Histone deacetylase as a new target for cancer chemotherapy

Trichostatin A (TSA) and trapoxin (TPX), inhibitors of the eukaryotic cell cycle and inducers of morphological reversion of transformed cells, inhibit histone deacetylase (HDAC) at nanomolar concentrations. Recently, FK228 (also known as FR901228 and depsipeptide) and MS-275. antitumor agents structurally unrelated to TSA, have been shown to be potent HDAC inhibitors. These inhibitors activate the expression of p21Waf1 in a p53-independent manner. Changes in the expression of regulators of the cell cycle, differentiation, and apoptosis with increased histone acetylation may be responsible for the cell cycle arrest and antitumor activity of HDAC inhibitors. TSA has been suggested to block the catalytic reaction by chelating a zinc ion in the active site pocket through its hydroxamic acid group. On the other hand, an epoxyketone has been suggested to be the functional group of TPX capable of alkylating the enzyme. We synthesized a novel TPX analogue containing a hydroxamic acid instead of the epoxyketone. The hybrid compound, called cyclic hydroxamic-acid-containing peptide 1 (CHAP1) inhibited HDAC at low nanomolar concentrations. The HDAC1 inhibition by CHAPI was reversible, as is that by TSA, in contrast to irreversible inhibition by TPX. Interestingly, HDAC6, but not HDAC1 or HDAC4, was resistant to TPX and CHAP1, while TSA inhibited these HDACs to a similar degree. CHAP31, the strongest HDAC inhibitor obtained from a variety of CHAP derivatives, exhibited antitumor activity in BDF1 mice bearing B16/BL6 tumor cells. These results suggest that CHAP31 is promising as a novel therapeutic agent for cancer treatment, and that CHAP may serve as a basis for new HDAC inhibitors and be useful for combinatorial synthesis and high-throughput screening.

Cyclic hydroxamic-acid-containing peptide 31, a potent synthetic histone deacetylase inhibitor with antitumor activity

Cyclic hydroxamic-acid-containing peptide 1 (CHAP1), designed as a hybrid of trichostatin A and trapoxin, is a lead compound for the development of potent inhibitors of histone deacetylase (HDAC). In this study, we synthesized a series of CHAP derivatives and evaluated their biological activities by monitoring the potency of their inhibition of HDAC activity, their ability to augment the expression of MHC class-I molecules in B16/BL6 cells, and their effect on cell proliferation. A structure-activity relationship study using these three assay systems revealed several requirements of their structure for the strong inhibition of HDAC not only in the cell-free situation, but also in cells. When the structures of CHAP derivatives are represented as cyclo(-Asu(NHOH)-AA(2)-AA(3)-Pro or Pip-)(n), where Asu(NHOH) and Pip are zeta-hydroxamide-alpha-aminosuberic acid and pipecolic acid, respectively, (a) the tetrapeptide structure (n = 1) was better than the octapeptide one (n = 2); (b) AA(2) and AA(3) should be hydrophobic; and (c) the combination of amino acid chirality should be LDLD for the strongest inhibition of HDAC in cells (LDLD > LLLD, LDLL > LLDL). cyclo(-L-Asu(NHOH)-D-Tyr(Me)-L-Ile-D-Pro-) or CHAP31 was selected as one of the strongest CHAPs, and its biological activity was characterized further. CHAP31 was much more stable in the presence of cultured cells (t(1/2) > 3000 h) than trichostatin A (t(1/2) = 14.7 h) or trapoxin A (t(1/2) = 2.10 h). CHAP31 exhibited antitumor activity in C57BL x DBA/2 F(1) (BD2F(1)) mice bearing B16/BL6 tumor cells. Furthermore, CHAP31 inhibited the growth in four of five human tumor lines implanted into nude mice. These results suggest CHAP31 to be promising as a novel therapeutic agent for cancer treatment.

Crohn's disease of the esophagus: report of a case

We report herein the case of a 27-year-old man with Crohn's disease of the esophagus. The patient presented with large ulcers in the esophagus for which treatment based on a diagnosis of reflux esophagitis was commenced. Although his symptoms were initially resolved, the ulcers did not improve and he was readmitted to hospital 3 months later for progressive heartburn. An esophagoscopy revealed large ulcers in the esophagus, and a colonoscopy revealed a longitudinal ulcer in the terminal ileum. Histological examination of specimens from the terminal ileum showed severe inflammation without granuloma formation, which led to a diagnosis of Crohn's disease. The oral administration of prednisolone and salazosulfapyridine controlled his symptoms and the esophageal ulcers were observed to be healing 2 weeks after this treatment was initiated. A review of the English literature revealed only 77 cases of this disease. Isolated esophageal lesions were reported in ten patients (13.0%), none of which were able to be diagnosed as Crohn's disease preoperatively. Ileocolic lesions developed after esophageal lesions in only five patients (6.5%) including ours. In the remaining 62 patients (80.5%), ileocolic lesions had existed synchronous with or prior to the esophageal lesions. This suggests that ileocolic lesions may often coexist in Crohn's patients with esophageal lesions, and that examination of the terminal ileum must be performed to confirm a diagnosis of Crohn's disease of the esophagus.

Identification of endogenous ouabain in culture supernatant of PC12 cells

OBJECTIVE

Ouabain-like factor (OLF), assayed as ouabain-like immunoreactivity (OLI), is thought to represent an endogenous digitalis-like factor. We found increased plasma OLI during the surgical removal of a pheochromocytoma. The elution volume of the OLI extracted from plasma and the pheochromocytoma tissue was the same as that for authentic ouabain, using reverse phase high-performance liquid chromatography. The present study was performed to characterize OLF from the culture supernatant of a rat pheochromocytoma cell line, PC12 cells.

DESIGN

OLI from culture supernatant and chromatographic fractions were assayed by a sensitive enzyme-linked immunosorbent assay for ouabain. PC12 cells, subcultured in RPMI 1640 with 10% horse serum and 5% fetal bovine serum, were washed, and then cultured in Iscove's modified Dulbecco's medium (Life Technologies, Rockville, Maryland, USA) with 0.4% bovine serum albumin (without serum). Progesterone was added to augment the production or secretion of OLI. The conditioned medium was acidified to dissociate the binding protein, and OLI was purified by five steps of octadecylsilane (ODS) column chromatography. The structural identity of this OLI was determined by liquid chromatography and mass spectrometry (LC/MS).

RESULTS

OLI in the culture medium increased after addition of progesterone in a dose-dependent manner. The concentration in the culture medium was approximately double of that in homogenized PC12 cells. After five rounds of ODS column chromatography, approximately 100 ng of OLI was purified from 21 of culture supernatant, without fetal calf serum, in the presence of progesterone. The molecular size of purified OLI was found to be identical to authentic ouabain, based on analysis by LC/ MS.

CONCLUSION

Mammalian cells originating from a rat pheochromocytoma cell line were found to produce and/or secrete OLF by the addition of progesterone.

Expression of TMEFF1 mRNA in the mouse central nervous system: precise examination and comparative studies of TMEFF1 and TMEFF2

TMEFF1 and TMEFF2 are putative transmembrane proteins comprised of one epidermal growth factor (EGF)-like domain and two follistatin-like domains. Both TMEFF1 and TMEFF2 are predominantly expressed in the brain. We previously demonstrated that recombinant TMEFF2 protein can promote survival of neurons in primary culture and determined expression sites of TMEFF2 mRNA in the mouse central nervous system. To extend our understanding of TMEFF protein functions, we compared precise sites of expression of TMEFF1 and TMEFF2 mRNA using in situ hybridization analysis. Although both TMEFF genes are widely expressed in the brain, they exhibit different patterns of expression. TMEFF1 showed comparatively higher signals in the pyramidal cells of fifth layer of the cerebral neocortex, CA3, CA1 and subiculum regions of the hippocampus, locus coeruleus, and dentate cerebellar nucleus. In contrast, TMEFF2 is highly expressed in the medial habenular, CA2, CA3 and dentate gyrus region of the hippocampus, corpus callosum, cerebellar cortex and cranial nerve nuclei (III, IV, VII, X, XII). The results presented here indicate that expression of TMEFF1 and TMEFF2 are regulated differently and that they play region-specific roles in the central nervous system.

