The TGF-ß/Smad2/3 signaling pathway is involved in Musashi2-induced invasion and metastasis of colorectal cancer.

To identify Musashi2 as an effective biomarker regulated by the TGF-ß/Smad2/3 signaling pathway for the precise diagnosis and treatment of colorectal cancer (CRC) through bioinformatic tools and experimental verification. The Cancer Genome Atlas, Timer, and Kaplan-Meier analyses were performed to clarify the expression of Musashi2 and its influence on the prognosis of CRC. Transforming growth factor beta 1 (TGF-ß1) was used to activate the TGF-ß/Smad2/3 signaling pathway to identify whether it could regulate the expression and function of Musashi2. Western blot analysis and quantitative PCR analyses were conducted to verify the expression of Musashi2. Cell counting kit-8 (CCK8), EdU, wound healing, and Transwell assays were conducted to reveal the role of Musashi2 in the proliferation, migration, and invasion of CRC. Musashi2 was upregulated in CRC and promoted proliferation and metastasis. TGF-ß1 increased the expression of Musashi2, while the antagonist inducer of type II TGF-ß receptor degradation-1 (ITD-1) decreased the expression. CCK8 and EdU assays demonstrated that inhibition of Musashi2 or use of ITD-1 lowered proliferation ability. The Transwell and wound healing assays showed that the migration and invasion abilities of CRC cells could be regulated by Musashi2. The above functions could be enhanced by TGF-ß1 by activating the TGF-ß/Smad2/3 signaling pathway and reversed by ITD-1. A positive correlation was found between Musashi2 and the TGF-ß/Smad2/3 signaling pathway. TGF-ß1 activates the TGF-ß/Smad2/3 pathway to stimulate the expression of Musashi2, which promotes the progression of CRC. Musashi2 might become a target gene for the development of new antitumor drugs.

The Hypoxic Landscape Stratifies Gastric Cancer Into 3 Subtypes With Distinct M6a Methylation and Tumor Microenvironment Infiltration Characteristics.

The interaction between hypoxia and RNA N6-methyladenosine (m6A) is an emerging focus of investigation. However, alterations in m6A modifications at distinct hypoxia levels remain uncharacterized in gastric cancer (GC). Unsupervised hierarchical clustering was performed to stratify samples into different clusters. Differentially expressed gene analysis, univariate Cox proportional hazards regression analysis, and hazard ratio calculations were used to establish an m6A score to quantify m6A regulator modification patterns. After using an algorithm integrating Least absolute shrinkage and selection operator (LASSO) and bootstrapping, we identified the best candidate predictive genes. Thence, we established an m6A-related hypoxia pathway gene prognostic signature and built a nomogram to evaluate its predictive ability. The area under the curve (AUC) value of the nomogram was 0.811, which was higher than that of the risk score (AUC=0.695) and stage (AUC=0.779), suggesting a high credibility of the nomogram. Furthermore, the clinical response of anti-PD-1/CTLA-4 immunotherapy between high- and low-risk patients showed a significant difference. Our study successfully explored a brand-new GC pathological classification based on hypoxia pathway genes and the quantification of m6A modification patterns. Comprehensive immune analysis and validation demonstrated that hypoxia clusters were reliable, and our signature could provide a new approach for clinical decision-making and immunotherapeutic strategies for GC patients.

Construction of an N6-methyladenosine lncRNA- and immune cell infiltration-related prognostic model in colorectal cancer.

The present paper aims to shed light on the influence of N6-methyladenosine (m6A) long non-coding RNAs (lncRNAs) and immune cell infiltration on colorectal cancer (CRC). We downloaded workflow-type data and xml-format clinical data on CRC from The Cancer Genome Atlas project. The relationship between lncRNA and m6A was identified by using Perl and R software. Kyoto Encyclopedia of Genes and Genomes enrichment analysis was performed. Lasso regression was utilized to construct a prognostic model. Survival analysis was used to explore the relationship between clusters of m6A lncRNAs and clinical survival data. Differential analysis of the tumor microenvironment and an immune correlation analysis were used to determine immune cell infiltration levels in different clusters and their correlation with clinical prognosis. The expression of lncRNA was tightly associated with m6A. The univariate Cox regression analysis showed that lncRNA was a risk factor for the prognosis. Differential expression analysis demonstrated that m6A lncRNAs were partially highly expressed in tumor tissue. m6A lncRNA-related prognostic model could predict the prognosis of CRC independently. "ECM_RECEPTOR_INTERACTION" was the most significantly enriched gene set. PARP8 was overexpressed in tumor tissue and high-risk cluster. CD4 memory T cells, activated resting NK cells, and memory B cells were highly clustered in the high-risk cluster. All of the scores were higher in the low-risk group. m6A lncRNA is closely related to the occurrence and progression of CRC. The corresponding prognostic model can be utilized to evaluate the prognosis of CRC. m6A lncRNA and related immune cell infiltration in the tumor microenvironment can provide novel therapeutic targets for further research.

