Bile salts inhibit growth and induce apoptosis of human esophageal cancer cell line

AIM： To explore the effect of six bile salts, including glycocholate （GC）, glycochenodeoxycholate （GCEX：）, glycodeoxycholate （GDC）, taurocholate （TC）, taurochenodeoxycholate （TCDC）, taurodeoxycholate （TDC）, and two bile acids including cholic acid （CA） and deoxycholic acid （DCA） on esophageal cancer Eca109 cell line. METHODS： Eca109 cells were exposed to six bile salts, two bile adds and the mixed bile salts at different concentrations for 24-72 h. 3-[4,5-Dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide （MTT） assay was used to detect the cell proliferation. Apoptotic morphology was observed by phase-contrast video microscopy and deoxynucleotidyl transferase-mediated dUTP nick end labeling （TUNEL） assay. Sub-G1 DNA fragmentations and early apoptosis cells were assayed by flow cytometry （FCM） with propidium iodide （PI） staining and annexin V-FITC conjugated with PI staining. Apoptosis DNA ladders on agarose were observed. Activation of caspase-3 was assayed by FCM with FITC-conjugated monodonal rabbit anti-active caspase- 3 antibody and expressions of Bcl-2 and Bax proteins were examined immunocytochemically in 500μmol/L-TCinduced apoptosis cells. RESULTS： Five bile salts except for GC, and two bile acids and the mixed bile salts could initiate growth inhibition of Ecal09 cells in a dose- and time-dependent manner. TUNEL, FCM, and DNA ladder assays all demonstrated apoptosis induced by bile salts and bile acids at 500 μmol/L, except for GC. Early apoptosis cell percentages in Eca109 cells treated with GCDC, GDC, TC, TCDC, TDC, CA at 500 μmol/L for 12 h, DCA at 500 μmol/L for 6 h, and mixed bile salts at 1 000 μmol/L for 12 h were 7.5%, 8.7%, 14.8%, 8.9%, 7.8%, 9.3%, 22.6% and 12.5%, respectively, all were significantly higher than that in control （1.9%）. About 22% of the cell population treated with TC at 500 μmol/L for 24 h had detectable active caspase-3, and were higher than that in the control （1%）. Immunocytochemical assay suggested that TC down-regulated Bcl-2 protein level and up-regulated Bax protein level. CONCLUSION： GCDC, GDC, TC, TCDC, TDC, CA and DCA, except for GC, can inhibit growth and induce apoptosis of esophageal cancer Eca109 cells. Activation of caspase-3, decreased Bcl-2 protein and increased Bax protein are involved in TC-induced apoptosis of Eca109 cells.

Study on effect of BSO on esophageal cancer cell line TE-1

Objective: The aim of the study was to investigate the sensitizing effect of buthionine sulfoximine (BSO) and radiation on esophageal cancer cell line TE-1. Methods: Methyl thiazolyl tetrazolium (MTT) assay was used to observe the inhibition of BSO and radiation on cell proliferation, and to investigate the sensitizing effect of BSO on esophageal cancer cell line TE-1. Flow cytometry (FCM) was used to observe the effect of BSO and radiation on cell apoptosis and cycle. Reverse transcription polymerase chain reaction (RT-PCR) and Western blot were used to observe the effect of BSO on manganese superoxide dismutase (MnSOD) mRNA and protein expression. Results: BSO could inhibit the proliferation of TE-1 esophageal cancer cells, and had significant dose- and time-dependent radiosensitizing effects on TE-1 esophageal cancer cells. After the combined effects of BSO and radiation on TE-1 cells, the rate of apoptosis and G2/M phase proportion increased significantly, and MnSOD mRNA and protein expression decreased. Conclusion: BSO may reduce MnSOD mRNA and protein expression by affecting TE-1 cell cycle, thus inhibiting and inducing the apoptosis of esophageal cancer cells and enhancing the killing effect of the radiation on esophageal cancer cells.

