Research on inhibition mechanism of chlorogenic acid for colorectal cancer cell line HCT116 / 中草药

Objective To discuss the inhibition mechanism of chlorogenic acid for colorectal cancer cell line HCT116. Methods Colorectal cancer cell line HCT116 were treated with chlorogenic acid, and the untreated group was blank control. Then, the gene expression chip was used to screen the differential expression gene before and after processing, the Real-time PCR technique was used to identify IGFBP3, MALAT1, SOX4, and NDRG1, and the Western blotting detected the level of protein expression of NDRG1, which belongs to up-regulated gene. Results The gene expression spectra chip test showed that there were 161 up-regulated expression gene of colorectal cancer (the fold change was larger than 2), and 64 down-regulated expression genes (the fold change was less than 0.5) after chlorogenic acid treatment. Also, these genes were mainly related to the function of cell signal transduction, biological process and cellular component. The results of Real time PCR showed that the mRNA expression of IGFBP3 and NDRG1 were up-regulated significantly (P < 0.05) after chlorogenic acid treatment. Western Blotting results showed that the NDRG1 gene protein expression was up-regulated significantly (P < 0.05) after chlorogenic acid treatment. Conclusion The gene expression spectrum chip combined the Real-time PCR technology, which were used to screen the differential expression gene before and after the chlorogenic acid treatment, in order to reveal the inhibition mechanism of chlorogenic acid for colorectal cancer cells.

Expression and significance of NDRG1, p53 and VEGF in esophageal squamous cell carcinoma / 肿瘤研究与临床

ObjectiveTo study the expression and significance of NDRG1(N-myc downstream regulated gene-1), p53 and VEGF in esophageal squamous cell carcinoma (ESCC). MethodsNDRG1, p53 and VEGF protein were detected by immunohistochemistry (IHC, SP method) in 20 cases of normal esophageal squamous epithelium and 78 cases of ESCC.ResultsThe results of IHC shows that in normal esophageal squamous epithelium and esophageal squamous cell carcinoma,the positive rate of NDRG1 was 100.0 ％(20/20) and 55.1％ (43/78) respectively, p53 was 0 (0/20) and 65.4 ％ (51/78) respectively, VEGF was 30.0 ％(6/20)and 67.9 ％(53/78)respectively,all had statistical significance.There was inverse correlationof NDRG1 expression and lymphatic invasion(r =-0.237,P = 0.036).However expression of NDRG1 was no statistical significance with patient' s age,gender,grade,TNM stage,patient' s five year survival.The expression of p53 was inverse correlated with NDRG1,and the expression of VEGF was inverse correlated with NDRG1 (r =-0.331, P = 0.003). ConclusionNDRG1 may be a new tumor suppress gene and play an important role in the development and metastasis of ESCC.

NDRG1 protein overexpression in malignant thyroid neoplasms

OBJECTIVES: The aim of this study was to examine the expression of the N-myc downstream-regulated gene 1 protein in benign and malignant lesions of the thyroid gland by immunohistochemistry. INTRODUCTION: N-myc downstream-regulated gene 1 encodes a protein whose expression is induced by various stimuli, including cell differentiation, exposure to heavy metals, hypoxia, and DNA damage. Increased N-myc downstream-regulated gene 1 expression has been detected in various types of tumors, but the role of N-myc downstream-regulated gene 1 expression in thyroid lesions remains to be determined. METHODS: A tissue microarray paraffin block containing 265 tissue fragments corresponding to normal thyroid, nodular goiter, follicular adenoma, papillary thyroid carcinoma (classical pattern and follicular variant), follicular carcinoma, and metastases of papillary and follicular thyroid carcinomas were analyzed by immunohistochemistry using a polyclonal anti- N-myc downstream-regulated gene 1 antibody. RESULTS: The immunohistochemical expression of N-myc downstream-regulated gene 1 was higher in carcinomas compared to normal thyroid glands and nodular goiters, with higher expression in classical papillary thyroid carcinomas and metastases of thyroid carcinomas (P < 0.001). A combined analysis showed higher immunohistochemical expression of NDRG1 in malignant lesions (classical pattern and follicular variant of papillary thyroid carcinomas, follicular carcinomas, and metastases of thyroid carcinomas) compared to benign thyroid lesions (goiter and follicular adenomas) (P = 0.043). In thyroid carcinomas, N-myc downstream-regulated gene 1 expression was significantly correlated with a more advanced TNM stage (P = 0.007) and age, metastasis, tumor extent, and size (AMES) high-risk group (P = 0.012). CONCLUSIONS: Thyroid carcinomas showed increased immunohistochemical N-myc downstream-regulated gene 1 expression compared to normal and benign thyroid lesions and is correlated with more advanced tumor stages.

Study on the methylation status of NDRG-1 gene in breast cancer and its reversion in vitro / 肿瘤

Objective:To investigate the methylation status of N-myc downstream regulated gene-1(NDRG-1) gene in breast cancer and the effects of methylation enzyme inhibitor 5-Aza-2'-deoxycytidine (5-Aza-CdR) on growth and expression of NDRG-1 mRNA in human breast cancer cell line T47D.Methods:Sensitive methylation-specific (MSP)-PCR was used to detect the methylation status in the promoter regions of NDRG-1 gene in 47 samples of breast cancer and tumor adjacent tissues and 15 cases of benign breast disease. The change in expression of the tumor suppressor gene NDRG-1 mRNA in cultured T47D cells was detected by RT-PCR before and after 5-Aza-CdR treatment. Cell proliferation was observed by MTT assay.Results:Hypermethylation frequencies of NDRG-1 gene promoter were 46.8% in breast cancer tissues and 21.3% in tumor adjacent tissues. No hypermethylation of NDRG-1 gene was observed in the tissues of breast benign disease. The growth of T47D cells was suppressed obviously after 5-Aza-CdR treatment compared with the control group. RT-PCR showed that compared with the control group, NDRG-1 mRNA expression was increased at different concentrations in 5-Aza-CdR treatment group. Conclusion:The promoter methylation status of NDRG-1 gene was significantly related with the occurrence of breast carcinoma. 5-Aza-CdR could effectively reverse the methylation of NDRG-1 gene and recover its expression, thereby inhibiting the growth of tumor cells.

