Effects and risk factors of TAS-102 in real-world patients with metastatic colorectal cancer, EROTAS-R study

BACKGROUND

Trifluridine/tipiracil (TAS-102) is an anticancer drug for metastatic colorectal cancer (CRC). This study aimed to analyze the effects and risk factors about effects of TAS-102 in real-world patients with metastatic CRC (the EROTAS-R study).

METHODS

This study retrospectively analyzed 271 patients aged ≥ 20 years who underwent TAS-102 for metastatic CRC at nine related institutions from 2014 to 2021. Therapeutic results of TAS-102 + bevacizumab (Bev) and TAS-102, effect predictors, adverse events (AE), and AE predictors were examined.

RESULTS

The backgrounds of all cases were as follows: average age, 66.7 ± 10.9 years; male ratio, 59.5%; performance status (PS) 0/1/2, 43.5%/50.6%/5.9%; and tumor site right/left, 25.5%/74.5%. The therapeutic results of 109 cases receiving TAS-102 + Bev and 162 cases receiving TAS-102 were as follows: disease control rate, 53.2% vs. 28.0% (p < 0.01); progressive free survival (PFS), 6.2 vs. 4.2 months (p < 0.01); and overall survival (S), 11.8 vs. 9.3 months (p = 0.03). Multivariate analysis for effect-related factors (odds ratio (OR), 95%confidence interval (CI)) showed the following: PS1 + 2 (0.257, 0.134-0.494, p < 0.01) and a combination of Bev (3.052, 1.598-5.827, p < 0.01). The rates of grade 3 AE for TAS-102 + Bev and TAS-102 were 53.2% and 48.8%, respectively (p = 0.47). Various AE predictors were as follows: male sex (p = 0.69), age ≥ 75 years (p = 0.59), PS1 + 2 (p = 0.20), body surface area < 1.53 m2 (p = 0.26), eGFR < 50 ml/min (p = 0.02), and AST ≥ 50 IU/L (p = 0.64).

CONCLUSION

A better OS and PFS comparing TAS-102 + Bev to TAS-102 for CRC was achieved in a large number of real-world patients.

[A case report:the progress of fascioliasis from hepatic phase to biliary phase]

This is a case report of fascioliasis that progressed from the hepatic to the biliary phases over 2 years. A woman in her late 60s ate Zingiber mioga from the field, which was followed by abdominal pain that occurred 1 month later. Although CT and MRI studies revealed an increase in blood eosinophils as well as multiple hepatic nodules, they vanished quickly. After 2 years, an MRCP study revealed multiple flat lesions, which were diagnosed as adult fascioliasis. Definitive diagnosis was provided by enzyme-labeled antibody method using fasciola-specific antigen. Triclabendazole was administered once to complete the treatment.

Retrospective investigation of mesalamine intolerance in patients with ulcerative colitis

Mesalamine is a key drug in the treatment of ulcerative colitis (UC) for both induction and maintenance therapy. On the other hand, it is known that there are some cases of mesalamine intolerance that are difficult to distinguish from symptoms due to aggravation of UC. The aim of this study is to investigate the clinical characteristic of mesalamine intolerance in UC. A retrospective, observational study was conducted. We enrolled 31 patients who were diagnosed as mesalamine intolerance between April 2015 to March 2020. We examined clinical features, time to onset, drug types of mesalamine, DLST positive rate, colonoscopy findings, disease activity, and clinical course after diagnosis. The average dose of mesalamine was 3.69 g and DLST-positive was 57.1%. Within the first 2 weeks from the start of mesalamine, 51.6% showed symptoms of intolerance. The serum CRP level was relatively high at ≥10.0 mg/dl in 53.6% of the cases. There was no difference in clinical background, symptoms, or laboratory findings between patients with DLST-positive and negative. In this study, we clarified the clinical characteristics of mesalamine intolerant patients, and found no difference in the clinical background or success rate of desensitization therapy between positive and negative DLST cases.

Investigation on the Inhibitory Effect of Wnt-5a on Colonic Mucosal Inflammation in Patients with Ulcerative Colitis

BACKGROUND

Recent progress in ulcerative colitis (UC) treatment has been remarkable, and various medications have been applied. However, some patients with UC are refractory to treatment and convert to surgery.

AIM

To investigate the role of colonic mucosal Wnt-5a expression in the pathogenesis of UC and the effect of bioactive Wnt-5a peptide on colitis in mice.

METHODS

Wnt-5a peptide was intraperitoneally administered to mice every day from the beginning of dextran sulfate sodium (DSS) treatment. The severity of colitis was evaluated based on body weight change, colonic length, and histological scores. Colonic mucosal TNF-α and KC mRNA expression levels were measured. This study included 70 patients with UC in clinical remission. Wnt-5a, TNFα, and IL-8 mRNA expression in the rectal mucosa were measured by quantitative real-time polymerase chain reaction using biopsy materials. Wnt-5a mRNA expression levels were compared between patients who relapsed and those in remission. We examined the correlation of Wnt-5a expression with TNF-α and IL-8 expression.

RESULTS

Wnt-5a peptide significantly attenuated the severity of DSS-induced colitis. Moreover, mucosal TNF-α and KC mRNA expression were significantly suppressed by Wnt-5a peptide treatment. Wnt-5a mRNA levels were significantly lower in patients with subsequent relapse than in those who remained in remission. Mucosal Wnt-5a was inversely correlated with TNF α and IL-8 expression.

CONCLUSION

Wnt-5a peptide suppressed colitis in mice, and decreased Wnt-5a expression was strongly associated with relapse in patients with UC. Wnt-5a may have an inhibitory effect on mucosal inflammation in UC, and Wnt-5a peptide could be a new therapeutic strategy.

Abstract 5953: Modulation of the gut microenvironment by water-soluble dietary fiber alleviates cancer-induced muscle wasting in mice

Cancer cachexia and the associated skeletal muscle wasting are considered poor prognostic factors, although effective treatment has not yet been established. Recent studies have indicated that the pathogenesis of skeletal muscle loss in age-related sarcopenia may involve dysbiosis of the gut microbiota and the accompanying chronic inflammation or altered metabolism, the so-called ‘gut-muscle axis’. However, limited evidence is available on the relationship between cancer-related sarcopenia and the gut environment. Dietary fiber, a non-digestible nutrient including polysaccharides which modulate composition and activity of the gut microbiota, are now noticed for its beneficial effects. In this study, we evaluated the possible effects of modifying the gut microenvironment with partially hydrolyzed guar gum (PHGG), a soluble dietary fiber, on cancer-related muscle wasting and its mechanism using a colon-26 murine cachexia model. Compared to a fiber-free (FF) diet, PHGG contained fiber-rich (FR) diet attenuated body weight and skeletal muscle loss in cachectic mice by suppressing the elevation of the major muscle-specific ubiquitin ligases Atrogin-1 and MuRF1, as well as the autophagy markers LC3 and Bnip3. Although tight junction markers were partially reduced in both FR and FF diet-fed cachectic mice, the abundance of Bifidobacterium, Akkermansia, and unclassified S24-7 family increased by FR diet, contributing to the significant retention of the colonic mucus layer. The reinforcement of the gut barrier function resulted in the controlled entry of pathogens into the host system and reduced circulating levels of lipopolysaccharide-binding protein (LBP) and IL-6, which in turn led to the suppression of proteolysis by downregulating the ubiquitin-proteasome system and autophagy pathway. Moreover, cecal short chain fatty acid (SCFA) levels were relatively low in cachectic mice, although the reduction was mitigated when PHGG supplementation was given. To explore the effects of SCFAs on skeletal muscle mass, we used a well-established in vitro myotube culture model. Exposure of C2C12 myotubes to LPS induced a significant decrease in the diameter, but was reversed on administering a cocktail of SCFAs by suppressing the elevation of Atrogin-1, and upregulating the expression of PGC1α and Tfam, markers of mitochondrial biogenesis. Taken together, our findings suggest that dietary fiber may have the potential to alleviate skeletal muscle loss in cancer cachexia, providing new insights for developing effective strategies in the future.

Citation Format: Tomoki Sakakida, Takeshi Ishikawa, Toshifumi Doi, Ryuichi Morita, Yasuko Hirai, Katsura Mizushima, Yasuki Higashimura, Ken Inoue, Tetsuya Okayama, Kazuhiko Uchiyama, Tomohisa Takagi, Aya Abe, Ryo Inoue, Yoshito Itoh, Yuji Naito. Modulation of the gut microenvironment by water-soluble dietary fiber alleviates cancer-induced muscle wasting in mice [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 5953.

Effect of concomitant use of G-CSF and myelosuppressive chemotherapy on bone marrow and peripheral granulocytes in a mouse model

Granulocyte-colony stimulating factor (G-CSF) stimulates bone marrow progenitor cell proliferation and enhances neutrophil production. Exogenous G-CSF administration is indicated for chemotherapy-induced neutropenia management. However, there is a paucity of basic research examining the effects of the concomitant use of G-CSF and chemotherapy on myeloid cells in vivo. Whether concomitant G-CSF and chemotherapy adversely affect myeloid cell proliferation have not been determined. Herein, we examined the effects of the concomitant use of pegfilgrastim and 5-fluorouracil on myeloid cells and peripheral blood cells in mouse models. Balb/c mice were treated intraperitoneally with 5-fluorouracil (20 μg/g b.w.) or a vehicle as a control for 5 days, and pegfilgrastim was administered subcutaneously at 1 μg/g b.w. on day 3. As a result, we demonstrated that the concomitant use of pegfilgrastim suppressed the 5-fluorouracil-induced decrease of granulocytic cells in both bone marrow and peripheral blood in mice. To assess the clinical efficacy of early administration of pegfilgrastim during docetaxel, cisplatin, and 5-fluorouracil therapy in patients with esophageal cancer, we retrospectively identified 42 consecutive patients treated with this regimen. The incidence of both febrile neutropenia and grade 4 neutropenia was significantly lower in patients who received pegfilgrastim than in those who did not receive it (P = 0.002 and P = 0.002, respectively). These results suggest that the concomitant use of pegfilgrastim and chemotherapy, consisting of continuous infusions of 5-fluorouracil, improved chemotherapy-induced neutropenia without detrimental effects on proliferating myeloid granulocytic cells.

