Greb1 Transiently Accelerates Pancreatic β-Cell Proliferation in Diabetic Mice Exposed to Estradiol

Decrease of pancreatic β cells leads to diabetes. In an inducible cAMP early suppressor (ICER-Iγ) transgenic mouse model of severe type 2 diabetes with reduced insulin production and depleted β cells, supplementation with high concentrations of 17β-estradiol (E2) markedly enhances β-cell proliferation and normalizes glucose levels. The current study explored the underlying mechanisms leading to a dynamic increase of β cells and pathologic changes in diabetic mice exposed to E2. Gene expression profiling of pancreatic islets of 6-month-old ICER-transgenic mice recovering from diabetes due to elevated E2 levels identified growth regulation by estrogen in breast cancer 1 (Greb1) as a gene significantly up-regulated during the recovery phase. To substantiate this, β-cell-specific Greb1-deficient mice were generated, and Greb1 was shown to be essential for recovery of depleted β cells in diabetic mice. Graft growth and glucose lowering were observed in 50 islets with increased Greb1 expression transplanted adjacent to E2 pellets beneath the kidney capsule of streptozotocin-induced diabetic mice. Greb1 expression due to a drastic increase in exogenous or endogenous E2 was transient and closely correlated with changes in E2-related and some cell cycle-related genes. These findings provide new insights into in vivo proliferation of deficient β cells and suggest the possibility of new therapeutic approaches targeting pancreatic β cells that could revolutionize the concept of diabetes treatment, which has been considered difficult to cure completely.

Acceptance of Murine Islet Allografts Without Immunosuppression in Inguinal Subcutaneous White Adipose Tissue Pretreated With bFGF

Prevention of immune rejection without immunosuppression is the ultimate goal of transplant immunobiology. One way to achieve this in cellular transplantation, such as with islet transplantation, is to create a favorable local environment at the transplant site. In the current study, we found that C57BL/6 mice with streptozotocin-induced diabetes remained normoglycemic for >1 year after transplantation of BALB/c islets without immunosuppression when the inguinal subcutaneous white adipose tissue (ISWAT) was the site of transplantation and when the site was pretreated with basic fibroblast growth factor. Mechanistically, mesenchymal stem cells (MSCs) expanded in the ISWAT after the treatment was found to produce transforming growth factor-β (TGF-β), and prevention of islet allograft rejection could be achieved by cotransplantation with syngeneic MSCs isolated from the ISWAT after the treatment, which was abolished by anti-TGF-β antibody treatment. Importantly, TGF-β-producing cells remained present at the site of cotransplantation up to the end of observation period at 240 days after transplantation. These findings indicate that prevention of islet allograft rejection without immunosuppression is feasible with the use of syngeneic TGF-β-producing MSCs expanded in the ISWAT after the treatment with bFGF, providing a novel strategy for prevention of islet allograft rejection without immunosuppression.

Amelioration of Murine Diabetic Nephropathy with a SGLT2 Inhibitor Is Associated with Suppressing Abnormal Expression of Hypoxia-Inducible Factors

Diabetic nephropathy (DN), once manifested, is unlikely to completely recover. Factors that influence DN progression were explored by investigating the process of glomerulosclerosis and interstitial fibrosis and chronological changes in glucose, albuminuria, hyperfiltration, and expressions of sodium-glucose cotransporter 2 (SGLT2) and hypoxia-inducible factors (HIFs) up to 50 weeks in inducible cAMP early repressor transgenic mice, a model of severe DN. Long-term intervention with the SGLT2 inhibitor canagliflozin or islet transplantation or heminephrectomy was used. Inducible cAMP early repressor transgenic mice exhibited progressive diabetic glomerulosclerosis and mild interstitial fibrosis, and expressed extensive HIF-1α and HIF-2α in glomerulus and tubules, with sustained hyperfiltration up to 50 weeks. Canagliflozin ameliorated glomerulosclerosis/interstitial fibrosis gradually and reduced HIF overexpression. Islet-transplanted mice exhibited no amelioration. None of the heminephrectomized diabetic mice survived the hyperfiltration overload, but all of the canagliflozin-treated mice survived with re-expressions of HIF-1α and HIF-2α. These results suggest that persistent glomerular hyperfiltration might initiate glomerular injury, and persistent overexpression of HIFs could promote the development of glomerulosclerosis and interstitial fibrosis. Canagliflozin attenuated both changes. Oxidative stress or hypoxia was undetectable in this model. The abnormal expression of HIF-1α and HIF-2α may be a potential therapeutic target for preventing glomerulosclerosis and interstitial fibrosis.

Improvement of hepatocyte engraftment by co-transplantation with pancreatic islets in hepatocyte transplantation

Because of the fragility of isolated hepatocytes, extremely poor engraftment of transplanted hepatocytes remains a severe issue in hepatocyte transplantation. Therefore, improving hepatocyte engraftment is necessary to establish hepatocyte transplantation as a standard therapy. Since the pancreatic islets are known to have favorable autocrine effects, we hypothesized that the transplanted islets might influence not only the islets but also the nearby hepatocytes, subsequently promoting engraftment. We evaluated the effects of islet co-transplantation using an analbuminemic rat model (in vivo model). Furthermore, we established a mimicking in vitro model to investigate the underlying mechanisms. In an in vivo model, the hepatocyte engraftment was significantly improved only when the islets were co-transplanted to the nearby hepatocytes (p < 0.001). Moreover, the transplanted hepatocytes appeared to penetrate the renal parenchyma together with the co-transplanted islets. In an in vitro model, the viability of cultured hepatocytes was also improved by coculture with pancreatic islets. Of particular interest, the coculture supernatant alone could also exert beneficial effects comparable to islet coculture. Although insulin, VEGF, and GLP-1 were selected as candidate crucial factors using the Bio-Plex system, beneficial effects were partially counteracted by anti-insulin receptor antibodies. In conclusion, this study demonstrated that islet co-transplantation improves hepatocyte engraftment, most likely due to continuously secreted crucial factors, such as insulin, in combination with providing favorable circumstances for hepatocyte engraftment. Further refinements of this approach, especially regarding substitutes for islets, could be a promising strategy for improving the outcomes of hepatocyte transplantation.

Identification of IGFBP2 and IGFBP3 As Compensatory Biomarkers for CA19-9 in Early-Stage Pancreatic Cancer Using a Combination of Antibody-Based and LC-MS/MS-Based Proteomics

Pancreatic cancer is one of the most lethal tumors, and reliable detection of early-stage pancreatic cancer and risk diseases for pancreatic cancer is essential to improve the prognosis. As 260 genes were previously reported to be upregulated in invasive ductal adenocarcinoma of pancreas (IDACP) cells, quantification of the corresponding proteins in plasma might be useful for IDACP diagnosis. Therefore, the purpose of the present study was to identify plasma biomarkers for early detection of IDACP by using two proteomics strategies: antibody-based proteomics and liquid chromatography-tandem mass spectrometry (LC-MS/MS)-based proteomics. Among the 260 genes, we focused on 130 encoded proteins with known function for which antibodies were available. Twenty-three proteins showed values of the area under the curve (AUC) of more than 0.8 in receiver operating characteristic (ROC) analysis of reverse-phase protein array (RPPA) data of IDACP patients compared with healthy controls, and these proteins were selected as biomarker candidates. We then used our high-throughput selected reaction monitoring or multiple reaction monitoring (SRM/MRM) methodology, together with an automated sample preparation system, micro LC and auto analysis system, to quantify these candidate proteins in plasma from healthy controls and IDACP patients on a large scale. The results revealed that insulin-like growth factor-binding protein (IGFBP)2 and IGFBP3 have the ability to discriminate IDACP patients at an early stage from healthy controls, and IGFBP2 appeared to be increased in risk diseases of pancreatic malignancy, such as intraductal papillary mucinous neoplasms (IPMNs). Furthermore, diagnosis of IDACP using the combination of carbohydrate antigen 19-9 (CA19-9), IGFBP2 and IGFBP3 is significantly more effective than CA19-9 alone. This suggests that IGFBP2 and IGFBP3 may serve as compensatory biomarkers for CA19-9. Early diagnosis with this marker combination may improve the prognosis of IDACP patients.

