The relationship between GDNF and integrins in human colorectal cancer cell activity

BACKGROUND/AIMS

This study was performed to determine whether GDNF influences the expression of integrins in colorectal cancer cell lines and to elucidate the mechanisms of adhesion to and invasion of extracellular matrix (ECM) proteins.

METHODOLOGY

The expression of integrin subunits and alteration of this expression by GDNF were examined by flow-cytometric analysis and cellular enzyme-linked immunosorbent assay in four human colorectal cancer cell lines. Assays to evaluate adhesion and invasion of cancer cells toward ECM proteins were conducted to investigate whether increased integrin expression affects the interaction between cancer cells and putative integrin ECM ligands.

RESULTS

The RET/GFRalpha-1 receptor complex for GDNF was expressed in all four colorectal cancer cell lines. The expression of the Beta1 integrin subunit in these cells was significantly enhanced by GDNF. The enhancement and associated increase in adhesion and invasion abilities in response to by GDNF were inhibited by blocking the GDNF receptor or the integrin P1 subunit.

CONCLUSIONS

In colorectal cancer, the enhancement of integrin expression by signaling through the GDNF receptor strongly influences adhesion to and invasion of ECM proteins.

Gastrointestinal stromal tumor of the rectum with liver metastasis: report of a case

Gastrointestinal stromal tumors (GISTs) have unique immunohistochemical and molecular genetic features that set them apart from leiomyomas, leiomyosarcomas, and schwannomas. Although recurrence of GIST usually tends to develop locally or in the liver, rectal GIST reoccur predominantly at the original site of the tumor. We describe a rare case of rectal GIST with multiple liver metastases. We carried out immunohistochemical staining for p53 protein, proliferating cell nuclear antigen (PCNA), integrins, and interleukin-1 receptor type I (IL-1RI) in order to investigate the degree of malignancy of this neoplasm in addition to the immunohistochemical analyses that were necessary for diagnosing GIST. Histologically, the rectal tumor was classified as an uncommitted type of rectal GIST with multiple liver metastases. Positive immunostaining for PCNA, alpha6 integrin subunit, and IL-1RI was found in both the rectal and hepatic tumors. The patients with a rectal GIST may have an increased risk of liver metastasis and a poor prognosis independent of the size of the tumor.

Vascular endothelial growth factor-C secreted by pancreatic cancer cell line promotes lymphatic endothelial cell migration in an in vitro model of tumor lymphangiogenesis

OBJECTIVES

To investigate mechanisms underlying lymphatic node metastasis in pancreatic cancer, we examined roles of vascular endothelial growth factor-C (VEGF-C) in tumor lymphangiogenesis.

METHODS

We measured VEGF-C secretion by pancreatic cancer cell lines using enzyme-linked immunosorbent assay and examined effects of different cell lines on lymphatic endothelial cells (LECs) in vitro.

RESULTS

We identified VEGF-C high-secretion (MIA PaCa-2) and low-secretion cell lines (BxPC-3). The trend of enhancement of LEC proliferation by recombinant human VEGF-C (rVEGF-C) was not statistically significant. Numbers of migrating cells were increased by rVEGF-C treatment in a dose-dependent manner. The MIA PaCa-2 cell culture supernatant caused greater LEC migration than the BxPC-3 supernatant. The VEGF-C effects were significantly inhibited by rVEGF receptor 3 (rVEGF R3)/Fc chimera. In LEC/fibroblast coculture on collagen gel, LEC capillary formation was significantly enhanced by coculture with MIA PaCa-2 cells compared with BxPC-3 cells. Enhanced capillary formation with MIA PaCa-2 cells was inhibited by rVEGF R3/Fc chimera, implying VEGF-C involvement in progression of LEC sprouting in a tumor microenvironment.

CONCLUSIONS

Because VEGF-C secreted by pancreatic cancer cells plays an important role in LEC migration in pancreatic cancer lymphangiogenesis, it is possible that rVEGF R3/Fc chimera might have a role in controlling lymph node metastasis.

A new technique for intestinal isoperistaltic anastomosis utilizing a linear stapler for enlargement after anastomosis performed with a circular stapler

BACKGROUND

The high incidence of anastomotic stenosis after gastrointestinal surgery using circular staplers is a major problem. In response, we have developed a new technique that uses a linear stapler to enlarge an anastomotic opening made using a circular stapler.

