scholarly journals Aberrant DNA methylation of imprinted loci in human spontaneous abortions after assisted reproduction techniques and natural conception

2012 ◽  
Vol 28 (1) ◽  
pp. 265-273 ◽  
Author(s):  
H.-Y. Zheng ◽  
Y. Tang ◽  
J. Niu ◽  
P. Li ◽  
D.-S. Ye ◽  
...  
Keyword(s):  
Dna Methylation ◽  
Assisted Reproduction ◽  
Spontaneous Abortions ◽  
Assisted Reproduction Techniques ◽  
Natural Conception ◽  
Aberrant Dna Methylation

Aberrant DNA Methylation Is Associated with Reduced Response to SRC Inhibition in Primary Human Vestibular Schwannoma Cells

2019 ◽  
Author(s):  
Christine Dinh ◽  
Juan Young ◽  
Olena Bracho ◽  
Rahul Mittal ◽  
Denise Yan ◽  
...  
Keyword(s):  
Dna Methylation ◽  
Vestibular Schwannoma ◽  
Aberrant Dna Methylation

245-LB: Aberrant DNA Methylation as a Contributor to Obesity-Associated Vascular Dysfunction

Diabetes ◽  
2020 ◽  
Vol 69 (Supplement 1) ◽  
pp. 245-LB
Author(s):  
MOHAMED M. ALI ◽  
CHANDRA HASSAN ◽  
MARIO MASRUR ◽  
FRANCESCO BIANCO ◽  
SHANE A. PHILLIPS ◽  
...  
Keyword(s):  
Dna Methylation ◽  
Vascular Dysfunction ◽  
Aberrant Dna Methylation

scholarly journals Neuroblastoma and the epigenome

2021 ◽  
Author(s):  
Irfete S. Fetahu ◽  
Sabine Taschner-Mandl
Keyword(s):  
Dna Methylation ◽  
Histone Modifications ◽  
Disease Diagnosis ◽  
Dna Methyltransferases ◽  
Epigenetic Alterations ◽  
Aberrant Expression ◽  
Tet Proteins ◽  
Relative Paucity ◽  
Underlying Causes ◽  
Aberrant Dna Methylation

AbstractNeuroblastoma (NB) is a pediatric cancer of the sympathetic nervous system and one of the most common solid tumors in infancy. Amplification of MYCN, copy number alterations, numerical and segmental chromosomal aberrations, mutations, and rearrangements on a handful of genes, such as ALK, ATRX, TP53, RAS/MAPK pathway genes, and TERT, are attributed as underlying causes that give rise to NB. However, the heterogeneous nature of the disease—along with the relative paucity of recurrent somatic mutations—reinforces the need to understand the interplay of genetic factors and epigenetic alterations in the context of NB. Epigenetic mechanisms tightly control gene expression, embryogenesis, imprinting, chromosomal stability, and tumorigenesis, thereby playing a pivotal role in physio- and pathological settings. The main epigenetic alterations include aberrant DNA methylation, disrupted patterns of posttranslational histone modifications, alterations in chromatin composition and/or architecture, and aberrant expression of non-coding RNAs. DNA methylation and demethylation are mediated by DNA methyltransferases (DNMTs) and ten-eleven translocation (TET) proteins, respectively, while histone modifications are coordinated by histone acetyltransferases and deacetylases (HATs, HDACs), and histone methyltransferases and demethylases (HMTs, HDMs). This article focuses predominately on the crosstalk between the epigenome and NB, and the implications it has on disease diagnosis and treatment.

scholarly journals The causes of infertility in women presenting to gynaecology clinics in Harare, Zimbabwe; a cross sectional study

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Mugove G. Madziyire ◽  
Thulani L. Magwali ◽  
Vasco Chikwasha ◽  
Tinovimba Mhlanga
Keyword(s):  
Assisted Reproduction ◽  
Cross Sectional Study ◽  
Male Factor ◽  
Cross Sectional ◽  
Unprotected Sexual Intercourse ◽  
Assisted Reproduction Techniques ◽  
Public Facilities ◽  
Tubal Blockage ◽  
Private And Public

