[Surgical treatment of bronchial carcinoid: report of seven cases]

Seven patients with pulmonary carcinoid including three with typical carcinoid and four with atypical carcinoid were reported. There were 3 males and 4 females, with an age range of 37 to 80 years. All patients with typical carcinoid had pathological stage I. Of the patients with atypical carcinoid, one patient had stage I, two stage IIIA and one stage IIIB. All but two patients underwent lobectomy and mediastinal lymph node dissection. Bronchoplastic operation or right pneumonectomy were performed in the two patients. All but one patient underwent absolute or relative curative operation. Only one patient died on the 4th postoperative day. One patient with atypical carcinoid died of cancer recurrence 4 years after surgery. One patient died of breast cancer. One patient underwent surgery for metachronous multiple lung cancer, and he is doing well without recurrence. In conclusion, a limited operation is thought to be acceptable only in patients with typical carcinoid in a peripheral lesion without lymph node metastasis. Lobectomy and mediastinal lymph node dissection is necessary for the atypical carcinoid case.

Granulocyte-macrophage colony-stimulating factor upregulates matrix metalloproteinase-2 (MMP-2) and membrane type-1 MMP (MT1-MMP) in human head and neck cancer cells

Matrix metalloproteinase-2 (MMP-2) and membrane type 1-MMP (MT1-MMP) play an important role in the invasion and metastasis of head and neck squamous cell carcinoma (HNSCC), but the mechanism of their regulation is not clearly understood. Recently, granulocyte-macrophage colony-stimulating factor (GM-CSF) has been shown to be associated with cancer invasion and metastasis. We hypothesized that GM-CSF may upregulate MMP-2 and/or MT1-MMP expression in HNSCC cells, and may thereby influence their ability to invade and metastasize. We studied the effects of GM-CSF on the production of MMP-2 and MT1-MMP in HNSCC cell lines SAS and HSC-2. Gelatin zymography of conditioned media derived from HNSCC cells revealed a major band of 68 kDa, which was characterized as proMMP-2. GM-CSF stimulated the production of proMMP-2 in both cell lines in a dose-dependent manner. Treatment with 50 ng/ml GM-CSF for 24 h increased the proMMP-2 activity 3.4-fold in SAS cells and 2.3-fold in HSC-2 cells compared with untreated controls. Northern blot analyses demonstrated that GM-CSF led to elevated mRNA levels of MMP-2 and MT1-MMP in both cell lines. The results identify GM-CSF as a regulator of MMP-2 and MT1-MMP expression in certain types of HNSCC, and suggest that GM-CSF may contribute to the invasiveness of HNSCC through the regulation of MMP-2 and MT1-MMP expression.

Clinical significance of expression of membrane type 1 matrix metalloproteinase and matrix metalloproteinase-2 in human head and neck squamous cell carcinoma

Three different membrane-type matrix metalloproteinases (MT-MMPs) activate in vitro the latent form of matrix metalloproteinase-2 (MMP-2), which is one of the key proteinases in invasion and metastasis of various cancers. We examined the mRNA expression of MT1, 2, and 3-MMPs and MMP-2 in cell lines of head and neck squamous cell carcinoma (HNSCC) and quantitated the relative expression levels in human HNSCC tissues by Northern blotting. The tissue localization of MT1-MMP and MMP-2 was determined by immunohistochemistry and in situ hybridization. Their implications in clinicopathologic factors were statistically evaluated. All cell lines examined consistently expressed MT1-MMP and MMP-2, but not MT2, 3-MMP. In the clinical specimens, there was a significant correlation in coexpression of messenger of RNA (P = .0005) and colocalization by immunohistochemistry (P < .0001) for MT1-MMP and MMP-2. Relative mRNA expression levels of MT1-MMP and MMP-2 in the carcinoma tissues were significantly higher than those of the control tissues (P = .0045 and P = .0122, respectively). Both mRNA expression level and immunopositivity of MT1-MMP significantly correlated with lymph node metastasis (P = .0081 and P = .0193, respectively), which was confirmed by multivariate logistic regression analysis. Immunoreaction of MT1-MMP and its mRNA expression were observed in both carcinoma cells and stromal cells. The localization of MMP-2 closely corresponded to that of MT1-MMP. These observations suggest that MT1-MMP possesses a role as a determinant of lymph node metastasis in HNSCC, and that concurrent expression of MT1-MMP and MMP-2 are involved in progression of HNSCC.

[Curative laparoscopic surgery for early gastric cancer: eight years experience]

We have applied two different laparoscopic surgical techniques for early gastric cancer and have successfully treated 111 patients since March 1992. The indications are: 1) preoperative diagnosis of mucosal cancer; 2) lesion size of < 25 mm if the protruding type; and 3) lesion size < 15 mm and UI (-) if the depressed type. The first technique is laparoscopic wedge resection of the stomach using a lesion-lifting method (n = 93). The gastric wall around the cancerous lesion is exposed laparoscopically. The abdominal wall and gastric wall in the vicinity of the lesion are pierced using a 12-G sheathed needle. A small metal rod with a fine wire is introduced into the stomach through the outer sheath. By retracting the metal rod, the lesion can be lifted precisely (i.e., lesion-lifting method). Wedge resection at a sufficient distance from the metal rod is carried out using an endoscopic stapler. The second technique is referred to as laparoscopic intragastric mucosal resection (n = 18). Three balloon trocars are placed in the stomach laparoscopically. The stomach is then insufflated with CO2, and surgical instruments are introduced. The mucosal and submucosal layers around the lesion are resected with sufficient surgical margins. The selection of the laparoscopic technique depends on the site of the cancerous lesion. In our series of 111 patients, sufficient horizontal (mean 15 +/- 5 mm and 8 +/- 4 mm, respectively, using the first and second technique) and vertical surgical margins were achieved. There was no mortality and no major complications in patients undergoing either surgical technique. There have been two recurrences, both mucosal lesions found 2 years after the initial surgery, which were successfully treated with gastrectomy and laser irradiation. All patients have survived for 3 to 96 months, and there has been no trocar site recurrence. In conclusion, these laparoscopic procedures are curative and minimally invasive treatments for early gastric cancer.

