Successful management of malignant colovesical fistula using covered colonic self-expanding metallic stent: a case report

BACKGROUND

A colovesical fistula (CVF) is commonly treated by resection of the intestine containing the fistula or creation of a defunctioning stoma. We herein report a case of successful fistula closure and avoidance of colostomy after placement of a covered colonic self-expanding metallic stent (SEMS) as a palliative treatment for a malignant CVF.

CASE PRESENTATION

A 75-year-old man undergoing infusional 5-fluorouracil and irinotecan chemotherapy plus bevacizumab for recurrent peritoneal dissemination of rectal cancer was admitted to our hospital because of fecaluria with a high-grade fever. Blood tests showed a moderate inflammatory reaction (white blood cell count, 9200/mm3; C-reactive protein, 11.03 mg/dL; procalcitonin, 1.33 ng/mL). Urinary sediment examination showed severe bacteriuria. Abdominal contrast-enhanced computed tomography showed intravesical gas, thickening of the posterior wall of the bladder, and irregular thickening of the sigmoid colon wall contiguous with the posterior bladder wall. Magnetic resonance imaging (MRI) clearly showed a fistula between the bladder and sigmoid colon. Colonoscopy revealed a circumferential malignant stricture 15 cm from the anal verge, and a fistula to the bladder was identified by water-soluble contrast medium. We diagnosed a complicated urinary tract infection (UTI) associated with a CVF due to peritoneal dissemination and started empirical treatment with sulbactam/ampicillin. Given the absence of active inflammatory findings around the fistula on MRI and the patient's physical frailty, we decided to place a covered SEMS to close the fistula. Under fluoroscopic and endoscopic guidance, a covered colonic SEMS of 80-mm length and 20-mm diameter was successfully deployed, and the fistula was sealed immediately after placement. Urine culture on day 3 after stenting was negative for bacteria, and a contrast study on day 5 showed no fistula. The patient was discharged home on day 6 with no complications. The UTI did not recur for 4 months after discharge.

CONCLUSIONS

A covered colonic SEMS was useful for sealing a malignant CVF in a patient unfit for surgery, and MRI was valuable to determine the status of the fistula. A covered colonic SEMS could be an alternative to surgical treatment for CVFs in patients who require palliative care.

AB1330 AUTOMATIC SUBPIXEL MEASUREMENT OF RADIOGRAPHIC FINGER JOINT SPACE NARROWING IN RHEUMATOID ARTHRITIS PATIENTS UNDER TOCILIZUMAB TREATMENT

Background

The conventional scoring methods of radiographic joint space narrowing (JSN) in rheumatoid arthritis (RA) such as the Genant-modified Sharp score (GSS) are widely accepted but include subjective and time-consuming nature1. Therefore, we have developed an in-house software equipped with partial image phase-only correlation (PIPOC)2 which can automatically quantify joint space width (JSW) change.

Objectives

The purpose of this study was to investigate whether the in-house software can predict the inhibitory effect of tocilizumab on joint destruction in a short period of time.

Methods

The study included 39 RA patients (35 female) who were treated with tocilizumab (Table 1). Radiological progression of the metacarpophalangeal and the proximal interphalangeal joints was evaluated according to the GSS at 0, 6, and 12 months. Automatic measurement was performed by the in-house software (Figure 1). We then validated in-house software in terms of accuracy in detecting the JSN.

Figure 1.

The algorithm flow of in-house software equipped with PIPOC

Table 1.

Clinical characteristics of RA patients

variablebaseline6 months12 monthsTotal number of patients39Sex, female/male35/4Rheumatoid factor status, positive/negative29/10Age, mean (SD) years61.5 (14.6)Duration of disease, mean (SD) months111.4 (85.0)Swollen joint count, mean (SD)6.0 (4.7)3.5 (3.5)2.9 (4.0)Tender joint count, mean (SD)6.4 (3.5)2.9 (2.2)1.9 (2.0)DAS28-ESR, mean (SD)4.9 (1.2)3.0 (1.1)2.6 (1.0)DAS28-CRP, mean (SD)4.4 (1.1)3.0 (0.9)2.6 (0.8)

RA, rheumatoid arthritis; SD, standard deviation; DAS28, disease activity score with 28 joints; ESR, erythrocyte sedimentation rate; CRP, C-reactive protein

Results

To ensure homogeneity of the subjects, we targeted the joints with GSS = 0 at baseline in the software analysis. The success rate of the in-house software for JSW measurement was 96.8% (449/464). Here, the GSS (+)/PIPOC (+) were defined as joints with JSN progression according to the GSS and the software analysis, respectively. Otherwise, joints were defined as the GSS (-)/PIPOC (-) namely non-progressive JSN. The 0–12-month GSS with the 0–6-month GSS (+) group was significantly more JSN progression than the 0–6-month GSS (-) group (Mann-Whitney U test, p < 0.001). Similarly, the 0–12-month PIPOC with the 0–6-month PIPOC (+) group was significantly more JSN progression than the 0–6-month PIPOC (-) group (p < 0.001). The 0–12-month JSW change of finger joints with the 0–12-month GSS (+) detected by the in-house software was significantly greater than the 0–12-month GSS (-) (p = 0.02).

Conclusion

Our in-house software equipped with PIPOC might be able to predict the subsequent joint destruction with 6 months observations.

References

[1]Genant HK, et al: Assessment of rheumatoid arthritis using a modified scoring method on digitized and original radiographs. Arthritis & Rheumatism: Official Journal of the American College of Rheumatology 1998, 41(9):1583-1590.

[2]Ou Y, et al: Automatic Radiographic Quantification of Joint Space Narrowing Progression in Rheumatoid Arthritis Using POC. In: 2019 IEEE 16th International Symposium on Biomedical Imaging (ISBI 2019). 2019: 1183-1187.

Disclosure of Interests

Taichi Okino: None declared, Yafei Ou: None declared, Masayuki Ikebe: None declared, Akira Furusaki: None declared, Akira Sagawa: None declared, Masaru Kato: None declared, Tatsuya Atsumi: None declared, Tamotsu Kamishima Grant/research support from: Tamotsu Kamishima reports grants from Chugai Pharmaceutical.

A case of human breast sparganosis diagnosed as Spirometra Type I by molecular analysis in Japan

A 92-year-old Japanese woman presented with a mass in the left breast, and sparganosis was suspected by biopsy of the mass. The mass disappeared once, but it reappeared at the same site one year later. For a definitive diagnosis, the mass was surgically removed, and a sparganum-like worm was detected. The causative agent was confirmed as Spirometra Type I (most probably Spirometra mansoni) by mitochondrial DNA analysis. The serological examination also proved the case as sparganosis. Considering the presence of two Spirometra species (Type I and II) in Asia, particularly Japan, molecular analysis of the causative agents is highly recommended to understand the epidemiology, infection sources, and pathogenicity in humans in both species, if the parasite specimens are available.

How to treat remnant cholecystitis after subtotal cholecystectomy: two case reports

Background

Subtotal cholecystectomy in patients with severe acute cholecystitis is considered a “bailout” option when the safety of the bile duct cannot be guaranteed. However, subtotal cholecystectomy has a long-term risk of remnant cholecystitis. The appropriate management of remnant cholecystitis has not been fully elucidated.

