Esophageal Carcinoma Cell Line Eca109 Research Articles

Circ_0003855 involvement of esophageal cancer progression through miR-622/FLOT1.

To confirm the relationship between Circ_0003855 and EC, we purchased the Human esophageal carcinoma cell line Eca109 and normal human esophageal epithelial cells HEEC, and the expression levels of Circ_0003855, miR-622, and FLOT1 were detected. The results show that Circ_0003855 and FLOT1 were highly expressed in Eca109 cells, while miR-622 was lowly expressed (p < 0.05). Subsequently, Circ_0003855 small interfering RNA (si-Circ_0003855) and its negative control (si-NC) were used to detect changes in cellular biological behaviors. We found that the activity of Eca109 cells was reduced after interfering with the expression of Circ_0003855, and miR-622 expression was elevated, while FLOT1 was decreased (p < 0.05). Additionally, si-Circ_0003855 and miR-622 inhibitor sequence (miR-622-inhibition) were co-transfected into cells with miR-622-inhibition alone, and untreated Eca109 cells were used as a control to detect the expression of FLOT1. Co-transfection of si-Circ_0003855 and miR-622-inhibition showed no significant difference in FLOT1 expression compared to the control cells (p > 0.05). Synthesizing the results of these experiments above, we believe that interfering with the expression of Circ_0003855 can inhibit the activity of EC cells, and its mechanism is related to miR-622 and FLOT1.

MC1R is highly expressed in esophageal squamous cell carcinoma

To investigate the expression of MC1R in esophageal squamous cell carcinoma and its correlation with the clinicopathological parameters. We analyzed the expression of MC1R in esophageal cancer based on data from TCGA databse and examined its expression levels using RT-PCR and Western blotting in a human esophageal epithelial cell line BAr-T, human esophageal squamous cell carcinoma cell lines ECA109, KYSE30, KYSE150, KYSE510, TE-1, TE-13, and EC9706, a human gastric cancer cell line SGC7901 and 19 pairs of esophageal squamous cell carcinoma tissues and adjacent tissues.Immunohistochemistry was used to detect MC1R expression levels in 32 pairs of paraffin-embedded sections of esophageal squamous cell carcinoma and adjacent tissues, and the correlation of MC1R expression and the patients'clinicopathological characteristics was analyzed. Bioinformatics analysis showed that MC1R was significantly overexpressed in esophageal cancer tissues (P < 0.05).MC1R expression was also increased in 5 esophageal squamous cell carcinoma cell lines ECA109, KYSE30, KYSE510, TE-13, EC9706 and the gastric cancer cell line SGC7901 as compared with that in esophageal epithelial cells (P < 0.05).Immunohistochemistry revealed significantly increased MC1R expression in esophageal squamous cell carcinoma tissue sections in comparison with the adjacent tissue sections (P < 0.05).In patients with esophageal squamous cell carcinoma, a high MC1R expression was detected mainly in those with an old age, positive for middle-thoracic involvement, and with moderately differentiated tumor cells, and showed a correlation with T stage of tumor (P < 0.05), but not with the other clinicopathological parameters such as gender, age, degree of cell differentiation, primary tumor site, or TNM stage (P>0.05). MC1R is highly expressed in esophageal squamous cell carcinoma and may serve as a molecular biomarker to assist in the diagnosis of esophageal squamous cell carcinoma.

Identification and function of circular RNA hsa_circ_0071106: A novel biomarker for differentiation degree of esophageal squamous cell carcinoma