[Sensitivity of UCN-01 lies in the balance of CDK 2 kinase and p21]

Five human cancer cell lines (MKN 45, HT-29, WiDr, PAN-3-JCK, and CRL 1420) were used to evaluate the antitumor spectrum of UCN-01, which suppressed the growth of these digestive cancer cell lines. A human pancreatic cancer xenograft (CRL 1420) and breast cancer xenograft (MX-1) were used to determine their sensitivity to UCN-01, in nude mice. UCN-01 significantly suppressed the tumor growth of CRL 1420 at a dose of 10 mg/kg in a schedule of (qd x 5) x 2, but was ineffective for MX-1. While p21 protein expression was induced by UCN-01 in both CRL 1420 and MX-1, an accumulation of dephosphorylated ppRb was observed only in CRL 1420, resulting in G1 block as detected by flow cytometric analysis. The CDK 2 activity of MX-1 was almost 6 times higher than that of CRL 1420, which might account for the resistance of MX-1 to UCN-01 in spite of the induction of p21 in this strain. We conclude that the determinant of sensitivity to UCN-01 lies in the balance of CDK 2 kinase activity and p21 protein induction.

Surgery for gastric carcinoma in patients more than 85 years of age

BACKGROUND

The incidence of gastric carcinoma is increasing in elderly patients. It has not been determined whether surgery improves the quality of life or prolongs survival in patients older than 85 years. This study was designed to evaluate surgery as a treatment option in patients more than 85 years of age.

METHODS

The records of 18 patients aged 85 to 91 years (mean 87.3 years), who underwent surgery for gastric carcinoma between 1983 and 1997 were analysed.

RESULTS

Three patients had multiple lesions. A total of 21 lesions were examined. Operative procedures included distal gastrectomy (n = 12), total gastrectomy (n = 4), proximal gastrectomy (n = 1), and laparoscopic wedge resection (n = 1). Perigastric lymphadenectomy was performed in 15 patients. No lymph node dissection was performed in three patients. Postoperative complications, including delirium, respiratory dysfunction, cardiac dysfunction, anastomotic leakage, bleeding, and ileus, occurred in 11 patients. There were two hospital deaths in patients who underwent emergency surgery. Survival was neither shortened nor prolonged by surgery as determined by life table analysis.

CONCLUSIONS

Surgical treatment should not be avoided based solely on the age of the patient, and quality of life in this population may be improved by surgery. Careful patient selection should include an assessment of the will to live.

Thoracoscopic treatment of primary chylopericardium

The development of video-assisted thoracoscopy has changed the practice of thoracic surgery. This report describes a 20-year-old man who successfully underwent thoracoscopic thoracic duct ligation and partial pericardiectomy for primary chylopericardium. We recommend a right-sided thoracoscopic approach to the thoracic duct in the lower thoracic cavity.

Jejunal limb obstruction caused by a cholesterol stone 15 years after a total gastrectomy and 20 years after a cholecystectomy: report of a case

We present herein the rare case of a 74-year-old woman found to have jejunal limb obstruction caused by a cholesterol stone 15 years after a total gastrectomy with Roux-en-Y anastomosis, and 20 years after a cholecystectomy. The patient complained of repeated episodes of upper abdominal distress on three separate occasions over a period of 20 months, and jejunal limb obstruction was diagnosed by abdominal computed tomography scanning and (99m)Tc scintigraphy. Surgery revealed a stone incarcerated in the jejunal limb, where the anastomosis had become slightly stenotic. The removed stone was 3.5 cm in diameter and was subsequently demonstrated to be a cholesterol stone by chemical analysis. This report is thought to be the first to describe jejunal limb obstruction caused by a gallstone incarcerated in the jejunal limb after a total gastrectomy in a patient with a history of cholecystectomy.

Gastrointestinal stromal tumors treated by laparoscopic surgery: report of three cases

Three cases of gastrointestinal stromal tumors (GIST) were treated by a laparoscopic wedge resection of the stomach. The tumor characteristics were confirmed to be nonepithelial, nonlymphomatous, nonmyogenic, and nonneurogenic gastrointestinal neoplasms with an uncertain origin which were CD34-positive and actin- and S-100-negative. The malignant potential was estimated based on the mitotic figures and growth rates. The results suggest that laparoscopic surgery is an adequate strategy for gastric submucosal tumors including GIST, and also indicates this technique to be a curative, safe, and minimally invasive procedure for both diagnosis and treatment.

The effect of FR167653 on pulmonary ischemia-reperfusion injury in rats

BACKGROUND

A novel synthesized organic compound, FR167653, has been characterized as a potent suppressant of interleukin-1 and tumor necrosis factor-alpha. We designed this experimental study to evaluate the effect of FR167653 on ischemia-reperfusion injury of the rat lung.

METHODS

Following general anesthesia, the left bronchus, pulmonary artery and vein were clamped for 1 hour. FR167653 was administered continuously beginning 30 minutes before the onset of ischemia and extending for 2 hours after reperfusion. Thirty-eight Wistar rats were divided into 4 groups according to the dose of FR167653 at the rate of 0.1, 0.05 and 0.025 mg/kg/hr in each group. After the optimal dose was obtained from the result of 1-week survival rate, the group with the optimal dose was compared with a control group by using such parameters as arterial oxygen saturation (SaO(2)), arterial oxygen tension (PaO(2)), cytokines, the expression of p38 MAP kinase and histologic study.

RESULTS

Survival rate of the group received FR at the rate of 0.1 mg/kg/hr (FR0.1 group) was best among the 4 groups. SaO(2) levels and PaO(2) levels after 2-hour of reperfusion were significantly (p < 0.05, respectively) higher in the FR0.1 group than in the control group. After 2-hour reperfusion, IL-1 beta was lower in the FR0.1 group than in the control group, and the expression of p38 MAP kinase was reduced in the FR0.1 group compared with the control group. In histologic study after 2-hour of reperfusion, alveolar damage with edema and interstitial thickening localized along the alveolar duct were observed in the control group, whereas these findings were remarkably less evident in the FR0.1 group.

