scholarly journals DNA methylation in the upstream CpG island of the GPER locus and its relationship with GPER expression in colon cancer cell lines

2020 ◽  
Author(s):  
Uttariya Pal ◽  
Sujasha Ghosh ◽  
Anil Mukund Limaye

AbstractThe seven-transmembrane G-protein coupled estrogen receptor (GPER) relays short-term non-genomic responses in target cells and tissues. It is a proposed tumor suppressor, which frequently undergoes down-modulation in primary tumors of the breast, ovary, and endometrium. A study by Liu and co-workers reported the loss of GPER expression in colorectal cancer and attributed it to DNA methylation-dependent silencing. The present study is based on the hypothesis that GPER expression is inversely correlated with methylation in the upstream CpG island (upCpGi) in the GPER locus. Methylation in the upCpGi was analysed by bisulfite sequencing and correlated with GPER expression in a panel of colon cancer cell lines The bisulfite sequencing results show the presence of a differentially methylated region (DMR) comprising of the downstream eight CpGs of the upCpGi. Methylation in the DMR correlated inversely with GPER expression. We compared two cell lines, namely SW620 and COLO-320DM, in terms of their viability in response to varying concentrations of G1, a GPER specific agonist, which is known to induce cell cycle arrest and apoptosis in colon cancer cell lines. SW-620 cells, which had the least methylated DMR and the highest level of GPER expression, showed significant loss of viability with 1 μM G1. On the other hand, COLO-320DM, which had the most methylated DMR and the lowest level of GPER expression, did not show a significant response to 1 μM G1. At 5 μM G1, SW620 cells showed a greater reduction in viability than COLO-320DM cells. Our study demonstrates the inverse correlation between DNA methylation in the DMR and GPER expression. GPER is a non-canonical form of estrogen receptor, and estrogen is believed to exert its oncoprotective effect in the colon via GPER. DNA methylation-dependent silencing of GPER may, at least in part, the underlying reason behind the loss of estrogen’s oncoprotective effect in the colon. Future studies should explore the utility of DNA methylation in the upCpGi, particularly the DMR, in diagnosis or prognosis.

2006 ◽  
Vol 28 (5-6) ◽  
pp. 259-272 ◽  
Author(s):  
Guro E. Lind ◽  
Kristine Kleivi ◽  
Gunn I. Meling ◽  
Manuel R. Teixeira ◽  
Espen Thiis-Evensen ◽  
...  

Background: Gene silencing through CpG island hypermethylation is a major mechanism in cancer development. In the present study, we aimed to identify and validate novel target genes inactivated through promoter hypermethylation in colorectal tumor development. Methods: With the use of microarrays, the gene expression profiles of colon cancer cell lines before and after treatment with the demethylating agent 5-aza-2′-deoxycytidine were identified and compared. The expression of the responding genes was compared with microarray expression data of primary colorectal carcinomas. Four of these down-regulated genes were subjected to methylation-specific PCR, bisulphite sequencing, and quantitative gene expression analysis using tumors (n=198), normal tissues (n=44), and cell lines (n=30). Results: Twenty-one genes with a CpG island in their promoter responded to treatment in cell lines, and were simultaneously down-regulated in primary colorectal carcinomas. Among 20 colon cancer cell lines, hypermethylation was subsequently identified for three of four analyzed genes, ADAMTS1 (85%), CRABP1 (90%), and NR3C1 (35%). For the latter two genes, hypermethylation was significantly associated with absence or reduced gene expression. The methylation status of ADAMTS1, CRABP1, and NR3C1 was further investigated in 116 colorectal carcinomas and adenomas. Twenty-three of 63 (37%), 7/60 (12%), and 2/63 (3%) adenomas, as well as 37/52 (71%), 25/51 (49%), and 13/51 (25%) carcinomas were hypermethylated for the respective genes. These genes were unmethylated in tumors (n=82) from three other organs, prostate, testis, and kidney. Finally, analysis of normal colorectal mucosa demonstrated that the observed promoter hypermethylation was cancer-specific. Conclusion: By using a refined microarray screening approach we present three genes with cancer-specific hypermethylation in colorectal tumors, ADAMTS1, CRABP1, and NR3C1.