Mucosal interleukin-8 expression as a predictor of subsequent relapse in ulcerative colitis patients with Mayo endoscopic subscore 0

BACKGROUND AND AIM

Complete endoscopic mucosal healing is defined as a Mayo endoscopic subscore of 0. Some patients diagnosed with a Mayo endoscopic subscore 0 may present with subsequent clinical relapse. Here, we aimed to demonstrate mucosal cytokine profile as a predictor of clinical relapse in ulcerative colitis patients with a Mayo endoscopic subscore of 0 as a marker of mucosal healing.

METHODS

We conducted prospective observational pilot study to examine the relationship between mucosal cytokine expression and subsequent relapse of UC patients diagnosed with a Mayo endoscopic subscore of 0. We enrolled 55 patients, and expression of cytokines tumor necrosis factor-α, interferon γ, interleukin-1β, interleukin-2, interleukin-4, interleukin-5, interleukin-6, interleukin-7, interleukin-8, interleukin-9, interleukin-10, interleukin-12, interleukin-13, interleukin-15, interleukin-17A, interleukin-17F, interleukin-18, interleukin-21, interleukin-22, interleukin-23, interleukin-27, and interleukin-33 was measured by quantitative real-time PCR using rectal mucosa biopsy materials. Cytokine expression levels were compared between patients who relapsed between March 1, 2016, and March 30, 2020, of the study period and those who remained in remission.

RESULTS

Ten cytokines, including interleukin-2, interleukin-4, interleukin-8, interleukin-10, interleukin-12, interleukin-15, interleukin-17A, interleukin-21, interleukin-23, and interleukin-33, were significantly elevated in patients with subsequent relapse compared with those who remained in remission. Interleukin-8 expression was the most useful predictor.

CONCLUSIONS

In the rectal mucosa of ulcerative colitis patients with Mayo endoscopic subscore 0, levels of several cytokines were elevated in cases of subsequent relapse. Among these, interleukin-8 expression was the most useful for predicting relapse.

Water-soluble dietary fiber alleviates cancer-induced muscle wasting through changes in gut microenvironment in mice

Cancer cachexia and the associated skeletal muscle wasting are considered poor prognostic factors, although effective treatment has not yet been established. Recent studies have indicated that the pathogenesis of skeletal muscle loss may involve dysbiosis of the gut microbiota and the accompanying chronic inflammation or altered metabolism. In this study, we evaluated the possible effects of modifying the gut microenvironment with partially hydrolyzed guar gum (PHGG), a soluble dietary fiber, on cancer‐related muscle wasting and its mechanism using a colon‐26 murine cachexia model. Compared with a fiber‐free (FF) diet, PHGG contained fiber‐rich (FR) diet–attenuated skeletal muscle loss in cachectic mice by suppressing the elevation of the major muscle‐specific ubiquitin ligases Atrogin‐1 and MuRF1, as well as the autophagy markers LC3 and Bnip3. Although tight‐junction markers were partially reduced in both FR and FF diet–fed cachectic mice, the abundance of Bifidobacterium, Akkermansia, and unclassified S24‐7 family increased by FR diet, contributing to the retention of the colonic mucus layer. The reinforcement of the gut barrier function resulted in the controlled entry of pathogens into the host system and reduced circulating levels of lipopolysaccharide‐binding protein (LBP) and IL‐6, which in turn led to the suppression of proteolysis by downregulating the ubiquitin‐proteasome system and autophagy pathway. These results suggest that dietary fiber may have the potential to alleviate skeletal muscle loss in cancer cachexia, providing new insights for developing effective strategies in the future.

The first case of SMARCA4-deficient sarcoma of stomach

SMARCA4-deficient sarcoma was first reported in the chest and recently in the uterus, but not in the stomach. Here, we present a patient diagnosed with SMARCA4-deficient sarcoma of the stomach, using histochemistry. An emergency operation was performed due to perforation of the tumor. However, one month after the operation, two nodes recurred, and six cycles of combination chemotherapy consisting of adriamycin and ifosfamide were administered. The combination chemotherapy showed a remarkable effect, and complete remission was achieved. The patient was alive without recurrence after 48-month follow-up. SMARCA4-deficient sarcoma is an exceedingly rare tumor with an extremely poor therapeutic response to anticancer drugs. Herein, we present the first case of SMARCA4-deficient sarcoma of the stomach, where a complete response to chemotherapy was achieved.

Treatment with broad-spectrum antibiotics upregulates Sglt1 and induces small intestinal villous hyperplasia in mice

Although extensive evidence indicates that the gut microbiota plays a crucial role in regulating glucose homeostasis, the exact regulatory mechanism remains unclear. This study aimed to investigate the effect of broad-spectrum antibiotics on the expression of glucose transporters, histomorphology of the small intestine, and glucose metabolism in mice. C57BL/6 mice were administered drinking water with or without a broad-spectrum antibiotic combination for 4 weeks. Thereafter, an oral glucose tolerance test was performed. Body weight, small intestine histopathology, mRNA levels of glucose transporters (SGLT1 and GLUT2) and intestinal transcription factors (CDX1 and CDX2) were evaluated. SGLT1 and CDX1 were upregulated in the small intestine upon antibiotic administration compared with that in the control group. The height and surface area of the jejunal villi were significantly higher upon antibiotic administration than in the control group. Fasting glucose levels were significantly higher upon antibiotic administration than in the control group. The present results indicate that treatment with broad-spectrum antibiotics upregulates SGLT1 and CDX1 and induces hyperplasia in the small intestine, thus increasing fasting blood glucose levels. Our results further the current understanding of the effects of broad-spectrum antibiotics on the gut microbiota and glucose homeostasis that may have future clinical implications.

Partially hydrolyzed guar gum attenuates non-alcoholic fatty liver disease in mice through the gut-liver axis

BACKGROUND

The gut-liver axis has attracted much interest in the context of chronic liver disease pathogenesis. Prebiotics such as dietary fibers were shown to attenuate non-alcoholic fatty liver disease (NAFLD) by modulating gut microbiota. Partially hydrolyzed guar gum (PHGG), a water-soluble dietary fiber, has been reported to alleviate the symptoms of various intestinal diseases and metabolic syndromes. However, its effects on NAFLD remain to be fully elucidated.

AIM

To determine whether treatment with PHGG attenuates NAFLD development in mice through the gut-liver axis.

METHODS

Seven-week-old male C57BL/6J mice with increased intestinal permeability were fed a control or atherogenic (Ath) diet (a mouse model of NAFLD) for 8 wk, with or without 5% PHGG. Increased intestinal permeability was induced through chronic intermittent administration of low-dose dextran sulfate sodium. Body weight, liver weight, macroscopic findings in the liver, blood biochemistry [aspartate aminotransferase (AST) and alanine aminotransferase (ALT), total cholesterol, triglyceride, free fatty acids, and glucose levels], liver histology, myeloperoxidase activity in liver tissue, mRNA expression in the liver and intestine, serum endotoxin levels in the portal vein, intestinal permeability, and microbiota and short-chain fatty acid (SCFA) profiles in the cecal samples were investigated.

RESULTS

Mice with increased intestinal permeability subjected to the Ath diet showed significantly increased serum AST and ALT levels, liver fat accumulation, liver inflammatory (tumor necrosis factor-α and monocyte chemotactic protein-1) and fibrogenic (collagen 1a1 and α smooth muscle actin) marker levels, and liver myeloperoxidase activity, which were significantly attenuated by PHGG treatment. Furthermore, the Ath diet combined with increased intestinal permeability resulted in elevated portal endotoxin levels and activated toll-like receptor (TLR) 4 and TLR9 expression, confirming that intestinal permeability was significantly elevated, as observed by evaluating the lumen-to-blood clearance of fluorescein isothiocyanate-conjugated dextran. PHGG treatment did not affect fatty acid metabolism in the liver. However, it decreased lipopolysaccharide signaling through the gut-liver axis. In addition, it significantly increased the abundance of cecal Bacteroides and Clostridium subcluster XIVa. Treatment with PHGG markedly increased the levels of SCFAs, particularly, butyric acid, acetic acid, propionic acid, and formic acid, in the cecal samples.

CONCLUSION

PHGG partially prevented NAFLD development in mice through the gut-liver axis by modulating microbiota and downstream SCFA profiles.

Identification of colorectal neoplasia by using serum bile acid profile

BACKGROUND

Colonoscopy is the gold standard for detecting earlier stages of CRC, although screening of patients is difficult because of invasiveness, low compliance and procedural health risks. Therefore, the need for new screening methods for CRC is rising. Previous studies have demonstrated the diagnostic ability of serum BAs; however, the results have been inconsistent. In this study, we conducted a comprehensive analysis of serum BAs from patients with CRC and verified their diagnostic ability to detect CRC.

METHODS

A total of 56 CRC patients (n = 14 each of stages I-IV), 59 patients with colonic adenoma and 60 healthy controls were included. Age and sex were matched for each group. Serum BA compositions were measured by LC-MS/MS and serum concentration of 30 types of BAs were analysed by discriminant analysis with multidimensional scaling method.

RESULTS

Free CA, 3epi-DCA&CDCA, 3-dehydro CA, GCA and TCA were extracted as principal component (PC) 1 and free 3-dehydroDCA as PC 2 by canonical discriminant function coefficients. The verification of discriminability using cross-validation method revealed that the correct classification rate was 66.3% for original data and 52.6% for cross-validation data.