Case presentation

Case 1 was a 66-year-old man who had undergone subtotal cholecystectomy 14 years prior to the development of remnant cholecystitis. We first performed endoscopic gallbladder drainage to minimize inflammation, and then proceeded with elective surgery. We performed a reconstituting procedure for the residual gallbladder due to significant adhesions between the cystic and common bile ducts. Case 2 was a 56-year-old man who had undergone subtotal cholecystectomy for abscess-forming perforated cholecystitis 2 years prior to the development of remnant cholecystitis. He underwent endoscopic drainage followed by complete remnant cholecystectomy 4 months later.

Conclusion

Endoscopic gallbladder drainage is a useful strategy to improve inflammation and reduce the risk of bile duct injury during remnant cholecystectomy.

Predictive model for postoperative pleural effusion after hepatectomy

AIM

Severe postoperative pleural effusion (sPOPE) after hepatectomy can lead to respiratory distress and may require thoracic drainage, leading to prolonged hospitalization. Preventive chest tube insertion may be useful for patients at high risk for sPOPE. We aimed to develop a predictive model for sPOPE after hepatectomy and evaluate indications for preventive chest tube insertion using our model.

METHODS

We evaluated all patients who underwent hepatectomy from 2013 to 2020. Risk factors for sPOPE were used to develop a predictive model for sPOPE, which was validated in a cohort that received preventative chest tube placement postoperatively.

RESULTS

A total of 325 patients were analyzed. Thirty-one (9.5%) patients had a preventive chest tube placed at the end of their operation. Twenty-one patients out of the remaining 294 patients developed sPOPE. Multivariate analysis identified resection containing segment 8 [relative risk (RR) 3.24, P = .022], intraoperative bleeding ≥ 500 g (RR 4.02, P = .008), intraoperative diaphragmatic incision (RR 6.96, P = .042) and open hepatectomy (RR 7.51, P = .016) as independently associated with sPOPE. The estimated probability of sPOPE ranged from 0.4% in patients with none of these factors to 73.4% in the presence of all factors. Among the 31 patients who received a preventive chest tube, more patients in the high-risk group defined by the model had postoperative pleural effusions compared to the low-risk group (P = .012).

CONCLUSION

Our predictive model for sPOPE using four risk factors allows for reliable prediction and may be useful for selection of preventive chest tube in patients undergoing hepatectomy.

Rupture of a huge infectious abdominal chronic expanding hematoma

A 72-year-old woman was referred to our hospital with the diagnosis of peritonitis due to the rupture of a huge abdominal cystic tumor, 27 cm in diameter. Abdominal computed tomography 14 years before revealed the tumor, which was 18 cm in diameter. She had undergone no examinations or treatment in the interim. She was in shock upon presentation to our hospital. She was intubated immediately and underwent an emergent laparotomy. The huge ruptured tumor with adherent small intestine was resected. The tumor weighed 6 kg and consisted of solid and cystic components filled with 4 kg of brown feces-like fluid. Bacteroides fragilis was detected in a fluid specimen. The cystic component of the tumor was filled with old blood clots, and a portion of the tumor wall was highly calcified. Old blood and fibrin with blood vessels of various sizes inside the tumor were observed during the pathologic evaluation; there were no malignant features. The final pathologic diagnosis was a chronic expanding hematoma (CEH). The patient had an uneventful recovery and was discharged 16 days post-operatively. She was involved in a traffic accident approximately 30 years before the current hospital admission; however, she did not recall if she had abdominal pain at that time. A CEH is a benign lesion, but rupture of a CEH can be life-threatening.

Efficacy of delayed primary closure with intrawound continuous negative pressure and irrigation treatment after surgery for colorectal perforation

AIM

Surgical-site infections (SSIs) often occur after surgery for colorectal perforation. We introduced delayed primary closure (DPC) after intrawound continuous negative pressure and irrigation treatment (IW-CONPIT) to prevent SSIs. We aimed to evaluate the efficacy of DPC after IW-CONPIT compared with primary closure (PC) after surgery for colorectal perforation.

METHODS

We undertook a retrospective study including 22 patients who underwent DPC (DPC group) and 18 patients who underwent PC (PC group) at our hospital between April 2015 and January 2017. The primary outcome was the SSI rate. The secondary outcomes were other complications (<30 days), length of hospital stay, and costs.

RESULTS

The SSI rate was significantly lower in the DPC group than in the PC group (40% vs. 94%, P = 0.0006). Moreover, superficial and deep incisional SSIs, infectious complications, and Clavien-Dindo classification grade ≥ 2 complications were also significantly diminished in the DPC group. Conversely, the length of hospital stay and costs were not significantly different between the two groups. Multivariate analyses revealed that the significant independent protective factor against SSI after surgery for colorectal perforation was DPC after IW-CONPIT (odds ratio 0.04; 95% confidence interval, 0.002-0.25).

CONCLUSION

Delayed primary closure after IW-CONPIT reduced SSIs after surgery for colorectal perforation compared with PC.

[Perforated Marginal Ulcer after Subtotal Stomach Preserving Pancreaticoduodenectomy-Report of Five Cases]

PURPOSE

Perforated marginal ulcer after pancreaticoduodenectomy(PD)is a delayed complication. We evaluated the characteristics of the patients presenting perforated marginal ulcer after PD.

METHODS

Five cases of perforated marginal ulcer after PD were reported at our hospital between 2008 and 2018, and the characteristics of these patients were evaluated.

RESULTS

All 5 patients(4 females)with median age 73 years underwent subtotal stomach-preserving PD(SSPPD). In spite of the administration of gastric antisecretory medication, perforated marginal ulcer occurred in 3 patients(60%). All patients were treated with direct suture and omentum patch, and no mortality was reported.

CONCLUSIONS

The perforating marginal ulcer after SSPPD occurred despite the administration of the gastric antisecretory medication. Treatment with direct suture and omentum patch was effective in perforated marginal ulcer after SSPPD.

[Primary Small Intestinal Cancer-A Clinicopathological Study of Seven Cases]

The clinicopathological features of primarysmall intestinal cancer were assessed retrospectively. Seven patients underwent resection of small bowel cancer in our hospital between June 2011 and January 2019. The mean age of the patients was 62.9 years, and the male to female ratio was 4:3. Five patients were symptomatic, and the correct preoperative diagnosis rate was 28.6%. The average tumor diameter was 5.3 cm, and the median resected intestine length was 25 cm. Histopathological examination revealed that there were 2 patients with poorlydifferentiated tumors and 3 patients with pStage ⅡA, 3 with pStage ⅡB, and 1 with pStage ⅢA disease. Recurrence after surgeryoccurred in 4 patients, including local recurrence in 2 patients and lymph node recurrence in 1 patient. Median survival was 24.5 months. The resected intestinal length was longer and the mesenteric arterydissection was more extensive in survivors than in dead patients. In contrast, the dead patients were older than the survivors and had undifferentiated tumor, ly2/ly3, lymph node metastasis, and recurrence. Moreover, recur- rence occurred in 4 patients who had lymph node metastasis, and/or undifferentiated tumor type, and/or ly2/ly3. An adequate intestinal excision margin along with mesenteric lymph node dissection might be required to improve the survival of patients with primaryintestinal cancer.

Case report of aggressive treatments for large-cell neuroendocrine carcinoma of the esophagus

•

Neuroendocrine carcinoma of the esophagus is a rare and highly aggressive disease.

•

A case of large-cell neuroendocrine carcinoma of the esophagus in a 73-year-old male patient with aggressive surgical treatment.

•

We performed subtotal esophagectomy, partial hepatectomy, radiotherapy and chemotherapy using cisplatin and irinotecan.

•

We believe that aggressive treatment can become one treatment option with the aim of extending survival.

Introduction

Neuroendocrine carcinoma of the esophagus is a rare and highly aggressive disease, and the biological features are poorly understood.

