TGF-beta suppresses tumor progression in colon cancer by inhibition of IL-6 trans-signaling

Alterations of TGF-beta signaling have been described in colorectal cancer, although the molecular consequences are largely unknown. By using transgenic mice overexpressing TGF-beta or a dominant-negative TGF-betaRII, we demonstrate that TGF-beta signaling in tumor infiltrating T lymphocytes controls the growth of dysplastic epithelial cells in experimental colorectal cancer, as determined by histology and a novel system for high-resolution chromoendoscopy. At the molecular level, TGF-beta signaling in T cells regulated STAT-3 activation in tumor cells via IL-6. IL-6 signaling required tumor cell-derived soluble IL-6R rather than membrane bound IL-6R and suppression of such TGF-beta-dependent IL-6 trans-signaling prevented tumor progression in vivo. Taken together, our data provide novel insights into TGF-beta signaling in colorectal cancer and suggest novel therapeutic approaches for colorectal cancer based on inhibition of TGF-beta-dependent IL-6 trans-signaling.

Inhibition of IL-6 for the treatment of inflammatory diseases

Interleukin-6 (IL-6) is a pleiotropic cytokine with various biological activities. Deregulated overproduction of IL-6 has been found to play pathological roles in chronic inflammatory diseases such as rheumatoid arthritis, Castleman's disease, juvenile idiopathic arthritis and Crohn's disease. Humanized anti-IL-6 receptor antibody has been developed as a therapeutic agent for these diseases, and therapeutic benefits have been revealed in clinical studies.

Humanized Anti-Interleukin 6 Receptor Antibody Induced Long-term Remission in a Patient with Life-Threatening Refractory Autoimmune Hemolytic Anemia

Refractory autoimmune hemolytic anemia (AIHA) is associated with considerable rates of mortality. Interleukin 6 (IL-6) has been reported to play a role in the pathogenesis of AIHA. This report describes a patient with AIHA who was successfully treated with a humanized anti-human IL-6 receptor (IL-6R) monoclonal antibody (MoAb). He had experienced life-threatening AIHA and had received conventional therapy with corticosteroids, azathioprine, cyclophosphamide, cyclosporin A, melphalan, plasma exchange, and irradiation to his spleen. However, the patient's symptoms and laboratory data did not show a sufficient improvement. Because his serum IL-6 level was elevated, we attempted to block IL-6 signaling by using a humanized anti-IL-6R MoAb, MRA. With 8 mg/kg of MRA administration every 2 weeks, the serum hemoglobin level gradually increased and normalized within 4 months. After 2 years of MRA treatment, the disease activity was well controlled without adverse reactions. Anti-IL-6R MoAb can be a novel and effective therapeutic agent for AIHA.

Anti-interleukin 6 receptor antibody inhibits murine AA-amyloidosis

OBJECTIVE

AA-amyloidosis is a severe complication in chronic inflammatory diseases. AA-amyloidosis is caused by the deposition of insoluble fibrils containing AA amyloid protein derived from serum amyloid A (SAA), which is synthesized by inflammatory cytokine stimulation. We examined whether anti-interleukin 6 receptor (IL-6R) antibody prevented the development of AA-amyloidosis in mouse models.

METHODS

A transient model was induced by the injection of amyloid enhancing factor (AEF) and adjuvant treatment in C57BL/6 mice. Monoclonal IgG1 antibody, MR16-1, was injected intraperitoneally just once before the injection of AEF and adjuvant. After 2 and 5 weeks, mice were sacrificed and histologically examined. In contrast, a chronic model was induced by AEF injection into IL-6 transgenic mice. One week later, in order to avoid neutralizing antibody production, MR16-1 (200 mg/kg) was injected intravenously. MR16-1 (5 mg/kg) was injected subcutaneously twice a week from the next week. Three and 6 weeks after AEF injection, mice were sacrificed and histologically examined.

RESULTS

In the transient model, amyloid deposition was observed in the spleen, liver, and kidney as early as 2 weeks after treatment. MR16-1 completely prevented amyloid deposition. Although IL-6 production was not suppressed, SAA production was significantly suppressed. In the chronic model, substantial amyloid deposition was seen in multiple organs and tissues as well as the spleen, liver, and kidney. MR16-1 suppressed amyloid deposition in many organs, even when injected one week after AEF injection; it showed a tendency to decrease SAA and IL-6 levels were decreased.

CONCLUSION

IL-6 is a key cytokine for the induction of AA-amyloidosis, and anti-IL-6R therapy appears promising for the treatment of AA-amyloidosis.

A pilot randomized trial of a human anti-interleukin-6 receptor monoclonal antibody in active Crohn's disease

BACKGROUND & AIMS

Interleukin-6 (IL-6) regulates immune response and inflammation. We carried out a pilot placebo-controlled study to investigate the efficacy, pharmacokinetics, and safety of MRA, a humanized monoclonal antibody to IL-6 receptor, in patients with active Crohn's disease.

METHODS

Thirty-six patients with active Crohn's disease (Crohn's Disease Activity Index [CDAI] > or =150) were randomly assigned to receive biweekly intravenous infusion of either placebo, MRA, or MRA/placebo alternately for 12 weeks at a dose of 8 mg/kg. The study's primary end point was a clinical response rate that was defined as a reduction of CDAI > or =70.

RESULTS

At the final evaluation, 80% of the patients (8 of 10) given biweekly MRA had a clinical response as compared with 31% of the placebo-treated patients (4 of 13; P = 0.019). Twenty percent of the patients (2 of 10) on this regimen went into remission (CDAI <150), as compared with 0% of the placebo-treated patients (0 of 13). The clinical response rate of the every-4-week regimen was 42% (5 of 12). The serum concentrations of MRA were detected at 2 weeks after every infusion, at which time acute phase responses were completely suppressed; however, they were not suppressed at 4 weeks. Endoscopic and histologic examination showed no difference between MRA and placebo groups. The incidence of adverse events was similar in all the groups.

CONCLUSIONS

This is the first clinical trial of humanized anti-IL-6 receptor monoclonal antibody in Crohn's disease. A biweekly 8 mg/kg infusion of MRA was well tolerated, normalized the acute-phase responses, and suggests a clinical effect in active Crohn's disease.

Treatment of rheumatoid arthritis with humanized anti-interleukin-6 receptor antibody: A multicenter, double-blind, placebo-controlled trial

OBJECTIVE

Interleukin-6 (IL-6) is a pleiotropic cytokine that regulates the immune response, inflammation, and hematopoiesis. Overproduction of IL-6 plays pathologic roles in rheumatoid arthritis (RA), and the blockade of IL-6 may be therapeutically effective for the disease. This study was undertaken to evaluate the safety and efficacy of a humanized anti-IL-6 receptor antibody, MRA, in patients with RA.

METHODS

In a multicenter, double-blind, placebo-controlled trial, 164 patients with refractory RA were randomized to receive either MRA (4 mg/kg body weight or 8 mg/kg body weight) or placebo. MRA was administered intravenously every 4 weeks for a total of 3 months. The clinical responses were measured using the American College of Rheumatology (ACR) criteria.

