Phase I study of the anti-TIGIT antibody tiragolumab in combination with atezolizumab in Japanese patients with advanced or metastatic solid tumors

PURPOSE

Tiragolumab is a monoclonal antibody that binds to the inhibitory immune checkpoint TIGIT (T-cell immunoreceptor with Ig and ITIM domains). In early phase clinical trials, tiragolumab in combination with the programmed death-ligand 1-inhibitor atezolizumab was well tolerated and has demonstrated preliminary anti-tumor activity in patients with advanced/metastatic solid tumors. We report the results of a phase I study of tiragolumab plus atezolizumab in Japanese patients (jRCT2080224926).

METHODS

Japanese patients ≥ 20 years old received tiragolumab (600 mg) and atezolizumab (1200 mg) intravenously every 21 days until unacceptable toxicity or disease progression. Primary endpoints were safety and pharmacokinetic (PK) parameters of tiragolumab plus atezolizumab. Secondary endpoints were anti-tumor activity.

RESULTS

Three patients were enrolled with diagnoses of non-small cell lung cancer, pancreatic cancer, and cholangiocarcinoma. No dose-limiting toxicities were observed. Two patients experienced treatment-related adverse events (AEs) of any grade. There were no grade ≥ 3 AEs, serious AEs, AEs leading to discontinuation, modification or withdrawal of any study drug, or AEs leading to death. At cycle 1, mean PK parameters of tiragolumab were as follows: Cmax 217 μg/mL; Cmin 54.9 μg/mL; area under the concentration-time curve from 0 to the last measurable concentration, 2000 μg·day/mL; t1/2, 17.6 days. Best overall response was stable disease in two patients.

CONCLUSION

Tiragolumab plus atezolizumab was well tolerated in Japanese patients with advanced/metastatic solid tumors, and no differences in tiragolumab PK characteristics were noted between Japanese patients enrolled in this study, and non-Japanese patients enrolled in a global phase Ia/Ib study. These results may support the inclusion of Japanese patients in ongoing global phase III clinical trials.

TRIAL REGISTRATION NUMBER

jRCT2080224926.

Seeding Activity-Based Detection Uncovers the Different Release Mechanisms of Seed-Competent Tau Versus Inert Tau via Lysosomal Exocytosis

The pathological aggregation of tau characterizes a set of neurodegenerative diseases collectively referred to as tauopathies. Recent studies using cellular and animal models have suggested that tau pathology progresses by trans-cellular propagation. The process of propagation is mediated by certain species of extracellular tau, which are taken up by recipient cells and serve as a seed for tau aggregation. Tau propagation is currently one of the most active areas of research in dementia. Previous efforts to identify the specific tau molecules involved in propagation have suggested that multiple forms of tau with different molecular weights derived from recombinant tau or brain lysates exert seeding activity. Nonetheless, the molecular characteristics of the “extracellular” seed-competent tau as well as its release mechanisms remain to be elucidated. Given that tau is physiologically released into the extracellular space, it is critical to distinguish seed-competent tau from normal monomeric tau. Utilizing biosensor cells expressing P301S mutant tau fused to CFP/YFP, here we discriminated between seed-competent tau and inert monomer tau released from HEK293 cells. By analyzing the size-exclusion fractions of the media, we found that seed-competent tau was enriched in high molecular weight fractions of >2,000 kDa, while the majority of soluble tau in the media positively detected by ELISA was in low molecular weight fractions. We also found that lysosomal stress not only increased Ca²⁺-dependent release of seed-competent tau but also altered its molecular size. Inhibiting lysosomal exocytosis specifically decreased release of seed-competent tau without influencing total tau. These data underscore the differential response of seed-competent tau and inert tau to lysosomal stress and indicates the presence of distinct release mechanisms via lysosomes.

The Carboxyl-Terminal Half-Molecule of Ovotransferrin Prepared by Selective Digestion of the Amino-Terminal Lobe with Thermolysin

Diferric ovotransferrin was hydrolyzed by thermolysin, a thermostable protease, at elevated temperatures. At 65 degrees C, the amino(N)-terminal lobe was completely digested into small peptides, while the carboxyl(C)-terminal lobe was significantly resistant to the protease. This permitted the isolation of an iron-bound C-terminal half-molecule consisting of a glycosylated single polypeptide in an excellent yield (about 90%). The fragment comprises the residues from 336 to the C-terminus of ovotransferrin. The results for the visible absorption spectrum of the copper-bound fragment, the stability of the iron-bound fragment in high concentration of urea, and the CD spectra of the fragment in the far and near UV regions indicated that it retains the metal binding activity and conformation of the C-terminal lobe of intact ovotransferrin.

Clinical management of autoimmune pancreatitis

Autoimmune pancreatitis (AIP) is a newly described entity with characteristic clinical, radiological, serological, and histological features, in which autoimmune mechanisms seem to be involved in pathogenesis. Many new clinical aspects of AIP have been clarified during 10 years, and AIP has become a distinct entity recognized worldwide. However, precise pathogenesis or pathophysiology remains unclear. As AIP responds dramatically to steroid therapy, accurate diagnosis of AIP is necessary to avoid unnecessary laparotomy or pancreatic resection. It is importance to misdiagnose pancreatic cancer as AIP as well as to misdiagnose AIP as pancreatic cancer. In the absence of a diagnostic serological marker for AIP, its diagnosis rests on identifying unique patterns of abnormalities. Japanese criteria are based on the minimum consensus features of AIP and aim to avoid misdiagnosis of malignancy. It contain 3 items: (1) enlargement of the pancreas and narrowing of the main pancreatic duct; (2) high serum gammaglobulin, IgG, or IgG4, or the presence of autoantibodies; (3) histological findings of lymphoplasmacytic infiltration and fibrosis in the pancreas. For diagnosing AIP, the presence of the imaging criterion is essential. Other clinical characteristics of AIP are elderly male preponderance, fluctuating obstructive jaundice without pain, occasional association with diabetes mellitus and extrapancreatic lesions, and favorite responsiveness to oral steroid therapy. Elevation of serum IgG4 levels and infiltration of abundant IgG4-positive plasma cells in various organs are rather specific in AIP patients. In an elderly male presenting obstructive jaundice and pancreatic mass, AIP should be considered as one of differential diagnoses.

