Dasatinib, paclitaxel, and carboplatin in women with advanced-stage or recurrent endometrial cancer: A pilot clinical and translational study.

PURPOSE: To evaluate the effect of dasatinib therapy on EphA2 signaling in cancers of women with measurable (biopsy amenable) advanced-stage, chemo-naïve primary or recurrent endometrial cancer. Preliminary efficacy was also assessed. PATIENTS AND METHODS: We performed a pilot study of single-agent dasatinib lead-in, followed by triplet dasatinib, paclitaxel, and carboplatin. We measured the downstream effectors of EphA2 signaling in pre- and post-dasatinib treatment biopsy tissue samples; we also determined the severity of adverse events and patients' progression-free survival and overall survival durations. RESULTS: Eighteen patients were recruited and given dasatinib (150 mg orally daily for 14 days), followed by paclitaxel, carboplatin and dasatinib (daily) for six cycles (21-day cycles). Seventeen patients were evaluable for toxicity and 11 patients for response. A reverse phase protein array and proximity ligation assay revealed that CRAF/BRAF dimerization, caveolin-1 level, and Notch pathway signaling were predictive of response and resistance to dasatinib. Overall, the objective response rate was 45% (95% CI: 17%-77%), with median progression-free survival duration of 10.5 months and median overall survival duration of 30.4 months. The most common grade 3 or 4 adverse events were neutropenia (76%), thrombocytopenia (53%), anemia (53%), and fatigue (12%). CONCLUSIONS: Caveolin-1 expression, in combination with CRAF/BRAF heterodimerization, is associated with resistance to EphA2 targeting by dasatinib. The triplet combination showed interesting clinical activity in endometrial cancer with acceptable toxicity. Pretreatment with dasatinib may accentuate combination therapy toxicity.

Single HER2-positive tumor cells are detected in initially HER2-negative breast carcinomas using the DEPArray™-HER2-FISH workflow.

BACKGROUND: In breast cancer (BC), overexpression of HER2 on the primary tumor (PT) is determined by immunohistochemistry (IHC) or fluorescence in situ hybridization (FISH) to stratify samples as negative, equivocal and positive to identify patients (pts) for anti-HER2 therapy. CAP/ASCO guidelines recommend FISH for analyzing HER2/neu (ERBB2) gene amplification and for resolving equivocal HER2 IHC results. However, pre-analytical and analytical aspects are often confounded by sample related limitations and tumor heterogeneity and HER2 expression may differ between the PT and circulating tumor cells (CTCs), the precursors of metastasis. We used a validation cohort of BC patients to establish a new DEPArray™-PT-HER2-FISH workflow for further application in a development cohort, characterized as PT-HER2-negative but CTC-HER2/neu-positive, to identify patients with PT-HER2 amplified cells not detected by routine pathology. METHODS: 50 µm FFPE tumor curls from the validation cohort (n = 49) and the development cohort (n = 25) underwent cutting, deparaffinization and antigen retrieval followed by dissociation into a single-cell suspension. After staining for cytokeratin, vimentin, DAPI and separation via DEPArray™, single cells were processed for HER2-FISH analysis to assess the number of chromosome 17 and HER2 loci signals for comparison, either with available IHC or conventional tissue section FISH. CTC-HER2/neu status was determined using the AdnaTest BreastCancer (QIAGEN, Hilden, Germany). RESULTS: Applying CAP/ASCO guidelines for HER2 evaluation of single PT cells, the comparison of routine pathology and DEPArray™-HER2-FISH analysis resulted in a concordance rate of 81.6% (40/49 pts) in the validation cohort and 84% (21/25 pts) in the development cohort, respectively. In the latter one, 4/25 patients had single HER2-positive tumor cells with 2/25 BC patients proven to be HER2-positive, despite being HER2-negative in routine pathology. The two other patients showed an equivocal HER2 status in the DEPArray™-HER2-FISH workflow but a negative result in routine pathology. Whereas all four patients with discordant HER2 results had already died, 17/21 patients with concordant HER2 results are still alive. CONCLUSIONS: The DEPArray™ system allows pure tumor cell recovery for subsequent HER2/neu FISH analysis and is highly concordant with conventional pathology. For PT-HER2-negative patients, harboring HER2/neu-positive CTCs, this approach might allow caregivers to more effectively offer anti-HER2 treatment.

