhibitor (TAE226) on malignant pleural effusion in nude mice]

OBJECTIVE

To study the therapeutic effect of IGF-1R inhibitor TAE226 on malignant pleural effusion (MPE) in nude mice.

METHODS

Human lung carcinoma A549 cells were injected into the pleural cavity of nude mice to establish MPE model. The mice were randomly divided into model group and treatment group, and were orally administered with distilled water and TAE226 (20 mg/kg) in the same volume, respectively. The volume of pleural effusion and tumor weight of the two groups were observed. HE staining was used to reveal the histological changes and enzyme-linked immunosorbent assay (ELISA) was used to detect the IGF-1R protein expression. IGF-1R mRNA level in the tumor tissue was determined by RT-PCR. Microvessel density (MVD) and cell proliferation index (PI) were assessed by immunohistochemical analysis. The protein expression levels of IGF-1R, p-IGF-1R, PI3K and p-PI3K in the tumor tissue were determined by Western blotting.

RESULTS

The volumes of pleural effusion were (241.4±89.7) μl and (121.7±78.8) μl in the model and treatment groups, respectively (P<0.05). The tumor weight of treatment group was (316.7±186.3) mg, significantly lower than that of the model group (671.4±281.4) mg (P<0.05). RT-PCR analysis showed that IGF-1R mRNA level was 0.914±0.029 in the treatment group, significantly lower than that of the model group (1.152±0.037, P<0.01). The ELISA data revealed that IGF-1R protein expression level of the model group was significantly higher than that of the treatment group [(41.0±4.7) μg/L vs. (24.0±3.1) μg/L, P<0.01]. Immunohistochemical analysis showed that there were significant differences between MVD and PI in the model and treatment groups [MVD, 34.75±3.49 vs. 22.25±3.63; PI, (75.25±7.15)% vs. (45.75±5.12)%; P<0.01 for both). Western blot data showed that IGF-1R and PI3K protein expression levels were not significantly different between the model and treatment groups (1.03±0.33 vs. 0.98±0.37 and 1.05±0.28 vs. 0.98±0.19), respectively (P>0.05), but p-IGF-1R and p-PI3K protein expression levels had significant differences between the two groups (1.08±0.10 vs. 0.51±0.08 and 1.12±0.09 vs. 0.86±0.09), respectively (P<0.01 for both).

CONCLUSIONS

The IGF-1R inhibitor can effectively inhibit the formation of malignant pleural effusion. Its mechanism may be related to the suppression of tumor cell proliferation, invasion and angiogenesis through inhibition of PI3K signaling. TAE226 treatment may be a potential therapeutic regimen of treating malignant pleural effusion.

2,3,5,4'-tetrahydroxystilbene-2-O-β-D-glucoside suppresses human colorectal cancer cell metastasis through inhibiting NF-κB activation

2,3,5,4'-tetrahydroxystilbene-2-O-β-D-glucoside (THSG), a major component of Polygonum multiflorum Thunb (He-Shou-Wu), has been reported to exhibit antioxidant and anti-inflammatory effects. However, its anti-metastatic effect against colorectal cancer is still unclear. In this study, cell migration, invasion and adhesion abilities as well as metastasis-associated protein and NF-κB pathway signaling factor expression were analyzed after treating HT-29 cells with THSG. According to the results, the migration and invasiveness of HT-29 cells were reduced after treatment with 5 or 10 mM THSG (p<0.05). Additionally, the levels of matrix metalloproteinase-2 (MMP-2) and phosphorylated VE-cadherin in HT-29 cells were reduced and the transepithelial electrical resistance (TEER) of EA.hy926 endothelial cell monolayers was increased after incubation in THSG for 24 h (p<0.05). Cell adhesion ability and the E-selectin and intercellular adhesion molecule-1 (ICAM-1) protein levels were reduced when EA.hy926 endothelial cells were treated with THSG (p<0.05). In addition, the cytoplasmic phosphorylation of IκB, the nuclear p65 level and the DNA-binding activity of NF-κB were reduced after treating HT-29 or EA.hy926 cells with 5 or 10 mM THSG (p<0.05). These results suggest that THSG inhibits HT-29 cell metastasis by suppressing cell migration, invasion and adhesion. Furthermore, THSG inhibits metastasis-associated protein expression by suppressing NF-κB pathway activation.

Effects of Dang-Gui-Bu-Xue-Tang, an herbal decoction, on iron uptake in iron-deficient anemia

Dang-Gui-Bu-Xue-Tang (DBT), a combination of Angelicae Sinensis Radix and Astragali Radix, is a widely used herbal decoction in traditional Chinese medicine primarily to promote or invigorate the “blood”. In this study, we explored this ancient formulation and provide evidence of its blood-toning properties. We used the improvement iron uptake as promote or invigorate the “blood” indicator. Ferritin formation of Caco-2 cells in vitro assay and diet-induced anemia (DIA) in rat model were used to prove its improvement iron uptake and ameliorating effects. Finally, the iron–DBT interactions were measured by iron-binding assay. We first demonstrated DBT increased uptake of ferrous iron through the biosynthesis of ferritin by Caco-2 cells and determined which complementary treatment would provide optimum results. Thereafter, effects of the treatment on improving the bioavailability of absorbed iron in the form of hemoglobin (Hb) were established using a DIA-animal model. The results showed that DBT slightly improved Hb levels compared with the baseline Hb and pretreatment with DBT for 2 hours prior to supplementation with ferrous sulfate provided the greatest gain in Hb levels in DIA rats. However, DBT and ferrous sulfate were co-treated with Caco-2 cell or DIA rats, the ferritin formation and Hb levels both were decreased. In iron-binding assay, the DBT extract influenced the free Fe(II) type in the FeSO₄ solution. Therefore, we suggest that complementary treatment with DBT and iron supplementation can have a strong ameliorating effect on iron-deficiency anemia in clinical settings, but needs a 2-hour interval of DBT administration prior to ferrous sulfate treatment.

Vitis thunbergii var. taiwaniana Extracts and Purified Compounds Ameliorate Obesity in High-Fat Diet-Induced Obese Mice

The increasing prevalence of obesity continues to gain more attention worldwide. In this study, diet-induced obese mice were used to evaluate the antiobesity effects of extracts, fractions, and purified compounds from Vitis thunbergii var. taiwaniana (VTT). The C57BL/6J mice were fed a 5-week high-fat diet (HF) concurrently with ethanol extracts (Et-ext, 80 mg/kg) from roots (R), stems (S), and leaves (L) by oral gavage daily. Only R-Et-ext interventions showed significant weight reduction in mice compared with those in the HF group; however, mouse plasma contents of total cholesterols (TC), total triglycerides (TG) and low-density lipoproteins (LDL) of all three Et-ext intervened groups showed significant reductions compared with those in the HF group. Furthermore, intervention with the ethyl acetate-partitioned fraction (EA-fra, 60 mg/kg) from R-Et-ext but not the n-butanol-partitioned fraction or water fraction from R-Et-ext showed significant weight reduction in mice compared with those in the HF group. The same molecular weights of three resveratrol tetramers, (+)-hopeaphenol, (+)-vitisin A, and (-)-vitisin B, were isolated from the EA-fra of VTT-R. The (+)-vitisin A and fenofibrate (25 mg/kg) but not the (+)-hopeaphenol and (-)-vitisin B interventions showed significant weight reduction in mice compared with those in the HF group. The total feed intake among the HF groups with or without interventions showed no significant differences. The mouse plasma contents of TC, TG, LDL, free fatty acid, and plasma lipase activity of the three resveratrol tetramer-intervened groups showed reductions in the mice compared with those in the HF group. It was proposed that the lipase inhibitory activities of VTT extracts and purified resveratrol tetramers might contribute in part to the antiobesity effect, and these results suggested that VTT may be developed as functional food for achieving antiobesity objectives and requires further investigation.