BackgroundEsophageal squamous cell carcinoma (ESCC) has a high degree of malignancy, and there is currently no effective treatment. Circular RNA is a novel endogenous noncoding RNA with a stable loop structure. Several theories have been proposed regarding its biogenesis and usefulness as a biomarker in various cancers. Here we explore the predictive value and potential functions of a candidate circRNA (hsa_circ_0071106) in ESCC. MethodsThe altered expression of hsa_circ_0071106 was validated in clinical tissue samples from 64 patients with ESCC. The correlation between the clinical characteristics of these patients and the expression of hsa_circ_0071106 was analyzed by the chi-square test. The receiver operating characteristic (ROC) curves and the area under the ROC curve (AUC) were used to evaluate the diagnostic value of hsa_circ_0071106. The human esophageal carcinoma cell lines ECA109 and ECA9706 and the normal human esophageal epithelial cell line (HET-1A) were applied for functional analysis of hsa_circ_0071106. qRT-PCR, sanger sequencing, agarose gel electrophoresis, RNase R digestion assay, Actinomycin D inhibition assay, nucleoplasm separation assay, and FISH assays were utilized to verify the circular characteristics and subcellular localization of hsa_circ_0071106. SiRNA and circRNA interference lentivirus was constructed to inhibit the expression of hsa_circ_0071106 in the ECA109 and ECA9706 cell lines. We used the EdU assay, Transwell assay, and flow cytometry to detect changes in cell proliferation, invasion, migration, and apoptosis. ResultsWe identified that hsa_circ_0071106 showed significantly decreased expression levels in ESCC cells (P < 0.001) and tissue samples (P < 0.001). The correlation analysis of clinicopathological features and gene expression revealed that low expression of hsa_circ_0071106 was related to poor differentiation grade (P < 0.05). ROC curves indicated that hsa_circ_0071106 might have a diagnostic value for ESCC (AUC = 0.826, 95% CI: 0.748–0.904) and a predictive value for a high degree of histological differentiation (AUC = 0.730, 95% CI: 0.607–0.854). Hsa_circ_0071106 has a stable circular structure and was primarily localized in the cytoplasm. A transient knockdown of hsa_circ_0071106 by siRNA promotes proliferation, migration, and invasion and inhibits apoptosis of ESCC cells. A steady knockdown of hsa_circ_0071106 by a lentivirus knockout vector significantly promoted cell migration and invasion in ECA109 and ECA9706 cell lines. ConclusionHsa_circ_0071106 was a downregulated circRNA related to ESCC and promoted ESCC progression by regulating cell migration and invasion. These findings suggest that hsa_circ_0071106 could be a promising diagnostic biomarker and potential therapeutic target and might predict ESCC’s histological differentiation degree.

Bivalent β-Carbolines Inhibit Colorectal Cancer Growth through Inducing Autophagy.

In this study, a series of alkyl diamine linked bivalent β-carbolines was synthesized and evaluated as antitumor agent. The results demonstrated that most compounds displayed good antiproliferative activities with IC50 value lower than 10 µM against a panel of human tumor cell lines, and compound 8 was found to be the most potent antiproliferative agent with IC50 value of 1.39, 1.96, 1.42, 1.49, 1.32, 1.96 and 1.63 µM against human breast cancer cell line (MCF-7), human adenocarcinoma cell line (769-P), human malighant melanoma cell line (A375), human ovarian cancer cell line (SK-OV-3), human colon carcinoma cell line (HCT-116), human gastric cancer cell line (BGC-823) and human esophageal squamous carcinoma cell line (Eca-109), respectively. Further investigations on mechanism of action of this class of compound demonstrated that the representative compound 8 inhibited colorectal cancer growth through inducing autophagy.

Effect of silencing C-erbB-2 on esophageal carcinoma cell biological behaviors by inhibiting IGF-1 pathway activation

ObjectiveC-erbB-2 has been confirmed to be an oncogene that participates in cell growth, differentiation and division of tumors. We are wondered if its silenced expression can exert an anti-tumor effect. Therefore, this study is conducted to investigate the mechanism of C-erbB-2 silencing and IGF-1 pathway on esophageal carcinoma (EC) cell biological behaviors.MethodsThe objects of study were 84 EC patients from Heping Hospital Affiliated to Changzhi Medical College, with the collection of EC tissue and adjacent normal tissue (> 5 cm away from cancer tissue). C-erbB-2 protein expression in EC tissues was detected by immunohistochemistry. Human EC cell line Eca-109 was purchased from Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences. Based on different transfection protocols, EC cells with logarithmic growth phase of 3–5 passages were divided into blank control group, oe-C-erbB-2 NC group, siRNA C-erbB-2 NC group, oe-C-erbB-2 group, siRNA C-erbB-2 group, OSI-906 group, Rg5 group, Rg5 + siRNA C-erbB-2 NC group and Rg5 + siRNA C-erbB-2 group. Cell proliferation was detected by MTT assay; cell cycle distribution and apoptosis by flow cytometry; C-erbB-2, IGF-1, IGF-1R and Akt mRNA and protein expressions by qRT-PCR and western blot; and cell invasion and migration by Transwell assay and scratch test. Tumor growth was observed in male BALB/c nude mice (Shanghai Experimental Animal Center) based on Eca109 cell implantation, raising, and measurement.ResultsC-erbB-2, IGF-1, IGF-1R and Akt expression were higher in EC tissues than those in adjacent tissues (all P < 0.05). Compared with blank control group, both si-C-erbB-2 and OSI-906 groups had decreased IGF-1, IGF-1R and Akt mRNA and protein expressions, decreased cell proliferation, migration and invasion, prolonged G0/G1 phase, shortened S phase, increased cell apoptosis, and inhibited tumor growth (all P < 0.05); while opposite trends were detected in C-erbB-2 vector and Rg5 groups (all P < 0.05), without statistical differences in siRNA C-erbB-2 + Rg5 group (all P > 0.05).ConclusionSilencing C-erbB-2 expression may inhibit EC cell proliferation, promote cell apoptosis and block cell cycle progression by inhibiting IGF-1 pathway activation. The beneficial effect of silencing C-erbB-2 expression can be reversed by promoting the activation of IGF-1 pathway. Findings in our study may provide potential reference for understanding the molecular mechanism of EC and supply possible axis for preventing the development of EC from the perspective of molecular biology.