EXPRESSION OF PLACENTAL ALKALINE PHOSPHATASE IN ESOPHAGEAL CANCER CELL LINE Eca109

The expression and properties of alkaline phosphatase (ALP) in Eca109 cells, a cell line derived fromhuman esophageal cancer were studied with specific inhibition assay and polyacrylamide gel electrophoresis.The results showed that ALP of Eca109 cells was heat stable and was strongly inhibited by L-pheuylalanine, but slightly inhibited by urea. Preduisolone could causedramatic increase in activity of ALP, but no change in ALP isozyme and concomitant increase in lactic dehydrogenase activity were found after prednisolone treatment. The results suggested that placental alkaline phosphatase as an oncodevelopmental gene product could be expressed ectopically by Eca109 cells and prednisolone could specifically induce increase in its activity.

Linked color imaging vs Lugol chromoendoscopy for esophageal squamous cell cancer and precancerous lesion screening: A noninferiority study

BACKGROUND Lugol chromoendoscopy(LCE)has served as a standard screening technique in high-risk patients with esophageal cancer.Nevertheless,LCE is not suitable for general population screening given its side effects.Linked color imaging(LCI)is a novel image-enhanced endoscopic technique that can distinguish subtle differences in mucosal color.AIM To compare the diagnostic performance of LCI with LCE in detecting esophageal squamous cell cancer and precancerous lesions and to evaluate whether LCE can be replaced by LCI in detecting esophageal neoplastic lesions.METHODS In this prospective study,we enrolled 543 patients who underwent white light imaging(WLI),LCI and LCE successively.We compared the sensitivity and specificity of LCI and LCE in the detection of esophageal neoplastic lesions.Clinicopathological features and color analysis of lesions were assessed.RESULTS In total,43 patients(45 neoplastic lesions)were analyzed.Among them,36 patients(38 neoplastic lesions)were diagnosed with LCI,and 39 patients(41 neoplastic lesions)were diagnosed with LCE.The sensitivity of LCI was similar to that of LCE(83.7%vs 90.7%,P=0.520),whereas the specificity of LCI was greater than that of LCE(92.4%vs 87.0%,P=0.007).The LCI procedure time in the esophageal examination was significantly shorter than that of LCE[42(34,50)s vs 160(130,189)s,P<0.001].The color difference between the lesion and surrounding mucosa in LCI was significantly greater than that observed with WLI.However,the color difference in LCI was similar in different pathological types of esophageal squamous cell cancer.CONCLUSION LCI offers greater specificity than LCE in the detection of esophageal squamous cell cancer and precancerous lesions,and LCI represents a promising screening strategy for general populations.

Relationship between genetic polymorphisms of metabolizing enzymes CYP2E1, GSTM1 and Kazakh's esophageal squamous cell cancer in Xinjiang, China

AIM: To analyze the relationship between genetic polymorphisms of metabolizing enzymes CYP2E1, GSTM1 andKazakh's esophageal squamous cell cancer in China.METHODS: The genotypes of cytochromes P450 (CYP) 2E1 and glutathione S-transferase (GST) M1 were investigated by polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) following PCR in 104 Kazakh's patients with esophageal cancer (EC) and 104 non-cancer controls.RESULTS: The frequency of CYP2E1 c1/c1 genotype was significantly higher in patients with cancer (77.9%) thanin control subjects (24.0%) (P＜0.05; OR, 11.13; 95%CI,5.84-21.22). The difference of GSTM1 null was significantly more frequent in the cancer (34.6%) vsthe control group (3.8%) (P＜0.05; OR, 13.24; 95%CI, 4.50-38.89). On the other hand, the combination of GSTM1 presence and CYP2E1 c1/c1 genotypes increased the risk for cancer (P＜0.05;OR, 13.42; 95%CI, 6.29-28.3).CONCLUSION: The CYP2E1 c1/c1, GSTM1 deletion genotypes are genetically susceptible biomarkers for ESCC in Kazakh population. Individuals with allele c1 of RsaI polymorphic locus for CYP2E1 may increase the risk of ESCC. Moreover, CYP2E1 wild type (c1/c1) increased thesusceptibility to ESCC risk in Kazakh individuals with GSTM1 presence genotype.