CONCLUSIONS

We concluded that FR167653 ameliorates ischemia-reperfusion injury of the lung and may inhibit the production of proinflammatory cytokines by means of the inhibition of p38 MAP kinase.

Matrix metalloproteinase expression in cultured human gastric wall fibroblasts--interactions with Helicobacter pylori isolated from patients with ulcers

BACKGROUND

Matrix metalloproteinases (MMPs), enzymes capable of degrading collagens and other extracellular matrix components, have been implicated in gastric ulcer formation. However, the effect on MMP expression of Helicobacter pylori, also implicated in these lesions, has not been studied to our knowledge.

AIM

To seek links between H. pylori and MMP expression likely to affect gastric ulcer formation. After fibroblasts from human gastric wall were cocultured with H. pylori. concentrations of MMP-1 and -2 in the medium were determined by enzyme-linked immunosorbent assays.

RESULTS

Whereas MMP-1 was not detected in media from fibroblasts or H. pylori culture alone, MMP-1 was detected in cocultures (P<0.01). Similar amounts of MMP-2 were detected in medium from fibroblasts cultured alone and with H. pylori. No MMP-2 production by H. pylori cultured alone was detected.

CONCLUSIONS

MMP-1 appears to be important in gastric ulcer pathogenesis, and MMP-1 induction by H. pylori may impede gastric ulcer healing.

Activation of matrix metalloproteinase-2 in head and neck squamous cell carcinoma: studies of clinical samples and in vitro cell lines co-cultured with fibroblasts

We undertook this present study to investigate the activation of matrix metalloproteinase-2 (MMP-2) in human head and neck squamous cell carcinomas (HNSCC) tissues and cell lines. Gelatinolytic activities of active MMP-2 were significantly higher in carcinoma samples than in normal portions. Furthermore, the activation ratio of proMMP-2 significantly correlated with cervical lymph node metastasis. In vitro studies revealed an HNSCC cell line, HEp-2, to produce neither the pro form nor the active form of MMP-2, but human fibroblasts were found to produce proMMP-2. However, coculture of HEp-2 cells with fibroblasts resulted in the production of not only proMMP-2 but also activeMMP-2 in the culture medium. Northern blot analysis revealed a stronger expression of membrane-type 1 matrix metalloproteinase (MT1-MMP),which is a specific activator of MMP-2, mRNA in HEp-2 cells than in fibroblasts. These results suggest the activation of proMMP-2 as an important event in the process of HNSCC metastasis. They also suggest MMP-2 is secreted in its pro form by stromal fibroblasts surrounding the cancer cells and activated by MT1-MMP localized on the cancer cells.

[The validity of the sentinel node concept in gastrointestinal cancers]

Although the sentinel node concept has been validated and clinically applied to breast cancer and malignant melanoma, its clinical significance in other solid tumors has not been thoroughly investigated. With regard to gastrointestinal (GI) cancers in particular, our surgeons have been cautious because of the high frequency of skip metastasis and the complicated lymphatic system in the GI tract. We would like to emphasize that so-called skip metastasis has been defined according to anatomic classification of regional lymph nodes and that the lymphatic drainage route must be patient or lesion specific. To test the validity and feasibility of this concept in GI cancers, we have established a radio-guided intraoperative sentinel node navigation system using preoperative endoscopic submucosal injection of radioactive tracer followed by intra-operative gamma-probing. In 131 patients with GI cancers (esophagus: 22, stomach: 71, colorectum: 38), the detection rate of sentinel nades was 91% and overall diagnostic accuracy of lymph node metastasis by sentinel node status was 97%. Initial results suggest further investigation of this procedure as an accurate staging and a minimally invasive approach to early GI cancers.

Laparoscopic wedge resection of gastric submucosal tumors

Minimally invasive surgery has revolutionized the treatment of gastrointestinal tumors. Submucosal tumors (SMTs) of the stomach can be resected using laparoscopic techniques. Between 1993 and 1997, laparoscopic wedge resection was performed in 34 patients with an SMT of the stomach. The tumors ranged from 8 to 60 mm in diameter. All surgical margins were clear. The average operative time was 131 minutes. Most of the patients began eating on the first postoperative day and were discharged within 5 to 7 days. Histopathologic examination of the tumors showed gastrointestinal stromal tumor (n = 14), ectopic pancreas (n = 7), leiomyosarcoma (n = 4), schwannoma (n = 3), carcinoid (n = 2), leiomyoma (n = 2), an inflammatory lesion caused by parasites (n = 1), and cyst (n = 1). No recurrences were observed over the 5-year follow-up period. A solid SMT of the stomach larger than 20 mm in diameter can be treated using laparoscopic wedge resection.

Beneficial effects of novel nitric oxide donor (FK409) on pulmonary ischemia-reperfusion injury in rats

BACKGROUND

Nitric oxide (NO) seems to play an important role in tissue injury during reperfusion of the lung. FK409 is the first spontaneous NO donor that increases plasma guanosine 3':5'-cyclic monophosphate. It is reported that FK409 prevented myocardial infarction following occlusion and reperfusion in rat coronary arteries. In this study, we evaluated the effects of FK409 on pulmonary ischemia-reperfusion injury in an in situ warm ischemia model of rats.

METHODS

Animals were divided into 2 groups: the FK409 study group that was administered FK409 (0.4 mg/kg) before reperfusion and the control group, administered a saline vehicle only. Following a thoracotomy, the bronchus, pulmonary artery and vein were separately clamped for 1 hour. Arterial oxygen tension (PaO2), arterial oxygen saturation (SaO2), and endothelin-I (ET-I) were measured after 2 hours of reperfusion. Histologic and immunohistochemical studies were performed; polymorphonuclear neutrophils (PMNs) were counted after 2 hours of reperfusion.

RESULTS

PaO2, SaO2, ET-I after 2 hours of reperfusion and the 7-day survival rate were significantly (p < 0.05) better in the FK409 group than the control group. Histologic damage was reduced in the FK409 group compared with the control group. PMN infiltration was also significantly (p < 0.05) lower in the FK409 group than in the control group.

CONCLUSION

FK409 seems to protect against ischemia-reperfusion injury of the lung. This effect may be related to a homeostatic effect on pulmonary vascular beds and prevention of PMN sequestration.