Potent histone deacetylase inhibitors built from trichostatin A and cyclic tetrapeptide antibiotics including trapoxin

Trichostatin A (TSA) and trapoxin (TPX) are potent inhibitors of histone deacetylases (HDACs). TSA is proposed to block the catalytic reaction by chelating a zinc ion in the active-site pocket through its hydroxamic acid group. On the other hand, the epoxyketone is suggested to be the functional group of TPX capable of alkylating the enzyme. We synthesized a novel TPX analogue containing a hydroxamic acid instead of the epoxyketone. The hybrid compound cyclic hydroxamic acid-containing peptide (CHAP) 1 inhibited HDAC1 at low nanomolar concentrations. The HDAC1 inhibition by CHAP1 was reversible as it was by TSA, in contrast to the irreversible inhibition by TPX. CHAP with an aliphatic chain length of five, which corresponded to that of acetylated lysine, was stronger than those with other lengths. These results suggest that TPX is a substrate mimic and that the replacement of the epoxyketone with the hydroxamic acid converted TPX to an inhibitor chelating the zinc like TSA. Interestingly, HDAC6, but not HDAC1 or HDAC4, was resistant to TPX and CHAP1, whereas TSA inhibited these HDACs to a similar extent. HDAC6 inhibition by TPX at a high concentration was reversible, probably because HDAC6 is not alkylated by TPX. We further synthesized the counterparts of all known naturally occurring cyclic tetrapeptides containing the epoxyketone. HDAC1 was highly sensitive to all these CHAPs much more than HDAC6, indicating that the structure of the cyclic tetrapeptide framework affects the target enzyme specificity. These results suggest that CHAP is a unique lead to develop isoform-specific HDAC inhibitors.

Relationship of p53 and vascular endothelial growth factor expression of clinicopathological factors in human scirrhous gastric cancer

Although scrirrhous cancer has the highest malignant potential among various types of gastric cancer, its pathogenesis is still unclear. The relationship between expression of p53 or vascular endothelial growth factor (VEGF) and clinicopathological variables was investigated by immunohistochemical analysis of archival specimens from 40 patients with scirrhous gastric cancer. Staining for p53 and VEGF was observed in the nuclei and cytoplasm of the tumor cells, respectively. There was no significant association between expression of p53 or VEGF and sex, age, depth of invasion, lymph node metastasis or histological stage. Peritoneal dissemination was the most frequent mode of recurrence, and the depth of tumor invasion was a crucial factor. The recurrence rate was 83.9% (2/9) in patients without serosal invasion. Only 7 out of 40 patients (17.5%) survived without recurrence. Among them, the VEGF-positive rate was 14.3% (1/7), whereas it was 52.6% (10/19) in the patients with recurrence. There was no correlation between p53 and VEGF staining. These findings suggest that the progression of scirrhous gastric cancer may be promoted by VEGF overexpression, which is not upregulated by p53 mutation.

Identification and characterization of TMEFF2, a novel survival factor for hippocampal and mesencephalic neurons

We have identified a novel mammalian gene, TMEFF2, that encodes a putative transmembrane protein containing two follistatin-like domains and one epidermal growth factor (EGF)-like domain. The TMEFF2 gene is predominantly expressed in the brain. In situ hybridization analysis revealed that TMEFF2 is widely expressed in the brain, including hippocampal cornu ammonis, dentate gyrus, and substantia nigra pars compacta. We evaluated the survival effect of TMEFF2 using primary cultured neurons from several regions of fetal rat brain following treatment with a recombinant TMEFF2 protein fragment consisting of the putative extracellular domain. TMEFF2 increased survival of neurons from the hippocampus and midbrain, but not from the cerebral cortex, indicating that the survival effects of TMEFF2 are specific to certain cell types. Recombinant TMEFF2 also promoted survival of mesencephalic dopaminergic neurons. Together, these findings suggest that TMEFF2 may be a novel survival factor for hippocampal and mesencephalic, but not for cortical, neurons.

Larger and more invasive colorectal carcinoma contains larger amounts of plasminogen activator inhibitor type 1 and its relative ratio over urokinase receptor correlates well with tumor size

BACKGROUND

Considering recent findings that both urokinase plasminogen activator receptor (uPAR) and plasminogen activator inhibitors (PAIs) are involved in tumor growth through an urokinase-type plasminogen activator (uPA) activity-independent mechanism, the relation between the presence of these factors in tumor tissue and the clinicopathologic variables in colorectal carcinoma was reevaluated.

METHODS

In 100 colorectal carcinoma patients, antigen levels of u-PA, uPAR, and PAI-1 and PAI-2 were assayed in both tumor tissues and their normal counterparts. Plasma levels of soluble uPAR also were determined.

RESULTS

All uPAR, uPA, PAI-1, and PAI-2 antigen levels in tumor tissue were significantly higher than those in normal tissue. Levels of both uPAR and PAI-1 were significantly higher (3.09 +/- 1.37 and 6.63 +/- 7.49, respectively) in large tumors (>/=50 mm in greatest dimension) than those in smaller tumors (< 50 mm) (2.50 +/- 1.07 and 2.72 +/- 2.70, respectively) (P < 0.05). Significant positive correlation coefficients (r) were obtained between tumor size and the calculated ratios of PAI-1/uPAR (r = 0.490; P < 0.0001) and PAI-1/uPA (r = 0. 469; P < 0.0001). In addition to liver metastases (P = 0.004) and lymph node involvement (P = 0.04), high levels of uPAR (P = 0.05) also were found to be of independent prognostic value by multivariate analysis.

CONCLUSIONS

Higher expression of uPAR was related to poor prognosis of patients with colorectal carcinoma and excess amounts of PAI-1 over uPAR or uPAR-bound uPA appeared to play an important role in tumor progression.

Primary structure of guinea pig plasma prekallikrein

A full length guinea pig plasma prekallikrein (PK) cDNA was cloned from a liver cDNA library. The nucleotide sequence with 2242 bp was analyzed and the amino acid sequence with 618 residues was deduced. Kallikrein was purified from guinea pig plasma and cleavage site in the activation was determined. The amino acid sequence around the cleavage site -368Ile-Asp-Ala-Arg-Ile-Val-Gly-375Gly- differed from that of the human PK -368Thr-Ser-Thr-Arg-Ile-Val-Gly-375Gly-. Protease substrates containing penta-peptides which mimicked the sequence of the cleavage sites from P3 to P2' of guinea pig Hageman factor (HF) and PK were synthesized, and kinetic analyses of the hydrolysis by guinea pig activated HF (HFa) and kallikrein were carried out. The combination between HFa and the PK mimicking peptide provided the best kinetics. These results in part explain why the cascade activation of PK by HFa is predominant in the guinea pig system.

