REV7 confers radioresistance of esophagus squamous cell carcinoma by recruiting PRDX2.

Radiotherapy has been widely used for the clinical management of esophageal squamous cell carcinoma. However, radioresistance remains a serious concern that prevents the efficacy of esophageal squamous cell carcinoma (ESCC) radiotherapy. REV7, the structural subunit of eukaryotic DNA polymerase ζ, has multiple functions in bypassing DNA damage and modulating mitotic arrest in human cell lines. However, the expression and molecular function of REV7 in ESCC progression remains unclear. In this study, we first examined the expression of REV7 in clinical ESCC samples, and we found higher expression of REV7 in ESCC tissues compared to matched adjacent or normal tissues. Knockdown of REV7 resulted in decreased colony formation and increased apoptosis in irradiated Eca-109 and TE-1 cells coupled with decreased tumor weight in a xenograft nude mouse model postirradiation. Conversely, overexpression of REV7 resulted in radioresistance in vitro and in vivo. Moreover, silencing of REV7 induced increased reactive oxygen species levels postirradiation. Proteomic analysis of REV7-interacting proteins revealed that REV7 interacted with peroxiredoxin 2 (PRDX2), a well-known antioxidant protein. Existence of REV7-PRDX2 complex and its augmentation postirradiation were further validated by immunoprecipitation and immunofluorescence assays. REV7 knockdown significantly disrupted the presence of nuclear PRDX2 postirradiation, which resulted in oxidative stress. REV7-PRDX2 complex also assembled onto DNA double-strand breaks, whereas REV7 knockdown evidently increased double-strand breaks that were unmerged by PRDX2. Taken together, the present study sheds light on REV7-modulated radiosensitivity through interacting with PRDX2, which provides a novel target for ESCC radiotherapy.

Low carbon city and FDI inflows: evidence from China.

Achieving the goals of "carbon peaking" and "carbon neutrality" becomes one of the important elements of the ecological civilization strategy in China. Based on the strong balanced panel data of 281 prefecture-level cities in China from 2006 to 2019, we investigate the impact of Low-carbon city pilot policy (LCCP policy) on FDI inflows by using the multi-period DID model and intermediary model. After that, we discuss the heterogenous impact in terms of both policy tools and geographic locations. Furthermore, we investigate the spillover effects of the LCCP policy on the FDI inflows of surrounding cities using the Spatial Dubin DID model. The results show that (1) the LCCP policy can significantly attract FDI through reducing compliance costs and promoting technological innovation, and the Bacon decomposition and the placebo test show that the estimation error is small and the regression result is relatively stable; (2) command-mandatory tools have negative effects on FDI, while market-oriented tools can effectively attract FDI in pilot cities, but voluntary tools have no significant effect on FDI in pilot cities; (3) the LCCP policy can significantly promote the inflows of FDI in the eastern and western regions, but it does not significantly promote the FDI in central regions; (4) there is a positive spillover effect on FDI inflows to surrounding cities.

Upregulation of Ying Yang 1 (YY1) suppresses esophageal squamous cell carcinoma development through heme oxygenase-1.

Esophageal squamous cell carcinoma (ESCC) is one of the deadliest malignancies worldwide. Ying Yang 1 (YY1), a ubiquitously expressed GLI-Krüppel zinc finger transcription factor, plays a regulatory role in a variety of fundamental biological processes, such as embryonic development, growth, apoptosis, differentiation and oncogenic transformation. The purpose of this study was to investigate the expression of YY1 in normal and cancerous esophageal tissues and its function in ESCC development. We found that the expression of YY1 mRNA was significantly increased in the tumor tissues, compared with the para-tissues or normal esophageal tissues. The increased expression of YY1 in tumor samples was further confirmed by immunohistochemistry. Furthermore, the overexpression of YY1 conferred radioresistance to the ESCC TE-1 cells and resulted in markedly reduced cell proliferation. Accordingly, the small interfering RNA-mediated silencing of YY1 expression in TE-1 cells resulted in increased proliferation by enhancing the binding of P21 to Cyclin D1 and CDK4, a protein complex known to mediate cell cycle progression. Moreover, besides P21, heme oxygenase-1 (HO-1) was identified as a YY1 downstream effector, as YY1 stimulated HO-1 expression in esophageal cancer cells. YY1 mediated biological function through transcription of HO-1. Forced expression of HO-1 could moderately suppress proliferation of TE-1 cells. The expression of YY1 significantly correlated with that of HO-1 in ESCC tissues. Taken together, we demonstrated overexpression of YY1 in esophageal carcinoma and identified HO-1 as its target.

