Cytomorphologic features characteristic of tumor stages of thymomas

The cytologic findings of the tumor cells characteristic of the stages of thymomas were investigated to assess the invasiveness of the tumors. Forty-six patients with thymoma who underwent extensive thymectomy without pre-operative corticosteroid therapy were included in this study. The histologic subtypes included 18 round/oval, 20 mixed, and 8 spindle type. The stages of thymoma classified according to Masaoka's clinicopathological classification included 16 stage I, 20 stage II, 6 stage III, 2 stage IVa, and 2 stage IVb, and myasthenia gravis was recognized in 5 patients. Cytologic findings were retrospectively analyzed in the Papanicolaou-stained stamp smears obtained from the cut surfaces of thymoma specimens. Morphometry of the epithelial tumor cells using Cosmozone-1A was performed to evaluate the validity of our cytologic categories. Compared with the cytologic findings of stage I or II thymomas, those of epithelial tumor cells in stage III or IV more frequently showed necrotic background (50.0%-stage III or IV vs 11.1%-stage I or II, p=0.006), large clusters of epithelial tumor cells (70.0% vs 36.1%, p=0.055), marked nuclear enlargement (90.0% vs 52.7%, p=0.033), marked anisokaryosis (100% vs 52.7%, p=0.006), marked nuclear polymorphism (40.0% vs 5.5%, p=0.004), hyperchromasia (50.0% vs 11.4%, p=0.007) and prominent nucleoli (50.0% vs 16.6%, p=0.028) whereas no significant correlation was observed between cytologic findings and tumor volume. Morphometric studies of thymoma tumor cells revealed that the nuclear size (mean values, 78.8 microm(3)-stage III or IV vs 58.2 microm(3)-stage I or II), the coefficient of variation of the nuclear size (0.326 vs 0.282), and the nuclear rotundity (0.849 vs 0.858) differed significantly between the two categories (p<0.05). Our findings demonstrated that there were significant differences between the cytologic findings of epithelial tumor cells of stage I or II thymomas and those of stage III or IV thymomas, and that the cytologic findings of thymoma tumor cells appear to be useful for distinguishing between non-invasive and invasive thymomas.

Anti-HIV-1 activity and structure-activity relationship of cepharanoline derivatives in chronically infected cells

Cepharanthine (12-O-methyl cepharanoline) is a plant alkaloid and has been shown to inhibit tumour necrosis factor-alpha- or phorbol 12-myristate 13-acetate-induced HIV-1 replication in the chronically infected promonocytic cell line, U1. Its mechanism of action is considered to be the inhibition of nuclear factor kappaB, a potent inducer of HIV-1 gene expression. In this study, we have synthesized 96 derivatives of cepharanoline, including cepharanthine, and examined their inhibitory effects on HIV-1 replication in U1 cells. Among the 12-O-alkyl derivatives, cepharanthine proved to be the most active, and the activity decreased as the length of the alkyl chain increased. All of the 12-O-acyl derivatives were totally inactive, while a few 12-O-carbamoyl derivatives displayed modest activity. Since 12-O-ethyl derivatives were found to be as active as cepharanthine against HIV-1 replication, we further synthesized various 12-O-ethyl derivatives of cepharanoline. Among the derivatives, five proved to be more active inhibitors than cepharanthine, and the most active compound was 12-O-ethylpiperazinyl cepharanoline. The 50% effective concentrations of this compound and cepharanthine were 0.0041 and 0.028 microg/ml (0.0060 and 0.046 microM), respectively.

Sensory potentials evoked by tactile stimulation of different indentation velocities at the finger and palm

Previous studies suggest that the rate of indentation of a tactile probe determines which skin mechanoreceptors are activated. To further investigate this possibility, indentations of 300 microm at velocities of 100 (T100) and 400 microm/ms (T400) were applied to the tip (FT) and the proximal phalanx of digit III (PP) and the thenar eminence (Pm) of ten healthy volunteers, and compared with responses after electrical stimulation at the FT. Compound sensory action potentials (CSAPs) were recorded from the median nerve through needle electrodes at the wrist and elbow. The maximal sensory conduction velocities (SNCVs) between wrist and elbow were similar with electrical and T400 stimulation, but on average were 15% lower with T100 stimulation (P < 0.001). With both indentation velocities, SNCVs were similar regardless of stimulation sites. Amplitudes of tactile CSAPs with FT stimulation were 1--2 microV at T400 and 0.3--0.4 microV at T100. The CSAP areas evoked by T100 stimulation showed a reduction from fingertip to proximal finger to palm (P < 0.05-0.005), whereas those obtained with T400 stimulation showed a reduction only at the palm (P < 0.05). The results support previous studies indicating that fast indentation at 400 microm/ms activated deeply placed Pacinian corpuscles as well as superficially situated Meissner corpuscles, whereas slower indentation at 100 microm/ms activated primarily Meissner corpuscles.

Sudden death due to cardiovascular disorders: a review of the studies on the medico-legal cases in Tokyo

The Tokyo Metropolitan Government has a medical examiner system, in which all cadavers classified as "unusual death" in the city of Tokyo should be examined, and if necessary, autopsied to determine the cause of death. Of about 10,000 unusual deaths examined per year, two thirds are usually determined to have died of natural causes. The most common cause of sudden natural death is ischemic heart disease, especially acute myocardial infarction. Pathological examination, however, proves acute myocardial ischemia in only one third of autopsies. Subarachnoid hemorrhage and intracerebral hemorrhage, acute myocarditis and cardiomyopathies and aortic dissection/aneurysm as well as pulmonary thromboembolism are frequent causes of death in medical examiner cases. Both pathological and socio-medical problems associated with these diseases are discussed.

Adjuvant chemotherapy for large cell carcinoma with neuroendocrine features

BACKGROUND

In 1999, the World Health Organization categorized large cell neuroendocrine carcinoma, large cell carcinoma with neuroendocrine differentiation, and large cell carcinoma with neuroendocrine morphology as a variant of large cell carcinoma. Patients with large cell carcinoma with neuroendocrine features have poor prognoses, comparable to those for small cell lung carcinoma. Small cell lung carcinoma is sensitive to chemotherapy; however, it is still unclear whether large cell carcinoma with neuroendocrine features is responsive to adjuvant chemotherapy.

METHODS

The authors analyzed 73 patients with large cell carcinoma with neuroendocrine features who underwent resection of the tumor and studied the effect of adjuvant chemotherapy for large cell carcinoma with neuroendocrine features.

RESULTS

In patients with Stage I disease, the overall survival for patients with adjuvant chemotherapy based on cisplatin, carboplatin, or cyclophosphamide, which were used as standard chemotherapy for small cell lung carcinoma, were significantly higher than the overall survival for patients without adjuvant chemotherapy. In patients with Stage II, III, and IV disease, there was no significant difference between patients with adjuvant chemotherapy and without adjuvant chemotherapy.

CONCLUSIONS

Adjuvant chemotherapy based on cisplatin, carboplatin, or cyclophosphamide prolongs survival of patients with large cell carcinoma with neuroendocrine features in early stage.