Presentation of case

We report a case of large-cell neuroendocrine carcinoma of the esophagus in a 73-year-old male patient with aggressive surgical treatment. Upper gastrointestinal endoscopy revealed an esophageal large mass. Histological examination of biopsy specimens indicated a neuroendocrine carcinoma. First, we performed subtotal esophagectomy with lymphadenectomy, but he experienced metastasis at the liver and rib 5 months later. Next, we performed partial hepatectomy and radiotherapy for rib metastasis, but he experienced metastasis at the left pulmonary hilar lymph node and sacral bone. Finally, we performed chemotherapy using cisplatin and irinotecan.

Discussion

The therapeutic strategy for large-cell NEC of the esophagus is unestablished. Thus, accumulating the therapeutic results garnered from various treatment tools is considerably important.

Conclusion

Aggressive multimodal treatments including surgery have a possibility to gain better survival in patients with large-cell NEC of the esophagus.

Establishment of the complete life cycle of Spirometra (Cestoda: Diphyllobothriidae) in the laboratory using a newly isolated triploid clone

Methods to maintain the life cycle of pathogenic organisms become powerful tools for studying molecular and cellular bases of infectious diseases. Spirometra erinaceieuropaei is a parasitic tapeworm that causes sparganosis in humans. Because S. erinaceieuropaei has a complex life cycle with different stages and host species requirements, there have been no reports to establish the complete life cycle in the laboratory. In this study, using Cyclops as the first intermediate host, mouse as the experimental second intermediate host, and dog as the final host, we succeeded in maintaining S. erinaceieuropaei in the laboratory. By repeating the established life cycle five times, we obtained a clonal population of S. erinaceieuropaei from a single adult worm. A karyotype study showed that the chromosome of this clone is triploid (3n=27), indicating that a genetically uniform strain is established by apomictic reproduction. The strain was named Kawasaki triploid (Kt). A partial sequence of mitochondrial cytochrome c oxidase subunit 1 gene of the strain Kt showed more than 98% similarity with those of S. erinaceieuropaei isolates from Australia, China, and South Korea, and the resultant phylogeny indicated that the strain Kt is a member of a distinctive clade from East Asia and Oceania. Our system will be particularly useful for studies of S. erinaceieuropaei infection and human sparganosis.

[Clinical efficacy of octreotide acetate in cancer patients with malignant bowel symptoms depend on terminal stage]

There are many reports that octreotide acetate(SMS)is effective for terminally ill cancer patients with malignant bowel obstructions such as nausea, vomiting and abdominal distension. We retrospectively found that the clinical efficacy of SMS in 23 patients with these symptoms depended on the early terminal stage(about six months until death)or middle terminal stage(within one month until death). SMS was more effective to relieve abdominal distension(p=0. 01)and these bowel symptoms occurred among cancer patients in the early terminal stage rather than in the middle terminal stage(p<0. 001).

Multiple early gastric cancer with duodenal invasion

Background

Early gastric cancers with duodenal invasion are rare, and no previous case of multiple early gastric cancer, one invading the duodenal bulb, has been reported.

Case presentation

A 79-year-old woman was investigated for upper abdominal discomfort. Endoscopic examination revealed an irregular nodulated lesion in the antrum area, and a reddish aggregated-type semi-circumferential nodulated lesion extending from the prepyloric area to the duodenal bulb through the normal mucosa with the antrum lesion. Biopsy revealed a tubular adenoma for the antrum lesion and a well-differentiated tubular adenocarcinoma for the prepyloric lesion. Distal gastrectomy with sufficient duodenal resection was performed. Microscopically, the antrum lesion appeared as a papillary adenocarcinoma, and the prepyloric lesion as a mainly papillary adenocarcinoma which partially invaded the submucosa without any sequential elongation for endoscopic findings. The lesion extended into the duodenal bulb, and was 12 mm in length from the oral end of Brunner's gland's area and limited within the duodenal mucosa.

Conclusion

Here, we present an unusual case of multiple early gastric cancer, one of which invaded the duodenum with relative wide mucosal spreading. This case illustrates that even early stage cancers located in the gastric antrum, particularly in the prepyloric area can invade the duodenum directly.

Growth and development of Massaliatrema misgurni (Trematoda: Heterophyidae) in mice and its metacercarial morphology

The morphology of metacercariae of Massaliatrema misgurni Ohyama et al. (Ohyama et al., Parasitol Int 2001; 50; 267-71) was described, and their infectivity, egg output, growth and development in mice until day 35 post infection (PI) were studied. Metacercarial cysts from loaches imported from China to Japan were 199-349 microm in diameter and consisted of a very thick translucent outer layer and a refractile inner layer. Excysted metacercariae basically had the shape of miniature adults, and a pair of pre-developed testes but no other genital organs were recognized. The worm recovery rate from mice was 36.7-51.7% during days 3-7 PI, and decreased remarkably to 2.5 and 1.7% at days 28 and 35 PI. The prepatent period was 3-4 days, and the egg output quickly increased and sustained high levels at days 5-7 PI, then decreased suddenly at day 8 PI, and continued at a low level until day 28 PI. The size of the body and inner organs such as the oral sucker, pharynx, acetabulum, testes, ovary and seminal receptacle quickly increased until day 3 PI, and sustained at a plateau level until day 21 PI except testes which gradually decreased until 21 PI. The number of the uterine eggs increased with a short time lag compared to other genital organs and sustained a plateau level until day 21 PI. Compared with other Heterophyidae species, M. misgurni was characterized by the remarkably fast growth and development.

Characterization of the preferred stereochemistry for the neuropharmacologic actions of antillatoxin

Antillatoxin is a potent ichthyotoxin and cytotoxin previously discovered from the marine cyanobacterium Lyngbya majuscula. Ensuing studies of its mechanism of action showed it to activate the mammalian voltage-gated sodium channel at a pharmacological site that is distinct from any previously described. The structure of antillatoxin, initially formulated from spectroscopic information, was subsequently corrected at one stereocenter (C-4) as a result of synthesis of four different antillatoxin stereoisomers (all possible C-4 and C-5 diastereomers). In the current study these four stereoisomers, (4R,5R)-, (4S,5R)-, (4S,5S)-, and (4R,5S)-antillatoxin, were characterized in five different biological assay systems: ichthyotoxicity to goldfish, microphysiometry using cerebellar granule cells (CGCs), lactose dehydrogenase efflux from CGCs, monitoring of intracellular Ca(2+) concentrations in CGCs, and cytotoxicity to Neuro 2a cells. Across these various biological measures there was great consistency in that the natural antillatoxin (the 4R,5R-isomer) was greater than 25-fold more potent than any of the other stereoisomers. Detailed NMR studies provided a number of torsion and distance constraints that were modeled using the MM2 force field to yield predicted solution structures of the four antillatoxin stereoisomers. The macrocycle and side chain of natural (4R,5R)-antillatoxin present an overall "L-shaped" topology with an accumulation of polar substituents on the external surface of the macrocycle and a hydrogen bond between N(H)-7' and the C(O)-1 carbonyl. The decreased potency of the three non-naturally occurring antillatoxin stereoisomers is certainly a result of their dramatically altered overall molecular topologies.