[Analysis of the evolution of esophageal tumor volume in radiotherapy process using a mathematical model].

The volume change of tumor during radiotherapy processes indirectly reflects the short-term efficacy and the quality of radiotherapy planning. We analyzed clinical data of radiotherapy using a mathematical model in our study. First, we selected eight esophageal carcinoma patients with only using 3DRT and conventional dose fractionation schemes. And then we observed and measured the change of tumor volume during the radiotherapy. Based on the LQ model, repopulation and re-oxygenation in 4Rs, and the kinetics of doomed tumor disintegration, we established the mathematical model of tumor evolution in radiotherapy. And then we used the model to analyze the clinical trial data about esophageal carcinoma with radiotherapy. It was proved that the results of the model almost coincided with the clinical trial data. According to the analysis results, we could get the related radiobiology parameters to estimate biological effective dose and repopulation of patients. The mathematical model could provide reference for assessment of prognosis and further scheme of treatment.

Longitudinal Change of Circulating Tumor Cells During Chemoradiation and Its Correlation with Prognosis in Advanced Nonsmall-Cell Lung Cancer Patients.

Background: This study investigated the association of circulating tumor cells (CTCs) change during chemoradiation with the treatment response and survival profiles in advanced nonsmall-cell lung cancer (NSCLC) patients. Materials and Methods: Fifty-eight advanced NSCLC patients who underwent concurrent chemoradiation were enrolled; their peripheral blood samples were collected before chemoradiation, and at 1 month postchemoradiation, the CTCs were assayed using a CTC-Biopsy system. Moreover, CTCs were classified as CTCs positive and CTCs negative according to CTCs' count, and change of CTCs was calculated. In addition, response of chemoradiation was evaluated at 1 month postchemoradiation, then progression-free survival (PFS) and overall survival (OS) were assessed. Results: Prechemoradiation CTCs positive were associated with increased TNM stage, but not other clinicopathologic characteristics. After chemoradiation, the CTCs' number [1.0 (0.0-3.0) vs. 4.0 (2.0-10.0)] and the percentage of CTC-positive cases (37.9% vs. 77.6%) were both decreased compared to those before chemoradiation. Regarding treatment response, prechemoradiation CTCs positive were associated with lower partial response; postchemoradiation CTCs positive were associated with reduced disease control rate, while CTCs' change during chemoradiation was not associated with treatment response. Kaplan-Meier curves showed that postchemoradiation CTCs positive and increased CTCs' number during chemoradiation were associated with reduced PFS, then multivariate Cox's regression analysis disclosed that they independently predicted decreased PFS. However, no correlation of CTCs' status or CTCs' change with OS was observed. Conclusions: Prechemoradiation CTCs relate to increased TNM stage and worse prognosis in chemoradiation-treated advanced NSCLC patients.

MiR-147a mediated by sodium new houttuyfonate could enhance radiosensitivity of non-small cell lung cancer cells via suppressing STAT3.