Membrane protected apoptotic trophoblast microparticles contain nucleic acids: relevance to preeclampsia.

Microparticles (MPs) that circulate in blood may be a source of DNA for molecular analyses, including prenatal genetic diagnoses. Because MPs are heterogeneous in nature, however, further characterization is important before use in clinical settings. One key question is whether DNA is either bound to aggregates of blood proteins and lipid micelles or intrinsically associated with MPs from dying cells. To test the latter hypothesis, we asked whether MPs derived in vitro from dying cells were similar to those in maternal plasma. JEG-3 cells model extravillous trophoblasts, which predominate during the first trimester of pregnancy when prenatal diagnosis is most relevant. MPs were derived from apoptosis and increased over 48 hours. Compared with necrotic MPs, DNA in apoptotic MPs was more fragmented and resistant to plasma DNases. Membrane-specific dyes indicated that apoptotic MPs had more membranous material, which protects nucleic acids, including RNA. Flow cytometry showed that MPs derived from dying cells displayed light scatter and DNA staining similar to MPs found in maternal plasma. Quantification of maternal MPs using characteristics defined by MPs generated in vitro revealed a significant increase of DNA(+) MPs in the plasma of women with preeclampsia compared with plasma from women with normal pregnancies. Apoptotic MPs are therefore a likely source of stable DNA that could be enriched for both early genetic diagnosis and monitoring of pathological pregnancies.

Improving enrichment of circulating fetal DNA for genetic testing: size fractionation followed by whole gene amplification.

OBJECTIVE: Among the pitfalls of using cell-free fetal DNA in plasma for prenatal diagnosis is quality of the recovered DNA fragments and concomitant presence of maternal DNA (>95%). Our objective is to provide alternative methods for achieving enrichment and high-quality fetal DNA from plasma. METHODS: Cell-free DNA from 31 pregnant women and 18 controls (10 males and 8 females) were size separated using agarose gel electrophoresis. DNA fragments of 100-300, 500-700 and 1,500-2,000 bp were excised and extracted, followed by whole genome amplification (WGA) of recovered fragments. Levels of beta-globin and DYS1 were measured. RESULTS: Distribution of beta-globin size fragments was similar among pregnant women and controls. Among control male cases, distribution of size fragments was the same for both beta-globin and DYS1. Among maternal cases confirmed to be male, the smallest size fragment (100-300 bp) accounted for nearly 50% (39.76 +/- 17.55%) of the recovered DYS1-DNA (fetal) and only 10% (10.40 +/- 6.49%) of beta-globin (total) DNA. After WGA of plasma fragments from pregnant women, DYS1 sequence amplification was best observed when using the 100-300 bp fragments as template. CONCLUSIONS: Combination of electrophoresis for size separation and WGA led to enriched fetal DNA from plasma. This novel combination of strategies is more likely to permit universal clinical applications of cell-free fetal DNA.

Metronomic chemotherapy enhances the efficacy of antivascular therapy in ovarian cancer.

