Elevated HNF1A expression promotes radiation-resistance via driving PI3K/AKT signaling pathway in esophageal squamous cell carcinoma cells.

Purpose: Radiotherapy is a major modality for treatment of local advanced esophageal squamous cell carcinoma (ESCC). Hepatocyte nuclear factor 1-alpha (HNF1A) is involved in regulation of tumor cell proliferation, apoptosis, cycle distribution, invasion metastasis and chemical resistance. The aim of this study was to investigate the effect of HNF1A on radiosensitivity of ESCC cells. Methods: In our study, HNF1A expression was verified from GEPIA in multiple types of cancer. The prognostic value of HNF1A in ESCC was obtained by TCGA database. In addition, the expression of HNF1A in ESCC cell lines was verified by western blot. Subsequently, lentiviruses were used to construct HNF1A overexpressed cell lines TE1 and KYSE150.Then, the roles of HNF1A on cell proliferation, invasion, apoptosis, cell cycle distribution and radiosensitivity were verified. Furthermore, the relationship between HNF1A and γH2AX were determined by western blot and immunofluorescence. We also detected the expression changes of key factors in PI3K/AKT pathway after overexpression of HNF1A. Results: The results showed that the overexpression of HNF1A promoted cell proliferation and invasion with or without irradiation (IR), and potently radiation-resistance ESCC cells with a sensitization enhancement ratio (SER) of 0.76 and 0.87. In addition, HNF1A regulated Cyclin D1 and CDK4 proteins to promote the transition from radiation-induced G0/G1 phase arrest to S phase, and coordinated BAX and BCL2 proteins to reduce the occurrence of radiation-induced apoptosis. It was worth noting that HNF1A might be involved in radiation-induced DNA damage repair by regulating γH2AX though PI3K/AKT signal pathway. Conclusion: Our study preliminarily suggested that HNF1A was associated with the progression and radiosensitivity of ESCC cells, and it might reduce the radiosensitivity of ESCC cells by promoting cell proliferation, releasing G0/G1 phase arrest, reducing apoptosis, and regulating the expression of γH2AX protein though driving PI3K/AKT signal pathway.

Knockdown of FAM83D Enhances Radiosensitivity in Coordination with Irradiation by Inhibiting EMT via the Akt/GSK-3ß/Snail Signaling Pathway in Human Esophageal Cancer Cells.

PURPOSE: To explore the effects of FAM83D on the proliferation, invasion and radiosensitivity of human esophageal cancer cells and to elucidate the mechanism involved in the regulation of the growth and metastasis of esophageal cancer cells. METHODS AND MATERIALS: This study included sixty-nine patients with esophageal cancer. The expression levels of FAM83D in the esophageal cancer tissues and paracarcinoma tissues of the sixty-nine patients were measured. We also examined FAM83D expression in five cell lines. We analyzed the effects of FAM83D on the proliferation, invasion and radiosensitivity of human esophageal cancer cells via MTS, Transwell, and colony formation assays. The effect of FAM83D knockdown on cell apoptosis was assayed by flow cytometry. In addition, we also examined changes in the expression of metastasis-related molecules at the protein and mRNA levels by qRT-PCR and Western blotting after silencing FAM83D expression, and we detected the expression of PI3K/Akt signaling-related proteins by Western blotting. RESULTS: The results demonstrated that the expression of FAM83D was obviously higher in esophageal cancer tissues and cell lines than that in human adjacent normal tissues and normal esophageal epithelial cell lines. FAM83D overexpression was positively associated with tumor size, tumor-node-metastasis (TNM) stage, T classification, N classification, distant metastasis and relapse and was negatively associated with patient survival rates. FAM83D shRNA transfection suppressed its expression. Compared to that in the control group, the proliferation of tumor cells in the FAM83D shRNA group was hindered after exposure to radiation in vitro and in vivo; in addition, FAM83D knockdown inhibited cell invasion, induced apoptosis and regulated apoptosis-related protein expression. Moreover, the radiosensitivity of esophageal cancer cells was increased after depletion of FAM83D. In addition, FAM83D silencing was associated with the reversion of EMT, as reflected by an increase in the epithelial marker E-cadherin and a decrease in the mesenchymal markers N-cadherin and vimentin. Further study showed that FAM83D depletion suppressed the signaling pathway involving p-Akt, p-GSK-3ß and Snail. CONCLUSION: The results reveal that FAM83D may be a potential therapeutic target for esophageal squamous cell carcinoma (ESCC) and that lower expression of FAM83D in coordination with irradiation promotes the radiosensitization of ESCC by inducing EMT through the Akt/GSK-3ß/Snail signaling pathway.

