Optimal double-spin method for maximizing the concentration of platelets in equine platelet-rich plasma.

This study optimized the double-spin conditions for preparing equine platelet-rich plasma (PRP): leukocyte-rich PRP (L-PRP) and leukocyte-poor PRP (P-PRP). Whole blood samples were centrifuged at various double-spin conditions. Both L-PRP and P-PRP were prepared at each stage, and complete blood counts and growth factor concentrations were compared. Samples centrifuged at 160 × 900 g, 160 × 2,000 g, and 400 × 2,000 g exhibited the highest platelet counts. P-PRP had significantly lower leukocyte and erythrocyte contents than L-PRP, especially at 400 × 2,000 g. No significant differences were observed in growth factor concentrations. Our data suggest that optimum L-PRP preparation should include centrifugation under the aforementioned conditions, whereas centrifugation at 400 × 2,000 g is optimal for P-PRP.

Enantioseparation Using Cellulose Tris(3,5-dimethylphenylcarbamate) as Chiral Stationary Phase for HPLC: Influence of Molecular Weight of Cellulose.

The cellulose oligomers with different degrees of polymerization (DP), 7, 11, 18, 24, 26, 40 and 52, were prepared by hydrolysis of microcrystalline cellulose with phosphoric acid. These oligomers including the starting microcrystalline cellulose (DP 124) were converted to tris(3,5-dimethylphenylcarbamate) (CDMPC) derivatives by the reaction with an excess of 3,5-dimethylphenyl isocyanate to be used as the chiral stationary phase (CSP) in high-performance liquid chromatography (HPLC). The structures of the CDMPC derivatives were investigated by infrared spectroscopy (IR), ¹H-NMR, circular dichroism (CD) and size exclusion chromatography (SEC), and the DPs of the derivatives estimated by SEC agreed with those estimated by ¹H-NMR. After coating the derivatives on silica gel, their chiral recognition abilities were evaluated using eight racemates under a normal phase condition with a hexane-2-propanol (99/1) mixture as an eluent. The chiral recognition abilities of 7- and 11-mers, particularly the former, were lower than those of the higher oligomers from DP 18 to 52, which had rather similar abilities to that of 124-mer, although the abilities depended on the racemates. DP 18 seems to be sufficient for CDMPC to exhibit chiral recognition similar to that of the CDMPC with larger DPs.

Naphthalene-based environmentally sensitive fluorescent 8-substituted 2'-deoxyadenosines: application to DNA detection.

We synthesized various C8-naphthylethynylated 2'-deoxyadenosine derivatives and investigated their photophysical properties. Among them, cyano- and N,N-dimethylamino-substituted 8-naphthylethynylated 2'-deoxyadenosine derivatives ((cn)A and (dn)A) showed strong fluorescence with high quantum yields and a remarkable solvatofuorochromicity. In particular, fluorescence of N,N-dimethylamino-substituted (2,6dn)A was not quenched by neighboring guanines (Gs) when incorporated in DNA duplexes, in contrast to (cn)A. We developed a new fluorescent probe containing (2,6dn)A that can be used for the detection of target DNA via a bulge formation regardless of the neighboring sequences.

Carcinoembryonic antigen elevation in post-hepatectomy patients with colorectal cancer liver metastasis indicates recurrence with high accuracy.

BACKGROUND/AIMS: We aimed to retrospectively determine the accuracy of postoperative serum carcinoembryonic antigen (CEA) monitoring to detect or rule out recurrence in post-hepatectomy colorectal cancer patients by using a new statistical technique, likelihood ratio and post-test probability. METHODS: A total of 110 colorectal cancer patients who underwent curative hepatectomy were enrolled. A serum CEA assay and radiological examination were performed routinely for 5 years after surgery or until recurrence was detected. Yearly recurrence rates, sensitivities, specificities, and likelihood ratios were calculated. Post-test probabilities were calculated using these values. RESULTS: All episodes of recurrence occurred within 3 years after hepatectomy. The most frequent recurrence site was the liver, with a recurrence rate of 61.4% of all recurrence. The post-test probabilities of recurrence in post-hepatectomy colorectal cancer patients with positive and negative serum CEA were approximately 70-90% and 10%, respectively. CONCLUSIONS: CEA elevation in colorectal cancer patients who underwent curative resection indicated recurrence with high accuracy because of the high recurrence rate in the liver, in which CEA elevation is more frequent than in other recurrent sites. The elevation of CEA in post-hepatectomy patients necessitates frequent examination using imaging techniques to reveal undetected metastasis as soon as possible.