Metronomic chemotherapy is the frequent administration of low doses of chemotherapeutic agents targeting tumor-associated endothelial cells. We examined the efficacy of metronomic taxanes alone and in combination with AEE788-a dual epidermal growth factor receptor (EGFR) and vascular endothelial growth factor receptor (VEGFR) inhibitor-in an orthotopic mouse model of ovarian cancer. Growth-modulating effects of metronomic and maximum tolerated dose (MTD) regimens on overall survival were tested in vivo using both chemotherapy-sensitive (HeyA8 and SKOV3ip1) and chemotherapy-resistant (HeyA8-MDR) models. Treated tumors were stained for microvessel density (CD31), proliferation index (proliferating cell nuclear antigen), and apoptosis (terminal deoxyribonucleotide transferase-mediated nick-end labeling). The cytotoxic effects of MTD and metronomic dosing were tested with 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assays. Effects of metronomic regimens on circulating endothelial precursors (CEP) and tumor-specific cell-free DNA levels were assessed. In vivo, metronomic docetaxel resulted in significant reduction of tumor growth in the taxane-sensitive cell lines, whereas metronomic docetaxel plus AEE788 had an additive effect resulting in significant prolongation in survival. Combination therapy was effective even in the taxane-resistant model. Metronomic chemotherapy alone and combined with AEE788 resulted in a decrease in the proliferative index and microvessel density of treated tumors, whereas combination therapy increased the apoptotic index (P < 0.001). In vitro, metronomic taxanes caused endothelial cell toxicity at 10- to 100-fold lower concentrations compared with MTD dosing. Metronomic regimens inhibited mobilization of CEPs (P < 0.05) and led to a decrease in cell-free DNA levels (P < 0.05). Our results suggest that metronomic taxane chemotherapy with dual EGFR and VEGFR inhibition is highly efficacious and should be considered for future clinical trials.

Multiparametric liquid biopsy analysis in metastatic prostate cancer.

Molecular profiling of prostate cancer with liquid biopsies, such as circulating tumor cells (CTCs) and cell-free nucleic acid analysis, yields informative yet distinct data sets. Additional insights may be gained by simultaneously interrogating multiple liquid biopsy components to construct a more comprehensive molecular disease profile. We conducted an initial proof-of-principle study aimed at piloting this multiparametric approach. Peripheral blood samples from men with metastatic castrate-resistant prostate cancer were analyzed simultaneously for CTC enumeration, single-cell copy number variations, CTC DNA and matched cell-free DNA mutations, and plasma cell-free RNA levels of androgen receptor (AR) and AR splice variant (ARV7). In addition, liquid biopsies were compared with matched tumor profiles when available, and a second liquid biopsy was drawn and analyzed at disease progression in a subset of patients. In this manner, multiparametric liquid biopsy profiles were successfully generated for each patient and time point, demonstrating the feasibility of this approach and highlighting shared as well as unique cancer-relevant alterations. With further refinement and validation in large cohorts, multiparametric liquid biopsies can optimally integrate disparate but clinically informative data sets and maximize their utility for molecularly directed, real-time patient management.

Stability of placental RNA using dried maternal blood spots.

Having demonstrated successful recovery and detection of placental transcripts from dried blood spots (DBS), various preanalytical conditions were examined to determine optimal handling of samples. The role of several factors was explored, including temperature (4 degrees C versus 25 degrees C), processing time (24 h to 8 weeks), and addition of preservatives (RNA later and formalin) that may interfere with stability and detection of placental transcripts in DBS. mRNA transcripts encoding human glyceraldehyde-3-phosphate dehydrogenase (GAPDH; internal control) and beta-human chorionic gonadotrophin (beta HCG; placental) were analysed by real-time-polymerase chain reaction using DBS from 23 pregnant women. GAPDH and beta HCG transcripts were detected in all samples 24 h after collection. Although treatment of blood with RNA later did not affect RNA recovery, formalin treatment negatively affected RNA recovery from DBS. Temperature did not have a significant effect on levels of either transcript. Storage time caused a significant decrease in GAPDH after 4 weeks (P = 0.014) and beta HCG after 1 week (P = 0.007). Decrease of beta HCG levels after 1 week followed by steady detectable levels for up to 4 weeks suggests two populations of circulating placental transcript exist, a population susceptible to degradation in blood versus a more stable form. Therefore, defining proper parameters for collection and storage of DBS further reinforces reliable analysis of target sequences for clinical testing.