CONCLUSIONS

A combined analysis using comprehensive serum BA concentration can be an efficient method for screening CRC.

Rectal administration of carbon monoxide inhibits the development of intestinal inflammation and promotes intestinal wound healing via the activation of the Rho-kinase pathway in rats

The inhalation of carbon monoxide (CO) gas and the administration of CO-releasing molecules were shown to inhibit the development of intestinal inflammation in a murine colitis model. However, it remains unclear whether CO promotes intestinal wound healing. Herein, we aimed to evaluate the therapeutic effects of the topical application of CO-saturated saline enemas on intestinal inflammation and elucidate the underlying mechanism. Acute colitis was induced with trinitrobenzene sulfonic acid (TNBS) in male Wistar rats. A CO-saturated solution was prepared via bubbling 50% CO gas into saline and was rectally administrated twice a day after colitis induction; rats were sacrificed 3 or 7 days after induction for the study of the acute or healing phases, respectively. The distal colon was isolated, and ulcerated lesions were measured. In vitro wound healing assays were also employed to determine the mechanism underlying rat intestinal epithelial cell restitution after CO treatment. CO solution rectal administration ameliorated acute TNBS-induced colonic ulceration and accelerated ulcer healing without elevating serum CO levels. The increase in thiobarbituric acid-reactive substances and myeloperoxidase activity after induction of acute TNBS colitis was also significantly inhibited after CO treatment. Moreover, the wound healing assays revealed that the CO-saturated medium enhanced rat intestinal epithelial cell migration via the activation of Rho-kinase. In addition, the activation of Rho-kinase in response to CO treatment was confirmed in the inflamed colonic tissue. Therefore, the rectal administration of a CO-saturated solution protects the intestinal mucosa from inflammation and accelerates colonic ulcer healing through enhanced epithelial cell restitution. CO may thus represent a novel therapeutic agent for the treatment of inflammatory bowel disease.

Higher Levels of Streptococcus in Upper Gastrointestinal Mucosa Associated with Symptoms in Patients with Functional Dyspepsia

BACKGROUND

Functional dyspepsia (FD) is associated with poor health-related quality of life. Recent evidence suggests that the main pathogenesis suspect is the gut mucosa-associated microbiota (MAM). However, little is known about the MAM in FD subjects. The aim of this study was to clarify the relationship between upper gastrointestinal symptoms in FD and the characteristics of the gastrointestinal MAM.

SUMMARY

Five mucosa samples from the upper gut (intraoral, mid-esophagus, gastric body, gastric antrum, and descending portion of the duodenum) were collected with a brush under endoscopic examination from FD and healthy control subjects. MAM profiles of each sample were analyzed by 16S-rRNA -V3-V4 gene sequences. Questionnaire was used to assess gastrointestinal symptoms in FD. Between FD and healthy control subjects, although the comparison of MAM α-diversity showed no significant differences, the structure of MAM (β-diversity) was clearly different. Only the phylum Firmicutes was increased in FD compared to healthy control subjects in all sites of the upper gut. At the genus level, Streptococcus was significantly increased in all sites in the upper gut in FD. The relative abundance of Streptococcus was positively correlated with upper gastrointestinal symptoms in each upper gut group. Furthermore, the relative abundance of OTU 90 was positively correlated with upper gastrointestinal symptoms in all sites in the upper gut in FD. Key Messages: Streptococcus is a bacterium strongly correlated with upper gastrointestinal symptoms in FD.

High-Fat Diet Causes Constipation in Mice via Decreasing Colonic Mucus

BACKGROUND

Constipation is one of the most common gastrointestinal complaints. Although the causes of constipation are varied, dietary habits have a significant influence. Excessive fat intake is suggested as one of the main causes of constipation; however, the exact mechanism is unknown.

AIMS

To investigate whether a high-fat diet (HFD) causes constipation in mice and to clarify the underlying mechanism, focusing on the amount of colonic mucus.

METHODS

Six-week-old male C57BL/6 mice were randomly divided into two groups: mice fed with HFD and those with normal chow diet (NCD). Fecal weight, water content, total gastrointestinal transit time, and colon transit time were measured to determine whether the mice were constipated. The colonic mucus was evaluated by immunostaining and quantified by spectrometry. Malondialdehyde (MDA) was measured using the thiobarbituric acid (TBA) test as a marker for oxidative stress.

RESULTS

Compared to the NCD group, the weight of feces was less in the HFD group. In the functional experiment, the total gastrointestinal transit time and colon transit time were longer in the HFD group. Furthermore, HFD significantly reduced the amount of colonic mucus. In addition, the reduction in colonic mucus caused by surfactant resulted in constipation in the NCD group.

CONCLUSIONS

HFD causes constipation with delayed colon transit time possibly via the reduction in colonic mucus in mice.

High-Risk Comorbidity Influences Prognosis in Early Gastric Cancer after Noncurative Endoscopic Submucosal Dissection: A Retrospective Study

BACKGROUND

There are few studies reporting the clinical outcomes of noncurative endoscopic submucosal dissection (ESD) for early gastric cancer (EGC) from the perspective of patient health condition/status. Thus, the aim of this study was to investigate clinical outcomes of noncurative ESD considering not only curability but also patient factors such as advanced age, comorbidities, and nutritional status.

METHODS

Between April 2007 and March 2012, 95 patients who underwent noncurative ESD for EGC were enrolled in the study. Patients were categorized by treatment after ESD: additional gastrectomy (49 patients) and follow-up (46 patients). Clinical outcomes were evaluated between the 2 groups for overall survival (OS).

RESULTS

The absence of lymphovascular involvement and age ≥80 years were significantly associated with decision-making for observation after noncurative ESD. The OS rates were higher in female patients, patients with better Eastern Cooperative Oncology Group performance status (≤1) or low-risk comorbidity (Charlson Comorbidity Index [CCI ≤ 2]), patients with ulcerative findings, and those who underwent radical gastrectomy. Multivariate Cox proportional hazards analysis indicated that presence of a high-risk comorbidity (CCI ≥ 3) was a significant prognostic factor (hazard ratio: 16.43, p = 0.024) in patients who underwent noncurative ESD for EGC.

CONCLUSION

High-risk comorbidity is the primary prognostic parameter in terms of patient factors after noncurative ESD for EGC. The CCI should be considered as a prognostic factor in patients who underwent noncurative ESD for EGC.

Promotion of wound healing by acetate in murine colonic epithelial cell via c-Jun N-terminal kinase activation

BACKGROUND AND AIM

Mucosal healing is an important clinical goal in patients with inflammatory bowel disease. Recently, short-chain fatty acids (SCFAs) have been reported to have multifaceted effects to host. However, the effects of SCFAs on wound healing in intestinal epithelial cells are unclear. In the present study, we investigated the effects of acetate, one of the major SCFAs, on the wound healing of murine colonic epithelial cells.

METHODS

Young adult mouse colonic epithelial cells were used to determine the effect of acetate using wound healing assay. Mitogen-activated protein kinase and Rho kinase inhibitor were used to elucidate intracellular signal of wound healing treated with acetate. Meanwhile, Rho activation assays were utilized to measure Rho activation levels. To assess in vivo effects, C57B6 mice with dextran sodium sulfate for 7 days were treated with enema administration of acetate for 7 days. Body weight, disease activity index, colon length, and mucosal break ratio in histology were examined.

RESULTS

Acetate enhanced wound healing and fluorescence intensity of actin stress fiber compared with control. These effects were canceled with pretreatment of c-Jun N-terminal kinase (JNK) inhibitor or Rho kinase inhibitor. Furthermore, JNK inhibitor reduced the activation of Rho induced by acetate. In the dextran sodium sulfate-induced colitis model, the mice with enema treatment of acetate significantly exhibited recovery.

CONCLUSIONS

In this study, we demonstrated that acetate promoted murine colonic epithelial cell wound healing via activation of JNK and Rho signaling pathways. These findings suggested that acetate could have applications as a therapeutic agent for patients with intestinal mucosal damage, such as inflammatory bowel disease.

Metformin inhibits TGF‑β1‑induced epithelial‑mesenchymal transition and liver metastasis of pancreatic cancer cells

Epithelial‑mesenchymal transition (EMT) is considered a crucial event in the development of cancer metastasis. Metformin is a drug used in the treatment of type 2 diabetes. Recently, increasing evidence has indicated that metformin possesses anti‑tumor activities. However, the effects of metformin on EMT and metastases in pancreatic cancer remain unknown. Thus, the present study investigated whether metformin inhibits EMT of human pancreatic cancer cell lines. Pancreatic cancer cells were stimulated with transforming growth factor β1 (TGF‑β1), an activator of EMT signaling, with or without metformin. After 48 h, the levels of epithelial and mesenchymal markers were evaluated by western blot analysis, immunocytochemistry and RT‑qPCR. Cancer cell migration was evaluated by an in vitro wound healing assay. The cells stimulated with TGF‑β1 acquired an elongated and fusiform morphology, which was inhibited by metformin. The wound healing assay revealed that metformin significantly suppressed the TGF‑β1‑stimulated migration of pancreatic cancer cells. Following treatment with metformin, E‑cadherin expression (epithelial marker) was upregulated, and the levels of mesenchymal markers were downregulated, which had been increased by TGF‑β1 in these cells. Exposure of the cells to TGF‑β1 activated the Smad2/3 and Akt/mammalian target of rapamycin (mTOR) pathways, and this effect was inhibited by metformin, suggesting that metformin inhibits TGF‑β1‑induced‑EMT through the down‑regulation of the Smad pathway in PANC‑1 cells and the downregulation of the Akt/mTOR pathway in BxPC‑3 cells. In an animal model of surgical orthotopic implantation, metformin inhibited liver metastasis without a significant reduction in the size of the primary pancreatic tumor. On the whole, the findings of the present study suggest that metformin inhibits EMT and cancer metastasis through the Smad or Akt/mTOR pathway.