Association between RNF2+P-AKT expression in pretreatment biopsy specimens, and poor survival following radiotherapy in patients with esophageal squamous cell carcinoma.

The protein expression levels of Ring finger protein 2 (RNF2) and phosphor-protein kinase B (P-AKT) were determined in esophageal squamous cell carcinoma (ESCC) tissues, and the association between patient clinicopathological characteristics and survival time following definitive intensity-modulated radiotherapy was assessed. Cancerous biopsy tissues were collected from patients with ESCC at The Fourth Affiliated Hospital of Hebei Medical University between January 2010 and December 2013. Of these 99 cases, 83 were used to analyze the protein expression level of RNF2 (89.2% positive), 85 for P-AKT (65.9% positive) and 80 for RNF2+P-AKT protein expression levels (62.5% both positive). The expression levels of RNF2 protein in ESCC were associated with tumor volume (P=0.024), whilst those of P-AKT and RNF2+PAKT were associated with sex (P=0.041 and P=0.003, respectively). There were no significant differences in overall survival (OS) or progression-free survival (PFS) rate between the RNF2- and the RNF2+-+++ groups (P=0.134 and P=0.366, respectively), or between the P-AKT- group and P-AKT+-+++ group (P=0.468; P=0.580, respectively). The 1-, 3- and 5-year OS rates were 68.0, 28.0, and 20.0%, and 86.7, 53.3, and 31.1%, in the RNF2/P-AKT+ group and Other group, respectively (χ2=4.205; P=0.040). Multivariate analysis revealed that age, T stage and RNF2+P-AKT expression were independent prognostic factors for ESCC (P=0.010, P=0.008 and P=0.010, respectively). The expression of RNF2+P-AKT combined was an independent prognostic factor affecting survival rate, and therefore presents a potential prognostic indicator for patients with ESCC, treated with definitive radiotherapy.

Radiosensitization of esophageal carcinoma cells by knockdown of HMGB1 expression.

Radiotherapy (RT) is a traditional and important treatment for carcinoma of the esophagus along with surgery and chemotherapy. High mobility group box 1 (HMGB1) plays a crucial part in inhibiting the apoptosis of cancer cells after irradiation treatment. The present study, was designed to analyze the function of HMGB1 in esophageal cancer progression and elucidate the effects of HMGB1 on the radiosensitivity of human esophageal cancer cell lines. In the present study, an immunohistochemical evaluation of HMGB1 was performed on 77 biopsies, and the results revealed that HMGB1 overexpression was positively correlated with gross tumor volume (GTV), tumor­node­metastasis (TNM) stage, T classification, distant metastasis, and relapse and negatively correlated with patient survival rates, suggesting that HMGB1 acts as a key factor in the development of esophageal cancer. An shRNA targeting HMGB1 was designed for the knockdown of HMGB1 in ECA109 and TE13 cells, and the transfection efficiency of the shRNA was assessed using quantitative real­time reverse transcription polymerase chain reaction and western blot analysis. CCK­8 and clonogenic assays were used to analyze the effect of HMGB1 on the proliferation and radiosensitivity, respectively, of esophageal cancer cells in vitro. The influence of HMGB1 on radiation­induced changes in the migration, invasion, and cell cycle as well as apoptosis of tumor cells was examined by wound­healing and Transwell assays and flow cytometry, respectively. In addition, xenograft tumor models were constructed to observe the effect of HMGB1 on tumor growth in vivo. The results of the study in vitro revealed that the proliferation of the HMGB1­shRNA group decreased after irradiation, and the radiation treatment reduced the tumor volume of the xenograft model which was more marked in HMGB1­shRNA group. Moreover, HMGB1 was involved in the phosphorylation of H2AX after irradiation, and HMGB1 knockdown blocked the cell cycle in the G0/G1 phase and increased apoptosis. HMGB1 deficiency was also correlated with the upregulation of p16, Bax and caspase­9 and the downregulation of MMP­2, MMP­9, cyclin D1, CDK4, γH2AX and Bcl­2. These data indicated that the overexpression of HMGB1 prior to treatment was correlated with poor clinical outcome in esophageal carcinoma and that knockdown HMGB1 expression in human esophageal cancer cell lines increased their radiosensitivity by allowing the induction of apoptosis and G0/G1 arrest after exposure to radiation.