BAP1 promotes viability and migration of ECA109 cells through KLF5/CyclinD1/FGF-BP1.

More than 40 000 patients worldwide die from esophageal cancer annually. The 5‐year survival rate of patients is only ~ 15–20%, and thus, there is an ongoing need to improve diagnosis and treatment of esophageal cancer. Breast cancer type 1 susceptibility protein (BRCA1)‐associated protein (BAP1) is a marker of poor prognosis in several cancers, including uveal melanoma, renal cell carcinoma, cholangiocarcinoma, non‐small cell lung cancer, and colorectal cancer. BAP1 mutations are early and rare events in esophageal carcinoma, but the involvement of BAP1 in progression of esophageal carcinoma is unclear. Here, we report that cell proliferation and migration were significantly enhanced in esophageal carcinoma ECA109 cells overexpressing BAP1, while they were diminished upon BAP1 knockdown. In addition, the expression of Krüppel‐like factor 5 (KLF5), CyclinD1, and FGF‐BP1 was increased by BAP1 overexpression and decreased by BAP1 knockdown. Our data suggest that BAP1 promotes cell proliferation and migration, and enhances the expression of KLF5 and its downstream genes, including CyclinD1 and FGF‐BP1, in the esophageal carcinoma cell line ECA109.

Effect of HMGB1 knockdown by RNA interference on cell proliferation and migration of esophageal squamous cell carcinoma after X-ray radiation

Objective To evaluate the effect of X-ray radiation on cell proliferation, migration, survival ability and cell cycle of human esophageal squamous cell carcinoma after RNA interference-mediated down-regulation of HMGB1 gene expression. Methods The expression of HMGB1 at mRNA and protein levels in the human esophageal squamous cell carcinoma cell lines ECA109 and KYSE30 was determined using RT-PCR and Western blot assays. MTS and Transwell assays were employed to examine the proliferation and migration of ECA109 and KYSE30 cell lines. The cellular survival ability in vitro was assessed by clone formation assay. The cell cycle after X-ray radiation in different groups was detected by flow cytometry. Results The expression of HMGB1 at mRNA and protein levels in ECA109 and KYSE30 cells were markedly higher in a dose-dependent and time-dependent manner in the radiation group than that in the control group (all P<0.05). MTS results demonstrated that the proliferation of ECA109 and KYSE30 cells was obviously lower at each time point after radiation than that in the group without radiation (all P<0.01). The expression of HMGB1 at mRNA and protein levels was significantly inhibited in the HMGB1 siRNA group than those in the control and NC groups (both P<0.01). The data from the clone formation assay revealed that the radiosensitivity was significantly increased after down-regulation of HMGB1 expression (P<0.01). Transwell migration assay revealed that the number of migrating cells at the fourth hour after X-ray irradiation in the HMGB1 siRNA group was significantly lower than those in the control and negative groups (both P<0.01). In the HMGB1 siRNA group, the percentage of cells at G0/G1 phase was obviously higher, whereas the percentage of S phase was significantly lower than those in the control and NC groups, and the trend was even more significant after X-ray radiation (all P<0.01). Conclusion Inhibition of HMGB1 expression by siRNA can suppress the proliferation and migration of ECA109 and KYSE30 cells and enhance the radiosensitivity by increasing the cell cycle arrest at G0/G1 stage after X-ray irradiation in vitro. Key words: HMGB1 gene; Cell proliferation and migration; Cell cycle; Radiosensitivity

