An effect of glycoprotein IIb/IIIa inhibitors on the kinetics of red blood cells aggregation.

The reversible aggregation of red blood cells (RBCs) continues to be of the basic science and clinical interest. Recently it has been reported about a specific binding between fibrinogen and unknown erythrocyte glycoprotein receptors. The aim of this study was to investigate whether the red blood cell aggregation (RBCA) include the cell-cell interaction using the membrane receptors that bind such ligands as fibrinogen or fibronectin. To test this hypothesis the RBCs were incubated with monafram - the drug of the monoclonal antibodies against glycoprotein (GP) IIb/IIIa, with the GPIIb-IIIa receptor antagonist tirofiban, epifibatide and with the fibrinogen inhibiting peptide. It has been found that the RBC incubation with monafram resulted in a marked RBCA decrease mainly in persons with high level of aggregation. Another research session has shown that RBC incubation with fibronectin was accompanied by a significant RBCA rise. The monafram addition to red cell incubation medium resulted in a significant RBCA lowering. The cell incubation with tirofiban and epifibatide issued in RBCA decrease. The similar results were obtained when RBCs were incubated with the fibrinogen inhibiting peptide. Although monafram, tirofiban, eptifibatide and the fibrinogen inhibiting peptide were related to fibrinogen function they didn't inhibit RBCA completely. Therefore, under moderate and low red blood cell aggregation the cell binding is probably related to nonspecific mode. It seems evident that the specific and nonspecific modes of red blood cell aggregate formation could co-exist. Additional theoretical and experimental investigations in this area are needed.

Normal and system lupus erythematosus red blood cell interactions studied by double trap optical tweezers: direct measurements of aggregation forces.

Direct measurements of aggregation forces in piconewton range between two red blood cells in pair rouleau are performed under physiological conditions using double trap optical tweezers. Aggregation and disaggregation properties of healthy and pathologic (system lupus erythematosis) blood samples are analyzed. Strong difference in aggregation speed and behavior is revealed using the offered method which is proposed to be a promising tool for SLE monitoring at single cell level.

Analysis of genetic copy number changes in cervical disease progression.

BACKGROUND: Cervical dysplasia and tumorigenesis have been linked with numerous chromosomal aberrations. The goal of this study was to evaluate 35 genomic regions associated with cervical disease and to select those which were found to have the highest frequency of aberration for use as probes in fluorescent in-situ hybridization. METHODS: The frequency of gains and losses using fluorescence in-situ hybridization were assessed in these 35 regions on 30 paraffin-embedded cervical biopsy specimens. Based on this assessment, 6 candidate fluorescently labeled probes (8q24, Xp22, 20q13, 3p14, 3q26, CEP15) were selected for additional testing on a set of 106 cervical biopsy specimens diagnosed as Normal, CIN1, CIN2, CIN3, and SCC. The data were analyzed on the basis of signal mean, % change of signal mean between histological categories, and % positivity. RESULTS: The study revealed that the chromosomal regions with the highest frequency of copy number gains and highest combined sensitivity and specificity in high-grade cervical disease were 8q24 and 3q26. The cytological application of these two probes was then evaluated on 118 ThinPrep samples diagnosed as Normal, ASCUS, LSIL, HSIL and Cancer to determine utility as a tool for less invasive screening. Using gains of either 8q24 or 3q26 as a positivity criterion yielded specificity (Normal +LSIL+ASCUS) of 81.0% and sensitivity (HSIL+Cancer) of 92.3% based on a threshold of 4 positive cells. CONCLUSIONS: The application of a FISH assay comprised of chromosomal probes 8q24 and 3q26 to cervical cytology specimens confirms the positive correlation between increasing dysplasia and copy gains and shows promise as a marker in cervical disease progression.

Assessment of fluorescence in situ hybridization and hybrid capture 2 analyses of cervical cytology specimens diagnosed as low grade squamous intraepithelial lesion for the detection of high grade cervical intraepithelial neoplasia.