Relationship between sensory saltiness intensity and added oil in low-viscosity and high-viscosity polymer solutions.

Generally, the foods we usually eat are not only aqueous solutions, but also viscous solutions and solids. Therefore, it is interesting for us to explore how taste components are perceived in a viscous polymer solution. The relationship between the sensory evaluation of saltiness intensity, amount of added oil, and apparent viscosity was clarified in low-viscosity and high-viscosity polymer solutions. The study was conducted using samples containing corn oil, sodium chloride, and [xanthan gum] or [xanthan gum + locust bean gum] as a thickener. Oil was added to the viscous polymer solutions regardless of whether they were low- or high-viscosity, and saltiness intensity was evaluated as compared with a reference solution. The low-viscous polymer solutions with [xanthan gum] were perceived to be saltier than the high-viscous polymer solutions with [xanthan gum + LBG] as the amount of oil increased. The shear stress value gradually increased as the amount of oil increased in both the low-viscosity and the high-viscosity polymer solutions, as derived from the fluid constitutive equation. There was a correlation between saltiness intensity and apparent viscosity in both high- and low-viscosity polymer solutions. A coefficient of determination (R2 ) of 0.918 was obtained between saltiness intensity and "apparent viscosity" for the samples using [xanthan gum] and that of 0.683 between saltiness intensity and "apparent viscosity" for the samples using [xanthan gum+LBG]. The low-viscosity polymer solutions showed a saltier intensity as the amount of oil increased and a greater correlation with apparent viscosity, as compared with the high-viscosity polymer solutions.

Thromboxane A2 and prostaglandin F2alpha mediate inflammatory tachycardia.

Systemic inflammation induces various adaptive responses including tachycardia. Although inflammation-associated tachycardia has been thought to result from increased sympathetic discharge caused by inflammatory signals of the immune system, definitive proof has been lacking. Prostanoids, including prostaglandin (PG) D(2), PGE(2), PGF(2alpha), PGI(2) and thromboxane (TX) A(2), exert their actions through specific receptors: DP, EP (EP(1), EP(2), EP(3), EP(4)), FP, IP and TP, respectively. Here we have examined the roles of prostanoids in inflammatory tachycardia using mice that lack each of these receptors individually. The TXA(2) analog I-BOP and PGF(2alpha) each increased the beating rate of the isolated atrium of wild-type mice in vitro through interaction with TP and FP receptors, respectively. The cytokine-induced increase in beating rate was markedly inhibited in atria from mice lacking either TP or FP receptors. The tachycardia induced in wild-type mice by injection of lipopolysaccharide (LPS) was greatly attenuated in TP-deficient or FP-deficient mice and was completely absent in mice lacking both TP and FP. The beta-blocker propranolol did not block the LPS-induced increase in heart rate in wild-type animals. Our results show that inflammatory tachycardia is caused by a direct action on the heart of TXA(2) and PGF(2alpha) formed under systemic inflammatory conditions.

Precipitation Hardening at Elevated Temperatures above 400 °C and Subsequent Natural Age Hardening of Commercial Al-Si-Cu Alloy.

The precipitation of intermetallic phases and the associated hardening by artificial aging treatments at elevated temperatures above 400 °C were systematically investigated in the commercially available AC2B alloy with a nominal composition of Al-6Si-3Cu (mass%). The natural age hardening of the artificially aged samples at various temperatures was also examined. A slight increase in hardness (approximately 5 HV) of the AC2B alloy was observed at an elevated temperature of 480 °C. The hardness change is attributed to the precipitation of metastable phases associated with the α-Al15(Fe, Mn)3Si2 phase containing a large amount of impurity elements (Fe and Mn). At a lower temperature of 400 °C, a slight artificial-age hardening appeared. Subsequently, the hardness decreased moderately. This phenomenon was attributed to the precipitation of stable θ-Al2Cu and Q-Al4Cu2Mg8Si6 phases and their coarsening after a long duration. The precipitation sequence was rationalized by thermodynamic calculations for the Al-Si-Cu-Fe-Mn-Mg system. The natural age-hardening behavior significantly varied depending on the prior artificial aging temperatures ranging from 400 °C to 500 °C. The natural age-hardening was found to strongly depend on the solute contents of Cu and Si in the Al matrix. This study provides fundamental insights into controlling the strength level of commercial Al-Si-Cu cast alloys with impurity elements using the cooling process after solution treatment at elevated temperatures above 400 °C.