METHODS

Anastomoses were created by the new technique or by the conventional approach using a circular stapler in pig small intestine. The method was also applied in treatment of a colon cancer patient.

RESULTS

The area of the anastomotic opening obtained with the new technique was more than 3 times that in the control (p < 0.001), with no significant difference between the methods in a leak test. Follow-up of the patient undergoing surgery with this approach revealed an uneventful course with a widely patent anastomosis confirmed after 3 months.

CONCLUSIONS

This procedure provides a larger anastomotic opening than conventional anastomosis with circular staplers, without impairing the integrity of the anastomosis.

Nuclear-matter modification of decay widths in the phi-->e+e- and phi-->K+K- channels

The invariant mass spectra of phi-->K+K- are measured in 12 GeV p+A reactions in order to search for the in-medium modification of phi mesons. The observed K+K- spectra are well reproduced by the relativistic Breit-Wigner function with a combinatorial background shape in three betagamma regions between 1.0 and 3.5. The nuclear mass number dependence of the yields of the K+K- decay channel is compared to the simultaneously measured e+e- decay channel for carbon and copper targets. We parameterize the production yields as sigma(A)=sigma0Aalpha and obtain alphaphi-->K+K- -alphaphi-->e+e- to be 0.14+/-0.12. Limits are obtained for the partial decay widths of the phi mesons in nuclear matter.

Limiting vein puncture to three needle passes in subclavian vein catheterization by the infraclavicular approach

PURPOSE

With central venous catheterization, each additional vein puncture raises the risk of complications. We assessed the rate of failure and complications using a limiting rule whereby the number of needle passes for subclavian vein catheterization was restricted to three.

METHODS

A prospective clinical trial was conducted between September 2001 and December 2003 in a university hospital surgical department. Two hundred and thirty-two adult patients were enrolled to undergo subclavian vein catheterization under non-emergency conditions. The patients were subjected to right subclavian vein catheterization by the infraclavicular approach. Vein puncture failure was defined as such if venipuncture was not accomplished after three attempts. Any arterial puncture was judged to be a failure immediately.

RESULTS

Vein puncture failure occurred in nine patients (3.9%), and included two arterial punctures (0.9%). No other complications, such as pneumothorax, hemothorax, plexus lesion, mediastinal hematoma or bleeding, or air embolism, were observed. In multivariate analyses, a close to average body mass index (weight in kilograms divided by the square of the height in meters, odds ratio 0.74; 95% confidence interval 0.56-0.97; P = 0.028) was associated with a low risk of failure.

CONCLUSION

Limiting the number of needle passes to three may therefore prevent mechanical complications. A low body mass index was predictive of vein puncture failure.

Expression of alpha6 integrin subunit is associated with malignancy in gastric gastrointestinal stromal tumors

BACKGROUND

Gastrointestinal stromal tumors (GISTs) are the most common non-epithelial neoplasms of the gastrointestinal tract. The aim of this study was to investigate the clinicopathological and immunohistochemical features of gastric GISTs and to evaluate the degree of integrin expression in order to determine the need for surgery or predict the prognosis for GIST patients.

MATERIAL/METHODS

Clinicopathological findings were obtained from patients' records. Specimens from 32 cases of gastric GIST were analyzed with immunohistochemical methods. The c-kit negative examples among the original 48 patients with gastric submucosal and muscle layer tumors were excluded from the study.

RESULTS

There was a significant correlation between p53 protein expression and tumor malignancy. The positive staining for proliferating cell nuclear antigen was observed in all patients, and the mean tumor proliferation index for benign and malignant groups were 3.0% and 16.3%, respectively. alpha5beta1 integrin and alpha6 integrin subunit were expressed from moderately to strongly in tumor cells, and alpha 6 integrin subunit expression correlated significantly with whether tumors were classified as benign or malignant. However, there were no significant differences between the survival of GIST patients and integrin expression, mitotic rate, tumor size, or tumor malignancy.

