Biomarkers of abnormally invasive placenta.

INTRODUCTION: Abnormally invasive placenta (AIP, aka placenta accreta spectrum; PAS) is an increasingly common pregnancy pathology, which, despite significant morbidity risk to the mother, is often undiagnosed prior to delivery. We tested several potential biomarkers in plasma from PAS mothers to determine whether any were sufficiently robust for a formal, diagnostic accuracy study. METHODS: We examined hyperglycosylated hCG (h-hCG), decorin and IL-8, based on biological plausibility and literature indications that they might be altered in PAS. These analytes were assayed by ELISA in maternal plasma from five groups, comprising (1) normal term controls, (2) placenta previa controls, and cases of (3) placenta increta/percreta without placenta previa, (4) placenta previa increta/percreta and (5) placenta previa accreta. RESULTS: There were no differences in h-hCG, ß-hCG or the h-hCG/ß-hCG ratio between the groups. Mean decorin levels were increased in previa controls (Group 2) compared to the other groups, but there was substantial overlap between the individual values. While an initial multiplex assay showed a greater value for IL-8 in the placenta previa increta/percreta group (Group 4) compared to placenta previa controls (Group 2), the subsequent validation ELISA for IL-8 showed no differences between the groups. DISCUSSION: We conclude that the absence of differences and the extent of overlap between cases and controls does not justify further assessment of these biomarkers.

Suppressor of cytokine signaling 3 expression in anaplastic large cell lymphoma.

Using a cDNA microarray, we found that suppressor of cytokine signaling 3 (SOCS3) is highly expressed in anaplastic lymphoma kinase (ALK)+ anaplastic large cell lymphoma (ALCL) cell lines. As SOCS3 is induced by activated signal transducer and activator of transcription 3 (STAT3), and ALK activates STAT3, we hypothesized that SOCS3 may play a role in ALK+ ALCL pathogenesis via the Janus kinase 3 (JAK3)-STAT3 pathway. Using ALCL cell lines, we show by coimmunoprecipitation experiments that SOCS3 physically binds with JAK3 in vitro, and that JAK3 inhibition by WHI-P154 downregulates SOCS3 expression. Western blot analysis confirmed expression of SOCS3 and also showed coexpression of phosphorylated (activated) STAT3 (pSTAT3). Direct sequencing of the SOCS3 gene showed no mutations or alternative splicing. In ALCL tumors that were assessed by immunohistochemistry, nine of 12 (75%) ALK+ tumors were SOCS3 positive and eight (67%) coexpressed pSTAT3. In comparison, 18 of 25 (72%) ALK-- tumors were SOCS3 positive and seven (28%) coexpressed pSTAT3. These results show that SOCS3 is overexpressed in ALCL, attributable to JAK3-STAT3 activation and likely related to ALK in ALK+ tumors. However, SOCS3 is also expressed in tumors that lack STAT3 and ALK suggesting alternative mechanisms of upregulation.

Establishment of a human cell line (SKI-DLCL-1) with a t(1;14)(q21;q32) translocation from the ascites of a patient with diffuse large cell lymphoma.

Cytogenetic abnormalities at chromosome 1q21 are among the most common second genetic events observed in Non-Hodgkin's Lymphomas and have prognostic significance. Recently, BCL9 has been cloned from a pre-B-cell lymphoblastic leukemia cell line, which carried a t(1:14)(q21;q32). However, among a panel of 39 B-cell malignancies with 1q21 translocation, only two cases showed rearrangement for the BCL9 gene. We report the establishment of a new lymphoma cell line from a patient with relapsed diffuse large cell lymphoma. This cell line SKI-DLCL-1 showed cell surface antigens identical to the original tumor and demonstrated the profile of a mature B-cell phenotype: CD19 and CD20 positive, CD5 and C10 negative. It carried a t(1;14)(q21;q32) translocation identical to the original tumor. Although the clinical presentation was an isolated effusion lymphoma, studies for HIV-1, HHV8 and EBV were all negative. Southern blot analysis demonstrated that BCL9 was not rearranged in the SKI-DLCL-1 cell line. In addition, the BCL9 gene was not over-expressed in SKI-DLCL-1 cell line. The identification of a new locus at 1q21 will help clarify the pathogenesis of B-cell malignancies with a translocation involving this locus.

A novel gene STORP (STOmatin-Related Protein) is localized 2 kb upstream of the promyelocytic gene on chromosome 15q22.