A distinct immunogenic region of glutamic acid decarboxylase 65 is naturally processed and presented by human islet cells to cytotoxic CD8 T cells

CD8 T cells specific for islet autoantigens are major effectors of β cell damage in type 1 diabetes, and measurement of their number and functional characteristics in blood represent potentially important disease biomarkers. CD8 T cell reactivity against glutamic acid decarboxylase 65 (GAD65) in HLA-A*0201 subjects has been reported to focus on an immunogenic region 114-123 (VMNILLQYVV), with studies demonstrating both 114-123 and 114-122 epitopes being targeted. However, the fine specificity of this response is unclear and the key question as to which epitope(s) β cells naturally process and present and, therefore, the pathogenic potential of CD8 T cells with different specificities within this region has not been addressed. We generated human leucocyte antigen (HLA)-A*0201-restricted CD8 T cell clones recognizing either 114-122 alone or both 114-122 and 114-123. Both clone types show potent and comparable effector functions (cytokine and chemokine secretion) and killing of indicator target cells externally pulsed with cognate peptide. However, only clones recognizing 114-123 kill target cells transfected with HLA-A*0201 and GAD2 and HLA-A*0201(+) human islet cells. We conclude that the endogenous pathway of antigen processing by HLA-A*0201-expressing cells generates GAD65114-123 as the predominant epitope in this region. These studies highlight the importance of understanding β cell epitope presentation in the design of immune monitoring for potentially pathogenic CD8 T cells.

Modification of human islet preparation: an effective approach to improve graft outcome after islet transplantation?

Revascularisation of transplanted islets is an essential prerequisite for graft survival and function. However, current islet isolation procedures deprive the islets of endothelial tubulets. This may have a detrimental effect on the revascularisation process of islets following transplantation. We hypothesise that modification of the isolation procedure that preserves islet endothelial vessels may improve the islet revascularisation process following transplantation. Here, we present a modified islet isolation method by which a substantial amount of endothelial cells still attached to the islets could be preserved. The islets with preserved endothelial cells isolated by this method were revascularised within 3 days, not observed in islets isolated by standard methods. Further, we observed that grafts of islets isolated by standard methods had more patches of dead tissue than islet grafts obtained by the modified method, indicating that attached endothelial cells may play an important role in the islet revascularisation process and potentially help to improve the transplantation outcome.

Curcumin-induced Aurora-A suppression not only causes mitotic defect and cell cycle arrest but also alters chemosensitivity to anticancer drugs

Overexpression of oncoprotein Aurora-A increases drug resistance and promotes lung metastasis of breast cancer cells. Curcumin is an active anticancer compound in turmeric and curry. Here we observed that Aurora-A protein and kinase activity were reduced in curcumin-treated human breast chemoresistant nonmetastatic MCF-7 and highly metastatic cancer MDA-MB-231 cells. Curcumin acts in a similar manner to Aurora-A small interfering RNA (siRNA), resulting in monopolar spindle formation, S and G2/M arrest, and cell division reduction. Ectopic Aurora-A extinguished the curcumin effects. The anticancer effects of curcumin were enhanced by Aurora-A siRNA and produced additivity and synergism effects in cell division and monopolar phenotype, respectively. Combination treatment with curcumin overrode the chemoresistance to four Food and Drug Administration (FDA)-approved anticancer drugs (ixabepilone, cisplatin, vinorelbine, or everolimus) in MDA-MB-231 cells, which was characterized by a decrease in cell viability and the occurrence of an additivity or synergy effect. Ectopic expression of Aurora-A attenuated curcumin-enhanced chemosensitivity to these four tested drugs. A similar benefit of curcumin was observed in MCF-7 cells treated with ixabepilone, the primary systemic therapy to patients with invasive breast cancer (stages IIA-IIIB) before surgery. Antagonism effect was observed when MCF-7 cells were treated with curcumin plus cisplatin, vinorelbine or everolimus. Curcumin-induced enhancement in chemosensitivity was paralleled by significant increases (additivity or synergy effect) in apoptosis and cell cycle arrest at S and G2/M phases, the consequences of Aurora-A inhibition. These results suggest that a combination of curcumin with FDA-approved anticancer drugs warrants further assessment with a view to developing a novel clinical treatment for breast cancer.

Immunomodulatory effects of Hedysarum polybotrys extract in mice macrophages, splenocytes and leucopenia

Astragali Radix (Huang-Qi) is a popular herbal medicine commonly used as a constituent in tonic herbal preparations. Hedysarum polybotrys Handel-Mazzetti is one species used of Astragali Radix. In this study, the immunomodulatory properties of H. polybotrys were explored by LPS-activated and SNP-treated RAW 264.7 cells and splenocytes and, daunoblastina-induced leucopenia BALB/c mice. Formononetin was used as the bioactive marker to monitor the quality of the H. polybotrys extracts. H. polybotrys was extracted with hot-water and methanol, and MeOH extract partitioned with H₂O (M-H) and ethyl acetate (M-EA) to yield four different fractions. M-EA had the highest formononetin and total proanthocyanidin content and showed stronger inhibitory effects on the production and expression of NO, PGE₂, iNOS and COX-2 in LPS-activated RAW 264.7 cells and splenocytes than the other fractions. In addition, M-EA significantly stimulated the proliferation of LPS-activated RAW 264.7 cells and splenocytes, enhanced NO radicals scavenging and attenuated NO-induced cytotoxicity. Furthermore, M-EA also significantly increased the rate of recovery of white blood cells level in daunoblastina-induced leucopenia mice. These evidences suggest that this traditional Qi-tonifying herb has potential effects in clinical conditions when immune-enhancing and anti-inflammatory effect is desired.

Attainment of metabolic goals in the integrated UK islet transplant program with locally isolated and transported preparations

The objective was to determine whether metabolic goals have been achieved with locally isolated and transported preparations over the first 3 years of the UK's nationally funded integrated islet transplant program. Twenty islet recipients with C-peptide negative type 1 diabetes and recurrent severe hypoglycemia consented to the study, including standardized meal tolerance tests. Participants received a total of 35 infusions (seven recipients: single graft; 11 recipients: two grafts: two recipients: three grafts). Graft function was maintained in 80% at [median (interquartile range)] 24 (13.5-36) months postfirst transplant. Severe hypoglycemia was reduced from 20 (7-50) episodes/patient-year pretransplant to 0.3 (0-1.6) episodes/patient-year posttransplant (p < 0.001). Resolution of impaired hypoglycemia awareness was confirmed [pretransplant: Gold score 6 (5-7); 24 (13.5-36) months: 3 (1.5-4.5); p < 0.03]. Target HbA1c of <7.0% was attained/maintained in 70% of recipients [pretransplant: 8.0 (7.0-9.6)%; 24 (13.5-36) months: 6.2 (5.7-8.4)%; p < 0.001], with 60% reduction in insulin dose [pretransplant: 0.51 (0.41-0.62) units/kg; 24 (13.5-36) months: 0.20 (0-0.37) units/kg; p < 0.001]. Metabolic outcomes were comparable 12 months posttransplant in those receiving transported versus only locally isolated islets [12 month stimulated C-peptide: transported 788 (114-1764) pmol/L (n = 9); locally isolated 407 (126-830) pmol/L (n = 11); p = 0.32]. Metabolic goals have been attained within the equitably available, fully integrated UK islet transplant program with both transported and locally isolated preparations.

Cannabinoid receptor agonists and antagonists stimulate insulin secretion from isolated human islets of Langerhans

AIMS

The role of cannabinoid receptors in human islets of Langerhans has not been investigated in any detail, so the current study examined CB1 and CB2 receptor expression by human islets and the effects of pharmacological cannabinoid receptor agonists and antagonists on insulin secretion.

METHODS

Human islets were isolated from pancreases retrieved from heart-beating organ donors. Messenger RNAs encoding human CB1 and CB2 receptors were amplified from human islet RNA by RT-PCR and receptor localization within islets was identified by immunohistochemistry. Dynamic insulin secretion from human islets perifused with buffers supplemented with CB1 and CB2 receptor agonists and antagonists was quantified by radioimmunoassay.

