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Objective Conventional chromosomal studies or fluorescent in situ hybridization takes days to diagnose fetal aneuploidies during amniocentesis. Here, we evaluated the value of mass spectrometry-based clinical proteomics analysis on amniotic fluid supernatant (AFS) as a rapid detection of fetal aneuploidies. Methods Proteomics profiles generated by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) after fractionating samples with functionalized magnetic beads were used for differentiating 60 normal karyotypic from 20 aneuploid AFS. After the discriminating models were generated using genetic algorithm, we evaluated the clinical efficacy of the models in detecting aneuploidies in two batches (each n = 30) of AFS prior to the release of chromosomal diagnoses. Results Within hours, the two-step proteomics analysis of AFS with the C18 model, followed by the weak cation exchange model, was able to detect aneuploid AFS at 3.3% disease prevalence rate with 100% sensitivity, 72 to 96% specificity, 11 to 50% positive predictive value, and 100% negative predictive value. Conclusion Clinical proteomics analysis of AFS using magnetic beads-based sample preparation and MALDI-TOF-MS can be used as a rapid detection for fetal aneuploidies. With perfect sensitivity and negative predictive value of the two-step proteomics method, it may be used for rapid detection of aneuploid AFS immediately after amniocentesis. Further large-scale examinations are apparently needed to verify the clinical value of this rapid detection. Copyright © 2005 John Wiley & Sons, Ltd.

BACKGROUND Compelling evidence indicates that paclitaxel kills cancer cells through the induction of apoptosis. Paclitaxel binds microtubules and causes kinetic suppression (stabilization) of microtubule dynamics. The consequent arrest of the cell cycle at mitotic phase has been considered to be the cause of paclitaxel-induced cytotoxicity. However, the biochemical events, downstream from paclitaxel's binding to microtubules, that lead to apoptosis are not well understood. METHODS The authors examined recent scientific literature about the mechanisms by which paclitaxel exerts cytotoxicity. RESULTS In addition to an arrest of the cell cycle at the mitotic phase in paclitaxel-treated cells, recent discoveries of activation of signaling molecules by paclitaxel and paclitaxel-induced transcriptional activation of various genes indicate that paclitaxel initiates apoptosis through multiple mechanisms. The checkpoint of mitotic spindle assembly, aberrant activation of cyclin-dependent kinases, and the c-Jun N-terminal kinase/stress-activated protein kinase (JNK/SAPK) are shown to be involved in paclitaxel-induced apoptosis. Consistent with observations that microtubules of different status (e.g., cytoskeletal microtubules vs. mitotic spindles) have different sensitivity to paclitaxel, the concentration of paclitaxel appears to be the major determinant of its apoptogenic mechanisms. CONCLUSIONS Advances in research of the cell cycle and apoptosis have extended our understanding of the mechanisms of paclitaxel-induced cell death. Further elucidation of resistance and enhancement of paclitaxel-induced apoptosis should expedite the development of better paclitaxel-based regimens for cancer therapy. Cancer 2000;88:2619–28. © 2000 American Cancer Society.

Objective To investigate circulating levels of insulin-like growth factor-binding protein 1 (IGFBP-1) and IGFBP-3 in the mother and the fetus in pregnancies complicated by pre-eclampsia, and the relationship between serum levels of IGFBPs and fetal birthweight. Design A prospective study over an 18 month period. Setting A tertiary care academic medical centre. Participants Sixty-six pregnant women with pre-eclampsia (35 cases of mild/moderate pre-eclampsia and 31 cases of severe pre-eclampsia) and 78 nonpra-eclamptic pregnant women of matched gestational weeks and maternal ages. Main outcome measures Serum concentrations of IGFBP-1 and IGFBP-3 at the time of delivery. Results In pre-eclampsia associated with intrauterine growth retardation (IUGR), maternal and cord serum IGFBP-1 levels at the time of delivery were elevated. By contrast, circulating IGFBP-3 levels in both the mother and the fetus were lower in pre-eclampsia with IUGR than in nonpre-eclamptic pregnancy. However, there was no difference in serum IGFBP-1 and IGFBP-3 levels between pre-eclampsia without IUGR and nonpre-eclamptic pregnancy in both the mother and the fetus. Conclusions In pre-eclampsia, elevated concentrations of circulating IGFBP-1 and decreased serum IGFBP-3 levels were observed in both the mother and the fetus. However, these changes may simply reflect low birthweight in pre-eclampsia.