Adjusting the 17β-Estradiol-to-Androgen Ratio Ameliorates Diabetic Nephropathy

Diabetes is manifested predominantly in males in experimental models, and compelling evidence suggests that 17β-estradiol (E2) supplementation improves hyperglycemia in humans. We previously generated a severely diabetic transgenic (Tg) mouse model by β-cell–specific overexpression of inducible cAMP early repressor (ICER) and found that male but not female ICER-Tg mice exhibit sustained hyperglycemia and develop major clinical and pathologic features of human diabetic nephropathy (DN). Thus, we hypothesized that differences in circulating hormone levels have a key role in determining susceptibility to diabetes. Here, we examined whether DN in male ICER-Tg mice is rescued by adjusting the androgen-to-E2 ratio to approximate that in normoglycemic female ICER-Tg mice. We treated hyperglycemic male ICER-Tg mice with orchiectomy (ORX), E2 pellet implantation, or both. E2 pellet implantation at an early stage of DN with or without ORX caused a rapid drop in blood glucose and a dramatic increase in β-cell number, and it markedly inhibited DN progression [namely, E2 reduced glomerulosclerosis, collagen 4 deposition and albuminuria, and prevented hyperfiltration]. Furthermore, E2 pellet implantation was more effective than ORX alone and induced a remarkable improvement, even when initiated at advanced-stage DN. In contrast, induction of normoglycemia by islet transplant in ICER-Tg mice eliminated albuminuria but was less effective than E2 + ORX in reducing glomerulosclerosis, collagen 4 deposition, and hyperfiltration. These findings indicate that E2 treatment is effective, even after establishment of DN, whereas glucose normalization alone does not improve sclerotic lesions. We propose that E2 intervention is a potential therapeutic option for DN.

Associations between vitamin D receptor (VDR) gene polymorphisms and colorectal cancer risk and effect modifications of dietary calcium and vitamin D in a Japanese population

Much interest has been drawn to possible associations between vitamin D receptor (VDR) gene polymorphisms and colorectal cancer risk in conjunction with potentially protective effects of calcium and vitamin D. In a study of 685 cases of colorectal cancer and 778 community controls in Japan, we examined the associations of the FokI, BsmI, ApaI, and TaqI polymorphisms with colorectal cancer risk and effect modification by dietary calcium and vitamin D. Genotypes were determined by the PCR-RFLP method. The ApaI polymorphism seemed to be associated with a decreased risk of colorectal cancer, particularly of rectal cancer. The adjusted odds ratio of colorectal cancer for the ApaI AA and Aa genotypes combined versus the aa genotype was 0.83 (95% confidence interval [CI] 0.67-1.02), and the corresponding value for rectal cancer was 0.75 (95%CI 0.56-0.99). A decreased risk of colorectal cancer for the ApaI AA and Aa genotypes combined was more evident in individuals with high calcium intake (interaction p=0.055). The FokI polymorphism seemed to be associated with a decreased risk of colon cancer among those with high vitamin D intake (interaction p=0.09). The BsmI and TaqI polymorphisms were unrelated to colorectal cancer risk, and the null associations were not modified by calcium or vitamin D intake. In conclusion, the ApaI polymorphism may be associated with a decreased risk of colorectal cancer in Japanese, dependent on dietary calcium intake.

Folate-related nutrients, genetic polymorphisms, and colorectal cancer risk: the fukuoka colorectal cancer study

One-carbon metabolism plays an important role in colorectal carcinogenesis. Meta-analyses have suggested protective associations of folate and vitamin B6 intakes with colorectal cancer primarily based on studies in Caucasians, and genetic polymorphisms pertaining to the folate metabolism have been a matter of interest. Less investigated are the roles of methionine synthase (MTR) and thymidylate synthetase (TS) polymorphisms in colorectal carcinogenesis. In a study of 816 cases and 815 community controls in Japan, we investigated associations of dietary intakes of folate, methionine, vitamin B2, vitamin B6, and vitamin B12 with colorectal cancer risk. The associations with MTR 2756A>G, MTRR 66A>G, and TSER repeat polymorphism were examined in 685 cases and 778 controls. Methionine and vitamin B12 intakes were inversely associated with colorectal cancer risk, but the associations were totally confounded by dietary calcium and n-3 fatty acids. The other nutrients showed no association with the risk even without adjustment for calcium and n-3 fatty acids. The TSER 2R allele was dose-dependently associated with an increased risk. The MTR and MTRR polymorphisms were unrelated to colorectal cancer risk. There was no measurable gene-gene or gene-nutrient interaction, but increased risk associated with the TSER 2R allele seemed to be confined to individuals with high folate status. This study does not support protective associations for folate and vitamin B6. The TSER 2R allele may confer an increased risk of colorectal cancer. The role of the TSER polymorphism in colorectal carcinogenesis may differ by ethnicity.

Sugars, sucrose and colorectal cancer risk: the Fukuoka colorectal cancer study

OBJECTIVE

A diet high in sugars may promote colorectal carcinogenesis, but it remains uncertain whether high intake of sugars or sucrose confers increased risk of colorectal cancer. The authors investigated the associations of sugars and sucrose intake with colorectal cancer risk in a community-based case-control study in Japan.

METHODS

The study subjects comprised 816 incident cases of colorectal cancer and 815 community controls. Consumption frequencies and portion sizes of 148 food and beverage items were ascertained by a computer-assisted interview. The authors used the consumption of 29 food items to estimate sugars and sucrose intake. The odds ratios of colorectal cancer risk according to intake categories were obtained using a logistic regression model with adjustment for potential confounding variables.

RESULTS

Overall, intakes of sugars and sucrose were not related to colorectal cancer risk either in men or women. The association between sugars intake and colorectal cancer risk differed by smoking status and alcohol use in men, but not in women. In men, sugars intake tended to be associated with colorectal cancer risk inversely among never-smokers and positively among male ever-smokers (interaction p=0.01). Sugars intake was associated with an increased risk among men with no alcohol consumption, but was unrelated to the risk among male alcohol drinkers (interaction p=0.02). Body mass index did not modify the association with sugars intake in either men or women.

CONCLUSION

Sugars intake was associated with increased risk of colorectal cancer among smokers and non-alcohol drinkers in men selectively.

Pretreatment of donor islets with the Na(+) /Ca(2+) exchanger inhibitor improves the efficiency of islet transplantation

Pancreatic islet transplantation is an attractive therapy for the treatment of insulin-dependent diabetes mellitus. However, the low efficiency of this procedure necessitating sequential transplantations of islets with the use of 2-3 donors for a single recipient, mainly due to the early loss of transplanted islets, hampers its clinical application. Previously, we have shown in mice that a large amount of HMGB1 is released from islets soon after their transplantation and that this triggers innate immune rejection with activation of DC, NKT cells and neutrophils to produce IFN-γ, ultimately leading to the early loss of transplanted islets. Thus, HMGB1 release plays an initial pivotal role in this process; however, its mechanism remains unclear. Here we demonstrate that release of HMGB1 from transplanted islets is due to hypoxic damage resulting from Ca(2+) influx into β cells through the Na(+) /Ca(2+) exchanger (NCX). Moreover, the hypoxia-induced β cell damage was prevented by pretreatment with an NCX-specific inhibitor prior to transplantation, resulting in protection and long-term survival of transplanted mouse and human islets when grafted into mice. These findings suggest a novel strategy with potentially great impact to improve the efficiency of islet transplantation in clinical settings by targeting donor islets rather than recipients.

Dietary polyphenols and colorectal cancer risk: The Fukuoka colorectal cancer study

AIM: To investigate the associations between dietary intake of polyphenols and colorectal cancer.

METHODS: The study subjects were derived from the Fukuoka colorectal cancer study, a community-based case-control study. The study subjects were 816 cases of colorectal cancer and 815 community-based controls. The consumption of 148 food items was assessed by a computer-assisted interview. We used the consumption of 97 food items to estimate dietary intakes of total, tea and coffee polyphenols. The Phenol-Explorer database was used for 92 food items. Of the 5 foods which were not listed in the Phenol-Explorer Database, polyphenol contents of 3 foods (sweet potatoes, satoimo and daikon) were based on a Japanese study and 2 foods (soybeans and fried potatoes) were estimated by ORAC-based polyphenol contents in the United States Department of Agriculture Database. Odds ratios (OR) and 95%CI of colorectal cancer risk according to quintile categories of intake were obtained by using logistic regression models with adjustment for age, sex, residential area, parental history of colorectal cancer, smoking, alcohol consumption, body mass index 10 years before, type of job, leisure-time physical activity and dietary intakes of calcium and n-3 polyunsaturated fatty acids.