CONCLUSIONS

Malignant GISTs show significant expression of alpha6 integrin subunit. It may be useful in supporting other parameters, such as p53, MI, and tumor size. We suggest that alpha6 integrin subunit expression may be useful as an indication for surgery and also as one of several prognostic factors.

Evidence for in-medium modification of the phi meson at normal nuclear density

Invariant mass spectra of e(+) e(-) pairs have been measured in 12 GeV p + A reactions to detect possible in-medium modification of vector mesons. Copper and carbon targets are used to study the nuclear-size dependence of e(+) e(-) invariant mass distributions. A significant excess on the low-mass side of the phi meson peak is observed in the low betagamma(= beta/square root(1-beta(2))) region of phi mesons (betagamma < 1.25) with copper targets. However, in the high betagamma region (betagamma > 1.25), spectral shapes of phi mesons are well described by the Breit-Wigner shape when experimental effects are considered. Thus, in addition to our earlier publications on rho/omega modification, this study has experimentally verified vector meson mass modification at normal nuclear density.

294 IN VITRO DEVELOPMENT OF RAT OOCYTES FOLLOWING MICROINJECTION OF A CUMULUS CELL INTO THE OOPLASM AND CHEMICAL ACTIVATION

If diploid zygotes constituted with a somatic and a maternal genome could successfully develop to term, a new reproductive method would be developed to produce animals. However, there appears to be little information on this subject. In the present study, in vitro early development of the constituted zygotes was examined. A cumulus cell was microinjected into a rat non-enucleated oocyte, the reconstructed oocyte was chemically activated, and the pronuclear formation and in vitro development of the embryo was observed. Prepubertal Wistar female rats (21–27 days old) were induced to superovulate with an IP injection of 15 IU of eCG, followed by 15 IU of hCG 48 h later. Cumulus cells were removed from oocytes by pipetting with 0.1% hyaluronidase. Experiment 1: The DNA content of cumulus cells for microinjection was evaluated by flow cytometry. Experiment 2: The optimal concentration of SrCl2 for activation of rat oocytes was examined. Experiment 3: Cumulus cells were injected into mature oocytes in BSA-free HEPES-buffered mKRB containing 0.1% polyvinyl alcohol (PVA) and cytochalasin B (5 �g mL-1), and were then chemically activated by treatment in Ca2+-free mKRB containing 5 mM SrCl2 for 20 min at 0 to 0.5 (A), 1 to 1.5 (B), or 3 to 3.5 h (C) after injection. Activated embryos were cultured in droplets of mKRB in an atmosphere of 5% CO2 in air at 37�C for 9 to 12 h. After being observed for pronuclear formation, the embryos were transferred into mR1ECM-PVA, and the cleavage and blastocyst formation rates were examined 24 and 120 h later, respectively. Results from 3 to 7 replicates were analyzed by ANOVA and Duncan's multiple range test. A total of 90.0 and 9.5% of cumulus cells derived from ovulated oocyte–cumulus complexes contained 2C and 4C DNA contents, respectively. Survival rates did not differ among oocytes stimulated with 0 to 5 mM SrCl2 (96.7–100%) but did differ between those stimulated with 1.25 and 10 mM SrCl2 (100 and 72.9%, respectively). Activation rates of oocytes increased at higher SrCl2 concentrations and were higher at 5 and 10 mM (92.6 and 98.5%, respectively) than at other concentrations. When cumulus-injected oocytes were activated after various periods after the injection, the incidences of pronuclear formation and cleavage did not differ among the periods (A: 95.0 and 81.3%; B: 85.6 and 85.0%; and C: 82.7 and 84.6%, respectively). Although a majority of the embryos developed to the 2- to 4-cell stages (78.7%; 152/208), the blastocyst formation rate was very low (0.8%; 2/208). In conclusion, rat non-enucleated oocytes injected with a cumulus cell can form pronuclei and cleave following chemical activation, but blastocyst formation of the embryos is very limited.