N6-Methyladenosine Related Long Non-Coding RNAs and Immune Cell Infiltration in the Tumor Microenvironment of Gastric Cancer.

AIM: To illustrate the influence of N6-methyladenosine long non-coding RNAs and immune cell infiltration in gastric cancer. METHODS: We downloaded workflow-type data and clinical data from The Cancer Genome Atlas project. The relationship of lncRNA and m6A was identified. Kyoto Encyclopedia of Genes and Genomes gene expression enrichment analysis was performed. Lasso regression was utilized to construct a prognostic model. Survival analysis to explore the relationship between m6A lncRNA and clinical survival data. Differential analysis of the tumor microenvironment and immune correlation analysis to determine immune cell infiltration levels and their correlation with clinical prognosis. RESULTS: Co-expression analysis indicated that lncRNA expression was associated closely with m6A. m6A-lncRNAs were partially highly expressed in tumor tissue and could be used in a prognostic model to predict GC prognosis, independent of other clinical characteristics. "ADIPPOCYTOKINE SIGNALING PATHWAY" was most significantly enriched according to GSEA. ACBD3-AS1 was overexpressed in tumor tissue. Naïve B cell, Plasma cells, resting CD4 memory T cell were highly infiltrated tissues in cluster 2, while Macrophages M2, resting Mast cells, Monocytes, regulates T cells were lowly in cluster 1. All related scores were higher in cluster 2, indicating a lower purity of tumor cells and higher density of immune-related cells in the tumor microenvironment. CONCLUSION: m6A lncRNA is closely related to the occurrence and progression of GC. The corresponding prognostic model can be utilized to evaluate the prognosis of GC. m6A lncRNA and related immune cell infiltration in the tumor microenvironment can provide novel therapeutic targets for further research.

Comprehensive analysis of N6-methyladenosine -related long non-coding RNAs and immune cell infiltration in hepatocellular carcinoma.

We aimed to illustrate the influence of N6-methyladenosine (m6A) long non-coding RNAs (lncRNAs) and immune cell infiltration in hepatocellular carcinoma (HCC). The relationship of lncRNAs and m6A was identified through gene expression analysis using PERL and R packages. The Kyoto Encyclopedia of Genes and Genomes gene expression enrichment analysis was performed via gene set enrichment analysis. Lasso regression was utilized to construct prognostic model. Differences in the tumor microenvironment and the immune correlation were analyzed to clarify immune cell infiltration in different clusters and their correlation with the clinical prognosis. Co-expression analysis showed that lncRNA expression was associated closely with m6A. Many lncRNAs were predictive risk factors of prognosis in HCC. m6A-lncRNAs were partially highly expressed in tumor tissue and could be used in a prognostic model to predict HCC prognosis, independent of other clinical characteristics. 'NOTCH SIGNALING PATHWAY' was most significantly enriched according to GSEA. CKLF-like MARVEL transmembrane domain-containing member 3 (CMTM3) was overexpressed in tumor tissue. Immune cells, such as activated CD4 memory T cells, CD8 T cells, and follicular helper T cells, highly infiltrated tissues in cluster 2. All related scores were higher in cluster 2, indicating a lower purity of tumor cells and higher density of immune-related cells in the tumor microenvironment. m6A-lncRNAs are closely related to HCC occurrence and progression. Corresponding prognostic models can help predict HCC prognosis. m6A-lncRNAs and the related immune cell infiltration in the tumor microenvironment can provide novel therapeutic targets in HCC that need to be further studied.[Figure: see text].

Lugol chromoendoscopic screening for esophageal dysplasia/early squamous cell carcinoma in patients with esophageal symptoms in low-risk region in China.