Dependence of estrogenic activity on the shape of the 4-alkyl substituent in simple phenols

The ability of certain chemicals to mimic the effects of natural steroid hormones and their potential to disrupt the delicate balance of the endocrine system in animals has attracted much interest in recent years. Alkylphenolic chemicals have been reported to be weakly estrogenic. Estrogen receptor (ER) binding is primarily the result of interaction of the receptor with both a phenolic residue, and a hydrophobic pharmacophore. We have prepared and screened various phenols having a bulky 4-alkyl group, which may interact hydrophobically with the receptor, for estrogenic activity by using a previously described reporter gene assay employing COS-1 cells transfected with rat ER alpha-expression plasmid and an appropriate reporter plasmid. Some of the tested compounds, such as 4-(1-adamantyl)phenol and 4-cycloalkylphenols, exhibited much more potent activity than the typical estrogenic alkylphenol, 4-tert-octylphenol.

Dihydropyrimidine dehydrogenase and messenger RNA levels in gastric cancer: possible predictor for sensitivity to 5-fluorouracil

We investigated the correlation between tumor sensitivity to 5-fluorouracil (5-FU) and enzymatic activities of thymidylate synthetase (TS) and dihydropyrimidine dehydrogenase (DPD) in human gastric cancer specimens. Forty-one patients with advanced gastric cancer gave informed consent and were enrolled in the study. Biopsy specimens of gastric cancer were obtained preoperatively through gastrofiberscopy and used to determine TS and DPD messenger RNA (mRNA) levels. TS and DPD enzyme activity and mRNA levels were also measured in resected tumor tissue samples obtained after surgical resection. TS and DPD activity were measured using the TS-binding assay and a radioenzymatic assay, respectively, while mRNA levels were measured by semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR), with co-amplification of glyceraldehyde-3-phosphate dehydrogenase (GAPDH) as an internal standard. 5-FU sensitivity of resected tumor specimens was measured by the tetrazolium-based colorimetric assay (MTT assay). Both TS and DPD mRNA levels correlated well between biopsied and resected tumor specimens. A statistically significant correlation was also observed between mRNA levels in biopsied specimens and enzymatic activities in resected specimens. DPD levels significantly correlated with 5-FU sensitivity, such that high DPD activity and high DPD mRNA levels resulted in low sensitivity to 5-FU. In contrast, no correlation was observed between TS activity or TS mRNA levels and 5-FU sensitivity. We conclude that tumor DPD mRNA level, as assessed from biopsy specimens obtained by gastrofiberscopy, may be a useful indicator in predicting tumor sensitivity to 5-FU in patients with gastric cancer.

Hemodynamic effects of alpha-human atrial natriuretic polypeptide on patients undergoing open-heart surgery

BACKGROUND

A cardiac hormone, alpha-human atrial natriuretic polypeptide (alpha-hANP), acts as a vasodilator and a diuretic by activating cyclic GMP formation. We studied the hemodynamic effects of continuous intravenous infusion of alpha-hANP on patients undergoing open-heart surgery.

METHODS

A total of 15 patients, including 7 with CABG, 4 with AVR, 2 with CABG plus AVR, and 2 with AVR plus MVR were involved in the study. They underwent open-heart surgery in our institute between July 1996 and April 1997. The mean age of patients was 68 years, ranging from 63 to 77. A dosage of 0.05 microg/kg/min of alpha-hANP was administered to all patients on postoperative day 1. Hemodynamics and blood and urine samples were measured at the following times: 2 hours before continuous intravenous infusion of alpha-hANP, 0, 1, 2, 3, 6, 12 and 24 hours after continuous intravenous infusion. We concomitantly measured urine volume and the plasma concentration of alpha-hANP.

RESULTS

The plasma concentration of alpha-hANP increased sufficiently after the beginning of continuous intravenous infusion without any side effects, and the urine volume increased too. The administration of alpha-hANP induced a decrease in central venous pressure, pulmonary capillary wedged pressure and the pulmonary vascular resistance index. Systemic vascular resistance index and cardiac output remained unchanged.

CONCLUSIONS

It is useful for the management of patients with associated volume overload following open-heart surgery because the administration of alpha-hANP decreases preload and facilitates satisfactory urination.

Carbon dioxide insufflation aids video-assisted thoracic surgery in a young child

A 3-year-old girl with pectus excavatum successfully underwent exploration using video-assisted thoracic surgery. A complete pericardial defect was identified. The lung was kept totally collapsed during the procedure using low-flow (1 L/min), low-pressure (7 mmHg) carbon dioxide insufflation. This technique is expected to be a safe adjunct to thoracoscopic procedures in infants and small children.

Thymidylate synthetase and dihydropyrimidine dehydrogenase levels in gastric cancer

The measurement of thymidylate synthetase (TS) and dihydropyrimidine dehydrogenase (DPD) enzymatic activities and mRNA levels in tumors may be useful in predicting tumor sensitivity to 5-fluorouracil (5-FU). Forty-one patients with advanced gastric cancer gave informed consent and were enrolled in this study. Biopsy specimens of gastric cancer were obtained preoperatively through gastrofiberscopy and used to determine TS and DPD mRNA levels. We also measured TS and DPD enzymatic activities and mRNA levels in surgically resected gastric cancer samples, as well as in adjacent normal gastric mucosa. TS and DPD activities were measured using the TS-binding assay and a radioenzymatic assay, respectively, while mRNA levels were measured by semi-quantitative reverse transcription-PCR (RT-PCR) co-amplified with glyceraldehyde-3-phosphate dehydrogenase (GAPDH) as an internal standard. In resected tumor specimens, TS and DPD activities ranged from 7.1 to 176.6 fmol/mg protein and from 3.6 to 99.8 pmol/min/mg protein, respectively, while TS and DPD mRNA levels ranged from 0.50 to 21.12 and from 0.014 to 7:22, respectively. There were no significant correlations between TS/DPD levels and other clinicopathological factors, except for low DPD mRNA levels in undifferentiated carcinoma. Both TS activity and mRNA levels were significantly higher in tumor tissues compared to normal adjacent mucosa. In contrast, there was no significant difference between tumoral and non-tumoral DPD activity, although tumor tissue showed significantly lower DPD mRNA levels than non-tumoral tissue. High tumoral TS mRNA levels in preoperative biopsy specimens from patients with stage III/IV was associated with poor survival outcome after surgery compared with patients with low tumoral TS mRNA levels. In contrast, DPD levels had no influence on prognosis. We conclude that high tumoral TS levels and low tumoral DPD mRNA may indicate the selective cytotoxicity of 5-FU on gastric cancer, and that tumoral TS mRNA levels may be a prognostic factor for patients with stage III/IV gastric cancer.

