[A Case of Primary Squamous Cell Carcinoma of the Jejunum in the Ultra-Elderly]

We treated a 91-year-old man with squamous cell carcinoma that originated from his jejunum, which is very rare; only 8 cases have been reported previously.Surgery was performed because of the small bowel obstruction caused by the large cancerous mass, but he died 23 days later.Early detection and early treatment are important, especially for the ultra-elderly from a standpoint of tolerating surgery.

[A Case of Early Detection of Hepatocellular Carcinoma using Abdominal Ultrasonography after Endoscopic Submucosal Dissection for Early Gastric Cancer]

We treated an 82-year-old man with early gastric cancer using endoscopic submucosal resection.Ultrasonography, which was performed to screen for metastasis, revealed hepatocellular carcinoma, and the tumor was curatively resected.Ultrasonography can be considered a useful examination tool to detect double cancer, even in cases of early cancer.

Clinicopathological analysis for recurrence of stage Ib gastric cancer (according to the second English edition of the Japanese classification of gastric carcinoma)

BACKGROUND

The prognosis for patients with stage Ib (second English edition of the Japanese classification of gastric carcinoma) gastric cancer is promising, with an expected 5-year survival of 90%. Despite this relatively high survival rate, the outcome for patients who experience recurrence is poor. To date, however, prognostic and recurrence factors for stage Ib gastric cancer are poorly understood, and appropriate adjuvant chemotherapy protocols have not been developed.

METHODS

We retrospectively analyzed data from 86 stage Ib gastric cancer patients who underwent curative gastrectomy to determine the rates and predictive factors of recurrence.

RESULTS

Eleven patients showed recurrence, with a 12.8% 5-year cumulative recurrence rate. Nearly all of these patients were initially histologically diagnosed with poorly differentiated adenocarcinoma. Based on univariate analyses, recurrence was associated with gender and histological type. Multivariate analyses revealed that the only independent risk factor for recurrence was histologically undifferentiated-type adenocarcinoma. The 5-year survival rate of patients with undifferentiated-type adenocarcinoma was 84%. The predominant recurrence pattern was peritoneal dissemination, and was typically observed 1-3 years post-resection.

CONCLUSION

This retrospective study identified undifferentiated-type adenocarcinoma as the only risk factor for recurrence in stage Ib gastric cancer patients. Although randomized controlled studies are necessary, stage Ib gastric cancer patients with this identified recurrence risk factor would be candidates for adjuvant chemotherapy.

Role of EP4 prostaglandin E2 receptor in the ischemic liver

Prostaglandin E(2) (PGE(2)) mediates a variety of both innate and adaptive immunity responses through 4 distinct receptors, EP1-4. Recent studies have suggested the physiological and pathological role of EP4 in various inflammatory diseases. In this study, we investigated the importance of the EP4 receptor, and the efficacy of a selective EP4 agonist to alter hepatic ischemia/reperfusion (I/R) injury, an important cause of damage in liver resection and transplantation. We used an established murine I/R injury model, 70% partial hepatic ischemia for 90 minutes in male C57BL/6 mice. The local expression of EP4 messenger RNA (mRNA) in the naive and the ischemic liver at 2 hours after reperfusion was examined using RT-PCR analysis. Some mice received the EP4 selective agonist during I/R. Serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) were measured as markers of hepatic injury. EP4 expression in the liver was significantly up-regulated at 2 hours after reperfusion. Furthermore, treatment with EP4 agonist significantly inhibited hepatic injury at 6 hours after reperfusion. Our data suggest an inhibitory role of EP4 PGE(2) receptor in hepatic I/R injury and the therapeutic efficacy of a selective EP4 agonist for liver protection.

Function of the Vascular Endothelial Growth Factor Receptors Flt-1 and Flk-1/KDR in the Alloimmune Response In Vivo

BACKGROUND

We have recently reported that vascular endothelial growth factor (VEGF) functions as a proinflammatory cytokine to regulate the trafficking of leukocytes into allografts in the early posttransplant period. VEGF binds two major VEGF receptors: VEGFR-1 (flt-1) and VEGFR-2 (flk-1/KDR). Here, we wished to investigate the expression and function of VEGF receptors in the process of acute allograft rejection in vivo.