BACKGROUND: Radioresistance is a huge obstacle in radiotherapy of non-small cell lung cancer (NSCLC) and how to raise radiosensitivity is an urgent issue. OBJECTIVES: In this study, we investigated the role and molecular mechanism of sodium new houttuyfonate (SNH) in regulation of radiosensitivity of NSCLC cells. MATERIAL AND METHODS: The Cell Counting Kit-8 (CCK-8) was used to measure cell viabilities of NSCLC cell lines A549 and HCC827 after a treatment with SNH (0 mM, 0.1 mM and 0.3 mM). It examined cytotoxicity induced by X-ray (0 Gy, 1 Gy, 2 Gy, 4 Gy, 6 Gy, and 8 Gy) after SNH (0.3 mM) treatment, while flow cytometry was used for apoptosis detection use. Expression of miR-147a or signal transducer and activator of transcription (STAT3) in selected cell lines was assessed through real-time quantitative polymerase chain reaction (RT-qPCR). The CCK-8 was then applied to measure cytotoxicity in cells with miR-147a upregulation or STAT3 suppression under irradiation apoptosis changes were detected with flow cytometry. Thereafter, binding conditions between miR-147a and STAT3 were checked using luciferase reporter assays. Expressions of STAT3 in A549 transfected by siNC, siSTAT3, and by siSTAT3 and miR-147a mimics were checked using RT-qPCR and the phosphorylation of STAT3 was observed using enzyme-linked immunosorbent assay (ELISA). RESULTS: The SNH treatment significantly suppressed cell viabilities and increased apoptosis of lung cancer cells. Cytotoxicity and apoptosis in A549 cells were both enhanced after SNH treatment and raised as the dosages of X-ray grew. MiR-147a presented lower expression in lung cancer cells and was upregulated by SNH, which further contributed to higher cell apoptosis after irradiation. STAT3 directly bound miR-147a and was more expressed in NSCLC cells. Inhibited phosphorylation of STAT3 promoted apoptosis in A549 cells after X-ray exposure. Overexpressed miR-147a inactivated STAT3 signaling, adding to cell apoptosis after irradiation. CONCLUSIONS: SNH-induced miR-147a increased radiosensitivity of A549 cells through inactivation of STAT3 pathway.

DNA methylation enzyme inhibitor RG108 suppresses the radioresistance of esophageal cancer.

Esophageal cancer (EC) is the eighth most common highly aggressive cancer worldwide. The purpose of this study was to investigate the effect of the DNA methyltransferase inhibitor RG108 on the radiosensitivity of EC cells. MTT and clonogenic assays were performed to assess the effect of RG108 on the proliferation and radiosensitivity of Eca­109 and TE­1 human EC cells. The cell cycle progression and alterations in apoptosis were analyzed by flow cytometry. For the in vivo analysis, the Eca­109 cells were inoculated into nude mice to establish tumors. Tissues from xenografts were obtained to detect changes to microvessels and tumor growth by immunohistochemistry (IHC). RNA-seq was used to identify differentially expressed genes. We found that RG108 increased the radiosensitivity of EC cells. Apoptosis and G2/M-phase arrest were induced by X-ray irradiation and were significantly enhanced by RG108. In addition, growth of tumor xenografts from the Eca­109 cells was significantly inhibited by irradiation in combination with RG108. The RNA-seq analysis revealed that, compared with radiation alone, X-ray irradiation in combination with RG108 altered the expression of 121 genes in multiple pathways, including the TGF-ß signaling pathway and the Epstein-Barr virus infection pathway. In conclusion, RG108 induced radiosensitivity in EC cells both in vitro and in vivo.

A Novel Role of Cab45-G in Mediating Cell Migration in Cancer Cells.

Ca(2+)-binding protein of 45 kDa (Cab45), a CREC family member, is reported to be associated with Ca(2+)-dependent secretory pathways and involved in multiple diseases including cancers. Cab45-G, a Cab45 isoform protein, plays an important role in protein sorting and secretion at Golgi complex. However, its role in cancer cell migration remains elusive. In this study, we demonstrate that Cab45-G exhibited an increased expression in cell lines with higher metastatic potential and promoted cell migration in multiple types of cancer cells. Overexpression of Cab45-G resulted in an altered expression of the molecular mediators of epithelial-mesenchymal transition (EMT), which is a critical step in the tumor metastasis. Quantitative real-time PCR showed that overexpression of Cab45-G increased the expression of matrix metalloproteinase-2 and -7 (MMP-2 and MMP-7). Conversely, knock-down of Cab45-G reduced the expression of the above MMPs. Moreover, forced expression of Cab45-G upregulated the level of phosphorylated ERK and modulated the secretion of extracellular proteins fibronectin and fibulin. Furthermore, in human cervical and esophageal cancer tissues, the expression of Cab45-G was found to be significantly correlated with that of MMP-2, further supporting the importance of Cab45-G on regulating cancer metastasis. Taken together, these results suggest that Cab45-G could regulate cancer cell migration through various molecular mechanisms, which may serve as a therapeutic target for the treatment of cancers.

