Cancer cells isolated from malignant pleural and peritoneal effusions inhibit phospholipase A2 activity in human polymorphonuclear leukocytes.

We studied the influence of cancer cells on the LTB4 production by human polymorphonuclear leukocytes (PMN). The cancer cells were isolated from malignant pleural effusion specimens taken from two patients or from a peritoneal effusion specimen of one patient. While human PMN produced LTB4 following stimulation with A23187, the addition of cancer cells inhibited LTB4, 5-HETE and 12-HETE production by PMN in a cell number-dependent manner, while the cancer cell lines also showed a similar inhibition. The addition of lysate of the breast cancer cells also inhibited in a dose-dependent manner the production of LTB4 by PMN following stimulation with A23187. The addition of arachidonic acid completely reversed the inhibition of PMN-LTB4 production by the addition of the breast cancer cell lysates, thus suggesting inhibition at the phospholipase A2 level. The addition of this lysate to the partially purified human cytosolic PLA2 also inhibited the PLA2 activity. In contrast, the addition of lymphoma cells isolated from metastatic lymphnodes did not inhibit the LTB4 production from PMN. Since LTB4 is one of the important chemotactic factors for PMN and monocytes, these findings suggest that the inhibition of the PLA2 activity by the cancer cells thus results in a reduced production of LTB4 from PMN and contributes to a predisposition to develop severe infection in patients with advanced cancer.

Vascular endothelial growth factor and platelet-derived growth factor are potential angiogenic and metastatic factors in human breast cancer.

BACKGROUND: Angiogenesis is a prerequisite for tumor growth and metastasis. Tumor angiogenesis may be mediated by several angiogenic factors such as vascular endothelial growth factor (VEGF), platelet-derived growth factor (PDGF), transforming growth factor-alpha, and basic fibroblast growth factor. METHODS: Differential mRNA expressions of VEGF, PDGF (A chain), transforming growth factor-alpha and basic fibroblast growth factor in 32 primary invasive breast tumors were examined by reverse transcriptase-polymerase chain reaction. We analyzed relationships between mRNA expressions of these angiogenic factors and the degree of angiogenesis, tumor size, and metastasis. Quantification of angiogenesis was achieved by the immunohistochemical staining of endothelial cells with antibody to CD31. RESULTS: VEGF and PDGF-A mRNAs were expressed more frequently in breast tumors than in nontumor breast tissues, whereas no difference was found in expression frequency of either transforming growth factor-alpha or basic fibroblast growth factor mRNA. Vascular counts in tumors correlated with each expression frequency of VEGF and PDGF-A mRNA. PDGF-A mRNA was expressed more frequently in tumors with lymph node metastasis than in those without metastasis. CONCLUSIONS: Expression of VEGF and PDGF mRNAs detected by reverse transcriptase-polymerase chain reaction in breast tumors correlates with tumor-related characteristics of angiogenesis and metastatic potential. Analysis of these mRNAs by reverse transcriptase-polymerase chain reaction may be useful for assessing the biologic behavior of a breast tumor before surgical treatment.

Induction of inflammatory cytokines in effusion cavity by OK-432 injection therapy for patients with malignant effusion: role of interferon-gamma in enhancement of surface expression of ICAM-1 on tumor cells in vivo.

The intracavitary injection of OK-432, a streptococcal preparation, has been shown to be an effective immunotherapy for patients with malignant effusion. We found that this therapy increases surface expression of intercellular adhesion molecule-1 (ICAM-1) on tumor cells, and that the degree of increased ICAM-1 was correlated with therapeutic effects. In the present study, we investigated the ability of OK-432-induced inflammatory cytokines, such as interferon-gamma (IFN-gamma), tumor necrosis factor-alpha (TNF-alpha), and interleukin-1 beta (IL-1 beta), to enhance ICAM-1 expression. We treated 17 patients who had a malignant effusion with OK-432. At 24 hr after OK-432 injection, ICAM-1 levels on tumor cells were increased significantly in responders except in one case (n=9), whereas no change was evident in nonresponders except in two cases (n=8). Induced maximum levels of IFN-gamma in responders were significantly higher than those in nonresponders. In contrast, there was no significant difference in the induced TNF-alpha or IL-1 beta levels between the two groups. Two types of cultured tumor cells derived from responder patients were successfully established from the 17 different tumor cells in effusion. We performed an in vitro study using these cultured tumor cells. Treatment of the two cultured tumor cells with recombinant IFN-gamma, but not recombinant TNF-alpha or IL-1 beta, significantly increased their ICAM-1 expression to a clinically detectable level. Direct treatment of the tumor cells with cell-free effusion samples obtained from the same patients 24 hr after the therapy successfully increased ICAM-1 expression and this action was blocked completely only by a pretreatment with anti-IFN-gamma mAb. Our results suggests that in this therapy IFN-gamma plays a crucial role in enhancing ICAM-1 expression by tumor cells and that induced IFN-gamma levels may be a useful marker for evaluation of the therapeutic effect.

In vitro analysis of peritoneal adhesions in peritonitis.