Chemosensitivity testing of primary tumor cells from gastric cancer patients with liver metastasis can identify effective antitumor drugs

The liver metastasis of gastric carcinoma is resistant to conventionally available treatment. Twenty patients with liver metastasis of gastric cancer were treated by arterial drug infusion using a reservoir and seven cases were treated with systemic chemotherapy. The resected primary gastric cancer specimen was used for chemosensitivity assay with 3-(4,5-dimethylthiazol-2yl)-2,5-diphenyl-2H tetrazolium bromide (MTT) endpoint, and the patients were treated without reference to the results of the chemosensitivity assay. The mean survival period was assessed according to the histology of the primary lesion, the grade of liver metastasis and, the presence of peritoneal dissemination. No significant differences were observed in the primary tumor histology and grade of liver metastasis, but the survival period of the patients with liver metastasis and peritoneal dissemination was significantly shorter than that of the patients without peritoneal dissemination. Nine patients were treated with drugs that were effective in the chemosensitivity assay, and their responses included two complete responses and two partial responses; these patients showed a significantly prolonged survival period compared with patients treated with drugs that were not effective in the assay. The chemosensitivity assay is useful for evaluating the effectiveness of antitumor agents against liver metastasis of gastric cancer.

Chemosensitivity test is useful in evaluating the appropriate adjuvant cancer chemotherapy for stage III non-scirrhous and scirrhous gastric cancers

A total of 183 cases with gastric cancer was retrospectively analyzed in terms of their chemosensitivity as determined by the 3-(4,5-dimethylthiazol-2yl)-2,5-diphenyl-2H tetrazolium bromide (MTT) assay and their survival rates after surgery. After the patients were stratified into scirrhous or non-scirrhous carcinoma groups, they were tested for stage III or IV gastric cancer. In these four cohorts, the patients were categorized into sensitive and insensitive groups determined by the MTT assay. The sensitive group was treated with at least one drug that had been shown to be effective in the MTT assay, and the insensitive group was given a drug that had been shown to be ineffective in the MTT assay. In stage III gastric cancer, the sensitive group showed a favorable survival compared to the insensitive group in scirrhous and non-scirrhous carcinoma, while this difference was diminished in stage IV gastric cancer. There were no survival benefits in the sensitive group in stage III gastric cancer, when they were not treated with adjuvant cancer chemotherapy. These results suggested that MTT assay would be useful in evaluating the appropriate adjuvant cancer chemotherapy for stage III scirrhous and non-scirrhous gastric cancer.

[Establishment of alpha-fetoprotein producing human rectal cancer cell line (RKK-YK) and its features]

We succeeded in establishing a rectal cancer cell line RKK-YK from the primary lesion in a patient with rectal cancer. It took 36.2 hours for duplication. We were able to transplant the RKK-YK cell line to nude mice at a transplantation rate of 50%. The transplanted tumor exhibited histological features similar to those of the primary lesion. Cancer cells with two different degrees of differentiation, in which features of moderately differentiated adenocarcinoma and well-differentiated adenocarcinoma were observed together, were established. The levels of the tumor markers (CEA, CA19-9 and AFP) were elevated in the supernatant of the culture solution and the serum of the nude mice over time course. In the immunohistological examination of the transplanted tumor, anti-CEA, anti-CA19-9 and anti-AFP antibodies were positively stained. Molecular biological analysis revealed nor point mutation or deletion in K-ras gene exon 1 and 2, p53 gene exon 5 to 11 or MCC.

Interferon gamma increases the antitumor activity of mitomycin C against human colon cancer cells in vitro and in vivo

A combined antitumor activity of mitomycin C (MMC) and interferon gamma-1a (IFN-gamma) was evaluated to be synergistic by the 3-(4, 5-dimethylthiazol-2yl)-2,5-diphenyl-2H tetrazolium bromide assay and human tumor xenografts/severe combined immunodeficient (SCID) mouse system using colon cancer cell lines. The experimental metastasis of WiDr cells in SCID mouse was inhibited by MMC and IFN-gamma with their synergism. Intracellular uptake of MMC in WiDr cells in vitro was significantly increased by IFN-gamma, suggesting the mode of synergism of these agents. This model may also partly explain the antitumor activity of combined MMC, 5-fluorouracil and interleukin-2 treatment on hepatic metastasis of colon cancer.

Dihydropyrimidine dehydrogenase activity and messenger RNA level may be related to the antitumor effect of 5-fluorouracil on human tumor xenografts in nude mice

We investigated the correlation between tumor sensitivity to 5-fluorouracil (5-FU) and the enzymatic activity and mRNA levels of thymidylate synthetase (TS) and dihydropyrimidine dehydrogenase (DPD) using human tumor xenografts in nude mice. Three gastric carcinoma xenografts (SC-1-NU, St-4, and H-111), two colon carcinoma xenografts (Co-4 and Col-3-JCK), one pancreatic carcinoma xenograft (PAN-3-JCK), and one breast carcinoma xenograft (MX-1) were inoculated into nude mice. When the resultant tumors reached 100-300 mg, 5-FU was administered i.p. at a dose of 60 mg/kg in a schedule of three times every 4 days, and the antitumor activity of 5-FU was evaluated as the relative mean tumor weight in treated mice compared to control mice. Xenografts were also inoculated into untreated nude mice. When tumors weighed 200-300 mg, tumor tissues were resected for measurement of tumoral TS and DPD. TS and DPD activities were detected by the TS-binding assay and a radioenzymatic assay, respectively. mRNA levels were measured by semiquantitative reverse transcription-PCR, with glyceraldehyde-3-phosphate dehydrogenase coamplified as an internal standard. TS and DPD activities ranged from 84.7 to 775.5 fmol/mg protein and from not detectable to 79.7 pmol/min/mg protein, respectively. TS and DPD mRNA levels ranged from 0.51 to 9.90 and from not detectable to 0.93, respectively. The enzymatic activities of TS and DPD were correlated with observed mRNA levels. DPD levels were significantly correlated with 5-FU sensitivity, with high DPD activity and high DPD mRNA level resulting in low sensitivity to 5-FU. In contrast, no correlation between TS level and 5-FU sensitivity was observed. Tumoral DPD activity and DPD mRNA level may be useful indicators in predicting the antitumor activity of 5-FU.