Use of nitrogen stable isotope ratio of periphyton for monitoring nitrogen sources in a river system

In order to confirm the usefulness of the N stable isotope ratio of periphyton (mainly composed of attached algae) as an indicator for monitoring the N sources in river watersheds, we measured the isotope ratio of periphyton along the Chikuma River. In the river, both the concentrations of dissolved total nitrogen (DTN) and the delta15N values of periphyton increased downstream. Specific nitrogen loading rates (SNLR) calculated from administrative data also showed an increase downstream from 7 to 11 kg N ha(-1) yr(-1), with the increasing contribution by sewage and livestock waste from 6 to 40% to total N loading. There are significant positive relationships between the DTN concentration and the SNLR (r2=0.54, P<0.05), and the delta15N values of periphyton and the SNLR (r2=0.78, P<0.05). The increase in DTN concentration reflected the increase in input of N loading. The increase in delta15N of periphyton might reflect the increase in relative contribution by sewage and livestock waste down the river, especially the increase in sewage. The present study indicates the usefulness of the N stable isotope ratio of periphyton as an indicator for monitoring N sources in a river system.

Massaliatrema misgurni n. sp. (Trematoda: Heterophyidae) whose metacercariae encyst in loaches (Misgurnus anguillicaudatus)

Hitherto unknown metacercariae were found encysted in loaches (Misgurnus anguillicaudatus) from China. They were experimentally fed to golden hamsters, and gravid adults were recovered 1 week post-infection from their small intestines. A new species, Massaliatrema misgurni n. sp. (Heterophyidae), is described from the adults. This new species is different from M. gyrinicola Dollfus and Timon-David, 1960, in having a smaller acetabulum/oral sucker ratio, less branched vitellaria widely entering the intercecal anteroacetabular area and an almost median seminal receptacle; and from M. yamashitai Kamiya and Ohbayashi, 1975, in having a larger acetabulum/oral sucker ratio, with the seminal vesicle situated in the uterine loop and the vitellaria entering the intercecal anteroacetabular area. This report is the first record of M. anguillicaudatus as a second intermediate host of the genus Massaliatrema Dollfus and Timon-David, 1960.

Chiral phosphine-free Pd-mediated asymmetric allylation of prochiral enolate with a chiral phase-transfer catalyst

[reaction: see text]. A chiral phase-transfer catalyst has been applied to the asymmetric allylation of the tert-butyl glycinate-benzophenone Schiff base with various allylic acetates for the first time to give the allylated products in good yields and with comparable to higher enantioselectivity than for asymmetric alkylation at the same temperature (91-96% ee) without any chiral ligands for coordinating to the palladium.

Antillatoxin B, a neurotoxic lipopeptide from the marine cyanobacterium Lyngbya majuscula

Bioassay-guided fractionation of organic extracts from two Lyngbya majuscula collections led to the isolation of a new secondary metabolite, antillatoxin B, an unusual N-methyl homophenylalanine analogue of the potent neurotoxin antillatoxin. Its structure was deduced from 2D NMR and data comparisons with antillatoxin. Antillatoxin B exhibited significant sodium channel-activating (EC(50) = 1.77 microM) and ichthyotoxic (LC(50) = 1 microM) properties.

Antillatoxin is a marine cyanobacterial toxin that potently activates voltage-gated sodium channels

Antillatoxin (ATX) is a lipopeptide derived from the pantropical marine cyanobacterium Lyngbya majuscula. ATX is neurotoxic in primary cultures of rat cerebellar granule cells, and this neuronal death is prevented by either N-methyl-d-aspartate (NMDA) receptor antagonists or tetrodotoxin. To further explore the potential interaction of ATX with voltage-gated sodium channels, we assessed the influence of tetrodotoxin on ATX-induced Ca2+ influx in cerebellar granule cells. The rapid increase in intracellular Ca2+ produced by ATX (100 nM) was antagonized in a concentration-dependent manner by tetrodotoxin. Additional, more direct, evidence for an interaction with voltage-gated sodium channels was derived from the ATX-induced allosteric enhancement of [3H]batrachotoxin binding to neurotoxin site 2 of the alpha subunit of the sodium channel. ATX, moreover, produced a strong synergistic stimulation of [3H]batrachotoxin binding in combination with brevetoxin, which is a ligand for neurotoxin site 5 on the voltage-gated sodium channel. Positive allosteric interactions were not observed between ATX and either alpha-scorpion toxin or the pyrethroid deltamethrin. That ATX interaction with voltage-gated sodium channels produces a gain of function was demonstrated by the concentration-dependent and tetrodotoxin-sensitive stimulation of 22Na+ influx in cerebellar granule cells exposed to ATX. Together these results demonstrate that the lipopeptide ATX is an activator of voltage-gated sodium channels. The neurotoxic actions of ATX therefore resemble those of brevetoxins that produce neural insult through depolarization-evoked Na+ load, glutamate release, relief of Mg2+ block of NMDA receptors, and Ca2+ influx.

Sequential histopathological changes in vivo after suicide gene therapy of gastric cancer induced by N-methyl-N'-nitro-N-nitrosoguanidine in rats

Gastrointestinal cancer is the most important clinical target of gene therapy. Suicide gene therapy, such as with the herpes simplex virus type 1 thymidine kinase (HSV-TK) gene, has been shown to exert antitumor efficacy in various cancer models in vitro. We previously reported in situ gene transfer and gene therapy for gastric cancer induced by N-ethyl-N'-nitro-N-nitrosoguanidine (ENNG) in dogs. Here, we describe the sequential histopathological changes after suicide gene therapy of N-methyl-N'-nitro-N-nitrosoguanidine (MNNG)-induced gastric cancer in rats. Gastric tumors were induced by MNNG in 38 / 73 (52%) of Wistar strain rats. The suicide gene therapy group (14 rats) was subjected to in situ gene transfer with a recombinant adenovirus vector carrying the HSV-TK gene driven by CAG promoter (Ad.CAGHSV-TK) in gastric tumor, followed by the antiviral drug ganciclovir (GCV). To observe the histopathological changes at various times after HSV-TK / GCV gene therapy, groups of animals were sacrificed at 3, 8, and 30 days after gene transfer. Apoptosis in the gastric tumors was detected by the TUNEL method to assess the efficacy of HSV-TK / GCV gene therapy, and it was marked in the 8- and 30-day treatment groups compared to the sham operation controls (P < 0.001). Various histopathological changes, degeneration of cancer tissue and fibrosis after necrosis and apoptosis were significantly greater in the 30-day treatment group. The HSV-TK gene was detectable in peripheral blood by PCR until 30 days after gene transfer. These results may be useful in devising a method of suicide gene therapy for humans.

Asymmetric alkylation of tert-butyl glycinate Schiff base with chiral quaternary ammonium salt under micellar conditions

[reaction: see text] The asymmetric alkylation of the tert-butyl glycinate-benzophenone Schiff base 1 with various arylmethyl bromides catalyzed by O-allyl-N-(9-anthracenylmethyl)cinchonidinium bromide (2) proceeded smoothly under micellar conditions (5 equiv of 1 M KOH and 0.4 equiv of Triton X-100) to give the alkylated products in good yields and with good enantioselectivity (72-85% ee), depending on the electrophiles.

