A phase 1 dose-escalating study of pegylated recombinant human arginase 1 (Peg-rhArg1) in patients with advanced hepatocellular carcinoma.

BACKGROUND: Hepatocellular carcinoma (HCC) cells are auxotrophic for arginine, depletion of which leads to tumour regression. The current study evaluated safety, pharmacokinetics (PK)/ pharmacodynamics (PD) parameters, and potential anti-tumor activity of pegylated recombinant human arginase 1 (peg-rhArg1) in advanced HCC patients. METHODS: Eligibility criteria included advanced HCC with measurable lesions, Child-Pugh A or B, and adequate organ function. Initial single IV bolus was followed by weekly doses of peg-rhArgI escalated from 500 U/kg to 2500 U/kg in a 3 + 3 design. RESULTS: Fifteen patients were enrolled at weekly doses of 500 U/kg (n = 3), 1000 U/kg (n = 3), 1600 U/kg (n = 3) and 2500 U/kg (n = 6). The median age was 57 years (33-74); 87% were hepatitis B carriers and 47% had prior systemic treatment. The most commonly reported drug-related non-haematological adverse events (AEs) were diarrhea (13.3%), abdominal discomfort (6.7%) and nausea (6.7%). No drug-related haematological AEs were seen. Only 1 of the six patients that received 2500U/kg peg-rhArg1 experienced DLT (grade 4 bilirubin elevation) and thus the maximum tolerated dose was 2500 U/kg. PK and PD analysis indicated that peg-rhArg1 was efficacious in inducing arginine depletion in a dose-dependent manner. Adequate arginine depletion dose was achieved in the 1,600-2,500 U/kg range and therefore the optimal biological dose was at 1600 U/kg, which was chosen as the recommended dose. The best response was stable disease for >8 weeks in 26.7% of the enrolled patients. CONCLUSION: Peg-rhArg1 has manageable safety profile and preliminary evidence of activity in advanced HCC patients.

Recombinant human arginase inhibits proliferation of human hepatocellular carcinoma by inducing cell cycle arrest.

Human hepatocellular carcinoma (HCC) has an elevated requirement for arginine in vitro, and pegylated recombinant human arginase I (rhArg-PEG), an arginine-depleting enzyme, can inhibit the growth of arginine-dependent tumors. While supplementation of the culture medium with ornithine failed to rescue Hep3B cells from growth inhibition induced by rhArg-PEG, citrulline successfully restored cell growth. The data support the roles previously proposed for ornithine transcarbamylase (OTC) in the arginine auxotrophy and rhArg-PEG sensitivity of HCC cells. Expression profiling of argininosuccinate synthetase (ASS), argininosuccinate lyase (ASL) and OTC in 40 HCC tumor biopsy specimens predicted that 16 of the patients would be rhArg-sensitive, compared with 5 who would be sensitive to arginine deiminase (ADI), another arginine-depleting enzyme with anti-tumor activity. Furthermore, rhArg-PEG-mediated deprivation of arginine from the culture medium of different HCC cell lines produced cell cycle arrests at the G(2)/M or S phase, possibly mediated by transcriptional modulation of cyclins and/or cyclin dependent kinases (CDKs). Based on these results, together with further validation of the in vivo efficacy of rhArg-PEG against HCC, we propose that the application of rhArg-PEG alone or in combination with existing chemotherapeutic drugs may represent a specific and effective therapeutic strategy against HCC.

Remission of hepatocellular carcinoma with arginine depletion induced by systemic release of endogenous hepatic arginase due to transhepatic arterial embolisation, augmented by high-dose insulin: arginase as a potential drug candidate for hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) is auxotrophic for the semi-essential amino acid arginine, depletion of which leads to tumor death. In humans, arginine is not an essential amino acid since many adult somatic cells can re-synthesize it from other sources, such as citrulline. Enzymes capable of depleting arginine in vitro include the urea cycle enzyme arginase, which is found in abundance in human liver. For over three decades, arginase has not been considered as a potential drug candidate because of its low substrate affinity, short circulatory half-life and sub-optimal enzymatic activity at physiological pH, though its in vitro anti-tumor activities in certain tumors have been amply reported. Arginine deiminase, a bacterial enzyme from Mycoplasma hominus has been shown to induce HCC remission through the mechanism of arginine depletion. We report here an innovative treatment approach for the treatment of locally advanced and metastatic HCC with transhepatic arterial embolisation (TAE) of the liver tumor with lipiodol and gel foam as a means of inducing a leakage of hepatic arginase from the liver into the circulation. Hepatic arginase released into the systemic circulation rapidly depleted plasma arginine. High-dose insulin was included to induce a state of hypoaminoacidaemia to augment arginine depletion. With this protocol, we have treated seven patients with locally advanced and/or metastatic HCC. Five patients achieved arginine depletion, ranging from 0 to 20 microM (normal plasma level 100-120 microM); all had varying degrees of tumor remission in their primary tumors and extra-hepatic sites in the lymph nodes, lungs and bones, suggesting systemic anti-cancer effect of arginine depletion. The two non-responders did not show significant reduction in plasma arginine. Based on our findings, we propose that the urea cycle enzyme, arginase, is a good drug candidate for the treatment of HCC.