RESULTS

Treatment with MRA reduced disease activity in a dose-dependent manner. At 3 months, 78% of patients in the 8-mg group, 57% in the 4-mg group, and 11% in the placebo group achieved at least a 20% improvement in disease activity according to the ACR criteria (an ACR20 response) (P < 0.001 for 8-mg group versus placebo). Forty percent of patients in the 8-mg group and 1.9% in the placebo group achieved an ACR50 response (P < 0.001). The overall incidences of adverse events were 56%, 59%, and 51% in the placebo, 4-mg, and 8-mg groups, respectively, and the adverse events were not dose dependent. A blood cholesterol increase was observed in 44.0% of the patients. Liver function disorders and decreases in white blood cell counts were also observed, but these were mild and transient. There was no increase in antinuclear antibodies or anti-DNA antibodies. Anti-MRA antibodies were detected in 2 patients.

CONCLUSION

Treatment with MRA was generally well tolerated and significantly reduced the disease activity of RA.

Enhanced production of osteopontin in multiple myeloma: clinical and pathogenic implications

In this study, we examined osteopontin (OPN) production in myeloma cells and plasma OPN levels in multiple myeloma (MM) patients. We assessed OPN production in bone marrow cells (BMCs) by immunocytochemistry and enzyme-linked immunosorbent assay (ELISA). We also assessed OPN production in various B-cell malignant cell lines, including three myeloma cell lines by reverse transcription polymerase chain reaction (RT-PCR) and Western blotting. In addition, we measured plasma OPN concentrations by ELISA in 30 MM patients, 21 monoclonal gammopathy of undetermined significance (MGUS) patients and 30 healthy volunteers. As a result, in an immunocytochemical study, abundant OPN was detected in BMCs from overt MM patients, whereas no OPN was detected in BMCs from patients with other haematological diseases, including MGUS. Cultured BMCs from overt MM patients produced more OPN than those from patients with either smouldering MM or MGUS. Myeloma cell lines spontaneously produced OPN. Plasma OPN levels of MM patients were significantly higher than those of MGUS patients and healthy volunteers (P < 0.05). Moreover, they correlated with both progression and bone destruction of the disease (P < 0.05). These suggest that myeloma cells actively produce OPN, which possibly contributes to osteoclastic bone resorption in MM. Plasma OPN levels may be a useful biomarker for assessing bone destruction in MM and distinguishing MM from MGUS or smouldering MM.

Determination of conditions for the production scale sterilization of prefilled syringes

External and internal differences in pressure of prefilled syringes can cause plunger movement during sterilization, which might cause drug product contamination. Consequently the pressure inside the autoclave during sterilization should be controlled carefully to prevent contamination of the drug product by microorganism and particulates. A previously determined theoretical relationship of temperature to pressure in sealed bottles was modified for prefilled syringes to take plunger movement into account. This modification yielded a correction factor that includes a coefficient of linear thermal expansion for the syringe, thermal expansion of the plunger, and friction between the plunger and the syringe wall. To confirm the accuracy of this modified relationship, 100 mL polypropylene prefilled syringes with butyl rubber plungers, some of which carried pressure and temperature sensors, were used to test various sterilization conditions at the experimental scale. The results showed that the major problem in establishing the pressure conditions for production scale sterilization is temperature distribution throughout the load. However, an over pressure sterilization cycle at 121 degrees C and 0.34 MPa showed the best results. Microbial challenge and light-obscuration particle count tests were performed on the syringes from the worst-case location predicted from modified relationship; the results show that these conditions preserved the sterility of the drug product and protected it from particulate contamination.

Toxicity, pharmacokinetics, and dose-finding study of repetitive treatment with the humanized anti-interleukin 6 receptor antibody MRA in rheumatoid arthritis. Phase I/II clinical study

OBJECTIVE

To evaluate the safety and pharmacokinetics of multiple infusions of a humanized anti-interleukin-6 (IL-6) receptor antibody, MRA, in patients with rheumatoid arthritis (RA).

METHODS

In an open label trial, 15 patients with active RA were intravenously administered 3 doses (2, 4, or 8 mg/kg) of MRA biweekly for 6 weeks, and pharmacokinetics were assessed. Patients continued on MRA treatment for 24 weeks, and were then assessed for safety and efficacy.

RESULTS

The treatment was well tolerated at all doses with no severe adverse event. Increased total serum cholesterol was detected as an MRA related reaction in 10/15 (66%) patients. There was no statistically significant difference in the frequency of adverse events among the 3 dose groups. There were no new observations of antinuclear antibody or anti-DNA antibody, and no anti-MRA antibody was detected. The T1/2 increased with repeated doses and as the dose increased. T1/2 after the 3rd dose of 8 mg/kg reached 241.8 +/- 71.4 h. In 12/15 (80%) patients whose serum MRA was detectable during the treatment period, objective inflammatory indicators such as C-reactive protein, erythrocyte sedimentation rate, and serum amyloid A were completely normalized at 6 weeks, although there was no statistically significant difference in efficacy among the 3 dose groups. Nine of 15 patients achieved ACR 20 at 6 weeks. At 24 weeks, 13 patients achieved ACR 20 and 5 achieved ACR 50.

CONCLUSION

Repetitive treatment with MRA was safe and normalized acute phase response in patients with RA. Optimal dosing schedule was not defined in this small study, but maintenance of serum MRA concentration seemed important to achieve efficacy.

Prediction of lymph node metastasis by p53, p21(Waf1), and PCNA expression in esophageal cancer patients

Esophageal cancer is still one of the most widespread diseases, and surgery for esophageal carcinoma is very stressful for patients. Even though lymph node metastasis occurs more frequently in cases of early esophageal cancer than it does in cases of gastric cancer, surgeons prefer to avoid lymph node dissection if possible, thereby subjecting patients to less invasion. Thus, the aim of the present study was to examine the possibility of predicting lymph node metastasis on the basis of tumor location, quantification theory II analysis of tumor expression of genetic markers in primary esophageal cancer. Surgical specimens from 63 patients of esophageal cancer with submucosal invasion were examined for the relationship between tumor location and lymph node metastasis. In 19 of these 63 patients, p53, p21(Waf1, and proliferating cell nuclear antigen (PCNA) were examined immunohistologically, and to quantify the risk of lymph node metastasis, computer analysis was performed on the basis of quantification theory II, in which pathological lymph node metastasis (pN) was the objective variable and "high" or "low" expression of each of the three markers was the predictive variable. Tumors located in the lower third of the esophagus had no lymph node metastasis to the upper mediastinal region, and were thus indicated for trans-hiatal esophagectomy. A coefficient greater than 0.91 predicted node negative disease accurately without false-negative results; false-positive results were obtained for 54.5% of patients with a coefficient less than 0.064. Thus, we found that quantification theory II may be useful when considering indications for surgery without lymph node dissection in some cases of T1 esophageal carcinoma.

Anti-interleukin-6 receptor antibody therapy reduces vascular endothelial growth factor production in rheumatoid arthritis

OBJECTIVE

To investigate whether interleukin-6 (IL-6) is a regulator of vascular endothelial growth factor (VEGF) in rheumatoid arthritis (RA).

METHODS

Serum VEGF levels in RA patients were assayed before and after 8 weeks or 24 weeks of maintenance therapy with humanized anti-IL-6 receptor monoclonal antibody (anti-IL-6R mAb). VEGF secreted by RA synovial fibroblasts cultured in the presence of IL-6, IL-1beta, and/or tumor necrosis factor alpha (TNFalpha) was measured. The inhibitory effect of anti-IL-6R mAb, recombinant IL-1 receptor antagonist (IL-1Ra), and anti-TNFalpha mAb on VEGF production was also examined.