METHODS

We performed fully MHC-mismatched C57BL/6 (H-2b) into BALB/c (H-2d) vascularized heterotopic murine cardiac transplants and we examined the expression of VEGF and VEGF receptors by immunohistochemistry during acute allograft rejection. Next, we treated mice with specific neutralizing monoclonal antibodies against murine VEGFR-1 and VEGFR-2 and examined their effect on the development of acute allograft rejection by histology and by analysis of graft survival. The intragraft expression of cytokines and chemokines were also evaluated by quantitative real-time PCR analysis.

RESULTS

The expression of VEGF, VEGFR-1 and VEGFR-2 were significantly up-regulated during allograft rejection as compared to isografts. Administration of either anti-VEGFR-1 or anti-VEGFR-2 alone failed to inhibit allograft rejection. However, coadministration of both antibodies together inhibited leukocyte infiltration of allografts and prolonged allograft survival. Furthermore, the effect of VEGFR blockade was associated with the downregulation of intragraft cytokine and chemokine expression.

CONCLUSIONS

Our data suggest that VEGF-VEGFR interactions function in the alloimmune response in vivo. Targeting VEGFRs may represent a novel therapy to protect allografts following clinical transplantation.

Significance and therapeutic potential of prostaglandin E2 receptor in hepatic ischemia/reperfusion injury in mice

Prostaglandin E2 (PGE2) mediates a variety of innate and adaptive immunity through four distinct receptors: EP1-EP4. It has been suggested that each EP plays a unique and pivotal role in various disease conditions. We investigated the pathophysiological role of EP receptors in hepatic ischemia/reperfusion (I/R) injury. In this study, a 70% hepatic ischemic model was used in male C57BL/6 mice. Selective EP agonists were used to clarify the function of each PGE2 receptor in I/R injury. Although all four receptors were expressed in the naïve liver, EP4 expression was significantly upregulated after hepatic I/R. Although EP1, 2, or 3 agonists did not show any protective effect on liver function, the EP4 agonist significantly inhibited hepatic I/R injury as determined by serological and histological analyses. Furthermore, the EP4 agonist downregulated the local expressions of several proinflammatory cytokines, chemokines, and adhesion molecules in the early phase of reperfusion. In contrast, it augmented the local expression of an anti-inflammatory cytokine, interleukin 10. Additionally, the neutrophil accumulation was also inhibited by EP4 agonist treatment. Finally, to confirm the therapeutic efficacy of the EP4 agonist in hepatic I/R injury, the nonischemic shunt liver was removed after 120 minutes of ischemia, resulting in the death of 86% of control mice within 48 hours. In sharp contrast, 80% of mice treated with the EP4 agonist survived. In conclusion, the PGE2-EP4 signaling pathway has an inhibitory role in hepatic I/R injury. An EP4 agonist effectively protects against ischemic injury.

A novel small-molecule compound targeting CCR5 and CXCR3 prevents acute and chronic allograft rejection

BACKGROUND

Chemokines and chemokine receptors are critical in leukocyte recruitment, activation, and differentiation. Among them, CC chemokine receptor 5 (CCR5) and CXC chemokine receptor 3 (CXCR3) have been reported to play important roles in alloimmune responses and may be potential targets for posttransplant immunosuppression.

METHODS

Fully major histocompatibility complex (MHC)-mismatched murine cardiac and islet transplant models were used to test the effect in vivo of a novel, small-molecule compound TAK-779 by targeting CCR5 and CXCR3 in acute allograft rejection. An MHC class II mismatched cardiac transplant model was used to evaluate its efficacy in chronic allograft rejection. Intragraft expression of cytokines, chemokines, and chemokine receptors was measured by quantitative real-time polymerase chain reaction and by histological analysis.

RESULTS

Treatment of TAK-779 significantly prolonged allograft survival across the MHC barrier in two distinct transplant models. The treatment downregulated local immune activation as observed by the reduced expression of several chemokines, cytokines, and chemokine receptors. Thereby, the recruitment of CD4, CD8, and CD11c cells into transplanted allografts were inhibited. Furthermore, TAK-779 treatment significantly attenuated the development of chronic vasculopathy, fibrosis, and cellular infiltration.