Coexistence of five Cercopithifilaria species in the Japanese rupicaprine bovid, Capricornis crispus

The Japanese serow, Capricornis crispus (Bovidae, Caprinae, Rupicaprini), is parasitized by five Cercopithifilaria species: C. shohoi, recently described, and reexamined in this paper, C. multicauda n. sp., C. minuta n. sp., C. tumidicervicata n. sp., and C. bulboidea n. sp. Coinfections are frequent. The location (skin or subcutaneous regions) in the host of adult worms differed between the species, as did many morphological characters of both adults and microfilariae. The location (limbs, trunk, etc.) in the host of adult worms and dermal microfilariae seemed to differ depending on the species. Male and female worms of the same species had similar head shapes, buccal capsules, and, in four species, swellings in the anterior region of the body (because of the presence of a giant ventral pseudocoelomocyte). The Cercopithifilaria spp. from C. crispus were related to the primitive forms of the genus, parasites of Bovidae and Cervidae, presently recorded in Africa and Europe. C. bulboidea was particularly close to the most primitive species, C. ruandae and C. dermicola, in Africa, with the pairs of caudal papillae numbered 8 and 9 being distant from each other, but the species also had several specialized characters. Like C. rugosicauda in a European cervid, the four other species had pairs 8 and 9 close to each other; they reflect an evolutionary trend (hypertrophy of pair 6, and reduction and posterior migration of pair 7) that suggests diversification in the host.

Increased telomerase activity and elevated hTERT mRNA expression during multistage carcinogenesis of squamous cell carcinoma of the lung

BACKGROUND

Telomerase activation is believed to play a critical role in the immortalization of cells and carcinogenesis. Telomerase activity is undetectable in normal somatic cells (except for those cells undergoing proliferation) but is expressed in the majority of human tumors including lung carcinoma. The expression of hTERT mRNA has been found to be correlated with telomerase activity. In the current study, the authors analyzed telomerase activity and hTERT mRNA expression in preinvasive bronchial lesions using biopsy specimens obtained by fluorescence bronchoscopy.

METHODS

The authors studied 150 bronchial biopsy specimens obtained by fluorescence bronchoscopy. The intensity of telomerase activity was determined by the fluorescence-based telomeric repeat amplification protocol method in 74 bronchial biopsy specimens (22 normal bronchial epithelium or bronchitis cases, 15 squamous metaplasia cases, 23 dysplasia cases, and 14 squamous cell carcinoma cases), and the level of hTERT mRNA was analyzed in another 76 specimens (24 normal bronchial epithelium or bronchitis cases, 15 squamous metaplasia cases, 20 dysplasia cases, and 17 squamous cell carcinoma cases) by real-time polymerase chain reaction.

RESULTS

The mean values (+/- the standard deviation [SD]) of telomerase activity in normal bronchial epithelium or bronchitis, squamous metaplasia, dysplasia, and squamous cell carcinoma cases were 6.2 +/- 7.5, 13.9 +/- 14.8, 18.5 +/- 20.8, and 54.5 +/- 22.3 U/microg protein, respectively. The upper limit of telomerase activity in normal bronchial epithelium or bronchitis was 21 U/microg protein (mean + 2SD). It is interesting to note that, 5 of 15 squamous metaplasia biopsies (33%), 8 of 23 dysplasia biopsies (35%), and all squamous cell carcinoma biopsies (100%) exhibited levels of telomerase activity that were > 21 U/microg protein. The mean levels of hTERT mRNA in normal bronchial epithelium or bronchitis, squamous metaplasia, dysplasia, and squamous cell carcinoma cases were 891 +/- 840, 1936 +/- 1704, 3019 +/- 2607, and 12965 +/- 18008 copies/microg total RNA, respectively. Telomerase activity and hTERT mRNA expression were found to increase in proportion to the severity of histologic change from normal bronchial epithelium or bronchitis to squamous cell carcinoma.

CONCLUSIONS

These results suggest that an increase in telomerase activity and hTERT mRNA expression are features of the early stages of the development of squamous cell carcinoma of the lung, with strong telomerase activity and hTERT mRNA expression being prominent during the latter stages.

Urokinase receptor and vascular endothelial growth factor are synergistically associated with the liver metastasis of colorectal cancer

Considering recent findings that the urokinase plasniinogen activation (PA) system is involved in invasion and vascular endothelial growth factor (VEGF) is involved in angiogenesis of colorectal cancer, we evaluated these factors in the liver metastasis of primary colorectal cancer. Cancer tissues from 71 colorectal cancer patients were assayed quantitatively for antigen levels of urokinase type plasminogen activator (uPA), uPA receptor (uPAR), and plasminogen activator inhibitor‐1 and ‐2 (PAI‐1, PAI‐2), and were also assayed immunohistochemically for expression of VEGF protein. Among the PA system factors, both the levels of uPAR and PAI‐1 were significantly higher in larger tumors than in smaller ones, and were also significantly higher in tumors that invaded subserosa, serosa or adjacent organs than in mucosal, submucosal tumors or in tumors that invaded the muscle layer. The uPAR levels were significantly higher in tumors with liver metastasis than in those without. VEGF overexpression was significantly more frequent in tumors with lymph node involvement or liver metastasis than in those without. Among the PA system factors, the uPAR levels were significantly higher in tumors with VEGF overexpression and a multivariate analysis revealed that high uPA level and VEGF overexpression were independent risk factors for liver metastasis. The combination of high uPAR level and overexpression of VEGF was associated with the worst prognosis in patients with colorectal cancer. These results suggest that uPAR and VEGF might contribute Synergistically to the liver metastasis of colorectal cancer.

Transfer of bcl-xs plasmid is effective in preventing and inhibiting rat hepatocellular carcinoma induced by N-nitrosomorpholine

To examine the effect of the bcl-xs gene on the sequence from hepatic precancerous lesions, foci and neoplastic nodules, to hepatocellular carcinomas, Sprague-Dawley rats were given water containing 175 mg/l N-nitrosomorpholine (NNM) for 8 weeks. At weeks 1, 4 and 7, the left lobe of the rat liver was exposed and injected with the bcl-xs plasmid (pCR3.1-rat bcl-xs cDNA) or pCR3.1 encapsulated in cationic empty liposomes each at a dose of 80 microg plasmid/kg body weight. One minute later, low-field-strength, long-duration electric pulses were applied to the left lobe using a pincette electrode with circular poles 1 cm in diameter. The in vivo electroporation procedure significantly increased the transfer of the reporter gene chloramphenicol acetyl transferase (CAT) plasmid via empty liposomes. Thus, CAT mRNA was expressed not only at the sites of electrode contact but at sites 0.5-1.0 cm away from the electrode, and expression also increased with increasing doses of plasmid, meaning that in vivo electroporation enabled the expression of plasmid DNA throughout an extensive area of the rat liver. By week 11, the neoplastic nodules were significantly fewer and smaller in the bcl-xs group than in the pCR3.1 group at the two sites, one with and the other without electrode contact. No hepatocellular carcinomas were found in the rats that had received the bcl-xs plasmid, whereas these tumors were observed in 30% of the rats given pCR3.1. Moreover, overexpression of the bcl-xs protein was detected, and apoptotic activity was significantly increased in the neoplastic nodules, foci and hepatocytes adjacent to the hepatic lesions. These results indicate that the bcl-xs plasmid inhibits the occurrence and growth of rat hepatocellular carcinoma and may thus be effective for the prevention and treatment of human liver tumors.