RESULTS

Serum VEGF levels in RA patients before anti-IL-6R mAb therapy were significantly higher than those in healthy controls (P < 0.0005). Treatment of RA patients with anti-IL-6R mAb normalized serum VEGF levels. In the in vitro study, IL-6 and IL-1beta each induced a slight amount of VEGF production in synovial cells, but TNFalpha did not. Although VEGF-inducing activity of these cytokines was not remarkable when they were added alone, IL-6 acted synergistically with IL-1beta or TNFalpha to induce VEGF production. There was no synergistic effect between IL-1beta and TNFalpha. In the presence of all of these cytokines, anti-IL-6R mAb eliminated the synergistic effect of IL-6, IL-1beta, and TNFalpha, while IL-1Ra or anti-TNFalpha mAb did not.

CONCLUSION

Anti-IL-6R mAb therapy reduced VEGF production in RA. IL-6 is the pivotal cytokine that induces VEGF production in synergy with IL-1beta or TNFalpha, and this may be the mechanism by which IL-6 blockade effectively suppresses VEGF production in synovial fibroblasts.

Sustained interleukin-6 signalling leads to the development of lymphoid organ-like structures in the lung

A variety of pathological changes are seen in lymphoproliferative disorders of the lung but the histogenesis of these abnormalities is not yet fully understood. We previously showed that adenovirus vector-mediated transient expression of both the human interleukin-6 (IL-6) and IL-6 receptor (IL-6R) genes, but not the IL-6 gene alone, in the rat lung induced lymphocytic alveolitis. In the present study, we explored the lung pathology of human IL-6 and IL-6R double transgenic mice to elucidate the effects of prolonged IL-6 signalling on the lung. The transgenic animals developed mononuclear cell accumulation in peribronchovascular regions, but little infiltration into alveolar spaces. Immunohistochemical analysis revealed that the cellular accumulations contained not only mixtures of inflammatory cells but also lymphoid tissue-like structures. As the expression of CXCL13/BLC, the indispensable chemokine for lymphoid organogenesis, was recognized in the B cell follicles of the pulmonary lesions, we speculate that this chemokine plays an inductive role in the development of the lymphoid tissue-like structures. These structures were distinguished from bronchus-associated lymphoid tissues (BALTs) by their location and by the lack of lymphoepithelium, which is a characteristic of BALT. These findings imply that IL-6 signalling may play a role in the pathogenesis of lymphoproliferative disorders of the lung.

Anti-interleukin 6 (IL-6) receptor antibody suppresses Castleman's disease like symptoms emerged in IL-6 transgenic mice

Transgenic mice carrying human IL-6 cDNA fused with a murine major histocompatibility class-I promoter (H-2L(d)) were serially administered with anti-interleukin-6 receptor (IL-6R) monoclonal antibody (mAb), MR16-1, from the age of 4 weeks to estimate its efficacy on a variety of disorders developed in these mice, most of which are similar to the disorders associated with Castleman's disease. In the control mice treated with isotype-matched mAb, a massive and multiple IgG1 plasmacytosis, mesangial proliferative glomerulonephritis, leukocytosis, thrombocytosis, anemia and abnormalities of blood chemical parameters have developed in accordance with the elevation of serum IL-6, and 50% of mice have died of renal failure by 18 weeks of age. In contrast, the treatment with MR16-1 prevented all these symptoms and prolonged the lifetime of the majority of the mice. Thus, the constitutive overexpression of IL-6 caused various disorders, and the treatment with anti-IL-6R mAb completely prevented from these symptoms. These results clearly confirm that IL-6 indeed plays an essential role in the pathogenesis of a variety of disorders. Furthermore, anti-IL-6R mAb could provide novel therapy for Castleman's disease and MR16-1 should be a useful tool to estimate therapeutic potential of IL-6 antagonists in a variety of murine models for human disease.

Characterization of anti-mouse interleukin-6 receptor antibody

Hybridoma that produces rat anti-mouse interleukin 6 receptor (IL-6R) antibody, MR16-1, was established by the fusion of mouse P3U1 myeloma cells and spleen cells from mouse soluble IL-6R (sIL-6R)-immunized Wistar rat. In the present study, we examined the characteristics of MR16-1 in vitro and in vivo. MR16-1 bound to mouse sIL-6R dose-dependently. MR16-1 suppressed IL-6-induced proliferation of 7TD1 cells in a dose-dependent manner and this inhibitory effect was reversed by the addition of a higher concentration of IL-6. Cross-reactivity study using T cells from mouse, rat, and human revealed that MR16-1 did not cross-react with human and rat IL-6R. Binding region analysis using several human-mouse chimeric IL-6Rs showed that half of the fibronectin domain II of mouse IL-6R (amino acids 214-285) was required for MR16-1 binding. Furthermore, MR16-1 completely suppressed IL-6-induced antibody production in DNP-KLH immunized mice. These lines of evidence demonstrate that MR16-1 is useful to investigate the physiological and pathological roles of IL-6 and sIL-6R in mice.

Influences of anti-mouse interleukin-6 receptor antibody on immune responses in mice

In the present study, we examined the effect of anti-IL-6 receptor antibody (MR16-1) on humoral and cellular immune responses in mice. MR16-1 did not affect antigen-specific antibody production in either the primary or secondary response in mice immunized with dinitro-phenyl (DNP)-keyhole limpet haemocyanin (KLH) in saline. DNP-KLH immunization with complete Freund's adjuvant (CFA) markedly augmented anti-DNP antibody production and induced interleukin 6 (IL-6) production in serum. In this case, MR16-1 significantly suppressed antibody production and further increased serum IL-6 levels. Regarding the cellular response, we studied the effect on the delayed-type hypersensitivity (DTH) response. DTH response was induced in mice by the immunization with Mycobacterium butyricum with incomplete Freund's adjuvant and following antigen challenge into the footpad 14 days after immunization. When MR16-1 was injected immediately after immunization, the DTH response was significantly suppressed and enlargement of the spleen was also suppressed. This suppressive effect was observed, when MR16-1 was administered on day 0, but not on days 5 and 10. Again, serum IL-6 levels were much higher in MR16-1-treated mice compared with controls. Furthermore, spleen cells from control mice released IL-2 and INFgamma by the stimulation of antigen in vitro. In contrast, spleen cells from MR16-1-treated mice produced these cytokines at a marginal level. In contrast, MR16-1 did not suppress the DTH response, when it was injected immediately after antigen challenge. Our results suggest that IL-6 does not always involve antibody production, although IL-6 augments antibody production, and that IL-6 is essential for the induction of Th1 cells.

Therapeutic benefit of blocking interleukin-6 activity with an anti-interleukin-6 receptor monoclonal antibody in rheumatoid arthritis: a randomized, double-blind, placebo-controlled, dose-escalation trial

OBJECTIVE

To investigate the safety and efficacy of MRA, a recombinant human anti-interleukin-6 (anti-IL-6) receptor monoclonal antibody of the IgG1 subclass that inhibits the function of IL-6, in patients with established rheumatoid arthritis (RA).