RESULTS: There was no measurable difference in total or tea polyphenol intake between cases and controls, but intake of coffee polyphenols was lower in cases than in controls. The multivariate-adjusted OR of colorectal cancer according to quintile categories of coffee polyphenols (from the first to top quintile) were 1.00 (referent), 0.81 (95%CI: 0.60-1.10), 0.65 (95%CI: 0.47-0.89), 0.65 (95%CI: 0.46-0.89) and 0.82 (95%CI: 0.60-1.10), respectively (P_trend = 0.07). Similar, but less pronounced, decreases in the OR were also noted for the third and fourth quintiles of total polyphenol intake. Tea polyphenols and non-coffee polyphenols showed no association with colorectal cancer risk. The site-specific analysis, based on 463 colon cancer cases and 340 rectal cancer cases, showed an inverse association between coffee polyphenols and colon cancer. The multivariate-adjusted OR of colon cancer for the first to top quintiles of coffee polyphenols were 1.00 (referent), 0.92 (95%CI: 0.64-1.31), 0.75 (95%CI: 0.52-1.08), 0.69 (95%CI: 0.47-1.01), and 0.68 (95%CI: 0.46-1.00), respectively (P_trend = 0.02). Distal colon cancer showed a more evident inverse association with coffee polyphenols than proximal colon cancer. The association between coffee polyphenols and rectal cancer risk was U-shaped, with significant decreases in the OR at the second to fourth quintile categories. There was also a tendency that the OR of colon and rectal cancer decreased in the intermediate categories of total polyphenols. The decrease in the OR in the intermediate categories of total polyphenols was most pronounced for distal colon cancer. Intake of tea polyphenols was not associated with either colon or rectal cancer. The associations of coffee consumption with colorectal, colon and rectal cancers were almost the same as observed for coffee polyphenols. The trend of the association between coffee consumption and colorectal cancer was statistically significant.

CONCLUSION: The present findings suggest a decreased risk of colorectal cancer associated with coffee consumption.

Altered plasma apolipoprotein modifications in patients with pancreatic cancer: protein characterization and multi-institutional validation

Background

Among the more common human malignancies, invasive ductal carcinoma of the pancreas has the worst prognosis. The poor outcome seems to be attributable to difficulty in early detection.

Methods

We compared the plasma protein profiles of 112 pancreatic cancer patients with those of 103 sex- and age-matched healthy controls (Cohort 1) using a newly developed matrix-assisted laser desorption/ionization (oMALDI) QqTOF (quadrupole time-of-flight) mass spectrometry (MS) system.

Results

We found that hemi-truncated apolipoprotein AII dimer (ApoAII-2; 17252 m/z), unglycosylated apolipoprotein CIII (ApoCIII-0; 8766 m/z), and their summed value were significantly decreased in the pancreatic cancer patients [P = 1.36×10⁻²¹, P = 4.35×10⁻¹⁴, and P = 1.83×10⁻²⁴ (Mann-Whitney U-test); area-under-curve values of 0.877, 0.798, and 0.903, respectively]. The significance was further validated in a total of 1099 plasma/serum samples, consisting of 2 retrospective cohorts [Cohort 2 (n = 103) and Cohort 3 (n = 163)] and a prospective cohort [Cohort 4 (n = 833)] collected from 8 medical institutions in Japan and Germany.

Conclusions

We have constructed a robust quantitative MS profiling system and used it to validate alterations of modified apolipoproteins in multiple cohorts of patients with pancreatic cancer.

Estrogen receptor-β gene polymorphism and colorectal cancer risk: effect modified by body mass index and isoflavone intake

Estrogen receptor (ER)-β signaling has generally been implicated in protection against colorectal cancer. The ER-β gene cytosine-adenine (ESR2 CA) repeat polymorphism was reported to be associated with colorectal cancer, although showing contradicting results probably caused by ethnicity or age distribution of the subjects. We investigated the association between this polymorphism and the colorectal cancer risk in a community-based case-control study in Japan (685 cases/778 controls), including only subjects younger than 75. The effect modifications of the body mass index (BMI) and isoflavone intake were also examined. ESR2 CA repeat polymorphism was determined by polymerase chain reaction using fluorescein-labeled primers. CA repeat alleles were classified into short (S) allele (<22 repeats) and long (L) allele (≥ 22 repeats). Subjects were divided into three genotype groups (SS/SL/LL). The risk of colon cancer, but not of rectal cancer, was increased with an increasing number of L alleles among postmenopausal women; age-adjusted odds ratio (OR) for SL and LL genotypes compared with the SS genotype were 1.78 and 2.91, respectively (trend p = 0.002). Increased risks of colon cancer associated with the L allele were more evident among postmenopausal women with low BMI (<25 kg m(-2)) or with high isoflavone intake. Such associations were not observed among men or premenopausal women. Having longer ESR2 CA repeat increases colon cancer risk among postmenopausal women younger than 75, possibly with modification of BMI and isoflavone intake. Aging and estrogenic condition may be important in the colon cancer pathogenesis associated with ESR2 CA repeat polymorphism.

Dietary intakes of retinol, carotenes, vitamin C, and vitamin E and colorectal cancer risk: the Fukuoka colorectal cancer study

It has long been a matter of interest whether antioxidant vitamins are protective against colorectal cancer as well as human cancers in general, but epidemiological evidence is inconclusive. We investigated associations of dietary intakes of retinol and antioxidant vitamins with colorectal cancer risk in 816 incident cases of histologically confirmed colorectal cancer and 815 controls randomly selected for the Fukuoka colorectal cancer study in Japan. Dietary intakes were assessed by a PC-assisted interview regarding 148 food items. Statistical adjustment was made for body mass index, physical activity, calcium, and n-3 fatty acid intake and other factors. Retinol intake was significantly, inversely associated with colorectal cancer risk; the odds ratio for the highest vs. lowest was 0.55 (95% CI: 0.35, 0.88; P (trend) = 0.01) in women, but a modest increase in the risk was observed among men with the highest intake of retinol. Liver was the major source of retinol intake and showed similar associations with colorectal cancer risk in men and women. Intake of carotenes, vitamin C, and vitamin E were not related to colorectal cancer risk in either men or women. The study did not support a hypothesis that dietary intake of antioxidant vitamins is protective in the development of colorectal cancer.

Microsomal epoxide hydrolase polymorphisms, cigarette smoking, and risk of colorectal cancer: the Fukuoka Colorectal Cancer Study

Microsomal epoxide hydrolase (EPHX1) plays an important role in the activation and detoxification of polycyclic aromatic hydrocarbons, carcinogens found in cigarette smoke. Polymorphisms in exon 3 (Y113H) and exon 4 (H139R) of the EPHX1 have been associated with enzyme activity. We investigated the risk of colorectal cancer in relation to the EPHX1 Y113H and H139R polymorphisms and assessed effect modifications of cigarette smoking and the other covariates. The interaction between the EPHX1 polymorphisms and selected genetic polymorphisms was also examined. We used data from Fukuoka Colorectal Cancer Study, a community-based case-control study, including 685 cases and 778 controls. In-person interviews were conducted to assess lifestyle factors. The EPHX1 Y113H and H139R polymorphisms were determined by the TaqMan assay and the polymerase chain reaction-restriction fragment length polymorphism, respectively. Neither of the two polymorphisms nor the imputed EPHX1 phenotype was associated with colorectal cancer risk. Cigarette smoking and alcohol intake showed no effect modification on the association with the EPHX1 polymorphisms or the imputed EPHX1 phenotype. Increased risks of colorectal cancer associated with the 113Y allele and imputed EPHX1 phenotype were observed among individuals with high body mass index (BMI; ≥25.0 kg/m(2)), but not among those with low BMI (<25.0 kg/m(2)). The risk decreased with an increasing number of the 139R allele in the null genotypes of GSTM1/GSTT1. It is unlikely that the EPHX1 polymorphisms play an important role in colorectal carcinogenesis. The observed interactions of the EPHX1 polymorphisms with BMI and the GSTM1/GSTT1 genotypes warrant further investigation.

Genetic polymorphisms of XRCC1, alcohol consumption, and the risk of colorectal cancer in Japan

Background

X-ray cross-complementing group 1 (XRCC1) polymorphisms affect DNA repair capacity and may therefore be of importance in colorectal carcinogenesis. Alcohol consumption, an important risk factor for colorectal cancer, may induce carcinogenesis through DNA damage caused by the toxic effects of alcohol or its metabolites. Therefore, we examined the associations of XRCC1 Arg399Gln, Arg280His, and Arg194Trp polymorphisms with colorectal cancer and the impact of the association between alcohol consumption and colorectal cancer risk.

Methods

This case-control study in Fukuoka, Japan including 685 cases and 778 controls. The cases were incident patients with histologically confirmed colorectal adenocarcinoma. The controls were randomly selected community subjects.