RESULTS

RT-PCR showed that both CB1 and CB2 receptors are expressed by human islets and immunohistochemistry indicated that receptor expression co-localized with insulin-expressing β-cells. Perifusion experiments using isolated human islets showed that insulin secretion was reversibly stimulated by both CB1 and CB2 receptor agonists, with CB1 receptor activation associated with increased basal secretion whereas CB2 receptors were coupled to initiation and potentiation of insulin secretion. Antagonists at CB1 (N-(Piperidin-1-yl)-5-(4-iodophenyl)-1-(2,4-dichlorophenyl)-4-methyl-1H-pyrazole-3-carboxamide) and CB2 (N-(1,3-Benzodioxol-5-ylmethyl)-1,2-dihydro-7-methoxy-2-oxo-8-(pentyloxy)-3-quinoline carboxamide) receptors failed to inhibit the stimulatory effects of the respective agonists and, unexpectedly, reversibly stimulated insulin secretion.

CONCLUSIONS

These data confirm the expression of CB1 and CB2 receptors by human islets and indicate that both receptor subtypes are coupled to the stimulation of insulin secretion. They also implicate involvement of CB1/2 receptor-independent pathways in the antagonist-induced stimulatory effects.

Distribution and Prognosis of WHO Lymphoma Subtypes in Taiwan Reveals a Low Incidence of Germinal-Center Derived Tumors

To assess the distribution of lymphomas in Taiwan according to the WHO (World Health Organization) classification, 175 recently diagnosed cases of malignant lymphomas were studied and the clinicopathologic data were analyzed. B-cell lymphomas accounted for 57.1% of cases, T-cell lymphomas 38.9%, and Hodgkin's lymphoma 4%. Extranodal lymphomas predominated (55.4%). The most common subtype of B-cell lymphoma was diffuse large B-cell lymphoma (33.1%). All tumor types believed to be derived from germinal center (GC) B-cells including follicular lymphoma (4.6%), Burkitt lymphoma (1.7%), Hodgkin lymphoma (4.0%), and GC-like diffuse large B-cell lymphoma (as defined by combined expression of bc1-6 and CD10) were rather uncommon as compared to frequencies seen in series from Western countries. The common T-cell lymphomas included nasal and extranasal NK/T cell lymphoma (7.4%), mycosis fungoides (7.4%), and unspecified peripheral T-cell lymphoma (6.9%). Adult T-cell leukemia/lymphoma was very uncommon and accounts for only 0.6%. The proportional increase in T-cell lymphomas that were unrelated to type I human T-cell lymphotropic virus (HTLV-1) may be linked to differential Epstein-Barr virus (EBV) oncogenesis. The survival data revealed that mantle cell lymphoma, NK/T-cell lymphoma, unspecified peripheral T-cell lymphoma, and subcutaneous panniculitis-like T-cell lymphoma had an aggressive course. Our results confirm the utility of the WHO classification scheme for prognostic stratification and further highlight the distinctive distribution pattern of malignant lymphoma in Taiwan including the higher relative incidence of T cell lymphomas and the rarity of germinal center-derived B-cell tumors.

Effect of schisandrin B and sesamin mixture on CCl(4)-induced hepatic oxidative stress in rats

To study the effects of schisandrin B and sesamin mixture on carbon tetrachloride (CCl(4))-induced hepatic oxidative stress in male Sprague-Dawley rats. The rats were randomly assigned to five groups: control group (olive oil injection), CCl(4) group (CCl(4) injection), silymarin group (CCl(4) injection combined with supplementation of silymarin, 7.5 mg/kg/day), low dose group (CCl(4) injection combined with supplementation of schisandrin B and sesamin mixture at a low dose, 43 mg/kg/day) and high dose group (CCl(4) injection combined with the supplementation of schisandrin B and sesamin mixture at a high dose, 215 mg/kg/day). The hepatic superoxide dismutase and glutathione peroxidase activities of rats in the low dose and high dose groups were increased significantly compared with those in the CCl(4) group. The hepatic reduced glutathione concentration in the silymarin, low dose and high dose groups were increased significantly (48%, 45% and 53%, respectively) when compared with those of the CCl(4) group. In addition, the concentration of glutathione in the erythrocytes of the low dose group was significantly higher than the CCl(4) group by 25%. These results suggest that the schisandrin B-sesamin mixture exerted a hepatoprotective effect by improving the antioxidative capacity in rats under CCl(4)-induced hepatic oxidative stress.

Melioidotic necrotizing fasciitis presenting as a supraclavicular mass

Melioidosis is an infection caused by Burkholderia pseudomallei that usually involves the respiratory tract. It may manifest as pneumonia, septicemia, or localized infection. We present here a case of melioidosis initially manifesting as a mass over the supraclavicular area and subsequently progressing to necrotizing fasciitis. With appropriate antimicrobial treatment and adequate surgical debridement, localized melioidosis can be treated successfully. Melioidosis should be considered in the differential diagnosis of neck masses, especially in patients who have traveled to or stayed in an endemic area.

Distribution patterns of dendritic cells and T cells in diffuse large B-cell lymphomas correlate with prognoses

PURPOSE

Diffuse large B-cell lymphoma (DLBCL), the most common subtype of non-Hodgkin's lymphomas, accounts for 30% to 40% of all lymphoma cases. However, long-term survival by current chemotherapy was achieved in only 40% of patients, warranting the development of novel therapeutic strategies including T-cell immunotherapy. However, the level of baseline immune activation in DLBCL is unclear.

EXPERIMENTAL DESIGN

The density and distribution of dendritic cells and T cells in 48 cases of primary DLBCL was evaluated by immunohistochemistry.

RESULTS

Increased numbers of intratumoral CD1a+ dendritic cells and increased S100+ cells and CD45RO+ T cells around the edges of the tumors were seen in 10 of 48 (21%), 9 of 48 (19%), and 10 of 48 (21%) cases and these were correlated with a favorable prognosis (P = 0.015; P = 0.070, and P = 0.017, respectively), along with increased granzyme B+ T cells in tumor beds (P = 0.013). Increased peritumoral T cells were correlated with tumor expression of HLA-DR (r = 0.446; P = 0.002). Extranodal lymphomas showed fewer tumor-associated CD45RO+ T cells (r = -0.407; P = 0.001) and less conspicuous dendritic cell infiltrates.

CONCLUSIONS

In DLBCL, the presence of baseline antitumor immune response is associated with favorable clinical outcome, and thus adjuvant T-cell immunotherapy may further boost treatment responses.

Inability to process and store proinsulin in transdifferentiated pancreatic acinar cells lacking the regulated secretory pathway

Generation of new beta-cells from the adult pancreas or the embryonic stem cells is being pursued by research groups worldwide. Success will be dependent on confirmation of true beta-cell phenotype evidenced by capacity to process and store proinsulin. The aim of these studies was to robustly determine endocrine characteristics of the AR42J rat pancreatic acinar cell line before and after in vitro transdifferentiation. beta-cell phenotypic marker expression was characterised by RT-PCR, immunostaining, western blotting, ELISA and in human preproinsulin transgene over-expression studies in wild-type AR42J cells and after culture on Matrigel basement membrane matrix with and without growth/differentiation factor supplementation. Pancreatic duodenal homeobox 1 (PDX1), forkhead box transcription factor a2 (Foxa2), glucokinase, pancreatic polypeptide and low-level insulin gene transcription in wild-type AR42J cells were confirmed by RT-PCR. Culture on Matrigel-coated plates and supplementation of medium with glucagon-like peptide 1 induced expression of the beta-cell Glut 2 with maintained expression of insulin and PDX1. Increased biosynthesis and secretion of proinsulin were confirmed by immunocytochemical staining and sensitive ELISA. Absence of the regulated secretory pathway was demonstrated by undetectable prohormone convertase expression. In addition, inability to process and store endogenous proinsulin or human proinsulin translated from a constitutively over-expressed preproinsulin transgene was confirmed. The importance of robust phenotypic characterisation at the protein level in attempted beta-cell transdifferentiation studies has been confirmed. Rodent and human sensitive/specific differential proinsulin/insulin ELISA in combination with human preproinsulin over-expression enables detailed elucidatation of core endocrine functions of proinsulin processing and storage in putative new beta-cells.