Comparison of a 6-month course peginterferon alpha-2b plus ribavirin and interferon alpha-2b plus ribavirin in treating Chinese patients with chronic hepatitis C in Taiwan.

Previous studies in Caucasian patients showed treatment of chronic hepatitis C with pegylated interferon/ribavirin was well tolerated, and produced a higher response rate especially in genotype 1 infections. However, it is unknown whether this conclusion can be extrapolated to patients with Chinese ethnic origin. A total of 153 patients with biopsy-proven chronic hepatitis C were randomly assigned to receive either weekly injection of peginterferon alpha-2b 1.5 mcg/kg plus oral ribavirin (1000 or 1200 mg/day, depending on body weight) (PEG group, n = 76) or 3 MU of interferon alpha-2b t.i.w. plus ribavirin (IFN group, n = 77) for 24 weeks. Sustained virological response (SVR) was defined as the sustained disappearance of serum hepatitis C virus (HCV) RNA at 24 weeks after the end of treatment by polymerase chain reaction assay. Baseline demographic, viral and histological characteristics were comparable between the two groups. Using an intent-to-treat analysis, HCV genotype 1 patients showed a significantly higher SVR in patients receiving PEG-IFN rather than IFN (65.8%vs 41.0%, P = 0.019), but no difference was found in genotype non-1 patients (PEG vs IFN: 68.4%vs 86.8%, P = 0.060). Genotype 1 patients (28.6%) in the PEG-IFN group relapsed, as compared with 52.9% in the IFN group (P = 0.040). Multivariate analyses showed early virological response at week 12 of therapy and genotype non-1 were significant predictors to SVR. As compared with the IFN group, patients receiving PEG-IFN had a significantly higher rate of discontinuation, dose reduction, fever, headache, insomnia, leucopenia and thrombocytopenia. In genotype 1 chronic hepatitis C Chinese patient, PEG-IFNalpha2b ribavirin had significantly better SVR and lower relapse rate when compared to IFN/ribavirin. Both regimens can be recommended for genotype non-1 chronic hepatitis C Chinese patients. However, a higher rate of adverse events and discontinuance of therapy were noted in patients treated with PEG-IFNalpha2b ribavirin.

Sclerosant extravasation as a complication of sclerosing endotherapy for bleeding gastric varices.

We report here the case of a 65-year-old woman who suffered intraperitoneal sclerosant leakage after endoscopic injection sclerotherapy for bleeding gastric varices. In total, 3 ml of N-butyl-2-cyanoacrylate and Lipiodol mixture was injected. The patient developed mild fever and pain over the left upper quadrant and flank after the procedure. In addition to a Lipiodol-filled gastric varix, the imaging studies disclosed a wide spread of Lipiodol over the left peritoneal cavity. The patient was kept fasting with parenteral antibiotics and nutrition. She responded well to the treatment, and all of the symptoms had subsided 6 days later.

GB virus-C/hepatitis G virus infection in a hepatitis C virus endemic village: prevalence in residents with low educational attainment and frequent recovery in females.