Detection of esophageal dysplasia/early esophageal squamous cell carcinoma (ESCC) is essential for improving 5-year survival. The aim of this prospective study was to evaluate whether Lugol chromoendoscopy improves the detection of esophageal dysplasia/early ESCC in patients with esophageal symptoms in a low-incidence region in China. Eligible patients were randomly assigned into two groups who received routine endoscopy or Lugol chromoendoscopy. During endoscopy, between one and five biopsies were taken from visible lesions for routine endoscopy, or unstained areas of >0.5 cm in diameter for Lugol chromoendoscopy. In total, 812 patients were enrolled, 395 for routine endoscopy and 417 for Lugol chromoendoscopy. The overall detection rate of esophageal dysplasia/early ESCC was 10.6% (86/812), the detection rates were 7.3% (29/395) and 13.7% (57/417) in routine and chromoendoscopy groups, respectively (χ2=8.58, P=0.003). The detection rates were 8.3% (48/580), 17.2% (17/99) and 16.5% (22/133), respectively, in patients with reflux, dysphagia and globus sensation symptoms. In the chromoendoscopy group, 213 patients had unstained lesions of >0.5 cm, the detection rates of dysplasia/early carcinoma were 5.3% (4/76) in those with lesions of 0.5-1.0 cm, and 37.2% (51/137) in those with lesions >1.0 cm (χ2=21.46, P<0.001). These results indicate that Lugol chromoendoscopy improves the detection rate of esophageal dysplasia/early carcinoma in patients with esophageal symptoms compared with routine endoscopy. We propose that Lugol chromoendoscopy must therefore be considered in addition to routine endoscopy in patients with esophageal symptoms.

Chinese National Consensus on diagnosis and management of Barrett's esophagus (BE): revised edition, June 2011, Chongqing, China.

To standardize the diagnosis and management of Barrett's esophagus (BE) in China, the Chinese Society of Gastroenterology convened the Second National Conference on BE in June 2011 in Chongqing, China. After intense discussion among experts in this field and an extensive review of the literature, a revised consensus on the diagnosis and management of BE was generated.

Effects of the inhibition of cyclooxygenase-2 on human esophageal cancer cells: inhibition of cell proliferation and induction of apoptosis.

Cyclooxygenase-2 (COX-2) has been shown to be upregulated in a variety of tumors so that COX-2 may be a potential target in the treatment of cancer. In order to further explore the mechanism, we used RNA interference to study effects of the inhibition of COX-2 on esophageal squamous cell carcinoma (ESCC) lines. Western blot analysis demonstrated that COX-2 expression was significantly reduced in ESCC cells treated with the COX-2-specific siRNA. Furthermore, the COX-2 siRNA treatment inhibited cell proliferation and induced apoptosis in ESCC cells. In addition, the combination treatment of COX-2 siRNA and acidum acetil salicylicum (aspirin) has a synergistic effect. Therefore, this combination has potential as an anticancer therapy for the treatment of ESCC.

Aortoesophageal fistula: a case misdiagnosed as esophageal polyp.

Aortoesophageal fistula (AEF) is a rare and fatal disorder. It is also a life-threatening cause of massive upper gastrointestinal hemorrhage. Thoracic aortic aneurysm is the most common cause of AEF. Management of a patient with this disorder requires rapid diagnosis and immediate intervention, which is considered the best way to save the patient's life. We report a case of AEF misdiagnosed as esophageal polyp.

Clinical and endoscopic features of Chinese reflux esophagitis patients.

AIM: To analyze the clinical and endoscopic features of Chinese patients with reflux esophagitis (RE). METHODS: A total of 1405 RE patients were analyzed retrospectively. Data on gender, age, presence/absence of H pylori infection and associated esophageal hiatal hernia were collected. Esophagitis was divided into different grades according to Los Angeles Classification. RESULTS: Of 18823 patients, 1405 were diagnosed as RE. The ratio of male to female patients was 1.75:1 (P < 0.01). The mean age of male and female patients was significantly different (P = 0.01). The peak age at onset of the disease was 40-60 years. According to Los Angeles Classification, there were significant differences in the age of patients with grades A and B compared to patients with grades C and D (P < 0.01). Two hundred and seventy-seven patients were infected with H pylori, the infection rate was low (P < 0.01). Complication of esophageal hiatal hernia was found to be significantly associated with the severity of esophagitis and age in 195 patients (P < 0.01). Esophageal mucosa damages were mainly located at the right esophageal wall. CONCLUSION: The peak age of onset of RE is 40-60 years and higher in males than in females. The mean age of onset of RE is lower in males than in females. The infection rate of H pylori is significantly decreased in patients with esophagitis. Old age and esophageal hiatal hernia are associated with more severe esophagitis. Right esophageal mucosal damage can occur more often in RE patients.