[A case of esophageal cancer with excellent response to oral UFT treatment]

The patient was an 83-year-old Japanese male with the chief complaint of difficulty in swallowing. On Feb. 24, 1997, he was referred to our hospital under suspicion of esophageal cancer. X-P revealed an image of a protrusion at Im-Iu having a long diameter of 6 cm. Endoscopy revealed that the esophageal lumen was nearly completely obstructed due to the presence of an irregularly-shaped tumor. The pathological finding of biopsized specimen was a squamous cell carcinoma. Thus, this case was diagnosed as esophageal cancer, but surgery was deemed inappropriate due to the patient's advanced age. Accordingly, on March 12, treatment was started with oral administration of UFT-E granules (Tegafur, 450 mg/day). Initially, the patient was unable to ingest even liquids, but beginning around May the blockage of the esophagus disappeared. Endoscopic examination performed in June revealed that the tumor had shrunk to a about 1 cm in diameter. Although tumor tissue remained, the tumor was observed to have undergone further reduction in size at 6 months after the start of chemotherapy. Moreover, the patient gained weight. This is considered to be a very rare case of an excellent response of esophageal cancer to oral administration of only UFT agents.

Sealing effect of rapidly curable gelatin-poly (L-glutamic acid) hydrogel glue on lung air leak

BACKGROUND

Air leak is a problem commonly occurring in lung and thoracic operations. In this study, a rapidly curable hydrogel glue was prepared as the seal for lung air leak.

METHODS

Mixing an aqueous solution of gelatin and poly(L-glutamic acid) with a water-soluble carbodiimide produced a hydrogel. The sealing effect on the air leak wound of rat lung was compared with that of conventional fibrin glue.

RESULTS

The gelatin-poly(L-glutamic acid) hydrogel glue was solidified as rapidly as the fibrin glue, and was significantly more effective in sealing the lung air leak than the fibrin glue. Approximately 80% of the lungs treated with the hydrogel glue exhibited no air leak at the lung pressure of 50 cm H2O. Urea addition could prevent spontaneous gelatination of the mixed solution at room temperature and did not affect the hydrogel sealing effect. The bonding strength of the hydrogel glue both with and without urea to the lung tissue was significantly higher than that of the fibrin glue.

CONCLUSIONS

We concluded that this strong lung adhesion of the gelatin-poly(L-glutamic acid) hydrogel glue resulted in its superior sealing effect.

Impaired lung oxygenation in acute aortic dissection

BACKGROUND

In the early phase after the onset of acute aortic dissection, oxygenation impairment often occurs. However, the etiology and clinical course of this phenomenon have not been established. We examined the serial changes of oxygenation, inflammatory reaction and laboratory data in patients with acute aortic dissection.

METHODS

Nine patients (DeBakey type I; 4, type II; 3 and type IIIb; 2), aged 46 to 82 years were included in this study. All patients were managed in the intensive care unit, and systolic arterial pressure was maintained at around 110 to 120 mm Hg. Oxygenation was impaired in all patients, three (33%) of whom required mechanical ventilatory support.

RESULTS

Pleural effusion was observed in eight (89%) of nine patients. Respiratory index was 0.98+/-0.19 (mean +/-SEM) at the time of admission, and elevated to 1.59+/-0.35, 1.58+/-0.21, 1.60+/-0.28 respectively, at day 1, 2 and 3. Oxygenation index was 318+/-34 at the time of admission, and decreased to 271+/-34, 255+/-19, 263+/-26, respectively, at day 1, 2 and 3. These values recovered to normal after day 4. The increase of white blood cells and high fever (>38 degrees C) continued until day 3. Platelet counts recovered after day 4. The serum bilirubin level was highest (2.0+/-0.5 mg/dl) at day 3, and decreased gradually after day 4. In two recent patients whose serum interleukin-8 (IL-8) was measured, IL-8 levels increased according to the impaired oxygenation or aneurysmal enlargement. Impaired oxygenation, inflammatory changes, platelet consumption and bilirubin elevation continued until day 3 and resumed normal levels after day 4.

CONCLUSIONS

These changes may be due to hemolysis, consumption coagulopathy or inflammation associated with acute aortic dissection. IL-8 elevation may be associated with aneurysmal enlargement and these phenomena.

Acinar flow irreversibility caused by perturbations in reversible alveolar wall motion

Mixing associated with "stretch-and-fold" convective flow patterns has recently been demonstrated to play a potentially important role in aerosol transport and deposition deep in the lung (J. P. Butler and A. Tsuda. J. Appl. Physiol. 83: 800-809, 1997), but the origin of this potent mechanism is not well characterized. In this study we hypothesized that even a small degree of asynchrony in otherwise reversible alveolar wall motion is sufficient to cause flow irreversibility and stretch-and-fold convective mixing. We tested this hypothesis using a large-scale acinar model consisting of a T-shaped junction of three short, straight, square ducts. The model was filled with silicone oil, and alveolar wall motion was simulated by pistons in two of the ducts. The pistons were driven to generate a low-Reynolds-number cyclic flow with a small amount of asynchrony in boundary motion adjusted to match the degree of geometric (as distinguished from pressure-volume) hysteresis found in rabbit lungs (H. Miki, J. P. Butler, R. A. Rogers, and J. Lehr. J. Appl. Physiol. 75: 1630-1636, 1993). Tracer dye was introduced into the system, and its motion was monitored. The results showed that even a slight asynchrony in boundary motion leads to flow irreversibility with complicated swirling tracer patterns. Importantly, the kinematic irreversibility resulted in stretching of the tracer with narrowing of the separation between adjacent tracer lines, and when the cycle-by-cycle narrowing of lateral distance reached the slowly growing diffusion distance of the tracer, mixing abruptly took place. This coupling of evolving convective flow patterns with diffusion is the essence of the stretch-and-fold mechanism. We conclude that even a small degree of boundary asynchrony can give rise to stretch-and-fold convective mixing, thereby leading to transport and deposition of fine and ultrafine aerosol particles deep in the lung.

