Feasibility of Endoscopic Screening for Upper Gastrointestinal Malignancy in a Comprehensive Health Checkup.

Objective In an effort to reduce mortality from gastric cancer, endoscopic screening was introduced in 2016 as a nationwide screening program in Japan. Recent developments in high-definition endoscopic imaging and diagnostic strategies have enabled the simultaneous detection of other upper gastrointestinal (U-GI) malignancies. Therefore, we conducted a study to evaluate the feasibility of endoscopic screening for U-GI malignancy in a comprehensive health checkup. Methods We retrospectively reviewed the data of 13,120 participants who had received a comprehensive health checkup in a single institution between April 2012 and March 2018. Participants were divided into two groups [gastrointestinal endoscopy (GIE) group (n=9,142) and gastrointestinal X-ray (X-ray) group (n=3,978)] and compared with regards to the screening results, adverse events, and detection rate of U-GI malignancies (gastric cancer or other) using a propensity-score matched analysis. Results The gastric cancer detection rate was significantly higher in the GIE group [34/9,142 (0.48%)] than in the X-ray group [3/3,978 (0.08%)] (p=0.003). Other U-GI malignancies were found only in the GIE group and comprised two hypopharyngeal cancers, five esophageal cancers, two duodenal cancers, and one duodenal gastrointestinal stromal tumor. Adverse events occurred in 6/9,142 (0.07%) participants in the GIE group and 18/3,978 (0.45%) participants in the X-ray group (p<0.0001). A propensity-score matched analysis yielded 1,551 matched pairs, and the detection rate of gastric cancer and other U-GI malignancies remained significantly higher in the GIE group than in the X-ray group. Conclusion This study indicated that not only gastric cancer but also other U-GI malignancies can be detected by endoscopic screening.

Feasibility of gastric endoscopic submucosal dissection without using proton pump inhibitor injection: a propensity score analysis.

Purpose: Endoscopic submucosal dissection is a promising method for the resection of superficial gastric neoplasms. To date, several institutions have used proton pump inhibitor injections over the perioperative period. However, there is very little evidence regarding their efficacy. To overcome this limitation, we compared procedural outcomes and the prevention of adverse events of proton pump inhibitor injection with an orally administered active potassium-competitive acid blocker alone. Participants and Methods: We enrolled a total of 150 patients treated for superficial gastric neoplasms at a single institution between April 2015 and December 2018. Patients treated for 2 days with proton pump inhibitor injections following 12 days of oral potassium-competitive acid blocker (proton pump inhibitor group=80) were compared with patients treated for 14 days orally with potassium-competitive acid blocker alone (potassium-competitive acid blocker group=70) using propensity score analysis. We evaluated intragastric pH levels prior to endoscopic submucosal dissection, frequency of intraoperative major bleeding, procedure time, en bloc resection rate, curability, ulcer reduction rate 14 days after endoscopic submucosal dissection, and adverse events (including perforation and postoperative bleeding). Results: Propensity score analysis yielded 43 matched pairs. The comparison demonstrated similar values for the outcomes. For all cases, we observed intragastric pH levels >6.4 prior to endoscopic submucosal dissection. Postoperative bleeding rates were 2.3% (1/43) in the proton pump inhibitor group and 0.0% (0/43) in the potassium-competitive acid blocker group (P=0.315). Conclusions: Oral potassium-competitive acid blocker alone was as effective as proton pump inhibitor injection, with a low incidence of adverse events. Based on these results, proton pump inhibitor injection might be omitted during gastric endoscopic submucosal dissection.

Effect of Continued Administration of Low-dose Aspirin for Intraoperative Bleeding Control in Gastric Endoscopic Submucosal Dissection.

BACKGROUND: The use of antithrombotic agents for the prevention of cerebro-cardioembolic events has increased, and recent guidelines have recommended the continued administration of low-dose aspirin (LDA) during endoscopic procedures with a high risk of bleeding. However, the influence of LDA on intraoperative bleeding control status during Endoscopic submucosal dissection (ESD) remains unclear. METHODS: We examined 293 consecutive patients who underwent ESD for gastric cancers between January 2014 and February 2018. Patients administered with LDA (n = 52) were compared with those without antithrombotic therapy (n = 241; control) by propensity-score matching (PSM) concerning outcomes of ESD. RESULTS: PSM analysis yielded 50 matched pairs. Comparison showed similar values for frequency of intraoperative major bleeding: 1 (0-4) times (median [range]) in the LDA group and 0 (0-5) in the control group respectively (p = 0.710). Others (frequency of preventive coagulation, procedure time, decrease of hemoglobin levels, en bloc resection, complete resection) were the same with a few adverse events including perforation (0%), and thromboembolism (0%). Postoperative bleeding rate was 1.9% in LDA group. Multivariate analysis indicated that location U and circumference on the posterior wall were associated with for multiple major intraoperative bleeding. CONCLUSION: The study suggests that gastric ESD can be safely accomplished without cessation of LDA.