The clinical significance of Mda-7/IL-24 and C-myb expression in tumor tissues of patients with diffuse large B cell lymphoma.

Diffuse large B cell lymphoma (DLBCL) is the most common type of non-Hodgkin's lymphoma in adults. Mda-7/IL-24 had been identified as a differentiation inducer of B phenotype lymphoma cells. Previous studies have revealed that knockdown of C-myb also leads to the terminal differentiation of B cell lymphoma. The aim of the present study was to investigate the association between the expression of Mda-7/IL-24 and C-myb, and their prognostic significance for DLBCL patients. The tumor tissues were collected from 72 cases of DLBCL patients and detected with reverse transcription-quantitative polymerase chain reaction, western blotting and immunohistochemistry assays. The results showed that, the expression of Mda-7/IL-24 mRNA and protein was lower while the expression of C-myb was higher in DLBCL tissues, compared with the specimens of normal lymph node tissues. Furthermore, C-myb expression was negatively correlated with Mda-7/IL-24 expression at mRNA and protein levels in DLBCL tissues. The expression of Mda-7/IL-24 and C-myb in DLBCL tissues was associated with some clinicopathological parameters such as clinical stage, infiltration in bone marrow, Ki67 expression level in the tumor tissues and overall survival rates. These results indicated that low expression of Mda-7/IL-24, along with high expression of C-myb, are predictor for poor prognosis of DLBCL patients, suggesting that Mda-7/IL-24 and C-myb may be potential targets for clinical treatment of DLBCL.

Celecoxib enhances sensitivity to chemotherapy drugs of T-cell lymphoma.

Celecoxib is a newly-identified nonsteroidal anti-inflammatory drug, which has been used to treat fever in clinical practice. Celecoxib has been demonstrated to suppress the viability of various human tumor cells. However, the effect of celecoxib on response of T-cell lymphoma to chemotherapy agents remains unclear. The aim of the present study was to investigate the effect of celecoxib on chemosensitivity of human T-cell lymphoma, and to address the underlying mechanism of action. The cytotoxicity of CDDP, epirubicin and VCR on Jurkat and Hut-78 cells treated with celecoxib was assessed by MTT assay, and the half-maximal inhibitory concentration (IC50) value was calculated by Origin 75 software. The effect of celecoxib on apoptosis and intracellular concentration of Rhodamine-123 in Jurkat and Hut-78 cells was analyzed by flow cytometry. The expression of transcription factor p65 (p65), B-cell lymphoma 2 (Bcl-2), Bcl-2-associated X protein (Bax), multidrug resistance 1 (MDR1) and multidrug resistance-associated protein 1 (MRP1) at mRNA and protein levels were detected by reverse transcription quantitative polymerase chain reaction and western blotting, respectively. Proliferation suppression rates and apoptosis levels were significantly increased in Jurkat and Hut-78 cells combined with celecoxib compared with those without celecoxib, when treated with CDDP, epirubicin and VCR. The IC50 values of the chemotherapy agents were lower in Jurkat and Hut-78 cells treated with celecoxib compared with those that were not. The apoptosis level, expression of Bax and the intracellular concentration of Rhodamine-123 were increased, whereas the expression of p65, Bcl-2, MDR1 and MRP1 were decreased, in celecoxib-treated Jurkat and Hut-78 cells compared with those without celecoxib treatment. These results indicated that celecoxib may enhance the sensitivity of T-cell lymphoma to chemotherapy drugs by inhibiting the expression of multidrug resistance (MDR)-associated proteins via downregulating the activity of the nuclear factor-κB signaling pathway, suggesting that celecoxib may improve the curative effect of chemotherapy drugs in T-cell lymphoma.