CONCLUSIONS

Antagonism of CCR5 and CXCR3 has a substantial therapeutic effect on inhibiting both acute and chronic allograft rejection. CCR5 and CXCR3 are functional in the process of allograft rejection and may be potential targets in clinical transplantation in the future.

Clinical significance of programmed death-1 ligand-1 and programmed death-1 ligand-2 expression in human esophageal cancer

PURPOSE

The negative regulatory programmed death-1/programmed death-1 ligand (PD-1/PD-L) pathway in T-cell activation has been suggested to play an important role in tumor evasion from host immunity. In this study, we investigated the expression of PD-L1 and PD-L2 in human esophageal cancer to define their clinical significance in patients' prognosis after surgery.

EXPERIMENTAL DESIGN

PD-L1 and PD-L2 gene expression was evaluated in 41 esophagectomy patients by real-time quantitative PCR. The protein expression was also evaluated with newly generated monoclonal antibodies that recognize human PD-L1 (MIH1) and PD-L2 (MIH18).

RESULTS

The protein and the mRNA levels of determination by immunohistochemistry and real-time quantitative PCR were closely correlated. PD-L-positive patients had a significantly poorer prognosis than the negative patients. This was more pronounced in the advanced stage of tumor than in the early stage. Furthermore, multivariate analysis indicated that PD-L status was an independent prognostic factor. Although there was no significant correlation between PD-L1 expression and tumor-infiltrating T lymphocytes, PD-L2 expression was inversely correlated with tumor-infiltrating CD8(+) T cells.

CONCLUSIONS

These data suggest that PD-L1 and PD-L2 status may be a new predictor of prognosis for patients with esophageal cancer and provide the rationale for developing novel immunotherapy of targeting PD-1/PD-L pathway.

Dual role of vascular endothelial growth factor in hepatic ischemia-reperfusion injury

BACKGROUND

Vascular endothelial growth factor (VEGF), a major angiogenic factor, mediates a variety of disease conditions through promotion of angiogenesis. It also plays a critical role as a potent proinflammatory cytokine in a variety of physiologic and pathologic immune responses. In the present study, we evaluated the expression of VEGF in hepatic warm ischemia-reperfusion (I/R) injury and examined the effect of recombinant human (rh)VEGF administration in an established murine model.

METHOD

The expression of VEGF in the liver was assessed by quantitative real-time polymerase chain reaction and immunohistochemistry during I/R injury using 70% partial hepatic ischemia model. The effect of rhVEGF administration on I/R injury was evaluated by measuring liver function and histology. In addition, local inducible nitric oxide synthase (iNOS) and endothelial NO synthase expressions were examined to address the underlying mechanisms.

RESULTS

The local expression of VEGF was significantly up-regulated at 2 hours after reperfusion after 60 minutes of ischemia compared with that in the naive liver. VEGF was expressed predominantly in CD11b+ cells infiltrating into the ischemic liver. The administration of rhVEGF had a significant protective effect on ischemic injury in the liver. This effect was associated with the up-regulation of iNOS expression in the rhVEGF-treated liver.

CONCLUSION

We demonstrate a dual role of VEGF in hepatic warm I/R injury. Although endogenous VEGF is expressed and functional to initiate hepatic I/R injury, exogenous rhVEGF has a beneficial effect on the ischemic liver. These data may provide new insights into the role of VEGF as well as pathophysiology of hepatic I/R injury.

Role of the ICOS-B7h Costimulatory Pathway in the Pathophysiology of Chronic Allograft Rejection

BACKGROUND

Inducible costimulator (ICOS) is the third member of the CD28 superfamily and has a unique role in T cell activation and function. Recent studies indicated that the ICOS-B7h pathway plays an important role in alloimmune responses. We further investigated the role of the ICOS pathway in the pathologic process of chronic rejection in vivo.

METHODS

An established major histocompatibility complex class II disparate cardiac transplantation model was used. We treated mice with a blocking anti-B7h monoclonal antibody (mAb) either in the initiation phase (early blockade) or in the progression phase (delayed blockade) of disease. In addition, some mice received mAb in the entire period (whole blockade). At 6 weeks after transplantation, cardiac grafts were evaluated by histopathologic analysis in terms of vasculopathy, fibrosis, and cellular infiltration. The intragraft expressions of cytokines and chemokines were also examined by quantitative real-time polymerase chain reaction analysis.