340 EFFECT OF GLUCOSE ON THE MORPHOLOGY OF GERMINAL VESICLE AND MEIOTIC PROGRESSION OF PORCINE OOCYTES IN A CHEMICALLY DEFINED MEDIUM

Glucose metabolism through the pentose phosphate pathway (PPP) seems to play a critical role in meiotic resumption in mouse oocytes (Downs et al. 1998 Biol. Reprod. 58, 1084–1094). However, the role is not clear in porcine oocytes. In the present study, we examined whether glucose affects morphological change of germinal vesicles and the resumption of meiosis in porcine oocytes in a chemically defined medium. In the first experiment, porcine cumulus–oocyte complexes (COCs) were collected from 3–6-mm follicles of slaughterhouse ovaries and cultured in a chemically defined medium, mNCSU37-PVA with/without 5.55 mM glucose in the presence of eCG, hCG, and dibutyryl cAMP for 20–22 h and then in the absence of eCG, hCG, and dibutyryl cAMP for 24 h. In the second experiment, 5.55 mM glucose in the maturation medium was replaced with the same concentration of Na pyruvate. In the third experiment, the PPP inhibitor 6-aminonicotinamide (6-AN) was added to the maturation medium at various concentrations (0, 10, 50, and 100 �M). To determine the activity of glucose-6-phosphate dehydrogenase (G6PD), OCCs were fixed, blocked, and treated with anti-G6PD polyclonal antibody and the secondary antibody labeling a fluorescent material. Results from 3–5 replicates were analyzed by ANOVA and Duncan&apos;s multiple range test. When OCCs were cultured in glucose-free chemically defined maturation media, regardless of the presence of hormones and dibutyryl cAMP, germinal vesicle breakdown (GVBD) of oocytes was inhibited (10.0&ndash;21.3&percnt;), as compared with OCCs cultured in the presence of glucose and hormones (91.4&ndash;92.0&percnt;). In a majority of oocytes in which GVBD was inhibited, the arrest occurred at the GV-I stage. When OCCs were cultured in maturation media in which glucose was replaced with Na pyruvate, GVBD was not inhibited any more than in control samples that were cultured in the presence of glucose (97.4&percnt; vs. 97.1&percnt;). However, the incidence of oocytes developing to the metaphase II stage was significantly lower in this condition than in controls (4.8&percnt; vs. 49.9&percnt;, respectively). A majority of the oocytes were at the metaphase I stage (86.0&percnt; vs. 45.5&percnt; in controls). The presence of 6-AN in maturation media significantly inhibited GVBD of oocytes (77.3, 29.0, 7.4, and 8.4&percnt; at 0, 10, 50, and 100 &micro;M, respectively) and arrested the oocytes at the GV-I stage. Immunocytochemistry with anti-G6PD demonstrated the activity of G6PD in cumulus cells of OCCs. In conclusion, these results demonstrate that glucose plays a critical role in the release of porcine oocytes arrested at the GV-I stage, probably through PPP of cumulus cells. The current results also suggest the possibility of gluconeogenesis in porcine OCCs when glucose in maturation media was replaced with Na pyruvate.

343 DISTRIBUTION OF GLUCOSE-6-PHOSPHATE DEHYDROGENASE AND IN VITRO MATURATION OF PORCINE OOCYTE - CUMULUS COMPLEXES FROM SMALL AND MEDIUM FOLLICLES