Peritoneal adhesions due to peritonitis make surgery more difficult and may cause complications. Clarifying the formation mechanism of peritoneal adhesions could help identify methods useful for their prevention. We cultured mesothelial monolayers on plates and microcarriers to simulate the parietal and visceral peritoneum, respectively. We then investigated the effects of lipopolysacchride (LPS) and tumor necrosis factor (TNF) on the homologous adhesion of these mesothelial monolayers. There was no adhesion of mesothelial monolayers in the control medium. When monolayers were cultured with endotoxin (LPS), approximately 90% of the microcarriers adhered to the mesothelial microplate. Adhesions occurred at LPS concentrations of 10 ng/ml and increased linearly in a dose-dependent manner. Kinetic studies revealed that the mesothelial adhesion appeared at 12 hr, and that 90% of the microcarriers were adherent after 24 hr. Open intercellular spaces were observed after a 24-hr treatment with LPS. Scanning electron microscopy revealed that the mesothelial cells adhered to the naked glass. LPS also caused increased permeability of the mesothelial monolayer. TNF did not cause any significant adhesion. Through our experiments we were able to develop an in vitro model of peritoneal adhesion using peritoneal mesothelial cell culture. Endotoxin caused an increase in homologous adhesion of peritoneal mesothelial monolayers, which may correspond to the initial stage of peritoneal adhesion formation in peritonitis.

A possible role of TGF-beta in the formation of malignant effusions.

The detailed mechanisms underlying the formation of malignant effusions are incompletely defined. In order to determine whether transforming growth factor-beta (TGF-beta) would contribute to the formation of malignant effusions, we investigated the effect of TGF-beta on the morphology, growth, and permeability of human mesothelial cells, which are thought to serve as a permeability barrier in the pleuroperitoneal cavities. Treatment of the mesothelial cells with a TGF-beta dose ranging from 0.1 to 10 ng/ml for 96 hr induced distinct morphologic changes in the cells. Each cell increased in size as did the volume of the intercellular spaces. TGF-beta also significantly inhibited the growth of mesothelial cells at a concentration ranging from 0.1 to 10 ng/ml. This growth inhibition was blocked completely by the addition of anti-TGF-beta antibody. Treatment of the mesothelial cells with 2.0 ng/ml TGF-beta significantly increased the permeability of a mesothelial cell monolayer as assessed by a FITC-albumin permeability assay. In our clinical analysis using 10 effusion samples obtained from patients with various types of carcinoma cells, considerable level of TGF-beta could be detected by ELISA, ranged from 0.90 to 8.75 ng/ml. Our data suggest that TGF-beta plays an important role in the formation of malignant effusions through structural and functional damage to the mesothelial cells. Malignant effusions may accumulate in the pleuroperitoneal cavity as a result of the mesothelial cell damage caused by this cytokine which is released from disseminated cancer cells.

CEA-mediated homotypic aggregation of human colorectal carcinoma cells in a malignant effusion.

This study was performed to clarify the role of carcinoembryonic antigen (CEA) in the aggregation of colorectal carcinoma (CRC) cells in malignant effusions. We analysed freshly purified CRC cells from one patient, which expressed CEA (98% positive cells) on the surface and formed huge cell aggregates in the patient's ascites. The carcinoma cells expressed Sialyl Lewis A (82%), Sialyl Lewis X (92%) and the beta 1 integrin subunit (78%) but did not express the pair-ligands for these molecules. Cell aggregation was completely inhibited by anti-CEA mAb. The decreased CEA expression induced by phosphatidylinositol-specific phospholipase C (PI-PLC) treatment led to decreased cell aggregation. We also examined the correlation between the degree of cell aggregation and CEA expression using smears of ascites fluid from 27 patients with colorectal cancer. There was a significant correlation between the degree of cell aggregation and CEA expression by CRC cells. The present study provided the first evidence that CEA molecules mediate the homotypic aggregation of CRC cells in malignant effusions.

[Establishment and characterization of a new cell line (KT-COLO-8) derived from a colonic mucinous adenocarcinoma].

We have established a human colonic carcinoma cell line, designated KT-COLO-8, derived from cancerous ascites of a 64-year-old male patient who had mucinous adenocarcinoma of the transverse colon. The cells have been cultured with RPMI-1640 medium supplemented with 10% fetal bovine serum. They grew in vitro free-floating and formed sheet-like clusters as large as 2-3 mm in diameter. Population doubling time for the cells was 48 hours. The chromosome number ranged from 48 to 50. The Q-band analysis revealed abnormal karyotype with three marker chromosomes including 1p-, 4q- and 5q-. The cells produced and released high level of carcinoembryonic antigen (CEA) in the conditioned medium. Percentage of CEA positive cells was 98%. An aggregation assay revealed that 80% of the cells dissociated into single cells aggregated within 30 min. The self aggregation of the cells was completely inhibited only by anti-CEA monoclonal antibody, suggesting that the cluster formation of KT-COLO-8 cells was dependent on CEA molecules.