RESULTS

Early blockade of the ICOS-B7h pathway did not show any protective effect on chronic allograft rejection compared with untreated controls. In contrast, delayed blockade significantly inhibited the development of vasculopathy, fibrosis, and cellular infiltration (P=0.043, P=0.004, and P=0.03 vs. untreated control, respectively). Interestingly, whole blockade did not prevent the chronic rejection process. Furthermore, the inhibitory effect of delayed ICOS blockade on chronic rejection was associated with down-regulation of local intragraft expression of several cytokines and chemokines.

CONCLUSIONS

These data suggest that the ICOS-B7h pathway is critical in the activation of effector/memory T cells that are necessary for the progression of chronic rejection and provide the rationale to develop novel and specific therapies to prevent this process.

Prognostic significance of localized p27Kip1 and potential role of Jab1/CSN5 in pancreatic cancer

p27Kip1 belongs to the family of small polypeptides collectively termed cyclin-dependent kinase inhibitors, which negatively regulate the cell cycle progression. In various human cancers, the reduced p27Kip1 expression correlates well with poor prognosis. Recently, Jab1/CSN5, the fifth component of the COP9 signalosome complex, was found to specifically translocate p27Kip1 from the nucleus to the cytoplasm, and reduce the protein level of p27Kip1 by accelerating its degradation. In this study, we investigated the expression of p27Kip1 and Jab1 in 61 cases with pancreatic ductal adenocarcinoma. The p27Kip1 expression was positive in 41% (25/61) of the tumors. Of the 25 positive tumors, 12 cases had p27Kip1 positive expression mainly in the nucleus of the tumor cells, while 13 cases had p27Kip1 in the cytoplasm as well as in the nucleus. Among a variety of clinicopathological factors, only tumor status was inversely correlated with p27Kip1 expression (p=0.019). The Jab1 expression was detected both in the nucleus and the cytoplasm in almost all pancreatic cancer cells. The intensity of Jab1 expression in tumor cells, especially in the cytoplasm, was much stronger than in normal pancreatic ductal epithelial cells. The patients with positive p27Kip1 expression had significantly better prognosis than ones with negative p27Kip1 expression (p=0.008). Furthermore, 12 patients with exclusively nuclear p27Kip1 expression, but not 13 patients with both nuclear and cytoplasmic p27Kip1 expression, had significantly better prognosis than 36 patients with negative p27Kip1 expression (p=0.009). In multivariate survival analysis, localized p27Kip1 expression was an independent prognostic factor (p=0.016). The results of our study suggested that the mislocalization as well as the downregulation of p27Kip1 had significant prognostic value in pancreatic cancer and that Jab1 might play an important role in carcinogenesis of pancreatic cancer. Cell cycle control targeting p27Kip1 might be a promising future therapeutic modality against pancreatic cancer.

Modification of the single unpaired sulfhydryl group of beta-lactoglobulin under high pressure and the role of intermolecular S-S exchange in the pressure denaturation [single SH of beta-lactoglobulin and pressure denaturation]

Chemical modification reactions of the unpaired sulfhydryl group of beta-lactoglobulin (LG) under high pressure and the role of this group in the pressure-induced denaturation were investigated. When LG was incubated at 400 MPa (pH 6.8) for 1 h, dimerization through intermolecular reaction of SH was observed. The generation of the covalently linked dimers were prevented by the presence of N-ethylmaleimide (NEM), an agent for SH-specific modification. The reactivity of the SH group of LG, which is buried inside in its native state, was increased by high pressure, as a result of its exposure to the protein surface accompanied by the pressure denaturation. The effect of NEM was also observed in the fluorescence change caused by high pressure, in both the intrinsic fluorescence of LG and the retinol fluorescence of the LG-retinol complex. The control showed an irreversible change at neutral pH, but it became mostly reversible in the presence of NEM. Compatible results were obtained by CD spectroscopy. Inter- and intramolecular reactions of the SH group are suggested to be main causes for the pressure-induced irreversible denaturation of LG.