Human islets derived from donors after cardiac death are fully biofunctional

Islets from brain-dead donors (BDDs) are being used in the treatment of Type 1 diabetes. However, both donor numbers and islet survival are limited. We explored the clinical potential for islets from non-heart-beating donors (NHBDs), who have lower circulating cytokines, by comparing islets from 10 NHBDs against 12 identically-isolated islets from BDDs over the same time period. The quantity and quality of islets from NHBDs was good. NHBD yielded approximately 12.6% more islets than those of BDDs (505,000 +/- 84,230 vs. 400,970 +/- 172,430 islet equivalent number [IEQ]/pancreas, p = 0.01) with comparable viability. ATP and GTP contents were lower (6.026 +/- 3.076 vs. 18.105 +/- 7.8 nM/mg protein, p = 0.01 and 1.52 +/- 0.87 vs. 3.378 +/- 0.83 nM/mg protein, p = 0.04) and correlated negatively to warm ischemia time (R(2)= 0.8022 and R(2)= 0.7996, respectively). Islets from NHBDs took longer to control hyperglycemia in diabetic mice, but were equally able to sustain euglycemia. With a warm ischemia time (WIT) of <or=25 min, islets from NHBDs are at least as competent as islets from BDDs and should be suitable for clinical use.

Requirement of MMP-3 in anchorage-independent growth of oral squamous cell carcinomas

BACKGROUND

Matrix metalloproteinase-3 (MMP-3) is expressed in various carcinomas; however, its function is not clearly established. This study was to assess its possible role in oral squamous cell carcinomas (OSCCs).

MATERIALS AND METHODS

Specimens of seven oral pre-malignant lesions (OPMLs) and 92 OSCCs were subjected to MMP-3 detection by RT-PCR and Western blot. Antisense oligodeoxynucleotides (AODNs) of MMP-3 were used to transfect OSCC (OECM-1 and SCC-9) and esophageal carcinoma (CE81T/VGH) cell lines, and their growth was subsequently analyzed by XTT and soft-agar colony assay.

RESULTS

MMP-3 transcript was preferentially expressed in OSCCs (71 of 92, 77%) than in OPMLs (two of seven, 29%; P = 0.012). Both MMP-3 transcript and protein levels were significantly higher in OSCC masses than in neighboring tissues (P < 0.0001 and P = 0.04, respectively). Growth of the three cell lines was not affected, while the colony numbers of OECM-1 and CE81T/VGH were significantly reduced by the transfection of MMP-3 AODNs (P = 0.002 and P = 0.004, respectively). SCC-9 did not form colonies in soft-agar/medium.

CONCLUSIONS

MMP-3 function may be required in most OSCCs, and it may support the anchorage-independent growth of both OSCC and esophageal carcinoma.

Gene expression heterogeneity in human islet endocrine cells in vitro: the insulin signalling cascade

AIMS/HYPOTHESIS

Insulin secretion is a highly regulated mechanism involving a complex insulin-dependent network of communication between alpha, beta and delta cells. However, whereas the role of insulin in beta cells has been well documented, very little is known about its role in alpha and delta cells. Having recently demonstrated heterogeneity of insulin receptor (INSR) isoform expression in these three endocrine cell types, our current study aimed to characterise the expression pattern of the multiple isoforms involved in the insulin signal transduction cascade in human alpha, beta and delta cells in vitro.

MATERIALS AND METHODS

cDNA samples prepared from single human islet cells were subjected to nested PCRs.

RESULTS

Of 706 cells analysed, 15% were alpha cells, 28% beta cells, 8% delta cells and 46% non-endocrine cells. Profiling of expression of the insulin signalling cascade elements showed a heterogeneity between islet cell types, although at least one member of each protein family was expressed in the three populations of endocrine cells. Thus, the mRNAs coding for INSR-B, phosphoinositide-dependent protein kinase-1 and the human homologue of v-akt murine thymoma viral oncogene homologue 1 (AKT1) could not be detected in alpha cells, but were expressed by beta and delta cells. In addition, while the insulin receptor substrates IRS1 and IRS2, phosphoinositide-3-kinase, catalytic, beta polypeptide (PIK3CB) and AKT2 were expressed with relatively low frequencies in alpha and delta cells (<17% for IRS1, IRS2, PIK3CB; <25% for AKT2), their frequencies of expression in beta cells were 50, 33, 33 and 100%, respectively.

CONCLUSIONS/INTERPRETATION

Our results suggest that insulin signalling cascade elements in human alpha, beta and delta cells have distinct expression patterns.

Wogonin but not Nor-wogonin inhibits lipopolysaccharide and lipoteichoic acid-induced iNOS gene expression and NO production in macrophages

Wogonin (Wog; 5,7-dihydroxy-8-methoxy flavone) has been shown to effectively inhibit lipopolysaccharide (LPS)-induced inducible nitric oxide synthase (iNOS) gene expression and nitric oxide production in our previous study. In the present study, we found that Nor-wogonin (N-Wog; 5,7,8-trihydroxyl flavone), a structural analogue of Wog with an OH substitution at C8, performed different effect on LPS- or lipoteichoic acid (LTA)-induced iNOS gene expression and nitric oxide (NO) production in macrophages. Wog, but not N-Wog, significantly inhibits LPS- or LTA-induced NO production through suppressing iNOS gene expression at both protein and mRNA without affecting NO donor sodium nitroprusside-induced NO production, NOS enzyme activity, and cells viability. Activation of JNKs (not ERKs) via phosphorylation induction, and an increase in c-Jun (not c-Fos) protein expression were involved in LPS- and LTA-treated RAW264.7 cells, and those events were blocked by Wog, but not N-Wog, addition. Furthermore, 5,7-diOH flavone, but not 5-OH flavone, 7-OH flavone, 5-OH-7-OCH(3) flavone, significantly inhibits LPS-induced iNOS protein expression and NO production, and 7,8-diOCH(3) flavone performs more effective inhibitory activity on LPS-induced NO production and iNOS protein expression than 7-OCH(3)-8-OH flavone. These data suggest that OHs at both C5 and C7 are essential for NO inhibition of flavonoids, and OCH(3) at C8 may contribute to this activity, and suppression of JNKs-c-Jun activation is involved.

Islet cell transplantation

People with type 1 diabetes have normal exocrine pancreatic function, making islet cell rather than whole organ transplantation an attractive option. Achieving insulin independence in type 1 diabetes was the perceived goal of islet cell transplantation. The success of the Edmonton group in achieving this in a selected group of type 1 patients has led to renewed optimism that this treatment could eventually replace whole organ pancreas transplantation. However the long-term results of this treatment indicate that insulin independence is lost with time in a significant proportion of patients, although they may retain glycaemic stability. In this context, the indications for islet cell transplantation, which have evolved over the last 5 years, indicate that the patients who benefit most are those who experience severe hypoglycaemic reactions despite optimal insulin therapy. This review will summarise the history of islet cell transplantation, islet isolation techniques, the transplant procedure, immunosuppressive therapy, indications for islet cell transplantation, current clinical trials, the early UK islet cell transplant experience using the Edmonton protocol, and some of the challenges that lie ahead.