AIMS/BACKGROUND: GB virus-C/hepatitis G virus (HGV) is a newly identified flavivirus, which may share the same mode of transmission as hepatitis C virus (HCV). The aim of this study was to investigate associated factors of HGV infection and clearance in a HCV endemic village in southern Taiwan. METHODS: Five hundred and ninety-four residents of a village in southern Taiwan were enrolled for hepatitis virus screening. Clinical features were recorded and a questionnaire addressing the possible routes of transmission was filled in by the participating residents. RESULTS: The prevalence of antibody to hepatitis C virus and hepatitis B surface antigen in the 594 residents was 70.7% and 19.5% respectively. Of the 399 residents tested for HGV RNA, GB virus-C/Hepatitis G virus envelop 2 protein (HGV-E2) antibody, and HCV RNA, the prevalence was 13.5%, 25.3%, 53.1% respectively. Multivariate logistic regression analysis showed that low educational attainment was associated with HGV infection, old age and low educational attainment were associated with HCV infection, and female gender was associated with HGV clearance. Alanine aminotransferase (ALT) values were significantly higher for residents with HCV infection alone, HBV infection alone, and co-infection of HCV and HBV than for those without HBV, HCV, and HGV infection. There were no differences in ALT values between subjects with HGV infection alone and those without HBV, HCV, and HGV infections. Residents with co-infection of HGV and HBV, or HGV and HCV had ALT values similar to those with HBV or HCV infection alone. CONCLUSION: HGV infection is common in the HCV endemic village. The transmission of HGV is closely related to low educational attainment. HGV clearance is frequently encountered in females. Co-infection of HGV does not compound hepatocellular inflammation.

Failure to confirm major objective antitumor activity for streptozocin and doxorubicin in the treatment of patients with advanced islet cell carcinoma.

BACKGROUND: The combination regimen of streptozocin plus doxorubicin is the current standard chemotherapeutic treatment of symptomatic or progressing metastatic islet cell carcinoma. This regimen previously has been reported to have a major objective response rate of 69% in a randomized cooperative group trial. However, the authors believed that this favorable response rate was not consistent with their institutional experience at Memorial Sloan-Kettering Cancer Center (MSKCC). METHODS: The authors retrospectively reviewed the records of all islet cell carcinoma patients under care at MSKCC who were treated with streptozocin plus doxorubicin since the publication of the study mentioned earlier. Sixteen such patients treated between February 1992 and February 1998 were identified. Their clinical characteristics, sites of measurable disease, response to treatment, time to treatment failure, and survival status were reviewed. RESULTS: All patients were treated with the starting doses as outlined by the published cooperative group report. All had bidimensionally measurable disease on computed tomography (CT) scans. Only 1 of 16 patients (6%; 95% confidence interval, 0-30%) achieved a major objective response by standard CT response criteria, with response ongoing during treatment at 18 months. Nine patients (56%) had stable disease while receiving treatment (range of treatment, 2-17+ months). Six patients (38%) had progression of disease as their best response while receiving treatment. The median overall survival of this patient group had not yet been reached at last follow-up, with > 60% of patients alive with follow-up ranging from 10-67+ months. CONCLUSIONS: A retrospective analysis of the authors' 6-year experience with the combination of streptozocin plus doxorubicin in patients with islet cell carcinoma failed to confirm the high objective response rate previously reported for this regimen. There remains an urgent need for improved chemotherapeutic alternatives for patients with this disease.

Clinical assessment of the bacterial load of Helicobacter pylori on gastric mucosa by a new multi-scaled rapid urease test.

The present study tests the efficacy of the multi-scaled urease test (MUT) in detecting Helicobacter pylori infection and determines whether the MUT can predict the bacterial density on histology. A total of 111 sets of gastric specimens were obtained from patients with dyspepsia but without recent bleeding. Two biopsies were taken as closely as possible in each set. One sample was used for the MUT (Hp fast; GI Supply, Camp Hill, PA, USA), while the other was used to determine the histological density of H. pylori by modified Giemsa stain (grade 0-5). The results of MUT were interpreted as negative if the colour was yellow or bright green (reaction score 0) and positive if the colour was green, light blue, or blue (reaction score 1, 2 and 3, respectively). The reaction scores of MUT were recorded sequentially at 15 and 30 min and 1, 4 and 24 h. On the basis of histological confirmation, MUT had a sensitivity of 89.6%, a specificity of 88.2%, a positive predictive value of 94.5% and a negative predictive value of 78.9%. Focusing on specimens with the presence of bacteria under histology, 77 specimens were divided into five subgroups by grades of density of H. pylori (HPD1-5). The reaction scores had become sequentially elevated from 30 min through to 24 h in each subgroup. For subgroups HPD4 and 5, the positive rates of MUT were 70.6 and 66.6%, respectively, as early as 30 min and progressed to 100% within 4 h. In contrast, the positive rate for the HPD1 subgroup was 16.6% at 4 h and increased to only 62.5% at 24 h. In subgroups HPD 2 and 3, the positive rates were less than 30% at 30 min, but became more than 66.6% at 4 h and were 100% at 24 h. The early (i.e. mean value of reaction scores before 4 h) and late (24 h) mean reaction scores disclosed two elevated trends as the density of H. pylori increased (early: 0.2, 0.7, 0.8, 1.5, 1.2; late: 1.4, 2.3, 2.6, 3.0, 3.0; P < 0.05). In conclusion, MUT is a reliable method for the diagnosis of H. pylori infection. It can also indirectly predict the density of H. pylori on histology.

