Expression of Forkhead box P3 in tumour cells causes immunoregulatory function of signet ring cell carcinoma of the stomach

Background:

It was recently reported that the transcription factor Forkhead box P3 (FoxP3) is expressed not only in regulatory T cells (Tregs) but also in cancer cells. The aim of this study was to clarify the clinical significance of FoxP3 expression in gastric carcinoma.

Methods:

We performed immunohistochemical staining of FoxP3 to examine the association of FoxP3 expression with clinicopathological features of 194 patients with gastric cancer who underwent surgical resection from 2000 to 2010. We also investigated the immunosuppressive function of FoxP3 using gastric cancer cell lines.

Results:

Immunohistochemical staining indicated FoxP3-positive cells within tumour tissue including both Tregs and tumour cells. Forkhead box P3-positive tumour cells were observed in 79.3% of signet ring cell carcinoma patients, and the expression of FoxP3 showed a significant correlation with lymph node metastasis. We showed that transforming growth factor-β augmented FoxP3 mRNA expression in cell lines derived from signet ring cell carcinoma. Indoleamine-2,3-dioxygenase and galectin-1, key effectors of Treg-mediated immunosuppression, were downregulated by FoxP3 knockdown.

Conclusion:

Our findings suggested that FoxP3 expression by tumour cells might have important roles in immune escape of gastric carcinoma, and be associated with the malignant potential of scirrhous gastric carcinoma.

Polymeric micelles incorporating (1,2-diaminocyclohexane)platinum (II) suppress the growth of orthotopic scirrhous gastric tumors and their lymph node metastasis

Nano-scaled drug carriers have great potential for the treatment of solid tumors. Nevertheless, hypovascularity and fibrosis in some types of solid tumors have been demonstrated to reduce the penetration and accumulation of nano-scaled drug carriers. Diffuse-type scirrhous gastric cancers present such characteristics as well as frequent metastasis to the lymph nodes; therefore, it remains a great challenge to eradicate scirrhous gastric cancers based on the drug targeting using nanocarriers. Herein, we demonstrated that polymeric micelles with 30-nm diameter incorporating (1,2-diaminocyclohexane)platinum(II) (DACHPt), the parent complex of the anticancer drug oxaliplatin, efficiently penetrated and accumulated in an orthotopic scirrhous gastric cancer model, leading to the inhibition of the tumor growth. Moreover, the elevated localization of systemically injected DACHPt-loaded micelles in metastastic lymph nodes reduced the metastatic tumor growth. These results suggest DACHPt-loaded micelles as a promising nanocarrier for the treatment of scirrhous gastric cancers and their lymphatic metastases.

An EGFR inhibitor enhances the efficacy of SN38, an active metabolite of irinotecan, in SN38-refractory gastric carcinoma cells

BACKGROUND

Acquired drug resistance to irinotecan is one of the significant obstacles in the treatment of advanced gastric cancer. This study was performed to clarify the effect of epidermal growth factor receptor (EGFR) inhibitors in combination with SN38, an active metabolite of irinotecan, on the proliferation of irinotecan-refractory gastric cancer.

METHODS

Two irinotecan-resistant gastric cancer cell lines, OCUM-2M/SN38 and OCUM-8/SN38 were, respectively, established by stepwise exposure to SN38 from the parent gastric cancer cell lines OCUM-2M and OCUM-8. The combination effects of two EGFR inhibitors, gefitinib and lapatinib, with SN38 on proliferation, apoptosis, and cell cycle on gastric cancer cells were examined.

RESULTS

Gefitinib or lapatinib showed synergistic anti-tumour effects against OCUM-2M/SN38 and OCUM-8/SN38 cells when used in combination with SN38, but not against OCUM-2M or OCUM-8 cells. SN38 increased the expression of EGFR and HER2 in OCUM-2M/SN38 and OCUM-8/SN38 cells. The combination of an EGFR inhibitor and SN38 significantly increased the levels of apoptosis-related molecules, caspase-6, p53, and DAPK-2, and resulted in the induction of apoptosis of irinotecan-resistant cells. The EGFR inhibitors increased the S-phase and decreased the UGT1A1 and ABCG expression in irinotecan-resistant cells. The SN38 plus Lapatinib group more effectively suppressed in vivo tumour growth by OCUM-2M/SN38 cells than either alone group.

CONCLUSION

The combination treatment with an EGFR inhibitor and irinotecan might produce synergistic anti-tumour effects for irinotecan-refractory gastric cancer cells. The regulation of SN38 metabolism-related genes and cell cycle by EGFR inhibitors might be responsible for the synergism.