Effects of Polygonatum sibiricum Polysaccharides (PSP) on Human Esophageal Squamous Cell Carcinoma (ESCC) via NF-κB Signaling Pathway

Objective. To explore the effects of different concentrations of Polygonatum sibiricum polysaccharides (PSP) on human esophageal squamous cell carcinoma (ESCC) cell line Eca109 and explore the new approach for the treatment of ESCC. Methods. Eca109 cells were divided into 5 groups, including one control group and 4 experimental groups where the concentrations of PSP used were 50, 100, 200, and 400 μg/mL. The proliferation rate of Eca109 cells in each group was measured with the CCK8 assay, and the apoptosis rate in each group was analyzed by flow cytometry; the in vitro scratch assay was used to determine the migration ability of Eca109 cells after PSP treatment; the expression levels of IL-1, IL-6, IL-10, TNF-α, and TGF-β were measured by RT-PCR, and the expression levels of TLR4 and proteins that are related to NF-κB signaling pathways were determined by Western blot. Results. PSP significantly inhibited the proliferation of Eca109 cells (p&lt;0.05) on a time- and dose-dependent manner; the apoptosis rates of Eca109 cells in experimental groups were significantly increased after 48 h of culture (p&lt;0.05); PSP significantly reduced the migration and invasion ability of Eca109 cells (p&lt;0.05); RT-PCR results showed that the expression of IL-10 in Eca109 cells increased significantly after treatment with PSP (p&lt;0.05), while the expression of IL-1, IL-6, TNF-α, and TGF-β decreased significantly (p&lt;0.05). Compared with the control group, the expression level of TLR4, NF-κB/p50, and NF-κB/p65 protein in each experimental group was significantly lower than that in the control group (p&lt;0.05). Conclusions. PSP significantly inhibited the proliferation, invasion, and migration of Eca109 cells and promoted cell apoptosis. These observed effects were probably due to the PSP’s inhibition on the NF-κB signaling pathway in Eca109 cells via the regulation of the TLR4 expression.

α-Hederin Induces Apoptosis of Esophageal Squamous Cell Carcinoma via an Oxidative and Mitochondrial-Dependent Pathway.

α-Hederin has been shown promising anti-tumor potential against various cancer cell lines. However, reports about effects of α-hederin on esophageal squamous cell carcinoma (ESCC) are still unavailable. To investigate the inhibitory effects of α-hederin on ESCC and explore the underlying mechanism. Human esophageal carcinoma cell line (Eca-109) was used for the experiment. Cell Counting Kit-8, flow cytometry, Hoechst 33258 staining, enhanced ATP assay kit, 2',7'-dichlorofluorescin diacetate, JC-1 kit, and Western bolt were used to assess the cell viability, cycle, apoptosis, cellular ATP content, reactive oxygen species (ROS) level, mitochondrial membrane potential (MMP), and protein expression, respectively, in vitro. Xenografted tumor model was constructed to evaluate the in vivo anti-tumor effects of α-hederin. Compared with control group, α-hederin significantly inhibited the proliferation, induced apoptosis of ESCC, and arrested the cell cycle in G1 phase (P < 0.05). α-Hederin induced the accumulation of ROS, decrement of ATP levels, and disruption of MMP (P < 0.05). The detection of mitochondrial and cytosol proteins showed that AIF, Apaf-1, and Cyt C were released and increased in cytoplasm, and then, caspase-3, caspase-9, and Bax were involved and increased, while Bcl-2 level was decreased (P < 0.05). Furthermore, the above changes were amplified in the group pretreated with L-buthionine sulfoximine, while N-acetyl-L-cysteine plays an opposite role (P < 0.05). Meanwhile, α-hederin significantly inhibited the growth of xenografted tumors with favorable safety. α-Hederin could inhibit the proliferation and induce apoptosis of ESCC via dissipation of the MMP with simultaneous ROS generation and activation of the mitochondrial pathway.

Upregulation of ID2 antagonizes arsenic trioxide-induced antitumor effects in cancer cells.