Association study of a polymorphism of nonerythroid alpha-spectrin gene with schizophrenia

The specificity of cytoarchitectural abnormalities in limbic structures of patients with schizophrenia and their contributions towards the etiology of schizophrenia remain unknown. We have recently reported an increased breakdown of nonerythroid alpha-spectrin (fodrin), a major component of neuronal cytoskeletal proteins, in schizophrenic left superior temporal cortices [Kitamura et al., 1998: Biol Psychiatry 43:254-262], suggesting that polymorphisms of the alpha-spectrin gene might contribute to the vulnerability to schizophrenia. We screened for genetic variations associated with schizophrenia through the C-terminus sequences of the human nonerythroid alpha-spectrin gene (SPTAN1) spanning two EF-hands and also tested a possible contribution of the polymorphism to the development of schizophrenia by an association study. We found a polymorphic region of an intron located in the second EF-hand of SPTAN1 gene. There was no significant difference between patients with schizophrenia and controls in allele frequencies or genotype distribution. There is evidence that the Psh BI SPTAN1 gene polymorphism does not play a major role in the genetic component of schizophrenia.

In vivo L-band ESR and quantitative pharmacokinetic analysis of stable spin probes in rats and mice

Free radical species in animals have been measured by X-band ESR spectrometric method on a block of organs or a portion of homogenized samples. However, a nondestructive in vivo ESR measurement has been realized by using a recently developed L-band ESR spectrometry. With this L-band ESR method, we measured ESR spectra in animals, who received stable nitroxide radicals. L-band ESR spectra were observed at the upper abdomen of mice as well as at the heads of mice and rats at various ages immediately after the intravenous injections of nitroxide radicals such as 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl (4-hydroxy-TEMPO) and 3-carbamoyl-2,2,5,5-tetramethylpyrrolidine-1-oxyl (3-carbamoyl-PROXYL), in which ESR measurements of the radicals were performed noninvasively at the real time. On the basis of the observed time-dependent free radical clearance curves, the following important results were obtained: (1) Free radical clearances were able to analyze by the pharmacokinetic method. (2) The radicals at the head of mice, given 4-hydroxy-TEMPO, were determined quantitatively by a new analytical method using L-band ESR for the first time. (3) The elimination of the radical was found to be saturated in mice. (4) The clearance rate constant of 4-hydroxy-TEMPO detected at the head of mice was decreased in dose- and age-dependent manners. While, no age-dependent clearance rate constant of 4-hydroxy-TEMPO was observed at the upper abdomen of mice. (5) Ratios of the amount of the detected radicals to that of the administered radicals were decreased age-dependently, but they were independent of the dose of the radicals, suggesting the age-dependent decrease of distribution capacity ratio of the radical at the head of animals. (6) Clearance rate constants of 4-hydroxy-TEMPO and 3-carbamoyl-PROXYL, that were estimated by X- and L-band ESR for the collected blood of mice and rats, were found to be remarkably smaller than those in whole living animals observed by in vivo L-band ESR method. The results suggest that the clearance of the nitroxide radical is relevant to the alteration of the radical in animals following the change of organ distribution and metabolism. (7) Both the radical and its corresponding hydroxylamine, which is the reduced form of the radical, were detectable by X-band ESR method in the collected urine of mice and rats without and with an oxidizing agent, respectively. On the basis of the results on L-band ESR spectrometry, the first quantitative pharmacokinetic analysis of stable spin probes in animals is proposed.

Increases in plasma ouabainlike immunoreactivity during surgical extirpation of pheochromocytoma

The ouabainlike factor (OLF) is thought to be an important modulator of salt and water metabolism. Plasma OLF could be derived from the central nervous system and/or the adrenal gland. Since the adrenal medulla is of neural origin, the cytology of pheochromocytoma of adrenomedullary origin resembles that of neuronal cells. Ouabainlike immunoreactivity (OLI) is, in fact, present in the adrenal medulla as shown by immunohistochemistry. The plasma levels of catecholamines and OLI were significantly elevated during surgical extirpation of pheochromocytoma in this case. To clarify the origin of circulating OLI in a patient with pheochromocytoma, the relationship between plasma OLI and catecholamines during adrenalectomy was investigated. Plasma catecholamine levels exceeded the normal reference interval, and plasma OLI was positively correlated with the patient's plasma level of norepinephrine. The peak level during operation was about 10 times higher than the baseline level. Both levels reached a maximum when the tumor was mechanically pressed, and then gradually decreased thereafter. The level of OLI in the tumor was higher than that of the normal adrenal cortex. When OLI in the tumor was characterized by reversed-phase high-performance liquid chromatography, the retention time of OLI corresponded with that of authentic ouabain. These results suggest that the circulating OLI in this patients was derived mainly from the pheochromocytoma of adrenomedullary origin.

Induction of pseudopregnancy in the mongolian gerbil (Meriones unguiculatus) by vaginal stimulation

In rats, pseudopregnancy has been induced by mating with vasectomized males, by mechanical stimulation of the uterine cervix with a glass rod or vibrator, and by stimulation of the vagina with a tampon. On the other hand, no practical data are available in reports on the induction of pseudopregnancy in Mongolian gerbils. Pseudopregnancy of gerbils has been induced by mating with vasectomized males. But this method was uncertain because the incidence of pseudopregnancy was lower than that obtained in rats by other means. In the present study, two experiments were undertaken as follows. 1) Copulatory behavior of gerbils was observed for one hour to determine the most effective stimulation interval. 2) From the results of Experiment 1, female gerbils in estrus were mechanically stimulated to test the effectiveness of inducing pseudopregnancy by vaginal stimulation at various time intervals. The results of these experiments indicated that, although the frequency of copulatory behavior varied among individuals, on average the most effective method for inducing pseudopregnancy was stimulation of 5 min duration and at 20 or 30 min intervals. Because the incidence of pseudopregnancy induced by such mechanical stimulation (83.3%) was higher than that induced by mating with vasectomized males (30.0%), this method might be useful in inducing pseudopregnancy in Mongolian gerbils.

Long-term ambient ozone concentration and the incidence of asthma in nonsmoking adults: the AHSMOG Study

We conducted a prospective study of a cohort of 3091 nonsmokers, ages 27 to 87 years, to evaluate the association between long-term ambient ozone exposure and development of adult-onset asthma. Over a 15-year period, 3.2% of males and 4.3% of females reported new doctor diagnoses of asthma. For males, we observed a significant relationship between report of doctor diagnosis of asthma and 20-year mean 8-h average ambient ozone concentration (relative risk (RR)=2.09 for a 27 ppb increase in ozone concentration, 95% CI=1.03 to 4.16). We observed no such relationship for females. Other variables significantly related to development of asthma were a history of ever-smoking for males (RR=2.37, 95% CI=1.13 to 4.81), and for females, number of years worked with a smoker (RR=1.21 for a 7-year increment, 95% CI=1.04 to 1.39), age (RR=0.61 for a 16-year increment, 95% CI=0.44 to 0.84), and a history of childhood pneumonia or bronchitis (RR=2.96, 95% CI=1.68 to 5.03). Addition of other pollutants (PM10, SO4, NO2, and SO2) to the models did not diminish the relationship between ozone and asthma for males. These data suggest that long-term exposure to ambient ozone is associated with development of asthma in adult males.

Long-term inhalable particles and other air pollutants related to mortality in nonsmokers

Long-term ambient concentrations of inhalable particles less than 10 microm in diameter (PM10) (1973- 1992) and other air pollutants-total suspended sulfates, sulfur dioxide, ozone (O3), and nitrogen dioxide-were related to 1977-1992 mortality in a cohort of 6,338 nonsmoking California Seventh-day Adventists. In both sexes, PM10 showed a strong association with mortality for any mention of nonmalignant respiratory disease on the death certificate, adjusting for a wide range of potentially confounding factors, including occupational and indoor sources of air pollutants. The adjusted relative risk (RR) for this cause of death as associated with an interquartile range (IQR) difference of 43 d/yr when PM10 exceeded 100 microg/m3 was 1.18 (95% confidence interval [CI]: 1.02, 1.36). In males, PM10 showed a strong association with lung cancer deaths-RR for an IQR was 2.38 (95% CI: 1.42, 3.97). Ozone showed an even stronger association with lung cancer mortality for males with an RR of 4.19 (95% CI: 1.81, 9.69) for the IQR difference of 551 h/yr when O3 exceeded 100 parts per billion. Sulfur dioxide showed strong associations with lung cancer mortality for both sexes. Other pollutants showed weak or no association with mortality.