Early administration of pegfilgrastim for esophageal cancer treated with docetaxel, cisplatin, and fluorouracil: A phase II study

Preoperative or induction chemotherapy with docetaxel, cisplatin, plus 5‐fluorouracil (DCF) is a promising regimen for advanced esophageal cancer. However, the DCF regimen is associated with a high risk of severe neutropenia or febrile neutropenia (FN). However, the current guidelines fail to recommend an optimal dosing schedule of pegfilgrastim along with the DCF regimen to prevent FN. In the present study, we assessed the efficacy and safety of giving pegfilgrastim early on day 3 during DCF therapy for esophageal cancer. In this single‐arm phase II study, patients with squamous cell carcinoma of the esophagus were recruited. They were treated with the DCF therapy on days 1‐5, with pegfilgrastim given on day 3. Primary endpoint was the occurrence of grade 4 neutropenia. Secondary endpoints included the incidence of FN, grade 3 neutropenia, dose delays/reductions, antitumor effect, and safety. Between July 2016 and December 2018, 23 patients were enrolled. The incidence of grade 4 neutropenia was 8.7% (95% confidence interval 1.1%‐28.0%). No patient experienced FN. Of the 19 patients who received two cycles of DCF, one required a dose reduction/treatment delay due to hematological toxicity in the second treatment cycle. No serious adverse events, considered relevant to pegfilgrastim, were observed. This is the first prospective study that showed an efficacious dosing schedule of pegfilgrastim for preventing hematological toxicity during DCF therapy. The results might be generalized to other similar regimens where continuous infusions of 5‐fluorouracil are used.

Clinical and Pathological Challenges in the Diagnosis of Gastric-Type Differentiated Adenocarcinoma in the Stomach: A Study of Endoscopic Submucosal Dissection Cases

BACKGROUND/AIMS

Gastric-type differentiated adenocarcinoma (GDA) of the stomach is a rare variant of gastric cancer that is highly infiltrating and exhibits early metastasis. However, the endoscopic and pathological features of "early-stage" GDA remain unknown. The aim of this study is to characterize early-stage GDA.

METHODS

We retrospectively enrolled 479 differentiated-type early gastric cancer cases who underwent endoscopic submucosal dissection (ESD). GDA cases were selected based on morphology and immunohistochemistry. Clinicopathological data were compared between gastric- and intestinal-type differentiated adenocarcinomas (IDAs).

RESULTS

Thirteen lesions were classified as GDAs. GDAs as well as IDAs showed irregular microvascular and microsurface patterns with clear demarcation line on magnifying endoscopy with narrow band imaging (M-NBI). The rate of pathological misdiagnosis of GDAs in biopsy specimens was higher than that of IDAs (p = 0.016). GDA was significantly associated with positive lymphovascular invasion (p = 0.016). There was one intramucosal lesion with lymphatic invasion in GDA.

CONCLUSIONS

Although M-NBI is useful to detect GDA, the pathological diagnosis of GDAs in biopsy specimens often remains challenging. When suspicious lesions are not diagnosed as GDA, they should be followed up intensively, or diagnostic ESD has to be performed. ESD specimens should be carefully evaluated because of a higher incidence of lymphovascular invasion.

Ginsenoside Rb1 promotes intestinal epithelial wound healing through extracellular signal-regulated kinase and Rho signaling

BACKGROUND AND AIM

Daikenchuto, a traditional Japanese herbal medicine, has been reported to exhibit anti-inflammatory effects against intestinal inflammation. However, whether daikenchuto has a therapeutic effect against intestinal mucosal injuries remains unclear. Thus, the aim of this study was to determine the effect of daikenchuto on intestinal mucosal healing.

METHODS

Colitis was induced in male Wistar rats by using trinitrobenzenesulfonic acid. Daikenchuto (900 mg/kg/day) was administered for 7 days after the induction of colitis. Thereafter, intestinal mucosal injuries were evaluated by determining the colonic epithelial regeneration ratio ([area of epithelial regeneration/area of ulcer] × 100). Restoration of rat intestinal epithelial cells treated with daikenchuto and its constituent herbs (Zanthoxylum fruit, processed ginger, and ginseng) and ginsenoside Rb1, which is a ginseng ingredient, was evaluated using a wound-healing assay.

RESULTS

The colon epithelial regeneration ratio in the daikenchuto-treated rats was significantly higher than that in the control rats. Daikenchuto, ginseng, and ginsenoside Rb1 enhanced wound healing, and the ginsenoside Rb1-induced enhancement was inhibited by extracellular signal-regulated kinase and Rho inhibitors.

CONCLUSIONS

Daikenchuto and its constituent, ginsenoside Rb1, promoted wound healing. Because mucosal healing is one of the most important therapeutic targets in patients with inflammatory bowel disease, ginsenoside Rb1 may be a novel therapeutic agent against intestinal mucosal damage such as that occurring in intestinal bowel disease.

Abstract 1038: Metformin inhibits epithelial-mesenchymal transition in human pancreatic cancer cell lines

Background: Epithelial-mesenchymal transition (EMT) is considered to be a crucial event in the development of cancer metastasis. Metformin is an antidiabetic drug used in treatment of type 2 diabetes. Recently, increasing evidence has indicated that metformin can inhibit tumor growth, however, effect of metformin on EMT remains still well unknown.

Methods: We investigated whether metformin inhibits EMT in the human pancreatic cancer cell lines (PANC-1, BXPC-3, and MIAPaCa-2). Pancreatic cancer cells were stimulated TGF-β1 (10ng/ml) with or without metformin(10mM). After 48h, we evaluated for EMT-related factors using western blot analyses, immunocytochemistry and RT-PCR. Wound healing assay was performed to determine cell migration.

Results: The cells stimulated TGF-β1 acquired elongated and fusiform morphology, and metformin inhibited the TGF-β1-induced morphological changes in PANC-1 and BXPC-3 cells. Wound healing assay of PANC-1 and MIAPaCa-2 cells showed that significant wound healing was seen after 24h in cells treated with TGF-β1 compared with the control, and metformin inhibited wound closure. E-cadherin expression weakened after exposure to TGF-β1, but it was reversed by metformin in these cell lines. Metformin treatment reduced the expression of mesenchymal markers (Vimentin, N-cadherin and αSMA) induced by TGF-β1 in these cell lines. Exposure of cells to TGF-β1 resulted in the phosphorylation of mTOR, and exposure of cells to metformin resulted in the phosphorylation of AMPK and blocked the phosphorylation of mTOR in BXPC-3 cells. Furthermore, cell viability was no significantly change between exposing metformin or not.

Discussion: Our results indicate that metformin inhibits TGF-β1 induced EMT in human pancreatic cancer cells. Moreover, our results suggest that metformin induces the phosphorylation of AMPK and inhibits TGF-β1 induced mTOR activation in BXPC-3 cells.

Citation Format: Juichiro Yoshida, Takeshi Ishikawa, Yuki Endo, Shinya Matsumura, Takayuki Ohta, Katsura Mizushima, Yasuko Hirai, Tetsuya Okayama, Naoyuki Sakamoto, Ken Inoue, Kazuhiro Katada, Kazuhiro Kamada, Kazuhiko Uchiyama, Tomohisa Takagi, Yuji Naito, Yoshito Itoh. Metformin inhibits epithelial-mesenchymal transition in human pancreatic cancer cell lines [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 1038.

[Long-Term Survival of a Patient with Small Cell Esophageal Carcinoma Who Underwent Multidisciplinary Therapy-ACase Report]

The patient was a 69-year-old woman.Upper gastrointestinal endoscopy showed a protruding tumor in the mid-thoracic esophagus, and biopsy revealed small cell carcinoma in November 2012. Four courses of neoadjuvant chemotherapy comprising CDDP and CPT-11 were administered, and radical resection was performed in March 2013.I n March 2014, chest computed tomography revealed the recurrence of mediastinal lymph nodes; thus, we administered chemoradiotherapy comprising 5- FU and CDDP, and the size of the recurrent tumors decreased.However, in February 2015, positron emission tomographycomputed tomography revealed liver metastases.Therefore, we switched to a new chemotherapy regimen containing CDDP and VP-16.Although the treatment was very effective and the liver metastases significantly decreased in size, it was discontinued after 9 courses owing to neurotoxicity.Next, 7 courses of chemotherapy comprising amrubicin, which is administered for treating small cell lung carcinoma, were administered, which suppressed tumor growth for approximately 8 months.However, the tumor then re-grew.Chemotherapy comprising S-1 was administered; however, the tumor gradually progressed.The patient died 51 months after the initial treatment.

Efficacy of the combination use of aprepitant and palonosetron for improving nausea in various moderately emetogenic chemotherapy regimens

BACKGROUND

Nausea is more difficult to control than vomiting in chemotherapy. We therefore analyzed the efficacy of a strong supportive treatment with aprepitant, palonosetron, and dexamethasone against nausea for various moderately emetogenic chemotherapy (MEC).

METHODS

A total of 312 cases treated by palonosetron with or without aprepitant receiving MEC regimens using oxaliplatin, carboplatin, and irinotecan from 2014 to 2016 in our outpatient center for digestive organ cancers, lung cancers, and gynecological cancers were analyzed. Through propensity score matching analysis, cases were divided into 97 cases receiving 2 drugs (palonosetron+dexamethasone) and 97 receiving 3 drugs (aprepitant+palonosetron+dexamethasone). We examined the control rates of nausea for the first two consecutive courses in the both groups. Additionally, risk factors for acute and delayed nausea were analyzed using a multivariate analysis among overall 312 cases.