Glucose metabolism through the pentose phosphate pathway (PPP) plays a critical role in meiotic maturation and fertilization. However, the relationship between the distribution of a PPP key enzyme, glucose-6-phosphate dehydrogenase (G6PD), in cumulus–oocyte complexes (COCs) and the in vitro maturation (IVM) of the oocytes is not clear. In the present study, we examined the distribution of G6PD, the morphological characteristics in OCCs derived from small (d2 mm in diameter) and medium (3 to 6 mm in diameter) follicles, and the rate of oocyte maturation. Porcine COCs were collected from small or medium follicles of slaughterhouse ovaries. The COCs were cultured in a maturation medium, BSA-free NCSU37 supplemented with 10% porcine follicular fluid, eCG, and hCG, for 20 h and then in the absence of hormones for 24 h. To determine the distribution of G6PD, the COCs were treated with 13 �M brilliant cresyl blue (BCB) in TL-HEPES-PVA for 90 min. Results from 3–6 replicates were analyzed by ANOVA and Duncan&apos;s multiple range test. The mean diameters for COCs collected from small follicles (136.7 &micro;m for the outer zona and 103.1 &micro;m for ooplasm) were significantly less than for those derived from medium follicles (164.1 &micro;m and 122.0 &micro;m, respectively). G6PD activity was detected in the cumulus cells for most of the COCs derived from medium follicles, but it was not significantly different from that of COCs derived from small follicles. In the second group of COCs, very little G6PD activity was found in both the cumulus cells and the oocytes (34.7 &plusmn; 11.5&percnt; and 18.0 &plusmn; 6.7&percnt; in COCS derived from small and medium follicles, respectively). After stimulation by eCG and hCG, the percentages of COCS in which G6PD activity was detected in the cumulus cells, but not in the oocytes, were 56.2 &plusmn; 23.8&percnt; and 72.9 &plusmn; 6.1&percnt; for small and medium follicles, respectively. The percentage of oocytes at the metaphase II stage (53&percnt; and 63.9&percnt; in oocytes from small and medium follicles, respectively) was higher for the COCs that showed higher G6PD activity in their cumulus cells. In conclusion, although no statistical differences were detected in the distribution of G6PD between COCs from small and medium follicles, due to a large variation, a higher percentage of mature oocytes seems to be the result of COCs where the G6PD activity is detected in the cumulus cells, but not in the oocyte, during IVM.

The stem cell factor/c-kit receptor pathway enhances proliferation and invasion of pancreatic cancer cells

BACKGROUND

The transmembrane protein c-kit is a receptor tyrosine kinase (KIT) and KIT is expressed in solid tumors and hematological malignancies such as gastrointestinal stromal tumor (GIST), small-cell lung cancer and chronic myelogenous leukemia (CML). KIT plays a critical role in cell proliferation and differentiation and represents a logical therapeutic target in GIST and CML. In pancreatic cancer, c-kit expression has been observed by immunohistochemical techniques. In this study, we examined the influence of c-kit expression on proliferation and invasion using five pancreatic cancer cell lines. In addition, the inhibitory effect of imatinib mesylate on stem cell factor (SCF)-induced proliferation and invasion was evaluated. Finally, we also analyzed KIT and SCF expression in pancreatic cancer tissues using immunohistochemistry and correlated the results with clinical features.

RESULTS

RT-PCR revealed that two pancreatic cancer cell lines, PANC-1 and SW1990, expressed c-kit mRNA. By Western blot analysis, c-kit protein was also present in those lines. In KIT-positive pancreatic cancer cell lines, proliferation and invasion were significantly enhanced by addition of SCF. In contrast, SCF did not enhance proliferation and invasion in the three KIT-negative lines (BxPC-3, Capan-2 and MIA PaCa-2). 5 muM imatinib mesylate significantly inhibited SCF-enhanced proliferation to the same extent compared with the control. Similarly, SCF-enhanced invasive ability was significantly inhibited by 5 muM imatinib mesylate. KIT was expressed in 16 of 42 clinical specimens by immunohistochemistry, and KIT expression was significantly related to venous system invasion. Furthermore, patients expressing both KIT and SCF had a somewhat lower survival.

CONCLUSION

Our results demonstrated that the SCF-KIT pathway enhanced the proliferation and invasiveness in KIT-positive pancreatic cancer cell lines and that the enhanced proliferation and invasion were inhibited by imatinib mesylate. We propose that inhibitors of c-kit tyrosine kinase receptor have the potential to slow the progression of KIT-positive pancreatic cancers.

Malignant solitary fibrous tumor originating from the peritoneum and review of the literature

BACKGROUND

Solitary fibrous tumor (SFT) is a rare neoplasm frequently involving the pleura. Benign and malignant forms of the tumor occur, the benign variant being three to four times more common than the malignant.

CASE REPORT

We present herein a rare case of large malignant solitary fibrous tumor (SFT) originating from the peritoneum. An abdominal computed tomography scan revealed a well-defined solid tumor with mixed density. An abdominal ultrasonography (US) revealed a well-circumscribed solid tumor containing a partially cystic lesion. T1-weighted abdominal magnetic resonance imaging demonstrated a hypo- to isointensity, which was a hypo- to hyperintensity on T2-weighted images. Liposarcoma originating from the retroperitoneum was suggested, and the patient underwent a complete resection of the tumor as well as the left kidney because tumor invasion of the upper left kidney was suspected. Immunohistochemically, the spindle-shaped cells were positive for CD34, and the diagnosis was SFT originating from the peritoneum. At the 14-month follow-up evaluation, no recurrence or metastasis was detected.