Epstein-Barr virus involvement is mainly restricted to lymphoepithelial type of gastric carcinoma among various epithelial neoplasms

To demonstrate the association of Epstein-Barr virus (EBV) with primary epithelial neoplasms in the south part of Kyushu, Japan, 761 carcinomas consisting of 75 lung, 61 breast, 107 esophagus, 102 colon, 58 pancreas, 45 thyroid, and 313 gastric cancers were examined by EBER-1 in situ hybridization. EBER-1 was detected in 23 cases (7.3%) out of 313 gastric carcinomas, while none of the other carcinomas was positive for EBER-1. Twenty-eight (9.4%) out of 313 gastric carcinomas were differentiated poorly to moderately carcinomas with prominent lymphoid cell infiltration, similar to so-called lymphoepithelioma-like carcinoma, and 19 cases (67.9%) were positive for EBER-1. Although two (2.6%) and 11(10.3%) out of 75 lung and 107 esophagus carcinomas were so-called lymphoepithelioma-like carcinomas, respectively, but EBER-1 was not detected in other epithelial neoplasms that originated from the lung, esophagus, breast, colon, pancreas, and thyroid in the south of Kyushu, Japan. As a result, EBV was associated with only some gastric carcinomas but not with other epithelial neoplasms originating from the lung, esophagus, breast, colon, pancreas, and thyroid in southern Japan.

Clinical significance and prognostic value of apoptosis related proteins in superficial esophageal squamous cell carcinoma

BACKGROUND

The purpose of the present study was to examine the expression of cell cycle regulators [p53, p21WAF1/CIP1 (p21), and Rb] and apoptosis related proteins Bax and Bcl-X(L) and to evaluate the relationship between their expressions and clinicopathological findings in patients with superficial squamous cell carcinomas of the esophagus.

METHODS

We immunohistochemically investigated the expression of p53, p21, Rb, Bax, and Bcl-X(L) in 79 patients with superficial esophageal carcinoma.

RESULTS

p21 overexpression was found in mucosal carcinoma (P = 0.05) and a high Bcl-X(L) score was observed for submucosal carcinoma (P = 0.03). The patients with high Bcl-X(L) score had more frequent lymphatic invasion and lymph node metastasis than did those with low Bcl-X(L) score (P < 0.05). Univariate analysis revealed significantly shorter survival in patients with high Bcl-X(L) expression than in those with low Bcl-X(L) expression, but Bcl-X(L) expression was not identified as an independent prognostic factor by multivariate analysis.

CONCLUSIONS

Because Bcl-X(L) expression correlated well with depth of tumor invasion, lymphatic invasion, and lymph node metastasis, examination of Bcl-X(L) expression will help to estimate the properties in superficial squamous cell carcinoma of the esophagus.

Inhibition by d-limonene of experimental hepatocarcinogenesis in Sprague-Dawley rats does not involve p21(ras) plasma membrane association

The effects of d-limonene on hepatocarcinogenesis induced by N-nitrosomorpholine (NNM) and on membrane-associated p21(ras) and labeling and apoptotic indices of the liver were investigated in male Sprague-Dawley rats. Rats were given drinking water containing NNM for 8 weeks, and from the beginning of experimental week 9, they received chow pellets containing 1% or 2% limonene. The preneoplastic and neoplastic liver lesions (cellular alteration foci, neoplastic nodules and hepatocellular carcinomas), and hepatic foci staining positive for glutathione-S-transferase, placental type (GST-P) were examined microscopically and histochemically. At week 16, quantitative histologic analysis showed that oral administration of 1% or 2% limonene resulted in significant reductions in the number and mean area of GST-P-positive hepatic foci and the number of cellular alteration foci, neoplastic nodules and hepatocellular carcinomas. Limonene, at both doses, also caused significant decreases in the labeling indices and significant increases in the apoptotic indices of cellular alteration foci, neoplastic nodules, hepatocellular carcinomas and adjacent liver. However, limonene, at both doses, had no significant influence on the production of membrane-associated p21(ras) in the visible liver white nodules. These findings indicate that limonene inhibits hepatocarcinogenesis and suggest that this effect may be clearly related to its effect in inhibiting cell proliferation and in enhancing apoptosis, but not through ras oncoprotein plasma membrane association.

Attenuation by ambroxol of monochloramine-enhanced gastric carcinogenesis: a possible prevention against Helicobacter pylori-associated gastric carcinogenesis

The effects of combined administration of a reactive oxidant, monochloramine, and a mucoregulatory agent, ambroxol, on the development of gastric cancers induced by N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) were investigated in inbred Wistar rats. After receiving oral MNNG and regular chow pellets for 25 weeks, rats received regular chow pellets or chow pellets containing 20% ammonium acetate, and normal tap water or water containing 30 mM sodium hypochlorite, with or without subcutaneous injection of ambroxol at high or low doses, until the end of the experiment at week 52. Treatment with both ammonium acetate and sodium hypochlorite, which produce monochloramine, significantly increased the incidence of gastric cancers at week 52, whereas concomitant administration of ambroxol with ammonium acetate and sodium hypochlorite significantly attenuated this enhanced gastric carcinogenesis. Results also revealed that ambroxol scavenged monochloramine. Because monochloramine is closely related to Helicobacter pylori-associated gastric carcinogenesis, these findings suggest that ambroxol may prevent H. pylori-associated gastric carcinogenesis.

Colonization with Schizophyllum commune of localized honeycomb lung with mucus

We report a surgical case involving localized honeycomb lung with mucus, caused by colonization of a Schizophyllum commune, which displayed a tumorous shadow in the right upper mediastinum. A 74-year-old male with a history of tuberculosis in the 1970s was referred to Chiba University Hospital (Chiba, Japan) with an abnormal shadow evident in the chest roentgenogram. A transbronchial biopsy failed to yield a definite diagnosis. We resected the right upper lobe, which was found to contain a consolidative lesion filled with viscous mucus in the right upper lobe adjacent to the right upper mediastinum. Microscopic examination revealed a honeycomb lung formation with mucus in the destroyed space. Culture of the mucus yielded a whitish filamentous fungus, positively identified as S. commune. This is the first report of S. commune leading to a deposit of mucus and the formation of a consolidative lesion in the destroyed lung.

Electrophysiological changes in diabetic neuropathy: from subclinical alterations to disabling abnormalities

Clinical spectrum of diabetic neuropathy is variable; it may be asymptomatic, but once established as polyneuropathy, it is irreversible and may finally be disabling. To estimate the prevalence of subclinical diabetic polyneuropathy in the UAE, we undertook a pilot study by means of nerve conduction study (NCS) of peroneal motor and sural sensory studies in 60 diabetics with no symptoms of neuropathy. Neurological examination revealed clinical abnormalities suggesting polyneuropathy in 26 patients, 43% of the patients. NCS revealed abnormal values in 63% of the whole patients. Abnormal NCS was confirmed in 88% of the positive sign group. As to the negative sign group 44% had abnormalities in NCS. Prolonged F-wave latency was seen in 29% in no sign group and in 66% of the patients with positive signs. We found close association between neurological deficit score and abnormalities in NCS. Among various parameter of systemic nerve conduction study in subclinical patients, prolonged F-wave latency seems the commonest abnormality suggesting morphological changes in subclinical diabetic nerve. Decrease in amplitude of compound sensory action potential of sural nerve is another earlier abnormality, which is, then, accompanied by a fall in motor amplitude of peroneal nerve in advanced patients. Recently, our own group of Hirosaki has demonstrated that somatosensory central conduction time (CCT) between the spinal cord entry time and the arrival time to the sensory cortex is prolonged in diabetics. This abnormality might be partly responsible for the irreversible sensory deficits of diabetic neuropathy.