Up-regulation of matrix metalloproteinase-8 by betel quid extract and arecoline and its role in 2D motility

Betel quid (BQ) and matrix metalloproteinase-8 (MMP-8) play roles in oral diseases. Here, we analyzed the regulation of MMP-8 by BQ and its effect on cell migration. We found that BQ extract (BQE) increased the secretion of an 85kDa caseinolytic proteinase, specifically precipitated by an anti-MMP-8 antibody, in the culture medium of OECM-1, an oral squamous cell carcinoma (OSCC) cell line. BQE also stimulated MMP-8 secretion in an esophageal carcinoma cell line, CE81T/VGH, in a dose-dependent manner, and MMP-8 protein was maximally expressed at 24h after BQE treatment in OECM-1. The BQE-induced MMP-8 expression was dose-dependently inhibited by PD98059. Arecoline, the major alkaloid of areca nut, was tested to dose-dependently up-regulate MMP-8 protein level. Moreover, both arecoline- (4.7-fold) and BQE-selected (5.5-fold) CE81T/VGH cells expressed higher MMP-8 protein level and exhibited enhanced two-dimensional (2D) motility (p=0.009 in both cells) than parental cells. The enhanced motility of arecoline- (p=0.006) and BQE-selected (p=0.002) cells was both specifically blocked by an anti-MMP-8 antibody. We conclude that BQ may accelerate tumor migration by stimulating MMP-8 expression through MEK pathway in at least some carcinomas of the upper aerodigestive tract. Furthermore, arecoline may be one of the positive MMP-8 regulators among BQ ingredients.

Immuno-enhancement effects of Huang Qi Liu Yi Tang in a murine model of cyclophosphamide-induced leucopenia

Tonic Chinese prescriptions are widely used in daily foods to improve health in Taiwan. Huang Qi Liu Yi Tang (HQLYT) is one such tonic Chinese prescription. In this study, the immuno-enhancement effects of HQLYT tonic were explored using an in vitro splenocyte proliferation assay and by evaluating improvements in cyclophosphamide-induced leucopenia in a BaLb/c mice model. HQLYT is composed of Radix Astragali, licorice, and jujube, and extracted in boiling water. The contents of glycyrrhizin and formononetin were used as bioactive markers to control the quality of the HQLYT water extract, at 7.26+/-0.04mg/g and 112.07+/-0.08 micro g/g, respectively. In the in vitro assay, HQLYT (12.5 micro g/ml) showed better immuno-enhancing effects than Radix Astragali, licorice, or jujube alone, and enhanced the survival rate of splenocytes by 88%. Moreover, HQLYT significantly enhanced the cytotoxic effects of natural killer cells of splenocytes against YAC-1 cells. The BaLb/c mice were fed HQLYT once a day for 14 days. After oral treatment with HQLYT 400mg/kg body weight (BW), the IL-2 release in BaLb/c mice and the natural killer cell activity of the splenocytes were both enhanced, and the WBC level of cyclophosphamide-induced leucopenic mice was improved by treatment with 400mg HQLYT/kgBW. HQLYT significantly delayed the decline in the WBC level and affected a faster recovery of the WBC level back to a normal status. In summary, HQLYT enhanced immunologic functions in both in vitro and in vivo studies. These results offer scientific evidence to prove the efficacy of this tonic Chinese prescription.

Cefotaxime-ciprofloxacin combination therapy for nontyphoid Salmonella bacteremia and paravertebral abscess after failure of monotherapy

Therapeutic failure of monotherapy with either a third-generation cephalosporin or a fluoroquinolone against nontyphoid salmonellae has been observed in clinical practice. Combination therapy with both agents is recommended in the literature for treating life-threatening infections. However, we know of no published case reports that indicate a therapeutic advantage of this combination therapy for nontyphoid salmonellae infections. We describe a 60-year-old man who had breakthrough bacteremia with vertebral osteomyelitis and paravertebral abscess caused by Salmonella enterica serotype Choleraesuis. This was not controlled with sequential monotherapy but was eventually cured with cefotaxime-ciprofloxacin combination therapy. The Etest showed that the strain was susceptible to cefotaxime and ciprofloxacin, but resistant to nalidixic acid. Cefotaxime and ciprofloxacin in combination may be considered as an option for difficult-to-treat salmonellosis.

Typhoid fever complicated by multiple organ involvement: report of two cases

Typhoid fever complicated by multiple organ involvement has been rarely mentioned in the literature. We reported two cases of typhoid fever with several unusual manifestations, including acute renal failure, acute hepatitis, acute pancreatitis, disseminated intravascular coagulation, and lower gastrointestinal bleeding. A renal biopsy in the first case showed no pathological change. Bone marrow biopsy showed focal necrosis of matrix, which might have been due to severe illness. A liver biopsy in the second case showed a predominantly histiocytic proliferation with occasional neutrophilic infiltration in the portal areas and hepatic sinusoids. Focal necrosis, bile duct injury, and multiple eosinophilic bodies were also noted. After appropriate antimicrobial therapy, both patients recovered without any sequelae. The potential of multiple organ involvement is highlighted in typhoid fever, which, on rare occasions, may occur simultaneously in the same patient.

Clinical experiences of the infections caused by extended-spectrum beta-lactamase-producing Serratia marcescens at a medical center in Taiwan

CTX-M-3 has become the most common extended-spectrum beta-lactamase (ESBL) produced by Serratia marcescens in Taiwan. An expanded effort to detect ESBL among 123 nonrepetitive isolates of S. marcescens was made and 15 (12%) ESBL-producers were identified, all revealing CTX-M-3. Without routinely detecting the ESBL for S. marcescens in clinical laboratories, 80% of the ESBL-producers were reported to be susceptible to cefepime. The clinical spectrum of ESBL-producing S. marcescens-related infections included febrile urinary tract infection (n = 3); afebrile pyuria (n = 2); pneumonia (n = 3); spontaneous bacterial peritonitis (n = 3); secondary bacteremia (n = 2) and one each with primary bacteremia and colonization of the central catheter tip. Overall, the 30-day mortality rate was 33.3% (5/15) and the outcome depended on the severity of the underlying disorder and infection per se. In conclusion, although our case numbers were limited, due to the substantial incidence and associated mortality of ESBL-producing S. marcescens and its potential treatment failure by an apparently susceptible cephalosporin, we recommend that the detection and report of ESBL production for S. marcescens in clinical laboratories be made mandatory.

Dominant-negative Rac1 suppresses Ras-induced apoptosis possibly through activation of NFκB in Ha-ras oncogene-transformed NIH/3T3 cells

We investigated the involvement of Rac1 in Ha-ras-overexpression-induced apoptosis using a murine NIH/3T3-derived cell line (designated 7-4), which contains an inducible Ha-ras oncogene under the regulation of Escherichia coli lac operator-repressor system. Ha-ras overexpression was induced by isopropyl beta-D-thiogalactoside (IPTG). To reveal the role of endogenous Rac1, the dominant negative Rac1(Asn17) gene was transfected into the 7-4 cells. Using two cell lines 7-4 Racd2 and 7-4 Racd3 (7-4 derivates) stably expressing Rac1(Asn17), we demonstrate that suppression of Rac1 activity blocked Ha-ras-overexpression-induced apoptosis under a serum-depleted condition, indicating that Rac1 activity is required for a Ras-mediated apoptosis pathway. Cell-cycle analysis revealed that dominant-negative Rac1 partially shifted cell population from S-phase to G0/G1 phase in the cells overexpressing Ha-ras. In contrast to other reports, we showed activation of the transcription factor NFkappaB in the two cell lines expressing dominant-negative Rac1. All together, our results demonstrate that Ha-ras-overexpression- induced apoptosis can be blocked by dominant-negative Rac1, possibly through decreased S-phase accumulation and increased NFkappaB activity.

Direct regulation of insulin secretion by angiotensin II in human islets of Langerhans

AIMS/HYPOTHESIS

This study aimed to identify the expression of angiotensin II receptors in isolated human islets and beta cells and to examine the functional consequences of their activation.

MATERIALS AND METHODS

Single-cell RT-PCR was used to identify whether human islet cells express mRNA for type 1 angiotensin II receptors (AT(1)), and western blotting was used to determine AT(1) protein expression by human islets and MIN6 beta cells. We measured changes in intracellular calcium by microfluorimetry using Fura 2-loaded MIN6 cells and human islet cells. Dynamic insulin secretory responses were determined by RIA following perifusion of human islets and MIN6 cells.