Short-term efficacy of potassium-competitive acid blocker following gastric endoscopic submucosal dissection: a propensity score analysis.

BACKGROUND: Endoscopic submucosal dissection (ESD) is a promising method for the resection of superficial gastric neoplasms. Vonoprazan is a novel potassium-competitive acid blocker (P-CAB) that is currently considered as a potential alternative to proton pump inhibitors (PPIs) for the treatment of acid-related diseases. However, the utility of vonoprazan in ESD-related ulcers is unclear. Therefore, we compared the short-term efficacies of vonoprazan and the PPI lansoprazole in ESD-related ulcer healing during the first two weeks following intervention. METHODS: This study included 115 superficial gastric neoplasms that were treated by ESD at Hiraka General Hospital between April 2015 and January 2017. Patients treated with P-CAB (20 mg vonoprazan, n = 62) or PPI (30 mg lansoprazole, n = 53) were compared using propensity-score matching analysis. Primary outcome was rate of ulcer reduction at two weeks after ESD. Secondary outcomes were coverage ratio of ulcer base by granulation tissue and incidence of postoperative bleeding. RESULTS: The rate of ulcer reduction was significantly higher (median [range], 80.6% [67.6%-94.5%] vs. 62.7% [33.4%-85.2%]; p < .0001) and coverage ratio of the ulcer base by granulation tissue was significantly accelerated (median [range], 84.1% [67.7%-95.3%] vs. 61.9% [12.1%-90.1%]; P < 0.0001) in the P-CAB group compared with the PPI group. Postoperative bleeding was not observed in either group. CONCLUSIONS: P-CAB achieved rapid artificial ulcer healing with promotion of granulation tissue formation. However, conventional PPI with initial intravenous infusion might be sufficient for prevention of postoperative bleeding following gastric ESD.

Feasibility of Knife-Coagulated Cut in Gastric Endoscopic Submucosal Dissection: A Case-Control Study.

BACKGROUND/AIMS: Intraoperative bleeding remains a challenge during endoscopic submucosal dissection (ESD). Forceps-coagulated cut (FCC) was found to be effective to reduce this bleeding. However, this involved frequent device replacement, and therefore, knife-coagulated cut (KCC) might ensure an easier and smoother procedure. We aimed to assess the effectiveness of KCC with Flushknife-BT at a super-low-output setting. METHODS: In this prospective study, we compared the hemostasis condition during ESD in 40 pairs of gastric lesions treated by FCC (Group F) or KCC (Group K). The primary outcome was frequency of major bleeding with an analysis by tumor location. The secondary outcomes included frequency of exchanging devices, procedure time, en bloc resection rate, and adverse event rate. RESULTS: In terms of the frequency of major bleeding, there was no significant difference between Group F and K (0.95 ± 0.12 vs. 0.88 ± 0.17, p = 0.282). Lesions located on the upper third of the stomach involved repeated hemostasis (p = 0.012). The frequency of exchanging devices was higher in Group F than in Group K (6.95 ± 0.42 vs. 0.88 ± 0.17, p = 0.000). Procedure time was reduced in Group K by 15.6%. Other aspects were the same in both groups. CONCLUSION: KCC prevented intraoperative bleeding just as FCC did. But it decreased device replacement and saved time and only a low risk was involved. This technique could ensure the conduct of a smooth and safe procedure during gastric ESD. UMIN000017229.

Proper muscle layer damage affects ulcer healing after gastric endoscopic submucosal dissection.