Immunohistochemical analysis of distribution of RON receptor tyrosine kinase in human digestive organs

The immunohistochemical distribution of RON receptor tyrosine kinase in digestive organs of both human fetus and adult, including the esophagus, stomach, duodenum, small intestine, colon, rectum, liver, gallbladder, pancreas, and spleen, was investigated semiquantitively using an affinity-purified rabbit polyclonal antibody. RON was observed to be widely distributed throughout various digestive organs and cell types in humans. The immunoreactivity for RON was observed in the epithelium of the esophagus, small intestine, colon, hepatocytes, Kupffer cells, and splenic macrophages both in the adult and the fetus, suggesting that the MSP/RON signaling pathway possesses the proper biological properties to possibly be involved in morphogenesis or differentiation of cells in these organs and cell types. Several organs differed in immunoreactivity between adult and fetus. No immunoreactive cells were found in the pancreas of adults; however, immunoreactivity was observed in acinar cells and in some of the duct or ductular cells and endocrine cells of the islet of the fetus. Similarly, immunoreactivity was not observed in gastric mucosa except in the intestinal metaplastic cells in adults; however, immunoreactivity was found in the foveolar epithelium of the stomach of the fetus. Although the biological significance of RON in malignancy is unclear, the presence of RON immunoreactivity in the fetus and it lack in the adult may indicate that RON is a oncofetal substance in human pancreas and stomach.

[Gastric cancer--novel strategy of gene therapy for gastric cancer]

Recently stage-oriented treatment for gastric cancer has been done in Japan. Endoscopic mucosal resection for intramucosal cancer and wedge resection under laparoscopy for minimal invasive cancer in the stomach have been performed. For advanced gastric cancer, extended lymph node dissection(D2) has been applied as standard treatment in Japan. However, new strategy has been required for advanced gastric cancer with distant lymph node metastasis and/or peritoneal dissemination. It is well known that gene therapy for cancer has limitation of efficacy, but we believe the new strategy will be available in post-genome era for gastric cancer treatment using 1. developing novel adenovirus, 2. usage of drug delivery system and 3. effective treatment for adverse effect.

Hermitamides A and B, toxic malyngamide-type natural products from the marine cyanobacterium Lyngbya majuscula

A Papua New Guinea collection of the marine cyanobacterium Lyngbya majuscula yielded two new and toxic natural products, hermitamides A (1) and B (2). The hermitamides were isolated using a brine shrimp (Artemia salina) toxicity assay. Planar chemical structures of 1 and 2 were established through 1D and 2D NMR, as well as FABMS data. Semisyntheses of hermitamides A (1) and B (2) were achieved by coupling the acid chloride derivative of 7(S)-methoxytetradec-4(E)-enoic acid (4), obtained from the same cyanobacterium collection, and the respective free amines, phenethylamine and tryptamine. Hermitamides A (1) and B (2) exhibited LD(50) values of 5 microM and 18 microM in the brine shrimp bioassay, and an IC(50) values of 2.2 microM and 5.5 microM to Neuro-2a neuroblastoma cells in tissue culture, respectively. Hermitamide A was mildly ichthyotoxic to goldfish, with an LD(50) value of 19 microM, while hermitamide B was inactive at 25 microM.

Epithelioid trophoblastic tumor: morphological and immunohistochemical study of three lung lesions

Epithelioid trophoblastic tumor (ETT) is a term proposed for an unusual variant of trophoblastic tumor that is closely related to choriocarcinoma but shows monomorphic growth of highly atypical trophoblastic cells instead of the typical dimorphic pattern of choriocarcinoma. We report here 3 cases of ETT, all of which were lung lesions probably originating from uterine trophoblastic disease. The antecedent pregnancies of the 3 cases were hydatidiform mole, invasive mole, and term pregnancy, respectively. The tumors were composed of highly atypical mononucleate cells, which mainly involved alveolar spaces, forming nests with central eosinophilic necrosis. Multinucleate giant cells were found within the nests, but they were fewer in number than in typical choriocarcinoma. The tumors were not associated with extensive hemorrhage or necrosis, except for 1 case, in which the ETT was combined with typical dimorphic choriocarcinoma. Immunohistochemically, multinucleate giant cells and occasional mononucleate tumor cells showed positivity for human chorionic gonadotropin. Staining for human placental lactogen was positive in rare multinucleate giant cells, and in 1 case, tumor cells showed diffuse positivity for placental alkaline phosphatase. Because ETT has a remarkably epithelioid appearance in cytological and architectural features, differentiation from the epithelial malignancies is problematic. Trophoblastic markers are frequently expressed in nontrophoblastic tumors, and reactivity for those markers alone is not sufficient for exclusion of other tumors. Rather, evidence of ETT comes from a combination of morphological features, immunohistochemical study, and clinical history.

Presence of RON receptor tyrosine kinase and its splicing variant in malignant and non-malignant human colonic mucosa

The presence of RON and its variant isoform in malignant and non-malignant human colonic tissues was examined by immunohistochemistry using paraffin-embedded sections and RT-PCR analysis followed by direct sequencing of PCR product using RNAs isolated from frozen tissues. In normal colonic mucosa, RON was uniformly expressed in crypt cells, especially in the bottom of crypta. On the other hand, the expression was distributed heterogeneously in adenomas and in colon cancer. The expression of RON was significantly related to the degree of differentiation of colon cancer and the deletion of the expression was observed in colon cancer specimens with high incidence. The RT-PCR analysis of RNA isolated from non-malignant and malignant colonic tissue revealed the presence of two RON mRNA isoforms with 432-bp and 286-bp. Direct sequencing of major product of 432-bp was revealed to be identical to that of human wild-type RON. On the other hand, major product of 286-bp was revealed to be almost identical to that of a splicing variant of RON transcript which has been found in human gastric cancer cell line, KATO-III. The results obtained in this study may indicate that both wild-type RON and its variant isoform play an important role in regulating the normal function of colonic mucosa such as differentiation and motile activity and the expression of both wild-type RON and its variant isoform could be considered to be reduced during malignancy of human colonic mucosa.

In situ gene transfer and suicide gene therapy of gastric cancer induced by N-ethyl-N'-nitro-N-nitrosoguanidine in dogs

Gene therapy could potentially revolutionize the treatment of gastrointestinal (GI) tract cancer. The aim of this study was to establish a practical method of gene transfer which would be applicable to human gastric cancer. Retrovirus or/and adenovirus vectors carrying the lacZ marker gene were transferred in situ by needle through an endoscopic biopsy channel into primary gastric cancer in six male beagle dogs that had been treated with N-ethyl-N'-nitro-N-nitrosoguanidine (ENNG). In addition, an adenovirus vector carrying the herpes simplex virus thymidine kinase (Ad.CAGHSV-TK) gene was introduced in situ into cancer tissues in the stomach of three dogs, and the animals were treated with intravenous ganciclovir (GCV). Retrovirus-producing cells which expressed the lacZ gene were specifically localized to the injection site in the stomach. The lacZ gene was more widely transferred into the tumor by the adenovirus vector than by retrovirus-producing cells. Improvement of the needle used for gene transfer and the use of multiple injections per tumor led to more diffuse transfer of the vector into the tumor. The Ad.CAGlacZ gene was also transferred into regional lymph nodes of the stomach. Moderate to diffuse degeneration of the primary cancer tissues of the stomach was found after Ad.CAGHSV-TK/GCV gene therapy. Moreover, almost complete tissue degeneration was observed in the regional lymph nodes of the stomach. An adverse effect of HSV-TK/GCV gene therapy was acute hepatotoxicity, which was not found after Ad.CAGlacZ gene transfer, but was found after high-titer Ad.CAGHSV-TK gene transfer followed by GCV. These findings suggest that in situ gene transfer of a suicide gene followed by prodrug treatment may be applicable not only to primary tumors, but also to lymph node metastases of gastric cancer, though further study of both beneficial and adverse effects is required before clinical usage.