Possible role of alteration in pH, but not in ionic strength, in the modulation of Ca(2+)-dependent and diacylglycerol-induced association of protein kinase C-alpha with plasma membrane

In an attempt to elucidate the mechanism of the membrane binding of protein kinase C-alpha (PKC-alpha), effects of pH and ionic strength were examined on Ca(2+)-dependent and diacylglycerol-induced association of this PKC with rat liver plasma membrane. In the absence of diacylglycerol, the membrane-bound PKC-alpha increased according to the changes in pH from 6 to 8. However, these reactions were not seriously influenced by alterations in ionic strength (0-240 mM NaCl). In the presence of diacylglycerol, this pH-modulated binding of PKC-alpha to plasma membrane was more effective under lower Ca2+ concentration at pH 8. These results suggest that alkaline pH conditions seem to be important for preferable association of PKC-alpha with plasma membrane.

Solitary true cyst of the pancreas in two adults: analysis of cyst fluid and review of the literature

Solitary true cyst of the pancreas in adults is extremely rare. We report two adult cases of solitary true cyst of the pancreas. In a 53-yr-old woman there was discovered, incidentally, a unilocular cyst of 7.0 x 6.5 cm in size in the tail of the pancreas that was noted on abdominal US and CT scan. A 16-yr-old boy presented with abdominal pain, and an abdominal US and CT scan revealed a 6.5 cm cystic mass located in the tail of the pancreas. Both patients underwent distal pancreatectomy. Histologically, the cyst was lined with flattened cuboidal and squamous epithelium without morphological alterations. Analysis of the cyst fluid revealed high CA 19-9 (>100,000 U/L) and Span-1 levels (>60,000 U/L) in both cases. Immunohistochemically, the lining epithelial cells of true cyst were positive for CA 19-9 staining. The clinicopathological features of solitary true cyst of the pancreas in adults are briefly reviewed.

Multifocal serous cystadenoma of the pancreas. A case report and review of the literature

Serous cystadenoma of the pancreas is usually unifocal; multifocal tumors are rare. We report a case of multifocal serous cystadenoma of the pancreas in a 48-yr-old female complaining of general malaise. Serum tumor markers, such as CA 19-9, DUPAN-2, and Span-1, were elevated. Abdominal ultrasound (US) and computed tomography (CT) scans revealed two distinct cystic masses in the head and body of the pancreas, respectively. The patient underwent total pancreatectomy. The resected pancreas contained two discrete cystic masses in the head and body; no solid components were observed. Microscopically, the inner surfaces of the cysts were evenly lined by a single layer of low cuboidal or significantly attenuated epithelial cells containing clear cytoplasm and abundant glycogen without other morphological alterations. The histogenesis of serous cystadenoma is not clear; multicentric tumors may be helpful in understanding histogenesis.

Proliferative potential and K-ras mutation in epithelial hyperplasia of the gallbladder in patients with anomalous pancreaticobiliary ductal union

BACKGROUND

Recent studies have shown that anomalous pancreaticobiliary ductal union (APBD) is an important risk factor for the development of gallbladder carcinoma. Epithelial hyperplasia of the gallbladder is one of the characteristic changes, but it is not clear whether epithelial hyperplasia is a premalignant lesion that could lead to cancer in APBD patients.

METHODS

Twenty-four APBD patients were classified into two types: patients with bile duct dilation (dilated type) (n 13) and patients without dilation (undilated type) (n = 11). Resected gallbladders obtained from APBD patients and control patients without APBD were examined histologically and with immunohistochemical techniques for the detection of p53 and Ki-67 (as a cell proliferation marker). K-ras mutations were examined using polymerase chain reaction-restriction fragment length polymorphism and direct DNA sequence analysis. The patients were also classified, according to extent of epithelial hyperplasia, as having high grade or low grade hyperplasia.

RESULTS

Fifteen (63%) of 24 APBD patients had epithelial hyperplasia of the gallbladder, whereas no patients without APBD exhibited this lesion. The incidence of epithelial hyperplasia was significantly higher in the gallbladders of undilated-type APBD patients (91%) than in those of dilated-type patients (38%) (P < 0.01). Three of 24 APBD patients (13%) had gallbladder carcinoma, and 2 of the 3 gallbladder carcinomas (67%) were accompanied by diffuse epithelial hyperplasia of the gallbladder. Among 21 nonneoplastic gallbladders, diffuse epithelial hyperplasia was observed in all (100%) of the undilated-type APBD and in 4 (33%) of 12 dilated-type APBD (P < 0.001). High grade hyperplasia was observed in 7 of 11 patients (64%) with undilated-type APBD and 2 of 13 patients (15%) with dilated-type APBD (P < 0.05). The incidence of high grade hyperplasia increased with age among patients older than 35 years. Ki-67 labeling index (LI) was significantly higher in hyperplastic mucosa than in control gallbladder mucosa. High grade hyperplasia had a significantly higher Ki-67 LI than low grade hyperplasia (P < 0.001). Two (22%) of 9 high grade hyperplasia cases had K-ras mutations, whereas none of 6 low grade hyperplasia cases had. The types of K-ras mutations in codon 12 were GTT (Val) and GAT (Asp) in each case of hyperplasia; these were identical to those of concomitant carcinomas. Neither hyperplastic nor normal mucosa exhibited p53 overexpression.

CONCLUSIONS

The results of this study suggest that hyperplasia of the gallbladder mucosa in APBD patients is an early change that, because of the increased proliferative activity and presence of K-ras mutations, could be considered a premalignant lesion of the gallbladder. An increased cell population of epithelial hyperplasia may predispose the mucosa to mutational events, resulting in an increased risk for the development of gallbladder carcinoma in APBD patients.

Purification and characterization of ouabain-binding protein in human plasma

Ouabainlike factors are thought to be a kind of important modulators of salt and water metabolism in essential hypertension. We purified the binding-protein of ouabain (OBP) from human plasma. The amino-terminal sequence of OBP from human plasma, (NH2-TLGQPREPQVYTLPPXREEM-), indicated that OBP is the carboxy-terminal fragment (14.4 kDa by SDS-PAGE) from T218 of IgG2 heavy chain and from A221 of the IgG1 heavy chain constant region. Moreover, plasmin-cleaved Fc fragment (pFc) of IgG possessed the ouabain-binding activity by the gel-filtration method of pFc and authentic ouabain mixture, whereas neither intact, aggregate, nor papain-cleaved Fc fragment did. The amino-terminal sequence of pFc was NH2-THTXPPXPAPELLGGPXVFL-, and this sequence corresponded to the T105 to L125 fragment of the IgG1 heavy chain constant region. The growth of cultured THP-1 cells were arrested in the dose-dependent manner by ouabain, which was inhibited by the addition of 20 microg/mL of pFc. These results suggested that plasmin-cleaved Fc of human IgG is one of the binding protein of ouabain/ouabainlike factor(s) in human plasma.