Upregulation of cancer-associated myofibroblasts by TGF-β from scirrhous gastric carcinoma cells

BACKGROUND

Myofibroblasts in the cancer microenvironment have recently been implicated in tumour growth and metastasis of gastric cancer. However, the mechanisms responsible for the regulation of myofibroblasts in cancer-associated fibroblasts (CAFs) remain unclear. This study was performed to clarify the mechanisms for regulation of myofibroblasts in gastric cancer microenvironment.

METHODS

Two CAFs (CaF-29 and CaF-33) from the tumoural gastric wall and a normal fibroblast (NF-29) from the nontumoural gastric wall, 4 human gastric cancer cell lines from scirrhous gastric cancer (OCUM-2MD3 and OCUM-12), and non-scirrhous gastric cancer (MKN-45 and MKN-74) were used. Immunofluorescence microscopy by triple-immunofluorescence labelling (α-SMA, vimentin, and DAPI) was performed to determine the presence of α-SMA-positive myofibroblasts. Real-time RT-PCR was performed to examine α-SMA mRNA expression.

RESULTS

Immunofluorescence microscopy showed that the frequency of myofibroblasts in CaF-29 was greater than that in NF-29. The number of myofibroblasts in gastric fibroblasts gradually decreased with serial passages. Transforming growth factor-β (TGF-β) significantly increased the α-SMA expression level of CAFs. Conditioned medium from OCUM-2MD3 or OCUM-12 cells upregulated the α-SMA expression level of CAFs, but that from MKN-45 or MKN-74 cells did not. The α-SMA upregulation effect of conditioned medium from OCUM-2MD3 or OCUM-12 cells was significantly decreased by an anti-TGF-β antibody or Smad2 siRNA.

CONCLUSION

Transforming growth factor-β from scirrhous gastric carcinoma cells upregulates the number of myofibroblasts in CAFs.

Transforming growth factor-β decreases the cancer-initiating cell population within diffuse-type gastric carcinoma cells

Stem cells in normal tissues and cancer-initiating cells (CICs) are known to be enriched in side population (SP) cells. However, the factors responsible for the regulation of expression of ABCG2, involved in efflux of dyes, in SP cells have not been fully investigated. Here, we characterized the SP cells within diffuse-type gastric carcinoma, and examined the effects of transforming growth factor-β (TGF-β) on SP cells. Diffuse-type gastric carcinoma cells established from four independent patients universally contained SP cells between 1 and 4% of total cells, which displayed greater tumorigenicity than non-SP cells did. TGF-β repressed the transcription of ABCG2 through direct binding of Smad2/3 to its promoter/enhancer, and the number of SP cells and the tumor-forming ability of cancer cells were decreased by TGF-β, although ABCG2 is not directly involved in the tumor-forming ability of SP cells. Cancer cells from metastatic site expressed much higher levels of ABCG2 and included a greater percentage of SP cells than parental cancer cells did. SP cells are thus responsible for the progression of diffuse-type gastric carcinoma, and TGF-β negatively contributes to maintain the CICs within the cancer.

Transforming growth factor-β decreases the cancer-initiating cell population within diffuse-type gastric carcinoma cells

Stem cells in normal tissues and cancer-initiating cells (CICs) are known to be enriched in side population (SP) cells. However, the factors responsible for the regulation of expression of ABCG2, involved in efflux of dyes, in SP cells have not been fully investigated. Here, we characterized the SP cells within diffuse-type gastric carcinoma, and examined the effects of transforming growth factor-β (TGF-β) on SP cells. Diffuse-type gastric carcinoma cells established from four independent patients universally contained SP cells between 1 and 4% of total cells, which displayed greater tumorigenicity than non-SP cells did. TGF-β repressed the transcription of ABCG2 through direct binding of Smad2/3 to its promoter/enhancer, and the number of SP cells and the tumor-forming ability of cancer cells were decreased by TGF-β, although ABCG2 is not directly involved in the tumor-forming ability of SP cells. Cancer cells from metastatic site expressed much higher levels of ABCG2 and included a greater percentage of SP cells than parental cancer cells did. SP cells are thus responsible for the progression of diffuse-type gastric carcinoma, and TGF-β negatively contributes to maintain the CICs within the cancer.

Elevated dietary linoleic acid increases gastric carcinoma cell invasion and metastasis in mice

BACKGROUND

Dietary (n-6)-polyunsaturated fatty acids influence cancer development, but the mechanisms have not been well characterised in gastric carcinoma.

