TET2 Is Downregulated in Early Esophageal Squamous Cell Carcinoma and Promotes Esophageal Squamous Cell Malignant Behaviors.

OBJECTIVE: To explore the expression of the ten eleven translocation (TET) 2 protein in early esophageal squamous cell carcinoma (EESCC), precancerous lesions, and cell lines and to evaluate the effect of TET2 on the functional behavior of EC109 esophageal cancer cells. METHODS: Thirty-one samples of EESCC and precancerous lesions collected via endoscopic submucosal dissection at Taihe Hospital, Shiyan, from February 1, 2017, to February 1, 2019, were analyzed. The study involved evaluating TET2 expression levels in lesion tissue and adjacent normal epithelium, correlating these with clinical pathological features. Techniques including 3-(4,5-dimethythiazol-2-yl)-2,5-diphenyl tetrazolium bromide, cell scratch assays, flow cytometry for propidium iodide (PI) staining, Hoechst 333258/PI double staining, and nude mouse tumorigenesis experiments were employed to assess the effect of TET2 on the proliferation, migration, cell cycle, apoptosis, and tumorigenic ability of esophageal cancer cells. RESULTS: TET2 expression was notably reduced in early esophageal cancer tissue and correlated with tumor invasion depth (P < 0.05). Overexpression of TET2 enhanced the proliferation and migration of esophageal cancer cells, increased the cell population in the G0 phase, decreased it in the S phase, and intensified cell necrosis (P < 0.05). There was a partial increase in tumorigenic ability (P = 0.087). CONCLUSION: TET2 downregulation in ESCC potentially influences the necrosis, cell cycle, and tumorigenic ability of esophageal cancer cells, suggesting a role in the onset and progression of esophageal cancer.

Efficacy of keverprazan for duodenal ulcer: A phase II randomized, double-blind, parallel-controlled trial.

BACKGROUND AND AIM: Considering the limitation of varying acid suppression of proton pump inhibitors, this study was aimed to assess the efficacy, safety, and dose-effect relationship of keverprazan, a novel potassium-competitive acid blocker, in the treatment of duodenal ulcer (DU) compared with lansoprazole. METHODS: A randomized, double-blind, double-dummy, multicenter, low-dose, high-dose, and positive-drug parallel-controlled study was conducted to verify the non-inferiority of keverprazan (20 or 30 mg) to lansoprazole of 30 mg once daily for 4 to 6 weeks and dose-effect relationship of keverprazan in the treatment of patients with active DU confirmed by endoscopy. RESULTS: Of the 180 subjects randomized, including 55 cases in the keverprazan_20 mg group, 61 cases in the keverprazan_30 mg group, and 64 cases in the lansoprazole_30 mg group, 168 subjects (93.33%) completed the study. The proportions of healed DU subjects in the keverprazan_20 mg, keverprazan_30 mg, and lansoprazole_30 mg groups were respectively 87.27%, 90.16%, and 79.69% at week 4 (P = 0.4595) and were respectively 96.36%, 98.36%, and 92.19% at week 6 (P = 0.2577). The incidence of adverse events in the keverprazan_20 mg group was lower than that in the lansoprazole_30 mg (P = 0.0285) and keverprazan_30 mg groups (P = 0.0398). CONCLUSIONS: Keverprazan was effective and non-inferior to lansoprazole in healing DU. Based on the comparable efficacy and safety data, keverprazan of 20 mg once daily is recommended for the follow-up study of acid-related disorders. (Trial registration number: ChiCTR2100043455.).

Clinicopathological features of esophageal schwannomas in mainland China: systematic review of the literature.