METHODS

A randomized, double-blind, placebo-controlled, dose-escalation trial was conducted in 45 patients with active RA, as defined by the American College of Rheumatology (ACR) revised criteria. Patients were sequentially allocated to receive a single intravenous dose of either 0.1, 1, 5, or 10 mg/kg of MRA or placebo. The primary efficacy end point was meeting the ACR 20% response criteria at week 2 after treatment.

RESULTS

Demographic features were similar between treatment groups. At week 2, a significant treatment difference was observed between the 5 mg/kg of MRA and placebo, with 5 patients (55.6%) in the MRA cohort and none in the placebo cohort achieving ACR 20% improvement. There was no statistically significant difference in the ACR 20% response between the other 3 MRA cohorts and placebo at week 2. The mean disease activity score at week 2 in those who received 5 mg/kg and 10 mg/kg of MRA was 4.8 and 4.7 (P < 0.001 and P < 0.001 by analysis of variance), respectively. These mean scores were statistically significantly lower than those in the 0.1- and 1-mg/kg MRA and the placebo cohorts (6.4, 6.2, and 7.0, respectively). The erythrocyte sedimentation rate and C-reactive protein values fell significantly in the 5- and 10-mg/kg MRA cohorts and normalized 2 weeks after treatment. Seventeen patients (5, 4, 6, 2, and 0 patients in the placebo, 0.1-, 1-, 5-, and 10-mg/kg MRA cohorts, respectively) required corticosteroid or disease-modifying antirheumatic drug treatment because of active disease before study end. They were regarded as nonresponders from the time they received these treatments. Diarrhea was the most common adverse event, occurring in 8% of patients. Seven patients (15.6%) reported a severe adverse event (3, 1, 2, and 2 patients in the placebo, 0.1-, 1-, and 10-mg/kg MRA cohorts). There were no serious adverse events that were thought to be related to the study drug.

CONCLUSION

This is the first randomized controlled trial showing that inhibition of IL-6 significantly improved the signs and symptoms of RA and normalized the acute-phase reactants. Further research with multiple dosing is necessary to define the most appropriate therapeutic regimen of MRA in RA.

[A humanized anti-IL-6 receptor antibody(MRA) in RA therapy]

Hyperproduction of Interleukin-6(IL-6) is observed in the rheumatoid arthritis(RA) patients and serum level of IL-6 is closely related to disease activity. IL-6 is a pleiotropic cytokine and its hyperfunctions explain most of the clinical symptoms in RA. Since MRA is humanized antibody from a mouse anti-human IL-6 receptor antibody, MRA can be administered repeatedly because of its low antigenesity to human. MRA inhibits IL-6 function by the blocking IL-6 binding to IL-6 receptor, resulting the prevention of development on collagen inducing arthritis(CIA) in cynomolgus monkeys whose IL-6R is cross-reacted with MRA. These evidence suggest that MRA has anti-arthritic effects. Clinical trials of MRA for RA patients have already started, and MRA therapy is effective as well as anti-TNF alpha and anti-IL-1 therapies.

Comparison of the Rear Impact Biofidelity of BioRID II and RID2

Researchers worldwide try to define a unique test procedure for the assessment of whiplash protection of seats and restraint systems in low speed rear-end impact. Apart from valid injury criteria and uniform crash conditions, there is no clear answer to the question, which dummy to use. There are two impact dummies currently available, which have been designed for rear-end impact testing: BioRID and RID2. Both dummies have been evaluated in several test programs, however, both dummies have never been compared with each other in the test conditions, which form the basis of their design. BioRID was based on and validated against volunteer tests performed by Davidsson and Ono, while RID2 was designed with and validated against PMHS tests done by Bertholon and compared to volunteer tests reported by Van den Kroonenberg. This paper compares the responses of both rear impact dummies and the Hybrid III for the test conditions mentioned above. The setup of Davidsson used a rigid seat with flexible back and head restraint panels, while the setups from Ono and Bertholon used a rigid seat without a head restraint, in spite of being not representative for real car seats. This configuration creates a well defined test environment which will not affect nor obscure the dummy response Results of the performance of both rear impact dummies and the Hybrid III in comparison to the human responses will be presented in this paper. The results show that both rear impact dummies are capable of simulating rear impact responses, especially the head-neck kinematics. A difference in load pattern was found, which could be relevant when injury criteria will be based on neck forces and/or torques. Moreover, the dummies show a different interaction with the seat back, illustrated by the differences in T1 kinematics: BioRID shows larger T1 rotation and more ramping up than RID2, while spine straightening is comparable for both dummies. The current study showed good scores for both dummies in the setup on which they are based. The biofidelity score of BioRID is slightly better than for RID2, while the performance of the Hybrid III is relatively poor. However, repeatability, reproducibility and handling are not part of the evaluation, even though they are important for the practical use of the dummies.

Human interleukin-6 induces human herpesvirus-8 replication in a body cavity-based lymphoma cell line

Human herpesvirus-8 (HHV-8) is etiologically associated with Kaposi's sarcoma (KS), body cavity-based lymphoma (BCBL), and multicentric Castleman's disease (MCD). These HHV-8-associated diseases arise predominantly in acquired immunodeficiency syndrome (AIDS) patients. Human interleukin-6 (huIL-6) elevated in the serum of AIDS patients is suggested to stimulate the growth of KS and BCBL and to augment the symptoms of MCD. To determine whether huIL-6 stimulates HHV-8 replication directly, expression of the HHV-8 ORF-50 immediate-early gene (transcription activator) and ORF-26 late lytic gene (a capsid protein) was assessed in a BCBL-1 cell line stimulated by huIL-6 by means of real-time reverse transcription-polymerase chain reaction. huIL-6 induced both ORF-50 and ORF-26 expression, and the maximal ORF-50 expression appeared earlier than that of ORF-26. The data indicate that huIL-6 reactivates HHV-8 in BCBL-1 cells through inducing ORF-50. We also confirmed the previously reported activities of HHV-8-encoded huIL-6 homologue (viral interleukin-6 [vIL-6]) on human immunodeficiency virus (HIV) replication in U1 cell line and huIL-6 production by MT-4 T cells, and utilizing monoclonal antibodies to the huIL-6 receptor components, we elucidated that gp130 is the signaling molecule necessary for these vIL-6 activities. These data suggest the possible existence of interaction between HIV and HHV-8 via IL-6, and that the blockade of IL-6 signal by anti-IL-6R antibody or anti-gp130 antibody can constitute a strategy to treat HIV/HHV-8 dually infected patients.

The paradigm of IL-6: from basic science to medicine

IL-6 is a pleiotropic cytokine with a wide range of biological activities in immune regulation, hematopoiesis, inflammation, and oncogenesis. Its activities are shared by IL-6-related cytokines such as leukemia inhibitory factor and oncostatin M. The pleiotropy and redundancy of IL-6 functions have been identified by using a unique receptor system comprising two functional proteins: an IL-6 receptor (IL-6R) and gp130, the common signal transducer of cytokines related to IL-6. Signal transduction through gp130 is mediated by two pathways: the JAK-STAT (Janus family tyrosine kinase-signal transducer and activator of transcription) pathway and the Ras mitogen-activated protein kinase pathway. The negative regulators of IL-6 signaling have also been identified, although the physiological roles of the molecules are not yet fully understood. The pathological roles of IL-6 have also been clarified in various disease conditions, such as inflammatory, autoimmune, and malignant diseases. On the basis of the findings, a new therapeutic approach to block the IL-6 signal using humanized anti-IL-6R antibody for rheumatoid arthritis, Castleman's disease, and multiple myeloma has been attempted.

