Shin-ichi Chiba

Colonic Vascular Conductance Increased by Daikenchuto via Calcitonin Gene-Related Peptide and Receptor-Activity Modifying Protein 1

BACKGROUND Daikencyuto (DKT) is a traditional Japanese medicine (Kampo) and is a mixture of extract powders from dried Japanese pepper, processed ginger, ginseng radix, and maltose powder and has been used as the treatment of paralytic ileus. DKT may increase gastrointestinal motility by an up-regulation of the calcitonin gene-related peptide (CGRP). CGRP is also the most powerful vasoactive substance. In the present study, we investigated whether DKT has any effect on the colonic blood flow in rats. MATERIALS AND METHODS Experiments were performed on fasted anesthetized and artificially ventilated Wistar rats. Systemic mean arterial blood pressure and heart rate were recorded. Red blood cell flux in colonic blood flow was measured using noncontact laser tissue blood flowmetry, and colonic vascular conductance (CVC) was calculated as the ratio of flux to mean arterial blood pressure. We examined four key physiological mechanisms underlying the response using blocker drugs: CGRP1 receptor blocker (CGRP(8-37)), nitric oxide synthase inhibitor, vasoactive intestinal polypeptide (VIP) receptor blocker ([4-Cl-DPhe6, Leu17]-VIP), and substance P receptor blocker (spantide). Reverse transcription-polymerase chain reaction was used for the detection of mRNA of calcitonin receptor-like receptor, receptor-activity modifying protein 1, the component of CGRP 1 receptor and CGRP. After laparotomy, a cannula was inserted into the proximal colon to administer the DKT and to measure CVC at the distal colon. RESULTS Intracolonal administration of DKT (10, 100, and 300 mg/kg) increased CVC (basal CVC, 0.10 mL/mmHg) from the first 15-min observation period (0.14, 0.17, and 0.17 mL/mmHg, respectively) and with peak response at either 45 min (0.17 mL/mmHg by 10 mg/kg), or 75 and 60 min (0.23 and 0.21 mL/mmHg by 100 and 300 mg/kg, respectively). CGRP(8-37) completely abolished the DKT-induced hyperemia, whereas nitric oxide synthase inhibitor partially attenuated the DKT-induced hyperemia. [4-Cl-DPhe6, Leu17]-VIP and spantide did not affect the hyperemia. Japanese pepper significantly increased CVC at 45 min or later, whereas ginseng radix only showed a significant increase at 15 min. Reverse transcription-polymerase chain reaction showed that mRNA for calcitonin receptor-like receptor, receptor-activity modifying protein 1, and CGRP were expressed in rat colon and up-regulated by DKT. CONCLUSIONS The present study demonstrated that DKT increased CVC, which was mainly mediated by CGRP and its receptor components.

Daikenchuto (TU-100) ameliorates colon microvascular dysfunction via endogenous adrenomedullin in Crohn’s disease rat model

BackgroundDaikenchuto (TU-100), a traditional Japanese medicine, has been reported to up-regulate the adrenomedullin (ADM)/calcitonin gene-related peptide (CGRP) system, which is involved in intestinal vasodilatation. The microvascular dysfunction of the intestine in Crohn’s disease (CD), due to down-regulation of the ADM/CGRP system, is etiologically related to the recurrence of CD. Therefore, we investigated the vasodilatory effect of TU-100 in a CD rat model.MethodsColitis was induced by the rectal instillation of 2,4,6-trinitrobenzenesulfonic acid (TNBS) in rats. Laser Doppler blood flowmetry was used to measure colonic blood flow. ADM, CGRP, and their receptors in the ischemic colon were measured by reverse transcription polymerase chain reaction (RT-PCR) and enzyme immunoassays. Additionally, we determined whether the intestinal epithelial cell line IEC-6 released ADM in response to TU-100.ResultsTU-100 increased blood flow in ischemic segments of the colon but not in hyperemic segments. Pretreatment with an antibody to ADM abolished the vasodilatory effect of TU-100. CGRP levels and βCGRP mRNA expression were decreased in the ischemic colon, while protein and mRNA levels of ADM were unchanged. Hydroxy α-sanshool, the main constituent of TU-100, was the most active component in improving blood flow. Additionally, both TU-100 and hydroxy α-sanshool enhanced the release of ADM from IEC-6 cells.ConclusionsIn the ischemic colon, endogenous βCGRP, but not ADM, was decreased. Thus, it was concluded that TU-100 ameliorated microvascular dysfunction by the up-regulation of endogenous ADM in the CD rat model. TU-100 may be a possible therapeutic agent for gastrointestinal ischemia-related diseases including CD.

