Katsuyoshi Kudoh

Gastrojejunostomy and Duodenojejunostomy for Megaduodenum in Systemic Sclerosis Sine Scleroderma: Report of a Case

Systemic sclerosis is an autoimmune disease that causes sclerotic changes primarily in the skin and in other organs. Systemic sclerosis sine scleroderma (ssSSc) is a variant of the disease in which visceral involvement occurs in the absence of skin thickening [1]. Most patients with systemic sclerosis have digestive tract complications, 90% of which involve esophageal diseases such as gastroesophageal reflux disease (GERD) and Barrett esophagus [2–6]. The rate of small intestinal complications in systemic sclerosis, although lower than that of esophageal complications, is estimated to be about 50%. In systemic sclerosis, more common small intestinal complications include intestinal pseudoobstruction with dilatation of the small intestine and small intestinal diverticula [1–5]. Megaduodenum is relatively rare as a small

Factors Affecting the Bowel Function after Proctocolectomy and Ileal J Pouch–Anal Anastomosis for Ulcerative Colitis

The aim was to study determinants of postoperative bowel function after restorative proctocolectomy for ulcerative colitis. Medical records of patients who underwent proctocolectomy with ileal J pouch-anal anastomosis (IPAA) in two- or three-stage operations and whose status of defecation was known via a questionnaire were retrospectively reviewed. Bowel function, including stool frequency, stool consistency, and degree of nighttime soiling, was correlated with age at the time of surgery, time after ileostomy closure, mean resting anal pressure, longitudinal length of ileal J pouch, and duration of fecal diversion by using univariate and multivariate analyses. Stool frequency decreased significantly with time after ileostomy closure in both univariate and multivariate analyses. Stool frequency tended to be less in patients having a long J pouch, but the correlation was not significant (P=0.071) in univariate analysis. Nighttime soiling ameliorated with time after ileostomy closure in multivariate, but not univariate, analysis. Deterioration of nighttime soiling was seen in patients whose duration for fecal diversion was long, both in univariate (P=0.068) and multivariate (P=0.052) analyses. Stool consistency was related to none of the five factors investigated. These results indicate that as the time after surgery increases, stool frequency decreases and nighttime soiling ameliorates. Delaying ileostomy closure because of anticipated postoperative incontinence does not significantly alter postoperative continence.

Synthetic Analogs of Curcumin Modulate the Function of Multidrug Resistance–Linked ATP-Binding Cassette Transporter ABCG2

Multidrug resistance (MDR) caused by the overexpression of ATP-binding cassette (ABC) transporters in cancer cells is a major obstacle in cancer chemotherapy. Previous studies have shown that curcumin, a natural product and a dietary constituent of turmeric, inhibits the function of MDR-related ABC transporters, including ABCB1, ABCC1, and especially ABCG2. However, the limited bioavailability of curcumin prevents its use for modulation of the function of these transporters in the clinical setting. In this study, we investigated the effects of 24 synthetic curcumin analogs with increased bioavailability on the transport function of ABCG2. The screening of the 24 synthetic analogs by means of flow cytometry revealed that four of the curcumin analogs (GO-Y030, GO-Y078, GO-Y168, and GO-Y172) significantly inhibited the efflux of the ABCG2 substrates, mitoxantrone and pheophorbide A, from ABCG2-overexpressing K562/breast cancer resistance protein (BCRP) cells. Biochemical analyses showed that GO-Y030, GO-Y078, and GO-Y172 stimulated the ATPase activity of ABCG2 at nanomolar concentrations and inhibited the photolabeling of ABCG2 with iodoarylazidoprazosin, suggesting that these analogs interact with the substrate-binding sites of ABCG2. In addition, when used in cytotoxicity assays, GO-Y030 and GO-Y078 were found to improve the sensitivity of the anticancer drug, SN-38, in K562/BCRP cells. Taken together, these results suggest that nontoxic synthetic curcumin analogs with increased bioavailability, especially GO-Y030 and GO-Y078, inhibit the function of ABCG2 by directly interacting at the substrate-binding site. These synthetic curcumin analogs could therefore be developed as potent modulators to overcome ABCG2-mediated MDR in cancer cells.