Arsenic trioxide (ATO) strongly induces apoptosis and differentiation in acute promyelocytic leukemia, and induces cell cycle arrest in most solid tumors. Although many signaling pathways are involved in its antitumor mechanism, a detailed investigation of the transforming growth factor beta-bone morphogenetic protein signaling pathway has not been performed. A microarray containing 113 genes associated with the pathway was used to screen important molecules that participate in the antitumor effects of ATO. The expression levels of the inhibitors of DNA binding-2 (ID2) in 4 different types of cancer cells were determined by quantitative reverse transcription PCR and Western blotting. Human esophageal squamous cell carcinoma cell line Eca109 and pancreatic carcinoma cell line BxPC3 cells were transfected with siRNAs targeting ID2 and scrambled control siRNA. Cell proliferation was evaluated by methyl thiazolyl tetrazolium assay. Eighteen upregulated and 12 downregulated genes were identified. After verification at the transcriptional and translational levels in 4 different cancer cells, ID2 was identified as an ATO antitumor-associated protein. In addition, specific silencing of ID2 could enhance ATO-induced cell proliferation inhibition in cancer cells. A combination of ATO and ID2-targeted agents may have considerable therapeutic benefits in cancers.

Gremlin1 Delivered by Mesenchymal Stromal Cells Promoted Epithelial-Mesenchymal Transition in Human Esophageal Squamous Cell Carcinoma

Backgroud/Aims: Mesenchymal stromal cells (MSCs) are a major component of the tumor microenvironment (TME). Several studies focusing on tumor-derived MSCs have demonstrated that they exhibit a strong ability to promote the tumor epithelial-mesenchymal transition (EMT). However, the factors mediating these effects are poorly understood. Methods: Quantitative reverse transcription-polymerase chain reaction (qRT-PCR) and immunohistochemistry assays were used to detect the expression of Gremlin1 (GREM1) in human esophageal squamous cell carcinoma (ESCC) tissues. ShRNA silencing, flow cytometry, cell counting kit (CCK8) assay, invasion assay, western blot were used to detect the effect of GREM1 in ECa109, TE-1 cell lines and xenograft tumor models. Results: In the current study, we found that the GREM1 was overexpressed in human ESCC tissues. The conditioned medium from mesenchymal stromal cells (MSCs-CM) enhanced the malignancy of xenograft esophageal tumors in vivo, as well as the cell proliferation, viability and invasion of the esophageal carcinoma cell lines ECa109 and TE-1 in vitro. Furthermore, the shRNA silencing of GREM1 in MSCs (shGREM1-MSCs) reversed the increased malignancy of the esophageal tumor in vivo, while the conditioned medium from shGREM1-MSCs (shGREM1-MSCs-CM) affected the cell cycle and cell invasion in vitro. These processes were accompanied by the EMT in the ECa109 and TE-1 cell lines with an alteration in the expression levels of mesenchymal and epithelial markers. Furthermore, the TGF-β/BMP (transforming growth factor-beta/bone morphogenetic protein) signaling pathway participated in the shGREM1-MSCs-CM-induced anti-tumor effect on enhanced esophageal malignancy induced by MSCs-CM treatment. Conclusions: Taken together, our study suggested that GREM1 delivered by MSCs promoted EMT in ESCC in vitro and in vivo, which is partly through TGF-β/BMP signaling pathway. The results provide experimental evidence to a potential therapeutic target in the treatment of esophageal cancer.

PLCE1 Promotes the Invasion and Migration of Esophageal Cancer Cells by Up-Regulating the PKCα/NF-κB Pathway.

PurposeTo investigate the effect and mechanism of phospholipase C epsilon gene 1 (PLCE1) expression on esophageal cancer cell lines.Materials and MethodsThe esophageal carcinoma cell lines Eca109 and EC9706 and normal esophageal epithelial cell line HEEC were cultured. The expression of PLCE1, protein kinase C alpha (PKCα), and nuclear factor kappa B (NF-κB) p50/p65 homodimer in cells were comparatively analyzed. The esophageal cancer cells were divided into si-PLCE1, control siRNA (scramble), and mock groups that were transfected with specific siRNA for PLCE1, control siRNA, and blank controls, respectively. Expression of PLCE1, PKCα, p50, and p65 was detected by Western blotting. Transwell assay was used to detect migration and invasion of Eca109 and EC9706 cells.ResultsCompared with HEEC, the expression of PLCE1, PKCα, p50, and p65 was increased in Eca109 and EC9706 cells. The expression of PLCE1 was positively correlated with the expression of PKCα and p50 (PKCα: r=0.6328, p=0.032; p50: r=0.6754, p=0.041). PKCα expression had a positive correlation with the expression of p50 and p65 (p50: r=0.9127, p=0.000; p65: r=0.9256, p=0.000). Down-regulation of PLCE1 significantly decreased the expression of PKCα and NF-κB-related proteins (p65: p=0.002, p=0.004; p50: p=0.005, p=0.009) and inhibited the migration and invasion of Eca109 and EC9706 cells.ConclusionPLCE1 activated NF-κB signaling by up-regulating PKCα, which could promote invasion and migration of esophageal cancer cells.