Three-dimensional images for surgical plan of giant sacral schwannoma

OBJECTIVE

Documentation of three-dimensional (3D) images of a giant sacral schwannoma with intrapelvic expansion.

SETTING

Nagoya University, Nagoya, Japan.

RESULTS

3D computed tomography (3D CT) showed a destructed bony region clearly. 3D CT angiography clarified the positional relationship between tumor and iliac arteries. Resection procedure was safely completed based on these 3D evaluations.

CONCLUSION

3D images were helpful to make a surgical plan and to complete this complicated resection combined with sacroiliac reconstruction.

Immunohistochemical detection of 8-hydroxydeoxyguanosine, a marker of oxidative DNA damage, in human chronic cholecystitis

AIMS

Recent studies suggest that oxidative DNA damage induced during chronic inflammation may play a role in carcinogenesis in some organs. Although gallbladder carcinomas are frequently observed with a background of chronic cholecystitis, little is known about oxidative DNA damage in chronic cholecystitis. The aims of this study were to investigate the expression of 8-hydroxydeoxyguanosine (8-OHdG), a biomarker of oxidative DNA damage, in normal and chronically inflamed human gallbladder mucosa and compare its expression with clinicopathological findings.

METHODS AND RESULTS

8-OHdG expression was immunohistochemically examined using a monoclonal antibody against 8-OHdG in human gallbladder specimens. In normal gallbladder (n=5), no 8-OHdG expression was observed. In contrast, nuclear expression of 8-OHdG was detected in 28 of 31cases (90.3%) in gallbladder epithelial cells with chronic cholecystitis. The positive cells were predominantly observed in the areas of active inflammation with prominent cell infiltration. Quantitative analysis revealed that the number of 8-OHdG+ cells (labelling index) significantly (rs=0.671, P < 0.05) correlated with the degree of the activity of mucosal inflammation, while gender, age, and the presence of gallstones did not influence the index.

CONCLUSIONS

Oxidative DNA damage is common in chronic cholecystitis, suggesting a possible link between chronic inflammation and gallbladder carcinogenesis.

Reduced expression of p16 and p27 proteins in nasopharyngeal carcinoma

Nasopharyngeal carcinoma (NPC) is a malignant tumor with a high incidence in east Asian countries. Inactivation of cyclin-dependent kinase (CDK) inhibitors (CKIs) and overexpression of G1 cyclin has been thought to be important for tumor development. To determine whether reduction of CKI (p16 and p27) expression was associated with NPC development, we performed immunohistochemical staining of NPC specimens from 20 patients. We found that p16 and p27 proteins were negative in 8 of 20 and 16 of 20 cases, respectively; that either p16 or p27 proteins were negative in 17 of 20; and that both p16 and p27 were negative in 7 of 20. Excepting the cases in which both CKIs were negative, negativity of p27 alone was statistically higher than that of p16 (9/20 versus 1/20, P = .022), suggesting that the reduction of p27 protein is an important event for the multi-step process of NPC development.

Mapping airborne lead contamination near a metals smelter in Derbyshire, UK: spatial variation of Pb concentration and 'enrichment factor' for tree bark

Samples of tree bark, collected over an area of 4 km2 near a small non-ferrous metals smelter in Derbyshire, UK, were analysed for Pb and Al by inductively coupled plasma atomic emission spectroscopy (ICP-AES). Analyte concentrations varied from 100 to over 25,000 mg kg-1 and 5 to 1000 mg kg-1, respectively. While an inverse relationship between the Pb content of bark and distance from the smelter was observed, concentrations fluctuated, indicating a variability in sample collection efficiency and problems in standardization. To overcome these effects, the Pb/Al ratio was calculated and subsequently normalized to the average Pb/Al ratio in continental crust (0.00015). On the assumption that the time-averaged concentration of airborne Al in this area is relatively constant and derived principally from wind-blown soil, the measurement represents an anthropogenic 'enrichment factor' (PbEF). PbEF varied from 10,000 to over 1,000,000, and showed a consistent reduction with distance from the smelter. Isolines of equal PbEF were subsequently defined on a map of the sampled area. Pb contamination was greatest in the vicinity of the smelter, and preferential transport along the NW-SE axis of the valley (in which the smelter is situated) was observed. The use of enrichment factors thus proved valuable in defining the relative level of airborne-derived Pb pollution.

[A case of breast cancer 5 cm in diameter treated with a breast preserving approach after preoperative intra-arterial chemotherapy]

The patient was a 59-year-old female with a mass in the right breast (area C). At the initial examination, the mass was 5.0 x 4.5 cm on palpation, aspiration cytology was Class V, and a diagnosis of T2aN1aM0, Stage II breast cancer was made. Since the patient strongly desired a breast preserving treatment, a reduction in the size of the mass was attempted by local intra-arterial chemotherapy. Docetaxel (TXT) was administered at 60 mg into the internal thoracic artery and lateral thoracic artery at a rate of once a month for a total of 5 times. After the fifth treatment, the mass was reduced in size to 2.8 x 2.5 cm on palpation, and breast-preserving resection was then carried out. On histopathological examination, cancer was observed in an area of 3.0 x 2.2 cm. Careful follow-up is still needed, but preoperative intra-arterial chemotherapy is considered to be significant as a step before breast preserving surgery for breast cancer with a diameter of 3-5 cm.

Airborne uranium contamination--as revealed through elemental and isotopic analysis of tree bark

A new strategy for characterisation of airborne uranium contamination based on ICP mass spectrometric analysis of tree bark is described. The uranium content of tree barks (50 samples) obtained from diverse locations (remote, rural, industrial) varied over almost four orders of magnitude (0.001-8.3 micrograms/g U) with maximum concentrations recorded in the vicinity of a nuclear fuel fabrication plant (0.70-8.3 micrograms/g U). Elevated concentrations were also observed near a coal-fired power station (0.25-0.38 microgram/g U). Isotopic analysis revealed significant deviation from the natural uranium isotope ratio (235U/238U, 0.00725) at four nuclear installations (235U/238U, 0.0055-0.0097). These findings indicate that tree bark serves as an effective biomonitor for uranium and, with isotopic analysis, discrimination between nuclear and non-nuclear emissions is realised.