Low expression of Mda-7/IL-24 and high expression of C-myb in tumour tissues are predictors of poor prognosis for Burkitt lymphoma patients.

Objectives Burkitt lymphoma is one of the most common types of haematopoietic malignancy in children and adolescents. Mda-7/IL-24 had been identified as a differentiation inducer of Burkitt lymphoma cells. Previous studies have revealed that knockdown of C-myb can also lead to the terminal differentiation of Burkitt lymphoma cells. The aim of the present study was to investigate the correlation between the expression of Mda-7/IL-24 and C-myb, as well as their prognostic significance, for Burkitt lymphoma patients. Methods The tumour tissues were collected from 59 cases of Burkitt lymphoma patients and detected with Western blotting and immunohistochemistry. Results The results showed that the expression of Mda-7/IL-24 was lower, whereas the expression of C-myb was higher in Burkitt lymphoma tissues compared to specimens of normal lymph node tissues. Furthermore, C-myb expression was negatively correlated with Mda-7/IL-24 expression at the protein level in Burkitt lymphoma tissues and cell lines. Both the expression of Mda-7/IL-24 and C-myb in Burkitt lymphoma tissues was associated with some clinicopathological parameters, such as clinical stage, infiltration in the bone marrow, Ki67 and overall survival rates. Conclusion These results indicated that low expression of Mda-7/IL-24 along with high expression of C-myb are predictors for poor prognosis of Burkitt lymphoma patients; this outcome suggests that Mda-7/IL-24 and C-myb might be potential targets for clinical treatment of Burkitt lymphoma. ABBREVIATIONS: Mda-7/IL-24: melanoma differentiation associated gene7/interleukin 24; FCM: flow cytometry; Ecog: Eastern Cooperative Oncology Group; IPI: International lymphoma prognosis index.

BMI-1 suppression increases the radiosensitivity of oesophageal carcinoma via the PI3K/Akt signaling pathway.

B-cell­specific Moloney murine leukaemia virus integration site-1 (BMI-1) contributes to the growth of tumour cells post-irradiation (IR). The aim of the present study was to characterize the effects of BMI-1 on cell viability, radiosensitivity and its mechanisms of action in oesophageal squamous cell cancer (ESCC). Western blotting and immunohistochemistry were employed to evaluate the protein expression of BMI-1 in ESCC cells and specimens, respectively. Additionally, the protein expression levels of BMI-1, H2AK119ub and γH2AX in ESCC cells were detected following different doses of IR and at different times after IR. The protein expression levels of MDC1 and 53BP1 were also measured. Flow cytometry and MTT assays were used to determine cell cycle progression, apoptosis and cell viability. The phosphatidylinositol 3-kinase inhibitor LY294002 and the agonist IGF-1 were employed to suppress or induce the phosphorylation of Akt to determine whether BMI-1 induces radioresistance in ESCC cells via activation of the PI3K/Akt pathway. The expression of BMI-1 was higher in ESCC tissues and cells compared with that in normal oesophageal tissues and cells. In addition, BMI-1 was positively related to tumour size and lymph node metastases and negatively to the overall survival of ESCC patients. IR induced the expression of BMI-1, H2AK119ub and γH2AX in a dose- and time-dependent manner. BMI-1 knockdown lowered the expression of γH2AX, MDC1 and 53BP1, suppressed cell viability and increased radiosensitivity. G2/M phase arrest was eliminated; this was followed by an increased proportion of cells entering the G0/G1 phase after IR and BMI-1 knockdown via the upregulation of P16 and downregulation of cyclin D2 and cyclin-dependent kinase-4. Moreover, BMI-1 knockdown increased cell apoptosis, downregulated MCL-1 and p-Akt and upregulated Bax. Additionally, the inhibitory effect of the downregulation of p-Akt by LY294002 on tumour cell viability was identical to that of BMI-1 knockdown, while the kinase agonist IGF-1 reversed the effects of BMI-1 knockdown on cell viability and radiosensitivity. Taken together, BMI-1 knockdown induces radiosensitivity in ESCC and significantly inhibits cell viability, which may contribute to an increased proportion of cells in the G0/G1 phase and cell apoptosis via suppression of the PI3K/Akt signalling pathway.

