Relationship between Tumor DNA Methylation Status and Patient Characteristics in African-American and European-American Women with Breast Cancer

Aberrant DNA methylation is critical for development and progression of breast cancer. We investigated the association of CpG island methylation in candidate genes and clinicopathological features in 65 African-American (AA) and European-American (EA) breast cancer patients. Quantitative methylation analysis was carried out on bisulfite modified genomic DNA and sequencing (pyrosequencing) for promoter CpG islands of p16, ESR1, RASSF1A, RARβ2, CDH13, HIN1, SFRP1 genes and the LINE1 repetitive element using matched paired non-cancerous and breast tumor specimen (32 AA and 33 EA women). Five of the genes, all known tumor suppressor genes (RASSF1A, RARβ2, CDH13, HIN1 and SFRP1), were found to be frequently hypermethylated in breast tumor tissues but not in the adjacent non-cancerous tissues. Significant differences in the CDH13 methylation status were observed by comparing DNA methylation between AA and EA patients, with more obvious CDH13 methylation differences between the two patient groups in the ER- disease and among young patients (age<50). In addition, we observed associations between CDH13, SFRP1, and RASSF1A methylation and breast cancer subtypes and between SFRP1 methylation and patient's age. Furthermore, tumors that received neoadjuvant therapy tended to have reduced RASSF1A methylation when compared with chemotherapy naïve tumors. Finally, Kaplan Meier survival analysis showed a significant association between methylation at 3 loci (RASSF1A, RARβ2 and CDH13) and reduced overall disease survival. In conclusion, the DNA methylation status of breast tumors was found to be significantly associated with clinicopathological features and race/ethnicity of the patients

Selecting housekeeping genes as references for the normalization of quantitative PCR data in breast cancer

The common reference genes of choice in relative gene expression studies based on quantitative real time polymerase chain reaction, ACTB and B2M, were shown to be regulated differently in respect to tissue type. In this study, the stability of the selected housekeeping genes for normalizing the qPCR data were identified in the tumor and its adjacent tissues in invasive breast cancer, and the variability of their levels according to the stages and the histopathologic subtypes was analyzed

Promoter methylation and expression changes of CDH1 and P16 genes in invasive breast cancer and adjacent normal breast tissue

We studied the promoter methylation status and expression levels of P16 and CDH1 genes in breast cancer and their adjacent normal tissues with normal control breast tissues, to correlate with their histopathological parameters. Hundred twenty four samples (tumor and adjacent nonmalignant tissues) from 62 breast cancer patients and 4 normal control breast tissues were included in the study. We used methylation specific PCR to evaluate methylation status and quantitative RTPCR to measure the gene expression levels. Methylation incidence of P16 gene and CDH1 gene in tumor tissues were 24.2 % and 33.9 %, respectively. CDH1 and P16 gene were not methylated in normal control tissues. CDH1 underexpression is found to be significant in correlation with advanced stage, histologic type, high tumor grade and lymph node involvement. P16 expression is found not to be significantly related with any histopathological parameters. But 60% of cases which overexpresses P16 were estrogen negative, and 40% of them were histologic grade 3. Both P16 and CDH1 had different expression levels in tumor tissues compared to the adjacent normal tissues and in adjacent normal tissues compared to the normal non-tumor tissues

Novel compound heterozygous variants in GPT2 in a family with microcephaly and intellectual disability

50th European-Society-of-Human-Genetics (ESHG) Conference -- MAY 27-30, 2017 -- Copenhagen, DENMARKWOS: 000489312603024[No abstract available]European Soc Human GenetYale University Mendelian ResearchYale University Mendelian Researc

A pilot study for human tumor/DNA banking: returned more questions than answers.

A pilot study was performed for setting up the Dokuz Eylul University Breast Tumor DNA Bank (DEU-BTB) to facilitate the sharing of tumor DNA/RNA samples and related data from cases collected by collaborators specializing in the breast cancer diseases between 2004 and 2006. The pilot study aimed to provide answers for certain questions on: (1) ethical concerns (informing the volunteer for donating specimen, anonymizing the sample information, procedure on sample request), (2) obtaining and processing samples (technical issues, flowchart), (3) storing samples and their products (storing forms and conditions), (4) clinical database (which clinical data to store), (5) management organization (quality and quantity of personnel, flowchart for management relations), (6) financial issues (establishment and maintenance costs). When the bank had 64 samples, even though it is quite ready to supply samples for a research project, it revealed many questions on details that may be answered in more than one way, pointing that all biobanks need to be controlled by a higher degree of management party which develops and offers quality standards for these establishments