METHODS

We used two in vivo models to investigate the effects of these common dietary components on tumour metastasis. In a model of experimental metastasis, immunocompromised mice were fed diets containing linoleic acid (LA) at 2% (LLA), 8% (HLA) or 12% (VHLA) by weight and inoculated intraperitoneally (i.p.) with human gastric carcinoma cells (OCUM-2MD3). To model spontaneous metastasis, OCUM-2MD3 tumours were grafted onto the stomach walls of mice fed with the different diets. In in vitro assays, we investigated invasion and ERK phosphorylation of OCUM-2MD3 cells in the presence or absence of LA. Finally, we tested whether a cyclooxygenase (COX) inhibitor, indomethacin, could block peritoneal metastasis in vivo.

RESULTS

Both the HLA and VHLA groups showed increased incidence of tumour nodules (LA: 53%; HLA: 89%; VHLA: 100%; P<0.03); the VHLA group also displayed increased numbers of tumour nodules and higher total volume relative to LLA group in experimental metastasis model. Both liver invasion (78%) and metastasis to the peritoneal cavity (67%) were more frequent in VHLA group compared with the LLA group (22% and 11%, respectively; P<0.03) in spontaneous metastasis model. We also found that the invasive ability of these cells is greatly enhanced when exposed to LA in vitro. Linoleic acid also increased invasion of other scirrhous gastric carcinoma cells, OCUM-12, NUGC3 and MKN-45. Linoleic acid effect on OCUM-2MD3 cells seems to be dependent on phosphorylation of ERK. The data suggest that invasion and phosphorylation of ERK were dependent on COX. Indomethacin decreased the number of tumours and total tumour volume in both LLA and VHLA groups. Finally, COX-1, which is known to be an important enzyme in the generation of bioactive metabolites from dietary fatty acids, appears to be responsible for the increased metastatic behaviour of OCUM-2MD3 cells in the mouse model.

CONCLUSION

Dietary LA stimulates invasion and peritoneal metastasis of gastric carcinoma cells through COX-catalysed metabolism and activation of ERK, steps that compose pathway potentially amenable to therapeutic intervention.

Theophylline inhibits the differentiation of human monocyte into dendritic cell potentially via adenosine receptor antagonism

BACKGROUND

Theophylline has an anti-inflammatory action that may account for its clinical effectiveness in the reduction of inflammatory cells in the airways. Dendritic cells (DCs) are professional antigen-presenting cells, capable of priming naïve T cells, and play key roles in the activation of immune responses in asthma.

OBJECTIVE

The purpose of this study was to investigate the effects of theophylline on human monocyte differentiation into DCs and whether this involved antagonism of adenosine receptors.

METHODS

Peripheral human blood monocytes were cultured in the presence of granulocyte/macrophage-colony stimulating factor and IL-4 to induce DC differentiation. The cells were incubated with theophylline, KF17837 (a selective A2a receptor antagonist) and enprofylline (A2b receptor antagonist) and co-incubated with selective adenosine A1 and A2a receptor agonists, a phosphodiesterase inhibitor (rolipram) and adenosine deaminase (ADA) to determine their effects on DC differentiation. In addition, depletion of adenosine receptors by small interfering RNA (siRNA) was also examined.

RESULTS

Monocytes differentiated into myeloid DCs in the culture system. The number of DCs was remarkably reduced by 60-70% when theophylline was administered at a therapeutic concentration. This effect was concentration-dependently exacerbated, was partly mediated by cellular apoptosis and was effectively reversed by the addition of the A1 agonists [2-chloro-N(6)-cyclopentyladenosin, N(6)-cyclohexyladenosine, and N-ethylcarboxamidoadenosine (NECA)] or the A2a agonist (CGS-21680, NECA). The depletion of the adenosine A1 receptor by siRNA and addition of ADA remarkably reduced DC differentiation. Meanwhile, both enprofylline and rolipram had little effect.

CONCLUSION

Our findings suggest that the adenosine A1 (and possibly coordinated with A2a) receptors contribute to DC differentiation and survival. These findings provide further evidence that theophylline has an anti-inflammatory action in bronchial asthma.

The effect of ascorbate on minor recurrent aphthous stomatitis

AIM

Minor recurrent aphthous stomatitis (MRAS) is a common, painful and inflammatory ailment of the oral cavity with juvenile onset and unknown aetiology. The purpose of this study was to evaluate the potential of ascorbate (vitamin C) to reduce the frequency of MRAS and severity of pain.