OK-432-induced enhancement of ICAM-1 expression on tumor cells positively correlates to therapeutic effects for malignant effusion.

The intracavitary injection of OK-432 has been shown to be an effective immunotherapy for patients with malignant effusion. We investigated the contribution of intercellular adhesion molecule-1 (ICAM-1) on the surface of tumor cells to its therapeutic effect. We treated 13 patients with malignant effusion with OK-432. Tumor cells were freshly isolated from effusion samples obtained before and 24 hr after initiation of the therapy. Surface expression of ICAM-1 was analyzed by flow cytometry and its relation to the therapeutic effect was analyzed. An objective clinical response was observed in 7 (53.8%) of 13 patients. Following OK-432 injection, ICAM-1 levels showed an average of 5.73-fold increase in clinical responders (7 patients), whereas no increase in nonresponders (6 patients). ICAM-1 expression more than doubled after therapy in 7 patients, 6 of whom showed a clinical response. Survival was significantly prolonged in these patients compared with that in the 6 patients in whom ICAM-1 levels did not double after therapy. Only 1 of the 6 patients in whom ICAM-1 levels did not double showed a clinical response. Pretherapeutic ICAM-1 expression was not significantly correlated with the subsequent clinical effect. OK-432 injection was associated with an increase in surface expression of ICAM-1 on tumor cells. This increased ICAM-1 expression was positively correlated with therapeutic effect, suggesting that ICAM-1 expression on tumor cells may be a useful marker for evaluation of efficacy of OK-432 therapy.

An adult case of bleeding Meckel's diverticulum diagnosed by preoperative angiography.

A 19-year-old woman in her 6th month of pregnancy was admitted to our hospital after passing a massive bloody stool. Romanoscopy and upper gastrointestinal panendoscopy revealed no abnormality, but a superior mesenteric arteriography demonstrated an embryonic artery with the extravasation of contrast medium in the distal end of the ileal artery. After the diagnosis of a bleeding Meckel's diverticulum had been established, an emergency operation was successfully performed. At laparotomy, a Meckel's diverticulum was found, about 70 cm toward the oral side from the ileocecal valve, and part of the ileum, including the diverticulum, was resected. Histological examination indicated that the diverticulum had a normal ileal layer with ectopic gastric mucosa and pancreatic tissue. Furthermore, multiple ulcers were observed in the adjacent ileum. Blood coagulation was observed at the site of one of these ulcers, and this was presumed to be the source of the hemorrhage.

Suppression by interferon-gamma of tumor cell-induced increase in mesothelial permeability.

The effect of interferon-gamma (IFN-gamma) on the interaction between tumor cells and mesothelial cell layers was studied from the aspect of changes in mesothelial permeability. Mesothelial permeability was assessed as the percentage diffusion of radiolabeled albumin across the mesothelial cell sheets on Matrigel-coated filter cup assemblies. When lined gastric carcinoma cells (KATO-III) were seeded on the confluent mesothelial cell layers, the fine cobblestone appearance of the cell sheet was disrupted and mesothelial permeability significantly increased. The increase in permeability was suppressed by the addition of as little as 1 U/ml of IFN-gamma. The effect of IFN-gamma was observed when either the conditioned medium of tumor cells alone or the IFN-gamma-resistant tumor cells, K-562, was placed onto the mesothelium. The cobblestone appearance of the cell sheet was relatively well preserved in the presence of IFN-gamma. In contrast, IFN-alpha did not suppress tumor-induced mesothelial permeability. These results suggest that IFN-gamma has the potential to protect the human mesothelial cell layers against tumor cells.

Intraperitoneal hemorrhage from hepatocellular carcinoma: emergency chemoembolization or embolization.

From 1982 to 1990, 38 patients with intraperitoneal hemorrhage from hepatocellular carcinoma (HCC) underwent treatment with emergency embolization with or without anticancer drug and iodized oil. Before emergency embolization, 24 patients had a serum total bilirubin value of 3.0 mg/dL or less (group A) and 14 patients had hyperbilirubinemia, with a serum bilirubin level greater than 3.0 mg/dL (group B). Successful hemostasis was achieved in all patients. The mean length of survival was 165 days in group A and 13 days in group B. A significant correlation (P less than .00003) between serum bilirubin level and prognosis was obtained. While tumor thrombus in the portal vein made the prognosis poor, there was no significant difference in prognosis between groups with and without tumor thrombus (P = .145). Emergency embolization is an effective treatment in patients with intraperitoneal hemorrhage from HCC. The prognosis for patients with HCC depends on the serum bilirubin level before embolization.

Hiatal herniation of the colon with digestive tract bleeding--a case report.

A 71 year old woman with hiatal herniation was admitted to our hospital with anemia and melena. A barium enema revealed hiatal herniation of the transverse colon in conjunction with the stomach, which seemed to be strangulated by the esophageal hiatus. She underwent surgery, for which Hill's gastropexy method was employed and has had no signs of bleeding since. By presenting this case, we stress the importance of marking a careful differential diagnosis due to the variability in symptoms of digestive tract bleeding.