RESULTS

The control rates of nausea in the two- and the three-drug groups were as follows: acute, 92.8 and 95.9% (p = 0.35); and delayed, 83.5 and 81.4% (p = 0.85), although the control rates of vomiting exceeded 95% in both groups. A multivariate analysis showed that significant risk factors for acute nausea (odds ratio, 95% confidence interval) were elevation of serum creatinine (12.601, 2.437-65.157), general fatigue (3.728, 1.098-12.661), and performance status (PS) 2 (19.829, 3.200-122.865). The significant risk factors for delayed nausea were elevation of alanine aminotransferase (2.397, 1.153-4.984), general fatigue (2.652, 1.380-5.097), and PS 2 (5.748, 1.392-23.740).

CONCLUSIONS

The control for nausea in MEC was insufficient even with palonosetron and aprepitant, and we should pay attention to risk factors for preventing nausea.

Skeletal muscle mass as a predictor of the response to neo-adjuvant chemotherapy in locally advanced esophageal cancer

Undernutrition and sarcopenia are associated with a higher incidence of chemotherapy-related toxicity and a poor prognosis in several kinds of cancer, but the impact of sarcopenia on the outcomes of chemotherapy for esophageal cancer remains unclear. Thus, the purpose of this retrospective study was to investigate whether sarcopenia affects the efficacy and toxicities of chemotherapy for advanced esophageal cancer patients. Data were collected from 31 esophageal cancer patients who underwent neo-adjuvant chemotherapy followed by surgery. Body composition was assessed at the start of chemotherapy by bioelectrical impedance analysis, and outcomes of chemotherapy were compared between sarcopenic and non-sarcopenic groups. Of the 31 patients, sarcopenia was observed in 16 (51.6%). The incidence of toxicities was not different between the two groups. However, as for pathologic response, a good therapeutic effect (Grade 2 or higher) was more common in the non-sarcopenic group than in the sarcopenic group (53.3% vs. 25.0%). Multivariate analysis showed that sarcopenia was an independent predictor of poor pathological response (odds ratio 8.02; P = 0.037). The results of this study suggest the potential utility of sarcopenia assessment in neoadjuvant patient selection strategies.

[Impact of Primary Prophylaxis with Pegfilgrastim on Clinical Outcomes in Patients with Advanced Esophageal Cancer Receiving Chemotherapy with Docetaxel, Cisplatin ,and 5-FU]

It has been reported that docetaxel, cisplatin, and 5-FU combination chemotherapy(DCF)is effective for advanced esophageal cancer. However, we often encounter severe hematotoxicity during DCF therapy. Here, we retrospectively analyzed the data of patients with advanced esophageal cancer treated with DCF at our department, and assessed the efficacy of pegfilgrastim and the issues associated with its use. According to the results, pegfilgrastim may reduce the severe hematotoxicity associated with DCF therapy and may contribute to the maintenance of the intensity of DCF. However, neutropenia had already occurred before pegfilgrastim administration on day 7 in most patients. Therefore, the appropriate timing of pegfilgrastim administration in DCF must be determined in a future prospective study.

Heme oxygenase-1 prevents murine intestinal inflammation

Heme oxygenases (HOs) are rate-limiting enzymes catabolizing heme to biliverdin, ferrous iron, and carbon monoxide, and of the three HO isoforms identified, HO-1 plays a protective role against inflammatory processes. In this study, we investigated the possible role of HO-1 in intestinal inflammation. Acute colitis was induced in male C57BL/6 (wild-type) and homozygous BTB and CNC homolog 1 (Bach1)-deficient mice, which show high HO-1 expression in the colonic mucosa, using dextran sodium sulfate. The disease activity index, myeloperoxidase activity, and inflammatory cytokines in the colonic mucosa were evaluated 7 days after dextran sodium sulfate-dependent colitis induction. We also evaluated the impact of HO-1 inhibition using zinc protoporphyrin IX (25 mg/kg i.p., daily). After dextran sodium sulfate administration, HO-1 mRNA and protein expression increased in a time-dependent manner. Disease activity index score, myeloperoxidase activity, and colonic production of TNF-α and IFN-γ were increased after dextran sodium sulfate administration, and co-administration of zinc protoporphyrin IX enhanced their increase. In addition, disease activity index in Bach1-deficient was significantly lower after dextran sodium sulfate administration than that in wild type mice. These results indicate that HO-1 plays a protective role against dextran sodium sulfate-induced intestinal inflammation, possibly by regulating pro-inflammatory cytokines in intestinal tissues.

Transforming growth factor β1-induced collagen production in myofibroblasts is mediated by reactive oxygen species derived from NADPH oxidase 4

Intestinal fibrosis with stricture formation is a severe complication of Crohn's disease (CD). Though new therapeutic targets to enable the prevention or treatment of intestinal fibrosis are needed, markers of this condition and the basic mechanisms responsible have not been established. NADPH oxidase (NOX) 4 has already been reported to play a key role in models of fibrogenesis, including that of the lung. However, its importance in intestinal fibrogenesis remains unclear. In this study, we examined the role of NOX4 in collagen production by intestinal myofibroblasts stimulated with transforming growth factor (TGF)-β1. Using LmcMF cells, an intestinal subepithelial myofibroblast (ISEMF) line, we first examined the induction of collagen production by TGF-β1. Subsequently, we investigated the role of NOX4 in TGF-β1-induced collagen I production in these cells using SB525334 (an SMAD2/3 inhibitor), diphenyleneiodonium (an NOX inhibitor), and Nox4 small interfering RNA (siRNA). Production of collagen was assessed with Sirius red staining, and Nox4 expression was measured by quantitative real-time PCR. Reactive oxygen species (ROS) production was determined using DCFDA and fluorescent microscopy. We observed that TGF-β1 induced collagen production via NOX4 activation and ROS generation in LmcMF cells. Nox4 siRNA and inhibitors of TGF-β1 receptor and NOX significantly reduced TGF-β1-induced ROS and collagen production. Thus, in the present study, we revealed that collagen production in ISEMFs is induced via an NOX4-dependent pathway. This work supports a function for NOX4 in intestinal fibrogenesis and identifies it as a potential therapeutic target in recalcitrant fibrotic disorders of CD patients.

Impact of the Charlson comorbidity index and prognostic nutritional index on prognosis in patients with early gastric cancer after endoscopic submucosal dissection

BACKGROUND AND AIM

With the aging of society, comorbidities or nutritional status are assessed prior to endoscopic submucosal dissection (ESD) for early gastric cancer (EGC). However, it is uncertain which factors are important for predicting prognosis in EGC patients after ESD. Thus, we aimed to evaluate clinical outcomes of ESD for EGC, with respect to comorbidities or nutritional status.

METHODS

We carried out a retrospective study involving 708 EGC in 585 patients who were enrolled between April 2007 and March 2012. They were classified into two groups; an elderly (≥80 years) and non-elderly (<80 years) group. Short- and long-term outcomes were evaluated between the groups.

RESULTS

There were no significant differences regarding short-term outcomes. Overall survival (OS) rates in the elderly group were significantly lower than those in the non-elderly group (P = 0.001). OS rates in patients with a low (≤2) Charlson comorbidity index (CCI) were significantly higher than those in patients with a high (≥3) CCI, regardless of age. OS rates in patients with a high (≥47.7) prognostic nutritional index (PNI) were significantly higher than those in patients with a low (<47.7) PNI, regardless of age. In multivariate analysis, an Eastern Cooperative Oncology Group performance status (PS) ≥2 (hazard ratio [HR], 95% confidence interval: 3.23, 1.54-6.75), CCI ≥3 (HR 7.88, 4.50-13.80) and PNI <47.7 (HR 3.44, 2.00-5.90) were significantly associated with OS rate (P < 0.01).

CONCLUSION

CCI and PNI can be prognostic indicators for non-elderly and elderly patients with EGC after ESD.

Stenotic Ischemic Enteritis with Concomitant Hepatic Portal Venous Gas and Pneumatosis Cystoides Intestinalis

A 69-year-old man was admitted to a hospital with complaints of abdominal pain. Computed tomography showed hepatic portal venous gas and pneumatosis cystoides intestinalis. Conservative treatment was effective; however, after discharge, he developed complaints of vomiting. Fluoroscopic enteroclysis revealed a stricture in the jejunum necessitating admission to our hospital. Transoral balloon-assisted enteroscopy showed a circumferential ulcer with a stricture. The stricture was surgically resected, and a histopathological examination was consistent with ischemic enteritis. Stenotic ischemic enteritis should be considered among the differential diagnoses in a patient presenting with hepatic portal venous gas and pneumatosis cystoides intestinalis showing small intestinal obstruction.

Heme oxygenase-1 prevents murine intestinal inflammation

Heme oxygenases (HOs) are rate-limiting enzymes catabolizing heme to biliverdin, ferrous iron, and carbon monoxide, and of the three HO isoforms identified, HO-1 plays a protective role against inflammatory processes. In this study, we investigated the possible role of HO-1 in intestinal inflammation. Acute colitis was induced in male C57BL/6 (wild-type) and homozygous BTB and CNC homolog 1 (Bach1)-deficient mice, which show high HO-1 expression in the colonic mucosa, using dextran sodium sulfate. The disease activity index, myeloperoxidase activity, and inflammatory cytokines in the colonic mucosa were evaluated 7 days after dextran sodium sulfate-dependent colitis induction. We also evaluated the impact of HO-1 inhibition using zinc protoporphyrin IX (25 mg/kg i.p., daily). After dextran sodium sulfate administration, HO-1 mRNA and protein expression increased in a time-dependent manner. Disease activity index score, myeloperoxidase activity, and colonic production of TNF-α and IFN-γ were increased after dextran sodium sulfate administration, and co-administration of zinc protoporphyrin IX enhanced their increase. In addition, disease activity index in Bach1-deficient was significantly lower after dextran sodium sulfate administration than that in wild type mice. These results indicate that HO-1 plays a protective role against dextran sodium sulfate-induced intestinal inflammation, possibly by regulating pro-inflammatory cytokines in intestinal tissues.