PATIENTS AND METHODS

Sixteen MRAS patients (9 boys and 7 girls: mean age, 12.0 +/- 2.4 years old) were assigned to take an oral dosage of 2000 mg/m(2)/day ascorbate.

SUBJECTS

Their baseline frequency of outbreaks and the level of pains were compared during the treatment; in addition, a crossover clinical trial was performed. Polymorphonuclear leucocytes play a role in the pathogenesis, and then superoxide anion production was evaluated in prior to ascorbate treatment.

RESULTS

The data indicated a statistically significant 50% reduction in oral ulcer outbreaks and a decline of pain level. Neutrophils were primed for superoxide anion production in the patients with MRAS.

CONCLUSION

Ascorbate may modulate the generation of reactive oxygen species and augment neutrophil apoptosis, which could prevent neutrophil-mediated inflammation. Ascorbate seems to be effective, but the findings of our study were preliminary and it should be re-evaluated with a larger randomized controlled clinical trials.

Inhibitory effect of a TGFbeta receptor type-I inhibitor, Ki26894, on invasiveness of scirrhous gastric cancer cells

Background:

Gastric cancer cells frequently metastasise, partly because of their highly invasive nature. Transforming growth factor-β (TGF-β) receptor signalling is closely associated with the invasion of cancer cells. The aim of this study was to clarify the effect of a TGF-β receptor (TβR) phosphorylation inhibitor on the invasiveness of gastric cancer cells.

Methods:

Four gastric cancer cell lines, including two scirrhous-type cell lines and two non-scirrhous-type cell lines, were used. A TβR type I (TβR-I) kinase inhibitor, Ki26894, inhibits the phosphorylation of Smad2 at an ATP-binding site of TβR-I. We investigated the expression levels of TβR and phospho-Smad2, and the effects of TGF-β in the presence or absence of Ki26894 on Smad2 phosphorylation, invasion, migration, epithelial-to-mesenchymal transition (EMT), Ras homologue gene family member A (RhoA), ZO-2, myosin, and E-cadherin expression of gastric cancer cells.

Results:

TβR-I, TβR-II, and phospho-Smad2 expressions were found in scirrhous gastric cancer cells, but not in non-scirrhous gastric cancer cells. Ki26894 decreased Smad2 phosphorylation induced by TGF-β1 in scirrhous gastric cancer cells. Transforming growth factor-β1 upregulated the invasion, migration, and EMT ability of scirrhous gastric cancer cells. Transforming growth factor-β1 significantly upregulated the activity of RhoA and myosin phosphorylation, whereas TGF-β1 decreased ZO-2 and E-cadherin expression in scirrhous gastric cancer cells. Interestingly, Ki26894 inhibited these characteristics in scirrhous gastric cancer cells. In contrast, non-scirrhous gastric cancer cells were not affected by TGF-β1 or Ki26894 treatment.

Conclusion:

A TβR-I kinase inhibitor decreases the invasiveness and EMT of scirrhous gastric cancer cells. Ki26894 is therefore considered to be a promising therapeutic compound for the metastasis of scirrhous gastric carcinoma.

Direct cancer-stromal interaction increases fibroblast proliferation and enhances invasive properties of scirrhous-type gastric carcinoma cells

BACKGROUND

Scirrhous-type gastric carcinoma (SGC) exhibits an extensive submucosal fibrosis and extremely poor patient prognosis. We investigated the importance of the cancer-stromal interaction in the histogenesis of SGC.

METHODS

Gastric fibroblasts NF-25 and intestinal fibroblasts NF-j2 were co-cultured with SGC-derived (HSC-39) or non-SGC-derived (HSC-57 and HSC-64) cells. To identify genes that are up- or downregulated in NF-25, complementary DNA (cDNA) microarray analysis was performed. The antibody against vascular-cell adhesion molecule-1 (VCAM-1) was used for cell growth test and immunohistochemistry. Moreover, the impact of interaction with NF-25 fibroblasts on HSC-39 cells was investigated using western blot and reverse transcription-polymerase chain reaction.

RESULTS

HSC-39 cells stimulated growth of NF-25 but not NF-j2 when co-cultured. Induction of VCAM-1 in NF-25 fibroblasts was identified, which was specific when co-cultured with HSC-39 but not with non-SGC-derived HSC-57 and HSC-64 cells. Neutralising antibody to VCAM-1 suppressed NF-25 growth in dose-dependent manners. In tissue samples, positive immunoreactivity of VCAM-1 in SGC-derived fibroblasts was significantly higher than that in non-SGC-derived fibroblasts. Furthermore, interaction with NF-25 fibroblasts not only induced the epithelial-mesenchymal transition-like change, but also expressions of matrix metalloproteinase- related genes in HSC-39 cells.