Induction of human leukocyte antigen (HLA)-A2-restricted and MAGE-3-gene-derived peptide-specific cytolytic T lymphocytes using cultured dendritic cells from an HLA-A2 esophageal cancer patient

BACKGROUND AND OBJECTIVES

Using peripheral blood mononuclear cells (PBMCs) from a 10-year survivor with established human leukocyte antigen (HLA)-A2(+) and MAGE-3(+) esophageal cancer cell line (KYSE-170), we examined the induction of HLA-A2-restricted and MAGE-3-gene-derived peptide (FLWGPRALV, amino acids 271-279)-specific cytolytic T lymphocytes (CTLs).

METHODS

Autologous dendritic cells (DCs) cultured with granulocyte-macrophage colony stimulating factor and interleukin-4 were used as antigen presenting cells. PBMCs were stimulated by peptide-pulsed DCs in vitro.

RESULTS

PBMC cocultured with FLWGPRALV-pulsed DCs could induce the relevant peptide-specific CTLs, which had tumor necrosis factor production and specific cytotoxicity against relevant peptide-pulsed autologous DCs (34%, effector:target ratio = 40:1). Moreover, they showed specific cytotoxicity against the autologous esophageal cancer cell line KYSE-170 (17%, effector:target ratio = 40:1).

CONCLUSIONS

These results suggest that FLWGPRALV-pulsed cultured DCs would be a potent candidate for peptide vaccine against HLA-A2(+) and MAGE-3(+) esophageal cancer.

Reduction of tumorigenicity by an interferon-gamma-gene-transduced tumor on another syngeneic tumor in a murine model

To evaluate the effect of interferon-gamma-gene-transduced cells, DS mice were inoculated into their footpads with syngeneic mammary adenocarcinoma SC42 admixed with interferon-gamma producing mammary adenocarcinoma SC115Kgamma, which had been established by an interferon-gamma-gene transduction in another syngeneic mammary adenocarcinoma SC115 using retroviral vectors. These mice rejected both tumor cells and developed resistance to subsequent challenges with either SC115 or SC42 cells inoculated into their opposite posterior footpads. These results thus indicate that systemic immunological memory to each of the independent tumor cell lines developed in these mice. Although the SC42 cells admixed with irradiated SC115Kgamma cells were rejected by these mice, the SC42 cells admixed with irradiated SC115neoR, in which the neo-gene had been transduced, were observed to proliferate. Tumor rejection was reversed by an in vivo administration of anti-interferon-gamma antibody, thus suggesting that locally produced interferon-gamma plays an important role in tumor elimination and immunological memory induction. In conclusion, interferon-gamma-gene-transduced tumor cells are therefore considered to have a therapeutic potential for other types of malignant tumor cell lines.

Prognostic values of MUC-1 molecule expressing cytokine receptor-like epitope and DF3 in patients with gastric carcinoma

As recently reported, DF3/MUC-1 molecules having cytokine receptor-like sequences (CRL) at the extracellular region, are likely to function in signal transduction pathways. To elucidate the functional significance of CRL expressed on the DF3/MUC1 molecule, immunohistochemical localization of CRL and/or DF3 was investigated in cases of 115 patients with gastric carcinomas, treated by surgical resection. CRL was detected in 65 of 115 patients (56.5%), DF3 in 85 (73.9%), and both DF3 and CRL in 52 (45.2%). The combined immunohistochemical analysis of CRL and/or DF3, revealed that simultaneous expression of DF3 and CRL (DF3+/CRL+) significantly correlated to lymph node metastasis and to blood vessel invasion, and that patients with DF3+/CRL+-tumors survived for a significantly shorter period after surgery than did the other three groups (DF3+/CRL-, DF3-/CRL+, and DF3-/CRL-). Multivariate analysis showed independent prognostic significance for DF3+/CRL+ expression (hazard ratio [HR]=2.733, P=0.0085), and surgical cure (HR=4.334, P=0.003). To investigate the biological role of the simultaneous expression of DF3 and CRL, we constructed DF3-/CRL+ (NR-MC-38) and DF3+/CRL+ (R-MC-38) cells by transducing a mouse colon adenocarcinoma cell line MC-38 expressing neither DF3 nor CRL with MUC-1 cDNA containing ten tandem repeats (R-MC-38) or MUC-1 cDNA devoid of tandem repeats (NR-MC-38). R-MC-38 (DF3+/CRL+) cells were more invasive than NR-MC-38 (DF3-/CRL+) and MC-38 (DF3-/CRL-) cells. When these transfectants were incubated with pAb CRL, the invasiveness of R-MC-38 (DF3+/CRL+) was strikingly elevated over the case with native MC-38 (DF3-/CRL-) and NR-MC-38 (DF3-/CRL+) cells. The pAb CRL-induced invasiveness of R-MC-38 cells was inhibited by adding mAb DF3 or CRL peptides together with pAb CRL. These results suggest that an expression of DF3/MUC1 is highly associated with cell-invasiveness, and the DF3/MUC1-associated invasiveness is amplified by CRL. Thus DF3+/CRL+-MUC-1 molecule seems to be closely involved in a poor prognosis for gastric cancer patients.

Analysis of effector cells in tumor-bearing mice pre-treated with active specific immunization followed by cyclophosphamide

In order to analyse the effector population in an immunization model, we treated BALB/c mice with intraperitoneal (i.p.) active specific immunization (ASI), which consists of interleukin (IL)-1-beta and sonicated tumor supernatant (SS) of a plasmacytoma MOPC-104E followed by i.p. injection of cyclophosphamide (CY). This ASI-CY treatment provoked a protective immunity against i.p. tumor inoculation more strongly than that of ASI alone. The main effector cells in tumor neutralizing assay were CD4+ T cells at this pont. The number of spleen cells of the ASI-CY treated mice were significantly lower than that of ASI alone treated mice but it increased significantly 6 days thereafter while this increase was not observed on the mice treated with ASI alone. The spleen cells of the ASI-CY treated mice responded to SS in vitro in the presence of IL-2, more profoundly in CD4 enriched population which produced high amount of TNF-alpha. In vivo tumor-neutralizing activity at a later stage was dependent on CD8+ T cells in addition to CD4+ T cells. These results suggest that antitumor activity by ASI and CY is transduced by sequential population shift from CD4 alone to both of CD4 and CD8.

Effects of thyrotropin-releasing hormone and its metabolites, Cyclo(His-Pro) and TRH-OH, on growth hormone and prolactin synthesis in primary cultured pituitary cells of the common carp, Cyprinus carpio

The effects of thyrotropin-releasing hormone (TRH) and its metabolites, cyclo(His-Pro) and TRH-OH, on growth hormone (GH) and prolactin (PRL) synthesis were investigated using primary cultured pituitary cells of the common carp, Cyprinus carpio. The effects of these pep tides on GH and PRL were compared to those of human GH-releasing hormone (hGHRH) and somatostatin (somatotropin-releasing inhibiting factor; SRIF). GH and PRL synthesis were determined by measuring the incorporation of [3H]leucine into GH and PRL. TRH stimulated the release of newly synthesized GH and PRL, but not thyroid-stimulating hormone. In addition, TRH stimulated a dose-related increase in the release of newly synthesized GH and PRL at 10(-9) to 10(-7) M. Cyclo(His-Pro) stimulated the release of newly synthesized GH dose- dependently. TRH, cyclo(His-Pro), and hGHRH stimulated GH synthesis, while SRIF inhibited this at 10(-7) M. The release of newly synthesized PRL into culture medium was also stimulated by TRH and hGHRH, but inhibited by SRIF. PRL synthesis was not affected by TRH-OH and cyclo(His-Pro). Intracellular contents of GH and PRL in the pituitary did not change significantly. The present study demonstrates that TRH plays an important role in both GH and PRL synthesis and release. This is the first report in which the effects of cyclo(His-Pro) on GH synthesis in teleosts are demonstrated.