OBJECTIVE: To assess Hybrid Capture 2 (HC2) and fluorescence in situ hybridization (FISH) for the detection of cervical intraepithelial neoplasia 2 or worse (CIN 2+) in patients with a cytologic diagnosis of low grade squamous intraepithelial lesion (LSIL). STUDY DESIGN: Residual samples from 115 LSIL-diagnosed cervical cytology specimens were evaluated by high-risk human papillomavirus (HR-HPV) HC2 testing and FISH using biotin-labeled probes to HR-HPV and chromosomal probes to 3q26 (TERC) and 8q24 (CMYC). A cervical biopsy diagnosis of CIN 2+ was considered as evidence of high grade disease. RESULTS: The positive and negative predictive values of HC2 and FISH for detecting patients with CIN 2+ were 32% vs. 37% and 100% vs. 93%, respectively. The sensitivities of HC2 and FISH for CIN 2+ were not significantly different (100% vs. 90%, p = 0.25), while the specificity of HC2 was significantly lower than that of FISH (28% vs. 48%, p=0.003). FISH diagnosed fewer specimens as positive as compared to HC2 (62% vs. 79%). CONCLUSION: These preliminary data suggest that FISH testing may be useful for determining which patients with LSIL are most likely to have CIN 2+ on clinical follow-up.

Dysplastic cells in cytological cervical samples show a high incidence of chromosomal abnormalities.

Chromosomal abnormalities are frequent in most cervical cancers. Amplifications of both the 3q26 (TERC) and 8q24 (MYC) loci have been shown to be prevalent in both high-grade lesions and invasive cervical carcinoma. Most of these studies have looked at either the histological sample or at the entire cytological population of cells. We have developed a Papanicolaou (Pap) destaining method that allows for the accurate analysis of individual cells that were previously identified by cytopathology as dysplastic. The application of fluorescence in situ hybridization (FISH) was then implemented to determine the chromosomal status of the dysplastic cells in the samples and correlate the two events. Chromosomal abnormality is over a thousand times more frequent in dysplastic cells compared with their morphologically normal counterparts.

Comparison of fluorescence in situ hybridization, hybrid capture 2 and polymerase chain reaction for the detection of high-risk human papillomavirus in cervical cytology specimens.

OBJECTIVE: To compare a recently developed fluorescence in situ hybridization (FISH) high-risk human papillomavirus (HR-HPV) assay to Hybrid Capture 2 (HC2) (Digene Corporation, Gaithersburg, Maryland, U.S.A.) and polymerase chain reaction (PCR) for the detection of HR-HPV subtypes in cervical cytology specimens. STUDY DESIGN: One hundred forty-one liquid-based cytology specimens were used to produce a thin-layer slide for FISH analysis. The remaining material was sent for HC2 and PCR HR-HPV testing. Thin-layer slides were hybridized with a FISH probe set containing a biotin-labeled HR-HPV cocktail and were manually screened for HR-HPV-infected cells. Specimens with > or = 1 HPV-positive cell by FISH were considered positive for HR-HPV infection. RESULTS: There was complete concordance between HC2, FISH and PCR in 104 (75%) specimens. FISH was concordant with HC2 and PCR in 120 (85%) and 115 (82%) specimens, respectively. HC2 and PCR were concordant in 118 (84%) specimens. CONCLUSION: The concordance of HR-HPV detection between FISH and HC2/PCR appears similar to concordances between HC2 and PCR. This suggests that FISH may be another method of detecting HR-HPV while having the potential to add additional information such as integrated/episomal staining and the ability to detect chromosomal abnormalities in individual cells.

Chromosomal abnormalities in non-small cell lung carcinomas and in bronchial epithelia of high-risk smokers detected by multi-target interphase fluorescence in situ hybridization.

Human lung carcinogenesis is accompanied by complex chromosomal changes that may be detected in interphase cells by fluorescence in situ hybridization (FISH) assay using recently developed multitarget DNA probes. Touch preparations of 20 non-small cell lung carcinomas, sputum specimens from 3 patients with lung cancer and from 11 ex-smokers without lung cancer, and cultured benign bronchial epithelium of 42 high-risk smokers, 9 of whom had concurrent invasive carcinoma, were tested using a four-color FISH probe (LAVysion) targeting centromere 6, 5p15.2, 7p12 (EGFR), and 8q24 (MYC). Significantly high frequencies of abnormal cells were found in each of the 20 NSCLC (100%) and in the 3 sputum specimens from lung cancer patients. None of the cytologically normal sputa contained FISH abnormalities. Cultured bronchial epithelial cells from 11 of 42 patients (26%) were abnormal for at least one probe. Abnormal FISH patterns had no association with gender, presence of tumor or histology. Multicolor FISH can readily detect chromosomal abnormalities in imprints and sputa from lung carcinomas. Chromosomal aneusomy is also frequent in bronchial epithelial cells from long-term smokers. The prognostic significance of the multicolor LAVysion FISH probe set should be validated in a controlled clinical trial.

