Morihisa Akagi

Genetic Status and Expression of the Cyclin‐dependent Kinase Inhibitors in Human Gastric Carcinoma Cell Lines

Deregulation of cyclin, cyclin‐dependent kinases (CDKs) and their inhibitors could have a pivotal role in the development of diverse human cancers. We examined the genetic status and the expression of CDK inhibitors (p21, p27, pl6 and p15), CDK2 and cyclins (A, D1 and E) in eight gastric carcinoma cell lines, in comparison with the status of p53 gene alterations. All the cell lines (except MKN‐28) that contained a p53 gene abnormality expressed very low or undetectable levels of p21 mRNA, while the cell lines (MKN‐45 and ‐74) with wild‐type p53 gene expressed high levels of p21 mRNA. An inverse correlation was found between the level of p21 mRNA and the expression of mRNAs for CDK2 and G1 cyclins. MKN‐28 was an exception; it contained mutated p53, and expressed mRNAs for p21, CDK2 and G1 cyclins at high levels. Only MKN‐45 and ‐74, with wild‐type p53, expressed considerable levels of p21 protein. Homozygous deletion of the p16 and p15 genes was detected in two (MKN‐45 and HSC‐39) of the eight gastric carcinoma cell lines. p16 protein was not expressed in three cell lines (MKN‐28, MKN‐74 and KATO‐III), as well as MKN‐45 and HSC‐39. Rearrangement of the p15 gene was found in TMK‐1. Rearrangement of the p27 gene was detected in MKN‐45, although the expression of p27 protein was well preserved in all the gastric carcinoma cell lines. The expression of pRb was also preserved in all the cell lines except KATO‐III. No obvious correlation was observed between the p53 gene status and the expression of p27 and p16. These findings suggest that abnormal regulation of CDK2/cyclins and CDK inhibitors might be involved in deregulated growth of gastric carcinomas.

Inhibition of cell growth by transforming growth factor β1 is associated with p53-independent induction of p21 in gastric carcinoma cells

Cell cycle regulators such as cyclins, cyclin‐dependent kinases (cdks) and their inhibitors control the growth of cells. SDI1/CIP1/WAF1/p21 is a potent inhibitor of G1 cdks, whose expression is induced by wild‐type p53. To elucidate the mechanism of growth inhibition by transforming growth factor β1 (TGFβ1), we examined the effect of TGPβ1 on the expression of p21, G1 cyclins and cdks by human gastric cancer cell lines. TGFβ1 induced p21 expression and subsequently suppressed cdk2 kinase activity, followed by a reduction in phosphorylation of the product of the retinoblastoma tumor suppressor gene in TMK‐1 cells, which are responsive to TGFβ1. Coimmunoprecipitation analysis demonstrated that TGFβ1 increased the level of p21 protein present in complexes with cdk2. In contrast, TGFβ1 did not induce p21 in TGFβ1‐resistant MKN‐28 cells. TGFβ1 did not affect the levels of p53 mRNA and protein in TMK‐1 and MKN‐28 cells, which contain mutated p53 genes. These mutated p53 complementary DNAs, when overexpressed, failed to activate transcription from the p21 promoter. Furthermore, TGFβ1 caused a reduction in the steady‐state level of cyclin A protein concomitantly with inhibition of cdk2 kinase activity in TMK‐1 cells. These results suggest that the growth inhibition of tumor cells by TGFβ1 is associated with p53‐independent induction of p21, subsequent suppression of cdk activity and a decrease in cyclin A protein in TMK‐1 cells.

Expression of amphiregulin in human gastric cancer cell lines

Background. Amphiregulin (AR) is a novel gene of the epidermal growth factor (EGF) family. The authors have already reported that AR mRNA was expressed by human gastric carcinoma cells at various degrees, and its expression was induced by the treatment with EGF or transforming growth factor‐alpha (TGF‐α).

Treatment of children and adolescents with ulcerative colitis by adsorptive depletion of myeloid lineage leucocytes as monotherapy or in combination with low dose prednisolone after failure of first-line medications

BackgroundCurrently available drugs for the treatment of ulcerative colitis (UC) include salicylates, thiopurines, corticosteroids and new anti-tumour necrosis factor (TNF)-α biologics. Among these medications, corticosteroids in children and adolescents may adversely affect the patients’ growth and development. Further, UC patients have elevated and activated myeloid lineage leucocytes including the CD14 + CD16+ monocytes, which release TNF-α as a significant exacerbating factor. Accordingly, depletion of these cells by granulocyte/monocyte adsorption (GMA) should alleviate inflammation and promote UC remission. The objective of this study was to evaluate the efficacy of GMA in children and adolescents in whom conventional first-line medications had failed to induce remission.MethodsIn a single centre setting, between 2007 and 2012, a total of 24 consecutive children and adolescents, age 11–19 years were given mesalazine or sulphasalazine as a first-line medication. Seventeen patients relapsed or did not respond to the first-line medications, and received GMA with the Adacolumn, 2 sessions in the first week, and then weekly, up to 11 sessions. Patients who achieved a decrease of ≥5 in the clinical activity index (CAI) were to continue with GMA, while non-responders were to receive 0.5 to 1.0 mg/kg/day prednisolone (PSL) plus additional GMA sessions similar to GMA responder cases. At entry and week 12, patients were clinically and endoscopically evaluated, allowing each patient to serve as her/his own control.ResultsSeven patients achieved remission with the first-line medications and did not receive GMA. Five patients did not respond to the first 5 GMA sessions and received PSL plus GMA, while 12 patients responded to the first 5 GMA sessions and received additional sessions. At entry, the average CAI was 12.7 ± 2.5, range 8–17, and the average endoscopic index was 8.5 ± 1.5, range 7–11. The corresponding values at week 12 were 2.1 ± 0.2, range 1–4 (P < 0.001) and 2.4 ± 0.2, range 1–4 (P < 0.001). PSL was tapered to 0 mg within 3 months.ConclusionsWith the strategy we applied in this study, all 24 consecutive patients achieved remission. In growing patients with active UC refractory to first-line medications, GMA was associated with clinical remission and mucosal healing, while in non-responders to GMA monotherapy, addition of a low dose PSL enhanced the efficacy of GMA and tapering of the PSL dose soon after remission was not associated with UC relapse. Therefore, the majority of young corticosteroid naive UC patients in whom first-line salicylates have failed may respond to GMA and be spared from additional drug therapy. Avoiding corticosteroids at an early stage of UC should ensure better long-term clinical course.