Cloning and chromosomal mapping of a novel ABC transporter gene (hABC7), a candidate for X-linked sideroblastic anemia with spinocerebellar ataxia

We isolated a novel human ATP-binding cassette (ABC) transporter cDNA, determined its nucleotide sequence, and designated it human ABC7 (hABC7). The nucleotide sequence was highly homologous to the ATM1 gene in yeast, which encodes an ABC transporter (yAtm1p) located in the mitochondrial inner membrane. The deduced human product, a putative half-type transporter, consists of 752 amino acids that are 48.9% identical to those of yAtm1p. A computer-assisted protein structural and localization analysis revealed that the mitochondrial targeting signal of yAtm1p is conserved in the N-terminal region of the primary sequence of the hABC7 protein, and therefore this product is also likely to be located in the mitochondrial inner membrane. The evidence strongly suggests that the hABC7 gene is a counterpart of ATM1 and that its product is probably involved in heme transport. We mapped the hABC7 gene to chromosome Xq13.1-q13.3 by fluorescence in-situ hybridization. As band Xq13 has been implicated in X-linked sideroblastic anemia with spinocerebellar ataxia, hABC7 becomes a candidate gene for this heritable disorder.

Segmental groove pancreatitis accompanied by protein plugs in Santorini's duct

"Groove pancreatitis", a form of segmental pancreatitis affecting the head of the pancreas, is localized within the "groove" between pancreas head, duodenum, and common bile duct. Differentiation between groove pancreatitis and pancreatic head carcinoma is often difficult. We report a case of groove pancreatitis in which a hypoechoic mass between the duodenal wall and pancreas was clearly imaged, and narrowing of the second portion of the duodenum and bile duct stenosis were also found. The diagnosis was confirmed by surgery (pylorus-preserving pancreato duodenectomy). The patient was relieved from abdominal pain post operation. Up to the present, the patient has been good condition. We review the clinicopathologic and radiologic features of groove pancreatitis in the Japanese literature and discuss the possible role of Santorini's duct in its pathogenesis. We consider that impacted protein plugs in Santorini's duct are a pathogenic factor in the development of groove pancreatitis. Therefore, the findings of Santorini's duct on endoscopic retrograde pancreatography are very important in the diagnosis of groove pancreatitis. Groove pancreatitis presents various clinical features, such as biliary stenosis, duodenal stenosis, and pancreatic mass, and often masquerades as pancreatic head carcinoma. This condition should be kept in mind in the differential diagnosis of pancreatic head carcinoma.

[Measurement of levels of plasma endothelin-1 and serum nitrate anion in patients with sepsis]

Recently much attention has been paid to the circulatory disturbance and peripheral vascular damage in patients with sepsis and septic shock. We intended to elucidate the interaction between nitric oxide (NO) and endothelin (ET)-1 under various pathological conditions by measuring the concentrations of NO3-, the principal metabolite of NO and immunoreactive ET-1. In cases with good prognosis after the septic shock, ET-1 was significantly higher as compared with these in sepsis without shock. In lethal cases with septic shock, these parameters were abnormally high as compared with the survived case. These levels elevated as the degree of severity progressed. When patients recovered from the septic shock, plasma ET-1 levels rapidly decreased. These results may mean that the level of the concentration of ET-1 plays a key role for prevention of the multiple organ failure even after the recovery from septic shock. The elevated level of NO3- during the initial several days in septic shock will mean that NO is acting to prevent platelet aggregation and to keep blood flow by dilating the arteries during septic shock. On the contrary, it may also be suggested that the elevated level of NO3- and ET-1 leads to the dysfunction of vascular endothelial cells and the apoptosis.

Asymmetrical changes in the fodrin alpha subunit in the superior temporal cortices in schizophrenia

BACKGROUND

We examined possible abnormalities in neural structural proteins that may underlie morphometric changes reported in the left superior temporal cortices (Brodmann's area 22) of schizophrenics.

METHODS

Particulate proteins of the superior temporal cortices taken at autopsy from 11 schizophrenic and 9 control brains were fractionated by gel electrophoresis. Target proteins, identified by reading their amino acid sequences, were immunoquantified using the specific antibody.

RESULTS

Amino acid sequences of the 150-kDa proteins on sodium dodecyl sulfate/polyacrylamide gel electrophoresis, which were significantly increased on the left side of schizophrenic superior temporal cortices, revealed that they were proteolytic fragments of the alpha subunit of fodrin, a major cytoskeletal protein underlying the plasma membrane. Immunoquantification using the specific antibodies against alpha and beta subunits of fodrin indicated that there exist concomitant decreases in the full-length 240-kDa form and increases in the 150-kDa form of alpha-fodrin with no changes of the 235-kDa form of beta-fodrin in the left superior temporal cortices of the schizophrenic brains.

CONCLUSIONS

The findings may be a possible molecular basis for linking morphometric changes to neurochemical pathophysiology in schizophrenia.

Selective cytotoxicity of farnesylamine to pancreatic carcinoma cells and Ki-ras-transformed fibroblasts

Farnesyl protein transferase (FPTase) catalyses the post-translational modification of proteins by a farnesyl pyrophosphate. One of the substrates of this enzyme is p21ras, the product of the ras oncogene. We examined whether farnesylamine, one of the FPTase inhibitors (FTI), is selectively cytotoxic in pancreatic carcinoma cells and Ki-ras-transformed fibroblasts. Furthermore, we investigated whether the cytotoxicity of farnesylamine is caused by the induction of apoptosis in these cells. Using the FPTase assay, we found that farnesylamine inhibited FPTase in vitro. Immunoprecipitation showed that farnesylamine inhibited farnesylation of p21ras in vivo. In addition, 24 and 5 microM farnesylamine were required to achieve 50% cytotoxicity in pancreatic carcinoma cells containing activated Ki-ras and Ki-ras-transformed NIH/3T3 cells, respectively. The parental NIH/3T3 cells were resistant to the cytotoxic effect of farnesylamine at concentrations less than 100 microM. After incubation with farnesylamine, DNA fragmentation was observed in both pancreatic carcinoma cells and Ki-ras-transformed fibroblasts at cytotoxic doses of this compound but not in NIH/3T3 cells. These results indicate that the mechanism of cell death induced by farnesylamine is apoptosis, and this apoptosis occurred specifically in pancreatic carcinoma cells containing mutated Ki-ras and the Ki-ras-transformed cells. Because raf is downstream of ras (p21ras) in the ras-raf-mitogen-activated protein kinase signaling pathway, we used c-raf-1-transformed fibroblasts, which proved to be resistant to apoptosis induced by farnesylamine. This supports the theory that inhibition of ras signaling may be related to the induction of apoptosis. These data further suggest that farnesylamine could be useful as a chemotherapeutic agent in cancers that very frequently contain a Ki-ras oncogene mutation, e.g., pancreatic cancer.

Association between anomalous pancreaticobiliary ductal union and adenomyomatosis of the gall-bladder

A frequent association of biliary tract carcinoma and anomalous pancreaticobiliary ductal union (APBD) is well recognized, especially gall-bladder carcinoma in undilated type APBD. However, little is known about the presence and incidence of adenomyomatosis (AMT) of the gall-bladder, a presumed premalignant lesion, in patients with APBD. This retrospective study was conducted to elucidate the clinical features and incidence of AMT in APBD patients with relation to undilated type and dilated type APBD. We reviewed the clinicopathological records of 30 patients with APBD (28 women and two men) encountered during the past 10 years. Among them, 22 patients underwent cholecystectomy and the resected specimens were subjected to histopathological examinations. Eleven cases of APBD patients were undilated type and 11 cases were dilated type. Adenomyomatosis was found in six (55%) of 11 undilated type and one (9%) of 11 dilated type, and fundal type was predominantly observed in six (86%) of seven AMT. An overall incidence of AMT in APBD patients was 32%. An undilated type of APBD is frequently associated with AMT and we believe, therefore, that clinicians should be aware of a possible coexistence of APBD and AMT.