Comprehensive Mutation and Copy Number Profiling in Archived Circulating Breast Cancer Tumor Cells Documents Heterogeneous Resistance Mechanisms.

Addressing drug resistance is a core challenge in cancer research, but the degree of heterogeneity in resistance mechanisms in cancer is unclear. In this study, we conducted next-generation sequencing (NGS) of circulating tumor cells (CTC) from patients with advanced cancer to assess mechanisms of resistance to targeted therapy and reveal opportunities for precision medicine. Comparison of the genomic landscapes of CTCs and tissue metastases is complicated by challenges in comprehensive CTC genomic profiling and paired tissue acquisition, particularly in patients who progress after targeted therapy. Thus, we assessed by NGS somatic mutations and copy number alterations (CNA) in archived CTCs isolated from patients with metastatic breast cancer who were enrolled in concurrent clinical trials that collected and analyzed CTCs and metastatic tissues. In 76 individual and pooled informative CTCs from 12 patients, we observed 85% concordance in at least one or more prioritized somatic mutations and CNA between paired CTCs and tissue metastases. Potentially actionable genomic alterations were identified in tissue but not CTCs, and vice versa. CTC profiling identified diverse intra- and interpatient molecular mechanisms of endocrine therapy resistance, including loss of heterozygosity in individual CTCs. For example, in one patient, we observed CTCs that were either wild type for ESR1 (n = 5/32), harbored the known activating ESR1 p.Y537S mutation (n = 26/32), or harbored a novel ESR1 p.A569S (n = 1/32). ESR1 p.A569S was modestly activating in vitro, consistent with its presence as a minority circulating subclone. Our results demonstrate the feasibility and potential clinical utility of comprehensive profiling of archived fixed CTCs. Tissue and CTC genomic assessment are complementary, and precise combination therapies will likely be required for effective targeting in advanced breast cancer patients.Significance: These findings demonstrate the complementary nature of genomic profiling from paired tissue metastasis and circulating tumor cells from patients with metastatic breast cancer. Cancer Res; 78(4); 1110-22. ©2017 AACR.

Circulating cell-free DNA: a novel biomarker for response to therapy in ovarian carcinoma.

INTRODUCTION: Cell-free DNA (CFDNA) is a reflection of both normal and tumor-derived DNA released into the circulation through cellular necrosis and apoptosis. We sought to determine whether tumor-specific plasma DNA could be used as a biomarker for tumor burden and response to therapy in an orthotopic ovarian cancer model. METHODS: Female nude mice injected intraperitoneally with HeyA8 ovarian cancer cells were treated with either docetaxel alone or in combination with anti-angiogenic agents (AEE788-dual VEGFR and EGFR antagonist or EA5-monoclonal antibody against ephrin A2). Following DNA extraction from plasma, quantification of tumor-specific DNA was performed by real-time PCR using human specific beta-actin primers. The number of genome equivalents (GE/ml) were determined from a standard curve. Apoptosis was assessed by TUNEL staining of treated tumors. RESULTS: The levels of tumor-specific DNA in plasma increased progressively with increasing tumor burden (R2=0.8, p<0.01). Additionally, tumor-specific plasma DNA levels varied following treatment with chemotherapy. In mice with established tumors (19 days following tumor injection), tumor-specific plasma DNA levels increased by 63% at 24 hours following a single dose of docetaxel (15 mg/kg), and then declined to 20% below baseline at 72 hours and were 83% lower than baseline 10 days following therapy. In addition, docetaxel treatment resulted in a significant increase in the apoptotic index at 24 hours (p<0.01). Moreover, in two separate therapy experiments using a combination of cytotoxic chemotherapy with anti-angiogenic agents, tumor-specific plasma DNA levels were significantly higher in mice treated with vehicle compared to the treatment groups. The correlation between tumor weight and tumor-specific DNA in these experiments was 0.71-0.76 (p<0.01). CONCLUSIONS: Our results indicate that tumor-specific CFDNA levels correlate with increasing tumor burden and decline following therapy. Thus, tumor-specific DNA may be a useful surrogate biomarker of therapeutic response and should be evaluated in future clinical trials.