Mda­7/IL­24 induces the differentiation of B cell lymphoma via activation of the P38 mitogen activated protein kinase signaling pathway.

Interleukin 24 (IL­24) is a unique cytokine encoded by the melanoma differentiation associated gene­7 (Mda­7), and was first discovered inhuman melanoma cells. Exogenous Mda­7/IL­24 has been shown to inhibit the proliferation and invasion of a broad spectrum of human cancer cells, but its effect on the differentiation of B cell lymphoma is not yet clear. To the best of our knowledge, the present study demonstrated for the first time that overexpressing Mda­7/IL­24 can induce differentiation in human B cell lymphomacells, and the underlying mechanism was investigated. The proliferation of stable Mda­7/IL­24 overexpressing Raji and Daudi cells was assessed by the MTS method. The immunophenotype, apoptosis level and cell cycle distribution of Raji and Daudi cells were analyzed by flow cytometry. The expression of PR domain zinc finger protein 1 (Blimp1) and B­cell lymphoma 6 (Bcl6) were analyzed by western blotting. Additionally, western blotting assay was also performed to study the effect of Mda­7/IL­24 on the activity of the P38 mitogen activated protein kinase (MAPK) signaling pathway in Raji and Daudi cells. Proliferation of Raji and Daudi cells overexpressing Mda­7/IL­24 was inhibited significantly, compared with those of parent cells and cells transfected with the empty vector alone. Apoptosis was not involved in the proliferation inhibition, while the cell cycle was arrested in G1 phase in the Raji and Daudi cells overexpressing Mda­7/IL­24. Overexpressing Mda­7/IL­24 resulted in a significantly decreased expression of cluster of differentiation (CD)10, and increased expression of CD45 and CD138 in the cell surface of Raji and Daudi cells. The expression of Blimp1 was upregulated, while the levels of Bcl6 protein was downregulated, in Raji and Daudi cells overexpressing Mda­7/IL­24. Furthermore, the activities of the P38 MAPK signaling pathway in lymphoma cells were upregulated. These results indicated that Mda­7/IL­24 could induce terminal differentiation of B lymphoma cells by regulating the expression of Blimp1 and Bcl6 via altering the P38 MAPK signaling pathway, suggesting that Mda­7/IL­24 may therefore be a potential differentiation therapeutic agent to be applied in clinical treatment of B cell lymphoma.

p-Hydroxylcinnamaldehyde induces the differentiation of oesophageal carcinoma cells via the cAMP-RhoA-MAPK signalling pathway.

p-Hydroxylcinnamaldehyde (CMSP) has been identified as an inhibitor of the growth of various cancer cells. However, its function in oesophageal squamous cell carcinoma (ESCC) and the underlying mechanism remain unclear. The aim of the present study was to characterize the differentiation effects of CMSP, as well as its mechanism in the differentiation of ESCC Kyse30 and TE-13 cells. The function of CMSP in the viability, colony formation, migration and invasion of Kyse30 and TE-13 cells was determined by MTS, colony-formation, wound healing and transwell assays. Western blotting and pull-down assays were used to investigate the effect of CMSP on the expression level of malignant markers of ESCC, as well as the activity of MAPKs, RhoA and GTP-RhoA in Kyse30 and TE-13 cells. We found that CMSP could inhibit proliferation and migration and induce Kyse30 and TE-13 cell differentiation, characterized by dendrite-like outgrowth, decreased expression of tumour-associated antigens, as well as the decreased expression of malignant markers. Furthermore, increased cAMP, p-P38 and decreased activities of ERK, JNK and GTP-RhoA, were detected after treatment with CMSP. These results indicated that CMSP induced the differentiation of Kyse30 and TE-13 cells through mediating the cAMP-RhoA-MAPK axis, which might provide new potential strategies for ESCC treatment.