RNA interference for epidermal growth factor receptor enhances the radiosensitivity of esophageal squamous cell carcinoma cell line Eca109.

The present study investigated the effects of small interfering RNAs (siRNAs) specific to the epidermal growth factor receptor (EGFR) gene, on the radiosensitivity of esophageal squamous cell carcinoma cells. EGFR gene siRNAs (EGFR-siRNA) were introduced into esophageal cancer Eca109 cells using Lipofectamine® 2000. The EGFR messenger (m)RNA expression levels, EGFR protein expression and cell growth were assessed using reverse transcription-polymerase chain reaction analysis, western blot analysis and a Cell Counting Kit-8 (CCK-8), respectively. In addition, colony assays were used to determine the inhibitory effects of X-ray radiation on EGFR-silenced cells. EGFR mRNA and protein levels were reduced in the Eca109 cells transfected with EGFR-siRNA. The relative EGFR mRNA expression levels were reduced to 26.74, 9.52 and 4.61% in Eca109 cells transfected with EGFR-siRNA1, 2 and 3, respectively. These mRNA levels were significantly reduced compared with the those of the control group (42.44%; P<0.0001). Transfection with siRNA3 resulted in the greatest reduction in EGFR mRNA expression, with an inhibition rate of 85%. The relative EGFR protein expression levels were reduced to 24.05, 34.91 and 34.14% in Eca109 cells transfected with EGFR-siRNA1, 2 and 3, respectively. These protein levels were significantly reduced compared with those of the control group (78.57%; P<0.0001). Transfection with siRNA1 resulted in the greatest reduction in EGFR protein expression, with an inhibition rate of 72.84%. This reduction in EGFR expression inhibited the proliferation of Eca109 cells, which was identified using the CCK-8 assay. The proliferation inhibition ratio was 28.2%. The cells treated with irradiation in addition to EGFR-siRNA, demonstrated reduced radiobiological parameters (D0, Dq and SF2) compared with those of cells treated with irradiation only, with a sensitization enhancing ratio of 1.5. In conclusion, suppression of EGFR expression may enhance the radiosensitivity of esophageal cancer Eca109 cells and therefore may represent a promising approach for future clinical practice.

Management of primary gastric small cell carcinoma in China.

BACKGROUND: Primary gastric small cell carcinomas (GSCCs) are increasingly identified by endoscopy, and account for 15-20% of all gastric neuroendocrine tumors (NETs). GSCCs have the worst prognosis with the highest rate of metastases. PURPOSE: To provide useful information for clinicians and researchers to better manage patients with GSCC, we studied the clinical features of GSCC and explored the corresponding therapies and prognosis. METHODS: A literature search was conducted through PUBMED, EMBASE, CNKI and WanFang Databases using search terms "stomach" or "gastric" and "small cell carcinoma" or "poorly differentiated neuroendocrine carcinoma", for the period 1999 to 2012. And the cases reported were all from China. Relevant articles were identified through manual review. The reference lists of these articles were reviewed to include further appropriate articles. RESULTS: Two hundred and five eligible cases were analyzed. The median age of patients was 62 years, with a male-to-female ratio of 5.4:1. Of the tumors, 53.17% were located in the upper stomach, 25.37% in the mid, 18.54% in the distal stomach, the remaining 2.93% were found in the total stomach. The mean size was 68mm in maximum diameter, with a range of 15-150 mm. Of the one hundred and thirty-five patients, fifty appeared to be pure GSCCs, eighty-five were mixed. The median overall survival time of 195 patients was 18.50 months. The 1-, 2-, and 5-year average survival rates of 142 patients were 66.75%, 37.13%, and 20.15%, respectively. CONCLUSIONS: GSCC is a rare tumor and it is notoriously aggressive with a strong propensity for both regional and distant spread. Therapies including surgical resection, chemotherapy, and local radiotherapy, by itself or in combination with other treatment, have been used to treat GSCCs in China. To identify the most effective treatment modalities for GSCCs, we still need prospective, multicenter, randomized clinical researches.