Abstract Background Infertility affects 48.5 million couples globally. It is defined clinically as failure to conceive after 12 months or more of regular unprotected sexual intercourse. The contribution of various aetiological factors to infertility differs per population. The causes of infertility have not been assessed in Zimbabwe. Our objectives were to determine the reproductive characteristics, causes and outcomes of women presenting for infertility care. Methods A retrospective and prospective study of women who had not conceived within a year of having unprotected intercourse presenting in private and public facilities in Harare was done. A diagnosis was made based on the history, examination and results whenever these were deemed sufficient. Data was analysed using STATA SE/15. A total of 216 women were recruited. Results Of the 216 women recruited, two thirds (144) of them had primary infertility. The overall period of infertility ranged from 1 to 21 years with an average of 5.6 ± 4.7 years whilst 98 (45.4%) of the couples had experienced 2–4 years of infertility and 94 (43.5%) had experience 5 or more years of infertility. About 1 in 5 of the women had irregular menstrual cycles with 10 of them having experienced amenorrhoea of at least 1 year. Almost half of the participants (49%) were overweight or obese. The most common cause for infertility was ‘unexplained’ in 22% of the women followed by tubal blockage in 20%, male factor in 19% and anovulation in 16%. Of the 49 (22.7%) women who conceived 21(9.7%) had a live birth while 23 (10.7%) had an ongoing pregnancy at the end of follow up. Thirty-seven (17.1%) had Assisted Reproduction Techniques (ART) in the form of Invitro-fertilisation/Intracytoplasmic Sperm Injection (IVF/ICSI) or Intra-Uterine Insemination (IUI). Assisted Reproduction was significantly associated with conception. Conclusion Most women present when chances of natural spontaneous conception are considerably reduced. This study shows an almost equal contribution between tubal blockage, male factor and unexplained infertility. Almost half of the causes are female factors constituted by tubal blockage, anovulation and a mixture of the two. Improved access to ART will result in improved pregnancy rates. Programs should target comprehensive assessment of both partners and offer ART.

scholarly journals Hypermethylation of mismatch repair gene hMSH2 associates with platinum-resistant disease in epithelial ovarian cancer

2019 ◽  
Vol 11 (1) ◽  
Author(s):  
Hua Tian ◽  
Li Yan ◽  
Li Xiao-fei ◽  
Sun Hai-yan ◽  
Chen Juan ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Ovarian Cancer ◽  
Dna Methylation ◽  
Epithelial Ovarian Cancer ◽  
Upstream Region ◽  
Platinum Resistance ◽  
Maldi Tof Mass Spectrometry ◽  
Platinum Resistant ◽  
Aberrant Dna Methylation ◽  
Low Expression

Abstract Purpose One major reason of the high mortality of epithelial ovarian cancer (EOC) is due to platinum-based chemotherapy resistance. Aberrant DNA methylation may be a potential mechanism underlying the development of platinum resistance in EOC. The purpose of this study is to discover potential aberrant DNA methylation that contributes to drug resistance. Methods By initially screening of 16 platinum-sensitive/resistant samples from EOC patients with reduced representation bisulfite sequencing (RRBS), the upstream region of the hMSH2 gene was discovered hypermethylated in the platinum-resistant group. The effect of hMSH2 methylation on the cellular response to cisplatin was explored by demethylation and knockdown assays in ovarian cancer cell line A2780. Matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) mass spectrometry was employed to examine the methylation levels of hMSH2 upstream region in additional 40 EOC patient samples. RT-qPCR and IHC assay was used to detect the hMSH2 mRNA and protein expression in extended 150 patients. Results RRBS assay discovered an upstream region from − 1193 to − 1125 of hMSH2 was significant hypermethylated in resistant EOC patients (P = 1.06 × 10−14). In vitro analysis demonstrated that global demethylation increased cisplatin sensitivity along with a higher expression of the hMSH2 mRNA and protein. Knockdown hMSH2 reduced the cell sensitivity to cisplatin. MALDI-TOF mass spectrometry assay validated the strong association of hypermethylation of hMSH2 upstream region with platinum resistance. Spearman’s correlation analysis revealed a significantly negative connection between methylation level of hMSH2 upstream region and its expression. The Kaplan-Meier analyses showed the high methylation of hMSH2 promoter region, and its low expressions are associated with worse survival. In multivariable models, hMSH2 low expression was an independent factor predicting poor outcome (P = 0.03, HR = 1.91, 95%CI = 1.85–2.31). Conclusion The hypermethylation of hMSH2 upstream region is associated with platinum resistant in EOC, and low expression of hMSH2 may be an index for the poor prognosis.

Reply to: “Development of an MSI-positive colon tumor with aberrant DNA methylation in a PPAP patient”

2019 ◽  
Vol 65 (6) ◽  
pp. 513-514 ◽  
Author(s):  
Pilar Mur ◽  
Claire Palles ◽  
Ian Tomlinson ◽  
Laura Valle
Keyword(s):  
Dna Methylation ◽  
Colon Tumor ◽  
Aberrant Dna Methylation
Sign in / Sign up

Export Citation Format

Share Document