Aspirin inhibits the proliferation of tobacco-related esophageal squamous carcinomas cell lines through cyclooxygenase 2 pathway.

BACKGROUND: Cigarette smoking has been verified as the risk factor of esophageal squamous cell carcinoma (ESCC). Overexpression of cyclooxygenase 2 (COX-2) is shown in ESCC. The objective of this study was to investigate the effects of cigarette smoking ethanol extract (EE) on the proliferation of the human ESCC cell lines, and to explore the correlation between the proliferation rate of human ESCC cell lines and the expression pattern of COX-2. Whether aspirin can inhibit the proliferation of the ESCC cell lines pretreated with EE, and regulate the mRNA expression levels of COX-2 are also examined. METHODS: Two human ESCC cell lines were selected. EC109 was poorly differentiated and EC9706 was highly differentiated. EC109 and EC9706 were treated with EE and aspirin for different time course. The cell growth of ESCC was measured by MTT reduction assay and the expression of COX-2 was measured by RT-PCR and Western blot analysis. RESULTS: EE promoted the proliferation of EC109 and EC9706 in dose- and time-dependent manners. In the concentration range (10 - 100 microg/ml for EE) and in the time range (24 - 72 hours) after addition of EE, the cell proliferation was prominent in an up-scaled manner respectively. Aspirin could inhibit the proliferation of cell lines EC109 and EC9706, pretreated with EE for 5 hours, in a dose-dependent manner. In the concentration range (0.5 - 8.0 mmol/L for aspirin), the cell growth inhibition was prominent in an up-scaled manner accordingly (P < 0.05). The effect of EE on cell proliferation was correlated with the up-regulation of COX-2 gene. However, the cell growth inhibition of aspirin was correlated with the down-regulation of COX-2 gene. CONCLUSIONS: EE can stimulate the proliferation of human ESCC cell lines EC109 and EC9706, most likely through up-regulating the expression of COX-2. Aspirin can inhibit the proliferation of ESCC cell lines induced by EE, which suggests it may be advantageous in the chemoprevention and therapy of human tobacco-related ESCC. And its effect is likely to be related with modulating COX-2 activity.

[The effect of Helicobacter pylori eradication therapy on bismuth absorption of colloidal bismuth subcitrate].

OBJECTIVE: To investigate whether the acid suppression therapy influences the absorption of bismuth from colloidal bismuth subcitrate (CBS); to locate the deposit position of bismuth in mice's organs and to detect the consequential change of cell functions in these deposited organs. METHODS: 48 male SD rats weighing from 200-250 g were randomly divided into five groups: Group A(1), kill the rats on the cessation day of administration CBS; Group B(1), kill the rats on the day 8 weeks after the cessation of administration CBS; Group A(2) (CBS + amoxicillin + metronidazole + omeprazole), kill the rats on the cessation day of administration; Group B(2) (CBS + amoxicillin + metronidazole + omeprazole), kill the rats on the day 8 weeks after the cessation of administration; Control group. These medicines had been taken every day for 14 days. The issue sections (liver, brain and kidney) were counterstained after AMG development. The bismuth deposited in tissues was observed by microscopy. At the same time, the gray level of kidney tissue sections were measured and compared through image processing program. The deposition of bismuth and the degrees of cell organ's impairment were observed through electron microscopy. By the use of electron probe microanalysis, bismuth can be distinguished from chemical element. RESULTS: The bismuth can be accumulated in cell bodies of proximal convoluted renal tubule, portal area, hypothalamus, and hypoglossal nuclei after its absorption. Under the light microscopy, heavy AMG staining granules were found in cell bodies of proximal convoluted renal tubule. It was discovered that the amounts of bismuth accumulation in kidney of quadruple therapy group were much more than that of single compound therapy group (P < 0.05). The amounts of bismuth accumulation in kidney on the cessation day of administration are more than that 8 weeks later (P < 0.01). What is more, under the electron microscopy, heavy AMG staining granules were found exclusively in lysosomes of proximal convoluted renal tubule cell. The electron microscopy found some cell impairment in quadruple therapy group: the impairment to these cells can be recovered 8 weeks after the cessation of administration. CONCLUSIONS: The acid suppression therapy causes an increase of bismuth absorption and accumulation from CBS in the rats' kidney. Finally, the absorbed bismuth can be discharged out of the body via kidney. Large amounts of bismuth accumulation in kidney can impair the functions of proximal convoluted renal tubule cell.