CONCLUSIONS

This case gave us some difficulty, and the correct diagnosis of the peritoneal mass was valuable. To diagnose the malignant potential of this type of tumor accurately may have value to direct the appropriate therapeutic operations after surgery and postoperative progress observation.

Reactive lymphoid hyperplasia of the liver in a patient with colon cancer: report of two cases

BACKGROUND

Reactive lymphoid hyperplasia (RLH) of the liver is very rarely reported, and we encountered two cases of RLH of the liver in a patient with colon cancer.

CASE PRESENTATION

In the first case, a 77-year-old woman was admitted for the surgical removal of a ascending colon cancer. A hepatic tumor in the left lobe was concurrently revealed by computed tomography (CT), and magnetic resonance imaging (MRI). The appearance suggested liver metastasis. Right hemicolectomy and partial hepatectomy were performed. On histopathological examination, lymphoid follicles with germinal centers were seen in the tumor-like lesion, and remarkable lymphoid infiltration with germinal centers was seen in the portal area around the nodule. Immunohistochemical studies revealed polyclonality of infiltrating lymphocyte. Consequently, this nodular lesion was diagnosed as RLH of the liver. In the second case, a 64-year-old woman who had a radical right hemicolectomy for stage II ascending colon cancer 10 years ago was admitted with dysuria. A hepatic tumor in the left lobe was concurrently revealed by CT and MRI, suggesting hepatocellular carcinoma. A left lateral segmentectomy was performed. Microscopically, this lesion revealed the almost same findings as the first case, so this nodular lesion was diagnosed as RLH of the liver.

CONCLUSION

Our two cases were the first report of RLH of the liver accompanying colon cancer. Because there are a very few cases, so it is not clear whether the malignancies were involved in the onset of RLH. But we believe that new factors involved in the onset mechanism of RLH may be identified by carefully monitoring the clinical course of our two patients.

Clinicopathologic study of intraductal papillary-mucinous tumors and mucinous cystic tumors of the pancreas

BACKGROUND/AIMS

We analyzed clinicopathologic and imaging findings of intraductal papillary-mucinous tumors (IPMTs) and mucinous cystic tumors (MCTs) of the pancreas to evaluate the difference between IPMTs and MCTs, and to identify the signs indicative of malignancy in IPMTs.

METHODOLOGY

Clinicopathological features of 20 patients with IPMT and six patients with MCT of the pancreas were studied.

RESULTS

The patients with IPMT comprised 16 males and four females with a mean age of 62.9 years. Eighty percent of IPMTs were located in the pancreatic head, and the mean tumor size was 38.6mm. Recurrence was observed in one patient, who died of IPM adenocarcinoma. In contrast, all patients with MCT were females, with a mean age of 53.0 years. None of the MCTs arose in the pancreatic head, and the mean tumor size was 42.7mm. One patient died of MC adenocarcinoma, but all of the others survived without recurrence. The difference in gender, location of the tumor, and connection to the pancreatic duct reached statistical significance between IPMTs and MCTs. A significant connection to the pancreatic duct and high level of serum carbohydrate antigen 19-9 (CA19-9) was observed in the adenocarcinoma and moderate dysplasia groups of IPMT.

CONCLUSIONS

The main duct type and an elevation of serum CA19-9 level suggested malignancy in IPMTs.

Surgical treatment for relief of severe pain with chronic pancreatitis that is resistant to conservative treatment

BACKGROUND/AIMS

To evaluate the surgical treatment, we investigated that performed for chronic pancreatitis patients suffering from severe pain resistant to conservative treatments.

METHODOLOGY

Nineteen chronic pancreatitis patients with severe pain resistant for a long time to previous conservative medical and/or interventional treatments underwent surgery retrospectively. We evaluated a difference of postoperative improvement of symptoms in patients with surgical treatment including nerve plexus resection.