Genotyping Analysis of Bitter-Taste Receptor Genes TAS2R38 and TAS2R46 in Japanese Patients with Gastrointestinal Cancers

Type-2 bitter-taste receptors (TAS2Rs) are important for the evaluation of food quality and the nutritional control in animals. Mutations in some TAS2Rs including TAS2R38 are known to increase susceptibility to various diseases. However, the involvement of TAS2Rs in cancers has not been well understood. We conducted a pilot study by genotyping two TAS2R genes, TAS2R38 and TAS2R46, in Japanese cancer patients diagnosed with the following types of cancer: biliary tract cancer, hepatocellular carcinoma, pancreatic cancer, colorectal cancer and gastric cancer. We selected the two TAS2Rs because they carry virtually non-functional alleles in human populations. We found that cancer risk is not associated with any TAS2R46 genotypes since there were no significant differences in genotype frequencies between cancer patients and controls. On the other hand, we confirmed that phenylthiocarbamide (PTC) non-tasters homozygous (AVI/AVI) for TAS2R38 were more frequent among Japanese cancer patients than those among controls as suggested in a previous study. The AVI/AVI genotype was therefore considered to increases cancer risk. In contrast, we also found that homozygous (PAV/PAV) PTC tasters are less frequent among cancer patients, suggesting that the PAV/PAV is a cancer resistant genotype that decreases cancer risk. Genotype frequencies for heterozygous AVI/PAV genotype were not significantly different between the two groups. It is suggested that the risk and resistance of cancers is antagonistically controlled by the two TAS2R38 alleles, PAV and AVI, rather than by the AVI allele alone.

Lymph nodes around the posterior gastric artery: their existence, frequency, and clinical implications

PurposeThe lymphatic flow along the posterior gastric artery (PGA) is considered of possible clinical importance in terms of lymphatic metastasis; however, little is known about the lymph nodes (LNs) around this artery. The purpose of this study was to establish if LNs exist around the PGA and to evaluate their clinical implications.MethodsWe examined the tissues surrounding the PGA from 21 cadavers to search for LNs. We also investigated the patterns of lymphatic metastases in patients who underwent surgery for gastric neoplasms at our institute to detect their presence along the PGA.ResultsThe PGA was identified in 11 cadavers, and LNs around the PGA were detected microscopically in 2 of these. Lymphatic metastasis directly to the LNs at the splenic artery without any metastases was regarded as skip metastasis along the PGA. Skip metastasis was found in two of ten patients who underwent surgery for remnant gastric cancer.ConclusionsThe existence of LNs around the PGA was confirmed, and based on our findings, lymphatic metastasis through the PGA is possible in patients with remnant gastric cancer.

A novel potent ABCB1 modulator, phenethylisoquinoline alkaloid, reverses multidrug resistance in cancer cell.

ATP-binding cassette (ABC) transporters, which are concerned with the efflux of anticancer drugs from cancer cells, have a pivotal role in multidrug resistance (MDR). In particular, ABCB1 is a well-known ABC transporter that develops MDR in many cancer cells. Some ABCB1 modulators can reverse ABCB1-mediated MDR; however, no modulators with clinical efficacy have been approved. The aim of this study was to identify novel ABCB1 modulators by using high-throughput screening. Of the 5861 compounds stored at Tohoku University, 13 compounds were selected after the primary screening via a fluorescent plate reader-based calcein acetoxymethylester (AM) efflux assay. These 13 compounds were validated in a flow cytometry-based calcein AM efflux assay. Two isoquinoline derivatives were identified as novel ABCB1 inhibitors, one of which was a phenethylisoquinoline alkaloid, (±)-7-benzyloxy-1-(3-benzyloxy-4-methoxyphenethyl)-1,2,3,4-tetrahydro-6-methoxy-2-methylisoquinoline oxalate. The compound, a phenethylisoquinoline alkaloid, was subsequently evaluated in the cytotoxicity assay and shown to significantly enhance the reversal of ABCB1-mediated MDR. In addition, the compound activated the ABCB1-mediated ATP hydrolysis and inhibited the photolabeling of ABCB1 with [125I]-iodoarylazidoprazosin. Furthermore, the compound also reversed the resistance to paclitaxel without increasing the toxicity in the ABCB1-overexpressing KB-V1 cell xenograft model. Overall, we concluded that the newly identified phenethylisoquinoline alkaloid reversed ABCB1-mediated MDR through direct interaction with the substrate-binding site of ABCB1. These findings may contribute to the development of more potent and less toxic ABCB1 modulators, which could overcome ABCB1-mediated MDR.