Cancer cell-derived IL-1α promotes HGF secretion by stromal cells and enhances metastatic potential in pancreatic cancer cells.

BACKGROUND AND OBJECTIVES: Interleukin (IL)-1α and hepatocyte growth factor (HGF) play an important role in pancreatic cancer proliferation, angiogenesis, and invasiveness. The aim of this study was to investigate the cooperative role of HGF and IL-1α in metastatic processes promoted by interactions between pancreatic cancer cells and stromal cells. METHODS: Expression of IL-1α and HGF mRNA and protein was determined by RT-PCR and ELISA. The effect of HGF on metastatic potential was evaluated by proliferation, invasion, and angiogenesis assays using an in vitro system consisting of co-cultured tumor cells and stromal cells. RESULTS: IL-1α expression was closely correlated with metastatic potential, and cancer cell-derived IL-1α significantly promoted HGF expression by fibroblasts (P < 0.01). HGF not only enhanced the invasiveness and proliferation of pancreatic cancer cells, but also enhanced migration and proliferation of human umbilical vein endothelial cells (HUVECs). HGF significantly enhanced HUVEC tube formation (P < 0.01). Furthermore, the high liver-metastatic pancreatic cancer cell line (BxPC-3), which secretes IL-1α, significantly enhanced HUVEC tube formation compared with the low liver-metastatic cell line (Capan-2), which does not produce IL-1α (P < 0.01). CONCLUSION: Autocrine IL-1α and paracrine HGF co-enhance the metastatic potential of pancreatic cancer cells via both IL-1α and HGF signaling pathways.

Effect of Helicobacter bilis infection on human bile duct cancer cells.

BACKGROUND: Helicobacter pylori infection is known to be associated with chronic atrophic gastritis, peptic ulcers, and gastric malignancies. However, the effects of other Helicobacter species have not been investigated extensively. In mice, a close relationship is observed between Helicobacter hepaticus and hepatocellular carcinoma, and Helicobacter species can be found in humans, most commonly in extragastric organs. There have also been reports that H. bilis may be associated with biliary malignancies in humans. The effect of H. bilis infection on a human bile duct cancer cell line was investigated in this study. METHODS: We prepared HuCCT-1, the human bile duct cancer cell line, which was cocultured with H. bilis and cultured alone as a control. HuCCT-1 with and without H. bilis were transfected with the NF-kappaB, E2 transcription factor (E2F), and cyclic AMP response element (CRE) luciferase vectors. The activity of NF-kappaB between H. bilis and the infected and noninfected HuCCT-1 cells was also measured by dual luciferase reporter assay. The concentration of vascular endothelial growth factor (VEGF) in the cocultured medium and control medium were measured by ELISA. To investigate the effect of H. bilis infection on HuCCT-1 with regard to human umbilical vein endothelial cell (HUVEC) tube formation, HUVECs and fibroblasts were cocultured in 24-well plates with and without the conditioned medium. RESULTS: NF-kappaB, E2F and CRE activity, production of VEGF, and angiogenesis in H. bilis-infected cell lines were enhanced compared with controls. CONCLUSIONS: H. bilis infection in a human bile duct cancer cell line activates transcript factors such as NF-kappaB that stimulate production of VEGF and lead to enhancement of angiogenesis. H. bilis infection may play an important role in malignancies in the biliary tract.

Quantification of norepinephrine and its metabolites in the plasma of renal failure models.

BACKGROUND/AIMS: The plasma concentration of catecholamines and their metabolites generated by catechol-O-methyl transferase (COMT) were measured and their correlation with the progress of renal dysfunction was investigated in two distinctive animal models: a 5/6 nephrectomized Sprague-Dawley rat model and a 1/2 nephrectomized diabetic fatty Zucker rat model. METHODS: A highly sensitive, high-performance liquid chromatography-peroxyoxalate chemiluminescence reaction detection was employed to obtain values for the ratio [NMN]/([NE] + [NMN]), where [NE] represents the plasma concentration of norepinephrine and [NMN] represents the plasma concentration of normetanephrine. RESULTS: The [NMN]/([NE] + [NMN]) ratio correlated with both the increase in blood urea nitrogen concentration and the decrease in creatinine clearance. CONCLUSION: The [NMN]/([NE] + [NMN]) ratio represents a quantitative indicator of the progress of renal dysfunction in the animal models. Regulation of COMT activity seemed to relate with the progress of renal dysfunction.