RESULTS

The mean follow-up interval after surgery was 59.7 months (range, 3.0-187.3 months). Of 19 patients, 14 (73.7%) underwent nerve plexus resection. Relief of symptoms was observed in 16 of 19 patients (84.2%). Fourteen of the 15 patients (93.3%) in the nerve plexus resection group were relieved of symptoms after surgery, compared to only two of four (50.0%) patients in the nerve plexus non-resection group.

CONCLUSIONS

Surgical treatments with nerve plexus resection appropriately matched with individual patients are very safe and contribute to the improvement of the quality of life for chronic pancreatitis patients resistant to conservative treatments.

A new method for constructing an ileal J pouch without an enterotomy

The conventional methods of making an ileal J pouch require an enterotomy to introduce a linear stapler. We devised a new surgical technique that removes any need for this enterotomy by using both circular and linear staplers. We applied this method to two patients who underwent a total colectomy for ulcerative colitis and succeeded in making a J pouch without difficulty. This procedure may represent an improved method of making a J pouch.

Regulation by orexin of feeding behaviour and locomotor activity in the goldfish

Orexin is a hypothalamic neuropeptide that is implicated in the regulation of feeding behaviour and the sleep-wakefulness cycle in mammals. However, in spite of a growing body of knowledge concerning orexin in mammals, the orexin system and its function have not been well studied in lower vertebrates. In the present study, we first examined the effect of feeding status on the orexin-like immunoreactivity (orexin-LI) and the expression of orexin mRNA in the goldfish brain. The number of cells showing orexin-LI in the hypothalamus of goldfish brain showed a significant increase in fasted fish and a significant decrease in glucose-injected fish. The expression level of orexin mRNA in the brains of fasted fish increased compared to that of fed fish. We also examined the effect of an i.c.v. injection of orexin or an anti-orexin serum on food intake and locomotor activity in the goldfish. Administration of orexin by i.c.v. injection induced a significant increase of food intake and locomotor activity, whereas i.p. injection of glucose or i.c.v. injection of anti-orexin serum decreased food consumption. These results indicate that the orexin functions as an orexigenic factor in the goldfish brain.

Experimental signature of medium modifications for rho and omega mesons in the 12 GeV p+A reactions

The invariant mass spectra of e+e- pairs produced in 12 GeV proton-induced nuclear reactions are measured at the KEK Proton Synchrotron. On the low-mass side of the meson peak, a significant enhancement over the known hadronic sources has been observed. The mass spectra, including the excess, are well reproduced by a model that takes into account the density dependence of the vector meson mass modification, as theoretically predicted.

Clinicopathological and immunohistochemical analysis of malignant features in mucinous cystic tumors of the pancreas

BACKGROUND/AIMS

To investigate the malignancy of mucinous cystic tumors (MCTs) of the pancreas, we examined clinicopathological features and immunohistochemical findings of MCT.

METHODOLOGY

We analyzed the expression of p53 protein, proliferating cell nuclear antigen, alpha6-integrin subunit, alpha5beta1-integrin, and interleukin-1 receptor type I in tumor specimens from eight patients with MCT.

RESULTS

The tumors were classified as mucinous cyst adenoma (n=6) or mucinous cyst adenocarcinoma (n=2). The actuarial five-year survival rate was 83.3%. All in eight MCTs had 'ovarian-type' stroma in the cyst wall. The alpha6-integrin subunit and p53 protein were expressed in adenocarcinoma tissues of MCTs, and in two adenomas the alpha6-integrin subunit and p53 protein were also co-expressed.

CONCLUSIONS

Our present results indicate that coexpression of the alpha6-integrin subunit and p53 protein should be appreciated as an indicator of malignancy in MCTs.

Interleukin-1alpha enhances the aggressive behavior of pancreatic cancer cells by regulating the alpha6beta1-integrin and urokinase plasminogen activator receptor expression

Background

In human pancreatic cancer progression, the α₆β₁-integrin is expressed on cancer cell surface during invasion and metastasis formation. In this study, we investigated whether interleukin (IL)-1α induces the alterations of integrin subunits and urokinase plasminogen activator/urokinase plasminogen activator receptor (uPA/uPAR) expression in pancreatic cancer cells. We hypothesize that the alterations of integrin subunits and uPA/uPAR expression make an important role in signaling pathways responsible for biological behavior of pancreatic cancer cells.