The potential of elemental and isotopic analysis of tree bark for discriminating sources of airborne lead contamination in the UK

Samples of tree bark, which accumulate airborne material, were collected from seven locations in the UK to provide an indication of the magnitude and source of lead pollution. Measurement of the Pb content and 206/207Pb stable isotope ratio by inductively coupled plasma mass spectrometry revealed significant differences between the sites. The concentration of Pb varied over almost four orders of magnitude from 7.2 to 9,600 micrograms g-1, the maximum values being found near a 'secondary' Pb smelter. The 206/207Pb isotope ratios varied from 1.108 +/- 0.002 to 1.169 +/- 0.001. The lowest Pb concentrations and highest isotope ratios were detected in bark samples from the Scilly Isles, reflecting the low-level of industry and road traffic. In contrast, samples obtained from a city centre (Sheffield) and near a motorway (M1) contained 25-46 micrograms g-1 Pb and recorded the lowest 206/207Pb ratios. Higher concentrations in the vicinity of a coal-fired power station recorded a 206/207Pb ratio of 1.14, suggesting a significant contribution from fly-ash. The relative contribution of lead from petrol (206/207Pb = 1.08) and other sources such as coal (206/207Pb = 1.18) were thus estimated using mass balance equations. Tree bark near the lead smelter recorded an intermediate 206/207Pb ratio of 1.13 reflecting the processing of material of mixed origin.

Nitric oxide via macrophage iNOS induces apoptosis following traumatic spinal cord injury

To investigate the pathophysiological mechanisms involved in post-traumatic impairment of the spinal cord, we analyzed expression patterns of the inducible nitric oxide synthase (iNOS) gene following acute injury of rat spinal cord using a weight drop technique. PCR analysis revealed that iNOS mRNA appeared at 3-12 h after injury and declined thereafter. Immunohistochemical analysis showed that iNOS-positive cells invaded the lesioned area through the perivascular space at 6 h after injury. The population of these cells peaked at 24 h and then declined to disappear 3 days after injury. The iNOS-positive cells were also stained with ED-2 but not with ED-1 or OX-42, indicating that these cells were macrophages and/or perivascular cells. In parallel with the appearance of iNOS-positive cells, other cells emerged that were positively stained by the terminal deoxynucleotidyl-transferase-mediated dUDP-biotin nick end-labeling (TUNEL) assay. TUNEL-positive cells were scattered in the lesioned area 1 day after injury, but some in the surrounding area close to iNOS-positive cells. Administration of L-Ng-nitro-arginine methylester, a competitive inhibitor of NOS, resulted in a reduction of TUNEL-positive cells in the lesioned area. These results suggest that nitric oxide generated by iNOS of macrophages and/or perivascular cells plays a significant role in eliminating damaged cells from the lesioned area by apoptosis.

Increase in neurotrophin-3 expression followed by Purkinje cell degeneration in the adult rat cerebellum after spinal cord transection

Changes in brain-derived neurotrophic factor (BDNF) and neurotrophin-3 (NT-3) contents following thoracic spinal cord transection were investigated in the cerebral cortex, hippocampus, and cerebellum of rats. The NT-3 content became significantly elevated at 3 days after transection only in the cerebellum and gradually declined to the control level by 6 days after the injury, remaining unchanged in the cerebral cortex and hippocampus. No significant change in the BDNF content was observed in any of the regions tested. Immunohistochemical analysis showed that the labeling indicating NT-3-like immunoreactivity was intensified in both cerebellar granule and Purkinje cells 3 days after the injury. The number of Purkinje cells with aggregation of chromatin around the nuclear membrane and swelling of the cytoplasm and/or organelles gradually increased with time starting 4 days after the injury, demonstrating morphological changes indicative of necrosis. However, no abnormal morphology was found in cerebellar granule cells at any time examined. We suggest that it is reasonable that increased NT-3 stimulated the death of Purkinje cells, because 1) the degeneration was necrosis, which is known to be accelerated by neurotrophins under certain pathological conditions, and 2) the increase in NT-3 occurred prior to Purkinje cell degeneration. Therefore, our present results may imply that spinal cord injury-induced NT-3 accelerates injury rather than alleviates degeneration of Purkinje cells.

Up-regulation of glial cell line-derived neurotrophic factor (GDNF) following traumatic spinal cord injury

We investigated the temporal and spatial expression patterns of the GDNF gene after subjecting rats to an acute contusion injury of the spinal cord using the weight drop technique. Reverse transcriptase-polymerase chain reaction (RT-PCR) revealed that GDNF transcription in the spinal cord began to increase within 30 min after injury and peaked within 3 h. Immunohistochemical analysis showed GDNF immunoreactivity to be present mainly in microglia and macrophages 1 day after injury, but not in neurons or astrocytes. This immediate upregulation of GDNF gene expression may be a component of an inflammatory process and probably exerts a protective effect on neurons following spinal cord injury (SCI).

An experimental model of tumor dormancy therapy for advanced head and neck carcinoma

An experimental model of tumor dormancy therapy for advanced head and neck carcinoma was developed. After transplantation of KB cells into nude mice, the mice were given tiracoxib, a selective cyclooxygenase (COX)-2 inhibitor, probucol, an antioxidant, and S-1, an oral pro-drug of 5-fluorouracil (5-FU), or combinations of two of them. The combined administration of tiracoxib with probucol significantly inhibited the tumor growth. The angiogenesis in this group was markedly reduced. Tiracoxib and probucol did not affect the intratumoral concentration of 5-FU when coadministered with S-1. The combined use of tiracoxib and probucol is thus a candidate for use in maintenance therapy after the primary therapy for patients with advanced head and neck carcinoma.

Therapeutic effect of 1 M tegafur-0.4 M 5-chloro-2, 4-dihydroxypridine-1 M potassium oxonate (S-1) on head and neck squamous carcinoma cells

1 M Tegafur (FT)-0.4 M 5-chloro-2,4-dihydroxypridine (CHDP)-1 M potassium oxonate (Oxo) (S-1), was developed as a new oral antineoplastic agent based on biochemical modulation of fluorouracil (5-FU) by CHDP and Oxo. The antitumor effect of S-1 on human head and neck squamous carcinoma cells was evaluated in xenografts and a metastasis model, in comparison with combined drug of 1 M FT and 4 M uracil (UFT). Mice treatment with S-1 showed a significant higher concentration of 5-FU in the tumor and the serum than UFT treated mice. S-1 showed higher tumor growth inhibition and metastasis inhibition than UFT. The mice in which metastasis was inhibited lived more than twice as long as the control mice. These results suggest that S-1 will have a higher clinical therapeutic effect against advanced squamous cell carcinoma of the head and neck in humans.