Microsatellite alterations in patients with thoracic sarcoma

Few studies on sarcomas have examined the relationships between microsatellite alterations in particular loci, tumor prognosis and tumorigenesis, because sarcomas are uncommon and those prognoses can be confounded by coexisting factors, such as tumor site. We studied the relationship between microsatellite alterations and prognosis in 31 patients with thoracic sarcoma. The frequency of loss of heterozygosity (LOH) at 17p13 in stage IV sarcomas was significantly higher than that in stage I and III sarcomas (p<0.05). The 5-year survival for patients with LOH at 17p13 was significantly lower than that for patients without LOH (p<0.05). Six of 31 cases (19.4%) revealed replication error. These results suggest that p53 abnormality occurs during advanced stages of sarcoma and are related to patient prognosis, and it is possible that aberrations in mismatch repair activity are related to sarcoma tumorigenesis.

Relationship of p53 and Helicobacter pylori to clinicopathological features of human remnant stomach cancer after gastric surgery for primary gastric cancer

The purpose of this study was to evaluate the biological features of gastric cancer of the remnant stomach (RSC). Twenty-one patients underwent resection of the remnant stomach for RSC and were divided into two groups: the RSCB group consisted of 11 patients who underwent distal gastrectomy for benign disease and the RSCM group consisted of 10 patients who underwent gastrectomy for primary gastric cancer. The interval between primary surgery and the appearance of gastric cancer in the remnant stomach was significantly shorter in the RSCM group than in the RSCB group. Invasion of adjacent organs was more frequent in the RSCM group than in the RSCB group and the Ki-67 labeling index of the tumors was significantly higher in the former group. Furthermore, p53 overexpression by tumors was almost twice as common in the RSCM group as in the RSCB group. Although there was no significant difference of the H. pylori positivity between the two groups, the rate for both groups was higher than reported in previous studies. Mutation of p53 may play an important role in the high proliferative activity of tumors in the RSCM group and H. pylori infection may be closely related to carcinogenesis in patients with RSC.

A case of breast cancer diagnosed by inguinal lymph node metastasis

We describe a case of a 58-year-old woman with right inguinal lymph node swelling and a T1 tumor in the right breast. She was referred with an 18-month history of the former complaint and a six-month history of the latter. Excisional biopsy of the inguinal lymph node revealed breast cancer metastasis. Radiographical examination showed no metastases to the lungs, liver or bone. Modified radical mastectomy was performed. Histological examination revealed solid tubular carcinoma, PT2, PM (axillary lymph node metastases 4/16), stage IV. Estrogen and progesterone receptors were negative. Three cycles of postoperative cyclophosphamide, adriamycin and 5-fluorouracil (CAF) chemotherapy were given, and the right inguinal area was irradiated with 40 Gy. The patient complained of swelling in both legs three years after surgery. Computed tomography revealed marked lymph node swellings in the pelvic cavity. She died six months later. Inguinal lymph node metastasis from breast cancer is very rare, although distant lymph node metastasis in the cervix occurs frequently. This case should help clarify how breast cancer metastasizes to distant lymph nodes.

Effect of combination therapy with matrix metalloproteinase inhibitor MMI-166 and mitomycin C on the growth and liver metastasis of human colon cancer

Several synthetic inhibitors of matrix metalloproteinases (MMPs) show antitumor, antimetastasis and antiangiogenesis effects in various models. Synergistic effects of combinations with conventional cytotoxic agents were reported previously. In this study, we examined the effects of a new selective MMP inhibitor, MMI-166, on tumor growth, angiogenesis and metastasis in a liver metastatic model of human xenotransplanted colon cancer (TK-4). We also investigated the synergistic effects of MMI-166 and a conventional cytotoxic agent, mitomycin C (MMC), in this model. Mice transplanted orthotopically with TK-4 were divided into 4 groups; a control group (treated with vehicle solution), an MMI-166 group in which MMI-166 was orally administered (p.o.) at a dose of 200 mg / kg, 6 days / week for 5 weeks, an MMC group in which MMC was administered intraperitoneally (i.p.) at a dose of 2 mg / kg / week for 5 weeks, and a combination group (treated with MMI-166 and MMC). MMI-166 did not inhibit transplanted tumor growth, but significantly inhibited liver metastasis compared with the control group and MMC group (P < 0.01). Significant antitumor and antimetastatic effects of the combination therapy were demonstrated. The microvessel density (MVD) detected by immunohistochemical staining with ER-MP12 antibody tended to be lower in the MMI-166 and the combination groups. These results suggest that MMI-166 has potential antimetastatic ability and a synergistic effect with MMC.

Detection and prediction of micrometastasis in the lymph nodes of patients with pN0 gastric cancer

BACKGROUND

The clinicopathologic significance of micrometastasis (MM) and tumor cell microinvolvement (TCM) in regional lymph nodes as identified by immunohistochemical staining for cytokeratin expression was evaluated in patients with node-negative gastric cancer.

METHODS

MM was defined as tumor cells with stromal reaction, and TCM was defined as individual tumor cells without stromal reaction. We investigated 1761 lymph nodes obtained from 67 gastric cancer patients whose diagnosis showed no lymph node metastasis by routine histological examination. The depth of tumor invasion was T1 (submucosa) in 33 patients and T2 (muscularis propria and subserosa) in 34 patients. The lymph nodes were examined immunohistochemically for the presence of tumor cells using anti-cytokeratin AE1/AE3 monoclonal antibody. Both the biopsy tumor specimens obtained prior to surgery and the resected primary tumors were immunostained with E-cadherin (E-cad) monoclonal antibody.

RESULTS

Thirty (1.5%) of the 1761 lymph nodes showed MM and/or TCM. MM with or without TCM was found in 10 patients, and TCM alone was found in 4 patients; 6 (18.2%) of the 33 patients with T1 tumor and 8 (23.5%) of the 34 patients with T2 tumor had occult lymph node metastasis. The 5-year survival rate was worse among those with MM with or without TCM, than among those without MM. Nearly all of the patients with MM and/or TCM had reduced or negative E-cad expression in the primary tumor.

CONCLUSIONS

We demonstrated that the incidence of MM and/or TCM in the lymph nodes of patients with gastric cancer is quite high, and that such metastasis is associated with the prognosis of patients with pN0. Examination of E-cad expression in biopsy tumor specimens may be useful for predicting MM and/or TCM.

Tumor suppressor protein VHL is induced at high cell density and mediates contact inhibition of cell growth

In spite of the general recognition of von Hippel-Lindau (VHL) as a tumor suppressor gene, the physiological and pathological importance of VHL protein in cell growth regulation and tumorigenesis remains unclear. Here we show that in normal human renal proximal tubule epithelial cells (RPTEC), the steady-state amount of VHL protein is strictly regulated by cell density. The cellular VHL content is more than 100-fold higher in dense cultures than in sparse cultures. The increase in VHL protein at high cell density was also observed for NIH3T3 fibroblasts, suggesting the generality of the phenomenon. The growth rates of renal cell carcinoma cells lacking an intact VHL gene and their derivatives with wild-type or mutant VHL expression vector do not differ significantly when they are growing in log-phase. Importantly, however, there is a difference when they reach confluency: cells lacking wild-type VHL grew continuously, while cells expressing exogenous VHL protein showed relatively limited cell growth. Using an ecdysone-inducible VHL expressing cell line, we also show that the growth inhibition at high cell density can be released by attenuating the VHL expression. Taken together, we propose that VHL protein functions as a growth suppressor at high cell density, and this might be the basis of the tumor suppressor function of VHL.

