Expression of receptor tyrosine kinase Ror1 in a wide variety of
May 8, 2019
Expression of receptor tyrosine kinase Ror1 in a wide variety of cancers has emerged as a new era focusing on targeting this receptor in cancer therapy. showed that this construct could express Ror1-ECD at protein level and also the protein could effectively translocate to the surface of transfected cells. Such model may suggest that a proportion of Ror1 molecules expressed by tumor cells are not full-length Ror1. This notion may be considered when applying flow cytometry using antibodies against Ror1 for screening of tumor cells in order to avoid any miscalculation in the number of Ror1 molecules expressed by tumor cells. Furthermore, such expression may bring about assumptions on functional roles of Ror1-ECD in tumorigenesis, which requires extensive functional studies. (10C12). Others and we have recently reported expression of Ror1 in a variety of malignancies including acute lymphoblastic leukemia, Chronic Lymphocytic Leukemia (CLL), mantle cell lymphoma, marginal zone lymphoma, diffuse large B-cell lymphoma, follicular lymphoma and also renal cancer (13C20). The widespread expression of Ror1 in different malignancies with no expression in normal adult tissues makes it a suitable candidate for targeting the cancer cells. In an attempt to identify possible variants of Ror1, we isolated a transcript variant of Ror1 from blood of a CLL patient encompassing the extracellular and transmembrane domains lacking the kinase domain. Such variant has been reported at transcript level (GenBank Decitabine manufacturer locus NM-001083592) and protein level of 50 band in patients with CLL (11). To understand the functional role of this isomer, we designed a construct containing exons 1-8 of Ror1 and transfected this construct into Chinese Hamster Ovary (CHO, CCL-61, ATCC) cell line. Here we describe establishment of a cell line stably expressing the extracellular part of human Ror1 (Ror1-ECD) localized to cell membrane. Materials and Methods Vector construction Ror1-ECD was PCR amplified using a human full-length cDNA clone EN1031_D08 Ror1 gene (Origene Technologies, MD) as template and primers with appropriate restriction sites. A sense primer was GGTACCGCCACCATGCACCGGC CGCGCCGCCGC with KpnI restriction site plus KOZAK sequences (GCCACC) and an antisense primer was TCTAGACTACTTGGGTTTATATG ATTCAGC with XbaI restriction site plus TAG as a stop codon. PCR was carried out in a 25 reaction [1 of template, 1 of forward and reverse primers (10 dNTPs (10 MgCl2, 2.5 10buffer, and 1 Taq DNA polymerase (Invitrogen, USA)]. The mixture was heated to 95C for 5 and then amplified for 35 cycles: 94C for 30 s, 64C for 30 s and 72C for 1 JM109 (Promega). Plasmid Maxiprep was performed. For transfection the construct was linearized using Decitabine manufacturer of linearized plasmid containing Decitabine manufacturer the Ror1-ECD as well as pCMV6-Neo empty vector were transfected into CHO cells (with 50-70% confluency) using Polyplus transfection-jetPEI (Bioparc, France) according to the manufacturer’s instructions. In transient transfection, proteins were analyzed at 48 after DNA introduction. To establish stable lines, CHO-transfected cells were treated with G418 (850 Tris-HCl, pH=7.2, 150 NaCl and 100 protease inhibitor cocktail (Sigma, MO)]. After 20 Tris-HCl pH=6.8, 10% SDS, 0.5% bromophenol blue and 50% glycerol) was added to the lysate (1:4). Samples were boiled at 100 C for 5 at room temperature with a 0.2 goat anti human Ror1 antibody (R&D Systems, MN). After four times washing, the membranes were incubated with 1:2000 dilution of rabbit anti-goat- HRP conjugate (Dako Cytomation, Denmark). After thorough washing, bands were visualized by ECL reagent (GE Healthcare, Sweden) according to the manufacturer’s instructions and the membranes were exposed to X-ray film. Cell surface flow Rabbit Polyclonal to ARHGEF11 cytometry CHO-transfected and untransfected cells (1×106 goat anti-human Ror1 antibody was added.