Therapeutic effects of loxiglumide on experimental acute pancreatitis using various models

We investigated the therapeutic effects of a cholecystokinin A (CCK-A) receptor antagonist, loxiglumide, on various models of experimental pancreatitis. This study shows that loxiglumide ameliorated caerulein-induced acute pancreatitis in mice as previously reported. The effects of loxiglumide on hemorrhagic and necrotizing acute pancreatitis is controversial. This study, however, shows that loxiglumide improves the survival rates in necrotizing acute pancreatitis induced by intraductal injection of taurocholate, followed by caerulein injection. In addition, the administration of loxiglumide improved both the biochemical and pathological changes of edematous acute pancreatitis induced by a closed duodenal loop in rats. It is concluded that the CCK-A receptor antagonist, loxiglumide, has therapeutic and/or prophylactic effects on acute pancreatitis in various models of experimental acute pancreatitis.

Clinical evaluation of cholecystokinin-A- receptor antagonist (loxiglumide) for the treatment of acute pancreatitis. A preliminary clinical trial. Study Group of Loxiglumide in Japan

The therapeutic effects of loxiglumide on human acute pancreatitis was investigated in 104 Japanese institutes from October 1992 to March 1994. Acute pancreatitis was diagnosed by the Japanese Criteria of Acute Pancreatitis. Soon after the diagnosis was made, one of three doses of loxiglumide (100, 300 and 500 mg/day) were injected intravenously twice a day for 14 days. The efficacy of the treatment was evaluated by clinical signs, physical signs, and biochemical findings. 189 patients were included in this trial. The clinical signs, such as abdominal pain, disappeared in 20% of the patients on the 1st day after treatment, and the rate of improvements increased thereafter. Physical signs also improved. Serum amylase levels returned to normal within 3 days after treatment, and serum lipase showed almost the same changes as serum amylase levels, but serum lipase levels in the high-dose group (500 mg/day) returned to normal more quickly compared with the other two doses. It is concluded that the cholecystokinin A receptor antagonist, loxiglumide, may become a useful drug in the treatment of acute pancreatitis in man, although more detailed investigations are needed.

Neuroendocrine carcinoma of the sigmoid colon: report of a case

Neuroendocrine carcinoma of the colon is a rare entity; however, this type of tumor is known for its aggressive progression and poor prognosis. A case of a 56-year-old Japanese male is presented in this report. A huge, child's head-sized tumor was found to have grown extraluminally on the sigmoid colon with multiple liver metastases. The tumor measured 16.5 x 15 x 8.2 cm in size and weighed 1 300 g. The patient died of hepatic failure due to massive liver metastases 6 months after operation. The pathological findings including an electron microscopic analysis were correlated with those of neuroendocrine carcinoma. We reviewed the English literature, and analyzed 94 cases of neuroendocrine carcinoma which had been reported previously. The nomenclature and definition of this disease still remains somewhat unclear, and not a small population of this disease may thus have been misdiagnosed and treated as other less aggressive entities. The necessity to make an accurate differential diagnosis in such cases is thus emphasized.

Chemiluminescence properties of soybean protein fraction in the hydroperoxide and hydrogen donor system

Whey fraction, a constituent of soybean protein, produced a photon emission in the presence of gallic acid and hydrogen peroxide. Identification of the chemiluminescence agent from the whey fraction indicated the participation of lipoxygenase in the emission. The reactivity of lipoxygenase with peroxides in the gallic acid solidus hydroperoxide system was in the order of methylethyl hydroperoxide (MEK-OOH, 4800 cps) > tert-butyl hydroperoxide (tert-BuOOH, 607 cps) > hydrogen peroxide (H(2)O(2), 455 cps) > cumene hydroperoxide (cumene-OOH, 261 cps). Emission maxima for H(2)O(2) and cumene-OOH were 670 nm, and emission maxima for MEK-OOH and tert-BuOOH were at 510 nm. The photon intensity from the gallic acid lipoxygenase system corresponded to the linoleic acid hydroperoxide value. A high correlation of photon intensity with hydroperoxide, including linoleic hydroperoxide was useful as a simple and sensitive method for the direct detection of hydroperoxides in biomaterials.

Establishment and characteristics of human hepatocellular carcinoma cells with metastasis to lymph nodes

BACKGROUND/AIMS

Although the mechanism of cancer metastasis has been gradually elucidated, less is known concerning the characteristics of human hepatocellular carcinomas (HCCs) with metastatic potential. We examined the expression of molecules that mediate cell-cell or cell-substrate interaction, nm23-H1 expression, and ultrastructural features of several human HCC cell lines.

METHODOLOGY

Expression of E-cadherin, integrin (alpha3beta1), intracellular adhesion molecule-1 (ICAM-1), and nm23-H1 protein was analyzed by immunocytochemistry or Western blotting, and ultrastructural features were further studied by electron microscopy in 4 human HCC cell lines, PLC/PRF/5, HuH-7, OCUH-16, and Nuk-1 which were originally established from metastatic cells in lymph nodes at our institute.

RESULTS

Neither E-cadherin, integrin, nor ICAM-1 was immunocytochemically detected in any of the 4 cell lines. Expression of nm23-H1 protein was weakly detected in OCUH-16, Nuk-1, and Huh-7 cells by Western blotting, but was clearly detected in PLC/PRF/5 cells by Western blotting. Ultrastructurally, metastatic Nuk-1 cells exhibited the intracytoplasmic canaliculus-like structures found in fibrolamellar carcinoma and the intracytoplasmic glandular lumina found in bile-duct carcinoma, while the other 3 cell lines did not. In addition, Nuk-1 cells expressed neither cytokeratin 8 nor cytokeratin 19.

CONCLUSIONS

Nuk-1 cells, which are human HCC cells with metastasis to lymph nodes, alone exhibited intracytoplasmic canaliculus-like structures and glandular lumina, as well as a marked reduction of nm23-H1 protein, but did not express E-cadherin, integrin, or ICAM-1. Formation of both intracytoplasmic canaliculus-like structures and intracytoplasmic glandular lumina is one of the characteristics that may be involved in metastasis of HCC cells to lymph nodes, as is reduction of nm23-H1 protein.