Expression of heparanase mRNA in anti-sense oligonucleotide-transfected human esophageal cancer EC9706 cells

AIM： To investigate the effed3 of anti-sense oligonucleotides （ASODNs） on mRNA expression of heparanase in human esophageal cancer EC9706 cells. METHODS： One non-sense oligonucleotide （N-ODN） and five ASODNs against different heparanase mRNA sites were transfected into EC9706 cells, then the expression of heparanase mRNA in EC9706 cells was studied by in situ hybridization. RESULTS： The expression of heparanase mRNA could be inhibited by ASODNs.There was no significant difference among five ASODNs （P〉0.05）, but there was a significant difference between ASODNs and N-ODN or non-transfected group （ASODNI： 2.25±0.25, ASODN2： 2.21±0.23, ASODN3： 2.23±0.23, ASODN4：2.25±0.24 vs N-ODN： 3.47±2.80 or non- transfected group： 3.51±2.93 respectively, P〈0.05）. CONCLUSION： The expression of heparanase mRNA in EC9706 cells can be inhibited by ASODNs in vivo, and heparanase ASODNs can inhibit metastasis of esophageal squamous cell carcinoma or other tumors by inhibiting the expression of heparanase.

Correlation between circulating myeloid-derived suppressor cells and Th17 cells in esophageal cancer

AIM: To perform a comprehensive investigation into the potential correlation between circulating myeloidderived suppressor cells (MDSCs) and Th17 cells in esophageal cancer (ECA). METHODS: A total of 31 patients newly diagnosed with ECA and 26 healthy subjects were included in the current study. The frequencies of MDSCs and Th17 cells in peripheral blood were determined by flow cytometry. The mRNA expression of cytokines, arginase 1 (Arg1) and inducible NO synthase (iNOS) in peripheral blood mononuclear cells (PBMCs) and plasma Arg1 were assessed by real-time polymerase chain reaction and enzyme-linked immunosorbent assay, respectively. RESULTS: There was an increased prevalence of MDSCs in the peripheral blood from ECA patients (15.21% ± 2.25%) when compared with healthy control (HC) (1.10% ± 0.12%, P < 0.0001). The plasma levels of Arg1 in ECA patients were significantly higher than those in HC (28.28 ± 4.10 ng/mL vs 9.57 ± 1.51 ng/ mL, P=0.0003). iNOS mRNA levels in the peripheral blood of ECA patients also showed a threefold increase compared with HC (P=0.0162). The frequencies of Th17 cells (CD4 + IL-17A + ) were significantly elevated in ECA patients versus HC (3.50% ± 0.33% vs 1.82% ± 0.19%, P=0.0001). Increased mRNA expression of IL-17 and ROR-γt was also observed in ECA patients compared with HC (P=0.0041 and P=0.0004, respectively), while the mRNA expression of IL-6 and tumor necrosis factor-α (TNF-α) showed significant decreases (P=0.0049 and P < 0.0001, respectively). No obvious correlations were found between the frequencies of MDSCs and Th17 cells in the peripheral blood from ECA patients(r=-0.1725, P=0.3534). Arg1 mRNA levels were positively correlated with levels of IL-6 (r=0.6404, P=0.0031) and TNF-α (r=0.7646, P=0.0001). Similarly, iNOS mRNA levels were also positively correlated with levels of IL-6 (r=0.6782, P=0.0007) and TNF-α (r=0.7633, P < 0.0001). CONCLUSION: This study reveals the relationship between circulating MDSCs and Th17 cells, which may lead to new immunotherapy approaches for ECA based on the associated metabolites and cytokines.

Molecular Mechanism of Induction on Apoptosis of Human Esophageal Cancer HCE-4 Cells by Active Components from Astragalus membranaceus

[Objectives] To investigate the pharmacologic effects of active components from A. membranaceus on human esophageal cancer HCE-4 cells and its apoptosis mechanism. [Methods] The viabilities of HCE-4 cells were measured by MTT assay. The induction of active components from A. membranaceus on apoptosis of HCE-4 cells was detected by Annexin V-FITC/PI double staining. The apoptotic-related protein expression levels were determined by Western blotting. [Results] Formononetin and astragaloside IV suppressed the proliferation of HCE-4 cells in a dose-dependent manner. The Annexin V-FITC/PI double staining results showed that formononetin and astragaloside IV could induce HCE-4 cells apoptosis in a time-dependent manner. The Western blotting results showed that formononetin and astragaloside IV could significantly down-regulate p-AKT,pro-caspase-3,and increase cle-caspase-3 protein expression in HCE-4 cells. [Conclusions]Active components from A. membranaceus such as formononetin and astragaloside IV significantly inhibited the proliferation of human esophageal cancer HCE-4 cells by inducing mitochondrial dependent apoptosis via AKT signaling pathway.