Haplotype analysis of the human collectin placenta 1 (hCL-P1) gene

AbstractCollectins are a family of C-type lectins found in vertebrates. These proteins have four regions, a relatively short N-terminal region, a collagen-like region, an alpha-helical coiled coil, and a carbohydrate recognition domain. Collectins are involved in host defense through their ability to bind carbohydrate antigens on microorganisms. Type A scavenger receptors are classical-type scavenger receptors that also have collagen-like domains. We previously described a new scavenger receptor, collectin from placenta [collectin placenta 1 (CL-P1)]. CL-P1 is a type II membrane protein with all four regions. We found that CL-P1 can bind and phagocytize both bacteria and yeast. In addition to that, it reacts with oxidized low-density lipoprotein (LDL) but not with acetylated LDL. These results suggest that CL-P1 might play important roles in host defenses and/or atherosclerosis formation. One rational strategy to study the role of CL-P1 in these pathological conditions would be to perform a haplotype association study using human samples. As a first step for this strategy, we analyzed the haplotype structure of the CL-P1 gene. By sequencing the CL-P1 gene in ten Japanese volunteers, we identified five single-nucleotide polymorphisms (SNPs) with a minor allele frequency of at least 29%. To obtain SNPs in the 5′-upstream region of the gene, we screened a total of 20 SNPs described in the database and finally picked up one SNP for the present study. Thus, a total of six SNPs, one in the 5′-upstream region, two in intron 2, one in exon 5, and two in exon 6, were used to analyze the haplotype structure of the gene, with DNAs derived from 54 individuals (108 alleles). The analysis revealed that only two of six SNPs showed significant linkage disequilibrium (r2 > 0.5) with each other. This haplotype information may be useful in disease-association studies in which a contribution of the CL-P1 gene has been suspected, especially in immunological disturbance or atherosclerosis. Two SNPs in exon 6, both leading to amino acid substitutions, could be candidates for influencing disease susceptibility.

Tracking the Clonal Evolution of Adenosquamous Carcinoma, a Rare Variant of Intraductal Papillary Mucinous Neoplasm of the Pancreas.

Adenosquamous carcinoma (ASC) is an uncommon variant of pancreatic neoplasm. We sought to trace the mode of tumor progression using specimens of ASC associated with intraductal papillary mucinous neoplasm (IPMN) of the pancreas. A resected specimen of the primary pancreatic ASC, developed in a 72-year-old man, was subjected to mutation profiling using amplicon-targeted sequencing and digital polymerase chain reaction. DNA was isolated from each histological compartment including noninvasive IPMN, squamous cell carcinoma (SCC), and adenocarcinoma (AC). Histologically, an IPMN with a large mural nodule was identified. The invasive tumor predominantly consisted of SCC, and a smaller AC was found around the lesion. Squamous metaplasias were sporadically distributed within benign IPMNs. Mutation alleles KRAS and GNAS were identified in all specimens of IPMN including the areas of squamous metaplasia. In addition, these mutations were found in SCC and AC. Clear transition from flat/low-papillary IPMN to SCC indicated a potent invasion front, and the SCC compartment was genetically unique, because the area has a higher frequency of mutation KRAS. The invasive tumors with distinct histological appearances shared the form of noninvasive IPMN as a common precursor, rather than de novo cancer, suggesting the significance of a genetic profiling scheme of tumors associated with IPMN.

Replacement of liver parenchyma in analbuminemic rats with allogenic hepatocytes is facilitated by intrabone marrow-bone marrow transplantation.