RESULTS

Human islets expressed mRNAs for both the angiotensin precursor, angiotensinogen, and for angiotensin-converting enzyme. In addition, human and mouse beta cells expressed AT(1). These were functionally coupled to increases in intracellular calcium, which occurred at least in part through phospholipase-C-sensitive mechanisms and calcium influx through voltage-operated calcium channels. Short-term exposure of human islets and MIN6 cells to angiotensin II caused a rapid, short-lived initiation of insulin secretion at 2 mmol/l glucose and potentiation of insulin secretion induced by glucose (at 8 and 16.7 mmol/l).

CONCLUSIONS/INTERPRETATION

These data demonstrate that the AT(1) is expressed by beta cells and that angiotensin II effects a short-lived and direct stimulation of human and mouse beta cells to promote insulin secretion, most probably through elevations in intracellular calcium. Locally produced angiotensin II may be important in regulating a coordinated insulin secretory response from beta cells.

Enhanced transformation and chemosensitivity of NIH3T3 cells transduced with hepatoma up-regulated protein

Hepatoma up-regulated protein (HURP) is a recently identified novel cell-cycle-regulated gene. The HURP gene is overexpressed in human hepatocellular carcinoma and transitional cell carcinoma. The cellular function of HURP is not fully understood. In this study, the NIH3T3 cells transduced with the exogenous HURP gene manifested the general characteristics of tumor cells, which had higher growth rate in low-serum media and advanced ability of colony formation on agarose-based plates. Transduced HURP was capable of specifically enhancing the chemosensitivity of deoxycytosine analogs, such as gemcitabine, ARA-C, and 5-AZA-CdR, but neither had an effect on the response of DNA intercalating agents, such as cisplatin, carboplatin, and doxorubicin, nor on the response of microtubule stabilizers, such as paclitaxel, docetaxel, and vinblastine. These results indicate that the HURP gene might be a potential oncogenic gene and capable of enhancing the chemosensitivity of deoxycytosine analogs in NIH3T3 cells.

Aurora-A overexpression associates with Ha-ras codon-12 mutation and blackfoot disease endemic area in bladder cancer

Our data revealed that 59.4% of the bladder cancer specimens showed Aurora-A overexpression, of which 31.8% also had Ha-ras codon-12 mutation; 45.5% were from blackfoot-disease endemic areas in which arsenic exposure is a major environment factor associated with various cancer formation. We further demonstrated that arsenic treatment of the immortalized bladder cell line, E7, increased Aurora-A expression. All together, co-existence of Aurora-A overexpression and Ha-ras mutation suggests a possible additively effect on the tumorigenesis of bladder cancer. In addition, Aurora-A overexpression and up-regulated by arsenic exposure opens a new direction for exploring the occurrence of bladder cancer occurrence in Taiwan.

Primary and immortalised human pancreatic islet endothelial cells: phenotypic and immunological characterisation

AIMS/HYPOTHESIS

Studies on the biology of the microvascular endothelial cells (MECs) that surround and penetrate the pancreatic islets are hampered by difficulties in isolating and culturing large numbers of pure cells. We aimed to morphologically and functionally characterise primary MECs purified and cultured from human islets, and to establish a simian virus 40 (SV40)-immortalised cell line from these primary cultures.

MATERIALS AND METHODS

Human islet MECs were extracted and purified using anti-CD105 coated immunomagnetic beads, and endothelial markers and surface molecules analysed by flow cytometric analysis. An immortalised cell line was then established by using a chimeric adeno5/SV40 virus.

RESULTS

Islet MECs expressed classic and specific endothelial markers, a high basal level of intercellular adhesion molecule-1, and low levels of E-selectin and TNF (previously known as TNF-alpha) inducible vascular cell adhesion molecule-1. IFNG (previously known as IFN-gamma) induced expression of HLA class II molecules. The immortalised islet MECs expanded rapidly, exhibited increased DNA synthesis, and were passaged approximately 30 times, without signs of senescence. They retained the endothelial characteristics of the parental cells, and behaved as the primary cells in terms of TNF stimulation of expression of adhesion molecules and support of leucocyte adhesion and transmigration.

CONCLUSIONS/INTERPRETATION

The immortalised islet MECs that we have established could effectively represent a substitute for primary counterparts for in vitro studies on the role of the microvasculature in pathophysiological processes involved in type 1 and type 2 diabetes.

Insulin-producing cells derived from human pancreatic non-endocrine cell cultures reverse streptozotocin-induced hyperglycaemia in mice

AIMS/HYPOTHESIS

The aim of the study was to investigate the potential of human pancreatic non-endocrine cells to transdifferentiate into endocrine cells that would be capable of secreting insulin in response to glucose and ameliorating insulin-deficient diabetes after transplantation.

MATERIALS AND METHODS

Cell fractions enriched with exocrine cells after human islet isolation were treated with streptozotocin to remove residual beta cells, grown in monolayer culture to allow de-differentiation, transferred to cluster culture for redifferentiation in the presence of activin A, betacellulin, nicotinamide and glucose, supplemented with 10% FCS, and administered to streptozotocin-induced diabetic SCID mice. A subset of cells was transfected with the IPF1 gene (also known as PDX1) before transdifferentiation.

RESULTS

No insulin was detectable in cell preparations after 5 days of treatment with streptozotocin. In monolayer culture, 90% of the streptozotocin-treated pancreatic cells co-expressed cytokeratin-19 and vimentin at 2 weeks and 60% expressed nestin at 4 weeks. Cell cultures with a high proportion of nestin-expressing cells had greater plasticity for transdifferentiation into cells with phenotypic and functional markers of beta cells, this property being significantly enhanced by transfection with IPF1 gene and leading to 15+/-6.7% insulin-positive cells after transplantation vs. 0.01% of cells transplanted after streptozotocin treatment alone. These cells improved glucose control in all of 42 diabetic mice after transplantation, restoring normoglycaemia in 40%.

CONCLUSIONS/INTERPRETATION

Human pancreatic cells are a potential source of new glucose-responsive insulin-producing cells that may be developed further for clinical use.

Expression of nephrin by human pancreatic islet endothelial cells

AIMS/HYPOTHESIS

The islet microcirculation has morphological characteristics resembling those of renal glomeruli. Transcription of the nephrin gene, a highly specific barrier protein of the slit diaphragm of podocyte foot processes, has been reported in the pancreas, although its cellular localisation and function remain to be defined. In this study, we purified and characterised microvascular endothelial cells (MECs) isolated from human islets and investigated the expression and distribution of nephrin on these cells.

METHODS

Human islet MECs were extracted and purified using anti-CD105-coated immunomagnetic beads and their endothelial characteristics were confirmed by expression of classical endothelial markers and basal high-level expression of intercellular adhesion molecule-1 and TNF-alpha-inducible vascular cell adhesion molecule-1. Nephrin expression was assessed by immunofluorescence, flow cytometric analysis and western blotting on cell lysates, as well as by RT-PCR.

RESULTS

Immunofluorescence studies detected nephrin in a fine, punctate, diffuse pattern on cultured islet MECs, and also in human pancreatic islet sections. In both cases nephrin colocalised with endothelial markers. TNF-alpha treatment induced a marked reduction and redistribution of the protein in one or multiple aggregates. Nephrin expression was confirmed by flow cytometry, western blotting and RT-PCR studies. In contrast, nephrin could not be detected at the protein or mRNA level in human macro- and microvascular cells from other sites.

CONCLUSIONS/INTERPRETATION

Nephrin is expressed at protein and mRNA levels in islet microendothelium, supporting the hypothesis that islet MECs exhibit distinctive morphological characteristics that indicate functional specialisation of potential pathophysiological importance.