Three novel rare TP53 fusion mutations in a patient with multiple primary cancers:a case report

As survival rates improve and detection technologies advance,the occurrence of multiple primary cancers(MPCs)has been increasing.Approximately 16%of cancer survivors develop a subsequent malignancy,with lung cancer often developing after esophageal cancer due to potential“field cancerization”effects.Despite this observation,the genetic heterogeneity underlying MPCs remains understudied.However,the recent emergence of genetic testing has expanded the scope of investigations into MPCs to investigate signatures underlying cancer predisposition.This report reveals 3 unprecedented TP53 fusion mutations in a Chinese patient afflicted by MPCs,namely,AP1M2–TP53(A1;T11)fusion,TP53–ILF3(T10;I13)fusion,and SLC44A2–TP53(S5;T11)fusion.This patient exhibited an extended period of survival after diagnosis of extensive-stage small cell lung cancer,which occurred 6 years after the diagnosis of esophageal squamous cell cancer.This unique reportmay provide supplementary data that enhance our understanding of the genetic landscape ofMPCs.

Human papillomavirus in esophageal squamous cell carcinoma in Colombia and Chile

AIM： To examine the presence of human papillomavirus （HPV） in esophageal squamous cell carcinoma （ESCC） specimens collected from Colombia and Chile located in the northern and southern ends of the continent, respectively.METHODS： We examined 47 and 26 formalin-fixed and paraffin-embedded ESCC specimens from Colombia and Chile, respectively. HPV was detected using GP5＋/GP6＋ primer pair for PCR, and confirmed by Southern blot analysis. Sequencing analysis of L1 region fragment was used to identify HPV genotype. In addition, P16^INK4A protein immunostaining of all the specimens was conducted.RESULTS： HPV was detected in 21 ESCC specimens （29%）. Sequencing analysis of L1 region fragment identified HPV-16 genome in 6 Colombian cases （13%） and in 5 Chilean cases （19%）. HPV-18 was detected in i0 cases （21%） in Colombia but not in any Chilean case. Since Chilean ESCC cases had a higher prevalence of HPV-16 （without statistical significance）, but a significantly lower prevalence of HPV-18 than in Colombian cases （P = 0.011） even though the two countries have similar ESCC incidence rates, the frequency of HPV-related ESCC may not be strongly affected by risk factors affecting the incidence of ESCC. HPV-16 genome was more frequently detected in p16 positive carcinomas, although the difference was not statistically significant. HPV-18 detection rate did not show any association with p16 expression. Well-differentiated tumors tended to have either HPV-16 or HPV-18 but the association was not statistically significant. HPV genotypes other than HPV-16 or 18 were not detected in either country.CONCLUSION： HPV-16 and HPV-18 genotypes can be found in ESCC specimens collected from two South American countries. Further studies on the relationship between HPV-16 presence and p16 expression in ESCC would aid understanding of the mechanism underlying the presence of HPV in ESCC.

Plasma free amino acid profiling of esophageal cancer using high-performance liquid chromatography spectroscopy

AIM: To perform plasma free amino acid (PFAA) profiling of esophageal squamous cell carcinoma (ESCC) patients at different pathological stages and healthy subjects.