Biological function of NDRG1 and its roles in tumorigenesis / 国际肿瘤学杂志

N-myc downstream-regulated gene 1 ( NDRG1 ), a member of the NDRG gene family, is a cell proliferation and differentiation related gene which usually express in various human tissues, especially higher in kidney, prostate and placenta. A variety of studies have reported that NDRG1 is correlated with cell proliferation and formation of periphery nerve sheath which might be regulated by hypoxia, anti-oncogene and metallic ion metabolism. Although NDRG1 gene expresses abnormally in tumor tissue, which is probably involved in tumorigenesis, development and metastasis, the exact role of NDRG1 in tumorigenesis is not clearly defined and further studies need to be done.

Molecular Genetics of Autosomal-Recessive Demyelinating Charcotmarie-Tooth Disease (Review Article) / Монголын Анагаах Ухаан

Charcot-Marie-Tooth disease (CMT) is a clinically and genetically heterogenous group of disorders. Useful classifi cation is still clinical and electrophysiological classifi cation that divides CMT into CMT type 1 - demyelinating form and CMT type 2 - axonal form. An intermediate type is also increasingly being determined. Inheritance can be autosomal dominant, X-linked and autosomal recessive (AR). In this review, we will focus on the clinical and/or electrophysiological findings and molecular genetics of ARCMT1 (CMT4). Ten genes, GDAP1, MTMR2, MTMR13, SH3TC2, NDRG1, EGR2, PRX, CTDP1, FGD4 and SAC3 have been identifi ed in the CMT4A, CMT4B1, CMT4B2, CMT4C, CMT4D, CMT4E, CMT4F, CCFDN, CMT4H and CMT4J types, respectively. In addition, susceptibility locus on chromosome 10q23 has been found for CMT4G disease. Molecular genetics of demyelinating ARCMT are large disabilities of proteins in Schwann cells and their functions (transcriptional factor, protein transport, protein sorting, intra/extra cellular compartments, signal transduction, cell division, and cell differentiation). It has been rising necessary requirements to defi ne clinical and genetic subtypes of the ARCMT1, prevent from disease, give reproductive and genetic counselling, and develop methods for reducing and clear disease risk factor.

Up-Regulation of Differentiation Related Gene-1 Expression in the Androgen Independent Prostate Cancer / 대한비뇨기과학회지

PURPOSE: To determine whether the up-regulation of the differentiation related gene (Drg-1) enhances the progression of prostate cancer into the androgen independent phenotype, via escaping androgen signal transduction. MATERIALS AND METHODS: A full length of Drg-1 cDNA was obtained using the Drg-1 primer, which was inserted into LNCaP cells. The sensitivities of dihydrotestosterone and bicalutamide were then examined. In addition, the level of the Drg-1 gene expression was examined in derivatives of the LNCaP cell lines obtained from the orthotopic animal model. RESULTS: The Drg-1 transfected LNCaP cells, which highly expressed the Drg-1, were established (LNCaP/D2). The LNCaP/D2 slowly grew in a culture medium, supplemented with 10% charcoal stripped fetal bovine serum, whereas the control cells did not. When the sensitivities of DHT and bicalutamide were examined, the PC-3 and LNCaP/D2 cells were not sensitive to either. The metastatic androgen independent prostate cancer cells (LNCaP-AI-Lung), which were obtained from the orthotopic animal model, showed higher levels of Drg-1 expression than the parental cells. CONCLUSIONS: Androgen dependent prostate cancer cells, expressing high levels of the Drg-1 gene, behave like androgen independent prostate cancer cells. This finding suggest that the Drg-1 gene may play an important role in the initiation of an androgen-independent state.

Correlation of NDRG1 gene with liver tissue differentiation and hepatocarcinogenesis / 北京大学学报(医学版)

Objective: To detect the expression profile of NDRG1 gene in different tissues and cell lines and explore the relationship of NDRG 1 with liver tissue differentiation and hepatocarcinogenesis. Methods: The expression profiles of NDRG 1 in hepatocellular carcinoma (HCC) tissues, paired noncancerous liver (PNL) tissues, adult normal liver (NL) tissues, baby mouse liver tissues and fetal liver tissues in different developmental stages and cultured cell lines were performed using RT PCR and Northern Blot analysis. Results: Expression of NDRG 1 was significantly up regulated in HCC tissues compared to that of NL tissues and PNL tissues, however, the expressions of NDRG1 in NL and PNL tissues showed no evident difference. In ten cell lines, the highest expression was in the 293T human kidney cell line, the next one in liver cell L02, and the lowest one in the undifferentiated HLE cell line. Expression of NDRG1 in liver tissues enhanced with the development of the baby mouse and human fetus. Conclusion: NDRG 1 is probably related to the liver cell differentiation and is highly expressed in the specific stage of the differentiation. However, it could not be recognized as a marker of differentiation. The high expression of NDRG 1 in HCC indicates that HCC is not just distributed to a simple de differentiation. Much more study is necessary in understanding the comprehensive relationship of the disorder proliferation and differentiation of HCC and the related genes.