Results

The XRCC1 399Gln/Gln genotype was significantly associated with colorectal cancer risk (adjusted odds ratio [OR] 1.57, 95% CI 1.01–2.42; relative to 399Arg/Arg genotype). The association was strongest in individuals with high alcohol consumption. The Arg280His polymorphism modified the association between alcohol consumption and colorectal cancer risk (interaction P = 0.049). The OR of colorectal cancer in individuals with the 280His allele was 0.45 (95% CI 0.26–0.78) as compared with the 280Arg/Arg genotype limited to the 399Gln allele (interaction P = 0.001). The adjusted ORs for 399Gln/Gln-280Arg/Arg-194Arg/Arg and 399Arg/Gln-280Arg/Arg-194Arg/Trp were 1.71 (95% CI 1.02–2.87) and 1.57 (95% CI 1.05–2.33), respectively, with 399Arg/Arg-280Arg/Arg-194Arg/Arg as reference (interaction P = 0.418).

Conclusions

The findings are additional evidence that individuals with the XRCC1 399Gln/Gln genotype have an increased risk of colorectal cancer, and that XRCC1 polymorphisms have an important role in colorectal cancer risk associated with alcohol consumption or gene-gene interaction.

Identification of adipophilin as a potential plasma biomarker for colorectal cancer using label-free quantitative mass spectrometry and protein microarray

BACKGROUND

The aim of this study was to identify a new plasma biomarker for use in early detection of colorectal cancer.

METHODS

Using the combination of hollow fiber membrane (HFM)-based low-molecular weight protein enrichment and two-dimensional image converted analysis of liquid chromatography and mass spectrometry (2DICAL), we compared the plasma proteome of 22 colorectal cancer patients with those of 21 healthy controls. An identified biomarker candidate was then validated in two larger cohorts [validation-1 (n = 210) and validation-2 (n = 113)] using a high-density reverse-phase protein microarray.

RESULTS

From a total of 53,009 mass peaks, we identified 103 with an area under curve (AUC) value of 0.80 or higher that could distinguish cancer patients from healthy controls. A peak that increased in colorectal cancer patients, with an AUC of 0.81 and P value of 0.0004 (Mann-Whitney U test), was identified as a product of the PLIN2 gene [also known as perilipin-2, adipose differentiation-related protein (ADRP), or adipophilin]. An increase in plasma adipophilin was consistently observed in colorectal cancer patients, including those with stage I or stage II disease (P < 0.0001, Welch's t test). Immunohistochemical analysis revealed that adipophilin is expressed primarily in the basal sides of colorectal cancer cells forming polarized tubular structures, and that it is absent from adjacent normal intestinal mucosae.

CONCLUSIONS

Adipophilin is a plasma biomarker potentially useful for the detection of early-stage colorectal cancer.

IMPACT

The combination of HFM and 2DICAL enables the comprehensive analysis of plasma proteins and is ideal for use in all biomarker discovery studies.

Actions of the Japanese Pancreas and Islet Transplantation Association regarding transplanted human islets isolated using Liberase HI

PURPOSE

The potential for introducing transmissible spongiform encephalopathy (TSE) into islet cells was indicated by recognizing that Liberase HI is isolated from Clostridium histolyticum grown in media containing brain-heart infusion broth. A national team within the Japanese Pancreas and Islet Transplantation Association implemented an islet transplantation program in Japan using Liberase HI. The program comprised 65 islet isolations from non-heart-beating donors and 34 transplants into 18 patients. Herein, we have summarized how the Association followed these recipients over the long term.

PROCEDURES

We established an ad hoc committee to follow recipients transplanted with islets isolated using Liberase HI after becoming informed of the associated dangers of using this enzyme. We also stopped islet transplantations using Liberase. The committee addressed the major concerns of the risk of the collagenase being contaminated with TSE and of the recipient follow-up. All recipients were examined by diffusion MRI and EEG and then scheduled for evaluation and follow-up by specialists in Creutzfeldt-Jakob disease (CJD). Bioassays of bovine spongiform encephalopathy prions in the enzyme proceeded using knock-in mice expressing bovine prion protein. These assays could detect contaminating prions at a dilution of 1 × 10(4). After inactivating its collagenase activity, Liberase HI was injected into the abdominal cavities of knock-in mice. Four months later, prion infectivity in Liberase HI was evaluated by immunohistochemical staining and Western blotting of spleen homogenates using anti-prion protein antibodies.

MAIN FINDINGS

Western blotting and immunohistochemical staining did not detect prions in Liberase HI. Diffusion MRI and EEG evaluations performed by CJD specialists confirmed that none of the transplanted recipients had CJD.

CONCLUSIONS

Three years of follow-up revealed that none of the Japanese recipients of islet transplants developed CJD. Prion bioassays showed that the Liberase HI used to isolate islets for transplantation was free of infectious TSE prions.

Soy food and isoflavone intake and colorectal cancer risk: the Fukuoka Colorectal Cancer Study

OBJECTIVE

It has been suggested that soy food and isoflavone intake may be protective against the risk of colorectal cancer. However, epidemiologic evidence remains sparse and inconsistent. We addressed this issue in the Fukuoka Colorectal Cancer Study.

MATERIAL AND METHODS

The study subjects were the 816 incident cases of histologically confirmed colorectal cancer and 815 community controls. Intakes of soy foods and isoflavones were assessed by in-person interview using a computer-assisted dietary method. Logistic regression analysis was applied to estimate odds ratio (OR) and 95% confidence interval (CI) of colorectal cancer with adjustment for dietary intakes of calcium and n-3 polyunsaturated fatty acids as well as for body mass index, physical activity, alcohol use, and other lifestyle factors.

RESULTS

Energy-adjusted intakes of soy foods (dry weight) and isoflavones were inversely associated with colorectal cancer risk in men and postmenopausal women, but not in premenopausal women. The multivariate-adjusted OR for the highest versus lowest quintile was 0.65 (95% CI 0.41-1.03, p for trend = 0.03) for soy foods and 0.68 (95% CI 0.42-1.10, p for trend = 0.051) for isoflavones in men. The corresponding values for postmenopausal women were 0.60 (95% CI 0.29-1.25, p for trend = 0.053) and 0.68 (95% CI 0.33-1.40, p for trend = 0.049). The site-specific analysis showed inverse associations of soy foods (p for trend = 0.007) and isoflavones (p for trend = 0.02) with rectal cancer in men.

CONCLUSION

The findings add to epidemiologic evidence for protective effects of soy foods and isoflavones in colorectal carcinogenesis.

Constipation and colorectal cancer risk: the Fukuoka Colorectal Cancer Study

Constipation has been suspected to be linked to colorectal cancer risk, but epidemiological evidence is inconclusive. We described the prevalence of constipation and related lifestyle factors in a community and examined the relation of constipation and other bowel habits to colorectal cancer risk. The prevalence study was based on 833 community controls in the Fukuoka Colorectal Cancer Study, and 212 cases of Dukes' stage A were used in a study on bowel habits and colorectal cancer risk. Bowel habits were assessed by in-person interview. Odds ratio (OR) and 95% confidence interval (CI) of colorectal cancer were estimated with adjustment for dietary and nondietary factors. Constipation was reported by 10.3% of men and 27.7% of women. Individuals with less frequent bowel movements had a lower intake of total energy and were physically less active. The multivariate-adjusted OR (95% CI) of colorectal cancer were 1.51 (1.02-2.25) for self-reported constipation, 1.60 (1.05-2.44) for functional constipation, and 1.24 (0.81-1.90) for infrequent bowel movements (<1 stool/day). Self-reported constipation was fairly common in Japanese adults. Constipation was associated with a moderately increased risk of colorectal cancer.

Reduced plasma level of CXC chemokine ligand 7 in patients with pancreatic cancer

BACKGROUND

Early detection is essential to improve the outcome of patients with pancreatic cancer. A noninvasive and cost-effective diagnostic test using plasma/serum biomarkers would facilitate the detection of pancreatic cancer at the early stage.

METHODS

Using a novel combination of hollow fiber membrane-based low-molecular-weight protein enrichment and LC-MS-based quantitative shotgun proteomics, we compared the plasma proteome between 24 patients with pancreatic cancer and 21 healthy controls (training cohort). An identified biomarker candidate was then subjected to a large blinded independent validation (n = 237, validation cohort) using a high-density reverse-phase protein microarray.

RESULTS

Among a total of 53,009 MS peaks, we identified a peptide derived from CXC chemokine ligand 7 (CXCL7) that was significantly reduced in pancreatic cancer patients, showing an area under curve (AUC) value of 0.84 and a P value of 0.00005 (Mann-Whitney U test). Reduction of the CXCL7 protein was consistently observed in pancreatic cancer patients including those with stage I and II disease in the validation cohort (P < 0.0001). The plasma level of CXCL7 was independent from that of CA19-9 (Pearson's r = 0.289), and combination with CXCL7 significantly improved the AUC value of CA19-9 to 0.961 (P = 0.002).

CONCLUSIONS

We identified a significant decrease of the plasma CXCL7 level in patients with pancreatic cancer, and combination of CA19-9 with CXCL7 improved the discriminatory power of the former for pancreatic cancer.