Artificial intelligence-assisted esophageal cancer management:Now and future

Esophageal cancer poses diagnostic,therapeutic and economic burdens in highrisk regions.Artificial intelligence(AI)has been developed for diagnosis and outcome prediction using various features,including clinicopathologic,radiologic,and genetic variables,which can achieve inspiring results.One of the most recent tasks of AI is to use state-of-the-art deep learning technique to detect both early esophageal squamous cell carcinoma and esophageal adenocarcinoma in Barrett’s esophagus.In this review,we aim to provide a comprehensive overview of the ways in which AI may help physicians diagnose advanced cancer and make clinical decisions based on predicted outcomes,and combine the endoscopic images to detect precancerous lesions or early cancer.Pertinent studies conducted in recent two years have surged in numbers,with large datasets and external validation from multi-centers,and have partly achieved intriguing results of expert’s performance of AI in real time.Improved pre-trained computer-aided diagnosis algorithms in the future studies with larger training and external validation datasets,aiming at real-time video processing,are imperative to produce a diagnostic efficacy similar to or even superior to experienced endoscopists.Meanwhile,supervised randomized controlled trials in real clinical practice are highly essential for a solid conclusion,which meets patient-centered satisfaction.Notably,ethical and legal issues regarding the blackbox nature of computer algorithms should be addressed,for both clinicians and regulators.

Predicting malignant transformation of esophageal squamous cell lesions by combined biomarkers in an endoscopic screening program

AIM To determine the association of p53, carcinoembryonic antigen(CEA) and CA19-9 protein expression with esophageal carcinogenesis.METHODS An iodine staining endoscopic screening program of esophageal lesions was carried out in the high-incidence area of Feicheng County, China. Seventy-seven patients with basal cell hyperplasia(BCH), 247 with low-grade dysplasia(LGD), 51 with high-grade dysplasia(HGD), 134 with invasive cancer, and 80 normal controls diagnosed by mucous membrane biopsy pathology were enrolled. Immunohistochemical detection of p53, CEA and CA19-9 proteins was performed. In the ROCcurve analysis, the expression of a single biomarker and the expression of a combination of biomarkers were used to predict the risk of these four esophageal lesions.RESULTS The positive rates of p53 protein expression in invasive cancer, HGD, LGD, BCH and the normal control groups were 53.0%, 52.9%, 35.6%, 27.3% and 20.0%, respectively; the positive rates of CA19-9 protein expression were 44.0%, 33.3%, 16.5%, 9.2% and 6.2%, respectively; the positive rates of CEA protein expression were 74.6%, 60.8%, 23.3%, 23.7% and 16.2%, respectively. The positive rates of the combined expression of the three biomarkers were 84.3%, 76.5%, 47.6%, 42.9% and 27.5%, respectively. In the receiver operating characteristic curves of the combination of the three biomarkers, the specificity was 88.8% for the normal controls, and the sensitivity was 58.2% for invasive cancer, 25.5% for HGD, 11.2% for LGD, and 6.5% for BCH.CONCLUSION p53, CEA and CA19-9 protein expression was correlated with esophageal carcinogenesis, and testing for the combination of these biomarkers is useful for identifying high-risk patients with precancerous lesions.

Prognostic and incremental value of computed tomography-based radiomics from tumor and nodal regions in esophageal squamous cell carcinoma

Objective:This study aimed to evaluate the prognostic value of preoperative radiomics and establish an integrated model for esophageal squamous cell cancer(ESCC).Methods:A total of 931 patients were retrospectively enrolled in this study(training cohort,n=624;validation cohort,n=307).Radiomics features were obtained by contrast-enhanced computed tomography(CT)before esophagectomy.A radiomics index was set based on features of tumor and reginal lymph nodes by using the least absolute shrinkage and selection operator(LASSO)Cox regression.Prognostic nomogram was built based on radiomics index and other independent risk factors.The prognostic value was assessed by using Harrell’s concordance index,time-dependent receiver operating characteristics and Kaplan-Meier curves.Results:Twelve radiomic features from tumor and lymph node regions were identified to build a radiomics index,which was significantly associated with overall survival(OS)in both training cohort and validation cohort.The radiomics index was highly correlated with clinical tumor-node-metastasis(cTNM)and pathologic TNM(pTNM)stages,but it demonstrated a better prognostic value compared with cTNM stage and was almost comparable with pTNM stage.Multivariable Cox regression showed that the radiomics index was an independent prognostic factor.An integrated model was constructed based on gender,preoperative serum sodium concentration,pTNM and the radiomics index for clinical usefulness.The integrated model demonstrated discriminatory ability better compared with the traditional clinical-pathologic model and pTNM alone,indicating incremental value for prognosis.Conclusions:CT-based radiomics for primary tumor and reginal lymph nodes was sufficient in predicting OS for patients with ESCC.The integrated model demonstrated incremental value for prognosis and was robust for clinical applications.

