Th rabbit anti-CRKL monoclonal antibody (Y244; Abcam), rabbit anti-phospho CRKL polyclonal antibody (Y207; Cell Signaling, Beverly, MA), or mouse anti-tubulin (2-28-33, Sigma-Aldrich). The immunoreactive proteins were visualized using horseradish peroxidasecoupled secondary antibody and enhanced chemiluminescence detection reagents (GE Healthcare Bio Science) [21].Small interfering RNA (siRNA) knockdownTotal RNA was extracted using Isogen (Nippongene, Tokyo, Japan) or an RNeasy Plus mini kit (Qiagen, Valencia, CA) and converted to cDNA using the SuperScript First-Strand Synthesis System (Invitrogen, Carlsbad, CA). Real-time QRT-PCR was performed using the cDNA and Fast SYBR Green Master Mix (Applied Biosystems, Foster City, CA) on a StepOne Real-Time PCR system (Applied Biosystems). The following PCR primers were used: 5′-CAA CCT GCC TAC AGC AGA AGA TAA-3′ and 5′-CGG CAT CAT TCC CAG GAA-3′ for the CRKL transcript, and 5′-GGT GGT CTC CTC TGA CTT CAA CA-3′ and 5′-GTT GCT GTA GCC AAA TTC GTT GT3′ for the transcript of a housekeeping gene, GAPDH. The relative amounts of CRKL transcript were normalized to those of the GAPDH transcript.Western blot analysisA stealth siRNA duplex oligonucleotide (Invitrogen) was used for siRNA knockdown. The following CRKL sequence was used: 5′-UCG UGA AAG UCA CAA GGA UGA AUA U-3′. A low GC Duplex #2 (Invitrogen) was used as a negative control. MKN74 cells were reversetransfected with the siRNA oligonucleotides (20 nM) using HiPerFect Pyrvinium embonate biological activity Transfection Reagent (Qiagen), according to the manufacturer’s instructions.BMS354825 and AMN107 treatmentCells were lysed, and the protein concentration was quantified using a BCA protein assay kit (Pierce, Rockford, IL).BMS354825, a dual Src/BCR-ABL kinase inhibitor, was kindly provided by Bristol-Myers Squibb (New York, NY), and AMN107, a highly selective BCR-ABL kinase inhibitor, was kindly provided by Novartis Pharmaceuticals (Basel, Switzerland) [22-25]. Stock solutions (10 mM) of BMS354825 and AMN107 were prepared in DMSO. The cells were incubated with BMS354825 or AMN107 at a final concentration of 0.01 to 1.0 M for 72 h. The final concentration of DMSO was set to 0.1 .Natsume et al. Journal of Translational Medicine 2012, 10:97 http://www.translational-medicine.com/content/10/1/Page 5 ofFigure 3 Immunohistochemical detection of CRKL protein in primary gastric cancer. TMA block sections were subjected to an immunohistochemical analysis using anti-CRKL monoclonal antibody (Y243; 1:100 dilution), Histofine Simple Stain Max-Po (Multi), and 3,3′-diaminobenzidine tetrahydrochloride. Intensity values of 0, 1, 2, and 3 are shown in (A), (B), (C), and (D), respectively. Bar = 50 m. (E) Box-plot analysis of CRKL protein expression in gastric tissue. A statistically significant difference in the CRKL expression level was detected between non-cancerous gastric foveolar epithelium (n = 41) and gastric cancerous tissue (n = 360). (F) Representative result of the CRKL immunohistochemical analysis. A gastric cancer with a high CRKL expression level is shown. Bar = 500 m. The inset is a magnified image. Bar = 50 m. (G) Representative gastric cancer case showing both a high CRKL expression level and CRKL gene amplification. The high CRKL expression level (value = 2.6) was detected using an immunohistochemical analysis. Bar = PubMed ID:http://www.ncbi.nlm.nih.gov/pubmed/27484364 100 m. The inset shows the amplification of CRKL (red) in the cancer cells. The CRKL signal (red) and the control signal for chromosome 22 (green) were detected using.