[A new therapeutic approach to advanced and recurrent gastric cancer by TS-1]

In the present study, we demonstrate the treatment results of TS-1 on 22 gastric carcinoma patients (15 far advanced and 7 recurrent patients) from June 1999 to December 2000. TS-1 was administered at 75 mg/m2/day, twice daily per body for 28 days followed by a 14-day interval (1 cycle). Successful treatment was obtained in from 1 to 11 cycles, and we obtained 9 (47.4%) partial responses (PR), 7 stable disease (NC) and progressive disease (PD) among 19 evaluable patients. PR was obtained in 7 (58.3%) out of 12 primary lesions of the stomach. We also obtained 1 CR of liver metastasis and 4 PR of 9 distant lymph node metastases (44.4%). Moreover, malignant ascites disappeared in 4 (57.1%) out of 7 cases and PR was obtained in 3 (50%) out of 6 measurable cases of peritoneal disease. In addition, two patients had hydronephrosis which improved after 1 cycle of TS-1 treatment. The adverse effects observed were grade 3 bone marrow suppression in three cases, severe diarrhea in one case, one case of liver dysfunction and a few cases of nausea and vomiting. These results indicate that the oral tegafur compound, TS-1, is a new therapeutic tools for advanced and recurrent gastric carcinomas, especially peritoneal disease.

An analysis of relapsed breast cancer in patients previously treated with breast conserving surgery

BACKGROUND

Recent advances in breast surgery have focused on breast conserving surgery in combination with radiotherapy. In the present study, we examine by retrospective analysis 105 patients with breast cancer who received breast conserving surgery for factors influencing disease free survival.

METHODS

The analysis was performed on 105 patients with breast cancer who received breast conserving surgery in our department, including 38 patients without radiotherapy and 67 patients treated with radiotherapy. The disease-free survival of the patients was analyzed using the Kaplan-Meier method. The relapsed patients were assessed by examining pathological features and gene expression by immunohistochemical staining.

RESULTS

There was no significant difference in the disease free survival at 5 years between patients without radiotherapy (89.6%) and with radiotherapy (94.5%). Relapse after breast conserving surgery was found in 6 patients including 4 patients without radiotherapy and 2 patients with radiotherapy. Local relapse and bone metastasis were found in 4 (3.8%) and 2 patients, respectively. Among the 4 local relapses, 1 patient had received radiotherapy and 3 patients had not. There was no significant difference between the type of relapse in terms of lymph node metastasis, hormone receptor, nuclear grade and intraductal component, but more vessel invasion was observed in the 2 cases with bone metastasis. The overexpression of apoptosis and angiogenesis genes such as p53, Bax, Bcl-XL, Bcl-2 and VEGF was not common in the relapsed patients, whereas the overexpression of drug resistance genes, either P-gp or MRP1, was found in the all patients.

CONCLUSIONS

Although radiotherapy may reduce the incidence of local relapse and increase disease free survival after breast conserving surgery, the development of an effective adjuvant chemotherapy based on drug resistance markers, is also required.

Characterization of the human Fc gamma RIIB gene promoter: human zinc-finger proteins (ZNF140 and ZNF91) that bind to different regions function as transcription repressors

Expression of the human low-affinity Fc receptors for IgG (human Fc gamma RII) is differentially regulated. We report here the characterization of the promoter structure of the human Fc gamma RIIB gene and the isolation of the promoter region-binding proteins by a yeast one-hybrid assay. The minimal 154-bp region upstream from the transcription start site of the human Fc gamma RIIB gene was shown to possess promoter activity in a variety of cells. An electrophoretic mobility shift assay indicated that multiple nuclear factors in cell extracts bind to the two regions [F2-3 (-110 to -93) and F4-3 (-47 to -31)] of the human Fc gamma RIIB gene promoter. Mutation analysis indicated that GGGAGGAGC (-105 to -97) and AATTTGTTTGCC (-47 to -36) sequences are responsible for binding to nuclear factors respectively. By using GGGAGGAGC and AATTTGTTTGCC as bait sequences, we cloned two zinc-finger proteins (ZNF140 and ZNF91) that bind to the F2-3 and F4-3 regions within the promoter of the human Fc gamma RIIB gene respectively. When the ZNF140 and ZNF91 were transfected with reporter plasmid, both showed repressor activity with additive effects. Thus, these results indicate that these cloned ZNF140 and ZNF91 proteins function as repressors for the human Fc gamma RIIB transcription.

Significance of lymph node dissection of the superior mediastinal region in esophageal cancer patients

The effect of the superior mediastinal lymph node dissection was compared retrospectively with that of standard dissection in 108 esophageal cancer patients. Five-year survival rates were 46.3% in patients who underwent standard surgery (group A) and 39.3% in patients who underwent superior mediastinal lymph node dissection (group B). The survival curves were basically the same. Nineteen out of 42 (45.2%) tumors in group A and 24 out of 66 (36.4%) tumors in group B recurred. The distribution of the first sites of recurrence did not differ significantly between groups. However, 14 tumors (67%) in group A recurred in the lymph nodes, but only seven tumors recurred (28%) in the lymph nodes in group B. Eleven tumors (52%) in group A recurred to superior mediastinal nodes, but only one tumor (4%) recurred to a superior mediastinal node in group B. Fourteen of the group B patients showed metastasis to superior mediastinal lymph nodes and none of these patients survived for more than 5 years. Eleven of these 14 patients showed metastasis to only one or two nodes. Based on our data and other reported findings, we conclude that extended lymphadenectomy of the superior mediastinal region alone does not contribute to improved survival of esophageal cancer patients, but it does contribute to the prevention of lymph node recurrence in this region.

Humanized antibody to human interleukin-6 receptor inhibits the development of collagen arthritis in cynomolgus monkeys

In the present study, we demonstrated the anti-arthritic effect of humanized anti-human IL-6 receptor (IL-6R) antibody, MRA, in cynomolgus monkey. MRA can react with monkey IL-6R and block signal transduction of IL-6. Collagen-induced arthritis (CIA) was induced by twice immunizing with bovine type II collagen (CII) emulsified with complete adjuvant. MRA was intravenously injected once a week, from the day of the first collagen immunization, for 13 weeks. The symptoms of arthritis were evaluated using a visual scoring system and radiography. Inflammatory parameters (C-reactive protein (CRP), fibrinogen, and erythrocyte sedimentation rate (ESR) and concentrations of anti-CII antibody, anti-MRA antibody, and MRA were monitored regularly. At the end of the study, histological evaluation was carried out. MRA, at a dose of 10 mg/kg, gave rise to statistically significant suppression. The elevation of serum CRP and fibrinogen levels and ESR were also inhibited. Furthermore, radiographic and histological examination showed that MRA treatment suppressed joint destruction. Our results demonstrate that IL-6 plays an important role in monkey CIA and that MRA may be an attractive agent for the treatment of rheumatoid arthritis.