Endoscopic survey of esophageal cancer in a high-risk area of China.

AIM: To characterize the histological types of esophageal and cardiac mucosa by endoscopic survey of a population in a high-risk area of esophageal cancer of China. METHODS: A selected cohort of residents in Cixian County during December 2001 and May 2002 was surveyed by using Lugol's staining, followed by computer-based statistical analysis of the data with SPSS 10.0 software. RESULTS: Histologically, the detection rates of squamous epithelial acanthosis, squamous epithelial atrophy, and basal cell hyperplasia in the esophagus were 1.9% (38/2,013), 0.1% (3/2,013) and 0.9% (18/2,013) respectively, and those of mild, moderate, and severe esophagitis were 34.9% (703/2,013), 1.6% (33/2,013) and 0.2% (2/2,013) respectively. Mild, moderate, and severe esophageal dysplasia were detected in 8.6% (172/2,013), 7.8% (157/2,013) and 2.6% (53/2,013) respectively in the selected population, whereas in situ carcinoma, intramucosal carcinoma, invasive squamous carcinoma of the esophagus in 2.5% (50/2,013), 0.2% (4/2,013) and 0.7% (14/2,013) respectively. The detection rates of non-atrophic gastritis and atrophic gastritis of the cardia were 36.3% (730/2,013) and 11.5% (232/2,013) respectively, with mild and severe dysplasia of the cardia detected in 2.5% (51/2,013) and 0.8% (17/2,013), respectively, in this population; the rates of intramucosal adenocarcinoma and invasive adenocarcinoma of the cardia were 0.1% (3/2,013) and 0.8% (17/2,013) respectively. The detection rate of esophageal cancer at early stage was 79.4% (54/68). The survey rate (ratio of examined population to expected population) was 73.8% (2,013/2,725). CONCLUSION: Histologic types of the esophageal and cardiac mucosa were characterized by endoscopic survey in a high-risk population of esophageal cancer, which may help the early detection and treatment of esophageal and cardiac cancers and dysplasia, and reduce the mortality of such malignancies.

Psychometric properties of the Chinese version of the gambling related cognitions scale in Chinese mainland sample.

The English items of Gambling Related Cognitions Scale (GRCS) were first developed and validated by community-based population in 2004. The scale is now becoming a validated and reliable instrument to assess gambling related cognitions in the gambling literature of the West. The present study recruited 730 general adult Chinese individuals to validate the Chinese version of Gambling Related Cognitions Scale (GRCS-C). The results of a confirmatory factor analysis of the Chinese data supported the second-order model with five major factors proposed by Oei and Raylu (2006). The overall scale and five factors demonstrated satisfactory internal consistency and test-retest reliability. Construct validity and concurrent validity of GRCS-C was also sound suggesting that the GRCS-C is a valid and reliable instrument for assessing gambling related cognition among non-clinical Chinese individuals.

Expression of YY1 correlates with progression and metastasis in esophageal squamous cell carcinomas.