Homeless patients with hepatocellular carcinoma in Osaka City, Japan

BACKGROUND/AIMS

Although the number of homeless persons is increasing worldwide, studies delineating the health status of these persons according to various medical perspectives, including hepatology, are limited. However, such studies are important for understanding the pathogenesis of diseases and their prevention.

METHODOLOGY

Thirty homeless patients with hepatocellular carcinoma (HCC) and 15 with liver cirrhosis (LC) who were admitted to the Osaka Socio Medical center Hospital during the past 6 years were analyzed clinicopathologically. All were from the Airin district of Osaka City.

RESULTS

The patients with HCC had a history of long stay (mean: 25 years) in the district and many infectious opportunities and most of them were malnourished. The main causes of liver disease in the patients with HCC were hepatitis C virus (HCV) (77%), alcohol abuse (73%), and the combination of HCV and alcohol abuse (50%). Serum HCV RNA concentration was 10(5.8 +/- 0.9) copies/50 microliters in the 21 HCC patients and 10(6.5 +/- 0.7) copies/50 microliters in the 14 LC patients (p < 0.02). Six HCC patients (20%) were positive for the GB virus C/Hepatitis G virus (GBV-C/HGV) RNA in association with HCV or hepatitis B virus (HBV). Only 2 patients with HCC underwent the curative operations and most of the HCC cases were in progressed stages.

CONCLUSIONS

A long stay in a hygiene-poor environment increases the opportunity for infection in homeless people. The causative agents in the HCC and LC patients were mostly HCV, alcohol abuse, and a combination of the two. Since the quantification of HCV-RNA in the HCC patients was lower, the high level of HCV-RNA may not be a risk factor for the development of HCC. GBV-C/HGV may not also. The reversion to former healthy living conditions and reduction in alcohol consumption as soon as possible may contribute to low incidence of HCC and save the tax dollar expenditures among homeless people.

Insulinoma with hyperproinsulinemia during hypoglycemia and loss of expression of vacuolar-type H(+)-ATPase (V-ATPase) in the tumor tissue

Hypoglycemia with a low serum immunoreactive insulin (IRI) level and serum immunoreactive C-peptide (IRC) level was found in a 74-yr-old female. Although a fasting test induced hypoglycemia, the responses of IRI and IRC during the fasting test, and the results of a glucose tolerance test, glucagon test, and secretin test did not indicate the presence of an insulinoma. However, the serum proinsulin level before the fasting test was 130.5 pmol/L (N: 3.0-10.0 pmol/L), and this high level was maintained throughout the test. Soon after surgical enucleation of the tumor, the patient's blood glucose levels increased. Postoperatively, the hypoglycemic status resolved, and the serum proinsulin levels returned to normal (2.8 pmol/L). Histopathological studies revealed a typical insulinoma. Immunohistochemical studies by the recently developed method for vacuolar-type H+ (V-ATPase), which is responsible for acidification of the intracellular compartments in eukaryotic cells, showed that normal islets stained positive, but not the tumor. This finding indicates that the insulin-secretory granules in the insulinoma cells existed in a microenvironment in which V-ATPase activity had been lost. This suggests that the reduced activity of V-ATPase on the endomembrane of the insulin-secretory granules in insulinomas may result in loss of the acidic microenvironment and impaired conversion of proinsulin by converting enzymes.

Granular cell tumor of the duodenum: a case report

Granular cell tumor (GCT) in the duodenum is an extremely rare disease: only one case has been listed in a review, to date. We reported a 47-yr-old Japanese male case with GCT of the duodenum. Clinically, melena caused by bleeding from the tumor was the only symptom. The tumor cells showed abundant, granular eosinophilic cytoplasm. Although this tumor was clinically and histologically benign, highly developed tumor microvessels were demonstrated both angiographically and histologically, suggesting malignant potential of the tumor.

Polymorphisms of thymidine kinase gene in herpes simplex virus type 1: analysis of clinical isolates from herpetic keratitis patients and laboratory strains

Drug-resistance of herpes simplex virus (HSV) is caused most frequently by mutation of the viral thymidine kinase (TK) gene. To elucidate the significance of detecting nucleotide changes of the TK gene for screening drug-resistant viruses, the frequency and variation of the genetic polymorphisms in the whole coding region of the TK gene were studied in 14 acyclovir-susceptible HSV type 1 (HSV-1) clinical isolates from 14 patients with epithelial herpetic keratitis. Two reference HSV-1 laboratory strains, McKrae and PH, and two acyclovir-resistant variants of the PH strain were also studied as controls. Polymerase chain reaction-single-strand conformation polymorphism (PCR-SSCP) and direct sequencing detected nucleotide differences at 24 positions, and amino acid substitutions at 12 codons in the TK gene of the examined viruses. Nucleotide diversity of 0.0029 per base (the average number of nucleotide substitutions of 3.3 per 1,131 base pairs) in the TK gene in the clinical isolates was comparable to 0.0037 per base of the whole HSV-1 genome in Japanese isolates reported previously. PCR-SSCP analysis of the acyclovir-resistant strains easily detected aberrantly shifted bands by comparing them with those of the parental strain, followed by the quick determination of mutated sequences. These results suggest that detection of nucleotide changes of the TK gene is useful for serial observation of persistent or recurrent HSV infection as observed in immunocompromised hosts, but that it is not useful for screening drug-resistant viruses from nonepidemic clinical isolates because of the comparable genetic polymorphisms in the TK gene as in the whole HSV-1 genome.

Effect of electrical stimulation of the thalamic Vim nucleus on hand tremor during stereotactic thalamotomy

OBJECTIVE

The aim of this study was to analyze the correlation between neuronal responses in the thalamic ventralis intermedius (Vim) nucleus to peripheral, natural stimulation and the modulation of tremor by electrical stimulation during stereotactic thalamotomy.

DESIGN AND METHODS

The authors studied 36 patients with hand tremor using a microelectrode. The responses of tremor to electrical stimulation were analysed electromyographically. Sixty stimulation sites were divided into three groups.

