MBL is an aggressive NHL with unique clinicopathologic aspects, often refractory to current CHT designed for high-grade NHL. Poor performance status and pericardial effusion predict NR and poor survival. Inadequate response after the first courses of front-line CHT predicts failure of subsequent treatment. Responders with bulky mediastinum or residual mediastinal abnormality after CHT are at risk of relapse. These factors should help to select high-risk patients for intensive treatments.

We have compared CDlO antigen expression in normal fetal bone marrow with that of B-lineage acute lymphoblastic leukemia (ALL). Both quantitative indirect immunofluoresence (QIFI) and direct immunofluorescence (IF) tests with Quantum beads were used to convert median fluorescence intensity (MFI) values into numbers of antigen molecules expressed per cell (AgE). Lymphoid precursors in the fetal marrow and liver expressed 3-12.5 x lo3 CD10 molecules/cell with an upper limit of 5 x 104/cell (MaxAgE). The median CDlO AgE in the different cases of acute B-lineage ALL were variable and ranged from undetectable to very high values (> 1.8 x lo5). In 24 of the 72 cases (33%) tested with QlFl the median CDlO AgE was above the highest values seen in normal samples (> 5 x 104/cell). An additional 23.6% of cases had higher median values than the normal median C D l O AgE. Next, CDlO antigen was quantitated in 78 cases during the routine multiparameter analysis of 8-lineage leukemia using CD1 O/class ll/CD34 3-color IF test or CDlO/TdT 2-color IF test. The aberrant overexpression was confirmed in 43.6% of ALL cases. The CDIObright display suggested ALL diagnosis even when few cells were available for study, e.g., in early relapse and in ALL masquerading as aplastic anemia. The levels of CDlO expression were maintained in relapse. In addition, different C D l O levels were associated with the various chromosomal alterations: high C D l O levels (> 3 x 104/cell) with hyperdiploidy, low CDlO levels ( 1 . 8 4 x 103/cell) with the t(1;191, and undetectable levels (< 1.2 x 103/cell) with the t(4;11) translocations. These findings show that while all these diseases are part of the precursor B-cell spectrum, the CDlO changes are linked to disease-associated alterations instead of truly reflecting the features of subtypes of normal B-cell precursors. The quantitative CDlO assessment should therefore be part of the routine flow cytometric assessment in ALL, and further careful studies are warranted during the regeneration phase following chemotherapy. High CDlO expression alone during strong bone marrow regeneration may not be leukemia specific and both the multiparameter analysis described above and parallel studies for gene rearrangements will be necessary to establish the relative values of these assays in detecting minimal disease amidst regenerating marrow. 0 1994 Wiley-Liss, Inc.Key terms: CD10, acute lymphoblastic leukemia, minimal residual disease, immunodiagnosis, flow cytometry, quantimetrySince the discovery of B precursor cell-associated molecules such as common acute lymphoblastic leukemia (ALL) antigen (referred to as CDlO and neutral endopeptidase) (1,2), CD34 antigen (3-5), and nuclear terminal transferase ( TdT) ( 1,6) it has been emphasized that these differentiation antigens are expressed on normal immature cells and retained on the corresponding malignancies. At the same time, the strikingly high expression of CDlO antigen on occasional cases of ALL has been recorded on the microscope (6) or by flow cytometry (7) bu...

BACKGROUND Proteasomes are nonlysosomal proteolytic structures that have been implicated in cell growth and differentiation. Abnormal expression levels of proteasomes have been described in tumor cells, and proteasomes can be detected and measured in plasma. The objective of this study was to characterize differences in proteasome levels between normal, healthy donors and patients with neoplastic disease and to correlate the findings with clinical status and other biologic markers of disease spread. METHODS Plasma proteasome levels were measured using a sandwich enzyme‐linked immunosorbent assay in normal donors (n = 73 donors) and in patients with solid tumors (n = 20 patients), acute leukemia (n = 35 patients), myeloproliferative (n = 37 patients) and myelodysplastic (n = 19 patients) syndromes, chronic lymphocytic leukemia (n = 44 patients), non‐Hodgkin lymphoma (n =104 patients), Hodgkin disease (n = 14 patients), other lymphoid disorders (n = 17 patients), and multiple myeloma (n = 27 patients). RESULTS In the normal donors, the plasma proteasome concentration was 2356 ng/mL ± 127 ng/mL. Patients with solid tumors exhibited a significantly higher value (7589 ng/mL ± 2124 ng/mL), similar to the patients with myeloproliferative (4099 ng/mL ± 498 ng/mL) and myelodysplastic (2922 ng/mL ± 322 ng/mL) syndromes. Patients with lymphoproliferative disorders, in contrast, had significantly lower values than normal donors (1751 ng/mL ± 107 ng/mL), except those in aggressive phase of the disease. This low level persisted in patients who were in complete remission. Proteasome levels decreased during the initial phase of treatment. Although there was a significant correlation with serum lactic dehydrogenase levels, frequent discrepancies were noted. There was no correlation with C‐reactive protein or β2‐microglobulin levels, even in the group of patients with multiple myeloma. CONCLUSIONS The plasma proteasome level is a potential new tool for the monitoring of patients with neoplastic disease. It is not correlated solely with cell lysis and may be involved in the pathophysiology of disease progression. Cancer 2001;92:2493–500. © 2001 American Cancer Society.

Simplified culture conditions are essential for large-scale drug screening and medical applications of human pluripotent stem cells (hPSCs). However, hPSCs [ie, human embryonic stem cells (hESCs), and human induced pluripotent stem cells (iPSCs) are prone to genomic instability, a phenomenon that is highly influenced by the culture conditions. Enzymatic dissociation, a cornerstone of large-scale hPSC culture systems, has been reported to be deleterious, but the extent and the timeline of the genomic alterations induced by this passaging technique are still unclear. We prospectively monitored three hESC lines that were initially derived and cultured on human feeders and passaged mechanically before switching to enzymatic single-cell passaging. We show that karyotype abnormalities and copy number variations are not restricted to long-term culture, but can occur very rapidly, within five passages after switching hESCs to enzymatic dissociation. Subchromosomal abnormalities preceded or accompanied karyotype abnormalities and were associated with increased occurrence of DNA double-strand breaks. Our results indicate that enzymatic single-cell passaging can be highly deleterious to the hPSC genome, even when used only for a limited period of time. Moreover, hPSC culture techniques should be reappraised by complementing the routine karyotype analysis with more sensitive techniques, such as microarrays, to detect subchromosomal abnormalities.

LncRNAs are emerging potential key players in gene expression regulation. Analysis of RNA-seq data from human pre-implantation embryos identified lncRNA signatures that are specific to this critical step. We anticipate that further studies will show that these new transcripts are major regulators of embryo development. These findings might also be used to develop new tests/treatments for improving the pregnancy success rate in IVF procedures or for regenerative medicine applications involving PSC.