Isotype-specific G protein abnormalities in the left superior temporal cortex and limbic structures of patients with chronic schizophrenia

BACKGROUND

The potential role of signal transducing guanine nucleotide-binding regulatory protein (G protein) in schizophrenia is largely unknown.

METHODS

We immunoquantified isotypes of G protein using specific antisera against alpha and beta subunits of G protein in the superior temporal, prefrontal, and entorhinal cortices as well as the nucleus accumbens and amygdala of postmortem brains from 19 schizophrenic and 28 control subjects.

RESULTS

In the left hemisphere of schizophrenics, the amount of Gi alpha, Go alpha, and Gq alpha but not that of Gs alpha or G beta decreased in the superior temporal cortex by 27%, 27%, and 16%, respectively, as compared with the values in ipsilateral controls; the amount of any G protein isotype in the prefrontal and entorhinal cortices was not changed. In the nucleus accumbens and amygdala, the paranoid type schizophrenics showed a smaller amount of Gi alpha and Go alpha than the disorganized type schizophrenics. In the right superior temporal cortex, the isotype amount did not differ between the schizophrenic and control groups.

CONCLUSIONS

The decreased Gq alpha immunoreactivity in the schizophrenic left superior temporal cortex may reflect the down-regulation of Gq alpha, resulting from chronic stimulation of Gq alpha-coupled receptors, while the decreased Gi alpha and Go alpha in the nucleus accumbens and amygdala of paranoid type schizophrenics may be related to the dopaminergic hyperactivity via dopamine D2 receptors.

Thickened inner hypoechoic layer of the gallbladder wall in the diagnosis of anomalous pancreaticobiliary ductal union with endosonography

BACKGROUND

An anomalous pancreaticobiliary ductal union (APBD) is a high-risk factor for biliary tract carcinoma, which often is not diagnosed before overt malignancy. The early detection of APBD is therefore clinically important. We evaluated the gallbladder wall in APBD patients with endoscopic ultrasonography.

METHODS

Clinicopathologic features and ultrasonographic findings of the gallbladder in 33 consecutive patients with APBD between 1986 and 1995 were studied in relation to two subtypes of APBD, that is, undilated (n = 17) and dilated (n = 16). The gallbladder wall was evaluated with conventional ultrasonography and/or endoscopic ultrasonography. Histologic examinations of 25 resected gallbladders were made.

RESULTS

Fourteen of the seventeen patients with undilated type APBD (82%) had diffuse thickened gallbladder wall of 4 mm or more, whereas 5 of the 16 with dilated type (31%) had this finding (p < 0.01). The thickened gallbladder wall consisted sonographically of two layers: diffuse thickened inner hypoechoic layer and outer hyperechoic layer. Mucosal hyperplasia was histologically found in 8 of 9 cases (89%) with thickened inner hypoechoic layer on endoscopic ultrasonography. Mucosal hyperplasia was observed in 10 of 11 undilated type APBD cases (91%) in which cholecystectomy was performed. In addition, the presence of anomalous union was shown by endoscopic ultrasonography in 9 of 11 patients with undilated type APBD (82%) and all 7 of those with dilated type. The characteristic ultrasonographic pattern of diffuse thickened inner hypoechoic layer was observed exclusively in patients with mucosal hyperplasia of the gallbladder associated with APBD among 2085 endoscopic ultrasonography examinations performed during the study period.

CONCLUSIONS

Diffuse thickened inner hypoechoic layer of the gallbladder wall was frequently observed in APBD patients, especially those with the undilated type, on ultrasonography and/or endoscopic ultrasonography. This finding corresponded histologically to mucosal hyperplasia of the gallbladder mucosa. Thickened inner hypoechoic layer is a useful ultrasonographic sign that indicates mucosal hyperplasia of the gallbladder and, particularly, the possible coexistence of undilated type APBD before the appearance of overt malignancy.

p53 overexpression and proliferative activity do not correlate with lymph node metastasis in early gastric cancer

We investigated p53 overexpression and the proliferative activity of the primary lesion as well as the clinicopathological features of 75 patients with gastric cancer invading the submucosa (sm cancer), of whom 14 (18.7%) had lymph node metastasis. Among the clinicopathologic features studied, only lymphatic invasion by the primary tumor was related to lymph node metastasis. There was no relationship between immunohistochemical staining for p53 protein or Ki-67 and lymph node metastasis. The p53-positive rate was 35.7 and 57.1% in patients with and without metastasis, respectively, while the mean Ki-67 labeling index was 38.9 and 38.1%, respectively. Our results suggest that p53 mutation or the proliferative activity of sm cancer do not influence lymph node metastasis, even though p53 mutation may enhance the proliferative activity and metastatic potential of advanced gastric cancer.

Measurement of pancreatic blood flow to prevent pancreatic juice leakage after pancreas-preserving total gastrectomy for gastric cancer

In patients with gastric cancer, distal pancreatectomy was frequently performed for complete removal of the lymph nodes along the splenic artery, but this procedure sometimes induced pancreatic juice leakage, subphrenic abscess, and postoperative diabetes. To avoid these complications, pancreas-preserving total gastrectomy (PP) was developed by Maruyama et al. [World J Surg 1995; 19:552-536], with which the spleen, splenic artery, and fatty connective tissue including lymph nodes could be removed completely without distal pancreatectomy. From 1988 to 1995, 36 patients underwent PP in our department. Although there were no operative deaths and no patient developed postoperative diabetes, pancreatic juice leakage was observed in 4 patients (11.1%). We assumed that ischemia of the distal pancreas may have caused this pancreatic juice leakage and investigated the relationship between pancreatic blood flow (PBF) and this complication in 12 recent patients. A significant negative correlation between PBF in the pancreatic tail and the peak amylase level (PAL) in the drain fluid was demonstrated. Two patients with PBF values of 4.5 and 5.2 ml/min/100 g tissue, respectively, and a PAL of more than 2 x 10(5) U/l developed pancreatic juice leakage, whereas the 10 patients without this complication had PBF values above 6 ml/min/100 g tissue and a PAL of less than 2 x 10(4) U/l. These results suggest that measurement of PBF may be useful to predict the leakage of pancreatic juice after PP and that distal pancreatectomy may be preferable when PBF is extremely low.

Study on the estrous cycle in the Mongolian gerbil (Meriones unguiculatus)

The paucity of information and the unagreed consensus about the estrous cycle of the Mongolian gerbil (Meriones unguiculatus) have rendered such studies rather difficult. The estrous cycle of the Mongolian gerbils in this report were divided into 5 stages: Stage I, proestrus; Stage II, estrus (scattering); Stage III, estrus (gathering); Stage IV, metestrus and Stage V, diestrus. The normal estrous cycle in the Mongolian gerbils was 4-6 days long. In our experimental conditions, 67.9% of virgin females had a 4-6 day cycle, whereas 26.4% had an unsettled cycle and 5.7% assumed pseudopregnancy. The changing pattern of the estrous cycle and copulatory behavior of the Mongolian gerbils after hormone (PMSG: pregnant mare serum gonadotropin, 10 IU; hCG: human chorionic gonadotropin, 10 IU) injection were examined. The change in the estrous stage after hormone injection could be roughly classified into two types. The vaginal smear of virgin females injected with PMSG at Stage I, II or III changed to Stage V the next day and to Stage I or Stage II after 48 hr, but in the case of Stage IV or V, the smear changed to Stage I after 48 hr. The females injected with PMSG at Stage I, II or III copulated at from 13:00 to 23:00, whereas others injected at Stage IV or V scarcely copulated at all between 13:00 and 23:00. Mating of these females with the male midnight was not observed.