OBJECTIVE: Esophageal squamous cell carcinoma (ESCC) is one of the deadliest cancers worldwide. Yin Yang 1 (YY1) is a ubiquitous and multifunctional zinc-finger transcription factor that plays important biological functions in cell homeostasis and tumorigenesis. The purpose of this study was to investigate the expression of YY1 in different ESCC tissues and the potential relationship with clinicopathological features. METHODS: One hundred and four ESCC tissues were collected in this study. The protein levels of YY1 were measured by immunohistochemistry. TE-1 cell invasion in vitro was assessed using the Transwell assay. RESULTS: There were no obvious differences between expression levels in patients over age 64 and those younger than 64, and no noticeable distinction was observed between males and females. However, the YY1 protein level was significantly higher in ESCC tissues with lymph node metastasis than those without lymph node metastasis (P=0.042). Furthermore, the expression of the YY1 protein was stronger in stage III-IV patients than in stage I-II patients (P=0.002), but the protein levels between different histological grades (well, moderate, or poor) showed no statistical significance. Similarly, there was no difference in YY1 expression in patients with or without lymphatic invasion. The Transwell assay revealed that the overexpression of YY1 promoted the invasion ability of TE-1 cells and the inhibition of YY1 could reverse this promotion. CONCLUSION: YY1 expression was associated with TNM stage and lymph node metastasis, suggesting that YY1 can influence human esophageal cancer progression and metastasis.

Analysis of prognostic factors and comparison of prognostic index scores in patients with brain metastases after whole-brain radiotherapy.

BACKGROUND AND PURPOSE: Brain metastases (BMs) are typically associated with poor patient prognosis. Radiation therapy remains the primary treatment for BMs, and patient's prognosis is affected by many factors. The aim of this study was to identify prognostic factors and to compare prognostic index scores in patients with BMs who received whole-brain radiotherapy (WBRT). METHODS: A retrospective prognostic study was conducted in 125 patients with BMs who underwent WBRT between Jan 2008 and Jul 2011. The significance of prognostic variables with regard to survival was determined using univariate and multivariate analyses. A prognostic index (PI) was established based on Cox regression analysis and subgrouping values. The recursive partitioning analysis classes (RPA), basic score for brain metastases (BS-BM), Graded Prognostic Assessment index (GPA), and PI were assessed with regard to prognosis. RESULTS: The median survival time was 213 days (7.1 months). In the univariate analysis of the test group, survival was significantly associated with Karnofsky performance status (KPS) score, the number of BMs, the presence of extracranial metastases, primary tumor status and the number of involved extracranial organs. The multivariate analysis showed that the KPS score (P = 0.002, Wald = 9.700), presence of extracranial metastases (P = 0.018, Wald = 5.604) and primary tumor status (P = 0.001, Wald = 10.212) were significantly correlated with overall survival. RPA, BS-BM and GPA were all closely related to prognosis, as determined using a log-rank test. In predicting the 3- and 6-month survival for patients, the PI was superior to the other three modes. CONCLUSIONS: The three indexes, RPA, BS-BM and GPA, are valid prognostic index models; however, the PI model was the most powerful.

Dihydroartemisinin induces radiosensitivity in cervical cancer cells by modulating cell cycle progression.

OBJECTIVE: To investigate the radiosensitizing effects of dihydroartemisinin (DHA) and its underlying mechanisms in cervical cancer cells. METHODS: This experimental study was conducted between May 2009 and August 2012 in the School of Radiation Medicine and Protection, Soochow University, Suzhou, China. HeLa and Siha cells were assigned as the control group and DHA as treated group. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay, clonogenic assay, cell cycle analysis, and apoptosis analysis were carried out in 2 cell lines of both groups. RESULTS: The inhibitory effect of DHA on the HeLa and Siha cell lines was dependent on both concentration and time. Dihydroartemisinin increased the radiosensitivity of HeLa cells, but not of Siha cells. Apoptosis and the gap2/mitosis (G2/M) phase transition induced by x-irradiation was enhanced by DHA treatment in HeLa cells. Irradiation, combined with DHA, decreased Wee1 expression while increasing Cyclin B1 expression in HeLa cells. CONCLUSION: Dihydroartemisinin potently abrogates G2 checkpoint control in HeLa cells. It can relieve the G2/M arrest induced by irradiation; thus, it can be used as an effective radiosensitizer, which will probably promote the entry of more irradiation-damaged cells into mitosis.

Management of small cell carcinoma of esophagus in China.