We generated a 100-kb map of the region 5' of the PML (promyelocytic leukemia) gene on human chromosome 15q22 and identified a new gene provisionally named STORP for stomatin-related protein. The STORP gene is positioned 2 kb upstream of the PML gene in a head-to-head configuration, and contains 7 exons spanning a genomic region of about 11 kb. There is an open reading frame of 398 amino acids, which would encode a protein of 45 kD. Northern blot analysis demonstrated that the STORP gene has a ubiquitous pattern of expression similar to that of the PML gene. Hybridization of STORP cDNA probe to genomic DNA from other species demonstrated that the STORP gene is conserved among mammalian vertebrates and that the physical linkage with PML is conserved in mice. Unlike PML, the STORP gene is not induced by interferon alpha (IFNalpha), and thus can be distinctly regulated from the PML gene. STORP is homologous to the EPB72 gene coding for the erythrocyte band 7 integral membrane protein or stomatin, which is deficient in a certain form of hereditary stomatocytosis. The function of STORP is unknown. Further study will focus on studying its potential role in red cell function and disorders.

MUC1 dysregulation as the consequence of a t(1;14)(q21;q32) translocation in an extranodal lymphoma.

Cytogenetic abnormalities at chromosome 1q21 are among the most common lesions in diffuse large-cell lymphoma and have been associated with a poor prognosis. A novel cell line, SKI-DLCL-1, was established from ascitic fluid that carries a t(1;14)(q21;q32) chromosomal translocation. Using pulsed-field gel electrophoresis, the breakpoint on the IgH locus mapped to a gamma locus between Calpha(1) and Calpha(2). A cosmid library was prepared from SKI-DLCL-1, and Cgamma-positive clones spanning the breakpoint were identified by screening with fluorescence in situ hybridization. The breakpoint occurs 860 bp downstream of the 3' UTR of the MUC1 gene. The break appears to be a staggered double-strand break consistent with an error in immunoglobulin class switching. The MUC1 gene is highly transcribed and translated, and the protein is highly glycosylated. It is postulated that MUC1 expression is brought under the control of the 3'Ealpha enhancer. MUC1 lies in a region of chromosome 1 characterized by an unusually high density of genes, with 7 known genes in a region of approximately 85 kb. To determine whether there was a pleiotropic effect of the expression of genes in the region as a consequence of the translocation, the expression of 6 additional genes was assessed. None of the other genes in this region (CLK2, propin, COTE1, GBA, metaxin, and thrombospondin 3) are overexpressed in SKI-DLCL-1. Thus, the translocation t(1;14)(q21;q32) seen in both the primary tumor and the derived cell line results in the marked overexpression of MUC1 without affecting the expression of other genes in the region. (Blood. 2000;95:2930-2936)

Physical linkage of the lysyl oxidase-like (LOXL1) gene to the PML gene on human chromosome 15q22.

A contig was constructed centered on the PML (promyelocytic leukemia) gene. Using an exon-trapping approach to identify potential genes from a pool of cosmids located 5' of the PML gene, four exons were identified that showed 100% sequence homology with the previously cloned lysyl oxidase-like (LOXL1) gene. An exon probe identified a single transcript of 2.4 kb on a multitissue Northern blot with a pattern identical to the one reported for the LOXL1 gene. Pulsed-field gel electrophoresis showed comigrating bands for both the PML cDNA and LOXL1 probes, demonstrating a physical linkage between these two genes. These data provide physical mapping information to complement the previous cytogenetic localization of LOXL1.

Cloning and characterization of a Golgin-related gene from the large-scale polymorphism linked to the PML gene.

Megabase-scale mapping of the PML gene locus revealed the presence of a large-scale insertion-deletion polymorphism located 25 kb downstream of the PML gene. The polymorphism is organized as a head-to-tail tandem 25-kb repeat containing one to five units. Characterization of the first repeat unit downstream of PML revealed the presence of a gene with strong homology to a family of Golgin-related proteins. The gene, designated GLP (for Golgin linked to PML), is strongly expressed as a 6-kb transcript in normal human testis. In situ hybridization of normal human testis demonstrated that the expression of GLP was restricted to late meiotic germ cells. There was weak expression in late pachytene spermatocytes and strong expression in spermatids. GLP is 50% homologous to other Golgin-related proteins including the vesicle docking protein GM130. Southern blot hybridization of genomic DNA with a GLP probe demonstrated numerous homologous bands outside the PML locus. Three of these loci have been mapped by fluorescence in situ hybridization to chromosome loci 9q34.1, 15q11-q13, and 15q22-q24. Hybridization of a GLP cDNA probe to a zoo blot demonstrated multiple signals in nonhuman primates but not in other species and suggested the duplication of an ancestral locus around 20 million years ago.