Three-drug combinations of emivirine and nucleoside reverse transcriptase inhibitors in vitro: long-term culture of HIV-1-infected cells and breakthrough viruses

Emivirine (EMV) is a non-nucleoside reverse transcriptase inhibitor currently undergoing Phase III clinical trials in HIV-1-infected patients. In this study, the anti-HIV-1 activity of EMV in combination with two nucleoside reverse transcriptase inhibitors was examined in cell cultures. The combinations EMV plus stavudine (d4T) plus lamivudine (3TC) and EMV plus d4T plus didanosine (ddI) synergistically inhibited HIV-1 replication in MT-4 cells. Although not statistically significant, EMV plus d4T plus 3TC appeared to be more synergistic than EMV plus d4T plus ddI. Synergism was also observed with any two-drug combinations, such as EMV plus d4T, EMV plus 3TC, EMV plus ddI, d4T plus 3TC, or d4T plus ddI. The three-drug combinations completely suppressed HIV-1 replication for at least 40 days after virus infection. Except for d4T, virus emerged in the presence of every compound alone or some combinations at lower concentrations. Susceptibility tests of the breakthrough viruses to each compound showed that the viruses obtained in the presence of EMV alone and 3TC alone were significantly less susceptible to EMV and 3TC, respectively. These viruses had specific amino acid mutations in their reverse transcriptase.

Alveolar Macrophages that Phagocytose Apoptotic Neutrophils Produce Hepatocyte Growth Factor during Bacterial Pneumonia in Mice

Hepatocyte growth factor (HGF) is postulated to play an important role in the repair of pulmonary epithelium in acute lung injury. To evaluate the role of HGF in bacterial pneumonia, the kinetics of HGF production and the cellular sources of HGF have been examined in the lungs of mice that had been intratracheally challenged with Pseudomonas aeruginosa. Neutrophil accumulation in the airway occurred immediately, reached a peak at 36 h, and then progressively declined by 14 d after infection. We found a biphasic pattern of HGF messenger RNA expression and protein synthesis in the lung after bacterial infection. The first peak for HGF production was found at 6 h after infection, and the primary source of HGF was shown to be bronchial epithelial cells. Interestingly, the second peak for HGF production, which was found around 48 to 72 h after infection, was closely associated with the increase in the percentage of alveolar macrophages (AMs) that became positive for myeloperoxidase, indicating phagocytosis of apoptotic neutrophils. The cellular source of the second peak was found to be AMs. Further, murine AMs which phagocytosed apoptotic neutrophils induced higher levels of HGF production in vitro. These results strongly indicate a novel mechanism of HGF production by AMs, which are phagocytosing apoptotic neutrophils, and the pivotal role of AMs in the healing and repair of damaged pulmonary epithelium through the production of HGF.

Expression of vascular endothelial growth factor in thoracic sarcomas

BACKGROUND

A body of data indicates that vascular endothelial growth factor (VEGF) expression by carcinomas is closely related to the prognosis of carcinomas. However, the relationship between VEGF expression and the prognosis of sarcomas is contradictory.

METHODS

Tissue from 27 cases of thoracic sarcoma was analyzed immunohistochemically for VEGF expression while tumor vascularity was quantified using an antibody directed against endothelial CD34. The relationship between VEGF expression and the prognosis of patients with sarcomas was then evaluated semiquantitatively.

RESULTS

The microvessel count in sarcomas with strong VEGF expression was significantly higher than that in sarcomas with absent or faint VEGF expression. The disease-free survival rates of sarcomas with strong VEGF expression were significantly lower than those of sarcomas with absent or faint VEGF expression. We found that strong VEGF expression impacted on the disease-free survival in multivariate analyses.

CONCLUSIONS

VEGF expression of thoracic sarcomas is directly related to angiogenesis and tumor vascularity, and our findings suggest that strong VEGF expression is an independent prognostic factor in patients with thoracic sarcomas.

[Effective combination chemotherapy for a recurrent case of carcinoma of the remnant stomach]

A 69-year-old-man underwent distal gastrectomy for gastric carcinoma in 1988. Another gastric carcinoma was discovered in the remnant stomach in March 1995. Total gastrectomy and lymph node dissection were performed. CEA was up and we detected a big left suprarenal mass by abdominal CT. Suprarenalectomy was performed in June 1997. The swelling of lymph nodes was detected by CT and CEA was up to 1,000. Combination chemotherapy with intermittent 5-fluorouracil (5-FU) and low-dose cisplatin (CDDP) was performed. CEA suddenly decreased and lymph node swelling was reduced.

Fluorescence bronchoscopy in the detection of preinvasive bronchial lesions in patients with sputum cytology suspicious or positive for malignancy

BACKGROUND

A new strategy in the treatment of squamous cell carcinoma of the tracheobronchial tree is the detection and eradication of preinvasive bronchial lesions before they become invasive cancers. It is, however, difficult to detect preinvasive lesions by conventional white-light bronchoscopy alone.

PURPOSE

we conducted a detailed investigation on the use of fluorescence bronchoscopy in the detection of preinvasive bronchial lesions in patients with sputum cytology suspicious or positive for malignancy.

METHODS

64 participants with sputum cytology suspicious or positive for malignancy were examined with both white light and fluorescence bronchoscopy (LIFE group). Earlier to this study, before fluorescence bronchoscopy became available in our institute, 48 participants having sputum cytology suspicious or positive for malignancy were examined with white light bronchoscopy alone (control group). Biopsy specimens for pathological examinations were taken of all abnormal areas discovered by white light or fluorescence bronchoscopy examination.

RESULTS

In sputum cytology suspicious or positive for malignancy, the diagnosis of preinvasive bronchial lesions was greatly enhanced in the LIFE group as compared with the control group (45 vs. 7 lesions). The percentage of participants with preinvasive bronchial lesions was also significantly higher in the LIFE group than in the control group (40.6 vs. 12.5%, P = 0.00087, respectively).

CONCLUSIONS

Our study suggests that the use of fluorescence bronchoscopy in addition to conventional white-light examination could greatly enhance the detection and localization of preinvasive bronchial lesions in patients with sputum cytology suspicious or positive for malignancy.

Inactivation of SSI-1, a JAK/STAT inhibitor, in human hepatocellular carcinomas, as revealed by two-dimensional electrophoresis

BACKGROUND/AIMS

Hepatocellular carcinoma (HCC) is one of the most common human cancers, and many efforts have been paid to discover aberrant expression control in HCC, however the specific molecular mechanisms involved in hepatocarcinogenesis remain to be determined.

METHODS

To investigate genomic changes that occur in human primary hepatocellular carcinomas (HCC), we carried out restriction landmark genomic scanning. This two-dimensional electrophoretic system displays 2000-3000 NotI-landmark sites in a single gel.

RESULTS

We detected one landmark spot that showed diminished signal intensities in a majority of the HCCs we examined. Cloning revealed that this spot represented a NotI-cluster sequence that was enriched with CpG dinucleotides in the promoter region of a gene encoding Janus kinase (JAK)-binding protein, SSI-1 (also known as JAB1 or SOCS-1). Expression of the SSI-1 gene was markedly reduced in half of eight HCCs analyzed.