IMPACT

The present findings may provide a new diagnostic option for pancreatic cancer and facilitate early detection of the disease.

TP53 R72P and MDM2 SNP309 polymorphisms and colorectal cancer risk: the Fukuoka Colorectal Cancer Study

OBJECTIVE

Tumor protein p53 gene and its negative regulator, murine double minute 2 homolog are important components for cell-cycle arrest and apoptosis. An arginine-to-proline substitution at codon 72 in the p53 gene is reported to decrease apoptotic potential, while a thymine-to-guanine polymorphism at nucleotide 309, named SNP309, of murine double minute 2 gene increases transcription of the gene. These two polymorphisms therefore may be of importance in colorectal carcinogenesis. The relation of these polymorphisms to colorectal cancer risk was addressed in the Fukuoka Colorectal Cancer Study.

METHODS

We genotyped the two polymorphisms in 685 incident cases of colorectal cancer and 778 community controls by the polymerase chain reaction-restriction fragment length polymorphism method. Statistical adjustment was made for sex and age.

RESULTS

The proline allele of p53 gene and the guanine allele of SNP309 were each associated with a small, statistically non-significant increase in the odds ratio of colorectal cancer; the adjusted odds ratio (95% confidence interval) for arginine/proline and proline/proline genotypes combined versus arginine/arginine genotype of p53 gene was 1.23 (0.99-1.52) and that for thymine/guanine and guanine/guanine genotypes combined versus thymine/thymine genotype of SNP309 was 1.27 (0.98-1.63). Individuals harboring the proline allele of p53 gene and the guanine allele of SNP309 showed an odds ratio of 1.67 (95% confidence interval, 1.11-2.51).

CONCLUSIONS

Codon 72 polymorphism of p53 and SNP309 in combination may confer an increased risk of colorectal cancer.

Dietary fiber, source foods and colorectal cancer risk: the Fukuoka Colorectal Cancer Study

OBJECTIVE

Despite much evidence from laboratory work, epidemiological evidence remains elusive regarding the role of dietary fiber in colorectal carcinogenesis. We investigated associations of dietary fiber and source foods with colorectal cancer risk in the Fukuoka Colorectal Cancer Study, a community-based case-control study.

MATERIAL AND METHODS

The study subjects were 816 incident cases of colorectal cancer and 815 community controls. Nutrient and food intakes were estimated on the basis of a computer-assisted interview regarding 148 dietary items. Odds ratios of colorectal cancer according to quintile categories of energy-adjusted intakes of dietary fiber and food groups were obtained with adjustment for non-dietary factors and dietary intakes of calcium and n-3 fatty acids.

RESULTS

Total, soluble and insoluble dietary fibers were not measurably associated with overall risk or subsite-specific risk of colorectal cancer. By contrast, rice consumption was associated with a decreased risk of colorectal cancer (trend p = 0.03), particularly of distal colon and rectal cancer (trend p = 0.02), and high intake of non-rice cereals tended to be related to an increased risk of colon cancer (trend p = 0.07). There was no association between vegetable consumption and colorectal cancer, whereas individuals with the lowest intake of fruits tended to have an increased risk of colorectal cancer.

CONCLUSIONS

The present study did not corroborate a protective association between dietary fiber and colorectal cancer, but suggested a decreased risk of distal colorectal cancer associated with rice consumption.

Cigarette smoking, genetic polymorphisms and colorectal cancer risk: the Fukuoka Colorectal Cancer Study

Background

It is uncertain whether smoking is related to colorectal cancer risk. Cytochrome P-450 CYP1A1, glutathione-S-transferase (GST) and NAD(P)H:quinone oxidoreductase 1 (NQO1) are important enzymes in the metabolism of tobacco carcinogens, and functional genetic polymorphisms are known for these enzymes. We investigated the relation of cigarette smoking and related genetic polymorphisms to colorectal cancer risk, with special reference to the interaction between smoking and genetic polymorphism.

Methods

We used data from the Fukuoka Colorectal Cancer Study, a population-based case-control study, including 685 cases and 778 controls who gave informed consent to genetic analysis. Interview was conducted to assess lifestyle factors, and DNA was extracted from buffy coat.

Results

In comparison with lifelong nonsmokers, the odds ratios (OR) of colorectal cancer for <400, 400-799 and ≥800 cigarette-years were 0.65 (95% confidence interval [CI], 0.45-0.89), 1.16 (0.83-1.62) and 1.14 (0.73-1.77), respectively. A decreased risk associated with light smoking was observed only for colon cancer, and rectal cancer showed an increased risk among those with ≥400 cigarette-years (OR 1.60, 95% CI 1.04-2.45). None of the polymorphisms under study was singly associated with colorectal cancer risk. Of the gene-gene interactions studied, the composite genotype of CYP1A1*2A or CYP1A1*2C and GSTT1 polymorphisms was associated with a decreased risk of colorectal cancer, showing a nearly statistically significant (P_interaction = 0.06) or significant interaction (P_interaction = 0.02). The composite genotypes of these two polymorphisms, however, showed no measurable interaction with cigarette smoking in relation to colorectal cancer risk.

Conclusions

Cigarette smoking may be associated with increased risk of rectal cancer, but not of colon cancer. The observed interactions between CYP1A1 and GSTT1 polymorphisms warrant further confirmation.

Assessment of islet quality following international shipping of more than 10,000 km

Islet transplantation is an attractive therapy for type 1 diabetes, although some issues remain. One of them is the severe donor shortage in some countries. In this study, we investigated the possibility of international islet shipping beyond 10,000 km to supply islets to countries with donor shortages. Human islets were isolated from six cadaver donors and cultured until shipment. Islets were packed in either gas-permeable bags or in non-gas-permeable bags and shipped from Baylor Research Institute (Dallas, TX, USA) to Fukuoka University (Fukuoka, Japan). Pre- and postshipment islet number, purity, viability, and stimulation index (by glucose stimulation test) were assessed. Shipped 1,500 IE islets were transplanted into streptozotocin-induced diabetic nude mice for in vivo assay. The distance of our shipment was 11,148.4 km, and the mean duration of the shipments was 48.2 ± 8.2 h. The islet number recovery rate (postshipment/preshipment) was significantly higher in gas-permeable bags (56.4 ± 10.1% vs. 20.5 ± 20.6%, p < 0.01). Islet purity was significantly reduced during shipment in non-gas-permeable bags (from 47.7 ± 18.6% to 40.2 ± 28.2 in gas-permeable bags vs. from 50.4 ± 6.4% to 25.9 ± 15.6% in non-gas-permeable bags, p < 0.05). Islet viability and stimulation index did not change significantly between pre- and postshipping, in either gas-permeable bags or in non-gas-permeable bags. One of three diabetic nude mice (33.3%) converted to normoglycemia. It is feasible to ship human islet cells internationally in gas-permeable bags. This strategy would promote basic and preclinical research for countries with donor shortages, even though the research centers are remote (over 10,000 km from the islet isolation center).

High-mobility group box 1 is involved in the initial events of early loss of transplanted islets in mice

Islet transplantation for the treatment of type 1 diabetes mellitus is limited in its clinical application mainly due to early loss of the transplanted islets, resulting in low transplantation efficiency. NKT cell-dependent IFN-gamma production by Gr-1(+)CD11b(+) cells is essential for this loss, but the upstream events in the process remain undetermined. Here, we have demonstrated that high-mobility group box 1 (HMGB1) plays a crucial role in the initial events of early loss of transplanted islets in a mouse model of diabetes. Pancreatic islets contained abundant HMGB1, which was released into the circulation soon after islet transplantation into the liver. Treatment with an HMGB1-specific antibody prevented the early islet graft loss and inhibited IFN-gamma production by NKT cells and Gr-1(+)CD11b(+) cells. Moreover, mice lacking either of the known HMGB1 receptors TLR2 or receptor for advanced glycation end products (RAGE), but not the known HMGB1 receptor TLR4, failed to exhibit early islet graft loss. Mechanistically, HMGB1 stimulated hepatic mononuclear cells (MNCs) in vivo and in vitro; in particular, it upregulated CD40 expression and enhanced IL-12 production by DCs, leading to NKT cell activation and subsequent NKT cell-dependent augmented IFN-gamma production by Gr-1(+)CD11b(+) cells. Thus, treatment with either IL-12- or CD40L-specific antibody prevented the early islet graft loss. These findings indicate that the HMGB1-mediated pathway eliciting early islet loss is a potential target for intervention to improve the efficiency of islet transplantation.