TIM-3 promotes the metastasis of esophageal squamous cell carcinoma by targeting epithelial-mesenchymal transition via the Akt/GSK-3ß/Snail signaling pathway.

T-cell immunoglobulin and mucin domain-con-taining protein-3 (TIM-3), a negative regulator of antitumor immune response, has been demonstrated to be involved in the onset and progression of several types of malignancies. The present study aimed to determine whether and how TIM­3 plays such a role in esophageal squamous cell carcinoma (ESCC). TIM-3 expression was analyzed by immunohistochemistry and real­time fluorescence quantitative PCR (qRT­PCR) in ESCC and matched adjacent normal tissues. Functional experiments in vitro were performed to elucidate the effect of TIM­3 knockdown on the proliferation, apoptosis, migration, invasion and epithelial-mesenchymal transition (EMT) in Eca109 and TE­1 cell lines. Our data revealed that TIM­3 expression was significantly elevated at both the mRNA and protein levels in ESCC tissues compared with the levels in the matched adjacent normal tissues (both P<0.001). TIM­3 expression was significantly associated with lymph node metastasis (P=0.008), tumor­node­metastasis (TNM) stage (P=0.042) and depth of tumor invasion (P=0.042). In addition, we observed a strong correlation between high TIM­3 expression and a worse overall survival of ESCC patients (P=0.001). Functional study demonstrated that TIM­3 knockdown markedly inhibited proliferation, migration and invasion of ESCC cell lines without affecting apoptosis. In addition, TIM­3 depletion was associated with downregulation of matrix metalloproteinase (MMP)-9 and upregulation of tissue inhibitor of metalloproteinase (TIMP)-1, and with reversion of EMT, as reflected by higher levels of the epithelial marker E­cadherin and lower levels of the mesenchymal markers N­cadherin and vimentin. Further study found that TIM­3 depletion suppressed the signaling pathway involving p­Akt, p­GSK­3ß and Snail. Taken together, these results suggest that TIM­3 is a novel therapeutic target and prognostic biomarker for ESCC and promotes metastasis of ESCC by inducing EMT via, at least partially, the Akt/GSK-3ß/Snail signaling pathway.

Radiosensitization of esophageal carcinoma cells by the silencing of BMI-1.

Radiotherapy (RT) has been widely used to treat cancer patients, particularly esophageal cancer patients. B-cell-specific Moloney murine leukemia virus integration site-1 (BMI-1) plays an important role in promoting the growth of cancer cells after exposure to irradiation. The present study aimed to characterize the effects of BMI-1 on the proliferation and invasion of cancer cells, as well as the mechanism involved in the regulation of the growth of esophageal cancer ECA109 and TE13 cells. The expression levels of the BMI-1 gene and protein in esophageal cancer ECA109 and TE13 cells were determined by quantitative PCR and western blotting after transfection. Co-immunoprecipitation (Co-IP) assay was employed to detect the interaction of BMI-1 with r-H2AX and H2AK119ub. We used flow cytometry to analyze the cell cycle distribution and apoptosis of transfected cells after irradiation or not, and examined cellular growth and invasion in vitro by MTS and Transwell assays. The results revealed that shRNA targeting the BMI-1 gene and protein downregulated BMI-1 expression after transfection for 24 h. The proliferation and invasion of tumor cells in the BMI-1­shRNA group were suppressed after RT. In addition, the interaction of BMI-1, H2AK119ub and r-H2AX was increased after exposure to IR, followed by an increased apoptosis rate and decreased percentage of cells arrested at the G2/M phase after irradiation and silencing of BMI-1 by shRNA. Knockdown of BMI-1 expression decreased the phosphorylation of H2AX, upregulated p16, and induced the radiosensitivity of esophageal cancer ECA109 and TE13 cells in vitro and significantly inhibited the growth and invasion of tumor cells. The mechanisms were found to be abrogation of cell cycle arrest at the G2/M stage and promotion of apoptosis.

Radiosensitization of esophageal carcinoma cells by knockdown of RNF2 expression.