Green analytical method for the simultaneous analysis of cytochrome P450 probe substrates by poly(N-isopropylacrylamide)-based temperature-responsive chromatography.

High-performance liquid chromatography (HPLC) is the most common analytical method practiced in various fields and used for analysis of almost all drug compounds in the pharmaceutical industries. During drug development, an evaluation of potential drug interaction with cytochrome P450 (CYP) is essential. A "cocktail" approach is often used in drug development to evaluate the effect of a drug candidate on multiple CYP enzymes in a single experiment. So far, simultaneous analysis of multiple CYP substrates, which have greatly different structure and physicochemical properties, has required organic solvents and mobile phase gradient methods. However, despite the recent emphasis on environmental protection, analytical methods that use only aqueous solvents without the use of organic solvents for separation have not been studied well. This study sought to develop the simultaneous analysis of multiple CYP substrates by using poly(N-isopropylacrylamide) (PNIPAAm)-based temperature-responsive chromatography with only aqueous solvents and isocratic methods. Good separation of multiple CYP substrates was achieved without using organic solvents and any gradient methods by temperature-responsive chromatography utilizing a P(NIPAAm-co-n-butyl methacrylate (BMA))- and P(NIPAAm-co-N-acryloyl L-tryptophan methyl ester (L-Trp-OMe))-grafted silica column. Overall, PNIPAAm-based temperature-responsive chromatography represents a remarkably simple, versatile, and environmentally friendly bioanalytical method for CYP substrates and their metabolites.

Preventive Effects of Repetitive Peripheral Magnetic Stimulation on Muscle Atrophy in the Paretic Lower Limb of Acute Stroke Patients: A Pilot Study.

OBJECTIVE: The aim of this study was to investigate the effect of repetitive peripheral magnetic stimulation (rPMS) on muscle atrophy prevention in the rectus femoris muscle (RF) of the paretic limb in acute stroke patients. METHODS: Twelve acute stroke patients with a National Institute of Health Stroke Scale score >5 and a motor score of the paretic lower limb >2 at admission were divided into an intervention group (rPMS: mean age, 75±6.4 years) and a conventional care group (non-rPMS: mean age, 62±11.8 years). Baseline measurements were performed within 4 days of stroke onset. In the rPMS group, treatment was applied to the paretic thigh only for 2 weeks, 5 days a week, in addition to conventional care. The cross-sectional area (CSA) of the RF was assessed in both limbs using ultrasound at baseline and 2 weeks later. Data on patient characteristics were collected from the clinical records to assess correlations with the CSA rate of change. RESULTS: Patients in the rPMS group were significantly older. Although the CSA of the RF did not change significantly on either side in the rPMS group, there was a significant decrease in the CSA on the paretic side in the non-rPMS group. However, no significant difference was observed in the CSA rate of change in the rPMS and non-rPMS groups. The CSA rate of change on the paretic side correlated negatively with age in the rPMS group. CONCLUSIONS: Our results suggest that rPMS prevents muscle atrophy more effectively in patients in their 60s than in patients more than 70 years old.

Measurements of ligamentum flavum thickening at lumbar spine using MRI.

INTRODUCTION: As the ligamentum flavum (LF) covers most of the posterolateral part of the lumbar spinal canal, its thickening can be attributed to the development of lumbar canal encroachment. Nevertheless, there have been few reports describing the natural history of the LF. METHOD: To investigate the natural history and to subsequently clarify the pathogenesis of LF thickening, we conducted a transverse radiological study of the LF at the lumbar spine using magnetic resonance images. PATIENTS: One hundred and sixty-two patients complaining of low back pain and/or leg pain were evaluated (n = 162; mean age 52.1 years). The thickness of LF was measured at L2-3, L3-4, L4-5 and L5-S levels (n = 648). The relationships among thickness, age, and spinal level were examined. PATIENTS: One hundred and sixty-two patients complaining of low back pain and/or leg pain were evaluated (n = 162; mean age 52.1 years). The thickness of LF was measured at L2-3, L3-4, L4-5 and L5-S levels (n = 648). The relationships among thickness, age, and spinal level were examined. RESULTS: The following results were obtained. (1) LF thickness increased with age; however, the increments at L4-5 and L3-4 were larger than one at L2-3 and L5-S1. (2) At L4-5, LF was over 3.0 mm thick in patients in the 20-29 age bracket, and in many of them it was more than 3.5 mm thick. (3) All patients with a thickened LF at L2-3 (>3.0 mm) had very thick LFs at all spinal levels. (4) In elderly patients, there was no correlation between the thickness of LF and the decrease of the disc height. In this study, we concluded that thickening of LF at L4-5 had already started in patients in the 30-39 age bracket and that thickening of the LF was not the buckling of the LF into the spinal canal with disc degeneration. The thickness of LF at L2-3 may serve as an indicator of lumbar spinal canal stenosis at multiple levels.