Prolyl 4-hydroxylation of alpha-fibrinogen: a novel protein modification revealed by plasma proteomics

Plasma proteome analysis requires sufficient power to compare numerous samples and detect changes in protein modification, because the protein content of human samples varies significantly among individuals, and many plasma proteins undergo changes in the bloodstream. A label-free proteomics platform developed in our laboratory, termed "Two-Dimensional Image Converted Analysis of Liquid chromatography and mass spectrometry (2DICAL)," is capable of these tasks. Here, we describe successful detection of novel prolyl hydroxylation of alpha-fibrinogen using 2DICAL, based on comparison of plasma samples of 38 pancreatic cancer patients and 39 healthy subjects. Using a newly generated monoclonal antibody 11A5, we confirmed the increase in prolyl-hydroxylated alpha-fibrinogen plasma levels and identified prolyl 4-hydroxylase A1 as a key enzyme for the modification. Competitive enzyme-linked immunosorbent assay of 685 blood samples revealed dynamic changes in prolyl-hydroxylated alpha-fibrinogen plasma level depending on clinical status. Prolyl-hydroxylated alpha-fibrinogen is presumably controlled by multiple biological mechanisms, which remain to be clarified in future studies.

Genetic polymorphisms of CYP2E1 and risk of colorectal cancer: the Fukuoka Colorectal Cancer Study

Cytochrome P450 2E1 (CYP2E1) is involved in the metabolic activation of a wide variety of potential carcinogens, and functional polymorphisms in the CYP2E1 gene have been investigated in relation to colorectal cancer. We examined the relation of the CYP2E1 RsaI and 96-bp insertion polymorphisms to colorectal cancer risk and the interaction between these polymorphisms and some lifestyle risk factors. Subjects were 685 incident cases of colorectal cancer and 778 community controls. Statistical adjustment was made for alcohol use, body mass index, physical activity, and other factors. The RsaI c2 allele was associated with a decreased risk of rectal cancer [adjusted odds ratio for at least one c2 allele, 0.71; 95% confidence interval (95% CI), 0.53-0.95], and an increased risk of rectal cancer was observed among individuals having one or two 96-bp insertion alleles (adjusted odds ratio, 1.40; 95% CI, 1.06-1.85). Individuals with two 96-bp insertion alleles showed a 2.28-fold increase in colon cancer risk (95% CI, 1.29-4.01). The two polymorphisms were in almost complete linkage disequilibrium (D' = 0.94). A positive association between alcohol intake and colorectal cancer was observed only in individuals without RsaI c2 allele (P(trend) = 0.03) or in those without 96-bp insertion allele (P(trend) = 0.009). Colon cancer risk was increased in relation to red meat intake only in individuals having one or two 96-bp insertion alleles (P(interaction) = 0.03). The present study suggests that variation in activity and inducibility of CYP2E1, in relation to alcohol or red meat intake, contributes to the development of colorectal cancer.

Calcium, dairy foods, vitamin D, and colorectal cancer risk: the Fukuoka Colorectal Cancer Study

Epidemiologic evidence supporting a protective role of calcium and vitamin D in colorectal carcinogenesis has been accumulating in Western populations, but it is limited in Asian populations, whose intake of calcium is relatively low. We investigated the association of intakes of these nutrients with colorectal cancer risk in Japanese. Study subjects were participants of a large-scale case-control study in Fukuoka, Japan. Diet was assessed through interview regarding 148 dietary items by showing typical foods or dishes on the display of a personal computer. In a multivariate analysis adjusting for potential confounding variables, calcium intake was significantly, inversely associated with colorectal cancer risk (P for trend=0.01); the odds ratio for the highest versus lowest quintile of calcium intake was 0.64 (95% confidence interval, 0.45-0.93). Higher levels of dietary vitamin D were significantly associated with decreased risk of colorectal cancer among those who had fewer chances of sunlight exposure at work or in leisure (P for trend=0.02). A decreased risk of colorectal cancer associated with high calcium intake was observed among those who had higher levels of vitamin D intake or among those who had a greater chance of daily sunlight exposure, but not among those with medium or lower intake of vitamin D or among those with potentially decreased sunlight exposure. These results add to support for a joint action of calcium and vitamin D in the prevention of colorectal carcinogenesis.

Colorectal polypectomy and risk of colorectal cancer by subsite: the Fukuoka Colorectal Cancer study

BACKGROUND

Colorectal adenomas are well-established precursor lesions for colorectal cancer and removal of polyps is deemed to reduce the risk of colorectal cancer. However, benefit of colorectal polypectomy in routine practice is still uncertain. We therefore investigated subsite-specific risks of colorectal cancer in relation to history of colorectal polypectomy in a case-control study.

METHODS

Both case patients and control subjects were residents aged 20-74 years in Fukuoka City and three adjacent areas. The case group comprised 840 patients undergoing surgery for a first diagnosis of colorectal cancer, while the control subjects were 833 residents who were selected in the community by two-stage random sampling. Past history of selected diseases, surgery and lifestyle factors were ascertained by in-person interview. Statistical adjustment was made for sex, 5-year age class, residence, smoking, alcohol drinking, physical activity, body mass index and parental history of colorectal cancer.

RESULTS

Overall, 74 case patients (9%) and 85 control subjects (10%) reported a prior history of colorectal polyps, and 50 cases (6%) and 64 controls (8%) had a history of colorectal polypectomy. The adjusted odds ratio associated with colorectal polypectomy was 0.71 (95% confidence interval [CI] 0.48-1.06) for the overall risk of colorectal cancer. The corresponding values for cancer of the proximal colon, distal colon, and rectum were 1.68 (95% CI 0.98-2.88), 0.71 (95% CI 0.41-1.26) and 0.24 (95% CI 0.11-0.52), respectively.

CONCLUSIONS

The findings indicate that colorectal polypectomy in current practice confers a decreased risk of rectal cancer and possibly of distal colon cancer.

Alcohol dehydrogenase and aldehyde dehydrogenase polymorphisms and colorectal cancer: the Fukuoka Colorectal Cancer Study

Alcohol dehydrogenase and aldehyde dehydrogenase are key enzymes in alcohol metabolism and therefore may be of importance to colorectal cancer development. The present case-control study was conducted to determine the influence of ADH2, ADH3 and ALDH2 polymorphisms in Fukuoka, Japan, with 685 incident cases of histologically confirmed colorectal adenocarcinomas and 778 community controls selected randomly from the study area. Alcohol use was ascertained by in-person interview. Statistical adjustment was made for sex, age class, area, and alcohol use. Individuals with the allele 47Arg of the ADH2 polymorphism (slow metabolizers) had a statistically significant increase in risk, with an adjusted OR of 1.32 (95% CI = 1.07-1.63), compared with those having the ADH2*47His/His genotype. This association was not affected by the level of alcohol consumption. The ADH3 polymorphism showed no measurable association with the risk of colorectal cancer on either overall analysis or stratified analysis with alcohol use. The heterozygous ALDH2*487Glu/Lys genotype was not associated with an increase in the risk of colorectal cancer (adjusted OR 0.89, 95% CI = 0.71-1.13) compared with the ALDH2*487Glu/Glu genotype. Rather unexpectedly, the homozygous ALDH2*487Lys/Lys genotype was related to a statistically significantly decreased risk of colorectal cancer (adjusted OR 0.55, 95% CI = 0.33-0.93). It is unlikely that acetaldehyde metabolism determined by ALDH2 polymorphism contributes to the risk of colorectal cancer, whereas the role of ADH2 polymorphism deserves further investigation.

Successful Islet Transplantation to Two Recipients From a Single Donor by Targeting Proinflammatory Cytokines in Mice

BACKGROUND

Currently, the inability to achieve successful islet transplantation from one donor to one recipient is a major obstacle facing clinical islet transplantation. We herein determined whether this limitation could be overcome by targeting pro-inflammatory cytokines with the prevention of immediate islet graft loss in association with engraftment in mice.

METHODS

Isolated islets were grafted into the liver of streptozotocin-induced diabetic mice and the role of proinflammatory cytokines in the engraftment of islets was evaluated with the use of interferon (IFN)-gamma-/- mice and monoclonal antibodies against proinflammatory cytokines.

RESULTS

Hyperglycemia in streptozotocin-induced diabetic mice receiving 200 syngenic islets, which were isolated from a single mouse pancreas, was ameliorated when IFN-gamma-/-, but not wild-type mice, were used as recipients. The treatment with anti-IFN-gamma antibody produced normoglycemia in diabetic wild-type mice receiving 200, but not 100 islets. However, when anti-tumor necrosis factor-alpha and anti-interleukin-1beta antibodies were administered in conjunction with anti-IFN-gamma antibody, wild-type diabetic mice receiving 100 islets became normoglycemic after transplantation. In addition, the favorable effect of the combined use of antibodies was similarly achieved in mice receiving islet allografts when rejection was prevented with anti-CD4 antibody treatment.