OBJECTIVE: Esophageal schwannoma (ES) are rare and mostly benign neurogenic tumors. The clinical misdiagnosis rate of it is high. In this study, the clinicopathologic features of ES in mainland China were studied to better understand the disease and improve the diagnosis and treatment rate. METHODS: A systematic review was conducted in accordance with PRISMA guidelines. The keywords "esophageal schwannoma", "esophageal neurinoma" and "esophageal neurilemoma" were searched for databases such as Pubmed, EMbase, Wanfang Database and Chinese National Knowledge Infrastructure. The search time frame for database was until July 2019. Combined with our patient, the clinicopathological data and the diagnosis and treatment of ES were summarized. RESULTS: ES occurs in the upper part of the mediastinum and in the thoracic esophagus in most patients in the neck, upper and middle segments. CT and PET/CT examinations can be used for diagnosis, but the differentiation value of both benign and malignant ES is similar. The histopathological findings of forceps biopsy specimens are often difficult to diagnose, and deep tissue biopsies may increase pathological accuracy. EUS-FNA is also recommended for ES diagnosis, but it may also be misdiagnosed. Pathological features include a fusiform arrangement in a palisade-like structure or a tumor cell arranged in a network to form a loose structure. ES characteristic immunohistochemistry results showed that S-100 protein has strong immunological activity. CONCLUSION: The definitive diagnosis requires immunohistochemistry, especially immunological reaction with S-100 protein. The appropriate treatment plan should be selected according to the diameter of the lesion. The overall prognosis of ES is good, but attention should be paid to follow-up.

Prediction of lymph node metastasis in superficial esophageal squamous cell carcinoma in Asia: a systematic review and meta-analysis.

A less invasive endoscopic therapy has been used as a routine treatment for superficial esophageal squamous cell carcinoma (SESCC). However, lymph node metastasis (LNM) in SESCC limits the effectiveness of this medical procedure. This meta-analysis aimed to screen the risk factors for LNM in SESCC in Asia to provide evidence for clinicians in selecting treatment. We searched the main reference databases for research involving patients who received esophagectomy (open or minimally invasive) with lymph node dissection for SESCC. Meta-analysis was performed using RevMan 5.3 software. Twenty studies including 3983 patients were obtained in this analysis. The meta-analysis showed that tumor size, macroscopic type of tumor, degree of differentiation, depth of tumor invasion, and lymphovascular involvement are risk factors of LNM in SESCC, whereas age, sex, and tumor location showed no association with LNM. Five variables were screened as predictive factors for LNM in SESCC. The incidence of LNM in SESCC is not rare, and the physicians must be careful when making clinical decisions.

Efficacy and Safety of Keverprazan Compared With Lansoprazole in the Treatment of Duodenal Ulcer: A Phase III, Randomized, Double-Blind, Multicenter Trial.

INTRODUCTION: Keverprazan is a novel potassium-competitive acid blocker for the treatment of acid-related disorders requiring potent acid inhibition. This study aimed to establish the noninferiority of keverprazan to lansoprazole in the treatment of patients with duodenal ulcer (DU). METHODS: In this phase III, double-blind, multicenter study, 360 Chinese patients with endoscopically confirmed active DU were randomized 1:1 to take either keverprazan (20 mg) or lansoprazole (30 mg) treatment for up to 6 weeks. The primary end point was DU healing rate at week 6. The secondary end point was DU healing rate at week 4. Symptom improvement and safety were also assessed. RESULTS: Based on the full analysis set, the cumulative healing rates at week 6 were 94.4% (170/180) and 93.3% (166/178) for keverprazan and lansoprazole, respectively (difference: 1.2%; 95% confidence intervel: -4.0%-6.5%). At week 4, the respective healing rates were 83.9% (151/180) and 80.3% (143/178). In the per protocol set, the 6-week healing rates in keverprazan and lansoprazole groups were 98.2% (163/166) and 97.6% (163/167), respectively (difference: 0.6%; 95% confidence intervel: -3.1%-4.4%); the 4-week healing rates were respectively 86.8% (144/166) and 85.6% (143/167). Keverprazan was noninferior to lansoprazole in DU healing after the treatment for 4 and 6 weeks. The incidence of treatment-emergent adverse events was comparable among groups. DISCUSSION: Keverprazan 20 mg had a good safety profile and was noninferior to lansoprazole 30 mg once daily for DU healing.

Self-made wire loop snare successfully treats gastric persimmon stone under endoscopy.