Interleukin-1alpha enhances angiogenesis and is associated with liver metastatic potential in human gastric cancer cell lines.

BACKGROUND: To better understand the underlying mechanism of liver metastasis formation in human gastric cancer, we evaluated the angiogenic capabilities of human gastric cancer cell lines with different metastatic potentials as well as the role of interleukin (IL)-1alpha in the angiogenic process. MATERIALS AND METHODS: Reverse transcription-polymerase chain reaction was used to detect the expression of IL-1alpha and vascular endothelial growth factor (VEGF) mRNA in gastric cancer cell lines with different liver metastatic potentials. Levels of VEGF secreted by human gastric cancer cells were measured by enzyme-linked immunosorbent assay. We also examined how gastric cancer cells with different metastatic potentials influence the proliferation and tube formation of human umbilical vein endothelial cells (HUVECs) using the Premix WST-1 cell proliferation assay system and an angiogenesis assay, respectively. RESULTS: IL-1alpha expression levels were significantly correlated with liver metastatic potential in gastric cancer cell lines. Levels of VEGF secreted by gastric cancer cells appear to be regulated by IL-1alpha through IL-1 receptor Type 1 and were correlated with liver metastatic potential. Both HUVEC proliferation and tube formation were strongly enhanced by coculture with high liver-metastatic gastric cancer cells and were enhanced to a similar extent by culture in the presence of IL-1alpha. In contrast, blockade of IL-1alpha inhibited both HUVEC proliferation and angiogenesis. CONCLUSIONS: IL-1alpha may play a role in liver metastasis of gastric cancer via enhanced vascular endothelial cell proliferation and angiogenesis.

Complete extragastric growth in a giant gastrointestinal stromal tumor: report of a case.

Gastrointestinal stromal tumors (GISTs) are characterized by remarkable variability in their differentiation potential, but most of these lesions do not display convincing smooth muscle or neuronal differentiation. Here we report the case of a 65-year-old woman who underwent a perfect resection of a large submucosal tumor that displayed extragastric growth. The specimen was revealed to be an elastic soft tumor, 18 x 25 x 11 cm in size. Histologically, the tumor consisted of spindle-shaped cells, with a mitotic rate of 12 per 10 high-power fields. Immunohistochemically, the tumor showed positive staining for CD34 and c-kit but negative staining for alpha-smooth muscle actin, Desmin, and s-100 protein. From these findings, the tumor was diagnosed as an uncommitted type of GIST with high-grade malignancy. This case needs careful and long-term follow-up to monitor for signs of local recurrence or distant metastasis.

[A case of diffusely infiltrating rectal cancer with pulmonary lymphangitis carcinomatosa successfully treated with mFOLFOX6 chemotherapy as salvage].

We report a case of diffusely infiltrating rectal cancer with pulmonary lymphangitis carcinomatosa that responded to mFOLFOX6 chemotherapy and enabled survival for 19 months. A 68-year-old man was admitted to our hospital for a dry cough and dyspnea. Chest X-ray and CT examination revealed prominent pulmonary markings and abnormal infiltrating shadows. Interstitial pneumonia was suspected, and we started treatment with steroid medication, but this had no effect. A colonoscopy and barium enema revealed diffusely infiltrating rectal cancer. Abdominal CT and PET showed lymphangitis carcinomatosa of the lung, paraaortic lymph node swelling, and left hydronephrosis due to rectal cancer. The patient was diagnosed with stage IV rectal cancer. Thus, a curative operation was deemed impossible. Because of subileus, we performed a decompression loop colostomy in the transverse colon, and started treatment with mFOLFOX6 chemotherapy as salvage in spite of the patient's poor respiratory condition. Though the patient's tumor markers were very high (CEA 107 ng/mL, CA19-9 7,940 U/mL) prior to chemotherapy, they decreased dramatically (CEA 49.7 ng/mL, CA19-9 772 U/mL), and subjective symptoms (dry cough and dyspnea) also improved after 2 courses. After 3 courses of treatment the patient was discharged. After 7 courses, pulmonary markings and abnormal infiltrating shadows had disappeared on chest X-ray and CT. This condition was maintained for 19 months by ambulant chemotherapy without sacrificing high quality of life. Thus, mFOLFOX6 chemotherapy could be an effective salvage regimen in cases of diffusely infiltrating rectal cancer with pulmonary lymphangitis carcinomatosa.