Oral rehydration solution normalizes plasma renin and aldosterone levels in patients with ulcerative colitis after proctocolectomy

Objectives: The possible effects and benefits of oral rehydration solution (ORS) on chronic dehydration after total proctocolectomy. Methods: To evaluate the effect of ORS on the renin-angiotensin system after remnant proctocolectomy in patients with ulcerative colitis (UC), we selected 20 patients after remnant proctocolectomy, ileal J pouch-anal anastomosis, and construction of a diverting ileostomy for UC. Patients were randomly divided into two groups, A (n=9) or B (n=11), 2 weeks after the surgery. In group A, ORS (1000 mL/day) was given for the first 7 days and mineral water (1000 mL/day) for the next 7 days. In group B, mineral water (1000 mL/day) was given for the first 7 days and ORS (1000 mL/day) for next 7 days. Plasma levels of renin, aldosterone and excretion of sodium in urine were evaluated at days 0, 7, and 14. We defined day 0 as the day of beginning this study. Results: Mean plasma renin levels on day 0 were six to eight times greater than the upper normal limit. In group A, ORS lowered plasma renin levels. In group B, plasma levels of renin and aldosterone after ORS were lower than those at days 0 and 7. Conclusions: ORS corrected increased plasma levels of renin and aldosterone to within the normal range in patients after proctocolectomy.

Abstract 3242: Synthetic analogs of curcumin as modulators of multidrug resistance-linked ABC transporters

Cancer patients often develop resistance to anticancer drugs. ATP-binding cassette (ABC) transporter-mediated drug efflux is one of the mechanisms responsible for development of resistance to anticancer drugs. The present study investigates the use of curcumin, a natural product and a dietary constituent of turmeric, which inhibits the function of three ABC drug transporters including ABCB1, ABCC1 and ABCG2. However, limited bioavailability of curcumin prevents its use for modulation of the function of these transporters in the clinic. We focused on curcumin analogs that were synthesized at Tohoku University and have been shown to exhibit higher bioavailability than natural curcumin to test whether the synthetic analogs also inhibit the function of ABC drug transporters. To investigate this, KB-V1 and K562/BCRP cell lines overexpressing ABCB1 and ABCG2 were used for the experiments. For these studies, we screened nineteen synthetic analogs of curcumin for their effect on the transport function of ABCB1 and ABCG2 by flow cytometry. Four curcumin analogs, GO-Y030, GO-Y078, GO-Y168 and GO-Y172 inhibited efflux of mitoxantrone mediated by ABCG2 and sensitized ABCG2-expressing K562 leukemic cells to the anticancer drug, SN-38 in cell toxicity assays. Some of the curcumin analogs (GO-Y030, GO-Y078, GO-Y172) stimulated ATPase activity of ABCG2 at nanomolar concentrations (EC50 = 480 ± 0.06, 790 ± 0.10, 930 ± 0.12 nM). In addition, GO-Y030, GO-Y078, GO-Y168, GO-Y172 analogs also inhibited photolabeling of ABCG2 in MCF-7-FL plasma membranes with iodoarylazidoprazosin, which is transported by this transporter. These data demonstrate that similar to curcumin, synthetic curcumin analogs also interact at the drug-binding pocket of ABCG2. In aggregate, these results suggest that non-toxic synthetic curcumin analogs with increased bioavailability may be useful to reverse ABCG2-mediated resistance to anticancer agents. Citation Format: Megumi Obara, Shinobu Ohnuma, Eduardo E. Chufan, Masaharu Ishida, Katsuyoshi Kudoh, Norihiko Sugisawa, Hideo Ohtsuka, Takeshi Naitoh, Hiroyuki Shibata, Yoshiharu Iwabuchi, Suresh V. Ambudkar, Michiaki Unno. Synthetic analogs of curcumin as modulators of multidrug resistance-linked ABC transporters [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 3242. doi:10.1158/1538-7445.AM2017-3242

Abstract 5538: Functional analysis of BAP1, de-ubiquitination enzyme, in intrahepatic cholangiocarcinoma