Abstract 5540: Clinical significance of soluble forms of immune checkpoint molecules in advanced esophageal cancer

Background: Immune checkpoint molecules such as PDL1 and CD155 are expressed on cancer cells and regulate tumor immunity by binding to ligands on immune cells. Although soluble forms of immune checkpoint molecules have been detected in the blood, the roles of these soluble forms have not been fully elucidated. In this study, the clinical significance of soluble forms of immune checkpoint molecules in advanced esophageal cancer was examined. Methods: Soluble PDL1 (sPDL1), PD1(sPD1), CD155(sCD155), and LAG3 (sLAG3) were measured by ELISA in 47 patients who were diagnosed with advanced esophageal cancer and planned to receive multidisciplinary treatment in our department from April 2015 to March 2017. The levels of these molecules in cancer patients were compared with those of 24 control subjects. Results: The mean age of the tumor group was 66 years (41 years to 78 years), the ratio of males and females was 42: 5. Based on TNM-UICC stage grouping, 8, 24 and 15 patients were in clinical stage II, III and IV, respectively. All patients underwent chemotherapy, 25 patients underwent radiation therapy in combination with chemotherapy, and 26 underwent surgical therapy after chemotherapy. There was no difference in age between two groups, but the proportion of male was significantly higher in the cancer group than in the tumor group (P = 0.014). Regarding sPDL1 and sLAG3, there was no significant difference between two groups, but the levels of sPD1 and sCD155 were significantly higher in the tumor group than the control group (sPD1: P = 0.0225; sCD155: P = 0.0006). In subgroup analysis of patients with esophageal cancer, there was a tendency for higher levels of sPD1 in patients with lymph node metastasis (P = 0.150), large tumor diameter (P = 0.189), and higher levels of serum SCC (P = 0.078). The level of sPD1 was related to neither response rate nor overall survival. On the other hand, we did not find any association between clinical characteristics and the level of sCD155. However, the level of sCD155 tended to be higher in patients with response to chemotherapy (CR / PR) (P = 0.111) and in patients with a longer survival (P = 0.183). Discussion: We confirmed that sPD1 and sCD155 are elevated in advanced esophageal cancer. In addition, results in this study suggested that sCD155 may be a biomarker for therapeutic effect or prognostic prediction of esophageal cancer. Large-scale studies are needed to confirm our findings.

Citation Format: Juichiro Yoshida, Takeshi Ishikawa, Takayuki Ohta, Tomoyo Yasuda, Osamu Dohi, Tetsuya Okayama, Naohisa Yoshida, Kazuhiro Kamada, Kazuhiko Uchiyama, Osamu Handa, Tomohisa Takagi, Hideyuki Konishi, Yuji Naitoh, Yoshito Itoh. Clinical significance of soluble forms of immune checkpoint molecules in advanced esophageal cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 5540.

Abstract CT147: Safety and efficacy of high purity and activity NK cells therapy in combination with IgG1 antibody in patients with gastric or colorectal cancer: A phase I clinical trial

Background; Natural killer (NK) cells exhibit strong cytotoxic activity against tumor cells, and produce numerous cytokines resulting in the activation of the adoptive immune systems. Thus, NK cell is considered ideal cell for adoptive cancer immunotherapy. But the difficulty of obtaining large numbers of NK cells that are safe to administer deters its clinical use. We successfully generated large numbers of activated NK cells from small quantities of blood and also determined that the expanded cells were safe to administer in a monotherapy (J Transl Med (2015) 13:277). Since NK cells play a key role in antibody-dependent cellular cytotoxicity (ADCC), administration of NK cells would be expected to enhance the efficacy of IgG1 monoclonal antibodies by augmenting ADCC. This phase I clinical trial evaluated the safety, toxicity, and immunological response of the adoptive NK therapy in combination with IgG1 antibodies.

Patients and Methods; Patients with unresectable advanced gastric or colorectal cancer who have administered or have planned to administer IgG1 antibody (i.e. trastuzumab for HER2 positive gastric cancer or cetuximab for RAS-wild colorectal cancer). NK cells were expanded from PBMCs with the same method in previous clinical trial, briefly ex vivo by stimulating PBMCs with OK432, IL-2, and modified FN-CH296-induced T cells. Expanded NK cells were intravenously injected 3 days after IgG1 antibody administration in a dose-escalating manner (dose 0.5 × 109, 1.0 × 109, 2.0 × 109 cells/injection, three patients/one cohort), every 3 weeks for 3 cycles. We evaluated the safety and efficacy of the combination therapy. To assess the immunological response, immunomonitoring was performed.

Results; Nine eligible patients were enrolled. NK cell populations expanded with our system were confirmed as being enriched in NK cells (median 92.9%) with high expression of NKG2D(97.6%) and CD16(69.6%). This combination therapy was well tolerated with no severe adverse events. Among six evaluable patients, 4 presented SD, 2 presented PD. Of the four SD patients, 3 showed an overall decrease in tumor size after combination therapy. In immunomonitoring analysis, whole blood IFN-gamma production level was increased and the proportion of Treg (Treg/CD4) in peripheral blood was decreased after the combination therapy.

Conclusions; This is the first clinical trial of the combination of adoptive NK cell therapy and IgG1 monoclonal antibodies. Our data provide evidence of good tolerability and preliminary anti-tumor activity for this combination therapy. Moreover, immunological monitoring revealed that the combination therapy induced Th1-type immune response and reduced peripheral Tregs. However, given the limited activity observed in this clinical trial, additional studies are necessary to develop these combination approaches.

Citation Format: Takeshi Ishikawa, Tetsuya Okayama, Naoyuki Sakamoto, Mitsuko Ideno, Kaname Oka, Tatsuji Enoki, Junichi Mineno, Hideyuki Konishi, Satoshi Kokura, Yuji Naito, Yoshito Itoh. Safety and efficacy of high purity and activity NK cells therapy in combination with IgG1 antibody in patients with gastric or colorectal cancer: A phase I clinical trial [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr CT147.

Phase I clinical trial of adoptive transfer of expanded natural killer cells in combination with IgG1 antibody in patients with gastric or colorectal cancer

Natural killer (NK) cells exhibit strong cytotoxic activity against tumor cells without prior sensitization, and have the potential to exert antibody-dependent cellular cytotoxicity (ADCC). In this clinical trial, we examined the safety and efficacy of the use of NK cells, generated using a novel expansion system, in combination with IgG1 antibodies for the treatment of advanced gastric or colorectal cancers. Treatment consisted of trastuzumab- or cetuximab-based chemotherapy, plus adoptive NK cell therapy. For administration of expanded NK cells, dose escalation with a sequential 3 + 3 design was performed in three steps, at doses of 0.5 × 109 , 1.0 × 109 , and 2.0 × 109 cells/injection (N = 9). After 3 days of IgG1 antibody administration, patients were infused with expanded NK cells three times at triweekly intervals. NK cell populations expanded with our system were confirmed as being enriched in NK cells (median 92.9%) with high expression of NKG2D (97.6%) and CD16 (69.6%). The combination therapy was very well tolerated with no severe adverse events. Among six evaluable patients, four presented stable disease (SD) and two presented progressive disease. Of the four SD patients, three showed an overall decrease in tumor size after combination therapy. Immune monitoring suggested that combination therapy enhanced whole blood IFN-γ production and reduced peripheral regulatory T cells (Tregs). In conclusion, this phase I trial provides evidence of good tolerability, induction of Th1 immune responses, and preliminary anti-tumor activity for this combination therapy, in patients with advanced gastric and colorectal cancer that have received previous therapy.

Phase I clinical trial of adoptive transfer of expanded natural killer cells in combination with IgG1 antibody in patients with gastric or colorectal cancer

Natural killer (NK) cells exhibit strong cytotoxic activity against tumor cells without prior sensitization, and have the potential to exert antibody-dependent cellular cytotoxicity (ADCC). In this clinical trial, we examined the safety and efficacy of the use of NK cells, generated using a novel expansion system, in combination with IgG1 antibodies for the treatment of advanced gastric or colorectal cancers. Treatment consisted of trastuzumab- or cetuximab-based chemotherapy, plus adoptive NK cell therapy. For administration of expanded NK cells, dose escalation with a sequential 3 + 3 design was performed in three steps, at doses of 0.5 × 109 , 1.0 × 109 , and 2.0 × 109 cells/injection (N = 9). After 3 days of IgG1 antibody administration, patients were infused with expanded NK cells three times at triweekly intervals. NK cell populations expanded with our system were confirmed as being enriched in NK cells (median 92.9%) with high expression of NKG2D (97.6%) and CD16 (69.6%). The combination therapy was very well tolerated with no severe adverse events. Among six evaluable patients, four presented stable disease (SD) and two presented progressive disease. Of the four SD patients, three showed an overall decrease in tumor size after combination therapy. Immune monitoring suggested that combination therapy enhanced whole blood IFN-γ production and reduced peripheral regulatory T cells (Tregs). In conclusion, this phase I trial provides evidence of good tolerability, induction of Th1 immune responses, and preliminary anti-tumor activity for this combination therapy, in patients with advanced gastric and colorectal cancer that have received previous therapy.