BACKGROUND: Large gastric persimmon stones are generally resistant to standard endoscopic treatments. We applied an alternative endoscopic method using a hand-made snare for the treatment of large gastric phytobezoars. AIM: To explore the clinical efficacy of a self-made wire loop snare to treat giant gastric persimmon stones. METHODS: A retrospective study evaluated the clinical data of 38 patients with gastroliths admitted to Taihe Hospital in Shiyan City, Hubei Province, China, between March 2015 and October 2020. The patients were divided into observation (n = 23) and control (n = 15) groups. Patients in the observation group were treated with self-made wire loop snares for lithotripsy, and patients in the control group were treated with traditional foreign body forceps, snares, injection needles, and other tools. Successful stone removal, treatment time, and hospital stay were compared. RESULTS: The average operating time was significantly shorter (P < 0.001) in the observation group (53.4 min) than that in the control group (172.8 min). The average hospital stay of the observation group (5.4 d) was significantly shorter (P < 0.001) than that in the control group (10.3 d). Successful one-time treatment was significantly more frequent (P < 0.001) in the observation group (87%) than in the control group (7%). CONCLUSION: Self-made guidewire loop snares were successfully used to treat gastrolithiasis, and were significantly more effective than foreign body forceps, snares, and other traditional methods.

Preoperative Neutrophil Lymphocyte Ratio Can Be Used as a Predictor of Prognosis in Patients With Adenocarcinoma of the Esophagogastric Junction: A Systematic Review and Meta Analysis.

Objective: Neutrophil lymphocyte ratio (NLR), Lymphocyte mononuclear cell ratio (LMR), and Platelet lymphocyte ratio (PLR) can be used as various prognostic factors for malignant tumors, but the value of prognosis for patients with adenocarcinoma of the esophagogastric junction (AEG) has not been determined. This study used meta-analysis to assess the value of these indicators in the evaluation of AEG prognosis. Methods: Relevant literatures on the prognostic relationship between NLR, LMR, PLR, and AEG was retrieved from PubMed, Web of Science, Embase, Cochrane Library, Cochrane Central Register of Controlled Trials, Wanfang data, and Chinese National Knowledge Infrastructure. The search time from database establishment to June 30, 2019. The language is limited to English and Chinese. Data was analyzed using Stata 15.0 software. Result: Six retrospective studies were included, five of them involved NLR and six of them involved PLR. No LMR literature that adequately satisfied the conditions was retrieved. Increased NLR was significantly associated with a significant reduction in overall survival (OS), cancer-specific survival (CSS), or disease specific survival (DSS) in patients with AEG [hazard ratio (HR) = 1.545, 95% CI: 1.096-2.179, P < 0.05]. Subgroup analysis showed that NLR had significant value in the prognosis of both Chinese and Non-Chinese patients (P = 0.009 vs. P = 0.000). NLR had significant prognostic value for ≥3 and <3 groups (P = 0.022 vs. P = 0.000). NLR has a significant prognostic value for samples ≥500 and <500 (P = 0.000 vs. P = 0.022). NLR and OS/CSS/DSS single factor meta-regression showed that regional NLR cut-off values and sample size may be the source of heterogeneity in AEG patients (all P < 0.05). There was no significant association between elevated PLR and OS in patients with AEG (HR = 1.117, 95% CI: 0.960-1.300, P > 0.05). PLR had no significant prognostic value for both Chinese and UK patients (P = 0.282 vs. P = 0.429). PLR had no significant prognostic value for ≥150 group and <150 group (P = 0.141 and P = 0.724). No significant prognostic value was found in either the 300 group and <300 group (P = 0.282 vs. P = 0.429). Conclusion: Preoperative NLR rise was an adverse prognostic indicator of AEG. High-risk patients should be treated promptly. The results showed that PLR was not recommended as a prognostic indicator of AEG.

Serum pepsinogen assay is not recommended for the diagnosis of esophageal squamous cell carcinoma: a systematic review and meta-analysis.