CLINICAL SIGNIFICANCES OF THE EXPRESSION OF METALLO- THIONEIN IN FIVE TYPES EPITHELIUM CELL CANCER

Objective： To study the expressions of （CSC）, bladder transitional cell cancer metallothionein and the significances in cervical squamous cell cancer （BTC）, esophageal squamous cell cancer （ESC）, gastral tubular adenocarcinoma （GC） and large intestinal tubular adenocarcinoma （LIC）. Methods： lmmunohistochemical method was used to examine the expression rates of MT in five types of cancer tissue. Results： The expression rates of MT were 75.00% （24/32） in ESC, 52.27% （46/88） in GTC, 59.46% （44/74） in LIC, 64.86% （48/74） in BTC and 58.57% （41/70） in CSC respectively. The positive rates of MT expression were higher in low differentiation and deep muscular group than those in medium or high differentiation and superficial muscular invasion group （P〈0.05）. Conclusion： The expression of MT is related to differentiation degree and invasion degree.

Expression of Vascular Endothelial Growth Factor C and Its Clinical Significance in Human Esophageal Squamous Cell Carcinoma

OBJECTIVE To examine the expression of vascular endothelial growth factor C （VEGF-C） in human esophageal squamous cell carcinoma （ESCC）, and to clarify its role in lymphatic metastasis in ESCC patients.METHODS Esophageal carcinoma EC9706 cells and samples from 49 patients with primary ESCC were investigated by using S-P immunohistochemistry （IHC）, the semi-quantitative reverse transcriptase-polymerase chain reaction （RT-PCR） and in situ hybridization （ISH） methods for VEGF-C expression. RESULTS VEGF-C positive expression was found in EC9706 cells through IHC, ISH and RT-PCR. Positive IHC for VEGF-C was observed in 36 of 49 cases of ESCC. There was a significant difference between the expression of VEGF-C in a lymph-node-positive group compared to a node-negative group （χ^2=4.7, P〈0.05）. Positive ISH for VEGF-C mRNA was observed in 23 of 49 cases of ESCC. There was a significant difference between the expression of VEGF-C in the lymph-node-positive group and node-negative group （χ^2=31.3, P〈0.01）. The expression of VEGF-C was significantly higher in the lymph-node-positive group compared to the node-negative group. Of 49 ESCC tissues, RT-PCR for VEGF-C mRNA was observed positively in 29 cases. There was a significant difference between the expression of VEGF-C in the lymph-node-positive group and node-negative group （χ^2=23.3, P〈0.01）. The expression of VEGF-C was significantly higher in the lymphnode-positive group compared to the node-negative group. Expressions of VEGF-C were not significantly associated with age, gender, and pathological grade. There was a relationship between VEGF-C mRNA expressions by RT-PCR and ISH （χ^2=18.5, P〈0.01） in ESCC cases, but with no significant difference between the two methods. CONCLUSION VEGF-C expression may induce lymphangiogenesis in human ESCC. There was a close correlation between VEGF-C expression and lymph node metastasis. VEGF-C can serve as a useful prognostic factor for ESCC patients.

Inhibition effects of all trans-retinoic acid on the growth and angiogenesis of esophageal squamous cell carcinoma in nude mice