PURPOSE: Small cell carcinoma of esophagus (SCEC) is characterized by high malignancy and early metastasis. Although the morbidity of SCEC is very low, few studies of patients with SCEC have been conducted in China, there are no sufficient studies of SCEC conducted and reported in the existing published works, and the choices of treatment remain controversial. In this work, we aim to study the clinical characteristics of SCEC, and explore the corresponding treatment and prognosis through retrospective analysis. MATERIAL AND METHODS: The original articles were identified through the leading digital libraries in China in which the terms "esophagus or esophageal" and "small cell esophageal carcinoma" appeared from 2005 to 2009, 1,176 eligible cases were reviewed for clinical data. Analysis of survival was conducted using the Kaplan-Meier method, and differences were compared using the log-rank test. RESULTS: One thousand one hundred seventy-six eligible cases were analyzed; the median age of patients was 57 years, with a male-to-female ratio of 2.4:1. The number of SCEC accounted for 1.26 % of esophageal cancer treated in the same period. Of the tumors, 89.7 % were located in mid- and lower thoracic esophagus. The average tumor length was 5.4 cm (0.5-17 cm). The median overall survival was 11.1 months for all patients. The 1-, 2-, 3-, and 5-year average overall survival rates of 469 patients was 51.1, 25.5, 13.2, 7.9 %, respectively. The median survival time for LD patients who received systemic treatment was 16.8 m, whereas for those who received local treatment (surgery), the median survival time was 10.1 m; the median survival time for ED patients who received systemic treatment was 7.4 m, compared with 5.8 m for those who received sole treatment (chemotherapy or radiotherapy). CONCLUSIONS: SCEC is a tumor characterized by high malignancy and early metastasis. Although our retrospective analysis cannot provide definitive conclusions on the optimal treatment modality for SCEC, however, our results suggest that systemic treatment combined with surgical resection plays a major role in the therapy of SCEC, systemic therapy may be an effective approach for the treatment of SCEC, and randomized, prospective, multicenter studies are needed to identify optimal treatment modalities for SCEC.

OTUD5 regulates p53 stability by deubiquitinating p53.

BACKGROUND: The p53 tumour suppressor protein is a transcription factor that prevents oncogenic progression by activating the expression of apoptosis and cell-cycle arrest genes in stressed cells. The stability of p53 is tightly regulated by ubiquitin-dependent degradation, driven mainly by its negative regulators ubiquitin ligase MDM2. PRINCIPAL FINDINGS: In this study, we have identified OTUD5 as a DUB that interacts with and deubiquitinates p53. OTUD5 forms a direct complex with p53 and controls level of ubiquitination. The function of OTUD5 is required to allow the rapid activation of p53-dependent transcription and a p53-dependent apoptosis in response to DNA damage stress. CONCLUSIONS: As a novel deubiquitinating enzyme for p53, OTUD5 is required for the stabilization and the activation of a p53 response.

A randomized controlled trial of conventional fraction and late course accelerated hyperfraction three-dimensional conformal radiotherapy for esophageal cancer.

We compared the curative and side-effects in esophageal carcinoma treated by conventional fraction (CF) and late course accelerated hyperfraction (LCAF) three-dimensional conformal radiotherapy. Ninety-eight patients were randomly assigned to two different radiotherapy model groups. Fifty patients were treated using CF three-dimensional conformal radiotherapy at a total dose of 60-68 Gy; 2 Gy/F; 5 fractions/week (median 64 Gy), 48 patients were treated with LCAF (First CF-treated at the dose 40 Gy. Later, LCAF-treated 1.5 Gy/F; 2 fractions/day; 21-27 Gy; a total dose of 61-67 Gy; median 64 Gy). The data showed that the 1-, 2- and 3-year-survival rates in LCAF group were 79.2, 56.3, and 43.8%, compared to 74, 54, and 36% in CF group (P = 0.476). The 1-, 2- and 3-year-local control rates in LCAF group were 81.3, 62.5, and 50%, compared to 78, 58, and 42% in CF group (P = 0.454). In CF group, the incidence of radiation-induced esophagitis was lower than that in LCAF group (72 vs. 93.8%; P = 0.008) and there was no significant difference between rates of radiation-induced pneumonitis in CF and LCAF groups (10 vs. 6.25%; P = 0.498). It was concluded that the 1-, 2- and 3-year-local control and survival rates of esophageal carcinoma patients treated with LCAF were slightly better than CF radiotherapy; however, the radiation side-effects in LCAF group were greater than those in CF group.