Thymoquinone Augments Cisplatin-Induced Apoptosis on Esophageal Carcinoma Through Mitigating the Activation of JAK2/STAT3 Pathway.

Thymoquinone (TQ) is the major constituent of Nigella sativa seed and has shown biological activity in various human carcinomas. However, few studies have reported its effect on esophageal carcinoma (EC). To explore the chemosensitive effect and mechanism of TQ in augmentation of cisplatin (DDP)-induced apoptosis of EC, both in vitro and in vivo. The viability and apoptosis of esophageal carcinoma cells were detected by the Cell Counting Kit-8 assay, flow cytometry, and Hoechst 33258 staining. The expression levels of JAK2, p-JAK2, STAT3, p-STAT3, Bax, Bcl-2, Cyclin D1, Survivin, and caspase-3, 7, 9 were evaluated by western blot analysis. The histological changes were examined by TUNEL technique and immunohistochemical analysis. TQ enhanced the proapoptotic effect of DDP in human esophageal carcinoma cell line Eca-109, while blocking the activation of JAK2/STAT3 signaling pathway. The apoptosis of esophageal carcinoma cells was induced via blocking the activation of JAK2/STAT3 by using a molecular inhibitor (WP1066). Consistent with the in vivo and in vitro results, TQ increased cellular apoptosis and enriched the chemosensitivity of DDP. TQ along with DDP may regulate the progression of EC and has potential to be a chemotherapeutic agent in EC.

Study on the role of transient receptor potential C6 channels in esophageal squamous cell carcinoma radiosensitivity.

To study the effect of transient receptor potential C6 (TRPC6) channels on esophageal squamous cell carcinoma (ESCC) cell lines Eca109 cell cycle and to confirm whether TRPC6 channel is candidate radiosensitivity in vitro and in vivo. We chose Eca109 cell line with a strong TRPC6 channels expression. Cell cycle was investigated after TRPC6 channel inhibitor SKF96365 treated with a 5 µM concentration. According to the results of cell cycle, radiation was performed. CCK-8 test was used to test the cell proliferation. Then we performed the same study in vivo. Total of 40 male nude mice were randomly divided into four groups as follows: SKF96365, radio, combined radio-SKF96365 and control. In SKF96365 group, 20 mg/kg 5 µM SKF96365 was injected into the abdominal cavity of the nude mice at day 5-11. In radiation group, the nude mice received radiotherapy 2 Gy per day at day 7-11. In combined radio-SKF96365 group, 20 mg/kg 5 µM SKF96365 was injected into the abdominal cavity of the nude mice at day 5-11 and 2 Gy radiotherapy was delivered to the tumor site at day 7-11. In control group, nude mice were injected saline into the abdominal cavity at day 5-11. General states of health were observed, the tumor size in volume was measured with calipers two times every week. Six weeks after seeding, mice were sacrificed by neck-break. The tumor size was measured in volume with caliper and in weigh with scale. Treatment with SKF96365 substantially increased the percentage of Eca109 cells in the G2/M phase and reduced that in G0/G1 phase in a time-dependent manner. Most of the cells (85.26%), 24 h after SKF96365 treatment were arrested in the G2/M phase. CCK-8 test showed that Eca109 ESCC cells received both SKF96365 and radiation showed the worst ability of cell proliferation. The same result was obtained in vivo. Nude mice received combined radio-SKF96365 showed the smallest tumor size and volume. TRPC6 plays an important role in development of esophageal cancer, and SKF96365 may increase the sensitivity of radiotherapy. TRPC6 may become a new radiotherapy target in esophageal cancer.