Phase I clinical trial of adoptive transfer of expanded natural killer cells in combination with IgG1 antibody in patients with gastric or colorectal cancer

Natural killer (NK) cells exhibit strong cytotoxic activity against tumor cells without prior sensitization, and have the potential to exert antibody-dependent cellular cytotoxicity (ADCC). In this clinical trial, we examined the safety and efficacy of the use of NK cells, generated using a novel expansion system, in combination with IgG1 antibodies for the treatment of advanced gastric or colorectal cancers. Treatment consisted of trastuzumab- or cetuximab-based chemotherapy, plus adoptive NK cell therapy. For administration of expanded NK cells, dose escalation with a sequential 3 + 3 design was performed in three steps, at doses of 0.5 × 109 , 1.0 × 109 , and 2.0 × 109 cells/injection (N = 9). After 3 days of IgG1 antibody administration, patients were infused with expanded NK cells three times at triweekly intervals. NK cell populations expanded with our system were confirmed as being enriched in NK cells (median 92.9%) with high expression of NKG2D (97.6%) and CD16 (69.6%). The combination therapy was very well tolerated with no severe adverse events. Among six evaluable patients, four presented stable disease (SD) and two presented progressive disease. Of the four SD patients, three showed an overall decrease in tumor size after combination therapy. Immune monitoring suggested that combination therapy enhanced whole blood IFN-γ production and reduced peripheral regulatory T cells (Tregs). In conclusion, this phase I trial provides evidence of good tolerability, induction of Th1 immune responses, and preliminary anti-tumor activity for this combination therapy, in patients with advanced gastric and colorectal cancer that have received previous therapy.

Phase I clinical trial of adoptive transfer of expanded natural killer cells in combination with IgG1 antibody in patients with gastric or colorectal cancer

Natural killer (NK) cells exhibit strong cytotoxic activity against tumor cells without prior sensitization, and have the potential to exert antibody-dependent cellular cytotoxicity (ADCC). In this clinical trial, we examined the safety and efficacy of the use of NK cells, generated using a novel expansion system, in combination with IgG1 antibodies for the treatment of advanced gastric or colorectal cancers. Treatment consisted of trastuzumab- or cetuximab-based chemotherapy, plus adoptive NK cell therapy. For administration of expanded NK cells, dose escalation with a sequential 3 + 3 design was performed in three steps, at doses of 0.5 × 109 , 1.0 × 109 , and 2.0 × 109 cells/injection (N = 9). After 3 days of IgG1 antibody administration, patients were infused with expanded NK cells three times at triweekly intervals. NK cell populations expanded with our system were confirmed as being enriched in NK cells (median 92.9%) with high expression of NKG2D (97.6%) and CD16 (69.6%). The combination therapy was very well tolerated with no severe adverse events. Among six evaluable patients, four presented stable disease (SD) and two presented progressive disease. Of the four SD patients, three showed an overall decrease in tumor size after combination therapy. Immune monitoring suggested that combination therapy enhanced whole blood IFN-γ production and reduced peripheral regulatory T cells (Tregs). In conclusion, this phase I trial provides evidence of good tolerability, induction of Th1 immune responses, and preliminary anti-tumor activity for this combination therapy, in patients with advanced gastric and colorectal cancer that have received previous therapy.

Phase I clinical trial of adoptive transfer of expanded natural killer cells in combination with IgG1 antibody in patients with gastric or colorectal cancer

Natural killer (NK) cells exhibit strong cytotoxic activity against tumor cells without prior sensitization, and have the potential to exert antibody-dependent cellular cytotoxicity (ADCC). In this clinical trial, we examined the safety and efficacy of the use of NK cells, generated using a novel expansion system, in combination with IgG1 antibodies for the treatment of advanced gastric or colorectal cancers. Treatment consisted of trastuzumab- or cetuximab-based chemotherapy, plus adoptive NK cell therapy. For administration of expanded NK cells, dose escalation with a sequential 3 + 3 design was performed in three steps, at doses of 0.5 × 109 , 1.0 × 109 , and 2.0 × 109 cells/injection (N = 9). After 3 days of IgG1 antibody administration, patients were infused with expanded NK cells three times at triweekly intervals. NK cell populations expanded with our system were confirmed as being enriched in NK cells (median 92.9%) with high expression of NKG2D (97.6%) and CD16 (69.6%). The combination therapy was very well tolerated with no severe adverse events. Among six evaluable patients, four presented stable disease (SD) and two presented progressive disease. Of the four SD patients, three showed an overall decrease in tumor size after combination therapy. Immune monitoring suggested that combination therapy enhanced whole blood IFN-γ production and reduced peripheral regulatory T cells (Tregs). In conclusion, this phase I trial provides evidence of good tolerability, induction of Th1 immune responses, and preliminary anti-tumor activity for this combination therapy, in patients with advanced gastric and colorectal cancer that have received previous therapy.

Phase I clinical trial of adoptive transfer of expanded natural killer cells in combination with IgG1 antibody in patients with gastric or colorectal cancer

Natural killer (NK) cells exhibit strong cytotoxic activity against tumor cells without prior sensitization, and have the potential to exert antibody-dependent cellular cytotoxicity (ADCC). In this clinical trial, we examined the safety and efficacy of the use of NK cells, generated using a novel expansion system, in combination with IgG1 antibodies for the treatment of advanced gastric or colorectal cancers. Treatment consisted of trastuzumab- or cetuximab-based chemotherapy, plus adoptive NK cell therapy. For administration of expanded NK cells, dose escalation with a sequential 3 + 3 design was performed in three steps, at doses of 0.5 × 109 , 1.0 × 109 , and 2.0 × 109 cells/injection (N = 9). After 3 days of IgG1 antibody administration, patients were infused with expanded NK cells three times at triweekly intervals. NK cell populations expanded with our system were confirmed as being enriched in NK cells (median 92.9%) with high expression of NKG2D (97.6%) and CD16 (69.6%). The combination therapy was very well tolerated with no severe adverse events. Among six evaluable patients, four presented stable disease (SD) and two presented progressive disease. Of the four SD patients, three showed an overall decrease in tumor size after combination therapy. Immune monitoring suggested that combination therapy enhanced whole blood IFN-γ production and reduced peripheral regulatory T cells (Tregs). In conclusion, this phase I trial provides evidence of good tolerability, induction of Th1 immune responses, and preliminary anti-tumor activity for this combination therapy, in patients with advanced gastric and colorectal cancer that have received previous therapy.

Phase I clinical trial of adoptive transfer of expanded natural killer cells in combination with IgG1 antibody in patients with gastric or colorectal cancer

Natural killer (NK) cells exhibit strong cytotoxic activity against tumor cells without prior sensitization, and have the potential to exert antibody-dependent cellular cytotoxicity (ADCC). In this clinical trial, we examined the safety and efficacy of the use of NK cells, generated using a novel expansion system, in combination with IgG1 antibodies for the treatment of advanced gastric or colorectal cancers. Treatment consisted of trastuzumab- or cetuximab-based chemotherapy, plus adoptive NK cell therapy. For administration of expanded NK cells, dose escalation with a sequential 3 + 3 design was performed in three steps, at doses of 0.5 × 109 , 1.0 × 109 , and 2.0 × 109 cells/injection (N = 9). After 3 days of IgG1 antibody administration, patients were infused with expanded NK cells three times at triweekly intervals. NK cell populations expanded with our system were confirmed as being enriched in NK cells (median 92.9%) with high expression of NKG2D (97.6%) and CD16 (69.6%). The combination therapy was very well tolerated with no severe adverse events. Among six evaluable patients, four presented stable disease (SD) and two presented progressive disease. Of the four SD patients, three showed an overall decrease in tumor size after combination therapy. Immune monitoring suggested that combination therapy enhanced whole blood IFN-γ production and reduced peripheral regulatory T cells (Tregs). In conclusion, this phase I trial provides evidence of good tolerability, induction of Th1 immune responses, and preliminary anti-tumor activity for this combination therapy, in patients with advanced gastric and colorectal cancer that have received previous therapy.

Secreted protein acidic and rich in cysteine functions in colitis via IL17A regulation in mucosal CD4+ T cells

BACKGROUND AND AIM

Secreted protein acidic and rich in cysteine (SPARC) is a matricellular glycol that regulates cell proliferation, tissue repair, and tumorigenesis. Despite evidence linking SPARC to inflammation, the mechanisms are unclear. Accordingly, the role of SPARC in intestinal inflammation was investigated.

METHODS

Colitis was induced in wild-type (WT) and SPARC knockout (KO) mice using trinitrobenzene sulfonic acid (TNBS). Colons were assessed for damage; leukocyte infiltration; Tnf, Ifng, Il17a, and Il10 mRNA expression; and histology. Cytokine profiling of colonic lamina propria mononuclear cells (LPMCs) was performed by flow cytometry. Naïve CD4⁺ T cells were isolated from WT and SPARC KO mouse spleens, and the effect of SPARC on Th17 cell differentiation was examined. Recombination activating gene 1 knockout (RAG1 KO) mice reconstituted with T cells from either WT or SPARC KO mice were investigated.

RESULTS

Trinitrobenzene sulfonic acid exposure significantly reduced bodyweight and increased mucosal inflammation, leukocyte infiltration, and Il17a mRNA expression in WT relative to SPARC KO mice. The percentage of IL17A-producing CD4⁺ T cells among LPMCs from KO mice was lower than that in WT mice when both groups were exposed to TNBS. Th17 cell differentiation was suppressed in cells from SPARC KO mice. In the T cell transfer colitis model, RAG1 KO mice receiving T cells from WT mice were more severely affected than those reconstituted with cells from SPARC KO mice.

CONCLUSIONS

Secreted protein acidic and rich in cysteine accelerates colonic mucosal inflammation via modulation of IL17A-producing CD4⁺ T cells. SPARC is a potential therapeutic target for conditions involving intestinal inflammation.

Early-Stage Gastric Cancer Can Be Found in Improved Atrophic Mucosa over Time from Successful Helicobacter pylori Eradication

BACKGROUND/AIMS

Early-stage gastric cancer (EGC) is detected even after successful Helicobacter pylori eradication. This study is aimed at clarifying the clinicopathological characteristics of EGC detected after successful H. pylori eradication.