Hepatic adenoma: an observation from asymptomatic stage to rupture.

A 39 year old female, who took oral contraceptives for about ten years, was found to have an asymptomatic hepatic adenoma during an episode of acute hyperlipidemic pancreatitis. The diagnosis was confirmed by sonography, CT scan, angiography, and liver biopsy. She refused operation and was followed at the outpatient clinic. Initially, the tumor decreased its size after withdrawal of oral contraceptives, but enlarged again on subsequent examinations. She came back to emergency room with hemoperitoneum and intratumoral hemorrhage eighteen months after the initial diagnosis. Her hepatic adenoma was removed surgically and was found to be ruptured. She has been well for two years.

Immunohistological characteristics of the infiltrating lymphoid cells and expression of HLA class I and II antigens in nasopharyngeal carcinoma.

The immunohistological characteristics of infiltrating lymphoid cells and the expression of human leucocyte antigens class I and II (HLA-ABC and HLA-DR, respectively) were studied in 50 pre-treatment nasopharyngeal carcinomas. The majority of lymphoid cells were activated lymphocytes expressing thymocyte OKT10 marker. CD4+ cells (T-helper/inducer) out-numbered CD8+ cells (T-suppressor/cytotoxic) by at least two- to four-fold. CD22+ cells (pan-B lymphocytes) were scanty in the peri-tumoral areas and were absent in 29 out of 50 biopsies. A moderate number of cells expressing CD15 (monocytes/macrophages) were also detected. CD16+ cells (natural killer cells) were found to be sparse or absent. Expression of HLA class I and II antigens on the tumor cells in 35 biopsies was variable. HLA-ABC staining was intense in 6, reduced in 13 and partially lost in 16, whereas staining of HLA DR was intense in 7, reduced in 11 and partially lost in 17. Full expression of both antigens was demonstrable in only 2 biopsy samples. The expression of HLA antigens in the tumour had no relationship to the type or degree of lymphocytic infiltration or staging of the tumour.

Megakaryoblastic transformation of a myeloproliferative disorder.

A case of megakaryoblastic transformation of a myeloproliferative disorder presenting initially as chronic granulocytic leukaemia with an intermediate phase of essential thrombocythaemia in a Chinese woman of 65 years is reported. The diagnosis of megakaryoblastic crisis was based on morphological, cytochemical and immunocytochemical features present in blast cells in the blood, together with cytochemical and ultrastructural features of micromegakaryocytes and megakaryoblasts which were predominant in the marrow. A literature review showed newer refinements in diagnosis such as ultrastructural platelet peroxidase and additional immunologic techniques employing antisera against further platelet products. The response to treatment remains uniformly poor.

Lymphopenia and deranged lymphocyte subsets in nasopharyngeal carcinoma.

The peripheral blood lymphocyte counts of 333 patients with a nasopharyngeal carcinoma and 125 control subjects were compared. The mean pretreatment lymphocyte count in the patients was significantly lower than that of the normal controls (P less than 0.0001). Subgroup analysis of absolute lymphocyte counts in different stages of the disease revealed a stage dependent lymphopenia which became significant when the disease was stage III or over (P less than 0.001). Characterization of peripheral blood lymphocyte subsets in 81 patients and 46 normal control subjects revealed a significant reduction of the absolute Pan T (T11) lymphocytes in the patients (P less than 0.0001). Both the absolute numbers of T helper (T4) and suppressor cells (T8) were reduced in the patients (P less than 0.0001 and less than 0.026, respectively). While the percentage of T4 was reduced (P less than 0.0001), the percentage of T8 was elevated (P less than 0.02), resulting in a reduced T4/T8 ratio (P less than 0.0001). The mean absolute and percentage counts of T11, T8 and B did not correlate with different stages of the disease.