Evaluation of Individual Risk in Nonvariceal Gastrointestinal Bleeding Patients with NSAID Administration: A Multicenter Study in Japan

Backgrounds: Gastrointestinal (GI) toxicity is an undesirable effect of nonsteroidal anti-inflammatory drugs (NSAIDs). We conducted a multicenter study in Japan to clarify the GI risk grade in patients with NSAID-induced GI bleeding. Methods: Patients with emergent endoscopic hemostasis by nonvariceal bleeding were registered from 36 hospitals in Hiroshima. In cases with NSAID use, the GI risk grade (low, moderate, or high) was evaluated, and concomitant drugs were investigated. We asked 79 gastroenterologists and 234 orthopedists what concomitant drugs they would prescribe to 3 simulated patients. Results: A total of 1,350 patients were registered. NSAIDs were used in 278 cases (21%). Concerning the risk grade in each patient, the largest group was the moderate-risk group (203 patients; 73%), while the high-risk group comprised 10% of all NSAID users with bleeding. A proton pump inhibitor (PPI) or misoprostol was administrated to only 20 patients (7%). A small number of the gastroenterologists and orthopedists who responded to the questionnaire would prescribe PPI or misoprostol to simulated patients with short-term loxoprofen use. Conclusions: In NSAID users with GI bleeding, the moderate-risk group was the largest group for GI toxicity in Japan. In these cases, PPI or misoprostol was not commonly medicated in clinical practice.

Sa1585 The Corresponding Rate of Magnification Observation Findings of Narrow Band Imaging (NBI) and Flexible Spectral Imaging Color Enhancement (FICE) in Gastric Tumors and in Colorectal Lesions

The Corresponding Rate of Magnification Observation Findings of Narrow Band Imaging (NBI) and Flexible Spectral Imaging Color Enhancement (FICE) in Gastric Tumors and in Colorectal Lesions Yuko Hiraga*, Masaaki Sumioka, Tomoki Hiramoto, Morihisa Akagi, Daisuke Komichi, Yukio Kuwada, Mikiya Kitamoto, Chiyuki Watanabe, Takashi Nishisaka Department of endoscopy, Hiroshima prefectural Hospital, Hirosima, Japan; Department of gastroenterology, Hiroshima prefectural Hospital, Hirosima, Japan; Department of pathology, Hiroshima prefectural Hospital, Hirosima, Japan Introduction/Objectives: There is a difference in how to see the microvessels by NBI and FICE for the reason that the method of the image enhancement is different, so that it has not been clear whether NBI magnification classification can apply to FICE also. We have been able to use both the instruments in our hospital, so that we were able to do the comparative study of NBI findings and FICE ones at the same lesions for the purpose of examining whether the classification of NBI magnification fits FICE magnification findings also. Methods: We examined a total of 161 lesions (22 gastric tumors, 139 colorectal lesions) that observed by both NBI magnification and FICE magnification between April 2009 and August 2011, treated by endoscopic or surgical resection and diagnosed clinicopathologically. The interval of NBI and FICE examinations was 62.3days (shortest one day, longest 475 days). We examined on the comparison with the NBI findings and the FICE ones and on the relationship between them and histological diagnosis. We classified NBI/FICE magnifying findings according to whether surface pattern was visible or not and whether that was regular or not, and whether microvessels were regular or not and whether avascular area appeared or not. We followed VS classification system (Vascular pattern; regular, irregular or absent, Surface pattern; regular, irregular or absent) in gastric tumors, and followed Hiroshima classification (A, B, C1, C2 or C3) in colorectal lesions. Results: 1) Gastric tumors: In surface pattern diagnosis, FICE findings corresponded with NBI ones at all 22 lesions. But in microvessels pattern diagnosis, evaluations differed in two lesions (regular-irregular, regular-absent). The corresponding rate of NBI and FICE magnification findings was overall 90.9% in gastric tumors, in each of histological diagnosis, it was 91.7% in adenomas, and 90.0% in cancers. 2) Colorectal lesions: The diagnoses of FICE findings differed from NBI ones in 16 lesions, concretely A-B 1 lesion, B-C1 13 lesions and C1-C2 2 lesions. The diagnoses of C3-type, with invisible surface pattern and fragmental microvessels or avascular area, corresponded in all 6 lesions. The corresponding rate of NBI and FICE magnification findings was overall 88.5% in colorectal lesions, in each of histological diagnosis, it was 100% in non-neoplasm, 89.6% in adenomas, 90.5% in intramucosal cancers, and 66.7% in invasive cancers. Conclusions: In gastric tumors and colorectal lesions, the diagnoses between NBI magnification and FICE ones almost corresponded. We were able to apply the classification of NBI magnification to also FICE magnification by using the classification that paid attention to a visibility of surface pattern and to an irregularity of microvessels diameter and distribution.