CONCLUSION

Direct interaction between SGC cells and gastric fibroblasts establishes the tumour microenvironment and reinforces the aggressiveness of SGC.

Effects of VEGFR-3 phosphorylation inhibitor on lymph node metastasis in an orthotopic diffuse-type gastric carcinoma model

BACKGROUND

Vascular endothelial growth factor receptor-3 (VEGFR-3) signalling mediates lymphangiogenesis and lymphatic invasion; however, the effect of VEGFR-3 inhibition on the lymph node (LN) metastasis remains unclear. The aim of this study is to clarify the benefit of a VEGFR-3 inhibitor Ki23057 for LN metastasis.

METHODS

Ki23057 was administered orally to gastric cancer models created by orthotopic inoculation of diffuse-type gastric cancer cells, OCUM-2MLN. The effects of Ki23057 on lymphatic vessel invasion, lymphatic vessel density, and VEGFR-3 phosphorylation were examined by immunostaining or immunoblotting.

RESULTS

Ki23057 inhibited the autophosphorylation of VEGFR-3, with IC50 values of 4.3 nM in the cell-free kinase assay. Murine gastric cancer models created by the orthotopic inoculation of OCUM-2MLN cells showed the diffusely infiltrating growth and frequently developed LN metastasis. The oral administration of Ki23057 significantly (P<0.01) reduced the size of orthotopic tumours and the number of the metastatic LN in gastric cancer models. The degree of lymphatic invasion and lymphangiogenesis was significantly (P<0.05) lower in the gastric tumours treated by Ki23057. Ki23057 inhibited the phosphorylation of VEGFR-3 of lymphatic endothelial cells in gastric tumours.

CONCLUSION

The inhibition of lymphangiogenesis targeting VEGFR-3 phosphorylation is a therapeutic strategy for inhibiting LN metastasis of diffuse-type gastric cancer.

Thalidomide prevents formation of multinucleated giant cells (Langhans-type cells) from cultured monocytes: possible pharmaceutical applications for granulomatous disorders

Thalidomide is an effective drug for chronic inflammatory diseases, but the mechanism underlying its immunomodulatory action remains uncertain. Thalidomide has been reported to clinically improve chronic inflammatory granulomatous disorders. In such disorders, the granulomas consist of epithelioid cells, scattered lymphocytes and multinucleated giant cells (MNGC; Langhans-type cells). The present experimental approach permitted the reproduction of MNGC formation from peripheral blood monocytes and examination of thalidomides effect on it. MNGC can be effectively generated from monocytes cultured in the presence of interleukin-4 (IL-4) and macrophage colony-stimulating factor(M-CSF) for 14 days. Thalidomide can inhibit the formation of MNGC in a dose-dependent manner. MNGC formation was partly inhibited by the presence of neutralizing TNF-alpha antibody in the responses induced by IL-4 and M-CSF. Autocrinal TNF-alpha production and modulation of cadhelin expression to regulate cell adhesion might be involved in this inhibitory action of thalidomide. Our results support thalidomides clinical efficacy in the treatment of chronic granulomatous disorders (granulomatosis).

Multi-nucleated giant cell formation from human cord blood monocytes in vitro, in comparison with adult peripheral blood monocytes

Multi-nucleated giant cells (MGCs; Langhans-type cell), formed from macrophage fusion, are recognized as a hallmark histological feature in chronic inflammation. However, their precise pathological role is still poorly understood, especially for microorganism pathogens in the neonatal immune system, which are capable of surviving intracellularly in phagocytes. To conduct a partial evaluation of the monocyte function of neonates, we investigated the ability of human cord blood monocytes to form MGCs in vitro by stimulating various cytokines and comparing them with adult peripheral blood monocytes. Monocytes from cord blood and adult peripheral blood were isolated and cultured for 14 days with cytokines known to induce MGC in vitro. The fusion index in experiments with a combination of interleukin (IL)-4 and macrophage colony-stimulating factor (M-CSF) and a combination of IL-4 and granulocyte-macrophage colony-stimulating factor (GM-CSF) was significantly lower in cord blood than in adult blood monocytes (P = 0.0018 and P = 0.0141, respectively). The number of nuclei per MGC was significantly lower in cord blood than in adult blood monocytes in experiments with IL-4 alone, the combination of IL-4 and M-CSF, and the combination of IL-4 and GM-CSF (P < 0.0001). These results suggest the possibility that the susceptibility of newborns to mycobacterium infection is due partly to impaired MGC formation.