Acute lymphoblastic leukemia in Chinese adults in Hong Kong.

Forty-four previously untreated Chinese adult patients with acute lymphoblastic leukemia (ALL) were treated with vincristine, adriamycin and prednisone with or without L-asparaginase. The clinical features and prognostic factors were similar to those reported in Caucasian series. Overall complete remission (CR) rate was 52%. Duration of first remission and overall median survival were nine and 12 months respectively. The addition of L-asparaginase did not improve CR rate or duration of remission and was associated with clotting dysfunction and other adverse reactions. Factors associated with a higher CR rate include age less than 40 years, blast count less than 10 x 10(9)/l and CALLA + phenotype at presentation. Sex, platelet count and FAB morphology did not affect CR rate. Bone marrow relapse occurred in 11 patients and was associated with short survival after relapse (median two months; mean two months; range 0.5-7 months). Central nervous system relapse occurred in four patients and was compatible with relatively long survival after relapse (median 13 months; mean 12 months; range 6-12 + months). The poor CR rate and short median survival in this study could not be adequately explained by an increase in risk factors and is likely to be due to what is currently regarded as suboptimal chemotherapy.

A study of lymphocyte kinetics in nasopharyngeal carcinoma with indium III oxine-labelled lymphocytes.

The kinetics of lymphocyte migration in 12 pre-treatment patients with nasopharyngeal carcinoma (NPC) and three cancer controls in remission were studied with Indium III oxine-labelled autologous lymphocytes. The migratory patterns of the labelled lymphocytes were defined by serial gamma imaging and blood clearance of Indium over 72 h. Once in the systemic circulation the labelled lymphocytes migrated immediately to the liver and spleen. In all the subjects studied the lymphocytes began to migrate out of the liver at 0.5 h, only to return to the organ gradually between 2 and 72 h. In the control subjects the lymphocytes migrated out of the spleen from about 4 h. This coincided with a hump in the peripheral blood clearance curve after about 4 h signifying re-entry of the lymphocytes into the vascular space from the spleen. In the 'early' NPC subjects (Stage I-III) the rate at which the lymphocytes entered the spleen was much reduced from about 4 to 72 h, suggesting a prolonged transit time of the lymphocyte through the organ. However, there were still prominent humps in the blood clearance curves, suggesting significant re-entry of lymphocytes into the vascular space. In the 'late' NPC subjects (Stage IV-V), the activity of the spleen was low between 4 and 72 h and there was continuous sequestration of lymphocytes in the organ. Consequently the humps in the blood clearance curves were much reduced or absent. The activities of the metastatic lymph nodes were intense between 2 and 48 h, suggesting marked sequestration of lymphocytes in the diseased lymph nodes. Migration of lymphocytes in the metastatic area of the liver was notably absent and presented as cold areas on gamma scanning. The sequestration of lymphocytes in the spleen and metastatic lymph nodes in 'early' and 'late' NPC could lead to a contraction of intravascular lymphocyte pool and could explain the stage-dependent lymphopenia reported in NPC.

Peripheral blood lymphocyte subsets in nasopharyngeal carcinoma.

Peripheral blood lymphocyte subsets were studied in 29 untreated Chinese nasopharyngeal carcinoma (NPC) patients and 20 normal controls of similar age range and sex ratio with indirect immunofluorescence using monoclonal antibodies. The percentage T lymphocyte (T11) count, percentage and absolute T helper (T4) lymphocyte counts and the T helper/T suppressor-cytotoxic cell ratio (T4/T8) were significantly lower, while the percentage and absolute T8 counts were significantly higher in NPC patients. Concerning B lymphocytes, B1 cell count was normal while B4 cell count (B lymphocytes including early B lymphocytes) was significantly lower in NPC patients. These various lymphocyte subset changes were not related to the clinical stage or to Epstein-Barr viral IgA viral capsid antibodies and IgA early antibodies. The pathogenetic and prognostic significance of peripheral blood lymphocyte changes in NPC requires further investigation.

Nasal T-cell lymphoma associated with hemophagocytic syndrome.

A patient with immunohistochemically confirmed nasal T-cell lymphoma is reported. He developed systemic histiocytosis with marked hemophagocytosis, simulating malignant histiocytosis. The differential diagnosis from the latter is discussed.