BACKGROUND AND AIM: Endoscopic submucosal dissection (ESD) is the established therapy for superficial gastrointestinal neoplasms. However, management of the artificial ulcers associated with ESD has become important and the relationship between ulcer healing factors and treatment is still unclear. We aimed to evaluate ESD-related artificial ulcer reduction ratio at 4 weeks to assess factors associating with ulcer healing after ESD that may lead to optimal treatment. METHODS: Between January 2009 and December 2013, a total of 375 lesions fulfilled the expanded criteria for ESD. We defined ulcer reduction rate <90% as (A) poor-healing group; and rate ≥90% as (B) well-healing group. After exclusion, 328 lesions were divided into two groups and analyzed. These two groups were compared based on clinicopathological/endoscopic features, concomitant drugs, and treatment. RESULTS: Ulcer reduction rate was significantly correlated with factors related to the ESD procedure (i.e. procedure time, submucosal fibrosis, and injury of the proper muscle layer, in univariate analysis. Multivariate logistic regression analysis showed that submucosal fibrosis (F2) (P = 0.03; OR, 16.46; 95% CI, 1.31-206.73) and injury of the proper muscle layer (P = 0.01; OR, 4.27; 95% CI, 2.04-8.92) were statistically significant predictors of delayed healing. CONCLUSION: This single-center retrospective study indicated that ESD-induced artificial ulcer healing was affected by submucosal fibrosis and injury of the proper muscle layer, which induced damage to the muscle layer. Therefore, the preferable pharmacotherapy can be determined on completion of the ESD procedure.

Farnesoid X receptor, hepatocyte nuclear factors 1alpha and 3beta are essential for transcriptional activation of the liver-specific organic anion transporter-2 gene.

BACKGROUND: We isolated the human liver-specific organic anion transporter gene, LST-2 (OATP8/SLCO1B3), which is exclusively expressed in the basolateral membrane of the hepatocytes. In this study, we analyzed the transcriptional regulation of the LST-2 gene in hepatocyte-derived cells and the effect of bile acid. METHODS: Transcriptional activity of the LST-2 gene was measured using a human LST-2 promoter-luciferase reporter plasmid under various concentrations of bile acids. Electrophoresis mobility shift assays of farnesoid X receptor (FXR), hepatocyte nuclear factor (HNF) 1alpha, and HNF3beta were performed. RESULTS: Luciferase analysis showed that the 5'-flanking region from -180 to -20 bp is responsible for LST-2 transcriptional activity. By site-directed mutation analysis, it was revealed that the consensus binding sites for FXR, HNF1alpha, and HNF3beta play important roles in the transcriptional activity of the LST-2 gene. By electrophoresis mobility shift assay, we observed specific protein-DNA complexes of FXR, HNF1alpha, and HNF-3beta. Luciferase activity was increased fivefold when chenodeoxycholate or deoxycholate were added. Northern blot analyses revealed that the expression of LST-2 was increased by addition of chenodeoxycholate or deoxycholate in a dose-dependent manner. CONCLUSIONS: This study demonstrated that the transcription of the LST-2 gene is regulated by three transcription factors, FXR, HNF1alpha, and HNF3beta. HNF1alpha and HNF3beta might contribute to its liver-specific expression, and FXR might play a role in its transcriptional activation by bile acids.

Mutations in the serine protease inhibitor Kazal Type 1 (SPINK1) gene in Japanese patients with pancreatitis.

BACKGROUND/AIMS: Recent studies have shown an association between the N34S mutation in the serine protease inhibitor Kazal type 1 (SPINK1) gene and chronic pancreatitis (CP). We here examined the prevalence of SPINK1 mutations in Japanese patients with pancreatitis. METHODS: Genomic DNA was prepared from 80 Japanese patients with CP, 36 patients with acute pancreatitis (AP), and 165 healthy controls. All exons and the promotor region of the SPINK1 gene were amplified by the polymerase chain reaction, and directly sequenced. RESULTS: We found four types of mutation (N34S, IVS1-37T>C, -215G>A, and IVS3 + 2T>C) and two types of polymorphism (-253T>C and 272C>T). The N34S mutation cosegregated with IVS1-37T>C, and was present in 8 CP and 1 AP patients. The -215G>A mutation was in a complete linkage with IVS3 + 2T>C, and was present in 8 CP and 1 AP patients. The prevalences of [N34S; IVS1-37T>C] and [-215G>A; IVS3 + 2T>C] were significantly higher in patients with familial pancreatitis (38 and 13%, respectively) and with idiopathic CP (13 and 16%) than normal subjects (0.6 and 0%). In addition, the frequency of [N34S; IVS1-37T>C] mutation was higher in patients with autoimmune CP (33%). CONCLUSION: The SPINK1 gene mutations were associated with pancreatitis also in Japan.