METHODS

This retrospective study analyzed 57 cases of EGC detected after successful H. pylori eradication and resected endoscopically at Kyoto Prefectural University of Medicine, between January 2009 and June 2014. Clinicopathological findings of 57 cases (H. pylori-eradicated group) were investigated, and compared with those in active H. pylori infection resected in the same period (H. pylori-positive group).

RESULTS

Most EGCs were detected in patients with severe atrophic mucosa, both in H. pylori-eradicated and H. pylori-positive groups, while the percentage of EGC detected in patients with mild atrophic mucosa gradually increased over time from successful eradication (H. pylori-positive: 7%, up to the fourth year since eradication: 11%, after the fifth year since eradication: 32%). The percentage of EGC detected in patients with mild atrophic mucosa after the fifth year since eradication was significantly higher than that in patients with active H. pylori infection (p = 0.004).

CONCLUSION

After the fifth year following eradication, we should be alert to the incidence of EGC, irrespective of the severity of mucosal atrophic change.

Partially hydrolyzed guar gum enhances colonic epithelial wound healing via activation of RhoA and ERK1/2

BACKGROUND AND AIMS

Healing of the intestinal mucosal epithelium was found to be a critical factor in the treatment of inflammatory bowel disease (IBD). In this study, we provide further evidence that partially hydrolyzed dietary fiber (PHGG) enhances colonic epithelial cell wound healing, and partially characterize the mechanism that governs this process.

MATERIALS AND METHODS

Young adult mouse colonic (YAMC) epithelial cells were scraped with a 10 μl micro-pipette tip to denude a round of the monolayer and were incubated with PHGG. The area of cell migration was measured using Image J software. Meanwhile, Rho activation assays were utilized to monitor Rho activation levels. To assess in vivo effects, C57B6 mice were treated with DSS for 7 days and then provided food supplemented with PHGG for 8 days.

RESULTS

YAMC cells treated with PHGG exhibited significantly enhanced wound healing compared to the control cells; however, this enhancement was inhibited by both Y-27632 (RhoA inhibitor) and U0126 (ERK1/2 inhibitor). Likewise, there was a PHGG-dependent increase in F-actin accumulation and Rho kinase activity that was blocked by U0126. Meanwhile, PHGG-dependent ERK1/2 activity was not inhibited by Y-27632. In the DSS-induced mouse colitis model, animals that received food supplemented with PHGG exhibited significant recovery of the colonic mucosa.

CONCLUSIONS

In this study, we demonstrate that PHGG promotes colonic epithelial cell wound healing via activation of RhoA, which occurs downstream of ERK1/2 activation. These findings indicate that PHGG could be utilized as a therapeutic agent for patients with intestinal mucosal damage such as those with IBD.

Phase I clinical trial of adoptive transfer of expanded natural killer cells in combination with IgG1 antibody in patients with gastric or colorectal cancer

Natural killer (NK) cells exhibit strong cytotoxic activity against tumor cells without prior sensitization, and have the potential to exert antibody-dependent cellular cytotoxicity (ADCC). In this clinical trial, we examined the safety and efficacy of the use of NK cells, generated using a novel expansion system, in combination with IgG1 antibodies for the treatment of advanced gastric or colorectal cancers. Treatment consisted of trastuzumab- or cetuximab-based chemotherapy, plus adoptive NK cell therapy. For administration of expanded NK cells, dose escalation with a sequential 3 + 3 design was performed in three steps, at doses of 0.5 × 10⁹ , 1.0 × 10⁹ , and 2.0 × 10⁹ cells/injection (N = 9). After 3 days of IgG1 antibody administration, patients were infused with expanded NK cells three times at triweekly intervals. NK cell populations expanded with our system were confirmed as being enriched in NK cells (median 92.9%) with high expression of NKG2D (97.6%) and CD16 (69.6%). The combination therapy was very well tolerated with no severe adverse events. Among six evaluable patients, four presented stable disease (SD) and two presented progressive disease. Of the four SD patients, three showed an overall decrease in tumor size after combination therapy. Immune monitoring suggested that combination therapy enhanced whole blood IFN-γ production and reduced peripheral regulatory T cells (Tregs). In conclusion, this phase I trial provides evidence of good tolerability, induction of Th1 immune responses, and preliminary anti-tumor activity for this combination therapy, in patients with advanced gastric and colorectal cancer that have received previous therapy.

The influence of long-term use of proton pump inhibitors on the gut microbiota: an age-sex-matched case-control study

Proton pump inhibitors (PPIs) are widely used to treat gastro-esophageal reflux and prevent gastric ulcers, and have been considered as low risk. However, recent studies have identified possible associations between PPI use and gut microbiota, suggesting that PPIs use increases the risk of enteric infections, including Clostridium difficile infection. To investigate gut microbiota in Japanese PPIs users, we conducted 16S metagenomics analysis of fecal samples collected from PPI users and healthy adults. In total, 36 PPI users and 36 PPI non-users (as control subjects) matched by age and sex were recruited and fecal samples were obtained to analyze the gut microbiome using 16S rRNA gene sequencing. There were significant differences in the microbial structure between PPI non-users and PPI users. In contrast, the analysis of α-diversity revealed no significant differences between PPI non-users and PPI users. When comparing in genus level between these two groups, the genera Streptococcus was significantly abundant and the genera Faecalibacterium was significantly decreased in PPI users. Our findings indicate a probable association between PPI use and the alternation of microbiota. These alterations might provide a mechanism by which PPIs predispose enteric infection such as Clostridium difficile infection.

Correction: A novel lens cleaner to prevent water drop adhesions during colonoscopy and esophagogastroduodenoscopy

[This corrects the article DOI: 10.1055/s-0043-120659.].

A novel lens cleaner to prevent water drop adhesions during colonoscopy and esophagogastroduodenoscopy

BACKGROUND AND STUDY AIMS

 Water drop adhesions (WDA) impair endoscopic view during gastrointestinal endoscopy. We developed a novel lens cleaner designed using two types of harmLess surfactants and it is reported to be useful for preventing lens cloudiness during colorectal ESD. In the current study, we examined the ability of it for preventing and removing WDA.

PATIENTS AND METHODS

 During laboratory experiments, the cleaner (Cleash; Fujifilm Co., Tokyo, Japan and Nagase Medicals Co., Hyogo, Japan) was applied to the endoscopic lens and an air/water device (AWD) (water 200 mL, dimethicone 1 mL, Cleash 1 mL). The endoscope was submerged in water 100 times for 5 cycles. Rates of WDA were calculated for various groups (lens and AWD with or without Cleash) and compared to a normal cleaner (SL cleaner). During clinical research, 30 colonoscopies and 30 esophagogastroduodenoscopies were analyzed. For the Cleash group, the cleaner was applied to both lens and AWD. The numbers of WDA and WDA with non-rapid removal were calculated, compared to those of the SL cleaner group.

RESULTS

 The mean WDA rate for the Cleash setting (lens: Cleash; AWD: Cleash) was 11.0 %, which was significantly lower than other settings (lens: SL cleaner; AWD: water, 31.0 %; P  < 0.001) (lens: Cleash; AWD: water, 19.0 %; P  < 0.001). Clinical research of colonoscopies indicated that the numbers of WDA (number/15 sec) and WDA with non-rapid removal were 0.38 and 0.17 for the Cleash group and 0.91 and 0.46 for the SL cleaner groups ( P  < 0.001, P  < 0.001). For esophagogastroduodenoscopies, the results were 0.47 and 0.24 for the Cleash group and 0.54 and 0.42 for the SL cleaner group ( P  = 0.72, P  = 0.018).

CONCLUSION

 A clear and beautiful image without WDA is useful not only for routine endoscopy but also, more importantly, for magnifying endoscopy and other endoscopic treatments. The use of Cleash to lens and AWD showed positive results for preventing and removing WDA during laboratory experiments and clinical research involving CS. Additionally, it also showed positive results for the removal of WDA during EGD.

Rebamipide upregulates mucin secretion of intestinal goblet cells via Akt phosphorylation

Mucin is produced and secreted by epithelial goblet cells and is a key component of the innate immune system, acting as a barrier in the intestinal tract. However, no studies have been conducted investigating the increase in mucin secretion to enhance the intestinal barrier function. The present study investigated whether rebamipide (Reb) acts as a secretagogue of intestinal mucin and the underlying mechanisms involved, thereby focusing on the effect on goblet cells. The LS174T cell line was used as goblet cell‑like cells. Using Reb‑treated LS174T cells, the level of mucin content was assessed by periodic acid‑Schiff (PAS) staining, and mucin 2, oligomeric mucus/gel‑forming (MUC2) mRNA expression was assessed using quantitative polymerase chain reaction (PCR). Furthermore, MUC2 secretion in the supernatant was quantified by the dot blot method. The present study additionally investigated the involvement of the epidermal growth factor receptor/Akt serine/threonine kinase 1 (Akt) pathway in mucin secretion by western blotting. The results suggested that Reb strongly enhanced the positivity of PAS staining in LS174T cells, thereby suggesting increased intracellular mucin production. The PCR results indicated that Reb significantly increased MUC2 mRNA in whole cell lysate of LS174T cells. In order to assess the subsequent secretion of mucin by LS174T, MUC2 protein expression in the supernatant was assessed using the dot blot method and it was demonstrated that Reb significantly increased the secretion of MUC2 in a concentration‑dependent manner. The p‑Akt was significantly increased by Reb treatment, and an Akt inhibitor specifically suppressed MUC2 secretion. Overall, Reb increased mucin secretion directly via p‑Akt. Reb‑increased mucin may act as a strong non‑specific barrier against pathogenic stimulants in various intestinal diseases.