Radiotherapy has been widely used for the treatment of cancer patients, especially for esophageal cancer patients. Ring finger protein 2 (RNF2) plays an important role in promoting the growth of cancer cells after exposure to irradiation. The present study aims to characterize the proliferative effects of RNF2 on cancer cells, and its mechanisms on the growth of esophageal cancer cells. We demonstrate that expression of RNF2 was markedly upregulated in esophageal cancer cell lines and surgically resected cancer specimens. In addition, RNF2 expression level is positively correlated with the presence of tumor size, lymph node metastases and negatively correlated with patient survival rates, suggesting that it plays an important role in the progression of esophageal cancer. Furthermore, the expression of RNF2 at both mRNA and protein levels in esophageal cancer ECA109 and TE13 cells was detected by real-time PCR and western blot assay after shRNA targeting RNF2. Co-immunoprecipitation (Co-IP) assay and western blot analysis were employed to detect the interaction between RNF2 and r-H2AX, H2AK119ub, and the expression of proteins associated with cell cycle and apoptosis, respectively. We used flow cytometry assay to analyze cell cycle and apoptosis of transfected cells, and further examined cellular growth in vitro and in vivo. shRNA targeting RNF2 gene and protein downregulated RNF2 expression after transfection for 24 h. The proliferation of tumor cells in RNF2-shRNA group was suppressed after radiotherapy. In addition, the interaction of RNF2, H2AK119ub, r-H2AX was increased after exposure to IR, followed by increasing apoptosis rates and inducing the arrest at G0/G1 phase after irradiation and shRNA targeting RNF2. Expression of the short-hairpin RNA is also correlated with the upregulation of p16 and Bax, and the downregulation of cyclin D2, cyclin-dependent kinase (CDK)-4, H2AX and Bcl-2. RNF2 gene knockdown induces radiosensitivity of esophageal cancer cells in vitro and significantly inhibits the growth of tumor cells. The mechanisms include inducing the cell cycle arrest at G0/G1 phase and promoting apoptosis.

Mda-7/IL-24 enhances sensitivity of B cell lymphoma to chemotherapy drugs.

Interleukin-24 (IL-24) is a cytokine encoded by a tumor suppressor gene of the IL-10 family, also known as the melanoma differentiation associated gene-7 (Mda-7) and first discovered in human melanoma cells. Mda-7/IL-24 has been shown to inhibit the proliferation of various human tumor cell lines, but its effect on the sensitivity of B cell lymphoma to chemotherapy agents is not yet clear. The present study investigated the effects of Mda-7/IL-24 overexpression on the sensitivity of human B cell lymphoma cells to chemotherapy, as well as its mechanism of action. The sensitivity of stable Mda-7/IL-24 overexpressing Raji and Daudi cells to cis-diamminedichloroplatinum (CDDP), epirubicin and vinblastine (VCR) were assessed by the MTS method, and the IC50 value calculated. Cell apoptosis and the intracellular accumulation of Rhodamine-123 were assayed by flow cytometry. The expression of multidrug resistance gene 1 (MDR1), B-cell-specific Moloney murine leukemia virus insertion site 1 (BMI1), topoisomerase II (Topo II) and multidrug resistance-related protein 1 (MRP1) mRNA and protein were analyzed by reverse transcription quantitative polymerase chain reaction (RT-qPCR) and western blotting, respectively. In addition, western blot analysis was also used to investigate the effect of Mda-7/IL-24 on activity of GTP-RhoA-ERK signaling pathway in Raji and Daudi cells. Growth inhibition and apoptosis rates of Mda-7/IL-24 overexpressing Raji and Daudi cells were higher than those of non-transfected cells and cells transfected with vector alone when treated with CDDP, epirubicin and VCR. The IC50 values of CDDP, epirubicin and VCR were lower for Mda-7/IL-24-overexpressing Raji and Daudi cells than for non-transfected cells and cells transfected with empty vector. Intracellular accumulation of Rhodamine-123 and the expression of Topo II were higher, while the levels of MDR1, BMI and MRP1 mRNA and protein were lower, in Mda-7/IL-24 overexpressing Raji and Daudi cells. Furthermore, the activities of GTP-RhoA-ERK signaling pathway in Raji and Daudi cells were suppressed. These results indicated that Mda-7/IL-24 enhanced the sensitivity of B lymphoma cells to chemotherapy agents by altering the expression of multidrug-resistance genes via downregulating GTP-RhoA-ERK signaling pathway, suggesting that treatment of B cell lymphomas with Mda-7/IL-24 could avoid MDR.