Characteristics and therapeutic efficacy of sulfasalazine in patients with mildly and moderately active ulcerative colitis.

AIM: To investigate the characteristics and short-term efficacy of sulfasalazine (SASP) in patients with mildly and moderately active ulcerative colitis (UC). METHODS: Two hundred and twenty-eight patients with mildly and moderately active UC were recruited, 106 patients in 1993-1995, and 122 patients in 2000-2002, they were assigned as the 1990s group (n = 106) and the 2000s group (n = 122), prospectively. The general characteristics, clinical manifestations, colonoscopic and histological data were compared between the two groups. The short-term efficacy and safety of SASP 3 g per d were evaluated. RESULTS: Between 2000s and 1990s groups, the gender ratio of men to women was 1:1.18 and 1:1.04, 57.4% and 50.9% of the patients were between 30 and 49 years old. The gender ratio and age of UC patients were not significantly different. The total course of 50.0% and 37.1% of UC patients was less than 1 year (P<0.05), 10.6% and 31.2% of the cases had a duration of more than 5 years (P<0.05) in 2000s and 1990s groups, respectively. The most common clinical type was first episode in 2000s group and chronic relapse in 1990s group. The patients showed a higher frequency of abdominal pain and tenderness in 1990s group than in 2000s group. Erosions were found in 84.4% and 67.9% of patients in 2000s and 1990s groups (P<0.05). Rough and granular mucosa (67.9% vs 43.4%, P<0.05) and polyps (47.2% vs 32.8%, P<0.05) were identified in 1990s group more than in 2000s group. There were no significant differences in clinical, colonoscopic and histological classifications. After SASP (1 g thrice per d) treatment for 6 wk, the clinical, colonoscopic and histological remission rates were 71.8%, 21.8% and 16.4%, respectively. In 79 patients with clinical remission, 58.2% and 67.1% remained grade 1 in colonoscopic and histological findings, respectively. The overall effects in first episode type (complete remission in 10, 18.9%, partial remission in 28, 52.8%, and improvement in 9, 17.0%) were better than in chronic relapse type (complete remission in 3, 7.5%; partial remission in 16, 40.0%; and improvement in 15, 37.5%) and chronic persistent type (complete remission in 1, 5.9%; partial remission in 6, 35.3%; and improvement in 6, 35.3%) respectively (P<0.05). In 110 patients treated with SASP, 18 patients (16.4%) had adverse reactions. Except for two cases of urticaria and one case of WBC decrease, none of the patients had to stop the treatment because of severe adverse reactions. CONCLUSION: Patients with mildly and moderately active UC in 2000s group had a shorter disease course, milder clinical manifestations, more first episode type and higher frequency of acute mucosal lesions in colonoscopy than in 1990s group. The patients in 1990s group had higher proportion of chronic relapse type and chronic mucosal change in colonoscopy than in 2000s group. The short-term efficacy of SASP could be mainly remission of clinical manifestations. But more than half of the patients still had light inflammation in colonoscopy and histology. The overall effects of SASP in first episode type were better than those in other types. SASP was a safe and effective drug to treat mildly and moderately active UC.

[Effect of acid suppression therapy for eradicating Helicobacter pylori infection on bismuth absorption from colloidal bismuth pectin].

OBJECTIVE: To investigate whether acid suppression therapy influences the absorption of bismuth from colloidal bismuth pectin (CBP). METHODS: 48 male SD rats were randomly divided into five groups to be administer with different medicines once a day for 14 days: group A1 (administered with CBP only and killed on the cessation day of administration), group B1 (administered with CBP only and killed 8 weeks after the cessation of administration), group A2 [administered with CBP + amoxicillin (AMO) + metronidazole (MTR) + losec and killed on the cessation day of administration], group B2 (administered with CBP + AMO + MTR + losec and killed 8 weeks after the cessation of administration), and control group (administered with distilled water). The kidney issue sections were counterstained after AMG development. The bismuth deposited in tissues was observed by microscopy. The gray level of kidney tissue sections were measured and compared through image processing program. The deposition of bismuth and the degrees of cell organ's impairment were observed by electron microscopy. By using electron probe microanalysis bismuth was identified from the chemical elements in the specimens. RESULTS: Under the light microscopy, black-brown granules were discovered in the cell bodies of the proximal convoluted renal tubule. The amounts of bismuth accumulated in kidney of the 2 quadruple therapy groups were much more than those of the 2 single compound therapy groups (all P < 0.05). The amount of bismuth accumulated in kidney on the cessation day of administration was more than that eight weeks later (both P < 0.01). Under electron microscopy, black-brown granules were observed exclusively in the lysosomes of the proximal convoluted renal tubule cell. Electron microscopy found cell impairment in the quadruple therapy groups. Impairment of these cells could be recovered 8 weeks after the cessation of administration. CONCLUSION: Acid suppression therapy causes an increase of absorption and accumulation of bismuth from CBP in the kidney. Bismuth can be accumulated in the cell bodies of proximal convoluted renal tubule after its absorption. The absorbed bismuth can be discharged out of the body via kidney. Large amounts of bismuth accumulation in kidney can impair the functions of proximal convoluted renal tubule cells.