Although hepatocyte transplantation (HCTx) is expected to become a useful therapy for human liver diseases, allogenic hepatocytes still tend to be rejected within a short period due to host immunosurveillance. In the present study, we investigated the effect of prior bone marrow transplantation (BMTx) for the engraftment of allogenic hepatocytes using the analbuminemic rat transplantation model. The hepatocytes of Lewis (LEW) rats were not accepted in the liver of retrorsine (RS)/partial hepatectomy (PH)-treated analbuminemic F344 (F344-alb) rats, which express the disparate major histocompatibility complex (MHC) against that of LEW rats. Prior BMTx with the LEW bone marrow cells (BMCs) after sublethal irradiation achieved acceptance and repopulation of LEW hepatocytes in the liver of the RS/PH-treated F344-alb rats, associated with elevation of serum albumin. The replacement of hepatic parenchyma with albumin positive (Alb+) donor hepatocytes and elevation of serum albumin levels were dependent on the bone marrow reconstitution by donor BMCs, which was more efficiently achieved by intrabone marrow (IBM)-BMTx than by intravenous (IV)-BMTx. Our results demonstrate that efficient bone marrow reconstitution by IBM-BMTx enables the replacement of the hepatic parenchyma with allogenic hepatocytes in RS/PH-treated analbuminemic rats without immunosuppressants.

Abstract 2267: Efficacy of pemetrexed-based chemotherapy in patients with NSCLC harboring KRAS mutations

[Background] Biomarkers like epidermal growth factor receptor (EGFR) gene mutations or anaplastic lymphoma kinase (ALK) rearrangement have been discovered in lung cancer, leading to targeted therapies developed in non-small cell lung cancer (NSCLC). Several oncogenes have been reported to be negative biomarkers for response to tyrosine kinase inhibitors (TKIs), for example, NSCLC with KRAS mutations are resistant to EGFR-TKIs. A preclinical study showed that KRAS mutant lung cancer cells were sensitive to pemetrexed, while a retrospective study reported that pemetrexed-based chemotherapy didn9t show a favorable outcomes in patients with KRAS mutant NSCLC. We, therefore, studied efficacy of pemetrexed-based chemotherapy in patients with NSCLC, and compared the efficacy between KRAS and wild-type NSCLC. [Methods] We retrospectively studied the medical records of patients diagnosed with NSCLC between 2013 to 2015. Genomic DNA (gDNA) was extracted from FFPE tissue samples (QIAamp DNA FFPE Tissue Kit, QIAGEN). KRAS mutations were evaluated using Ion Torrent NGS systems (Ion PGM, Thermo Fischer Scientific) or PCR-rSSO. AmpliSeq Colon and Lung Cancer Research Panel v2 was used in the present study. We used Ion Reporter software for next-generation sequencing data analysis. [Results] We analyzed the data of 226 patients with NSCLC and successfully extracted gDNA from 94 tissue samples. Among them, mutation analysis by Ion PGM system was performed in 48 samples and PCR-rSSO in 46 samples. We will report response rate and progression free survival in the patients treated with pemetrexed-based chemotherapy. Citation Format: Shunsuke Okumura, Takaaki Sasaki, Shin-ichi Chiba, Masatoshi Sado, Naoyuki Miyokawa, Hiroshi Funakoshi, Yoshinobu Ohsaki. Efficacy of pemetrexed-based chemotherapy in patients with NSCLC harboring KRAS mutations. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 2267.

Metachronous pancreatic cancer originating from disseminated founder pancreatic intraductal neoplasias.

330 Background: Clonal populations originated from benign-looking “founder cells” may spread widely within pancreas instead of being localized in situ before frank pancreatic ductal adenocarcinoma (PDA) can be detected. Metachronous PDA is not common event, and we here sought to define potent origin of multiple PDAs developed in a woman by using advanced genetics technologies. Methods: In addition to precise pathological assessment, genetic approaches such as deep sequencing of multiplex PCR amplicons of cancer-associated genes (Ion Torrent PGM platform) and digital PCR were employed. Results: Curative resection of pancreatic head tumor was performed; however, “recurrent” lesions in the remnant pancreas were found 3.5-years later and total pancreatectomy was subsequently performed. The metachronous lesions were morphologically similar to the primary PDA. All 3 PDAs were shown to possess rare somatic mutations in KRAS (p.T58I and p.Q61H). Curiously, identical KRAS mutations were found in low-grade “intraep...