CONCLUSIONS

This protein regulates the Janus kinase signal transducers and activators of transcription signal transduction pathway, which transmits signals from cytokines to the intracellular apparatus. These data suggest that dysregulation of the pathway relate with progression of HCC.

Detection and prediction of micrometastasis in the lymph nodes of patients with pN0 gastric cancer

BACKGROUND

The clinicopathologic significance of micrometastasis (MM) and tumor cell microinvolvement (TCM) in regional lymph nodes as identified by immunohistochemical staining for cytokeratin expression was evaluated in patients with node-negative gastric cancer.

METHODS

MM was defined as tumor cells with stromal reaction, and TCM was defined as individual tumor cells without stromal reaction. We investigated 1761 lymph nodes obtained from 67 gastric cancer patients whose diagnosis showed no lymph node metastasis by routine histological examination. The depth of tumor invasion was T1 (submucosa) in 33 patients and T2 (muscularis propria and subserosa) in 34 patients. The lymph nodes were examined immunohistochemically for the presence of tumor cells using anti-cytokeratin AE1/AE3 monoclonal antibody. Both the biopsy tumor specimens obtained prior to surgery and the resected primary tumors were immunostained with E-cadherin (E-cad) monoclonal antibody.

RESULTS

Thirty (1.5%) of the 1761 lymph nodes showed MM and/or TCM. MM with or without TCM was found in 10 patients, and TCM alone was found in 4 patients; 6 (18.2%) of the 33 patients with T1 tumor and 8 (23.5%) of the 34 patients with T2 tumor had occult lymph node metastasis. The 5-year survival rate was worse among those with MM with or without TCM, than among those without MM. Nearly all of the patients with MM and/or TCM had reduced or negative E-cad expression in the primary tumor.

CONCLUSIONS

We demonstrated that the incidence of MM and/or TCM in the lymph nodes of patients with gastric cancer is quite high, and that such metastasis is associated with the prognosis of patients with pN0. Examination of E-cad expression in biopsy tumor specimens may be useful for predicting MM and/or TCM.

A Role of RNA Helicase A in cis-Acting Transactivation Response Element-mediated Transcriptional Regulation of Human Immunodeficiency Virus Type 1

RNA helicase A (RHA) has two double-stranded (ds) RNA-binding domains (dsRBD1 and dsRBD2). These domains are conserved with the cis-acting transactivation response element (TAR)-binding protein (TRBP) and dsRNA-activated protein kinase (PKR). TRBP and PKR are involved in the regulation of HIV-1 gene expression through their binding to TAR RNA. This study shows that RHA also plays an important role in TAR-mediated HIV-1 gene expression. Wild-type RHA preferably bound to TAR RNA in vitro and in vivo. Overexpression of wild type RHA strongly enhanced viral mRNA synthesis and virion production as well as HIV-1 long terminal repeat-directed reporter (luciferase) gene expression. Substitution of lysine for glutamate at residue 236 in dsRBD2 (RHA(K236E)) reduced its affinity for TAR RNA and impaired HIV-1 transcriptional activity. These results indicate that TAR RNA is a preferred target of RHA dsRBDs and that RHA enhances HIV-1 transcription in vivo in part through the TAR-binding of RHA.

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.

PTEN/MMAC1/TEP1 mutations in human primary renal-cell carcinomas and renal carcinoma cell lines

Extensive allelotyping studies have implicated several tumor-suppressor loci on chromosomes 3p, 5q, 6q, 8p, 9pq, 10q, 11q, 14q, 17p, 18q and 19p in human kidney tumorigenesis. The PTEN (also called MMAC1 and TEP1) gene, a candidate tumor suppressor located at chromosome 10q23.3, is mutated in a variety of sporadic malignancies as well as in patients with Cowden disease. To investigate the potential role of the PTEN gene in renal tumorigenesis, we searched for abnormalities of the gene in 68 primary renal-cell carcinomas (RCCs) as well as in 17 renal carcinoma-derived cell lines, using DNA-SSCP, sequencing and microsatellite analysis. Five of 68 (7.5%) primary RCCs exhibited intragenic mutations (3 missense, 1 deletion and 1 splice-site), and 1 of 17 (5.9%) cell lines had an insertion mutation. Loss of heterozygosity of the PTEN gene occurred in 25% of primary RCCs, including the 3 cases with intragenic mutation and the 1 PTEN-mutated cell line. Clinical and histopathological examinations revealed that 4 of the 5 primary tumors with PTEN mutation were high-grade, advanced clear-cell RCCs with distant metastases or renal vein tumor invasions, resulting in poor prognostic courses. The other was a low-stage papillary/chromophilic RCC. Our data suggest that PTEN mutation is observed in a subset of RCCs and that, especially in clear-cell RCCs, it occurs as a late-stage event and may contribute to the invasive and/or metastatic tumor phenotype.

Preserved Smad4 expression in the transforming growth factor beta signaling pathway is a favorable prognostic factor in patients with advanced gastric cancer

The signals of the transforming growth factor beta (TGF-beta) superfamily are conveyed through cell surface serine/threonine kinase receptors to the intracellular mediators known as Smads. Activation of Smads causes their translocation from the cytoplasm to the nucleus, where they function to control gene expression. The present study analyzed the expression of Smad4 and TGF-beta1 to determine their prognostic significance in advanced gastric cancer. Of 249 cases of advanced gastric cancer, 41 had invaded the muscular layer, 114 had invaded the subserosal layer, and 94 had invaded the serosa. Anti-Smad4 and TGF-beta1 antibodies were used for immunohistochemical staining. Reduced expression of Smad4 was 75.1%, whereas positive expression of TGF-beta1 was 39.6% in gastric cancer. Smad4 expression was related to the depth of tumor invasion (P < 0.05), and TGF-beta1 expression correlated with tumor gross type (P < 0.05). Postoperative survival analysis indicated that patients who had a tumor with reduced Smad4 expression had a poorer clinical outcome than those with preserved expression (P < 0.05). Furthermore, in patients with TGF-beta1-positive tumors, survival rate was significantly better in patients with preserved Smad4 expression than in those with reduced Smad4 expression (P < 0.05). According to multivariate analysis, Smad4 expression acted as an independent prognostic factor. Smad4 expression, particularly in the TGF-beta pathway, is an effective predictor of outcome for patients with advanced gastric cancer.

Surgical maneuvers enhance molecular detection of circulating tumor cells during gastric cancer surgery

OBJECTIVE

To evaluate the relation between the presence of cancer cells in blood according to the time course during a surgical procedure and liver metastases in patients with gastric cancer.

SUMMARY BACKGROUND DATA

Several studies have reported on the detection of circulating cancer cells in blood by reverse transcriptase-polymerase chain reaction (RT-PCR). However, few reports have examined the relation between molecular detection of circulating cancer cells according to the time course during a surgical procedure and blood-borne metastases.

METHODS

Blood samples from 57 patients with gastric cancer were obtained from the portal vein, peripheral artery, and superior vena cava before and after tumor dissection. After total RNA was extracted from each blood sample, carcinoembryonic antigen (CEA)-specific RT-PCR was performed.

RESULTS

CEA-mRNA was detected in the blood of 21 (36.8%) of the 57 patients. CEA-mRNA was not detected in the blood obtained from 15 healthy volunteers and 15 patients with benign disease. The positive rate increased in proportion to the depth of tumor. The incidence of positive CEA-mRNA did not differ among the various sites of blood sampling. The appearance of circulating cancer cells was related to the surgical maneuver. A significant relation was found between the detection of CEA-mRNA and blood-borne metastases.