Effect of lentivirus-mediated expression of RNF2 gene on the proliferation and migration of esophageal carcinoma cells following X-ray radiotherapy

Objective To examine the effect of X-ray radiotherapy on cell proliferation, migration, apoptosis, and cell cycle of human esophageal carcinoma ECA-109 cells following RNA interference (RNAi)-mediated downregulation of RNF2 gene expression. Methods The level of RNF2 mRNA expression in the human esophageal carcinoma cell line ECA-109 was determined using RT-PCR. Cell proliferation of ECA-109 was measured by MTT assay, and the changes in RNF2 protein expression in ECA-109-R cells were determined using Western blot. The changes in cell cycle and cell apoptosis at different time points following radiation were analyzed by flow cytometry, and the effect of transduction on cell migration was examined using Transwell migration assay. Data were subjected to an analysis of variance with repeated measurement design. Results The mean mRNA and protein levels of RNF2 in ECA-109 cells were significantly increased in a dose-dependent manner in the radiation group than in the control group (P 0.05). The Transwell migration assay showed that the number of migrating cells following 3.5 h of radiation was significantly lower in the ECA-109-R group than in the ECA-109 and ECA-109-N groups (P<0.01). The percentage of G2/M phase cells in each group was significantly lower following 6 Gy radiation compared to that in the corresponding untreated group (P<0.01), and the percentage of G2/M phase cells was significantly lower in the ECA-109-R group than in the ECA-109 and ECA-109-N groups (P<0.05). Furthermore, cell apoptosis following radiation was also significantly higher in the ECA-109-R group than in the ECA-109 and ECA-109-N groups (P<0.01). Conclusions RNAi-mediated downregulation of RNF2 expression in esophageal carcinoma cells can reduce cell proliferation and cell migration, rescue post-radiation G2/M cell cycle arrest, promote cell apoptosis, and increase radiosensitivity. Key words: RNF2 gene; Cell proliferation; Apoptosis; Cell cycle; Esophageal carcinoma cell line

Emodin inhibits proliferation and invasion, and induces apoptosis in human esophageal cancer cell line ECA109

Purpose: To determine the anticancer effects of emodin in human esophageal carcinoma cell line ECA109. Methods: Cell viability was determined by MTT assay, while cell invasion and apoptosis were measured by Transwell assay and flow cytometry, respectively. Expression levels of MMP-2, Bax, Bcl-2 and caspase-3 proteins were determined by Western blot. Results: Flow cytometry data showed that the proportion of apoptotic cells was increased by emodin treatment. Apoptotic rates produced by 10, 20 and 50 μM emodin were 13.9 ± 3.8, 25.6 ± 6.2 and 39.8 ± 7.7 %, respectively. Transwell assay data revealed concentration-dependent suppression of the invasive rate of ECA109 cells by emodin (10, 20 and 50 μM) was 30.0 ± 4.5, 56.0 ± 6.8 and 69.0 ± 8.1 %, respectively. Furthermore, emodin treatment inhibited expressions of MMP-2 and Bcl-2 proteins, but induced the expression of Bax and caspase-3, when compared with control groups. Conclusion: These results suggest that emodin inhibits cell proliferation and cell invasion, but induces cell apoptosis in human esophageal cancer cell line ECA109. Thus, emodin is a potential candidate for development of an effective chemotherapeutic agent against esophageal cancer. Keywords: Emodin, Esophageal Cancer, Apoptosis, Cell invasion, Bax, Caspase-3

A novel 5-fluorouracil-resistant human esophageal squamous cell carcinoma cell line Eca-109/5-FU with significant drug resistance-related characteristics.