Antiproteases in preventing the invasive potential of pancreatic cancer cells.

The process of tumor progression and metastasis involves degradation of the extracellular matrix and is governed by an intricate balance of proteases, their activators and their inhibitors, in which malignant cells are permitted to infiltrate the adjacent structures and gain access to lymph and blood vessels. These proteases can be broadly categorized into three families: matrix metalloproteinases, serine proteinases and cysteine proteinases, all of which have all been implicated in these processes. The presence of neural invasion is often considered to be a poor prognostic sign; however, the cellular mechanisms underlying this propensity for perineural invasion are unknown. We recently researched the relationship between the glial cell line-derived neurotrophic factor and perineural invasion by human pancreatic cancer cells. We also confirmed that NF-kappa B is a part of the signaling pathway from the glial cell line-derived neurotrophic factor in human pancreatic cancer cells, and documented the inhibitory effect of gabexate mesilate, a well-known non-physiological synthetic serine protease inhibitor, for pancreatic cancer invasion. Recent studies on the role of proteases and protease inhibitors in pancreatic cancer invasion are also reviewed.

Successful paclitaxel-based chemotherapy for an alpha-fetoprotein-producing gastric cancer patient with multiple liver metastases.

BACKGROUND: Alpha-fetoprotein (AFP)-producing gastric cancer is known to frequently cause multiple liver metastases and to have an extremely poor prognosis. CASE PRESENTATION: A 64-year-old Japanese man admitted to our hospital was diagnosed with gastric cancer with liver metastases. He underwent a total gastrectomy with splenectomy, and pathological stage IV disease according to the classification proposed by the Japanese Gastric Cancer Association was assigned. The histological diagnosis was poorly differentiated adenocarcinoma, and tumor production of AFP was confirmed by immunohistochemical staining. Following surgery, the patient received combination chemotherapy consisting of TS-1 and paclitaxel. Initially, AFP levels decreased dramatically and computed tomography (CT) revealed regression of liver metastases. However, multiple new liver metastases appeared and serum AFP levels increased after 5 months. A regimen of 5-FU plus paclitaxel followed by paclitaxel monotherapy was used next. Serum AFP levels once again decreased and CT showed regression or disappearance of liver metastases. The patient currently has a very good quality of life, and is receiving weekly paclitaxel monotherapy as an outpatient. No progression of liver metastases has been observed to date. CONCLUSION: We consider this rare case to have significant value with respect to treatment of AFP-producing gastric cancer with multiple liver metastases, and propose that combining surgery with chemotherapeutic agents such as paclitaxel may lead to a better prognosis in such cases.

Effects of Helicobacter pylori infection on human pancreatic cancer cell line.

BACKGROUND/AIMS: Helicobacter species has been shown to be commonly present in extragastric human organs by polymerase chain reaction (PCR). To date, a few studies have reported that infection by Helicobacter pylori (H. pylori) was a risk factor for pancreatic malignancies, but this was not investigated very well. Therefore, we examined effects of H. pylori infection on human pancreatic cancer cells. METHODOLOGY: Interleukin (IL)-8 and vascular endothelial growth factor (VEGF) secretions by human pancreatic cancer cells which were co-cultured with H. pylori, were measured by enzyme-linked immunosorbent assay (ELISA). We then examined whether activities of proliferation factors nuclear factor-kappaB (NF-kappaB), activator protein-1 (AP-1), and serum response element (SRE) of human pancreatic cancer cells were increased by H. pylori infection. Furthermore, we examined cytotoxin-associated gene A protein (CagA) secretion into pancreatic cancer cells using Western blotting. RESULTS: IL-8 and VEGF secretion levels and activities of proliferation factors NF-kappaB, AP-1, and SRE of human pancreatic cells increased by H. pylori infection. Moreover, CagA secretion into pancreatic cancer cells was confirmed by Western blotting. CONCLUSIONS: Helicobacter pylori infection of human pancreatic cells may increase malignant potential of pancreatic cells, which seems to involve the same mechanisms as in gastric cancer cells.

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.