Enhancement of antitumor effect by intratumoral administration of bax gene in combination with anticancer drugs in gastric cancer

Proapototic gene is an important target to enhance the chemotherapeutic effect in cancer cells. Based on in vitro study showing that the introduction of bax gene enhanced the sensitivity to anticancer drugs, we examined whether the intratumoral administration of bax gene could enhance the anti-tumor effect in combination with anticancer drugs in gastric cancer. The human gastric cancer cell line, MKN45 was transplanted into nude mice, and the intratumoral administration of bax gene was performed using the bax cDNA plasmid complexed with a cationic lipopolyamine. The enhancement of antitumor effect was examined in the combination with 5-fluorouracil (5-FU) and cisplatin (CDDP). The anticancer drugs were administered intraperitoneally with one third of LD50 four times at 4-day intervals, and the antitumor effect was assessed by the NCI protocol. The expression of bax gene was analyzed by RT-PCR and the apoptotic cell death was assessed by TUNEL method. The intratumoral administration of bax gene alone showed slight anti-tumor effect as compared to that of control tumor injected with vector alone. The antitumor effect of 5-FU and CDDP was significantly enhanced in the combination with intra-tumoral administration of bax gene as compared to that of CDDP and 5-FU alone (p<0.05, Student's t-test). The enhancement of antitumor effect was associated with the constitutive overexpression of bax gene and with the induction of apoptosis in the tumor treated with anticancer drug and bax gene. These results indicate that the combination therapy of intratumoral administration of bax gene complexed with a cationic lipopolyamine and anticancer drugs may provide us a new strategy for cancer chemotherapy to enhance its therapeutic efficacy in gastric cancer as termed with gene-chemotherapy.

An analysis of the therapeutic efficacy of protracted infusion of low-dose 5-fluorouracil and cisplatin in advanced gastric cancer

To analyze the clinical efficacy of a protracted infusion of low-dose 5-fluorouracil (5-FU) and cisplatin (CDDP), a phase II study was performed in 36 patients with advanced gastric cancer. The treatment schedule of the low-dose administration of 5-FU and CDDP (FP) was a continuous infusion of 5-FU (250 mg/m2) for 28 consecutive days and a drip infusion of CDDP (3.5 mg/m2) for 5 consecutive days, followed by a 2-day interval each week in one cycle. The overall response rate was 47.2%. Of importance, the improvement in quality of life assessed by performance status (PS) and oral intake was 13.9% and 33.3%, respectively. The toxicity in low-dose FP treatment was less than grade 2, including gastrointestinal toxicities and bone marrow suppression, and this was tolerable during the treatment. The median survival time (MST) and 1-year survival rate were 8 months and 36.2%, respectively. In a pharmacokinetic analysis following the protracted infusion of low-dose FP, the plasma concentrations of 5-FU and CDDP were increased to about 120-130 ng/ml and 0.3-0.5 microg/ml on day 21 after the treatment, respectively. The plasma concentrations of 5-FU and CDDP were not significantly different between responders and non-responders. The tumor response to low-dose FP treatment was associated with the induction of apoptotic cell death and with the overexpression of apoptosis-related genes, such as Bax and Bcl-Xs, in cancer cells. These results indicate that the protracted infusion of low-dose FP could be a useful regimen for patients with advanced gastric cancer, in terms of the high response rate and low toxicity, possibly leading to the prolongation of survival and improvement in the quality of life.

Anti-interleukin 6 receptor antibody treatment in rheumatic disease

Interleukin 6 (IL6) is a pleiotropic cytokine with a wide range of biological activities. IL6 transgene into mice gives rise to the abnormalities such as hypergammaglobulinaemia, thrombocytosis, infiltration of inflammatory cells into the tissues, mesangial cell proliferation of the kidney as well as splenomegaly and lymphadenopathy, which are predictable by the biological functions of IL6 shown in vitro. Continuous overproduction of IL6 is observed in patients with some immune-inflammatory diseases such as Castleman's disease and rheumatoid arthritis that are frequently associated with similar abnormalities to those of IL6 transgenic mice, strongly suggesting the involvement of IL6 in the human diseases. Successful treatment of the model animals for immune-inflammatory diseases with anti-IL6 receptor (IL6R) antibody thus indicates the possible application of IL6 blocking agents to treat the IL6 related immune-inflammatory diseases of humans. In this review, the new therapeutic strategy for Castleman's disease and RA using humanized antibody to human IL6 receptor, MRA, is discussed.

Human herpesvirus 8-encoded interleukin-6 homologue (viral IL-6) induces endogenous human IL-6 secretion

We found that human herpesvirus 8-encoded IL-6 (vIL-6) induced endogenous human IL-6 (huIL-6) secretion from various cell lines (MT-4, THP-1, U937, Raji, and CESS) including patients with multicentric Castleman's disease. Especially, in MT-4 cells, huIL-6 was enhanced with vIL-6 by 30-fold compared with that of control. In addition, reverse transcriptase-polymerase chain reaction confirmed that vIL-6 induced huIL-6 expression in MT-4 cells. Our novel finding of the huIL-6 induction by vIL-6 indicates that vIL-6 may play a significant role in the pathogenesis of HHV-8 associated diseases.

Human herpesvirus 8-encoded interleukin-6 homologue (viral IL-6) induces endogenous human IL-6 secretion

We found that human herpesvirus 8-encoded IL-6 (vIL-6) induced endogenous human IL-6 (huIL-6) secretion from various cell lines (MT-4, THP-1, U937, Raji, and CESS) including patients with multicentric Castleman's disease. Especially, in MT-4 cells, huIL-6 was enhanced with vIL-6 by 30-fold compared with that of control. In addition, reverse transcriptase-polymerase chain reaction confirmed that vIL-6 induced huIL-6 expression in MT-4 cells. Our novel finding of the huIL-6 induction by vIL-6 indicates that vIL-6 may play a significant role in the pathogenesis of HHV-8 associated diseases.

[The clinical effect of low-dose FP (5-FU + low-dose CDDP) in patients with far advanced gastric cancer, and their quality of life]

Low-dose FP therapy was carried out in 30 patients with far advanced gastric cancer and assessed according to anti-tumor effect and quality of life (QOL). This therapy consisted of CDDP (3.5-7 mg/m2/day infused on Days 1-5 every week) and continuous infusion of 5-FU (250 mg/m2/day for 28 days). A partial response was observed in 15 cases, so the overall response rate was 50%. The response rates with stomach and lymph node cancers were higher than those of other organs (64.3% and 55.6%). Patients without peritoneal dissemination, with good performance status (PS) (0, 1) and differentiated histologic type showed a significantly higher response rate than patients with peritoneal dissemination, poor PS (2, 3, 4) and undifferentiated histologic type (p = 0.0034, 0.0253, 0.0080). No side effects (> or = WHO grade 3) were observed. The QOL of patients was assessed according to the percentage of patients with an observed improvement of diet, who could be discharged from hospital, and the duration in hospitals in relation to survival time (hospital stay). The QOL of patients with low-dose FP therapy was better than that of patients with usual combination chemotherapy. Low-dose FP therapy is a promising regimen for patients with far advanced gastric cancer.