Hereditary pancreatitis as the premalignant disease: a Japanese case of pancreatic cancer involving the SPINK1 gene mutation N34S.

Mutations in the cationic trypsinogen gene are acknowledged as a risk factor for pancreatic cancer in patients with hereditary pancreatitis. However, whether patients with mutations in other genes, such as the serine protease inhibitor Kazal type 1 (SPINK1) gene, are also at a higher risk of pancreatic cancer remains unknown. We report a case of pancreatic cancer associated with chronic calcifying pancreatitis in a patient with a homozygous N34S mutation in the SPINK1 gene. A 44-year-old woman was hospitalized due to obstructive jaundice. Preoperative examination showed a tumor in the head of the pancreas and multiple pancreatic stones; pancreatoduodenectomy revealed a solid tumor, 3.0 x 2.5 cm in size, in the head of the pancreas, and numerous pancreatic stones throughout the pancreas. Pathologic studies revealed moderately differentiated tubular adenocarcinoma. Mutational analyses of the SPINK1 and PRSS1 genes in members of the patient's family were carried out. The homozygous N34S mutation in the SPINK1 gene was found in the patient and her older sister, who was previously diagnosed with chronic calcific pancreatitis and had undergone the Frey operation. The patient's parents and brother were unaffected carriers of the N34S heterozygous mutation. No family members had any mutations in the cationic trypsinogen gene. To our knowledge, this is the first reported case of chronic pancreatitis accompanied by pancreatic cancer in a patient with the SPINK1 N34S mutation. Although this case does not meet the classic criteria of hereditary pancreatitis, it does suggest that the SPINK1 N34S mutation may be associated with cancer development in patients with hereditary pancreatitis. Further prospective, multicenter trials investigating secondary screening for pancreatic cancer in hereditary pancreatitis are necessary to clarify the role of SPINK1 mutations in the development of pancreatic cancer.

Isolation and characterization of a digoxin transporter and its rat homologue expressed in the kidney.

Digoxin, which is one of the most commonly prescribed drugs for the treatment of heart failure, is mainly eliminated from the circulation by the kidney. P-glycoprotein is well characterized as a digoxin pump at the apical membrane of the nephron. However, little is known about the transport mechanism at the basolateral membrane. We have isolated an organic anion transporter (OATP4C1) from human kidney. Human OATP4C1 is the first member of the organic anion transporting polypeptide (OATP) family expressed in human kidney. The isolated cDNA encodes a polypeptide of 724 aa with 12 transmembrane domains. The genomic organization consists of 13 exons located on chromosome 5q21. Its rat counterpart, Oatp4c1, is also isolated from rat kidney. Human OATP4C1 transports cardiac glycosides (digoxin, K(m) = 7.8 microM and ouabain, K(m) = 0.38 microM), thyroid hormone (triiodothyronine, K(m) = 5.9 microM and thyroxine), cAMP, and methotrexate in a sodium-independent manner. Rat Oatp4c1 also transports digoxin (K(m) = 8.0 microM) and triiodothyronine (K(m) = 1.9 microM). Immunohistochemical analysis reveals that rat Oatp4c1 protein is localized at the basolateral membrane of the proximal tubule cell in the kidney. These data suggest that human OATP4C1/rat Oatp4c1 might be a first step of the transport pathway of digoxin and various compounds into urine in the kidney.

Molecular characterization of human and rat organic anion transporter OATP-D.

We have isolated and characterized a novel human and rat organic anion transporter subtype, OATP-D. The isolated cDNA from human brain encodes a polypeptide of 710 amino acids (Mr 76,534) with 12 predicted transmembrane domains. The rat clone encodes 710 amino acids (Mr 76,821) with 97.6% amino acid sequence homology with human OATP-D. Human and rat OATP-D have moderate amino acid sequence homology with LST-l/rlst-1, the rat oatp family, the prostaglandin transporter, and moatl/MOAT1/KIAA0880/OATP-B. Phylogenetic tree analysis revealed that OATP-D is branched in a different position from all known organic anion transporters. OATP-D transports prostaglandin E1 (Km 48.5 nM), prostaglandin E2 (Km 55.5 nM), and prostaglandin F2,, suggesting that, functionally, OATP-D encodes a protein that has similar characteristics to those of the prostaglandin transporter. Rat OATP-D also transports prostaglandins. The expression pattern of OATP-D mRNA was abundant mainly in the heart, testis, brain, and some cancer cells. Immunohistochemical analysis further revealed that rat OATP-D is widely expressed in the vascular, renal, and reproductive system at the protein level. These results suggest that OATP-D plays an important role in translocating prostaglandins in specialized tissues and cells.