2008 ◽  
Vol 68 (18) ◽  
pp. 7258-7263 ◽  
Author(s):  
Eloisi C. Lopes ◽  
Ester Valls ◽  
Maria E. Figueroa ◽  
Alexander Mazur ◽  
Fan-Guo Meng ◽  
...  

2015 ◽  
Vol 26 (8) ◽  
pp. 818-826 ◽  
Author(s):  
Nathan Farias ◽  
Nelson Ho ◽  
Stacey Butler ◽  
Leanne Delaney ◽  
Jodi Morrison ◽  
...  

2019 ◽  
Vol 9 (4) ◽  
pp. 341-348 ◽  
Author(s):  
Ibrahim Awad Mohammed ◽  
Muhammad Nadeem Akhtar ◽  
Foo Jhi Biau ◽  
Yin Sim Tor ◽  
Seema Zareen ◽  
...  

<P>Background: Breast cancer and human colon cancer are the most common types of cancer in females and males, respectively. Breast cancer is the most common type of cancer after lung and colon cancers. Natural products are an important source for drug discovery. Boesenbergia rotunda (L.) Mansf. is commonly known as finger root, belonging to the Zingiberaceae family. </P><P> Objective: The aim of this study to isolate some natural compounds from the rhizomes of B. rotunda (L.) Mansf., and to investigate their cytotoxicity against the human triple-negative breast cancer cell (MDA-MB-231) and HT-29 colon cancer cell lines. </P><P> Methods: The dried rhizomes of B. rotunda were extracted with methanol. The methanolic extract was further used for solvent-solvent extraction. Bioassay-guided extraction and isolation of the rhizomes of the B. rotunda exhibited cytotoxic properties of hexane and dichloromethane fractions. </P><P> Results: Six major chemical constituents, pinostrobin (1), pinostrobin chalcone (2), cardamonin (3), 4,5-dihydrokawain (4), pinocembrin (5), and alpinetin (6) were isolated from the rhizomes of the B. rotunda. All the chemical constituents were screened against the human triple-negative breast cancer cell (MDA-MB-231) and HT-29 colon cancer cell lines. The compound cardamonin (3) (IC50 = 5.62&#177;0.61 and 4.44&#177;0.66 &#181;g/mL) and pinostrobin chalcone (2), (IC50 = 20.42&#177;2.23 and 22.51&#177;0.42 μg/mL) were found to be potent natural cytotoxic compounds against MDA-MB-231 and HT-29 colon cancer cell lines, respectively. </P><P> Conclusion: Cardamonin (3) and pinostrobin chalcone (2) were found to be the most potential natural compounds against breast cancer cell line MDA-MB-231 and colon cancer HT-29 cell line.</P>


1993 ◽  
Vol 11 (5-6) ◽  
pp. 225-237
Author(s):  
Udo Schumacher ◽  
Dhia Mukthar ◽  
Thomas Schenker

A panel of monoclonal antibodies (n=72 including controls) directed against lung cancer antigens was screened immunohistochemically against a panel of seven human lung cancer cell lines (including small cell carcinoma, squamous cell carcinoma, adenocarcinoma and mesothelioma), six human breast cancer cell lines and one human colon cancer cell line, The majority of the antibodies (n=42) reacted also with antigens present on breast and colon cancer cell lines, This cross reactivity especially between lung and breast cancer cell lines is not altogether unexpected since antigens common to breast and lung tissue including their neoplasms such as MUC1 antigen have been described, Our results indicate that epitopes shared by lung and breast cancers are probably more common than previously thought. The relevance for prognosis and therapy of these shared antigens, especially as disease markers in breast cancer, has to be investigated.


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