Fetal DNA in maternal circulation of first-trimester spontaneous abortions.

OBJECTIVE: To establish whether fetal DNA can be identified in the maternal circulation in first-trimester spontaneous abortions. METHODS: Women with confirmed spontaneous abortions and no histories of previous pregnancy were recruited. Peripheral venous blood samples were obtained and DNA extracted. Real-time quantitative polymerase chain reaction was done using SRY and beta-actin systems for calculating fetal and total DNA, respectively. RESULTS: Of 25 women, SRY-specific signals were detected in 11 indicating that the abortions were male. The remaining 14 were negative for the SRY gene. Women with positive results were of similar gestational age to those who were negative (mean 68.4 and 69.0 days). Fetal:total DNA ratio was calculated for positive samples and ranged from 15.8 to 360.1 x 10(+3). Mean ratio was 99.4 x 10(+3) and median was 67.5 x 10(+3). CONCLUSION: Fetal DNA is present in the maternal circulation of first-trimester spontaneous abortions.

Improved in situ detection method for telomeric tandem repeats in metaphase spreads and interphase nuclei.

Peptide nucleic acid technology (PNA) has become an extremely useful tool and promises to impact on molecular biology and diagnostics. These synthetic DNA analogues pair with DNA and RNA molecules according to Watson and Crick base pairing rules. This paper describes a sensitive and quick fluorescent in situ hybridisation (ISH) technique to determine DNA telomere repeat sequences (TTA GGG)n using epifluorescence microscopy. Telomeres are special, repeated structures at the end of each eukaryotic chromosome and serve as protective caps to prevent DNA rearrangements and fusion of chromosomes. A model system has been developed, using stimulated peripheral blood lymphocytes, which facilitates simultaneous detection of telomeres in metaphase as well as in interphase nuclei. A fluorescein isothiocyanate labelled PNA probe (18 mer) directed against complementary telomeric sequences at the end of each chromosome is used. In addition, a simple, easy to perform PNA-ISH protocol is described that overcomes common hybridisation problems encountered using DNA and RNA oligoprobes. Furthermore, the usefulness of a chromogenic immunocytochemical detection system is shown for PNA-ISH.

Estradiol, gonadotropins, and tumor markers in ovarian cyst fluid.

BACKGROUND: The study was designed to improve the discrimination between functional and neoplastic ovarian cysts in order to avoid unnecessary surgery. METHODS: Concentrations of tumor markers (CA 125, CEA, CASA, CA 72-4) and hormones (estradiol, FSH, LH) in cyst fluid were detected by enzyme immuno- or immunoradiometric assays. Wilcoxon test was used to evaluate the correlation of cyst fluid markers and histology. RESULTS: One hundred and thirty-eight ovarian cyst aspirates were investigated. Seventy-one patients (51.5%) had functional cysts whereas 67 (48.5%) had benign (n=59) or malignant (n=8) cystic tumors. Statistically significant correlations of CA 125 (p<0.0005) and CASA (p<0.02) with neoplastic histology were found. No significant correlation could be detected between CA 72-4, CEA, or hormone values and histology. Elevated estradiol concentrations are suspicious for functional cysts in premenopausal age. Low FSH and LH levels seem to be an indicator for functional cysts in peri- and postmenopausal age. CONCLUSIONS: The assessed analytes could not reliably distinguish between functional and neoplastic ovarian cysts. Our results indicate that CA 125 is a marker for neoplastic histology in a proportion of ovarian cysts. The use of FSH and LH in the diagnosis of postmenopausal blastomas needs further investigation.

Epidermal growth factor receptor gene and c-erbB-2 gene amplification in ovarian cyst fluid.

OBJECTIVE: To test for a significant difference between functional and neoplastic ovarian cyst with respect to epidermal growth factor (EGF) receptor and c-erbB-2 proto-oncogene amplification rates. METHODS: We determined amplification of EGF-receptor and c-erbB-2 genes by differential polymerase chain reaction (PCR) on 138 ovarian-cyst aspirates. The semiquantitative differential PCR is based on simultaneous co-amplification of a target gene and a reference gene. Amplification rates were detected by densitometry of silver-stained polyacrylamide gels and were scored as single-, low-, or high-copy numbers. Wilcoxon ranked sum test, Pearson correlation coefficient, and multiple logistic regression were used to evaluate the differences in oncogene amplification and to predict histology. RESULTS: There were 71 (51.5%) women with functional cysts, whereas 67 (48.5%) had benign (n = 59) or malignant (n = 8) tumors. Low-copy (two- to fourfold copy numbers) EGF-receptor gene amplification was found in 22 of 67 (33%) women with neoplastic cysts, but in only eight (11%) of those with functional cysts. Neoplastic histology differed significantly from functional histology in correlation to EGF-receptor low-copy gene amplification (r = .279, P < .001). There was no significant difference in c-erbB-2 gene amplification with respect to functional and neoplastic histology (r = .083, P = .32). CONCLUSIONS: Low-copy EGF-receptor gene amplification seems to be a market for neoplastic histology. Epidermal growth factor receptor gene amplification may be involved in proliferation and growth in an early stage of tumorigenesis. However, further studies are required to investigate this gene structure abnormality on a gene function level. Amplification of c-erbB-2 proto-oncogene does not appear to be a common factor in the development of ovarian tumors.