Blockade of interleukin 6 trans signaling suppresses T-cell resistance against apoptosis in chronic intestinal inflammation: evidence in crohn disease and experimental colitis in vivo

The pro-inflammatory cytokine interleukin (IL)-6 (refs. 1-5) can bind to cells lacking the IL-6 receptor (IL-6R) when it forms a complex with the soluble IL-6R (sIL-6R) (trans signaling). Here, we have assessed the contribution of this system to the increased resistance of mucosal T cells against apoptosis in Crohn disease (CD), a chronic inflammatory disease of the gastrointestinal tract. A neutralizing antibody against IL-6R suppressed established experimental colitis in various animal models of CD mediated by type 1 T-helper cells, by inducing apoptosis of lamina propria T cells. Similarly, specific neutralization of sIL-6R in vivo by a newly designed gp130-Fc fusion protein caused suppression of colitis activity and induction of apoptosis, indicating that sIL-6R prevents mucosal T-cell apoptosis. In patients with CD, mucosal T cells showed strong evidence for IL-6 trans signaling, with activation of signal transducer and activator of transcription 3, bcl-2 and bcl-xl. Blockade of IL-6 trans signaling caused T-cell apoptosis, indicating that the IL-6-sIL-6R system mediates the resistance of T cells to apoptosis in CD. These data indicate that a pathway of T-cell activation driven by IL-6-sIL-6R contributes to the perpetuation of chronic intestinal inflammation. Specific targeting of this pathway may be a promising new approach for the treatment of CD.

IL-6 inhibits the proliferation of fibroblastic synovial cells from rheumatoid arthritis patients in the presence of soluble IL-6 receptor

IL-6 and tumor necrosis factor (TNF)-alpha have been proven to play an important role in the development of rheumatoid arthritis (RA). It is well known that TNF-alpha induces IL-6 production from synovial cells as well as their proliferation. The effect of IL-6 on synovial cells, however, is not clear. An in vitrostudy was performed to determine the effect of IL-6 on the proliferation of synovial cells. Fibroblastic synovial cells isolated from the synovial tissues of eight RA patients were employed after the third to sixth passages. IL-6 in the presence of soluble IL-6 receptor (sIL-6R) inhibited the proliferation of synovial cells in a dose-dependent manner in seven cases without increasing the number of necrotic or apoptotic cells, while TNF-alpha increased synovial cell proliferation in all cases. The inhibitory effect of IL-6 was observed only in the presence of sIL-6R although small amounts of IL-6R were detected in these cells by RT-PCR analysis. However, anti-IL-6R or anti-gp130 mAb treatment increased spontaneous growth of synovial cells in all eight cases, suggesting that endogenous IL-6 and a small amount of IL-6R expressed in synovial cells suppressed their growth without exogenous IL-6 or sIL-6R. In addition, the IL-6-sIL-6R complex reduced the TNF-alpha-induced proliferation of synovial cells while TNF-alpha induced their IL-6 production. These data suggest that IL-6 may act as a negative feedback factor for TNF-alpha-induced synovial cell growth.

Improvement in Castleman's disease by humanized anti-interleukin-6 receptor antibody therapy

Castleman's disease, an atypical lymphoproliferative disorder, can be classified into 2 types: hyaline-vascular and plasma cell types according to the histologic features of the affected lymph nodes. The plasma cell type is frequently associated with systemic manifestations and is often refractory to systemic therapy including corticosteroids and chemotherapy, particularly in multicentric form. Dysregulated overproduction of interleukin-6 (IL-6) from affected lymph nodes is thought to be responsible for the systemic manifestations of this disease. Therefore, interference with IL-6 signal transduction may constitute a new therapeutic strategy for this disease. We used humanized anti-IL-6 receptor antibody (rhPM-1) to treat 7 patients with multicentric plasma cell or mixed type Castleman's disease. All patients had systemic manifestations including secondary amyloidosis in 3. With the approval of our institution's ethics committee and the consent of the patients, they were treated with 50 to 100 mg rhPM-1 either once or twice weekly. Immediately after administration of rhPM-1, fever and fatigue disappeared, and anemia as well as serum levels of C-reactive protein (CRP), fibrinogen, and albumin started to improve. After 3 months of treatment, hypergammaglobulinemia and lymphadenopathy were remarkably alleviated, as were renal function abnormalities in patients with amyloidosis. Treatment was well tolerated with only transient leukopenia. Histopathologic examination revealed reduced follicular hyperplasia and vascularity after rhPM-1 treatment. The pathophysiologic significance of IL-6 in Castleman's disease was thus confirmed, and blockade of the IL-6 signal by rhPM-1 is thought to have potential as a new therapy based on the pathophysiologic mechanism of multicentric Castleman's disease. (Blood. 2000;95:56-61)

Degenerate MAGGY elements in a subgroup of Pyricularia grisea: a possible example of successful capture of a genetic invader by a fungal genome

The LTR-retrotransposon MAGGY is found sporadically in isolates of Pyricularia grisea (Magnaporthe grisea). Based on a dendrogram constructed by RFLP analysis of rDNA, isolates that carry MAGGY elements were classified into a single cluster that comprised four rDNA types. However, in a few members of this cluster, exemplified by isolates from common millet (Panicum miliaceum), the MAGGY element has distinct features. Southern analysis suggested that these isolates possessed a single copy of a MAGGY-related sequence whose restriction map differed from that of MAGGY itself. Sequence analysis revealed that the MAGGY-related sequence was a degenerate form of MAGGY, characterized by numerous C:G to T:A transitions, which have often been reported to result from RIP (Repeat-induced point mutation) or RIP-like processes. However, the favored target site for C:G to T:A transitions in this fungus, determined by examining a total of 501 sites, was (A/T)pCp(A/T), which differs from that for the RIP process originally reported in Neurospora (CpA), and from that reported in Aspergillus (CpG). The fact that certain members of the cluster of MAGGY carriers retain a single copy of a degenerate MAGGY element implies that the ancestor of these isolates successfully "captured" the invading MAGGY element.

[Advances in interleukin-6 therapy]

Interleukin-6 (IL-6) exhibits multiple biologic activities such as regulation of immunological responses and hematopoiesis, promotion of acute inflammation, and stimulation of some malignant and non-malignant cell growth. The IL-6 receptor system consists of an IL-6 specific binding molecule, IL-6R and a signal transducer, gp130. Following gp130 dimerization, IL-6 activates multiple signaling pathways (Ras dependent MAPk cascade, STAT1-STAT3 heterodimer pathway, and STAT3 homodimer pathway). Several other cytokines including oncostatin M, IL-11, leukemia inhibitory factor (LIF), ciliary neurotrophic factor (CNTF) and cardiotropin-1 (CT-1) use gp130 as a common signal transducing molecule and therefore have similar biological activities. Two major in vivo functions of IL-6 are reported. Firstly, IL-6 acts as a growth factor of some malignant and non-malignant cells such as malignant plasma cells in multiple myeloma, mesangial cells in the kidney, and keratinocytes. Secondly, IL-6 mediates inflammatory and immune responses in rheumatoid arthritis, Castleman disease, psoriasis, cardiac myxoma, cachexia, and other inflammatory conditions. Recently, a humanized anti-IL-6 receptor antibody was developed. Neutralization of IL-6 activity by the humanized anti-IL-6 receptor antibody may be a new therapeutic approach for IL-6 related diseases such as multiple myeloma, Castleman disease and rheumatoid arthritis.