Distribution of rat organic anion transporting polypeptide-E (oatp-E) in the rat eye.

PURPOSE: To examine the protein and mRNA expression levels of the recently cloned rat multifunctional Na+-independent organic anion transporting polypeptide (rat oatp-E), which is involved in the transport of thyroid hormone in the rat, the distribution and function of this transporter were investigated in the retina. METHODS: Real-time quantitative reverse transcription-polymerase chain reaction (RT-PCR) was performed with gene-specific primers for oatp-E in rat ocular tissues. Western blot analysis was performed by raising a specific antibody against oatp-E in rat ocular tissues. Immunohistochemistry was performed with a specific antibody for oatp-E in paraffin sections of rat eyes. The expression of oatp-E in isolated and cultured rat retinal pigment epithelial (RPE) cells was confirmed by RT-PCR, Western blot analysis, and immunohistochemistry. In addition, oatp-E function was analyzed in cultured rat RPE cells by measuring the uptake of triiodothyronine (T3), which is a known substrate for oatp-E. RESULTS: Using real-time quantitative RT-PCR, oatp-E mRNA was detected, in order of highest to lowest concentration, in the rat retina, cornea, and ciliary body-iris. A single band for oatp-E was observed by Western blot analysis in the rat brain, retina, cornea, and ciliary body-iris. oatp-E immunostaining was predominantly expressed in the corneal epithelium, in the pigmented and nonpigmented epithelium of the ciliary body, and in the iris of the rat eye. In the rat retina, intense immunostaining was detected in the RPE, inner and outer nuclear layers, ganglion cell layer, and nerve fiber layer. In addition, oatp-E immunoreactivity in cultured rat RPE cells was expressed in the cell membrane and cytoplasm of RPE cells, a finding that was also confirmed by RT-PCR and Western blot analysis. RPE cells, which were shown to express high levels of oatp-E, transported T3 in a saturable and dose-dependent manner. Moreover, this uptake was significantly inhibited by sulfobromophthalein (BSP), an inhibitor of oatp, suggesting that oatp-E may in part contribute to this uptake. CONCLUSIONS: Results from the present study revealed that rat oatp-E is localized mainly to the corneal epithelium, ciliary body, iris, and retina. Furthermore, the findings appear to suggest that transport of T3 in the RPE may have a functional role for organic anion (i.e., thyroid hormone) transport in the rat eye.

Identification and characterization of novel rat and human gonad-specific organic anion transporters.

We have isolated three novel organic anion transporter cDNAs designated rat GST-1 (gonad-specific transporter), rat GST-2, and human GST, expressed at high levels in the testis. Rat GST-1, GST-2, and human GST consist of 748, 702, and 719 amino acids, respectively, and all molecules possess the 12 predicted transmembrane domains, which is a common structure of organic anion transporters. Northern blot analyses and in situ hybridization revealed that both of the rat molecules are highly expressed in the testis, especially in Sertoli cells, spermatogonia, and Leydig cells. Weak signals are also detected in the epididymis and ovary in adult rat. The exclusive expression of human GST mRNA in the testis was confirmed by RT-PCR. The pharmacological experiments of Xenopus laevis oocytes injected with the respective rat GST-1- and GST-2-cRNAs revealed that both rat GST-1 and GST-2 transport taurocholic acid, dehydroepiandrosterone sulfate, and T4 with Michaelis-Menten kinetics (taurocholic acid, Km = 8.9 and 2.5 microm, dehydroepiandrosterone sulfate, Km = 25.5 and 21.microm, and T4, Km = 6.4 and 5.8 for rat GST-1 and GST-2, respectively). T3 was also transported by rat GST-1 and GST-2. These data suggest that rat GST-1 and GST-2 might be one of the molecular entities responsible for transporting dehydroepiandrosterone sulfate and thyroid hormones involved in the regulation of sex steroid transportation and spermatogenesis in the gonad.