Background The potential application of retinoic acid receptor activators, such as all trans-retinoic acid （ATRA）, for treating various cancers have been studied both pre-clinically and clinically. Whether ATRA has an anticancer effect on human esophageal squamous cancer cell （ESCC） is still unknown. We have explored the anticancer effect of ATRA in ESCC, and in this study, the effects of ATRA on levels and patterns of expression of the vascular endothelial growth factor （VEGF） signal transduction pathway in transplantable tumor growth of the human ESCC cell line, EC9706, in nude mice. Methods The animal model of the ESCC xenograft was made by subcutaneous implantation of tumor cells into nude mice. Reverse transcription-polymerase chain reaction （RT-PCR）, Western blotting and immunohistochemical assays were used to detect the expression of the VEGF signal transduction pathway in ESCC xenograft tissues. Results Compared to the control group, the tumor inhibition rates in the low dose ATRA, high dose ATRA, and 5-FU groups were 83.21%, 88.32%, 91.02%, respectively. The protein and mRNA levels of VEGF were down-regulated after being treated with ATRA and 5-FU compared to the control group （P 〈0.05）. The study also revealed that ATRA specifically down-regulated VEGF and the component of the VEGF signal transduction pathway of CD31, CD34, and CD105 （component of the TGF-13 receptor） in ESCC xenograft tissues （P 〈0.05）. Conclusions ATRA can significantly inhibit tumor growth and has anticancer effects on transplantable tumor growth of human ESCC cell line EC9706 in nude mice. These findings indicate that ATRA specifically down regulated VEGF and the components of VEGF signal transduction, which may be an important mechanism responsible for the neoangiogenesis inhibition of ESCC cells.

RASSF6-TRIM16 axis promotes cell proliferation,migration and invasion in esophageal squamous cell carcinoma

Ras-association(RA) domain family number 6(RASSF6) is a member of the Ras-association domain protein family.It is epigenetically inactive and negatively regulates the malignant progression of some tumors.However,its precise role in esophageal squamous cell carcinoma(ESCC) has not been reported.In this study,we performed immunohistochemistry(IHC) assay.The results show that RASSF6 is upregulated in ESCC and that the elevated expression level of RASSF6 is associated with lymph node metastasis and poor survival of ESCC patients.Consistent with the clinical obse rvations,the upregulation of RASSF6 greatly promotes ESCC cell proliferation,migration and invasion as well as the cell cycle transition to Gl/S phase in vitro.According to models in vivo,the downregulation of RASSF6 considerably inhibits ESCC tumor growth and lung metastasis.Mechanistically,RASSF6 negatively regulates the tumor suppressor tripartite-motif-containing protein 16(TRIM16) by promoting its ubiquitination-dependent degradation and eventually activates pathways associated with the cell cycle and epithelialmesenchymal transition(EMT).Together,these results indicate that the RASSF6-TRIM16 axis is a key effector in ESCC progression and that RASSF6 serves as a potential target for the treatment of ESCC.

Cytotoxic Activities of Total Saponins from Plena Clematis on Human Tumor Cell Lines In Vitro

Objective： To investigate the anti-proliferative effects of saponins prepared from Plena Clematis （PC） cultured in Fujian Province, China on 4 human tumor cell lines and its possible anti-tumor mechanism. Methods： The growth inhibition assays of saponins on human esophageal squamous carcinoma cell line （EC9706）, human hepatoma cell line （HepG-2）, human oral cancer cell line （KB） and human gastric cancer cell line （BGC-823） were evaluated in vitro by thiazolyl blue （MTT） method. The inhibitory effects on EC9706 treated with different concentrations of saponins （15.62, 31.25, 62.50, 125, 250 and 500 μg/mL） were performed in vitro by MTT method. The morphology and nuclear staining with acridine orange/ethidium bromide of EC9706 calls treated with saponins were illustrated under an inverted phase fluorescence microscope. The apoptotic effects of saponins were further evaluated by annexin-V/propidium iodide dual staining experiment to examine the occurrence of phosphatidylserine externalization onto the call surface by a flow cytometer. Results： MTT assay showed that the saponins could inhibit the proliferation of 4 tumor cell lines. Among them, the maximum inhibition rate of 73.1% was detected in EC9706 cells at the saponins concentration of 250 μg/mL for 24 h. Further investigation indicated that the saponins induced EC9706 cells apoposis. The EC9706 cells presented apoptotic characteristics when treated with saponins, including that the morphologies of EC9706 cells were appeared round-shaped with higher refraction, and the cell nuclear stained orange with EB after 250 μ g/mL saponins exposure. The flow cytometry analysis results showed that the induction of cell cycle arrest in apoptotic system may participate in the anti-proliferative activity of saponins on EC9706 cells. Conclusion： The saponins from PC exhibited significant cytotoxicity against human EC9706, KB, BGC-823, and HepG-2 cells and might be beneficial to development of ethnic pharmaceutical plant for potential anti-tumor drugs.