Anticytokine therapy in autoimmune diseases

Autoimmune reaction and inflammation observed in autoimmune diseases may be caused by the deregulated production of cytokines. Interleukin-6 (IL-6) is a pleiotropic cytokine with a wide range of biological activities such as support of hematopoiesis, regulation of acute phase reactions, and generation of immune responses. Uncontrolled hyperproduction of IL-6 causes plasmacytosis, hyper-gamma-globulinemia, thrombocytosis, mesangial cell proliferation of the kidney as well as inflammatory symptoms which are frequently observed in autoimmune diseases. Thus, interference with IL-6 signal transduction may be useful for autoimmune disease therapy. The pathogenic significance of IL-6 in autoimmune disorders and new therapeutic approaches involving blocking of IL-6 signal transduction are discussed.

Choledochoduodenal fistula at the anterior wall of the duodenal bulb: a rare complication of duodenal ulcer

A 38 year-old man was admitted to our hospital with the chief complaint of epigastralgia. His laboratory data revealed leukocytosis and increased serum amylase, and abdominal ultrasonography revealed diffuse swelling of the pancreas. Thus, he was diagnosed as having acute pancreatitis. Moreover, abdominal computed tomography showed pneumobilia in the gallbladder and the common bile duct. Gastroduodenal fiberscopy demonstrated peptic ulcer scars around a foramen with smooth margins at the anterior wall of the duodenal bulb. The bile juice flowed from the bottom of the foramen. Endoscopic retrograde cholangiopancreatography revealed the fistula between the common bile duct and the anterior wall of the duodenal bulb, but not the posterior wall. However, there was no pancreatico-biliary maljunction and no stones in the gallbladder or bile duct. This is a rare case of choledochoduodenal fistula at the anterior wall of the duodenal bulb caused by duodenal peptic ulcer disease.

Blockage of interleukin-6 receptor ameliorates joint disease in murine collagen-induced arthritis

OBJECTIVE

To clarify the role of interleukin-6 (IL-6) in the pathogenesis of collagen-induced arthritis (CIA).

METHODS

CIA was induced by immunizing twice at a 3-week interval with bovine type II collagen (CII) emulsified with complete adjuvant. Rat anti-mouse IL-6 receptor (anti-IL-6R) monoclonal antibody MR16-1 or isotype-matched control antibody KH-5 was then injected once intraperitoneally. Symptoms of arthritis were evaluated with a visual scoring system, and serum anti-CII antibody and IL-6 levels were measured by enzyme-linked immunosorbent assay. In addition, the CII responsiveness of splenic lymphocytes from mice with CIA was examined.

RESULTS

In mice with CIA, excess production of IL-6 in sera was observed within 24 hours after the first CII immunization, and then rapidly decreased. Serum IL-6 increased again beginning 14 days after immunization, in conjunction with the onset of arthritis. When MR16-1 was injected immediately after immunization with CII, it inhibited the development of arthritis in a dose-dependent manner. Furthermore, MR16-1-treated mice exhibited lower serum levels of IgG anti-CII antibody and reduced responsiveness of lymphocytes to CII. This suppressive effect was observed when MR16-1 was injected on day 0 or 3, but not when injected on day 7 or 14.

CONCLUSION

IL-6 produced after CII immunization appears to play an essential role in the immunity to CII, and anti-IL-6R antibody reduces the development of CIA by suppressing IL-6 signal transduction.

Treatment of rheumatoid synovitis with anti-reshaping human interleukin-6 receptor monoclonal antibody: use of rheumatoid arthritis tissue implants in the SCID mouse model

OBJECTIVE

To examine the effect of anti-reshaping human interleukin-6 receptor monoclonal antibody (anti-rsHuIL-6R mAb) on patients with rheumatoid arthritis (RA), using SCID mice in which human RA synovial tissue has been grafted (SCID-HuRAg).

METHODS

Tissue from human RA pannus was implanted subcutaneously in the backs of 69 SCID mice. Differences from human RA were examined pathologically. Anti-rsHuIL-6R mAb (100 microg) was administered intraperitoneally to mice once a week for 4 weeks. The implanted tissue was removed from the SCID-HuRAg mice on the fifth week after the initial treatment and examined pathologically. A group of SCID-HuRAg mice treated with control mAb, an auranofin-treated group, and an untreated group were used as controls. A total of 32 mice (8 in each group) were studied.

RESULTS

Histologic characteristics of the implanted tissues in SCID-HuRAg mice were very similar to those of human RA even 2 months after implantation. In addition, the presence of CD4-, CD8-, CD20-, IL-6-, tumor necrosis factor alpha-, tartrate-resistant acid phosphatase (TRAP)-, matrix metalloproteinase 1 (MMP-1)-, and MMP-9-positive cells was confirmed by immunohistochemical staining. A significant decrease in the number of inflammatory cells, MMP-positive cells, and TRAP-positive cells was observed in the anti-rsHuIL-6R mAb treatment group as compared with the control groups.

CONCLUSION

The SCID-HuRAg mouse is a useful model for evaluating the effectiveness of antirheumatic drugs. Anti-rsHuIL-6R mAb may have an antiinflammatory effect on RA synovitis and an inhibitory effect on osteoclasts.

[New molecular prognostic markers in gastric carcinoma]

Many molecular events have been reported as prognostic factors in gastric cancer. Amplifications of K-sam and c-met genes are often associated with poorly differentiated adenocarcinoma, while ERBB2 genes are amplified in well--differentiated adenocarcinomas of the stomach. Alterations of tumor suppressor regulators confer progression of gastric cancer. On the other hand, multi autocrine loops of growth factors/receptors in gastric cancer cells play a key role in the progression and metastasis of cancer cells. The overexpression of K-sam gene, occurs in 31.9% of gastric cancers, and the prognosis of patients with overexpression of K-sam gene is poorer than those without it. Multivariate analysis reveals that the overexpression of K-sam gene is an important factor for prognosis, lymphnode metastasis and the depth of tumor invasion of gastric carcinomas.

Intrathoracic multicentric Castleman disease: CT findings in 12 patients

PURPOSE

To assess the computed tomographic (CT) findings of intrathoracic involvement in multicentric Castleman disease.

MATERIALS AND METHODS

The study comprised 12 patients with lymph node biopsy-proved Castleman disease and multicentric involvement. The patients were aged 23-58 years (mean age, 42.9 years; five men, seven women). Seven patients underwent open lung biopsy (n = 3) or transbronchial lung biopsy (n = 4), which demonstrated lymphocytic interstitial pneumonitis.

RESULTS

All patients had systemic symptoms, polyclonal hypergammaglobulinemia, and bilateral hilar and mediastinal lymph node enlargement. The nodes showed mild to moderate enhancement after intravenous administration of contrast material. At thin-section CT, all 12 patients showed poorly defined centrilobular nodules. Thin-walled cysts were present in 10 patients, thickening of the bronchovascular bundles in 10, and interlobular septal thickening in nine. Less common findings were subpleural nodules, ground-glass attenuation, air-space consolidation, and bronchiectasis.

CONCLUSION

Multicentric Castleman disease is characterized by the presence of systemic symptoms, bilateral hilar and mediastinal lymphadenopathy, and centrilobular nodular opacities. The pulmonary parenchymal findings are due to the associated lymphocytic interstitial pneumonitis.