CONCLUSIONS

A high incidence of positive CEA-mRNA was found in the blood during gastric cancer surgery. Surgical maneuvers are a possible cause of hematogenous metastasis. The authors found that patients with positive CEA-mRNA had a high risk of blood-borne metastasis even after curative resection.

PTEN/MMAC1/TEP1 mutations in human primary renal-cell carcinomas and renal carcinoma cell lines

Extensive allelotyping studies have implicated several tumor-suppressor loci on chromosomes 3p, 5q, 6q, 8p, 9pq, 10q, 11q, 14q, 17p, 18q and 19p in human kidney tumorigenesis. The PTEN (also called MMAC1 and TEP1) gene, a candidate tumor suppressor located at chromosome 10q23.3, is mutated in a variety of sporadic malignancies as well as in patients with Cowden disease. To investigate the potential role of the PTEN gene in renal tumorigenesis, we searched for abnormalities of the gene in 68 primary renal-cell carcinomas (RCCs) as well as in 17 renal carcinoma-derived cell lines, using DNA-SSCP, sequencing and microsatellite analysis. Five of 68 (7.5%) primary RCCs exhibited intragenic mutations (3 missense, 1 deletion and 1 splice-site), and 1 of 17 (5.9%) cell lines had an insertion mutation. Loss of heterozygosity of the PTEN gene occurred in 25% of primary RCCs, including the 3 cases with intragenic mutation and the 1 PTEN-mutated cell line. Clinical and histopathological examinations revealed that 4 of the 5 primary tumors with PTEN mutation were high-grade, advanced clear-cell RCCs with distant metastases or renal vein tumor invasions, resulting in poor prognostic courses. The other was a low-stage papillary/chromophilic RCC. Our data suggest that PTEN mutation is observed in a subset of RCCs and that, especially in clear-cell RCCs, it occurs as a late-stage event and may contribute to the invasive and/or metastatic tumor phenotype.

[The causes of death in patients with non-MDR pulmonary tuberculosis in our hospital]

We studied the causes of death in 295 patients (mean (+/- SD) age 70.5 +/- 13.2 y.o.) with active non-MDR pulmonary tuberculosis who died in our hospital between 1991 and 1999. A hundred and twenty eight patients (43.4%, group A) died of tuberculosis, while 167 patients (56.6%) of other accompanying diseases. In 46 patients of the latter (15.6%, group B), pulmonary tuberculosis gave an unfavorable impact on their clinical course. In these patients the extent of pulmonary tuberculosis on chest roentgenograph was similar with the remaining 121 patients who also died of the accompanying diseases (41.0%, group C) and was less severe than those of the group A patients. Their nutritional conditions measured by serum albumin and choline-esterase level on admission, however, were as low as those of the group A patients and distinctly worse than those of the group C patients. Most patients of groups A and B died within 3 months after admission, while less than half patients of group C died during the same period. The age frequency distribution of the patients in groups B and C had a single peak in the age group 70 to 89, while that in group A showed two peaks, one similar peak as in groups B and C, and another peak in the age group 50 to 59. The numbers of homeless patients, of the patients with extensive cavitary lesions, and of the patients who died of ARDS (Adult Respiratory Distress Syndrome) or severe pneumothorax in group A were the most also in the age group 50 to 59, indicating that the patients' delay in admitting to hospitals was the major cause of high motality in this age group. As to detailed causes of death in group A, patients died of respiratory failure (32 cases), emaciation (28 cases), progression of pulmonary tuberculosis (20 cases), ARDS (15 cases), tuberculosis-related diseases such as pneumothorax, hemoptysis, and DIC (24 cases). In groups B and C patients died of organ failure (36 cases), infectious diseases (33 cases) and malignancy (30 cases). The total number of died patients has increased, and the proportion of cases dying of ARDS and infectious diseases has increased statistically significantly recently.

[A case of acute sensory neuropathy associated with cytomegalovirus infection]

We report a non-compromised patient with acute sensory neuropathy (ASN) developed following cytomegalovirus (CMV) hepatitis. A 67-year-old man admitted to a hospital because of acute hepatic dysfunction accompanying fever and skin eruption. One month later, when hepatic function normalized, numbness and clumsiness started acutely first in the right upper limb next to all the extremities. He found difficulty in walking in a couple of weeks. One month after the commencement of neurological illness, he was referred to us. On examination, he had sensory limb ataxia. His gait was wide-based, and Romberg sign was positive. Position sense was severely diminished in the extremities. Skin sensation was also attenuated distally, while no motor weakness was noted. Tendon reflexes were almost absent. Nerve conduction studies revealed absent sensory potentials in all but the left median nerve, in which amplitude was 5.5 microV with sensory conduction velocity of 40.7 m/s. Motor conduction studies, on the other hand, appeared normal except for a slight focal delay in the right ulnar nerve across the elbow. Mild increase in F-wave latencies was noted. A sural nerve specimen taken two months after the neurological onset showed a marked decrease in myelinated fiber density and active fiber degenerations accompanying axonal sproutings. Sjögren syndrome and paraneoplastic neuropathy were excluded serologically and by comprehensive imaging techniques. Although IgM anti-CMV antibody was not detected, serum IgG anti-CMV antibody was positive and significantly increased during the neurological illness. The intrathecal antibody synthesis of IgG anti-CMV antibody was suggested by a low serum/cerebrospinal fluid (CSF) antibody ratio and a high CSF IgG index. From these observations, it was strongly suggested that acute hepatitis and subsequent ASN were associated with CMV infection in this patient. Although some cases with post-infectious ASN have been previously reported, this is the first report of ASN preceded by CMV infection.

The role of neoadjuvant radiochemotherapy using low-dose fraction cisplatin and 5-fluorouracil in patients with carcinoma of the esophagus

OBJECTIVE

We clarified the role of neoadjuvant radiochemotherapy in patients with carcinoma of the esophagus and compared it to neoadjuvant chemotherapy.

METHODS

We retrospectively examined 40 patients diagnosed with advanced thoracic esophageal carcinoma who underwent neoadjuvant therapy followed by esophagectomy between 1993 and 1999. We divided them into 2 groups: radiochemotherapy (17) and chemotherapy (23). Radiochemotherapy patients underwent 40 Gy radiation and low-dose fraction cisplatin (7 mg/body/day, 5 days a week x 4 weeks) and 5-fluorouracil (350 mg/body/day x 28 days). Chemotherapy patients received high-dose fraction cisplatin/5-fluorouracil involving 2 courses of cisplatin (70 mg/m2/day on day 1) and 5-fluorouracil (700 mg/m2/day on days 1-5).

RESULTS

Complete pathological response was 17.6% in the radiochemotherapy group and 0% in the chemotherapy group respectively. No hospital mortality occurred in the radiochemotherapy group, and 1 of the 23 chemotherapy patients died in the hospital due to postoperative complications. The incidence of residual tumors was significantly higher in the chemotherapy group (34.8%) than in the radiochemotherapy group (0%). Actuarial survival in the radiochemotherapy group at 1 year was 80.2% and at 3 years 53.5%. Actuarial survival in the chemotherapy group at 1 year was 56.5% and at 3 years 30.4%.

CONCLUSIONS

Histological effectiveness was greater in patients treated with preoperative radiochemotherapy than those treated with preoperative chemotherapy. The combination of radiation and low-dose fraction CDDP/5-FU thus is first choice in neoadjuvant radiochemotherapy for the advanced esophageal carcinoma.