CONCLUSIONS

These findings clearly demonstrate that successful islet transplantation from one donor to two recipients is feasible by targeting pro-inflammatory cytokines in mice, thus suggesting a potential application in clinical islet transplantation if similar mechanisms of islet graft loss could be mediated in humans.

Meat, fish and fat intake in relation to subsite-specific risk of colorectal cancer: The Fukuoka Colorectal Cancer Study

High intake of red meat has been associated with increased risk of colorectal cancer in Western countries. There has been much interest in the role of n-3 polyunsaturated fatty acids (PUFA) in colorectal cancer prevention, but epidemiological findings are limited and inconsistent. The objective of our study was to examine associations of meat, fish and fat intake with risk of colorectal cancer, paying particular attention to the subsite within the colorectum. Data were from the Fukuoka Colorectal Cancer Study, a population-based case-control study, covering 782 cases and 793 controls. Diet was assessed by interview, using newly developed personal-computer software for registering semiquantitative food frequencies. The intake of beef/pork, processed meat, total fat, saturated fat or n-6 PUFA showed no clear association with the overall or subsite-specific risk of colorectal cancer. There was an almost significant inverse association between n-3 PUFA and the risk of colorectal cancer; the covariate-adjusted odds ratio for the highest (median 3.94 g/day) versus lowest (median 1.99 g/day) quintile of energy-adjusted intake was 0.74 (95% confidence interval 0.52-1.06, trend P=0.050). The consumption of fish and fish products was similarly inversely related to the risk although the association was not statistically significant. These associations were more evident for distal colon cancer; adjusted odds ratio for the highest versus lowest quintile of n-3 PUFA intake was 0.56 (95% confidence interval 0.34-0.92, trend P=0.02). Our findings do not support the hypothesis that consumption of red meat increases colorectal cancer risk but do suggest that high intake of fish may decrease the risk, particularly of distal colon cancer.

Balloon-catheter endoscopic retrograde pancreatography-compression study for diagnosis of early-stage pancreatitis

Endoscopic retrograde pancreatography (ERP) is considered by many as the gold standard imaging method in the diagnosis of chronic pancreatitis (CP). However, conventional ERP usually has a limited ability to accurately diagnose early-stage CP, in which only the branch ducts are involved and the main pancreatic duct (MPD) is unaffected. To visualize precisely the branch ducts, we have developed a more sophisticated ERP method, called balloon ERP-compression study (balloon ERP-CS). In this procedure, a catheter equipped with a balloon at its tip is placed first into the MPD via the papilla with the aid of conventional ERP, followed by the removal of the endoscope, leaving the catheter behind. Then, the balloon is inflated, and the contrast medium is injected slowly. The balloon serves to block the back flow of the injected contrast medium from the MPD to the duodenum, enabling visualization of the branch ducts. The compression study affords further precise pancreatography of the corresponding area. Thus, balloon ERP-CS has now become an essential procedure for diagnosis of pancreatic lesions, including CP. So far (April 1984 to April 2005), we have performed the procedure in 1012 cases, for a total of 1562 examinations. In this study, we focus on the role of balloon ERP-CS in diagnosis of early-stage CP to elucidate its characteristic features in association with histological findings. This presentation will clarify the usefulness as well as the limitations of balloon ERP-CS for the diagnosis of CP, especially cases without the involvement of the MPD.

Regulatory Roles of NKT Cells in the Induction and Maintenance of Cyclophosphamide-Induced Tolerance

We have previously reported the sequential mechanisms of cyclophosphamide (CP)-induced tolerance. Permanent acceptance of donor skin graft is readily induced in the MHC-matched and minor Ag-mismatched recipients after treatment with donor spleen cells and CP. In the present study, we have elucidated the roles of NKT cells in CP-induced skin allograft tolerance. BALB/c AnNCrj (H-2(d), Lyt-1.2, and Mls-1(b)) wild-type (WT) mice or Valpha14 NKT knockout (KO) (BALB/c) mice were used as recipients, and DBA/2 NCrj (H-2(d), Lyt-1.1, and Mls-1(a)) mice were used as donors. Recipient mice were primed with 1 x 10(8) donor SC i.v. on day 0, followed by 200 mg/kg CP i.p. on day 2. Donor mixed chimerism and permanent acceptance of donor skin allografts were observed in the WT recipients. However, donor skin allografts were rejected in NKT KO recipient mice. In addition, the donor reactive Vbeta6(+) T cells were observed in the thymus of a NKT KO recipient. Reconstruction of NKT cells from WT mice restored the acceptance of donor skin allografts. In addition, donor grafts were partially accepted in the thymectomized NKT KO recipient mice. Furthermore, the tolerogen-specific suppressor cell was observed in thymectomized NKT KO recipient mice, suggesting the generation of regulatory T cells in the absence of NTK cells. Our results suggest that NKT cells are essential for CP-induced tolerance and may have a role in the establishment of mixed chimerism, resulting in clonal deletion of donor-reactive T cells in the recipient thymus.

Physical activity and colorectal cancer: the Fukuoka Colorectal Cancer Study

The number of cases of colorectal cancer in Japan has increased over the past few decades, and incidence rates are now among the highest in the world. The present investigation within the Fukuoka Colorectal Cancer Study, including 778 cases and 767 controls aged 20-74 years, examined the association between physical activity and colorectal cancer risk by subsite. Employment-associated and leisure time physical activity was assessed by a questionnaire and interview. Division of sites into the proximal and distal colon, as well as the rectum, revealed clear site-dependent protective effects, with adjustment for smoking, alcohol consumption, BMI and age. In males, greater job-related physical activity was associated with significant reduction of risk in the distal colon and rectum (P = 0.047 and 0.02, respectively), whereas total and moderate or hard non-job physical activity exerted effects limited to the rectum (P = 0.01 and 0.004, respectively). In females, job-related physical activity and moderate or hard non-job physical activity was also protective, but only in the distal colon. Separate assessment of the influence of BMI 10 years previous to the study showed increase in risk with obesity in males but not in females, limited to distal colon and rectum. The results of the present study indicate that physical activity associated with work and leisure-time exerts beneficial effects in Japanese, but not on the proximal colon.

Natural killer T-cells participate in rejection of islet allografts in the liver of mice

A role of natural killer T (NKT) cells in transplant rejection remains unknown. Here, we determined whether NKT cells participate in rejection of islet allografts, using NKT cell-deficient mice. Survival of islet allografts in streptozotocin-induced diabetic CD1d(-/-) mice or Valpha14 NKT cell(-/-) mice was significantly prolonged without immunosuppression when grafted into the liver, but not beneath the kidney capsule, compared with wild-type mice. Acceptance of intrahepatic islet allografts was achieved in CD1d(-/-) mice by a subtherapeutic dose of rapamycin, which was abrogated in conjunction with the transfer of hepatic mononuclear cells from wild-type, but not from CD1d(-/-), mice at islet transplantation. The second islet grafts from a donor-specific, but not from a third-party, strain in CD1d(-/-) mice bearing functional islet allografts were accepted without immunosuppression at 120 days after the initial transplantation. These findings demonstrate that NKT cells play a significant role in rejection of islet allografts in the liver of mice, but that NKT cells are not essential for induction of donor-specific unresponsiveness in this model. The current study indicates that NKT cells might be considered as a target for intervention to prevent islet allograft rejection when the liver is the site of transplantation.

The Start of an Islet Transplantation Program in Japan

In Japan, pancreas donation had become possible from cadaveric donor sources, both heart-beating or non-heart-beating (NHB). Pancreas allografts have been distributed in the organ allocation system of the Japan Organ Transplant Network. Meanwhile, islet transplantation has been categorized as a tissue transplantation; it is free from legal restraints. Thus, pancreata for islet isolation must be obtained from NHB donors. Herein we report the starting program and preliminary results of islet transplantation in Japan. Selection and listing criteria for transplantation include regional priority, ABO blood type, previous islet transplant status with insulin independence, and a longer waiting time. Five institutes in Japan (Fukushima, Chiba, Kyoto, Kobe, and Fukuoka) are prepared to start programs. A two-layer cold storage method using perfluorocarbons and UW solution is recommended for pancreas preservation. Islet isolation and purification procedures are performed according to institute-specific protocol. Immunosuppression is based on sirolimus/tacrolimus combined with basiliximab induction. Two or three consecutive infusions of >5000 IE/kg are planned for each recipient until achieving insulin independence. Twenty-seven isolations and 14 transplants were performed in eight non-insulin-dependent diabetes mellitus (IDDM) recipients. Almost all (26 of 27) were NHB donors. All recipients are free from hypoglycemic episode after transplantation. One of these recipients is insulin independent; the others are currently on minimal doses of exogenous insulin. The feasibility of islet transplantation using NHB donors was confirmed using a two-layer cold storage method and a steroid-free immunosuppressive protocol, with a high rate of graft function.