[Effect of Tanreqing injection on immune activity of peripheral blood lymphocytes of patients with lung cancer].

To investigate the effect of Tanreqing injection on immune activity of peripheral blood lymphocytes of patients with lung cancer. The peripheral blood lymphocytes of patients with lung cancer and healthy persons were separated by the density gradient centrifugation method for subsequent experiments, with those from healthy persons as the positive control. The effect of Tanreqing injection on stimulating the proliferation of lymphocytes with phytohemagglutinin (PHA) was determined by MTT method. The effect of Tanreqing injection on the lymphocyte secretions of IFN-γ and TNF-α and the subset ratio of lymphocytes cultured separately or with Tanreqing injection of different concentrations were examined by ELISA and flow cytometry (FCM) respectively. In addition, the LDH release assay was used to detect the cytotoxicity of cytotoxic T cells (CTL) and natural killer cells (NK). According to the findings, all of immunological indexes of lymphocytes from patients with lung cancer were weaker than that of healthy persons, but with the obvious increases in proliferation activity and IFN-γ and TNF-α secretions of lymphocytes co-cultured with Tanreqing Injection (P < 0.05). Among lymphocyte subsets co-cultured with Tanreqing Injection, CD3+, CD3+ CD4+ and CD3- CD16 + 56+ cell ratios notably increased, whereas CD4+ CD25+ Treg cell ratio obviously decreased (P < 0.05). In the meantime, Tanreqing injection can markedly promote the cytotoxicities of CTL and NK (P < 0.05). In conclusion, Tanreqing injection shows a significant effect in promoting the immune activity of lymphocytes from patients with lung cancer and their anti-tumor immunity.

[Tanreqing injection promotes the immune function of mice with Lewis lung carcinoma after chemotherapy].

OBJECTIVE: To investigate the effect of Tanreqing injection on immune function of mice with Lewis lung carcinoma treated by chemotherapy and discuss the immunoregulatory function of this herb. METHODS: All mouse models with Lewis lung carcinoma were randomly divided to four groups: model control group, Tanreqing injection group, chemotherapy group and chemotherapy combined with Tanreqing injection group (8 rats in each group). Other 8 normal mice served as a normal control group. After treatment, peripheral blood was collected from the mice of all groups before they were sacrificed. Tumor tissue, femur, thymus and spleen were obtained to perform the following experiments. Tumor mass and volume were first observed. The apoptosis levels of tumor cells and the ratios of CD3⁺T lymphocyte and CD3⁻NK1.1⁺ cells in the infiltrating lymphocytes in the tumor tissues were analyzed by flow cytometry. Thymus indexes (TI) were counted, and the structure of thymus was observed using HE staining. Cytotoxicity of spleen cytotoxic T cells (CTL) were investigated by MTT assay. The number of lymphocytes in the periphery blood and the nucleated cells in femur were also detected, and the expression levels of interferon-γ (IFN-γ) and tumor necrosis factor-α (TNF-α) mRNA in the tumor tissues were studied by reverse transcription PCR. RESULTS: After chemotherapy, TI, the number of the nucleated cells in femur and lymphocytes in peripheral blood of chemotherapy combined with Tanreqing injection group were obviously higher than those in the chemotherapy group. The ratios of CD3⁺T lymphocytes and CD3⁻NK1.1⁺ cells in the infiltrating lymphocytes in the tumor tissues of chemotherapy combined with Tanreqing injection group were also significantly higher than those in the chemotherapy group. Besides, compared with chemotherapy group, cytotoxicity of CTL in chemotherapy combined with Tanreqing injection group was improved notably. Meanwhile, the expression levels of IFN-γ and TNF-α mRNA in tumor tissues of chemotherapy combined with Tanreqing injection group were dramatically higher than those in chemotherapy group. CONCLUSION: Tanreqing injection has certain protective effects on damaged immune function of body with lung carcinoma induced by chemotherapy, and also improves the anti-tumor immune function of the body.