[Mechanisms of preventive effect of tetrandrine on acquired multidrug resistance in K562 cells].

This study was purposed to explore the mechanisms of preventive effect of tetrandrine (TTD) on doxorubicin (ADM)-induced multidrug resistance (MDR) in human leukemia cell line K562 from two aspects of the transcription control of MDR1 gene and cell apoptosis. The experiment was divided into 3 groups: group I-blank control; group II-ADM-induced drug-resistance; group III-ADM-induced drug-resistance after pretreatment with TTD. Reverse transcription-PCR (RT-PCR) was used to detect the mRNA expression levels of c-Jun, YB-1 and Survivin genes. Western blot was used to determine the nuclear protein expression levels of c-Jun and YB-1. Flow cytometry was used to assay the apoptosis of cells. The results showed that as compared with group I, the expression levels of c-Jun mRNA and nuclear protein decreased (p < 0.05), as well as the expression levels of YB-1 mRNA and nuclear protein increased in group II (p < 0.05). However, the expression of Survivin mRNA had no change (p > 0.05); the apoptosis rate of cells was 8.31%. As compared with group II, the expression levels of c-Jun mRNA and nuclear protein increased (p < 0.05), expression levels of YB-1 mRNA and nuclear protein as well as Survivin mRNA decreased in group III (p < 0.05). The apoptosis of cells was 97.2%. It is concluded that TTD can inhibit the expression of YB-1 and up-regulate the expression of c-Jun, thus inhibit the expression of MDR1 gene. TTD can also inhibit the expression of Survivin and increase the apoptosis of cells induced by ADM.

[Effect of tetrandrine on the doxorubicin-induced expression of mdr1 gene in K562 cells].

OBJECTIVE: To investigate the effect of tetrandrine (TTD) on doxorubicin-induced mdr1 gene expression and its mechanism. METHODS: MTT assay was used to detect the cytotoxicity of TTD to K562 cells. K562 cells were treated with doxorubicin alone or 0.6 microg/ml doxorubicin combined with various concentrations of TTD. RT-PCR was used to detect the mRNA expression of mdr1 and NF-kappa B. Flow cytometry was used to assay the expression of P-glycoprotein (P-gp). Intracellular rhodamine 123 (Rho123) retention assay was applied to test the P-gp function. RESULTS: After treatment with 0.6 microg/ml doxorubicin for 24 hours, the expressions of mdr1 mRNA, NF-kappa B mRNA and P-gp in K562 cells were increased from 0.171 +/- 0.012, 0.783 +/- 0.090, 7.85 +/- 0.15 to 0.428 +/- 0.012, 1.075 +/- 0.047 and 73.68 +/- 1.84, respectively. The intracellular Rho123 retention was decreased from 711.9 +/- 63.6 to 347.8 +/- 60.6, indicating up-regulation of P-gp function (P<0.05). Pretreatment of K562 cells with 2.0 microg/ml TTD for 24 hours and then incubated for another 24 h with doxorubicin, the expressions of mdr1 mRNA, NF-kappa B mRNA, P-gp and up-regulation of P-gp function induced by doxorubicin were prevented in K562 cells (0.148 +/- 0.006, 0.627 +/- 0.098, 7.18 +/- 0.38 and 799.7 +/- 45.8, respectively P<0.05). But 0.5 microg/ml and 1.0 microg/ml TTD had little effect. CONCLUSIONS: TTD inhibits the expression of mdr1 mRNA, P-gp and up-regulated P-gp function induced by doxorubicin in a dose dependent manner. The mechanism of this effect may be down-regulation of NF-kappa B by TTD.