RESULTS

Group A (20 sites) where responses to stretching of the contralateral forearm muscles were recorded. Group B (26 sites) where responses to stretching of the other muscles of the upper extremity were recorded. Electrical stimulation at sites in groups A and B temporarily suppressed the contralateral tremor, but the minimum current intensity to suppress tremor at sites in group A was less than that in group B. Electrical stimulation in group C (14 sites), where kinesthetic responses of contralateral lower extremity were recorded, resulted in increased amplitude of hand tremor. Selective coagulation including the area of tremor suppression resulted in abolition of the tremor in all patients.

CONCLUSIONS

These results suggest that the most effective site for thalamotomy may also be suitable for chronic stimulation in the Vim nucleus.

[5-fluorouracil and low-dose leucovorin as surgical adjuvant therapy from viewpoint of long-term outcome]

Biochemical modulation of 5-FU by leucovorin (LV) has been demonstrated to increase the therapeutic effect compared to single agent 5-FU in the treatment of patients (pts) with advanced colorectal cancer. The purpose of this study was to determine the effectiveness of the 5-FU + LV combination as adjuvant therapy following surgery in pts with Dukes' B, C colon cancer. Pts were entered in a stratified clinical trial comparing two different combination chemotherapeutic regimens to single agent 5-FU, given orally as a control. This report summarized the result of treatment in 61 pts who were 5-FU oral alone and 32 pts who were 5-FU (375 mg/m2) and low-dose LV (20 mg/m2) intravenously for 5 days with 5-FU oral intake. 5-FU with LV regimen was associated with an improved survival compared with the single agent 5-FU oral intake (p < 0.05). 5-FU with LV regimen resulted in less recurrence in liver and lung compared with single-agent 5-FU oral intake.

Pancreatic surgery in Japan: historical review

The advent of surgical techniques for the management of pancreatic cancer has had a long and varied history in the Western culture. The development of current surgical techniques and treatment modalities is based on (rooted in) techniques developed over time. Although the first written anecdotes of pancreatic resection--primarily from the 1600s through the late 1800s--did not alter the mortality of pancreatic cancer, they did pave the way for advances in surgical techniques that subsequently attained lower morbidity and mortality rates. Although there were some meager attempts at pancreatic resection in Japanese institutions before and during World War II, it was not until after the war, and particularly after the mid-1950s, that pancreatic surgery developed tremendously. The development of more radical approaches to pancreatic surgery developed tremendously. The development of more radical approaches to pancreatic resection as well as other surgical developments resulted in lower morbidity and mortality rates.

A new model for pancreatitis

Pancreatitis induced by ligation of the pancreatic duct produces morphologic similarities to human pancreatitis. This model is easily performed in big animals, but it is very difficult to perform pancreatic duct ligation in small animals. Many experimental studies of pharmaceutical treatments for pancreatitis used pancreatic duct-ligation models, but it is also difficult to evaluate the efficacy of the drugs used, because the animals used are of different species with individual differences. To overcome these problems, we ligated the main pancreatic duct of the splenic lobe by a 5.0 absorbable suture by using a surgical microscope and left the gastroduodenal lobe intact in the same rats. This model produced damaged pancreatic tissue in one part and normal pancreatic tissue in another part of the pancreas in the same animals, biochemically and histologically. We evaluated the effect of a new protease inhibitor (ONO-3404) on this preliminary model and found this new protease inhibitor demonstrated a hypertrophic effect on the damaged pancreatic tissue and the normal pancreatic tissue in the same animals. This model is also useful to study pharmaceutic treatment for pancreatic insufficiency and to study chemically induced pancreatic carcinogenesis in the damaged pancreatic tissue and the normal pancreatic tissue in the same animals.

Relaxant effects of NKH477, a new water-soluble forskolin derivative, on guinea-pig tracheal smooth muscle: the role of Ca2+-activated K+ channels

1. Mechanisms underlying the bronchorelaxant action of NKH477, a newly developed water-soluble forskolin derivative, were investigated in guinea-pig isolated tracheal smooth muscle. 2. In muscles precontracted with 3 microM histamine, NKH477 (1 nM-1 microM) caused a concentration-dependent decrease of isometric tension, resulting in a complete relaxation at 300 nM. The EC550 for the relaxation was 32.6+/-4.3 nM (n=6). 3. In the presence of 30 or 90 nM iberiotoxin (IbTX), a selective blocker of the large-conductance Ca2+-activated K+ (BK(Ca)) channel, the relaxing action of NKH477 on the histamine-induced contraction was inhibited, giving rise to a parallel shift of the concentration-response curves; the EC50 of NKH477 was increased to 131.4+/-20.4 nM at 30 nM IbTX (n=4), and 125.3+/-12.2 nM at 90 nM IbTX (n=4). 4. Pretreatment of muscles with 30 mM tetraethylammonium (TEA) caused a similar rightward shift of the concentration-response curve to NKH477 with an increase of the EC50 to 139.8+/-18.4 nM (n=5). In contrast, the relaxing action of NKH477 was unaffected by 10 microM glibenclamide, an ATP-sensitive K channel blocker, or by 100 nM apamin, a blocker of small conductance Ca2+-activated K+ channels. 5. In muscles pretreated with 1 microM nifedipine, a blocker of the voltage-dependent Ca2+ channel (VDC), 30-90 nM IbTX did not affect the relaxant effects of NKH477 on the histamine-induced contraction. 6. In muscles precontracted by a K+-rich (40 mM) solution, NKH477 caused only minimal relaxation (19.8+/-1.7%, n=4) even at the highest concentration (1 microM). 7. In experiments to measure the ratio of fura-2 fluorescence signals (R(340/380)) as an index of the intracellular Ca2+ concentration ([Ca2+]i), the application of 100 nM NKH477 or 200 nM isoprenaline to the preparation precontracted by 3 microM histamine resulted in a decrease in [Ca2+]i in association with a decrease in tension. The reduction of [Ca2+]i and tension by NKH477 was 47.0+/-5.6% and 62.8+/-7.0%, respectively (n=5), and that with isoprenaline 60.6+/-7.4% and 67.4+/-6.4%, respectively (n=5). These effects of NKH477 and isoprenaline on [Ca2+]i and tension were inhibited by 30 nM IbTX. The inhibitory action of IbTX was abolished in the presence of 1 microM nifedipine. 8. These results suggest that the bronchorelaxant action of NKH477 may result, at least in part, from activation of BK(Ca) channels, which may cause a hyperpolarization of smooth muscle cell membranes and a secondary decrease in Ca2+ influx through VDCs, leading to a decrease in [Ca2+]i.