A Randomised, Controlled Comparison of Low-Dose Polyethylene Glycol 3350 plus Electrolytes with Ispaghula Husk in the Treatment of Adults with Chronic Functional Constipation.

OBJECTIVE: To compare the efficacy and safety of polyethylene glycol (PEG) 3350 plus electrolytes (PEG+E; Movicol((R))) with that of ispaghula husk (psyllium; Konsyl((R))) in the treatment of constipation. PATIENTS: Male or female adults with chronic functional constipation. METHODS: This was a randomised, controlled, open-label, parallel-group trial. Study treatment was either PEG+E 13.8g/sachet dissolved in water twice daily or ispaghula husk 3.5g/sachet dissolved in water twice daily for a period of 2 weeks. Assessments were at baseline and after 1 and 2 weeks' therapy and by patient daily diary card. The primary outcome measures were weekly defaecation rate, stool consistency according to the Bristol Stool Form scale, time to first defaecation, and overall efficacy, which combined defaecation rate, stool consistency and difficulty on defaecation. Adverse effects were recorded and laboratory assessments were performed before and at the end of the treatment period. RESULTS: Sixty-three patients were randomised to each treatment group. Treatment was highly effective in 50/63 patients in the PEG+E group compared with 26/63 in the ispaghula husk group, and the overall efficacy rates were 92% and 73%, respectively (p = 0.005). PEG+E increased the mean weekly defaecation rate from 1.18 (SD 0.77) at baseline to 7.95 (SD 3.49) after 1 week and 8.48 (SD 3.55) after 2 weeks. In the ispaghula husk group the mean weekly defaecation rate increased from 1.33 (SD 0.68) at baseline to 5.33 (SD 2.81) after 1 week and to 5.71 (SD 2.49) after 2 weeks. The treatment differences for defaecation rates were all statistically significant (p < 0.001). Two weeks of treatment with PEG+E or ispaghula husk normalised stools in 55/63 (87.3%) and 42/63 (66.7%) of patients (p < 0.001). The incidence of adverse effects did not differ between groups and none were serious or required any treatment. Laboratory evaluations found no adverse effect from either treatment. CONCLUSION: The present study demonstrated that low-dose PEG 3350 plus electrolytes is more effective and more rapid in its onset of action than ispaghula husk, and is equally well tolerated.

Differences in endoscopic classification of early colorectal carcinoma between China and Japan: a comparative study.

AIM: To compare the differences in the endoscopic classification of early colorectal carcinoma (CRC) between Japan and China. METHODS: Ten cases of early CRC were included in the study. After reviewing the color pictures of these cases, 5 Japanese endoscopists and 5 Chinese endoscopists made their classificatory diagnosis individually using the current Japanese classification, and indicated their findings on which the diagnosis was based. RESULTS: Some lesions diagnosed by the Japanese endoscopists as IIa or IIa plus IIc, were classified as Is or Isp by the Chinese endoscopists. For superficial lesions consisting of elevation plus central depression, IIa plus depression, IIa plus IIc or IIc plus IIa were classified according to the ratio of elevated area/depressed area. However, international as well as interobserver difference still existed in the classification of such lesions. In addition, most Chinese endoscopists overlooked slightly depressed part on the top of a protruded lesion. Laterally spreading tumor, a special type of IIa, was identified as LST by some Japanese endoscopists. CONCLUSION: Discrepancies on macroscopic classification for early CRC do exist between Japanese and Chinese endoscopists, which are found not only in terminology but also in recognition of some lesions. In order to develop a universal classification, it needs for international communication and cooperation.