Valpha14 NK T cell-triggered IFN-gamma production by Gr-1+CD11b+ cells mediates early graft loss of syngeneic transplanted islets

Pancreatic islet transplantation is a highly promising approach for the treatment of insulin-dependent diabetes mellitus. However, the procedure remains experimental for several reasons, including its low efficiency caused by the early graft loss of transplanted islets. We demonstrate that Gr-1⁺CD11b⁺ cells generated by transplantation and their IFN-γ production triggered by Vα14 NKT cells are an essential component and a major cause of early graft loss of pancreatic islet transplants. Gr-1⁺CD11b⁺ cells from Vα14 NKT cell–deficient (Jα281^−/−) mice failed to produce IFN-γ, resulting in efficient islet graft acceptance. Early graft loss was successfully prevented through the repeated administration of α-galactosylceramide, a specific ligand for Vα14 NKT cells, resulting in dramatically reduced IFN-γ production by Gr-1⁺CD11b⁺ cells, as well as Vα14 NKT cells. Our study elucidates, for the first time, the crucial role of Gr-1⁺CD11b⁺ cells and the IFN-γ they produce in islet graft rejection and suggests a novel approach to improving transplantation efficiency through the modulation of Vα14 NKT cell function.

Intraductal Tubular Adenoma of the Pancreas, Pyloric Gland Type

The intraductal tubular adenoma (ITA), pyloric gland type, of the pancreas is an uncommon benign tumor, akin to the pyloric gland type adenoma of the gallbladder. We report 6 cases of ITA of the pancreas: 3 male and 3 female aged 50 to 79 years (mean, 63.5 years; median, 65 years); all were examined clinicopathologically. Four patients showed no symptoms, but appetite loss and/or general fatigue presented in two. Grossly, all tumors formed a localized polypoid mass protruding into the lumen of the dilated pancreatic duct. Five of the six tumors were found within the main duct, and the other arose within the branch duct of the pancreas. Microscopically, the tumors were composed of closely packed tubular glands resembling pyloric type glands. They were lined by columnar or cuboidal epithelial cells with foci of mild to moderate dysplastic change. In 2 cases, the adjacent pancreas showed foci of intraductal papillary-mucinous adenoma. Histochemically, the tumors largely showed neutral mucin with a lesser amount of acidic mucin made up mainly of sialomucin. Endocrine cells were found in five tumors. Immunohistochemically, all tumors were labeled with M-GGMC-1 and MUC6, whereas MUC1 and MUC2 stains were negative. Pepsinogen II was positive in 5 tumors; thus, the results displayed a pattern of differentiation similar to those of ordinary gastric pyloric or metaplastic pyloric glands. DPC4 expression was maintained in all tumors and p53-positive nuclei were hardly encountered. All patients are alive with no evidence of disease 3 to 10.5 years after surgical resection.

cDNA microarray analysis after laser microdissection in proliferating islets of partially pancreatectomized mice

With islet transplantation having grown in popularity since the introduction of the Edmonton protocol, how to secure an unlimited source of islets has become an urgent problem. To resolve this problem, techniques to induce or proliferate islets are urgently required. To achieve this goal, gene expression analysis using a cDNA microarray in islets of partially pancreatectomized mice, in which the remaining islets regenerate and proliferate with insulin secretion and glucose responsiveness, provides us with valuable information. However, those experiments have two critical problems: first, how to selectively collect the regenerating or proliferating islets, and second, the shortage of total RNA extracted from one islet for a microarray analysis. A useful system was thus designed which combined laser microdissection, cDNA amplification by SMART PCR, which can maintain the relative expression profile of transcripts throughout reactions, and a cDNA microarray. Furthermore, this system is expected to contribute to future studies regarding not only islet regeneration but also the function of the islet itself, and this system may also be applicable to many other types of endocrine tissue. In this review, the details of this system are presented and discussed.

Methylenetetrahydrofolate reductase C677T and A1298C polymorphisms and colorectal cancer: the Fukuoka Colorectal Cancer Study

Methylenetetrahydrofolate reductase (MTHFR) is a key enzyme regulating folate metabolism, which affects DNA synthesis and methylation. This study investigated the relation of MTHFR C677T and A1298C polymorphisms to colorectal cancer in a case-control study in Fukuoka, Japan. The subjects comprised 685 incident cases of histologically confirmed colorectal adenocarcinomas and 778 community controls selected randomly in the study area. The genotype was determined by the PCR-RFLP method using genomic DNA extracted from buffy coat. Alcohol use was ascertained by in-person interview. Statistical adjustment was made for gender, age class, area, and alcohol use. The MTHFR 677TT genotype was associated with a statistically significant decrease in the risk with an adjusted odds ratio of 0.69 (95% confidence interval 0.51-0.93) compared with the 677CC and 677CT combined, and the decrease was most evident in individuals with no alcohol consumption. While the A1298C polymorphism showed no measurable association with the overall risk of colorectal cancer, the 1298CC genotype was associated with a statistically significant increase in the risk when alcohol consumption was high, and was also associated with an approximately 2-fold increase in the risk of each of proximal and distal colon cancer. The findings add to evidence that individuals with the MTHFR 677TT genotype have a decreased risk of colorectal cancer in the absence of folate depletion, suggesting a protective role of folate by ensuring a sufficient thymidylate pool for DNA synthesis. Because very few individuals had the 1298CC genotype, the findings regarding the A1298C polymorphism need careful interpretation and confirmation in larger studies.

Beneficial Effects of Costimulatory Blockade with Anti-Inducible Costimulator Antibody in Conjunction with CTLA4Ig on Prevention of Islet Xenograft Rejection from Rat to Mouse

BACKGROUND

Costimulatory signals have been reported to play an important role in islet-xenograft rejection, although the precise mechanisms remain unknown. The aim of the present study was to determine a role of a novel costimulatory molecule, inducible costimulator (ICOS), in rat islet-xenograft rejection in conjunction with CTLA4Ig with respect to cellular as well as humoral immune responses.

METHODS

Isolated rat islets were transplanted into the liver of streptozotocin (180 mg/kg) induced diabetic mice. Cellular immune responses to islet xenografts, and productions of anti-rat antibody in mice were examined by flow cytometry (FACS) after transplantation.

RESULTS

Intrahepatic rat islet xenografts were rejected in mice within 8 days after transplantation. FACS analysis revealed an expansion of CD8(+) T cells in the liver as well as a production of anti-rat antibody in recipient mice in association with rejection. The treatment with anti-ICOS antibody in conjunction with CTLA4Ig produced a marked prolongation of islet-xenograft survival with neither expansion of CD8(+) T cells nor production of anti-rat antibody, whereas, in contrast, those treated with anti-ICOS antibody or CTLA4Ig alone did not have prolonged survival, and CD8(+) T cells were expanded.

CONCLUSION

These findings demonstrate that cellular rather than humoral immune responses are considered responsible for islet-xenograft rejection from rat to mouse and that the blockade of costimulatory signals with anti-ICOS antibody in conjunction with CTLA4Ig has a favorable effect on prevention of islet xenograft rejection.

Amelioration of hyperglycemia in streptozotocin-induced diabetic mice with fetal pancreatic allografts: prevention of rejection by donor specific transfusion in conjunction with CTLA4Ig

INTRODUCTION

Fetal pancreas has been considered as an alternative donor source for islet transplantation since it has potent capacity for beta cell differentiation and proliferation. However, prevention of fetal pancreatic allograft rejection can be hardly achieved compared with adult islet allografts.

AIMS

The aim of the study is to determine whether donor specific transfusion (DST) in conjunction with CTLA4Ig has any favorable effect on prevention of fetal pancreatic allograft rejection in mice.

METHODS

BALB/c splenocytes (SPC, 1 x 10) were injected iv into C57BL/6 mice in conjunction with CTLA4Ig (ip, 50 microgram, day 0, 2, and 4). Fourteen days later, the mice were made diabetic with streptozotocin (STZ, iv) and donor specific or third party pancreatic allografts were transplanted beneath the kidney capsule.

RESULTS

Morphologically, it was found that rejection of fetal pancreatic allografts can be prevented at 30 days after transplantation only when donor specific allografts were grafted into the mice treated with DST in conjunction with CTLA4Ig. Functionally, 3 out of 9 diabetic mice became normoglycemic by 120 days after transplantation of fetal pancreatic allografts.

CONCLUSION

DST in conjunction with CTLA4Ig can have a favorable effect on prevention of fetal pancreatic allograft rejection resulting in amelioration of STZ-induced diabetes in mice.