Hypoxia-induced membrane-bound apoptotic DNA particles: potential mechanism of fetal DNA in maternal plasma.

Fetal DNA is found in the plasma of pregnant women that appears to be stable for PCR amplification. Although the underlying mechanism giving rise to this DNA in plasma remains unclear, the source of these fragments may be from apoptotic bodies (Apo-Bodies) created from dying cells. Trophoblast apoptosis is essential for normal placental development, given the enormous amount of proliferation, differentiation, and migration during pregnancy. Through flow cytometric analysis coupled with real-time PCR, our lab has shown that aggregates of acridine orange (AO)-stained material (apoptotic particles) are resistant to DNase treatment, disrupted by sodium dodecyl sulfate (SDS), and contain fetal DNA. Because the placenta continuously re-models in an hypoxic environment, our hypothesis is that fetal DNA in maternal plasma comes from hypoxia-induced dying trophoblasts and that this DNA circulates predominantly in the form of Apo-Bodies. We have developed a model culture system for analysis of Apo-Bodies derived from JEG-3 cells, an extravillous trophoblastic cell line, undergoing various methods of cell death: hypoxia-induced, etoposide-induced, and heat stress (necrosis like)-induced cell death. Under conditions of similar propidium iodide (PI) uptake, suggesting comparable levels of death, both hypoxia- and etoposide-induced Apo-Bodies increase in concentration over time, whereas heat-induced levels of particles remain fairly constant, indicating that production of DNA-associated Apo-Bodies is a continuous process. Hypoxia, which is likely to be responsible for trophoblast cell death in vivo, produced membrane-bound Apo-Bodies containing DNA. Our results are consistent with the characteristics of membrane-bound particles containing fetal DNA found in maternal plasma.

Quantification of total plasma cell-free DNA in ovarian cancer using real-time PCR.

Our objective was to compare the levels of total circulating plasma cell-free DNA (CfDNA) using real-time PCR in patients with late-stage ovarian cancer with those in unaffected controls. Following IRB consent, DNA was extracted from archived frozen plasma of 19 patients with primary ovarian carcinoma and 12 age-matched controls using Qiagen DNA Isolation Kits. Quantification of total CfDNA was performed using real-time PCR with the TaqMan Assay for GAPDH, beta-actin and beta-globin and the number of genome equivalents (GE/mL) were determined from a standard curve. CfDNA levels of these loci were compared between the groups with Student's t-test, with P < 0.05 being statistically significant. The mean age of the patients was 61.6 years (+/-9.6) and of the controls was 54 years (+/-12.2). All patients had high-grade, advanced stage (III or IV) serous ovarian carcinomas. Preoperative CA-125 levels ranged from 43 to 15,626 IU/mL (mean 2487.2 +/- 3686 IU/mL). Total CfDNA in ovarian cancer was higher among patients with ovarian cancer as compared to controls at all three loci: GAPDH (P = 0.022), beta-actin (P = 0.025), and beta-globin (P = 0.0089). CfDNA is elevated in advanced stage disease compared to controls. These preliminary results suggest that total CfDNA in the plasma of patients with ovarian cancer may be useful for noninvasive screening and disease surveillance.

Endocervical fetal trophoblast for prenatal genetic diagnosis.

PURPOSE OF REVIEW: For over a decade, methods of first-trimester, noninvasive prenatal genetic diagnosis have been actively pursued by many investigators. Isolation of fetal trophoblast from endocervical specimens remains an attractive approach, given the greater numbers of fetal cells than in maternal blood and the better potential for fetal-cell identification based on markers specific for a single cell type (trophoblasts). RECENT FINDINGS: Current studies demonstrate feasibility in identification and molecular analysis of fetal trophoblast cells for prenatal genetic testing. Sampling methods involving lavage, cytobrush, or aspiration of cervical specimens, however, have limitations in the recovery of trophoblasts. SUMMARY: Clinical applications await further systematic studies to determine safety and accuracy in recovery.