BACKGROUND: BRCA associated protein 1 (BAP1) was discovered as a protein associated with the breast cancer susceptibility gene (BRCA), and genetic mutations of BAP1 gene have recently been found in some malignant tumors, such as melanoma, mesothelioma, and renal cell carcinoma. Since the mutations of BAP1 gene resulted in loss of function of this protein and were associated with poor prognoses of the malignancies, BAP1 is now considered as a tumor-suppressor gene. Recent studies have shown that BAP1 mutations were also observed in patients with intrahepatic cholangiocarcinoma (IHCC), which is one of the most aggressive carcinoma with poor prognoses. However, only a few studies have investigated the role of BAP1 mutation on biological function of tumor cells and on clinicopathological features of IHCC. PURPOSE: The purpose of this study was to elucidate the association of BAP1 and IHCC. METHOD: The expression of BAP1 was immunohistochemically analyzed in surgically resected IHCC specimens, and the cases were classified into three groups based on the result of immunostaining concentration; positive or weakly positive or negative. The clinicopathological factors, such as the disease stage of IHCC, curability and overall survival (OS), were compared among the groups. In cell culture analyses, the expression of BAP1 in IHCC cell lines (HuCC-T1 and TFK-1) was down-regulated by Zinc-finger nuclease (ZFN) and siRNA in vitro. Then, cell-proliferation assay, migration assay, invasion assay, and drug-susceptibility test were performed on BAP1 down-regulated cells. RESULTS: The immunohistochemistry of BAP1 on IHCC specimens showed that OS was not significantly changed among three groups. However, the cases with lower expression of BAP1 including weakly positive and negative tended to be advanced in disease stage compared with cases with BAP1 positive. Interestingly, in the patients received postoperative gemcitabine, a standard chemo-drug for cholangiocarcinoma, cases with lower expression of BAP1 showed prolonged survival compared with cases with BAP1 positive. In cell experiments, the knock-down of BAP1 did not affect cell-proliferation of IHCC cells, however, it promoted migration and invasion of IHCC cells. Furthermore, the suppression of BAP1 enhanced chemosensitivity to gemcitabine. CONCLUSIONS: Our study suggested that lower expression of BAP1 was associates with the progression of IHCC and with enhanced chemosensitivity to gemcitabine. BAP1 might be one of the target genes in the treatment of IHCC. Citation Format: Kentaro Ishii, Masaharu Ishida, Shinobu Ohnuma, Katsuyoshi Kudoh, Fuyuhiko Motoi, Takeshi Naitoh, Florin Selaru, Michiaki Unno. Functional analysis of BAP1, de-ubiquitination enzyme, in intrahepatic cholangiocarcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 5538. doi:10.1158/1538-7445.AM2017-5538

Abstract 2832: Single nucleotide polymorphisms of DPYD and MTHFR predict adverse events associated with 5-fluorouracil in patients with gastrointestinal cancer

Purpose The aim of this study was to investigate the association between 5-fluorouracil (5-FU)-related adverse events (AEs) in Japanese patients with gastrointestinal cancer treated with 5-FU and the patient genotypes DPYD, MTHFR, OPRT, and TYMS. Methods Sequence analyses of 33 gene polymorphisms in four genes were performed using genomic DNA extracted from peripheral blood mononuclear cells of 103 patients with gastric (n = 34) or colorectal (n = 69) cancer. The 5-FU-related AEs of 157 regimens in these 103 patients were evaluated based on the medical records of patients in each of three groups: the intravenous administration group (i.v. group, n = 51), oral administration group (p.o. group, n = 106), and all-regimens group (both i.v. and p.o. group, n = 157). The associations between the incidence of AEs and each genotype were statistically analyzed. Results Six single-nucleotide polymorphisms (SNPs) were identified (three SNPs in DPYD: c.496A>G, c.1905+1G>A, and c.2303C>A; two SNPs in MTHFR: c.677C>T and c.1298A>C; and one SNP in OPRT: c.638G>C). Among them, the patients in the all-regimens group carrying any one of three DPYD SNPs showed statistically significant associations with the incidence of AEs of any type and fatigue. Furthermore, the MTHFR SNP c.1298A>C was significantly associated with the incidence of neutropenia. A similar trend was observed in the p.o. group, but not in the i.v. group. Conclusion These findings suggest that the DPYD SNPs c.496A>G, c.1905+1G>A, and c.2303C>A and the MTHFR SNP c.1298A>C may be predictive factors for the occurrence of severe 5-FU-related AEs. Citation Format: Masahide Toshima, Shinobu Ohnuma, Michiiro Tanaka, Koh Miura, Wataru Fujibuchi, Taiki Kajiwara, Toshihiro Komura, Hiroaki Musha, Sho Haneda, Katsuyoshi Kudoh, Atsushi Kohyama, Takeshi Naitoh, Michiaki Unno. Single nucleotide polymorphisms of DPYD and MTHFR predict adverse events associated with 5-fluorouracil in patients with gastrointestinal cancer. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 2832. doi:10.1158/1538-7445.AM2014-2832