Cyclophosphamide given after active specific immunization augments antitumor immunity by modulation of Th1 commitment of CD4+ T cells

BACKGROUND AND OBJECTIVES

In order to evaluate the regulatory effect of cyclophosphamide (CPA) on active specific immunization (ASI)-induced antitumor immunity, we examined the timing of CPA (100 mg/kg) with ASI, and focused on whether CPA given after ASI augments antitumor immunity by modulation of Th1 commitment of CD4+ T cells.

METHODS

We examined the effect of CPA combined with ASI using sonicated tumor supernatant (SS) and recombinant interleukin-1 beta (rIL-1 beta).

RESULTS

Survival of i.p. tumor inoculated mice after ASI (days -12, -9, and -6) followed by 100 mg/kg CPA (day -3) (ASI-CPA) was significantly prolonged compared with that of mice treated with ASI alone, whereas CPA (day -15) treatment before ASI (CPA-ASI) completely abrogated the survival prolongation by ASI alone. In early stage (day 0) after ASI-CPA treatment, the CD4+ T cells were determined to play an important role in the protective immunity for the following reasons: 1) the CD4+/CD8+ ratio of spleen cells from immunized mice was higher than that of the control or CPA alone treated group; and 2) the tumor neutralizing activity of fresh spleen cells was abrogated by CD4+ T-cell depletion in vitro. CD4+ T cells of mice treated with ASI-CPA produced more interferon (IFN)-gamma and IL-2 and less IL-4 than those of the ASI alone group.

CONCLUSIONS

These results suggest that the protective immunity induced by ASI was augmented through the modification of the Th1 and Th2 balance by CPA injection after ASI.

Preferential localization of human CD5+ B cells in the peritoneal cavity

In a transgenic mouse model of autoimmune haemolytic anaemia, CD5+ B lymphocytes localized in the peritoneal cavity are shown to play an important role in the onset of autoimmune disease. The authors have examined whether CD5+ B cells are present in the peritoneal cavity of 12 human individuals with non-invasive gastrointestinal tumours and found that in humans CD5+ B cells preferentially lodge in the peritoneal cavity as compared to the peripheral blood and spleen while the numbers of the peritoneal B lymphocytes in humans are much lower than in mice and vary widely between individuals.

The effectiveness of active specific immunotherapy using interferon-gamma-gene-transduced tumor cells in a murine tumor model

Active specific immunotherapy was examined in BALB/c mice using sonicated tumor extract(SE) from plasmacytoma MOPC104E or interferon-gamma-(IFN-gamma)-gene-transduced MOPC104E (Mu gamma), employing interleukin-1 (IL-1) as an adjuvant. Subcutaneous (s.c.) MOPC104E tumor growth was significantly suppressed in mice given a single preimmunization of IL-1 plus Mu gamma-SE, 9 days prior to inoculation, whereas the tumor growth in mice similarly pretreated with IL-1 alone or IL-1 plus MOPC104E-SE(MOPC-SE) was not affected; the mean tumor diameters on day 21 being 6.8 mm, 15.3 mm, and 13.2 mm, respectively. Two-dose preimmunization with Mu gamma-SE alone or IL-1 alone given 10 and 7 days prior to s.c. inoculation also resulted in profound suppression of tumor growth compared to the control. As postsurgical immunization, MOPC104E cells were injected into the foot pads of mice, followed by amputation of the tumor-bearing foot 20 days later, then treatment with IL-1 plus MOPC-SE or IL-1 plus Mu gamma-SE on days 4, 7, and 10 after the amputation. The mean survival of the mice treated with IL-1 plus Mu gamma-SE was significantly prolonged compared to that of the mice treated with IL-1 plus MOPC-SE, at 90.3 days vs 40.9 days, respectively (P < 0.05 by the Cox-Mantel test). These results suggest that SE prepared from IFN-gamma-gene-transduced MOPC104E is more effective for active specific immunotherapy than SE prepared from MOPC104E.

Detection of colorectal carcinoma cells in circulating peripheral blood by reverse transcription-polymerase chain reaction targeting cytokeratin-20 mRNA

For the detection of circulating colorectal carcinoma cells, we investigated the presence of cytokeratin 20 (CK 20) mRNA in the peripheral blood of colorectal carcinoma patients. Application of our published technique resulted in analysis by reverse transcription followed by three-step nested polymerase chain reaction. This analysis could detect a single Colo 205 colon cancer cell mixed with 1 ml of blood. Our system also successfully detected the presence of CK 20 mRNA in actual patients' peripheral blood samples. Our highly sensitive and specific system for the detection of CK-20 mRNA from patients' peripheral blood thus seems to be useful for screening for circulating colorectal carcinoma cells.

Identification and estimation of microcystins in freshwater mussels

Accumulation of microcystins mainly produced by cyanobacteria Microcystis was investigated for freshwater mussels and fishes collected from a lake where heavy blooms of Microcystis occurred every year. The identification of microcystins was performed by HPLC equipped with a frit FAB mass spectrometer. Microcystins LR and RR were identified in the mussels Unio douglasiae and Anadonta woodiana, whereas no microcystin was identified by the present method in fishes, such as Cyprinus carpio, Carassius carassius, and Hypomesius transpacificus.

Immunohistochemical expression of SKALP/elafin in squamous cell carcinoma of the oesophagus

In this study, the immunohistochemical expression of a new inducible elastase inhibitor, SKALP (skin-derived anti-leucoproteinase)/elafin, in the tissue of squamous cell carcinoma and uninvolved oesophageal mucosa was studied using a polyclonal rabbit anti-serum against SKALP/elafin. The results were compared with the immunohistochemical staining of proliferating cell nuclear antigen (PCNA) and the TUNEL assay in serial sections. In non-malignant oesophageal mucosa, the expression of SKALP/elafin was localized in the cells of the stratified zone overlying the PCNA-positive basal zone. In oesophageal cancer, the incidence of the expression was significantly related to the degree of the differentiation of the tumour. Characteristically, the expression was almost limited in tumour cell nests that had a clear squamous phenotype. In tumour cell nests, the expression of SKALP/elafin was localized in the cells overlying PCNA-expressing cells and no expression was found in the cells that expressed PCNA; DNA fragmentation was often observed in the same cell layers as those in which SKALP/elafin immunoreactivity was found. This enzyme inhibitor is speculated to be involved in the induction of the cell differentiation and apoptosis of human squamous cell carcinoma cells of the oesophagus.

Identification of carcinoembryonic antigen mRNA in circulating peripheral blood of pancreatic carcinoma and gastric carcinoma patients

To detect adenocarcinoma cells in the circulating peripheral blood, we "analyzed the presence of carcinoembryonic antigen (CEA) mRNA in the peripheral blood obtained from patients with pancreatic carcinoma (PC) or with gastric carcinoma (GC) and also, as controls, from pancreatitis or gastritis patients without carcinomas, a gastric lymphoma patient and four healthy volunteers. Because of the small number of carcinoma cells expected in the peripheral blood, the analysis was performed by the reverse transcription followed by an original two-step polymerase chain reaction. By this sensitive method, 3 of 9 PC patients and 2 of 9 GC patients were positive for CEA mRNA. Except for 1 highly advanced PC patient, 3 of 4 CEA mRNA-positive patients developed recurrence after curative resection or liver metastasis after palliative operation within 9 months after the analysis. None of the control patients was positive for CEA mRNA in the peripheral blood. The results suggest that our sensitive RT-PCR method for detecting CEA mRNA in the peripheral blood is practically useful to find the hematogenous spreading of adenocarcinoma cells.