Background: Serum pepsinogen I (PGI) concentration and PGI/PGII ratio (PGR) are often used as serological markers for gastric fundus atrophy (AGA) and gastric carcinoma. However, their diagnostic value in esophageal carcinoma (EC) is inaccurate. Methods: This study evaluated the diagnostic value of PGI and PGR in EC by searching the PubMed, Web of Science, Embase, Cochrane Library and Cochrane Central Register of Controlled Trials databases for literature on the diagnosis of EC with PGI and PGR from January 1, 2000 to October 2, 2018. The included literature were systematically evaluated using QUSDAS-2 software. Meta-analysis was conducted using STATA 15.0 software. The summary receiver operating characteristic curve (SROC) accuracy was plotted, the area under the curve was calculated. Results: A total of 84 papers were selected, and after screening, nine papers on esophageal squamous cell carcinoma (ESCC) were finally included. Results showed low an ESCC-specific diagnostic sensitivity (0.27), high specificity (0.85), and 0.63 AUC of SROC when PGI≤70 ng/mL. When PGR≤3, the ESCC-specific diagnostic sensitivity was low (0.29), the specificity was high (0.83), and the AUC of SROC was 0.63. Conclusion: According to the current research results, PGI≤70 ng/mL or PGR≤3 diagnostic ESCC sensitivity is low, and specificity is high. These findings indicate that neither PGI≤70 ng/mL nor PGR≤3 can be used as an ESCC-screening index.

Octamer binding transcription factor-4 expression is associated with cervical cancer malignancy and histological differentiation: a systematic review and meta-analysis.

Objective: In this work, the relationship between octamer binding transcription factor 4 (OCT-4) expression and the clinicopathological features of cervical cancer (CC) is evaluated in detail.Methods: The library databases Pubmed, Embase, Cochrane library, Wan Fang and Chinese National Knowledge Infrastructure (CNKI) were searched for research related to these concepts published from the time the databases were established until May 2018. The obtained studies are screened, extracted, and evaluated according to the inclusion and exclusion criteria, and meta-analysis is carried out via RevMan 5.3.Results: Ten case-control studies, including 408 cases of CC, 164 cases of cervical intraepithelial neoplasia (CIN), and 148 cases of normal cervix, are included in the analysis. Results show that OCT-4 levels are statistically significantly different between the CC and normal cervical tissue groups (odds ratio (OR) = 15.59, 95% confidence interval (CI): 8.70, 27.94), the CC and CIN groups (OR = 5.64, 95% CI: 3.23, 9.86), the CIN and normal cervical tissues groups (OR = 7.13, 95% CI: 2.41, 21.05), and the CC well/moderately differentiated and poorly differentiated groups (OR = 0.44, 95% CI: 0.24, 0.81). OCT-4 is not statistically significantly different between CIN I + II and CIN III tissues (OR = 0.40, 95% CI: -0.02, 0.81), the CC lymphatic and non-lymphatic metastasis groups (OR = 1.93, 95% CI: 0.83, 4.47), the FIGO I and FIGO II groups (OR = 0.79, 95% CI: 0.29, 2.13), and the adenocarcinoma and squamous cell carcinoma groups (OR = 1.55, 95% CI: 0.70, 3.44).Conclusions: The available evidence suggests that OCT-4 expression is associated with CC malignancy and histological differentiation. This finding, however, is subject to quantitative studies and quality tests.

The potential role of P.gingivalis in gastrointestinal cancer: a mini review.

Bacterial infection may be involved in the entire process of tissue carcinogenesis by directly or indirectly affecting the occurrence and development of tumors. Porphyromonas gingivalis (P.gingivalis) is an important pathogen causing periodontitis. Periodontitis may promote the occurrence of various tumors. Gastrointestinal tumors are common malignant tumors with high morbidity, high mortality, and low early diagnosis rate. With the rapid development of molecularbiotechnology, the role of P.gingivalis in digestive tract tumors has been increasingly explored. This article reviews the correlation between P.gingivalis and gastrointestinal cancer and the pathogenesis of the latter. The relationship among P.gingivalis, periodontal disease, and digestive tract tumors must be clarifiedthrough a multi-center, prospective, large-scale study.