Prognostic impact of PCR-based identification of isolated tumour cells in the peritoneal lavage fluid of gastric cancer patients who underwent a curative R0 resection

Identification of cancer cells in the peritoneal cavity could influence therapy and outcome of gastric carcinoma patients. The objective of this study was to evaluate the clinical impact of the real-time quantitative polymerase chain reaction-(PCR) based identification of isolated tumour cells in the peritoneal lavage fluid of gastric carcinoma. The peritoneal lavage fluid of 116 patients with gastric cancer was sampled at laparotomy. After RNA extraction and reverse transcription, real-time quantitative PCR was performed using the primers and probes for carcinoembryonic antigen (CEA) and cytokeratin-20 (CK20). When either the CEA mRNA or CK20 mRNA level of the sample was over the cutoff value, the sample was determined to be PCR-positive. Forty-six (40%) of the 116 patients were PCR-positive and 30 (65%) of the 46 PCR-positive patients died as a result of recurrent peritoneal dissemination. The prognosis of the 46 PCR-positive patients was significantly (P<0.001) worse than that of 70 PCR-negative patients. Furthermore, in 80 of the cases with a curative R0 resection, 15 of the patients with PCR-positive findings had a significantly (P<0.001) poorer prognosis than the 65 PCR-negative patients. The prognosis of the PCR-positive patients was significantly poorer than that of the PCR-negative patients in the T3 (P<0.0001) and T4 (P=0.048) subgroups. In a multivariate analysis of the 80 cases with a curative R0 resection, the real-time quantitative RT–PCR (CEA and/or CK20) levels indicated that they were independent prognostic factors. The real-time quantitative RT–PCR analysis of the CEA and/or CK20 transcripts in the peritoneal lavage fluid is useful for predicting the peritoneal recurrence in patients who are undergoing a curative resection for gastric cancer.

Clinical significance of ERas oncogene on cancer

15083

Background: Embryonic stem (ES) cells are pluripotent cells derived from early mammalian embryos. When ES cells are subcutaneously injected into immunodeficient or isogenic mice, a teratoma is formed within a few weeks. This tumor is composed of all three germ layers in a disorganized fashion. Thus there could be some common molecular mechanisms shared by ES cells and somatic cancer cells. The ERas oncogene is a recently identified gene that supports the tumorigenic growth of ES cells by producing a constitutively active Ras protein. There have been no report about expression of ERas oncogene on cancer cells until now. The aim of this study is to investigate expression and clinical significance of ERas oncogene on cancer cell lines and clinical cancer tissues. Methods: A panel of 35 human cancer cell lines, 5 normal cell lines, and 20 patiants with gastric cancer tissues were used in this study. ERas mRNA expression was examined by reverse transcription-polymerase chain reaction. The effect of the DNA methyl transferase inhibitor, 5-aza-2’- deoxycitydine on the ERas expression was analyzed. Methylation of CpG islands of ERas promoter lesion was investigated using bisulfate-directsequence analysis. Results: Expression of ERas mRNA was not found in any normal cells. In contrast, ERas mRNA was found in 15 of 35 cancer cell lines, including 8 of 15 gastric cancers, 4 of 7 colorectal cancers, 2 of 6 pancreas cancers, 1 of 3 breast cancers and none of esophageal cancers. Eras mRNA was found in all gastric cancer tissues, but not normal tissues. 5-aza-2’-deoxycytidine treatment at 2, 5, and 10μM for 24 h resulted in ERas expression in 10 of 20 cancer cell lines with respect to the silencing of ERas, including 7 of 7 gastric cancers, 1 of 3 colorectal cancers and 2 of 3 breast cancers. Methylation of CpG island were found in the cancer cell lines without ERas expression, but not in these with ERas expression. Conclusions: ERas oncogene is associated with the carcinogenesis pathway in human cancer. Eras might be useful marker for cancer diagnosis.

No significant financial relationships to disclose.