Bone marrow that is positive for Epstein-Barr virus encoded RNA-1 by in situ hybridization is related with a poor prognosis in patients with extranodal natural killer/T-cell lymphoma, nasal type

BACKGROUND AND OBJECTIVES

Extranodal NK/T-cell lymphoma, nasal type is an aggressive lymphoma that is always associated with Epstein-Barr virus (EBV). This study was done to evaluate the use of EBV-encoded RNA-1 in situ hybridization (EBER-1 ISH) to detect occult micrometastasis in the bone marrow (BM) of patients with nasal NK/T-cell lymphoma.

DESIGN AND METHODS

A total of 23 patients who underwent BM biopsy for routine pre-therapeutic evaluation were enrolled in the study. We used EBER-1 ISH to investigate the expression of EBER-1 in 30 BM specimens. The clinical correlation and therapeutic outcomes of these patients were analyzed. In addition, genomic analysis of EBV was performed in five patients.

RESULTS

Conventional morphologic examinations failed to identify any lymphoma involvement in the 23 BM specimens obtained at initial staging. However, 10 of the 23 BM were positive for EBER-1. A lower survival rate was seen in patients with BM positive for EBER-1. Only the BM EBER-1 ISH result was shown to be an independent variable predicting overall survival in stage I and II patients (p=0.027; hazard ratio for death 0.066, 95% confidence interval, 0.006 to 0.733), suggesting that EBER-1 positivity in BM is the major determinant of a poor prognosis. However, discrepancies in the EBV strains between the primary tumor and BM existed in two of the five studied patients.

INTERPRETATION AND CONCLUSIONS

We suggest that EBER-1 ISH should be performed on BM specimens of patients with nasal NK/T-cell lymphoma to identify the presence of EBER-1 positive cells, which appears to carry a poor prognosis. Whether or not the EBER-1 positive cells in the BM of nasal NK/T-cell lymphoma patients are true tumor cells requires further study.

Increased expression of matrix metalloproteinase-2 in oral cells after short-term stimulation and long-term usage of areca quid

BACKGROUND AND PURPOSE

Arecoline, an areca quid (AQ) component, has been shown to inhibit the secretion and activity of matrix metalloproteinase-2 (MMP-2) in fibroblast cultures. This study assessed whether MMP-2 expression was inhibited in the saliva samples and tumor specimens of oral tumor patients with a long-term history of AQ consumption. The net effect of crude AQ extract (AQE) on MMP-2 expression by oral cells was also investigated.

METHODS

Western blot analysis, zymography, and reverse transcriptase-polymerase chain reaction were used to detect MMP-2 protein and mRNA in saliva and tumor samples, as well as in the conditioned media (CM) of oral cell cultures.

RESULTS

The level of MMP-2 protein was significantly higher in the saliva samples of 12 oral tumor patients who had a minimum 10-year AQ-consuming history than in those of 12 non-AQ-using healthy controls (p < 0.05). MMP-2 mRNA was expressed in 26 of 28 oral squamous cell carcinoma (OSCC) specimens. MMP-2 protein was also detectable in the tested OSCC homogenates. Short-term stimulation with 10% AQE increased the secretion of MMP-2 protein in the CM of oral epidermoid carcinoma cell Meng-1 (an OSCC cell line) and oral fibroblasts.

CONCLUSIONS

MMP-2 expression is elevated rather than inhibited in most oral tumor patients with long-term AQ usage. Short-term AQE stimulation also increases the secretion of MMP-2 by oral epithelial cells and fibroblasts. Our results suggest that AQ consumption may promote oral tumor progression through the induction of MMP-2 secretion.

Antitumor effects of zerumbone from Zingiber zerumbet in P-388D1 cells in vitro and in vivo

The fresh rhizome of Zingiber zerumbet (L.) Roscoe ex Smith (Zingiberaceae) is widely used as a folk medicine in Taiwan. In this study, the fresh rhizome was extracted with 95 % EtOH and partitioned with diethyl ether. The antitumor effects of the diethyl ether extract were measured in cultured P-388D (1) cells and in an animal model of P-388D (1)-bearing CDF (1) mice. The results indicated that the extract could induce DNA fragmentation in P-388D (1) cells in vitro, and significantly prolong the life of P-388D (1)-bearing CDF (1) mice (ILS% = 127.8) at a dosage of 5 mg/kg body weight. After column chromatography combined with an MTT cytotoxicity bioassay, zerumbone, a cyclic sesquiterpene was isolated from the diethyl ether extract. Zerumbone inhibited the growth of P-388D (1) cells, induced DNA fragmentation in culture, and significantly prolonged the life of P-388D (1)-bearing CDF (1) mice (ILS% = 120.5) at a dosage of 2 mg/kg. Furthermore, zerumbone inhibited the growth of a human leukemia cell line, HL-60 cells, in a time- and concentration-dependent manner, with IC (50) values of 22.29, 9.12, and 2.27 microg/mL for 6, 12, and 18 h, respectively. The cell cycle of HL-60 cells was observed after treatment with zerumbone, which induced G (2)/M cell cycle arrest in HL-60 cells in a time- and concentration-dependent manner, and decreased the cyclin B1/cdk 1 protein level. These results suggest that zerumbone is an active principal of Z. zerumbet and is potentially a lead compound for the development of anticancer drugs.

Areca quid chewing enhances the expression of salivary matrix metalloproteinase-9

BACKGROUND AND PURPOSE

The effects of areca quid (AQ) consumption on salivary matrix metalloproteinases (MMPs) which may participate in tumor invasion and metastasis remains unclear. This study assessed the change in salivary MMP-9 protein levels 2 hours after 5-minute AQ chewing stimulation (AQCS) in non-AQ users and the expression profile of this proteinase in saliva and tumor specimens of oral squamous cell carcinoma (OSCC) patients with a history of AQ use.

METHODS

MMP-9 transcript was analyzed by reverse transcription-polymerase chain reaction. MMP-9 protein level was measured by both Western blot and gelatin zymography.

RESULTS

The protein level of salivary MMP-9 was 3.1- to 8.9-fold enhanced 2 h after AQCS in 3 healthy volunteers as revealed by Western blot and zymography. As a control, gum chewing did not significantly change salivary MMP-9 protein level. Expression of MMP-9 transcript was found in 25 of 28 OSCC specimens and significantly correlated with cervical lymph node metastasis (p = 0.037). All of the 8 tested OSCC tissue homogenate samples available and all 12 saliva samples from 12 oral tumor outpatients were positive for MMP-9 protein.

CONCLUSIONS

Elevation of MMP-9 may be one of the net effects of AQCS in vivo, which may play a role in the pathogenesis of oral mucosal lesions. Furthermore, the association of MMP-9 expression with neck-lymph-node metastasis may imply a significant role of MMP-9 in the progression of OSCC among patients with a history of AQ use in Taiwan.

The synergistic cytotoxicity of cisplatin and taxol in killing oral squamous cell carcinoma

BACKGROUND

Platinum, 5-fluorouracil (5-FU) and taxanes are commonly used in chemotherapeutic modalities of various carcinomas. However, taxanes are rarely used in patients suffering from head and neck squamous cell carcinoma (HNSCC) in Taiwan. The purpose of this study was to assess whether there is a synergistic effect produced by incorporating Taxol (paclitaxel) with cisplatin, carboplatin or 5-FU in the combined treatment of oral squamous cell carcinoma (OSCC).

METHODS

OSCC cells were surgically excised from a Taiwanese patient and cultured into a cell line, OECM-1. The viability of OECM-1 after drug treatment was determined by an XTT labeling reagent.

RESULTS

The dose-dependent cytotoxicity of each drug was determined. The order of chemosensitivity of OECM-1 toward these drugs was Taxol, cisplatin, carboplatin and 5-FU, with 50% inhibitory concentrations (IC(50)s) of 10, 68, 332 and 3000 microM, respectively. In the combined drug treatment, low concentrations of platinum (10 microM) or 5-FU (500 microM) were included in the culture media with low cytotoxic concentrations of Taxol (0.025, 0.05 and 0.1 microM). When combined with 0.025 microM of Taxol, only cisplatin, rather than carboplatin and 5-FU, showed synergistic cytotoxicity with OECM-1. Cisplatin also acted synergistically with 0.05 and 0.1 microM of Taxol. On the other hand, carboplatin and 5-FU acted additively with low cytotoxic concentrations of Taxol (0.025, 0.05 and 0.1 microM).