Malignant fibrous histiocytoma of the pancreas

An extremely rare case of malignant fibrous histiocytoma in the pancreas is reported. A 70-year-old man complained of upper abdominal discomfort. A tumor in the head of the pancreas was demonstrated by ultrasonography and computed tomography. The surgical specimen revealed a relatively well demarcated tumor, 9 x 7 x 6.5 cm in size. Microscopically, fibroblastic, histiocytic, and multinucleated giant tumor cells were observed in the myxoid area, but some tumor cells had proliferated in a storiform-pleomorphic pattern. Immunohistochemically, some tumor cells were positive for lysozyme, alpha-1-antitrypsin, alpha-1-antichymotrypsin, and vimentin. Electron microscopically, tumor cells showed a combination of fibroblastic and histiocytic features. The patient is currently well with no evidence of recurrence or metastasis 22 months after operation.

A new model of active specific immunotherapy using interleukin-1 and sonicated tumor supernatant in murine tumor system

The possibility of active specific immunotherapy using interleukin-1 (IL-1) plus sonicated tumor supernatant (SS) was examined in a murine tumor model. The growth of intraperitoneally or subcutaneously inoculated plasmacytoma MOPC104E, which is syngeneic to BALB/c mice, was significantly suppressed by intraperitoneal pretreatment with IL-1 and SS from MOPC104E cells (MOPC-SS), on days 10, 7, and 4 before tumor inoculation. Pretreatment with IL-1 plus MOPC-SS or MethA-SS (SS from MethA cells) suppressed the growth of subcutaneous tumor of only the corresponding tumor cells, indicating the development of tumor-specific immunity in vivo. The splenic cells of immunized mice with IL-1 and MOPC-SS showed tumor neutralizing activity. However, their tumor neutralizing activity was abrogated when they were treated in vitro with anti-Thy1.2 or anti-L3T4 plus complement. Moreover, when combined with indomethacin per oral, IL-1 plus MOPC-SS significantly suppressed the growth of established subcutaneous tumor and prolonged survival of post-operative mice. These results suggest that this new type of active specific immunotherapy could be a useful method for cancer immunotherapy, especially when combined with oral indomethacin.

Induction of antigen-specific cytolytic T cells in situ in human melanoma by immunization with synthetic peptide-pulsed autologous antigen presenting cells

Human melanoma cells can process the MAGE-1 gene product and present the processed nonapeptide EADPTGHSY on their major histocompatibility complex class I molecules, HLA-A1, as a determinant for cytolytic T lymphocytes (CTLs). Considering that autologous antigen presenting cells (APCs) pulsed with the synthetic nonapeptide might, therefore, be immunogenic, melanoma patients whose tumor cells express the MAGE-1 gene and who are HLA-A1+ were immunized with a vaccine made of cultured autologous APCs pulsed with the synthetic nonapeptide. Analyses of the nature of the in vivo host immune response to the vaccine revealed that the peptide-pulsed APCs are capable of inducing autologous melanoma-reactive and the nonapeptide-specific CTLs in situ at the immunization site and at distant metastatic disease sites.

Different contributions of cytochrome P450 2E1 and P450 2B1/2 to chloroform hepatotoxicity in rat

The contribution of cytochrome P450 isozymes CYP2E1 and CYP2B1/2 to chloroform-induced hepatotoxicity taken at 18 hr after the treatment was investigated in rats treated with n-hexane as an inducer of CYP2E1, 2-hexanone as an inducer of CYP2E1 and CYP2B1/2, and phenobarbital (PB) as an inducer of CYP2B1/2. Hepatic damage was evaluated by gross measurement of plasma alanine aminotransferase activity and histopathological examination. All treatments potentiated chloroform-induced hepatic damage. In n-hexane-pretreated rats, the damage was maximal with the middle dose of chloroform (0.2 ml/kg), whereas the damage increased with dose in rats treated with 2-hexanone or PB. The degree of hepatic damage induced with the three pretreatments was in the following order: n-hexane > 2-hexanone = PB with the middle dose of chloroform and PB >> 2-hexanone > n-hexane with the high dose (0.5 ml/kg); little difference among the pretreatments was seen with the low dose (0.1 ml/kg). These findings suggest that CYP2E1 is a low Km isoform and CYP2B1/2 a high Km isoform for chloroform activation. CYP2E1-dependent hepatic damage was characterized by ballooned hepatocytes, which were restricted to the centrilobular area; with CYP2B1/2, more necrotic than ballooned hepatocytes were seen and the necrotic hepatocytes were found not only in the centrilobular but also in the midzonal and periportal areas. Chloroform treatment did not affect the activity of N-nitrosodimethylamine N-demethylase in pretreated rats; the high dose increased the activity in control rats. In contrast, the high dose of chloroform decreased the activity of 7-pentoxyresorufin O-depentylase in all induced rats but not in controls. Immunoinhibition and immunoblot analyses showed that the high dose of chloroform induced CYP2E1 in control rats but decreased CYP2B1/2 in all pretreated rats. These results suggest that although both CYP2E1 and CYP2B1/2 contribute to chloroform-induced hepatic damage, they do so quite differently.

Presentation of synthetic peptide antigen encoded by the MAGE-1 gene by granulocyte/macrophage-colony-stimulating-factor-cultured macrophages from HLA-A1 melanoma patients

The recent identification of the sequences of the peptides derived from a number of human melanoma-associated antigens has presented opportunities for developing a specific-peptide-based vaccine in this form of cancer. Since antigen-presenting cells (APC) play a crucial role in the induction of the T-cell-mediated immune response, we examined whether or not ex vivo cultured APC, bearing the appropriate MHC restricting elements, when pulsed with a relevant melanoma-specific cytotoxic-T-lymphocyte (CTL)-determined peptide, can present the peptide to the CTL. Here we show that a population of cells, derived from the monocyte/macrophage lineage from peripheral blood and grown in granulocyte/macrophage-colony-stimulating factor, exhibit many essential characteristics of "professional" APC (dendritic-type morphology with a proportion of the population, the B7 molecule, and high levels of MHC class I and class II molecules, CD11b and CD54 molecules) and are capable of efficiently presenting the nonapeptide, EADPTGHSY, encoded by the melanoma antigen MAGE-1 gene, to the MAGE-1-specific CTL clone, 82/30. These results suggest that this type of autologous ex vivo cultured population of professional APC, when pulsed with the relevant-CTL-determined peptide, can serve as a novel type of candidate vaccine for active specific immunization against HLA-A1-positive patients with melanoma expressing the MAGE-1 antigen.

Three cases of extrapulmonary small cell carcinoma occurring in the prostate, stomach, and pancreas

Small cell carcinomas are fairly common neoplasms in the lung, but tumors featuring similar histological profiles may occur in extrapulmonary organs. Three cases of small cell carcinomas occurring in the prostate (case 1), stomach (case 2), and pancreas (case 3) are presented. Production of hormones was demonstrated immunohistochemically in all cases. In case 2 alpha-fetoprotein (AFP) was elevated in the serum and observed immunohistochemically in tumor cells. Production of AFP is a distinctive feature, which has not been reported in the pulmonary and extrapulmonary cases of small cell carcinoma. Amplification and/or expression of myc gene family have been suggested to be related to the prognosis of pulmonary small cell carcinoma. Amplification of myc genes was not detected in any of our cases, but c-myc protein was demonstrated immunohistochemically in tumor cells of case 1.