Suppression by verapamil of bombesin-enhanced peritoneal metastasis of intestinal adenocarcinomas induced by azoxymethane in wistar rats

BACKGROUND

The effects of combined administration of bombesin and verapamil hydrochloride (verapamil), a calcium channel blocker, on the incidence of peritoneal metastasis of intestinal adenocarcinomas induced by azoxymethane (AOM) and the labeling index of intestinal cancers were investigated in male Wistar rats.

METHODS

From the beginning of the experiment, rats were given 10 weekly subcutaneous injections of AOM (7.4 mg/kg body weight) and subcutaneous injections of bombesin (40 microg/kg body weight) every other day, and from week 16, intraperitoneal injections of verapamil (10 or 20 mg/kg body weight) every other day until the end fo the experiment in week 45.

RESULTS

Bombesin significantly increased the incidence of intestinal tumors and cancer metastasis to the peritoneum. Although verapamil administered at either dose had little or no effect on the enhancement of intestinal carcinogenesis by bombesin or on the location, histologic type, depth of involvement, labeling index, apoptotic index or tumor vascularity of intestinal cancers, it significantly decreased the incidence of cancer metastasis. Verapamil also significantly decreased the incidence of lymphatic invasion of adenocarcinomas, which was enhanced by bombesin.

CONCLUSION

These findings indicate that verapamil inhibits cancer metastasis through actions that do not affect the growth of intestinal cancers.

N-acetyl cysteine inhibits cell cycle progression in pancreatic carcinoma cells

The antioxidant N-acetyl cysteine (NAC) is a precursor of intracellular glutathione (GSH) and is also a well known as one of the chemopreventive agents which act through a variety of cellular mechanisms. We examined the effects of NAC on cell cycle progression in the pancreatic carcinoma cell lines, SW1990 and JHP1. Cells were incubated with or without NAC. Cell cycle distribution was analyzed by flow cytometry and immunoblotting. NAC suppressed cell proliferation in a concentration-dependent manner, whereas NAC increased intracellular glutathione content significantly in a dose-dependent manner. The percentage of cells in the G1 phase after treatment with NAC was significantly higher than the percentage seen for control cells. Cyclin D1 expression of carcinoma cells treated with NAC decreased remarkably compared with cells without NAC treatment. Thus, the antiproliferative effect of NAC by prolongation of the G1 phase in human pancreatic carcinoma cells shows its possible utility as an antitumor agent.

Relation between effective utilization of exogenous fat emulsion as energy substrate and oxygen metabolism after surgery

It is known that fat oxidation is increased in patients who have sustained surgical stress, but it is not clear whether fat emulsion should be administered during the early postoperative period. The aim of this study was to evaluate the utilization of exogenous fat emulsion after major surgery. Total parenteral nutrition composed of glucose/amino acids or glucose/amino acids/fat was administered for 6 days to 18 patients who had undergone esophagectomy. The caloric intake was significantly less than the resting energy expenditure (REE), and there was no difference in substrate utilization in either group up to postoperative day (POD) 2. After POD 4, fat utilization was significantly increased in the fat group. The total ketone body concentration was higher in the fat group than in the glucose group on POD 1 and 2. The arterial ketone body ratio (AKBR), which reflects the rate of turnover of the Krebs cycle, was positively correlated with the caloric intake/REE ratio. It was negatively correlated with the oxygen delivery index, oxygen consumption, and lactate concentration between POD 0 and POD 2. The lactate concentration was decreased and the AKBR was increased by POD 4. Fat emulsion was effectively utilized as energy substrate after POD 4, after the relative tissue hypoxia had improved and the AKBR had increased. The utilization of exogenous fat emulsion was closely related to deficient caloric intake and oxygen metabolism.

K-ras point mutation is associated with enhancement by deoxycholic acid of colon carcinogenesis induced by azoxymethane, but not with its attenuation by all-trans-retinoic acid

The effects of deoxycholic acid (DCA) with and without all-trans-retinoic acid (ATRA) on the incidence of colon tumors induced by azoxymethane, the incidence of K-ras point mutation in colon tumors and the labeling index of colon mucosa were investigated in male Wistar rats. Rats received 5 weekly injections of 7.4 mg/kg body weight of azoxymethane. From the start of the experiment, all rats in 3 groups also received chow pellets containing 0.3% DCA with and without s.c. injections of 0.75 or 1.5 mg/kg body weight of ATRA every other day until the end of week 45. Oral administration of DCA significantly increased the incidence of colon tumors in week 45. Concomitant use of DCA and ATRA at either dose significantly attenuated the enhancement by DCA of colon tumorigenesis. Administration of DCA significantly increased the incidence of K-ras point mutation in colon tumors and the labeling index in the colon mucosa. Combined administration of DCA and ATRA significantly reduced the labeling index of colon mucosa, which was increased by DCA, but did not affect the incidence of K-ras point mutation in colon tumors. These findings suggest that DCA enhances development of colon tumors and that this enhancement is attenuated by ATRA. A possible mechanism of this enhancement is induction of K-ras point mutation. However, decreased cell proliferation in the colon mucosa may be closely related to the attenuation of DCA-enhanced colon tumorigenesis, but not suppression of K-ras point mutation.

Effect of neoadjuvant chemotherapy for lymph node micrometastasis and tumor cell microinvolvement in the patients with esophageal carcinoma

Micrometastasis (MM) and tumor cell microinvolvement (TCM) in the lymph node were immunohistochemically evaluated using the cytokeratin (CK) antibody between a surgery group (n=20; 929 lymph nodes) and a chemotherapy group (n=20; 1052 lymph nodes). The incidence of MM+/-TCM in the surgery and chemotherapy groups was 50.0 (10/20) and 55.0% (11/20), respectively. Limiting the analysis to TCM alone revealed that the incidence in the chemotherapy group (10.0%; 2/20) was significantly lower than that in the surgery group (40.0%; 8/20; P=0.032). Preoperative chemotherapy in this regime was not effective, except for some patients with TCM alone.

Geranylgeranylated SNAREs are dominant inhibitors of membrane fusion

Exocytosis in yeast requires the assembly of the secretory vesicle soluble N-ethylmaleimide-sensitive factor attachment protein receptor (v-SNARE) Sncp and the plasma membrane t-SNAREs Ssop and Sec9p into a SNARE complex. High-level expression of mutant Snc1 or Sso2 proteins that have a COOH-terminal geranylgeranylation signal instead of a transmembrane domain inhibits exocytosis at a stage after vesicle docking. The mutant SNARE proteins are membrane associated, correctly targeted, assemble into SNARE complexes, and do not interfere with the incorporation of wild-type SNARE proteins into complexes. Mutant SNARE complexes recruit GFP-Sec1p to sites of exocytosis and can be disassembled by the Sec18p ATPase. Heterotrimeric SNARE complexes assembled from both wild-type and mutant SNAREs are present in heterogeneous higher-order complexes containing Sec1p that sediment at greater than 20S. Based on a structural analogy between geranylgeranylated SNAREs and the GPI-HA mutant influenza virus fusion protein, we propose that the mutant SNAREs are fusion proteins unable to catalyze fusion of the distal leaflets of the secretory vesicle and plasma membrane. In support of this model, the inverted cone-shaped lipid lysophosphatidylcholine rescues secretion from SNARE mutant cells.