An improved surgical procedure to establish a gastroesophageal reflux model with a high incidence of Barrett's esophagus in rats.

Barrett's esophagus (BE) is a complication of gastroesophageal reflux disease and is a precursor lesion of esophageal adenocarcinoma. In existing BE models, the incidence of BE is typically low and induction is usually time consuming. In the present study, a gastroesophageal reflux model with a high incidence of BE in rats. Rats were divided into a model group and a sham operation group, and anesthetized with an inhalation anesthesia machine. Stomach-jejunal anastomosis (SJA) and esophagus-jejunal anastomosis (EJA) were simultaneously performed in the model group. The distance between the Treitz ligament and the gastro-jejunal anastomosis was shortened to 3 cm. The distance between the SJA and the EJA was prolonged to 1-1.5 cm. However, 15/40 rats in the model group succumbed to post-surgical complications (mortality rate was 37.5%). The weight of surviving rats in the model group was significantly lower compared with the sham group rats post-surgery. Erosions and ulcers were common of the surviving rats in the model group, with an incidence of 80% (20/25). Squamous cell dysplasia was identified in 40% (10/25) of rats in model group. The modified model was well established within 16 weeks. Notably, the modified surgical procedure used enhanced the incidence of BE in rats from 47% in the EJGJ model (as establish by Zhang) to 100%. To conclude, this model can be used as a reliable animal model for basic research on BE.

Combined detection of IL-6 and IL-8 is beneficial to the diagnosis of early stage esophageal squamous cell cancer: a preliminary study based on the screening of serum markers using protein chips.

BACKGROUND: The diagnosis rate of early stage esophageal squamous cell carcinoma (ESCC) is low due to the lack of specific tumor markers. Seeking for these markers is beneficial to improve the early diagnosis rate and the prognosis of patients. This study profiles the differentially expressed proteins of early stage ESCC patients via the AAH-BLG-507 protein chip, which further consolidates the clinical evidence of ESCC diagnosis. MATERIALS AND METHODS: In this study, 20 serum samples were collected from Taihe Hospital between August 2016 and June 2017. Ten of them carried ESCC, while the rest were healthy controls. To profile the proteins' expression level, the AAH-BLG-507 protein chip was used, and both highly expressed and lowly expressed proteins were fished out. Meanwhile, their biological roles were examined by using Gene Ontology (GO) database and String database, and they were further verified by ELISA. RESULTS: Results showed that the expression levels of AXL, ARTN, Ang2, BDNF, BMP7, cripto-1, CCL28, E-selectin, IL-6, IL-8 and SHH in the serum of early ESCC were significantly upregulated (P<0.05), particularly IL-6 and IL-8. The expression levels of TSP1 and MMP-8 were markedly downregulated (P<0.05). Analysis showed that these proteins were mainly involved in angiogenesis, signal transduction, cell proliferation and migration, indicating the close relationship with the development of ESCC. CONCLUSION: It suggested that IL-6 and IL-8 proteins could be considered as the markers for ESCC diagnosis.

DEPTOR suppresses the progression of esophageal squamous cell carcinoma and predicts poor prognosis.

As a naturally occurring inhibitor of mTOR, accumulated evidence has suggested that DEPTOR plays a pivotal role in suppressing the progression of human malignances. However, the function of DEPTOR in the development of esophageal squamous cell carcinoma (ESCC) is still unclear. Here we report that the expression of DEPTOR is significantly reduced in tumor tissues derived from human patients with ESCC, and the downregulation of DEPTOR predicts a poor prognosis of ESCC patients. In addition, we found that the expression of DEPTOR negatively regulates the tumorigenic activities of ESCC cell lines (KYSE150, KYSE510 and KYSE190). Furthermore, ectopic DEPTOR expression caused a significant suppression of the cellular proliferation, migration and invasion of KYSE150 cells, which has the lowest expression level of DEPTOR in the three cell lines. Meanwhile, CRISPR/Cas9 mediated knockout of DEPTOR in KYSE-510 cells significantly promoted cellular proliferation, migration and invasion. In addition, in vivo assays further revealed that tumor growth was significantly inhibited in xenografts with ectopic DEPTOR expression as compared to untreated KYSE150 cells, and was markedly enhanced in DEPTOR knockout KYSE-510 cells. Biochemical studies revealed that overexpression of DEPTOR led to the suppression of AKT/mTOR pathway as evidenced by reduced phosphorylation of AKT, mTOR and downstream SGK1, indicating DEPTOR might control the progression of ESCC through AKT/mTOR signaling pathway. Thus, these findings, for the first time, demonstrated that DEPTOR inhibits the tumorigenesis of ESCC cells and might serve as a potential therapeutic target or prognostic marker for human patients with ESCC.