Inhibitory effect of green tea extract on the process of pancreatic carcinogenesis induced by N-nitrosobis-(2-oxypropyl)amine (BOP) and on tumor promotion after transplantation of N-nitrosobis-(2-hydroxypropyl)amine (BHP)-induced pancreatic cancer in Syrian hamsters

Epidemiologic studies have shown a lower risk of gastrointestinal cancer in green tea drinkers. In the present study, the inhibitory effect of green tea extract (GTE) on the process of pancreatic carcinogenesis induced by N-nitrosobis-(2-oxypropyl)amine (BOP) and on tumor promotion after transplantation of N-nitrosobis-(2-hydroxypropyl)amine (BHP)-induced pancreatic cancer were investigated in hamsters. In the first experiment, shortly after the initiation of pancreatic carcinogenesis by BOP, the animals in the GTE group were given GTE (0.5 mg/L) in their drinking water and the control group was given tap water. All animals were sacrificed 24 weeks later. There were no significant differences in body weight, water intake, or food consumption between the two groups during the experiments. GTE consumption was approximately 1.25 mg/day/100 g body weight during this experiment. Seven of the 13 hamsters (54%) in the control group were found to have pancreatic tumors, versus six of the 18 hamsters (33%) in the GTE group. The average number of tumors in the control group was 1.0/hamster, compared with 0.5/hamster in the GTE group. The overall incidence of macroscopic pancreatic tumors in the GTE group was about half that in the control group. The incidence of pancreatic cancer was 54% (12/13) in the control group and 44% (8/18) in the GTE group. The number of pancreatic cancers, including invasive carcinoma and carcinoma in situ, in the GTE group was 0.88/hamster, significantly lower than in the control group (1.68/hamster) (p < 0.05). The incidence of atypical ductal hyperplasia, which is thought to be an early pancreatic cancer, was also significantly lower in the GTE group than in the control group (1.50/hamster vs. 4.65/hamster) (p < 0.05). In the second experiment, 1-mm3 pieces of BHP-induced pancreatic cancer were transplanted into the back of hamsters. The control group (N = 16) was maintained on the basal diet and tap water throughout the experiment, and the GTE group (N = 16) was also maintained on the basal diet and tap water for the first 3 weeks after transplantation, when successful transplantation was confirmed and, thereafter, given tap water containing GTE (0.5 mg/L) for an additional 12 weeks. Tumor growth was similar in both groups until 11 weeks after transplantation, but inhibition of tumor growth became apparent after 11 weeks in the GTE group. At 13 weeks, the average tumor volume in the GTE group was 1.01 +/- 0.11 x 104 mm3, significantly smaller than that in the control group (1.98 +/- 0.37 x 104 mm3) (p < 0.05). The results demonstrated that GTE has an inhibitory effect on the process of pancreatic carcinogenesis and on tumor promotion of transplanted pancreatic cancer. These results suggest that GTE may come to serve as a chemopreventive and chemotherapeutic agent for pancreatic cancer.

Relation between severity of magnesium deficiency and frequency of anginal attacks in men with variant angina

OBJECTIVES

We evaluated whether the severity of magnesium deficiency was correlated with the frequency of attacks of variant angina.

BACKGROUND

Magnesium deficiency may be associated with the development of variant angina. However, the relation between the activity of variant angina and magnesium deficiency remains to be elucidated.

METHODS

We assessed the body magnesium status of 18 men with variant angina: Group 1 (> or = 4 attacks/week, n = 7) and Group 2 (< 4 attacks/week, n = 11). Concentrations of magnesium were determined in serum, urine, mononuclear cells and erythrocytes, and the 24-h magnesium retention rate was determined.

RESULTS

Group 1 showed a higher 24-h magnesium retention rate (mean +/- SEM 63.5 +/- 7.6% vs. 24.9 +/- 2.7%, p < 0.01) and a lower intracellular concentration of magnesium in mononuclear cells and erythrocytes than did Group 2 (respectively, 156.3 +/- 13.5 vs. 212.1 +/- 6.9 fg/cell, p < 0.01; and 3.5 +/- 0.5 vs. 5.2 +/- 0.4 fg/cell, p < 0.05), demonstrating the presence of magnesium deficiency in Group 1. The 24-h magnesium retention rate and intracellular concentrations of magnesium in mononuclear cells and erythrocytes correlated well with the frequency of anginal attacks (r = 0.78, p < 0.01; r = -0.78, p < 0.01; r = -0.62, p < 0.01, respectively) for all patients.

CONCLUSIONS

Data suggest that the magnesium status of men with variant angina is closely related to disease activity.

Amebic liver abscess

We report eight cases of amebic liver abscess. All patients were men, and four were homosexual. Five of the eight patients had syphilis, but the four homosexual patients who were tested for HIV infection were negative. Ultrasonography (US), with or without needle aspiration, is the best method for diagnosing amebic liver abscess, and the treatment of choice is US-guided needle aspiration of the abscess followed by metronidazole therapy. Complication by other sexually transmitted diseases is another important factor affecting the treatment of this disease.

Inhibitory effect of sarcophytol A on pancreatic carcinogenesis after initiation by N-nitrosobis(2-oxypropyl)amine in Syrian hamsters

Sarcophytol A (SaA), a cembrane-type diterpene, inhibits pancreatic carcinogenesis induced by N-nitrosobis(2-oxypropyl)amine (BOP) in hamsters. The experimental groups received two injections of BOP at 70 mg/kg dose, followed 2 weeks later by a 20 mg/kg dose injection, and were fed a basal diet or 0.01 and 0.05% SaA diets starting 1 week after the second injection of BOP. Control groups were injected with normal saline and fed the basal diet or the 0.05% SaA diet. All animals were killed 30 weeks after the start of the experiments. Seventeen BOP-treated hamsters fed the basal diet developed pancreatic tumors (77.3%) while only 12 of 21 hamsters fed the 0.01% SaA diet (57.1%) and 12 of 23 hamsters fed the 0.05% SaA diet (52.2%) developed pancreatic tumors. Pancreatic lesions included ductal hyperplasia, atypical ductal hyperplasia, and carcinoma in situ. Microscopic invasive carcinoma induced by BOP and the incidence of larger pancreatic tumors in hamsters were significantly higher in hamsters fed the basal diet than in hamsters fed the SaA diet (p < 0.05). The proliferating cell nuclear antigen (PCNA) labeling index of pancreatic carcinoma in BOP-treated hamsters fed the basal diet was 41.2 +/- 13.4%, whereas BOP-treated hamsters fed 0.01 and 0.05% SaA diets yielded PCNA indexes of 26.8 +/- 8.3 and 28.4 +/- 7.0%, respectively. k-ras mutation was detected in 40% of cancers in both groups. No pancreatic tumors developed in saline-treated groups, and no differences in body weights or histological findings in their organs, including the pancreas, were observed in either group. These findings suggest that SaA not only inhibits BOP-induced pancreatic carcinogenesis in hamsters, but also provides antipromotion and antiprogression effects on these tumors, even when SaA commences 1 week after the initiation of pancreatic carcinogenesis.