Curative laparoscopic surgery for early gastric cancer: five years experience

Sixty-one patients who were diagnosed with mucosal gastric cancer have been successfully treated with two laparoscopic techniques at our institute from March 1992 to March 1997. One is laparoscopic wedge resection of the stomach using a lesion-lifting method for lesions of the anterior wall, the lesser curvature, and the greater curvature of the stomach. The other is laparoscopic intragastric mucosal resection for lesions of the posterior wall of the stomach and near the cardia or the pylorus. Indications are as follows: (1) preoperatively diagnosed mucosal cancer; (2) <25 mm diameter elevated lesions; and (3) <15 mm diameter depressed lesions without ulcer formation. Patients were discharged in 4 to 8 days uneventfully. There was no major complication or mortality. The resected specimens had sufficient surgical margins horizontally (16 +/- 5 and 8 +/- 4 mm, respectively) and vertically. In one patient histologic examination revealed slight tumor infiltration into the submucosal layer with lymphatic invasion. He underwent gastrectomy with lymph node dissection 1 month after surgery. Otherwise, histologic examination revealed curative surgery. All patients in the series have survived during the 4- to 65-month follow-up period. There have been two recurrences in the series, both of which were found near the staple line 2 years after the initial surgery and were still mucosal lesions. They were successfully treated by open gastrectomy and laser irradiation. A separate early gastric cancer was found 2 years after the initial surgery in one patient, who then underwent curative open gastrectomy. In conclusion, if the patients are selected properly, these laparoscopic procedures are curative, minimally invasive treatment for early gastric cancer.

Preventive effect of matrix metalloproteinase inhibitor, R-94138, in combination with mitomycin C or cisplatin on peritoneal dissemination of human gastric cancer cell line TMK-1 in nude mice

R-94138, a matrix metalloproteinase inhibitor, was examined for the ability to prevent peritoneal dissemination of a human gastric cancer xenograft, TMK-1. When the supernatant of a co-culture of TMK-1 cells and human normal fibroblast cells was subjected to gelatin zymography, it was clear that the protein expression of MMP-2 had been inhibited by R-94138. When TMK-1 was injected intraperitoneally (i.p.) into nude mice at 5 x 10(5) cells/body, the resulting peritoneal dissemination mimicked clinical carcinomatous peritonitis. When the maximum tolerated dose of mitomycin C (MMC) or cisplatin (DDP) was given 12 h after the tumor inoculation, peritoneal dissemination was completely inhibited, while the effect of R-94138 was limited when it was given i.p. at a dose of 20 mg/kg in a schedule of q.d. x 5 starting 12 h after tumor injection. MMC and DDP also suppressed peritoneal dissemination when they were administered 1 week after the tumor inoculation at a single dose of 2 and 3 mg/kg i.p., respectively. R-94138 inhibited peritoneal dissemination when it was administered i.p. at a dose of 30 mg/kg in a schedule of q.d. x 5 starting from 1 week after tumor injection. The combination of MMC and R-94138 increased the preventive effect on peritoneal dissemination. R-94138 seems to be a promising candidate to prevent peritoneal dissemination of gastric cancer.

Management of primary gastric lymphomas from a surgeon's viewpoint

Primary gastric lymphoma is a relatively uncommon disease and controversy still exists over its management. In order to assess prognostic factors of lymphomas, we carried out a retrospective study of 28 surgically treated gastric lymphoma patients. The overall survival rate for all the patients in the study was 33% at 10 years. On univariate analysis, lymph node metastasis and depth of tumor infiltration proved to be a significant prognostic factor while size and location of tumor, sex, and method of resection was not. From our results we believe that gastric lymphoma can be regarded as a localized disease in the early stages and a curative resection can be attained when aggressive surgery is possible.

Combined antitumour activity of mitomycin C, 5-fluorouracil and interleukin-2 against human colon cancer cells

Combined treatment of interleukin-2 (IL-2), 5-fluorouracil (5-FU) and mitomycin C (MMC) is reported to be effective against hepatic metastasis of colon carcinoma. To clarify this modality, we investigated lymphokine activated killer (LAK) activity of human peripheral lymphocytes on colon cancer cell lines by 51Cr release assay. LAK activity against Colo 205 cells by untreated lymphocytes was 12%, which increased to 25% upon the addition of 5-FU, but remained unchanged upon the addition of MMC. The combined antitumour activity of MMC or 5-FU with or without LAK-supernatant was evaluated by MTT assay; antitumour activity of MMC was increased by the addition of LAK-supernatant. The concentration of interferon-gamma (IFN-gamma) and tumour necrosis factor-alpha (TNF-alpha) was increased in LAK-supernatant, and the antitumour activity of combined IFN-gamma and MMC was synergistic. The mechanism of this therapy seemed to be associated with both increased LAK activity by 5-FU and increased antitumour activity of MMC with IFN-gamma.

Characteristics of Helicobacter pylori strains isolated from patients with different gastric diseases

The pathogenesis of chronic gastritis, gastric ulcer, duodenal ulcer, gastric cancer, and remnant gastritis is considered to be related to infection by Helicobacter pylori. The purpose of this study was to investigate the characteristics of H. pylori strains isolated from patients with various gastric diseases. Fifty strains of H. pylori were clinically isolated at Keio University Hospital and were assessed for (i) vacuolating cytotoxin (VT) production, by cytotoxic assay using rabbit kidney (RK) 13 cells; (ii) the expression of cytotoxin associated gene (cagA), by polymerase chain reaction; and (iii) motility on a semi-solid plate. Positivity for VT production by H. pylori strains isolated from patients with chronic gastritis, gastric ulcer, duodenal ulcer, gastric cancer, and remnant gastritis, was 100%, 89%, 92%, 100%, and 60%, respectively. There was no significant difference in the incidence of positivity for cagA among the strains isolated from different gastric diseases. Swarming distances, which indicate motility of H. pylori strains, were 12.7, 13.2, 12.8, 16.6 and 9.2mm in strains from chronic gastritis, gastric ulcer, duodenal ulcer, gastric cancer, and remnant gastritis, respectively, with H. pylori isolated from remnant gastritis showing significantly less motility than H. pylori isolates from other diseases. There were no significant differences in VT production and cagA positivity among the H. pylori strains.