CONCLUSIONS

Our preliminary results suggest that there may be a beneficial outcome in incorporating Taxol into the chemotherapeutic modalities of HNSCC patients in Taiwan. Furthermore, at least some of the OSCC cells may be more sensitive to Taxol/cisplatin than to Taxol/carboplatin or Taxol/5-FU treatment.

ACTH stimulates insulin secretion from MIN6 cells and primary mouse and human islets of Langerhans

It has previously been suggested that ACTH and ACTH-related peptides may act as paracrine modulators of insulin secretion in the islets of Langerhans. We have, therefore, examined the expression and function of the ACTH receptor (the melanocortin 2 receptor, MC2-R) in human and mouse primary islet tIssue and in the MIN6 mouse insulinoma cell line. Mouse MC2-R mRNA was detected in both MIN6 cells and mouse islet tIssue by PCR amplification of cDNA. In perifusion experiments with MIN6 pseudo-islets, a small, transient increase in insulin secretion was obtained when ACTH(1-24) (1 nM) was added to medium containing 2 mM glucose (control) but not when the medium glucose content was increased to 8 mM. Further investigations were performed using static incubations of MIN6 cell monolayers; ACTH(1-24) (1 pM-10 nM) provoked a concentration-dependent increase in insulin secretion from MIN6 monolayer cells that achieved statistical significance at concentrations of 1 and 10 nM (150 +/- 13.6% basal secretion; 187 +/- 14.9% basal secretion, P<0.01). Similar responses were obtained with ACTH(1-39). The phosphodiesterase inhibitor IBMX (100 microM) potentiated the responses to sub-maximal doses of ACTH(1-24). Two inhibitors of the protein kinase A (PKA) signaling pathway, Rp-cAMPS (500 microM) and H-89 (10 microM), abolished the insulin secretory response to ACTH(1-24) (0.5-10 nM). Treatment with 1 nM ACTH(1-24) caused a small, statistically significant increase in intracellular cAMP levels. Secretory responses of MIN6 cells to ACTH(1-24) were also influenced by changes in extracellular Ca2+ levels. Incubation in Ca2+-free buffer supplemented with 0.1 mM EGTA blocked the MIN6 cells' secretory response to 1 and 10 nM ACTH(1-24). Similar results were obtained when a Ca2+ channel blocker (nitrendipine, 10 microM) was added to the Ca2+-containing buffer. ACTH(1-24) also evoked an insulin secretory response from primary tIssues. The addition of ACTH(1-24) (0.5 nM) to perifusions of mouse islets induced a transient increase in insulin secretion at 8 mM glucose. Perifused human primary islets also showed a secretory response to ACTH(1-24) at basal glucose concentration (2 mM) with a rapid initial spike in insulin secretion followed by a decline to basal levels. Overall the results demonstrate that the MC2-R is expressed in beta-cells and suggest that activation of the receptor by ACTH initiates insulin secretion through the activation of PKA in association with Ca2+ influx into beta-cells.

Dominant negative knockout of p53 abolishes ErbB2-dependent apoptosis and permits growth acceleration in human breast cancer cells

We previously reported that the ErbB2 oncoprotein prolongs and amplifies growth factor signalling by impairing ligand-dependent downregulation of hetero-oligomerised epidermal growth factor receptors. Here we show that treatment of A431 cells with different epidermal growth factor receptor ligands can cause growth inhibition to an extent paralleling ErbB2 tyrosine phosphorylation. To determine whether such growth inhibition signifies an interaction between the cell cycle machinery and ErbB2-dependent alterations of cell signalling kinetics, we used MCF7 breast cancer cells (which express wild-type p53) to create transient and stable ErbB2 transfectants (MCF7-B2). Compared with parental cells, MCF7-B2 cells are characterised by upregulation of p53, p21(WAF) and Myc, downregulation of Bcl2, and apoptosis. In contrast, MCF7-B2 cells co-transfected with dominant negative p53 (MCF7-B2/Delta p53) exhibit reduced apoptosis and enhanced growth relative to both parental MCF7-B2 and control cells. These data imply that wild-type p53 limits survival of ErbB2-overexpressing breast cancer cells, and suggest that signals of varying length and/or intensity may evoke different cell outcomes depending upon the integrity of cell cycle control genes. We submit that acquisition of cell cycle control defects may play a permissive role in ErbB2 upregulation, and that the ErbB2 overexpression phenotype may in turn select for the survival of cells with p53 mutations or other tumour suppressor gene defects.

Bio-affecting mercury detection using mercury resistance gene module fused with bioluminescence reporter genes

Bioluminescence sensor systems were developed for monitoring environmental mercury contamination. The biological mercury measurement sensor systems were constructed by DNA recombination technique. A bacterial mercury-resistant operon (meroperon) from Pseudomonas sp. K-6y4 and a bacterial bioluminescence operon (lux operon) from an ocean bacterium Vibrio fischeri were fused in avector plasmid. The resulting recombinant plasmids were cloned in Escherichia coli cells. The bioluminescence sensor systems responded to mercury chloride of 0.1 nM to 100 nM. The mercury bioluminescence sensor developed in this study can be used for monitoring of the bio-affecting mercury instead of total mercury that is measured by conventional analytical equipment. The fundamental feature of the bioluminescence sensor system is attractive for use as a monitoring system for bio-affecting environmental mercury contamination.

Conformational adjustments of SNase R and its N-terminal fragments probed by monoclonal antibodies

Two monoclonal antibodies specific for staphylococcal nuclease R (SNase R) (McAb2C9 and McAb1B8) were prepared and used to probe protein folding during peptide elongation, by measuring antibody binding to seven N-terminal fragments (SNR141, SNR135, SNR121, SNR110, SNR102, SNR79 and SNR52) of SNase R. Comparative studies of the conformations of the N-terminal fragments have shown that all seven fragments of SNase R have a certain amount of residual structure, indicating that folding may occur during elongation of the nascent peptide chain. We show that the binding abilities of the intact enzyme and its seven fragments to the monoclonal antibodies are not simply proportional to the length of the peptide chain, suggesting that there may be continuous conformational adjustment in the nascent peptide chain as new C-terminal amino acids are added. A folding intermediate close in structure to the native state but with structural features in common with SNR121 is highly populated in 0.6 M GuHCl, and is also formed transiently during folding.

Multisite phosphotyping of the ErbB-2 oncoprotein in human breast cancer

BACKGROUND

Overexpression of the ErbB-2 (HER2/neu) receptor tyrosine kinase is one of the most common molecular changes in human cancer, but the functional significance of this phenotype remains uncertain.

METHODS AND RESULTS

Using phosphorylation-specific antibodies recognizing different ErbB-2 functional states, we assessed the phosphorylation status of ErbB-2 in 102 human breast cancer specimens. Quantitative ErbB-2 immunoblotting intensity correlated directly with that of immunohistochemistry (r = 0.84). Widely varying phosphorylation profiles were evident in 65 ErbB-2-positive carcinomas, suggesting different ErbB-2 functions in different tumors. In a subset of patients for whom clinical data were obtainable, mortality trends were strongly associated with the quantitative signal intensities of ErbB-2 phosphoantibodies (P < or =.02), but not with those of conventional antibodies to ErbB-2 (P = .147), epidermal growth factor receptor (P = .44), or phosphotyrosine (P = .94).

CONCLUSION

Although requiring corroboration in larger prospective clinical studies, these findings suggest that immunophenotyping using phosphorylation-specific antibodies may enable more accurate prediction of cancer behavior than is currently obtainable using conventional reagents.