Co-presence of a point mutation and a deletion of exon 3 in the glycophorin C gene and concomitant production of a Gerbich-related antibody
TRANSFUSION
Authors: King, MJ; Kosanke, J; Reid, ME; Poole, J; Banks, J; Hemming, NJ; Smythe, J; Martin, PG
Abstract
BACKGROUND: Antigens of the human blood group system Gerbich (Ge) are located on sialoglycoproteins glycophorin C (GPC) and glycophorin D (GPD). CASE REPORT: The Ge+ proposita (RW) produced an alloanti-Ge after receiving 2 units of red cells (RBCs) during surgery. Further studies were carried out to characterize the antibody specificity, RBC GPC and/or GPD (GPC/GPD), and the glycophorin C gene (GYPC) from RW and her compatible siblings. RW's serum contained an alloanti-Ge that did not react with RBCs from RW or four of her siblings or with RBCs with Ge-negative phenotypes. An eluate of RW's antibody reacted weakly with GPC in Western blotting. RW's RBCs were positive with 20 alloanti-Ge2, 1 autoanti-Ge2, 4 alloanti-Ge3, and 1 alloanti-Ge4. Titrations revealed weak expression of these antigens on her RBCs and those of her compatible siblings as compared with controls. in contrast, titrations of mouse and rat monoclonal antibodies specific for GPC/GPD showed no differences. Western blotting of RBC membranes using GPC/GPD specific monoclonal antibodies showed a broad diffuse band corresponding to GPC.Ge in addition to GPC and GPD. Blotting of membranes from trypsin-treated RBCs from these individuals revealed an increase of 1500 in M-r of membrane-bound tryptic fragment over that in the membranes from typsin-treated RBCs from persons with normal GPC/GPD. In RT-PCR, two products were obtained for RW and her compatible siblings: one had a complete deletion of exon 3 and the other had a base change (A-->T) in nucleotide 173 in exon 3 (confirmed by genomic DNA sequencing of exon 3). This point mutation has resulted in the loss of restriction enzyme Tth111 I-sensitive site in the mutant GYPC. CONCLUSION: The specificity of antibody in RW's serum was serologically anti-Ge2. Two genetic events occurred in exon 3 in GYPC of RW and her compatible siblings. The exon 3 deletion confirmed a Ge:-2,-3,4 haplotype. The abnormal tryptic fragment obtained was due to the (A(173)-->T) base change in exon 3 that resulted in Asp(58)-->Val in the deduced amino acid sequence at the membrane boundary.
High Expression of AHSP, EPB42, GYPC and HEMGN Predicts Favorable Prognosis in FLT3-ITD-Negative Acute Myeloid Leukemia
CELLULAR PHYSIOLOGY AND BIOCHEMISTRY
Authors: Zhu, Gang-Zhi; Yang, Yong-Long; Zhang, Yan-Jiao; Liu, Wei; Li, Mu-Peng; Zeng, Wen-Jing; Zhao, Xie-Lan; Chen, Xiao-Ping
Abstract
Background/Aims: Acute myeloid leukemia (AML) is a heterogeneous clonal disease and patients with AML who harbor an FMS-like tyrosine kinase 3 (FLT3) mutation present several dilemmas for the clinician. This study aims to identify novel targets for explaining the dilemmas. Methods: We analyzed four microarray gene expression profiles to investigate changes in whole genome expression associated with FLT3-ITD mutation. Results: We identified 22 differentially expressed genes which are commonly expressed among all four profiles. Kaplan-Meier analysis of the dataset GSE12417 revealed that low expression of AHSP, EPB42, GYPC and HEMGN predicted poor prognosis (AHSP: P=0.0317, HR=1.894; EPB42: P=0.0382, HR=1.859; GYPC: P=0.0015, HR=2.051; HEMGN: P=0.0418, HR=1.838 in GSE12417 test cohort; AHSP: P=0.0279, HR=1.548; EPB42: P=0.0398, HR=1.505; GYPC: P=0.0408, HR=1.501; HEMGN: P=0.0143, HR=1.630 in GSE12417 validation cohort). When patients were FLT3-ITD positive, the expression of FLT3 was significantly increased (all P < 0.05 in four profiles), and correleation analysis of four profiles revealed that the expression of the four candidate genes negatively correlated with FLT3 expression. Conclusions: Our findings suggest that AHSP, EPB42, GYPC and HEMGN may be suitable biomarkers for diagnostic or therapeutic strategies for FLT3-ITD-positive AML patients. (C) 2017 The Author(s) Published by S. Karger AG, Basel