Effects of adenovirus-mediated human cyclooxygenase-2 antisense RNA on the growth of hepatocellular carcinoma.

AIM: To investigate the relation between the expression of cyclooxygenase-2 (COX-2) and liver cancer, to construct the recombinant adenovirus encoding human COX-2 antisense RNA, and to explore its effects on liver cancer cell proliferation. METHODS: We studied the expression of COX-2 in 34 cases of hepatocellular carcinoma (HCC) and SMMC7402 and SMMC7721 by immunohistochemical technique. Recombinant adenovirus Ad-AShcox-2 was constructed and transfected into human HCC cell lines SMMC7402 and SMMC7721, and its effects on COX-2 expression, cell apoptosis and cell cycle were analyzed by flow cytometry. Cell proliferation was determined by colony-forming efficiency. RESULTS: We observed COX-2 expression in 82.4% of the HCC and SMMC7402 cells, but no COX-2 expression in SMMC7721 cells. In addition, recombinant adenovirus encoding antisense COX-2 fragment Ad-AShcox-2 was obtained with the titer of 1.06 x 10(12) PFU/mL. Ad-AShcox-2 could reduce the expression of COX-2 and enhance the percentage of cells in G(1)/G(0) phase in SMMC7402 cell line. The difference of apoptotic index between the Ad-AShcox-2 group and control group was statistically significant (t( control group ) = 32.62 and t( Ad-LacZ ) = 10.93, P<0.001) in SMMC7402 but not in SMMC7721. Similarly, colony-forming rates of SMMC7402 and SMMC7721 cell lines, after the transfer of Ad-AShcox-2, were (2.7+/-0.94)% and (33.6+/-4.24)%, respectively. CONCLUSION: Reduction in the expression of COX-2 can inhibit COX-2 expressing HCC cells.

Adenovirus expressing p27kip1 suppresses growth of established esophageal carcinoma xenografts.

AIM: To investigate the growth suppression of adenovirus expressing p27(kip1) on established esophageal tumors in nude mice. METHODS: Esophageal carcinoma xenografts in nude mice were established by tumor tissue mass transplantation. The successfully constructed recombinant adenoviral vectors carrying p27(kip1) gene (Ad-p27(kip1)) were directly injected into the esophageal tumors in nude mice. Compared to control group, the growth curve of tumor was drawn and the growth inhibition rate of tumor was calculated. The histology of tumors was examined by hematoxylin and eosin (H&E) staining. The expression of p27(kip1) and survivin was detected in tumors by immunohistochemical technique. RESULTS: The growth of tumors in gene therapy group with Ad-p27(kip1) was obviously suppressed compared to control group (0.42+/- 0.08 g vs 1.17+/- 0.30 g, t=6.39, P< 0.01), the inhibition rate of tumor growth reached 64.1%. Pathological detection showed that the tumors in nude mice were poorly differentiated esophageal squamous carcinoma. In addition, the expression of p27(kip1) was increased, while the expression of survivin was decreased in tumors after being transfected with Ad-p27(kip1). CONCLUSION: p27(kip1) gene therapy mediated by adenovirus vector has a significant inhibitory effect on esophageal carcinoma in vivo. Up-regulated p27(kip1) expression and down-regulated survivin expression may be its important mechanisms.

