Results and lessons from dual extraction of DNA and RNA from formalin-fixed paraffin-embedded breast tumor tissues for a large Cancer epidemiologic study.

Background: The use of archived formalin-fixed paraffin-embedded (FFPE) tumor tissues has become a common practice in clinical and epidemiologic genetic research. Simultaneous extraction of DNA and RNA from FFPE tissues is appealing but can be practically challenging. Here we report our results and lessons learned from processing FFPE breast tumor tissues for a large epidemiologic study.

Evaluation of microRNA expression profiles and their associations with risk alleles in lymphoblastoid cell lines of familial ovarian cancer.

Interindividual variations of microRNA expression are likely to influence the expression of microRNA target genes and, therefore, contribute to phenotypic differences in humans, including cancer susceptibility. Whether microRNA expression variation has any role in ovarian cancer development is still unknown. Here, we evaluated microRNA expression profiles in lymphoblastoid cell lines from 74 women with familial ovarian cancer and 47 unrelated controls matched on gender and race.

A pilot study of circulating miRNAs as potential biomarkers of early stage breast cancer.

Background: To date, there are no highly sensitive and specific minimally invasive biomarkers for detection of breast cancer at an early stage. The occurrence of circulating microRNAs (miRNAs) in blood components (including serum and plasma) has been repeatedly observed in cancer patients as well as healthy controls. Because of the significance of miRNA in carcinogenesis, circulating miRNAs in blood may be unique biomarkers for early and minimally invasive diagnosis of human cancers.

Length heteroplasmies in human mitochondrial DNA control regions and breast cancer risk.

It has been proposed that the presence of heteroplasmy in the hypervariable (HV) regions of the mitochondrial DNA (mtDNA) may be an indicator of mitochondrial genome instability, mtDNA dysfunction, and, thus, may be associated with increased cancer risk. However, whether heteroplasmy in the HV regions of mtDNA could be a risk predictor of oxidative stress-related human cancers, such as breast cancer, remains to be determined. To explore the role of heteroplasmy in the HV regions of mtDNA in breast cancer etiology, we analyzed heteroplasmy in the HV regions of mtDNA in whole blood from 103 patients with breast cancer and 103 matched control subjects.

Differences in oocyte development and estradiol sensitivity among mouse strains.

Mouse oocytes develop in clusters of interconnected cells called germline cysts. Shortly after birth, the majority of cysts break apart and primordial follicles form, consisting of one oocyte surrounded by granulosa cells. Concurrently, oocyte number is reduced by two-thirds.