5-Fluorouracil (5-FU) is used for the clinical treatment of esophageal squamous cell carcinomas (ESCCs), yet it also induces chemoresistant cancer cells during treatment, which leads to the failure of the therapy. To further explore the resistance mechanism of 5-FU in ESCC, we established the 5-FU-resistant ESCC cell line Eca-109/5-FU, which was prepared by the stepwise exposure to increasing 5-FU concentrations. MTT assay and nude mouse xenograft models were used to test the drug resistance and proliferation of Eca-109 and Eca-109/5-FU cells invitro and invivo. Apoptosis and cell cycle distribution were determined using flow cytometry. Drug resistance-related proteins were detected by western blotting. Metabolomic profiles were obtained from nuclear magnetic resonance (NMR) tests. In regards to Eca-109/5-FU, the decreased susceptibility to 5-FU was determined invitro and invivo with slower rate of proliferation. Drug resistance-related proteins (multidrug resistance-associated protein1 and ATP-binding cassette superfamilyG member 2), epithelial-to-mesenchymal transition (EMT)-related proteins (E-cadherin and vimentin) and cancer stem cell-related proteins (prominin-1 and hyaluronate receptor) exhibited significant differences between the two cell lines. The 5-FU-resistant cell line Eca-109/5-FU achieved the ability to tolerate 5-FU, which may depend on significant drug resistance-related characteristics, such as EMT and cancer stem cell-like properties. The metabolism of Eca-109/5-FU was altered, and more than 15 metabolites was found to contribute to the difference in the metabolite profile, such as lactate, glutamate, taurine, glutamine, proline, aspartate, methanol, cystine, glycine and uracil. Our results identified that the resistant cell line Eca-109/5-FU showed quite different characteristics compared with the parental Eca-109 cells. The Eca-109/5-FU cell line provides an experimental model for further steps to select chemotherapeutic sensitizers.

Expression of miR-944 in esophageal squamous cell carcinoma and its role in cell proliferation and invasion in human esophageal carcinoma cell line Eca109

Expression of miR-944 in esophageal squamous cell carcinoma and its role in cell proliferation and invasion in human esophageal carcinoma cell line Eca109

Bortezomib sensitizes esophageal squamous cancer cells to radiotherapy by suppressing the expression of HIF-1α and apoptosis proteins.

Radiation therapy is a typical treatment for esophageal squamous cell carcinoma (ESCC), especially middle and upper segment esophagus, and inoperable patients. However, how to promote radiation sensitivity in radio-resistant cancer cells is a conundrum. Here, our study investigated the radiosensitizing effect of bortezomib, a specific and reversible dipeptide boronic acid analog, in ESCC cells. Human esophageal squamous carcinoma cell lines Eca109 and TE-13 were exposed to hypoxia and/or ionizing radiation (IR) with or without treatment of bortezomib. Cell proliferation assay was performed with CCK8. Cell apoptosis and cell cycle assay were performed with flow cytometry. The radiosensitization effect of was assessed by clonogenic survival and progression of tumor xenograft. The expression of HIF-1α, VEGF, and apoptosis proteins was evaluated by Western blot. Radiation-induced DNA double strand break and homologous recombination repair were assessed by immunofluorescence. Our results show that bortezomib efficiently radiosensitizes ESCC cells by decreasing the expression of HIF- 1α and VEGF, inducing apoptosis by activating caspase, and delaying DNA damage repair after radiation.

Herpes simplex virus type 1 VP22-mediated intercellular delivery of PTEN increases the antitumor activity of PTEN in esophageal squamous cell carcinoma cells in vitro and in vivo

In the past decade, studies have revealed that the phosphatase and tensin homolog (PTEN) protein, a tumor suppressor, comprises a potential biological marker and therapeutic target for esophageal squamous cell carcinoma (ESCC). As such, the delivery of the PTEN gene represents a powerful strategy for ESCC therapy. The tegument protein VP22 of herpes simplex virus type 1 (HSV-1) has been reported to act as a transporter of heterologous proteins across the host cell membrane, thereby enhancing the biological functions of these proteins. In the present study, the intercellular delivery and antitumor activity of the fusion protein PTEN-VP22 were examined in the esophageal squamous cell carcinoma cell line Eca109 both in vitro and in vivo. VP22-mediated PTEN intercellular delivery was confirmed in the Eca109 cells by western blot analysis and by quantitation of immunofluorescence. VP22 alone did not exert antiproliferative effects or induce cell cycle arrest, induction of apoptosis, blockage of the Akt and focal adhesion kinase (FAK) pathways, tumor growth inhibition, or antiangiogenic effects in Eca109 cells. However, compared with PTEN alone, PTEN-VP22 exerted significantly higher antiproliferative effects and induced cell cycle arrest at G1 stage, apoptosis and antiangiogenic effects in Eca109 cells. Together, our findings demonstrate that VP22 alone does not exert antitumor activity directly; however, this protein mediates the intercellular delivery of PTEN and thereby increases its intracellular concentration to achieve a therapeutic steady state, leading to an overall increase in the antitumor activity of PTEN. This study provides further experimental data to confirm the potential of VP22-based intercellular delivery strategies for enhancing the efficacy of gene therapy for cancer treatment.