[The effects of adenovirus-mediated human COX-2 antisense RNA on the growth of hepatocellular carcinoma].

OBJECTIVE: To investigate the relationship between the expression of COX-2 and liver cancer and construct a recombinant adenovirus encoding human COX-2 antisense RNA, and then to investigate its effects on liver cancer cell proliferation. METHODS: The expression of COX-2 in 34 cases of hepatocellular carcinoma and in SMMC-7402 and SMMC-7721 cell lines was studied by using immunohistochemical techniques. The shuttle plasmid encoding anti-sense COX-2 was constructed by using cloning COX-2 cDNA fragment in the reverse direction into the pHCMVSPIA. Then the plasmid pJM17 and the shuttle plasmid were co-transferred into 293 cells with lipofectamine for homologous recombination to acquire recombinant adenovirus (Ad-AShcox-2), which was confirmed by PCR. Human hepatocellular carcinoma cell lines SMMC-7402 and SMMC-7721 were transduced in vitro. The cell apoptosis and cell cycle were analyzed by flow cytometry. The cell proliferation was determined by colony-forming efficiency. RESULTS: We observed COX-2 expression in 82.4% of the hepatocellular carcinomas and SMMC-7402 cell line, but no COX-2 expression in the SMMC-7721 cell line. In addition, the recombinant adenovirus encoding anti-sense COX-2 fragment Ad-AShcox-2 was obtained with a titer of 1.06 x 10(12) PFU/ml. Ad-AShcox-2 reduced the expression of COX-2 and enhanced the percentage of cells into G1/G0 phase in the SMMC-7402 cell line. The difference of apoptotic index between the Ad-AShcox-2 group and the control group was statistically significant in SMMC-7402 but not in SMMC-7721. Similarly, colony-forming rates of SMMC-7402 and SMMC-7721 cell lines after Ad-AShcox-2 being transferred were (2.7+/-0.94)% and (33.6+/-4.24)%, respectively. CONCLUSION: By reducing the expression of COX-2 in hepatocellular carcinoma cells with the expression of COX-2, the cells could be inhibited.

Inhibitory effect of ubiquitin-proteasome pathway on proliferation of esophageal carcinoma cells.

AIM: To investigate the inhibitory effect of ubiquitin-proteasome pathway (UPP) on proliferation of esophageal carcinoma cells. METHODS: Esophageal carcinoma cell strain EC9706 was treated with MG-132 to inhibit its UPP specificity. Cell growth suppression was evaluated with 3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay. DNA synthesis was evaluated by (3)H-thymidine ((3)H-TdR) incorporation. Morphologic changes of cells were observed under microscope. Activity of telomerase was examined by telomeric repeat amplification protocol (TRAP) of PCR-ELISA. Cell cycle and apoptosis were detected by flow cytometry (FCM). DNA fragment analysis was used to confirm the presence of apoptosis. Expression of p27(kip1) was detected by immunocytochemical technique. RESULTS: After exposed to MG-132, the growth and value of (3)H-TdR incorporation of EC9706 cells were obviously inhibited. Cells became round, small and exfoliative under microscope. TRAP PCR-ELISA showed that light absorption of cells gradually decreased after exposed to 5 micromol/L of MG-132 for 24, 48, 72 and 96 h (P<0.01). The percentage of cells at G(0)/G(1) phase was increased and that at S and G(2)/M was decreased (P<0.01). The rate of apoptotic cells treated with 5 micromol/L of MG-132 for 48 and 96 h was 31.7% and 66.4%, respectively. Agarose electrophoresis showed marked ladders. In addition, the positive signals of p27(kip1) were located in cytoplasm and nuclei in MG-132 group in contrast to cytoplasm staining in control group. CONCLUSION: MG-132 can obviously inhibit proliferation of EC9706 cells and induce apoptosis. The mechanisms include upregulation of p27(kip1) expression, G(1) arrest and depression of telomerase activity. The results indicate that inhibiting UPP is a novel strategy for esophageal carcinoma therapy.