Somatic DNA alterations in endometriosis: high frequency of chromosome 17 and p53 loss in late-stage endometriosis.

PROBLEM: Genetic predisposition to endometriosis is well established, but the gene(s) involved largely remain unknown. Although endometriosis is considered a benign disease, it displays several features similar to malignancy: altered morphology, disregulated growth, invasion. We hypothesize endometriosis arises as result of somatic DNA alterations occurring in a multi-step process, analogous to origin of neoplasia. Since chromosome 17 and TP53 tumor suppressor gene (TSG) alterations occur frequently in premalignant and malignant tissues, including endometrial and ovarian epithelial carcinomas, we sought to determine if similar somatic changes occur in late stage endometriosis. METHOD OF STUDY: To determine the frequencies of monosomy for chromosome 17, as well as for perturbations of p53 and other loci on 17, two different approaches were used. Fluorescent in situ hybridization (FISH) analysis was used to detect monosomy for the 17 centromere and for the p53 locus. For FISH, archival tissue (n=6) and fresh endometriotic touch preparations were prepared from women (n=8) undergoing extirpation of advanced stage endometriosis. Direct-labeled probes specific for p53 (17p13.1) and for the chromosome 17 alpha-satellite centromere region (1711.1-q11.1) were used to compare single glandular and stromal cells from endometriosis and normal tissue. DNA analysis of polymorphic DNA loci were used to detect loss of heterozygosity (LoH) for other loci on 17. We assessed matched endometriotic and normal DNA (peripheral blood) from women with severe/late stage disease (n=15), studying these dinucleotide markers: HGH (located on 17q22-24), D17S250 (17q11.2-q12) and CHRNB1 (17p13.1). RESULTS: Loss of the chromosome 17 centromere (monosomy) was shown by FISH in some cells from all 14 endometriosis specimens, although in no case did every cell show monosomy 17. In 12 of 14 specimens, significant proportions of cells not only were monosomic for the chromosome 17-centromere (8 to 42% of cells) but also showed loss of p53 locus. In the two remaining cases, p53 loss alone was observed in 8 and 14%. LoH for other alleles on chromosome 17 was observed less often, namely only 3 of 15 specimens for HGH, 1 of 15 for D17S250, and 0 of 15 for CHRNB1. CONCLUSIONS: Our study indicates that perturbations of chromosome 17 in general and the p53 locus in particular occur frequently in severe/late stage endometriosis. That not all cells show loss of whole chromosome 17 or the p53 locus suggests somatic mutation, perhaps occurring late in the pathogenesis of endometriosis. Clonal evolution of endometriosis must depend not only on somatic mutations for p53 but also on other oncogenes or TSG. Alternatively, the clone could begin with a germline or somatic mutation involving a nonneoplastic process, followed by one or more somatic mutations involving an oncogene or TSG like p53. Additional candidate genes clearly must be evaluated in order to determine the precise role chromosome 17 and p53 alterations play in endometriosis; however, additional genes seem unlikely to involve region connoted by HGH, D17S250 or CHRNB1.

Heritability and molecular genetic studies of endometriosis.

Endometriosis is well established as a condition showing heritable tendencies. Polygenic/multifactorial etiology appears far more likely to be the etiology than Mendelian inheritance. The current task is to determine the number and location of genes responsible for endometriosis. This paper shall review the basis for concluding that endometriosis is a genetic disorder of polygenic/multifactorial inheritance and outline selected strategies for identifying the number and location of causative genes. It shall also illustrate our approach to testing the hypothesis that endometriosis bears similarity to neoplasia and, hence, is a multistep phenomenon of clonal origin.