Synchronous lymphoma and adenocarcinoma occurring as a collision tumor in the stomach: report of a case

We report herein the rare case of a 71-year-old man who was initially operated on under the diagnosis of advanced gastric cancer, but was subsequently found to have synchronous lymphoma and early adenocarcinoma of the stomach, confirmed by postoperative pathological examination. The patient had a history of lymphoma of the left tonsil, and histologically the gastric lymphoma was observed to be of the non-Hodgkin's, diffuse, large-cell type. Conversely, the gastric cancer was early well-differentiated tubular adenocarcinoma of type 0-IIa, according to the Japan Gastroenterological Endoscopy Society classification. The two tumors had collided at the fornix. The relationship between these two tumors is analyzed and the most appropriate methods of diagnosis and treatment are discussed.

Increased striatal glutamate transporter by repeated intermittent administration of methamphetamine

We have examined the immunoreactivities of a glutamate (Glu) transporter, GLT-1, in rat brains treated with a single or repeated intermittent administration of methamphetamine (MAP). In the stratum of behaviorally sensitized rate induced by repeated intermittent MAP treatment, GLT-1 immunoreactivities were increased by 51%. There was no difference in the GLT-1 immunoreactivities in all regions examined between rate treated with a single administration of MAP and the control rats. These results suggest that hyperglutamatergic activity in the striatum is involved in the induction of behavioral sensitization caused by MAP.

Tandem enzymatic resolution yielding L-alpha-aminoalkanedioic acid omega-esters

The tandem action of serine protease (alpha-chymotrypsin or subtilisin BPN') and Aspergillus genus aminoacylase on racemic N-acetyl-alpha-aminoalkanedioic acid alpha,omega-diester produced L-alpha-aminoalkanedioic acid omega-ester in good yield and high optical purity. L-alpha-Aminosuberic acid omega-ester thus obtained was conveniently introduced into an oxytocin analog, [Asu1,6]oxytocin, by the solid-phase-synthesis and cyclization-cleavage method with oxime resin.

Delayed changes in neural visinin-like calcium-binding protein gene expression caused by acute phencyclidine administration

Phencyclidine (PCP) induces a psychotomimetic state that closely resembles schizophrenia, and PCP-treated animals can serve as a model for schizophrenia. The effects of PCP on the gene expression of NVP-1, a novel Ca(2+)-binding protein, were studied in rats. After 24 hours, the NVP-1 mRNA level in the nucleus accumbens showed a significant decrease of 42%. This result suggests that alterations in Ca(2+)-binding protein may be involved in the pathology of PCP-induced psychosis and, presumably, schizophrenia.

Substrate specificity of rabbit liver metalloendopeptidase and its new fluorogenic peptide substrates

A metalloendopeptidase (MEP) isolated from rabbit liver microsomes with substrate specificity for peptides containing Arg at the P1 and P4 positions has recently proved to be identical to soluble angiotensin-binding protein present in the cytosol. Here we describe the peptide-degrading specificity of MEP, determined using various bioactive peptides and novel fluorogenic substrates for the enzyme. MEP degraded oligopeptides, including bradykinin, alpha-neoendorphin, bovine adrenal medulla dodecapeptide, substance P, bombesin, neurotensin, and alpha-endorphin, but not polypeptides such as reduced lysozyme and histone H4, hence, MEP probably belongs to the family of endo-oligopeptidases. It cleaved most preferentially at the -Phe-Ser- bond of bradykinin (kcat/Km = 2.8 x 10(4) M-1.S-1) but did not cleave high molecular weight and low molecular weight kininogens, the precursors of bradykinin. MEP did not cleave angiotensin I, dynorphin A 1-13, somatostatin, and luteinizing hormone-releasing hormone, some of which are good substrates for metalloendopeptidase-24.15, metalloendopeptidase-24.16, N-arginine dibasic convertase, and yeast endopeptidase-24.15 related peptidase. An active site-directed inhibitor of metalloendopeptidase-24.15, N-[1-(R,S)-carboxyl-3-phenylpropyl]-Ala-Ala-Phe-p-aminobenzoate also had no effects on the amidolytic activity of MEP. Based on the cleavage sites of bioactive peptides and processing sites of vitamin K-dependent proproteins, intramolecularly quenched fluorogenic peptide substrates were newly synthesized. Among the thirteen substrates used, the most reactive was 2-aminobenzoyl-Ala-Arg-Val-Arg-Arg-Ala- Asn-Ser-2,4-dinitroanilinoethylamide (kcat/Km = 9.3 x 10(5) M-1.S-1). An angiotensin antagonist, [Sar1, Ala8]-angiotensin II, inhibited hydrolysis of the substrate by MEP in a competitive manner (Kl = 7.6 microM). MEP cleaved oligopeptides even on the carboxyl side of proline residue and these peptides are resistant to hydrolysis by the cytosol-derived proteasome, therefore MEP may participate in the catabolism of oligopeptides in the cytosol, together with other endo-oligopeptidases.

[Postoperative abdominal lymph node recurrence of intrathoracic esophageal cancer with a long-term complete response to radiation and split CF therapy (CDDP and 5-FU)--a case report]

We experienced complete remission in a patient with postoperative abdominal lymph node recurrence of intrathoracic esophageal cancer after treatment with radiation (60Co: 30 Gy) and split CF therapy (CDDP: 20 mg/day + 5-FU: 1 g/day for 5 days). Since then, this patient has remained in complete remission for 43 months with intermittent split CF therapy one or two times a year.

A case of triple early gastric cancer in the remnant stomach

A 63-yr-old man, who had undergone distal gastrectomy and gastrojejunostomy (Billroth II method) 32 yr previously for duodenal ulcer, was admitted with suspected gastric remnant cancer. An upper gastrointestinal series and endoscopy revealed a protruding lesion at the stoma of the remnant stomach. Total gastrectomy with resection of the adjacent jejunum was performed. Histological examination demonstrated two well-differentiated adenocarcinomas (a mixed type I and IIc lesion with submucosal invasion and a type IIa lesion with intramucosal invasion) and a type IIc mucocellular carcinoma located in the mucosa. Gastritis cystica polyposa also was observed in the remnant stomach. The combination of three early gastric cancers and gastritis cystica polyposa suggests that the mucosa of the remnant stomach had a high malignant potential. The patient has survived without recurrence for 5 yr since the operation.

Hepatocyte growth factor as a hematopoietic regulator

Hepatocyte growth factor (HGF) was originally isolated as a mitogen for adult hepatocytes, but this cytokine is now regarded as a multi-functional factor. In the present study, we show that the mouse liver in the middle and/or late stage of the fetal life expresses both HGF and c-met (its receptor) messages. HGF and c-met mRNA are coexpressed not only in the adherent layers of fetal liver long-term cultures (FL-LTCs) and adult bone marrow long-term cultures (BM-LTCs), but also in the stromal cell lines MS-5 and PA-6. Addition of human HGF (2 and 20 ng/mL) to the LTCs enhances (1) nonadherent cell counts (ninefold in FL-LTCs and sixfold in BM-LTCs), (2) nonadherent colony-forming unit-in culture (CFU-C) counts (eightfold in FL-LTCs and fivefold in BM-LTC), and (3) cobblestone colony counts. However, HGF slightly inhibits the proliferation of stromal cells. No direct effect of HGF on freshly isolated BM and/or FL cells is found in the CFU-C assay. However, an approximately 1.5-fold synergistic increase in CFU-C counts is noted when the BM or FL cells are cocultured with HGF in the presence of interleukin-3. These findings strongly suggest that HGF plays a crucial role as a hematopoietic regulator in the proliferation and differentiation of hematopoietic progenitors.