Role of endogenous and exogenous cholecystokinin in experimental acute pancreatitis induced in rats by the duodenal loop technique

The role of endogenous cholecystokinin (CCK) release and exogenous CCK-8 administration in the development and progression of acute pancreatitis and in the early recovery phase of acute pancreatitis were investigated in rats with closed duodenal loop (CDL)-induced pancreatitis. The subcutaneous injection of CCK-8 (2 micrograms/kg) stimulated a physiological level of pancreatic enzyme secretion in normal control rats, but did not lead to any biochemical or histological evidence of acute pancreatitis. A higher dose of CCK-8 (8 micrograms/kg), however, did produce both biochemical and histological evidence of acute pancreatitis in the normal control rats. When 2 micrograms/kg of CCK-8 was injected subcutaneously in rats 6 and 12 h after the creation of the CDL, neither the biochemical nor the histological findings of acute pancreatitis showed any progression compared with the changes in controls given no CCK-8. Serum CCK levels, measured by radio-immunoassay, increased significantly from mean levels of 5.39 pg/ml (+/- 0.95 SD) before creation of the CDL to 42.06 pg/ml (+/- 2.27 SD) 6 h after, and 41.95 pg/ml (+/- 1.88 SD) 12 h after its creation (P < 0.01). The difference between serum CCK levels at 6 and 12 h was not statistically significant. Following the release of the loop, serum CCK levels decreased gradually, especially in rats in which the loop was released 6 h after being created. Although no marked biochemical and histological changes of acute pancreatitis were observed following the administration of 2 micrograms/kg of CCK-8 to rats upon release of the loop 6 h and 12 h after its creation, a higher dose of CCK-8 (8 micrograms/kg) in these rats adversely affected both the biochemical and histological findings of acute pancreatitis. Based on these findings, it was concluded that neither endogenous CCK release, as a result of the CDL, nor physiological stimulation of the pancreas by exogenous CCK-8 administration, caused progression from edematous to hemorrhagic acute pancreatitis, and neither CCK treatment had any adverse effect on the early recovery phase of CDL-induced acute pancreatitis. A pharmacological dose of CCK, however, exacerbated the acute pancreatitis, even in the early recovery stage.

Effects of a new synthetic lipid A on endogenous tumor necrosis factor production and antitumor activity against human pancreatic cancer cells

The effects of a synthetic lipid A on tumor necrosis factor (TNF) production and antitumor activity against human pancreatic cancer cells were investigated. Lipid A (10 mg/kg) was injected into normal rats and mice and serum TNF levels were measured. Lipid A-induced inhibition of Molt 4 and MIA paca-2 cells in culture were measured by counting viable cells. Activity of lipid A against transplanted human pancreatic cancer cells (MIA paca-2, Panc-1) was examined by determining tumor volume, necrosis, and survival rate after intraperitoneal injections of lipid A (10 and 20 mg/kg) over 4 weeks. Serum TNF levels increased 80-fold in rats and 100-fold in mice after intravenous lipid A injection. Although specific tumor growth inhibition by lipid A was not observed in vitro, tumor growth was significantly inhibited, and the survival rate was improved in pancreatic cancer cell-transplanted nude mice treated with lipid A compared with controls. Synthetic lipid A induces TNF production and has antitumor activity against transplanted pancreatic cancer cells. Further studies of this lipid A as an agent for pancreatic cancer are warranted.

Effects of bradykinin receptor antagonist on the release of beta-endorphin and bradykinin and on hemodynamic changes in a canine model of experimental acute pancreatitis

Bradykinin and beta-endorphin increases during acute pancreatitis are thought to contribute to the development of hypotension and myocardial depression in acute pancreatitis. beta-Endorphin release is mediated by trypsin-like enzymes and bradykinin from the pituitary gland. This study was undertaken to investigate the effect of a long-acting bradykinin receptor antagonist on bradykinin and beta-endorphin release and on hemodynamic changes during acute pancreatitis. Pancreatitis was induced by the injection of autologous bile mixed with trypsin into the main pancreatic duct after ligation of the accessory duct. Serum bradykinin and plasma beta-endorphin levels and cardiovascular function were measured. Twelve dogs (control group) were given 10 ml/kg/h of lactate Ringer's solution intravenously beginning 1 h before the induction of pancreatitis and continuing throughout the experiments. Six dogs received an intravenous infusion of 0.6 mg/kg/h of a new bradykinin receptor antagonist, HOE 140, D-Arg-[Hyp3, Thi5, D-Tic, Oic8]-bradykinin, in lactate Ringer's solution soon after the induction of pancreatitis. Six of twelve dogs in the control group, and none of the six dogs in the bradykinin receptor antagonist group, died during the experiments. Serum bradykinin levels in both groups increased until 1 h after the induction of pancreatitis, but thereafter the levels in the bradykinin receptor antagonist group decreased gradually until 5 h after induction, and levels were significantly lower than those in the control group (p < 0.05). Plasma beta-endorphin levels in the control group increased significantly, to 291.8 pg/ml (+/- 6.6 SEM) 5 h after the induction of pancreatitis, from the mean levels of 47.8 pg/ml before the induction of pancreatitis, while the mean beta-endorphin level in the bradykinin receptor antagonist group did not increase after the induction of pancreatitis. Infusion of the bradykinin receptor antagonist improved survival rates, hypotension, myocardial depression, and plasma lactate, suggesting that the bradykinin receptor antagonist inhibited the release of bradykinin and beta-endorphin, which contributed to the clinical improvement.