A fluorescence in situ hybridization-based assay for improved detection of lung cancer cells in bronchial washing specimens.

BACKGROUND: Interphase fluorescence in situ hybridization (FISH) is a powerful tool for detecting chromosome and locus-specific changes in tumor cells. We developed a FISH-based assay to detect genetic changes in bronchial washing specimens of lung carcinoma patients. METHODS: The assay uses a mixture of fluorescently labeled probes to the centromeric region of chromosome 1 and to the 5p15, 8q24 (site of the c-myc gene), and 7p12 (site of the EGFR gene) loci to assess cells in bronchial washing specimens for chromosomal abnormalities indicative of lung carcinoma. The FISH assay was performed on 74 specimens that had been assessed previously for evidence of malignancy by routine cytology with Pap staining. RESULTS: Forty-eight patients had histologically confirmed lung carcinoma and 26 patients had a clinical diagnosis that was negative for lung carcinoma. FISH analysis was performed without knowledge of the patient's clinical information. The finding of six or more epithelial cells with gains of two or more chromosome regions was considered a positive FISH result (i.e., evidence of malignancy). The sensitivity of FISH for the detection of lung carcinoma was 82% in this set of specimens compared with a 54% sensitivity by design for cytology (FISH vs. cytology, P = 0.007). FISH detected 15 of 18 specimens that were falsely negative by cytology. The specificities of FISH and cytology were 82% and 100%, respectively, and were not significantly different (P = 0.993). CONCLUSIONS: The data indicate a potential utility of the FISH assay as an adjunct to bronchial washing cytology in routine clinical practice.

A comparison of BTA stat, hemoglobin dipstick, telomerase and Vysis UroVysion assays for the detection of urothelial carcinoma in urine.

PURPOSE: We determine the sensitivity and specificity of various assays for the detection of urothelial carcinoma. MATERIALS AND METHODS: A total of 280 voided urine specimens from 265 patients were obtained immediately before cystoscopy for BTA stat, (Bard Diagnostic, Redmond, Washington) hemoglobin dipstick, (Bayer, Elkhart, Indiana) telomerase and UroVysion (Vysis, a wholly owned subsidiary of Abbott Laboratories, Abbott Park, Illinois) analysis. RESULTS: Of the 265 patients 75 had biopsy proven urothelial carcinoma, and the sensitivity of the assays was determined from these patients. From most sensitive to least sensitive, the overall sensitivity of UroVysion (73 cases), BTA stat (72), hemoglobin dipstick (73) and telomerase (70) was 81%, 78%, 74%, and 46%, respectively. Each of the first 3 tests was statistically significantly more sensitive than the telomerase assay (p <0.05). However, the differences in overall sensitivity of UroVysion, BTA stat and hemoglobin dipstick were not statistically significant. The specificity of the tests was calculated for 80 of the 265 patients in this study who had no history of urothelial carcinoma and negative cystoscopy findings despite common urological complaints. From most specific to least specific, the specificity of UroVysion, telomerase, BTA stat and hemoglobin dipstick was 96%, 91%, 74% and 51%, respectively. UroVysion and telomerase were statistically significantly (p <0.01) more specific than the BTA stat and hemoglobin dipstick assays, and all of the assays were more specific than hemoglobin dipstick testing (p <0.001). CONCLUSIONS: Our study reveals that UroVysion is the most sensitive and specific assay among those tested for the detection of urothelial carcinoma. Telomerase testing had good specificity but poor sensitivity. The BTA stat and hemoglobin dipstick tests had good sensitivity but relatively poor specificity. UroVysion is a promising new assay for the detection of urothelial carcinoma in urine specimens. However, further studies are needed to explore the role of the various assays in the treatment of patients with superficial urothelial carcinoma.