Comparison of the inhibitory effect of the angiogenesis inhibitor, TNP-470, and mitomycin C on the growth and liver metastasis of human colon cancer

Angiogenesis inhibitors have attracted considerable interest. The anti-tumor and anti-metastatic effects of TNP-470, an angiogenesis inhibitor, and mitomycin C (MMC), a representative anti-neoplastic agent, were investigated using a xenotransplanted human colon cancer, TK-4. Suturing of small pieces of TK-4 tumors to the cecal wall in nude mice (orthotopic transplantation) induced liver metastasis. Mice were randomly divided into 3 groups; a control group given saline solution, a group receiving TNP-470 and a group receiving MMC. TNP-470 was given s.c. on alternate days for 5 weeks from day 10 after cecal transplantation and MMC was administered intraperitoneally (i.p.) once a week from day 10 after cecal transplantation. MMC significantly inhibited cecal tumor growth. In the control group, liver metastases developed in 9 out of 10 mice, including 3 with more than 20 metastatic foci. Liver metastasis also developed in 8 out of 10 mice receiving MMC, 2 of which had many metastases. In contrast, liver metastasis developed in only 2 out of 8 mice in the TNP-470 group and neither of these animals had numerous metastases.

DNA analysis in hereditary dentatorubral-pallidoluysian atrophy: correlation between CAG repeat length and phenotypic variation and the molecular basis of anticipation

Hereditary dentatorubral-pallidoluysian atrophy (DRPLA) is an autosomal dominant neurodegenerative disease with variable clinical phenotypes. Progressive ataxia, choreoathetosis, and dementia are the main clinical features of adult-onset cases, whereas the main feature in juvenile-onset DRPLA is progressive myoclonus epilepsy. Earlier onset is apparent in successive generations (anticipation). The molecular abnormality underlying DRPLA is an expanded, unstable CAG trinucleotide repeat on chromosome 12p. We analyzed 71 DNA samples obtained from 12 Japanese DRPLA pedigrees that included 38 affected individuals. Normal alleles had 7 to 23 repeats, DRPLA alleles 53 to 88 repeats. DRPLA alleles also were detected in five asymptomatic family members. Patients with juvenile onset had significantly larger repeats than did those with adult onset, and there was a significant negative correlation between CAG repeat length and age at onset. In 80% of the paternal transmissions, there was an increase of more than five repeats, whereas all the maternal transmissions showed either a decrease or an increase of fewer than five repeats. There was a significant correlation between father-child differences in repeat length and differences in age at onset. The analysis of CAG repeat length is a reliable diagnostic test for DRPLA and is of value for the presymptomatic detection of individuals at risk. The expansion of CAG repeats is important in phenotypic variation and anticipation. In addition, the sex of the transmitting parent has a significant effect on the molecular mechanism of anticipation.

Postoperative changes in plasma tissue-type plasminogen activator and type 1 plasminogen activator inhibitor

To clarify the changes which occur postoperatively in intravascular fibrinolysis, plasma levels of tissue-type plasminogen activator (t-PA) antigen, the total plasminogen activator inhibitor type-1 (PAI-1) antigen, and the t-PA-PAI-1 complexes were assayed in this study. Blood samples were taken the morning before surgery, then at 0, 12, 24, 36, 60, 108, and 156 h postoperatively in ten patients who underwent radical surgery for thoracic esophageal cancer. The plasma levels of the t-PA and total PAI-1 antigens, and the t-PA-PAI-1 complexes were then measured by enzyme immunoassay. The plasma t-PA and total PAI-1 levels increased significantly in the immediate postoperative period, the percent increase of the latter being much greater than that of the former. Moreover, the calculated free t-PA antigen level was decreased throughout the postoperative period, suggesting postoperative hypofibrinolysis. The platelet count and neutrophil elastase level were significantly correlated with the free t-PA antigen level at r = 0.630, P < 0.001, and r = -0.447, P < 0.01, respectively. The results of this study indicated that post-operative hypofibrinolysis caused by the increased synthesis of PAI-1 may enhance postoperative hypercoagulability, and this may lead to the development of organ damage. Thus, the concentration of the PAI-1 antigen may be a potentially important index for the prediction of postoperative illness.

Suppression of polymorphonuclear leucocyte chemotaxis by Pseudomonas aeruginosa elastase in vitro: a study of the mechanisms and the correlation with ring abscess in pseudomonal keratitis

Bacteria, or the culture supernatants of an elastase non-producing strain of Pseudomonas aeruginosa, elicited a chemotactic response from polymorphonuclear leucocytes (PMN) in vitro. The chemoattractive capacity was diminished under the presence of Boc-Phe-Leu-Phe-Leu-Phe, a receptor antagonist of N-formyl-Met-Leu-Phe (fMLP) which is a bacterial chemotactic peptide to PMN. This indicated that the chemoattractant derived from Pseudomonas aeruginosa was a fMLP-like molecule(s). In contrast, culture supernatants of an elastase producing strain of Pseudomonas aeruginosa produced negligible chemotactic response from PMN. Indeed, an inhibitory effect of the culture supernatants or of purified Pseudomonas aeruginosa elastase (PAE) on PMN chemotaxis was observed when fMLP was used as a chemoattractant. Another fMLP-induced function of PMN, respiratory burst activation, was also diminished by pretreatment of PMN with PAE. PAE hydrolysed fMLP at the Met-Leu bond and diminished the chemoattractant capacity. In addition, a receptor analysis with fML-3H-P demonstrated a decrease in numbers of fMLP receptors on PMN without changing the dissociation constant values after the treatment of the cells with PAE. In the primary structure of the fMLP receptor previously reported, a preferential amino acid sequence for cleavage by PAE was identified in what was believed to be an extracellular portion of the receptor molecule. These results suggested that PAE could diminish PMN infiltration in response to Pseudomonas aeruginosa in vivo by cleavage of the fMLP-like pseudomonal chemotactic ligand and the receptors on PMN.

Identification of EGF as an angiogenic factor present in conditioned medium from human salivary gland adenocarcinoma cell clones with varying degrees of metastatic potential

We have previously shown that conditioned medium (CM) from metastasizing human salivary gland adenocarcinoma cell clones contains factor(s) that stimulate the proliferation and migration of bovine aortic endothelial (BAE) cells, and inhibit the production of collagenases by BAE cells (Azuma M. et al. (1993) Cancer Lett., 73, 85-93). To further characterize this, we evaluated the expression level of epidermal growth factor (EGF) secreted by a non-metastasizing cell clone (HSGc) and its metastasizing cell clones, and analysed the effect of EGF on the biologic behaviors of BAE cells. When the secretion of EGF by cell clones was estimated by enzyme-linked immunosorbent assay, metastasizing cell clones released a large amount of EGF as compared with HSGc. However, the number of EGF receptor was detected consistently at a level that was similar in all cell clones. With regard to the effect of EGF on the malignant potential of cell clones such as proteolytic aggressiveness, EGF did not affect the secretion of both collagenases and their inhibitor from cell clones. Alternatively, exogenous EGF stimulated the proliferation and migration of BAE cells, and inhibited the secretion of collagenases from BAE cells. Neutralization with a neutralizing antibody of EGF released into CM abolished the inhibitory effect of CM on the secretion of collagenases from BAE cells. Thus, the CM-contained factor, which is responsible for the induction of biologic behaviors of BAE cells, can be attributed to EGF.