A novel K-samII/FGF-R2 autophosphorylation inhibitor is therapeutically useful for scirrhous gastric carcinoma with K-samII amplification

14070

Background: Scirrhous gastric carcinoma, a diffusely infiltrating also known as linitis plastica-type carcinoma, carries the highest mortality of all gastric cancers. Scirrhous carcinoma cells with amplification of the activated K-samII gene, which encodes fibroblast growth factor receptor type 2 (FGF-R2), have a growth advantage during tumor progression The poor prognosis carried by scirrhous gastric cancer is closely associated with amplification of the K-samII/FGF-R2, a tyrosine kinase growth factor receptor. Ki23057, a newly developed small molecule acting K-samII/FGF-R2 inhibitor, is a kinase inhibitor that competes with ATP for the binding site in the kinase, thus strongly blocking phosphorylation of FGF-R2. The aim of the current study is to clarify the possibility of molecular target therapy with Ki23057 for treating scirrhous gastric cancer. Methods: Five human gastric cancer cell lines were used. OCUM-2MD3 and OCUM-8 were derived from scirrhous carcinomas. MKN-7, MKN-45 and MKN-74 cells were derived from non-scirrhous carcinomas. In vitro effects of Ki23057 on cell growth were determined by calculating the number of cancer cells. The influences of Ki23057 on the MAP kinase and PI3 kinase signaling pathways and the apoptosis pathway in the gastric cancer cells were also examined. For in vivo experiments, the Ki23057 was administered orally to mouse models of peritoneal dissemination. Results: K-samII amplification was found in OCUM-2MD3 and OCUM-8 cells, but not in MKN-7, MKN-45, or MKN-74 cells. Ki23057 significantly inhibited the proliferation of scirrhous cancer cells, but not non- scirrhous gastric carcinoma cells. Ki23057 decreased phosphorylation of K-samII/FGF-R2, ERK and Akt, and increased apoptosis in scirrhous cancer lines. The oral Ki23057 administration significantly (p<0.001) prolonged survival of mice with peritoneal dissemination following injection of OCUM-2MD3 scirrhous cancer cells. Conclusions: A novel K-samII/FGF-R2 phosphorylation inhibitor, Ki23057, appears therapeutically promising in scirrhous gastric carcinoma with K-samII amplification.

No significant financial relationships to disclose.

TGF-beta1 down-regulates ICAM-1 expression and enhances liver metastasis of pancreatic cancer

PURPOSE

In order to study the regulation of adhesion-molecule expression by cytokines, we have investigated the effect of transforming growth factor-beta1. (TGF-beta1) on the expression of intercellular adhesion molecule-1 (ICAM-1) in human pancreatic cancer cell lines.

MATERIAL AND METHODS

By using three pancreatic cancer cell lines, SW1990, CAPAN-2 and PANC-1, the effect of TGF-beta1 on expression of ICAM-1, cancer cell immunogenicity and liver metastasis were investigated.

RESULTS

Cell surface ICAM-1 expression by ELISA on three cell lines were all reduced significantly by following incubation with various concentrations of TGF-beta1 and down-regulation of ICAM-1 expression was also observed at the mRNA level. Corresponding to the down expression of ICAM-1, the adhesion of peripheral blood mononuclear lymphocytes (PBMLs) to cancer cells and cancer cell cytotoxicity during co-culture with PBMLs were remarkably decreased by treatment with TGF-beta1. Furthermore, enhanced liver metastatic potential by in vivo splenic injection was observed in CAPAN-2 cells pretreated with TGF-beta1.

CONCLUSIONS

Since decreased expression of ICAM-1 has been known to contribute to cancer cell escape from immunologic recognition and cytotoxicity by effector cells, the present results indicate that unknown function of TGF-beta1 in the tumor progression and metastasis of pancreatic cancer.

Relationship between Filtration Coefficients of Microvasculature and Levels of Atrial Natriuretic Peptide or Echocardiographic Measurements

BACKGROUND/AIMS

Assessing the volume status of hemodialysis (HD) patients and determining their adequate dry weight (DW) present great challenges for physicians involved in HD. In this study the relationship between standardized filtration coefficients of microvasculature (Lpst) and the plasma atrial natriuretic peptide (ANP) levels or echocardiographic measurements (UCGm) were clarified. The aim of this study was to evaluate the possibility of utilizing Lpst as one of the tools for assessing volume status of patients undergoing HD.

METHODS

52 patients on maintenance HD were examined. Lpst was calculated by utilizing continuous measurements of blood volume during HD by means of monitoring changes of hematocrit with CRIT-LINE(TM). Plasma ANP levels were measured shortly after HD. Plasma ANP levels were elevated beyond the normal limit in 32 patients (Hi group) and were within the normal range in the remaining 20 patients (Lo group). UCGm were performed within 1 month prior to the study. Inferior vena cava diameters in quiet expiration (IVCe) were dilated in 21 patients (Hivc group) and were within the normal range in the remaining 31 patients (Livc group). Lpst was compared with plasma ANP level and UCGm.