Genetic basis of endometriosis.

Endometriosis is a complex gynecologic disorder that has long been recognized as showing heritable tendencies, with recurrence risks of 5-7% for first-degree relatives. Familial and epidemiologic studies support that this disease is a genetic disorder of polygenic/multifactorial inheritance. The current investigational challenge is to determine the number and location of causative genes. Recent advances in molecular technology make identification and elucidation of these genes now possible. In this review, we update previous communications in which we also reviewed heritability studies supporting polygenic/multifactorial inheritance, discuss the scientific basis of genomewide strategies for identifying causative genes, and identify potential candidate genes.

Genetic counseling in translocations.

Advances in the treatment of male infertility-specifically intracytoplasmic sperm injection have now resulted in greater recognition of the clinical significance of genetic translocations. This article focuses on the different types of translocations (Robertsonian, reciprocal) as well as on the prevalence and incidence of translocations in infertile and other populations. The authors contrast theoretical and empiric meiotic segregation patterns in the different clinical settings of traditional prenatal genetic diagnosis and preimplantation genetic diagnosis. In particular, the significance of a higher prevalence of unbalanced blastomeres is discussed.

Endothelial precursor cells in the peripheral blood of pregnant women.

OBJECTIVE: To determine whether primitive endothelial precursor cells are present in the peripheral blood of pregnant compared with nonpregnant subjects and whether these precursor cells are of fetal or maternal origin. METHODS: Peripheral blood mononuclear cells from 13 pregnant women in the second trimester and from ten nonpregnant women and men were cultured for 8-10 weeks under conditions that promoted endothelial cell development. Early outgrowth (1 week culture) and late outgrowth (4-6 weeks) colonies were observed, their endothelial nature was investigated, and fluorescence in situ hybridization was performed to determine the origin of the colonies from pregnant women's specimens. RESULTS: Peripheral blood mononuclear cell cultures from all pregnant women and all nonpregnant controls yielded early-outgrowth endothelial cells. Late-outgrowth endothelial cells were observed in 61.5% (eight of 13) of pregnant subjects, but in none of the ten nonpregnant controls (chi(2) test; P <.01). The adherent cells stained positively for von Willebrand factor and incorporated Dil-Ac-LDL, confirming their endothelial origin. Fluorescence in situ hybridization analysis showed only X chromosome-specific signals and no Y chromosome-specific signals in the cells from the late-outgrowth endothelial cells in all pregnant women carrying either a male (n = 5) or a female (n = 8) fetus. CONCLUSION: Primitive endothelial precursor cells are present in most pregnant women during the second trimester. These cells appear to be of maternal origin.

Genetics of endometriosis: heritability and candidate genes.

Endometriosis is a complex gynecologic disorder that affects as many as 10-15% of premenopausal women. Epidemiologic studies have confirmed that this disease is a genetic disorder of polygenic/multifactorial inheritance. The disorder has long been recognized to show heritable tendencies with recurrence risks of 5-7% for first-degree relatives. The current investigational goal is to determine the number and location of causative genes, a process that has been made possible by recent advances in molecular technology. This chapter discusses heritability studies supporting polygenic/multifactorial inheritance, the scientific basis of genome-wide strategies for identifying causative genes and potential candidate genes.

Genetics of endometriosis.

Endometriosis long has been recognized as showing heritable tendencies, with recurrence risks of 5% to 7% for first-degree relatives. The risk indicates that polygenic and multifactorial etiology is far more likely to be the cause than mendelian inheritance. The current task is to determine the number and location of genes responsible for endometriosis. Molecular advances of the past decade make identification and elucidation of these genes a reality. The authors review the basis for concluding that endometriosis is a genetic disorder of polygenic/multifactorial inheritance. Genome-wide strategies for identifying causative genes are considered and available data on association or linkage to putative candidate genes systematically reviewed.