Results

IL-1α upregulated the expression of α₆ and β₁ integrins without any alterations of α₅ and α_v integrins expression. IL-1α also induced enhancement in the expression of uPA/uPAR in pancreatic cancer cells. IL-1α enhanced the proliferation, adhesion, and migration in pancreatic cancer cells, and IL-1α-induced alterations of uPA/uPAR expression correlated with the increased the migration of pancreatic cancer cells. Upregulation of α₆ integrin subunit and uPA/uPAR correlated with the activation of Ras and downstream extracellular signal-regulated kinase (ERK) pathways. IL-1α-induced activation of Ras and downstream ERK can be inhibited by using inhibitory antibodies against α₆ and β₁ integrin and uPAR, consistent with the inhibition of proliferation, adhesion and migration of pancreatic cancer cells. Immunohistochemical analysis demonstrated a significant association between strong expressions of α₆ integrin with uPAR in pancreatic cancer specimens. Furthermore, the strong expression of α₆ integrin and uPAR was found to be independent prognosticator in pancreatic cancer patients.

Conclusion

Based on these findings, we conclude that IL-1α can induce selective upregulation of α₆β₁-integrin and uPA/uPAR in pancreatic cancer cells and these changes may modulate the aggressive functions of pancreatic cancer.

Integrin-linked kinase activity is associated with interleukin-1α-induced progressive behavior of pancreatic cancer and poor patient survival

Cancer cell adhesion and invasion into extracellular matrix are regulated by integrin-linked kinase (ILK) activity in a phosphatidylinositol 3-kinase (PI3-K)-dependent manner. In this study, we demonstrated that ILK and beta(1)-integrin play important roles in interleukin (IL)-1alpha-induced enhancement of adhesion and invasion of pancreatic cancer cells through p38 mitogen-activated protein kinase (MAPK) signaling pathway and activator protein-1 (AP-1) activation. Alteration of ILK kinase activity controlled IL-1alpha-induced p38 MAPK phosphorylation and its downstream AP-1 activation with subsequent regulation of pancreatic cancer cell adhesion and invasion. Overexpressed ILK enhances the IL-1alpha-induced p38 MAPK phosphorylation more strongly through glycogen synthase kinase 3 (GSK-3) activation, and subsequently induces AP-1 activation, which promotes aggressive capabilities of pancreatic cancer cells. In contrast, knockdown of ILK kinase activity inhibits the IL-1alpha-induced activation of MAPK/AP-1 pathway via inhibition of GSK-3 phosphorylation. In immunohistochemical analysis, statistically significant association between strong expression of ILK and poor prognosis of pancreatic cancer patients were observed, and strong expression of ILK in cancerous tissues can be a significant prognostic indicator of pancreatic cancer patients. Our results suggest that ILK is involved with aggressive capability in pancreatic cancer and that these regulations can be helpful to understand biological processes for a better translational treatment for pancreatic cancer patients.

Expression of glial cell line-derived neurotrophic factor family members and their receptors in pancreatic cancers

BACKGROUND

The glial cell line-derived neurotrophic factor (GDNF) is a member of neurotrophic polypeptide family, which promotes survival and rescue of various neural cells in the central and peripheral nerve systems. We previously reported that GDNF promotes tumor cell invasion in pancreatic cancer cell lines. The purpose of this study was to investigate GDNF family expression and the status of related receptors in actual cancer tissues, and assess correlations with clinicopathologic behavior.

METHODS

Immunohistochemical assessment of GDNF, neurturin, persephin, artemin, GDNF family receptor alpha-1 and alpha-2, and RET was performed for 51 cases of surgically resected pancreatic cancer.

RESULTS

In all intrapancreatic nerves, GDNF and artermin were expressed strongly. In pancreatic cancer tissues. The expression of RET was stronger than that seen in normal ductal cells and was significantly related to the survival rate after resection (P = .026) and lymphatic invasion (P = .014). Intrapancreatic neural invasion was significantly related to the expression of GDNF (P = .047).

CONCLUSIONS

We conclude that the expression of RET in pancreatic cancer tissues may be a useful prognostic marker and GDNF may play an important role in neural invasion.