RESULTS

Lpst in Lo group were significantly lower than those in the Hi group (0.83+/-0.19 vs. 2.64+/-2.73 ml/mm Hg/min; p<0.001). Lpst correlated significantly with plasma ANP levels (r=0.613; p<0.001). Lpst in the Livc group were significantly lower than those in the Hivc group (1.33+/-1.61 vs. 2.85+/-2.88 ml/mm Hg/min; p<0.001). Lpst also correlated with IVCe (r=0.630; p<0.001). The receiver operating characteristic (ROC) curves for high plasma ANP level and for dilated IVCe were significant for Lpst. Area under the ROC curve for elevated ANP was 0.909 (95% confidence interval (CI) 0.834-0.985) and for dilated IVCe was 0.833 (95% CI 0.724-0.941).

CONCLUSION

We conclude that there exists a significant association between Lpst and plasma ANP levels at the end of a dialysis session. There is a possibility that high plasma ANP levels cause elevation of Lpst. Besides ANP, Lpst significantly correlated with IVCe. These results suggested that Lpst can be utilized as one of the tools for assessing volume status of patients undergoing HD.

Estimation of filtration coefficients and circulating plasma volume by continuously monitoring hematocrit during hemodialysis

BACKGROUND/AIMS

Filtration coefficients (Lp) and plasma volume were estimated in order to investigate whether suppressed Lp associates with intradialytic hypotension and/or diabetic nephropathy.

METHODS

Twenty-one patients were evaluated. Nine patients were diabetic (DM) and 12 were nondiabetic (non-DM). Three of DM and 4 of non-DM were prone to dialysis-induced hypotension (hypo(+)) and others (hypo(-)) were not. Changes in hematocrit (Ht) were measured for 60 min after the start of ultrafiltration. Lp and plasma volume at the start of ultrafiltration (Vp0) were estimated to fit calculating values of Ht based on Schneditz's open two compartment model to actual value.

RESULTS

There was no significant difference in the mean values of Lp/Vp0 either between hypo(+) and hypo(-) (0.87 +/- 0.37 vs. 1.24 +/- 0.48 ml/mm Hg.min.liter; n.s.) or between DM and non-DM (1.04 +/- 0.32 vs. 1.17 +/- 0.56 ml/mm Hg.min. liter; n.s.). However, the comparisons of Lp/Vp0 among the four groups (hypo(+)/DM, hypo(-)/DM, hypo(+)/non-DM and hypo(-)/non-DM) showed significant differences between hypo(+)/non-DM and hypo(-)/non-DM (1.08 +/- 0.40, 1.02 +/- 0.32, 0.71 +/- 0.29*, 1.40 +/- 0.53* ml/mm Hg.min.liter; *p < 0.05). Differences in the percentage of Vp0 to body weight (Vp0/BW) among four groups and correlation between Lp/Vp0 and Vp0/BW were not significant.

CONCLUSION

These data indicated that reduction of Lp/Vp0 was not simply caused by decreased circulating plasma volume (Vp0/BW) and that the suppressed filtration coefficients may have substantial association with dialysis-induced hypotension in non-DM. The estimation of Lp using in-line measurement of Ht was a useful method for analyzing intradialytic hypotension.

Kawasaki disease in parents and children

AIM

To estimate the probability that the parents of patients with Kawasaki disease also had a history of the same disease.

METHODS

Self-reported parents' histories of Kawasaki disease were collected from data of the 16th nationwide survey of the disease conducted in Japan from January 1999 to December 2000. The incidence of Kawasaki disease was calculated by using data reported in all 16 nationwide surveys and live births in the Japanese vital statistics. The expected number of parents with a history of Kawasaki disease in the general population, which was calculated by using the assumed number of parents in the vital statistics and the incidence of this disease, was compared with the observed number.

RESULTS

Among 14,163 parent pairs of patients with Kawasaki disease, 33 parents (25 mothers and 8 fathers) had a history of the disease. The number of parents expected to have a history of Kawasaki disease was 16.1 (8.4 mothers and 7.7 fathers). From a Poisson distribution, the probability of the observed number was less than 0.001 among parents or mothers. The prevalence of a recurrence of Kawasaki disease and incidences involving siblings of patients whose parents had a history of the disease were five or six times higher than those of all patients who were reported in the 16th survey.

CONCLUSION

When compared with parents in the general population, the probability of a history of Kawasaki disease was significantly higher in those parents whose children suffered from the same disease. This suggests that, epidemiologically, a genetic predisposition to Kawasaki disease may be implicated in its occurrence.