Effect of additives on gelation and tissue adhesion of gelatin-poly(L-glutamic acid) mixture

Gelation and tissue adhesion of mixtures of gelatin and poly (L-glutamic acid) (PLGA) aqueous solution were investigated in the presence of additives following the addition of a water-soluble carbodiimide (WSC) that induced chemical cross linking between gelatin and PLGA. To prevent spontaneous gelation of the mixed solution through physical cross linking between gelatin molecules at room temperature, additives were added to the mixed solution. Among the additives studied, starch and urea were effective in preventing the spontaneous physical gelation. The mixed gelatin and PLGA solution set to a cross-linked hydrogel within scores of second by WSC addition, irrespective of the presence of urea, whereas the viscosity of the solution with added starch was too high to measure the gelation time. The cross-linked gelatin-PLGA hydrogels with and without urea showed higher bonding strength to soft tissues than fibrin glue. This was in marked contrast to gelatin-PLGA hydrogels with soluble starch. Irrespective of the presence of urea, the gelatin-PLGA hydrogels gradually biodegraded in the back subcutis of mice over 3 months and no severe inflammatory response to the hydrogels was observed. These findings indicate that urea is promising as an additive to prevent spontaneous physical gelation of the mixed gelatin and PLGA aqueous solution without changing the characteristics of WSC-induced cross linking and tissue adhesion of the formed hydrogel.

[A clinical study on the cases of ischemic colitis: comparison of clinical images based on time from onset of the disease to detection of bloody stool]

A study was performed on 28 cases of ischemic colitis. The patients were divided into three groups: Group A (9 cases with bloody stool detected within 2 hours after the onset of abdominal pain), Group B (7 cases with bloody stool detected in 2 to 6 hours), and Group C (12 cases with bloody stool detected after more than 6 hours). These cases were comparatively studied. Variables used were as follows: (1) age, (2) sex, (3) constipation, (4) vomiting, (5) peak value of WBC count (/microliter) after admission, (6) peak value of log CRP (microgram/dl), (7) presence of ulcerative lesion in endoscopic findings in acute stage. Using Group A B and C as classification variables, canonical discriminant analysis was performed. As a result, clear linearity was recognized in Group A-->B-->C, and the values (5), (6) and (7) were extracted as the corresponding variables. For these variables, significant difference was also noted in multivariate analysis of covariance. These results suggest that it is possible to predict the severity of the disease to some extent as represented by objective markers of inflammation by finding the time from onset of abdominal pain to detection of bloody stool.

Hemostatic capability of rapidly curable glues from gelatin, poly(L-glutamic acid), and carbodiimide

The hemostatic capability of rapidly curable glues composed of gelatin and poly(L-glutamic acid) (PLGA) was compared with that of the conventional fibrin glue. The hydrogels produced from mixed gelatin and PLGA aqueous solution within several seconds by addition of water-soluble carbodiimide (WSC) was applied to the dog spleen injured by needle pricking. The WSC-catalyzed gelatin-PLGA glues exhibited higher hemostatic capability than the fibrin glue. The total amount of bleeding from the injured spleen until hemostasis when the gelatin-PLGA hydrogel glues were applied was significantly smaller than that of the fibrin glue application. The gelatin-PLGA glue application enhanced the success rate of complete hemostasis to a significantly greater extent than the fibrin glue, while the frequency of glue applications until achieving complete hemostasis decreased. The gelatin PLGA hydrogels strongly adhered to the surface of dog spleen, whereas the fibrin hydrogel was easily detached from the spleen surface. It was concluded that this strong adhesion mechanically suppressed the bleeding, leading to enhanced hemostasis by the rapidly curable gelatin-PLGA glues.

Selective antitumor activity of MKT-077, a delocalized lipophilic cation, on normal cells and cancer cells in vitro

BACKGROUND AND OBJECTIVES

1-Ethyl-2-¿[3-ethyl-5-(3-methylbenzothiazolin-2-yliden)]-4-+ ++oxothiazolidin-2-ylidenemethyl¿pyridium chloride (MKT-077, formerly known as FJ776), a delocalized lipophilic cation, is known to accumulate in the mitochondria, according to the negative potential inside the mitochondria, and exert its cytotoxicity.

METHODS

The single-cell suspensions of human cancer cell lines, human spleen cells, and fresh cancer specimens obtained from patients with gastric carcinoma were used for the 3-(4,5-dimethylthiazol-2yl)-2,5-diphenyl-2H tetrazolium bromide (MTT) assay.

RESULTS

The antitumor activity of MKT-077 was dose and concentration related, and 50% inhibitory concentrations (IC50) ranged from 1.7 to 14.3 microg/ml, with a mean +/- standard deviation (SD) of 8.4 +/- 4.6 microg/ml. The IC50 of fresh surgical spleen-cell specimens ranged from 0.34 microg/ml to >100 microg/ml in a 48 h incubation, with a mean +/- SD of 66.5 +/- 37.7 microg/ml. When the antitumor activity of MKT-077 was compared between gastric cancer cells and spleen cells obtained from the same patient, the concentration-dependent antitumor activity of this agent was obvious in the cancer cells, while no significant cytotoxicity was observed in the spleen cells. The fresh surgical specimens of gastric cancer showed higher sensitivity to MKT-077 than did spleen cells at a concentration of 30 microg/ml, with a statistically significant difference at P < 0.05.

CONCLUSIONS

The selective antitumor activity of MKT-077 was confirmed using fresh surgical specimens and warrants further investigation.