Fluorescent in situ hybridization with centromer and PRL-3 probe on MM cell lines and CRO-AP5. The results of FISH analysis with PRL-3 probe (SpectrumOrange) and centromer probe (SpectrumAqua). The red signals mark PRL-3 (8q24.3) and the aqua marks the centromer on chromosome 8. The cell nucleus is stained with DAPI. Original magnification is ×1000. (A) The OH-2 cell line has a normal chromosome 8 with 2 centromer signals and 2 PRL-3 signals. (B) The RPMI-8226 cell line has 2 centromer signals and 3 PRL-3 signals. (C) The CRO-AP5 cell line has 2 centromer signals and 4 to 5 PRL-3 signals, indicating that the area where the PRL-3 gene is located is amplified. (D) The IH-1 cell line has 5 PRL-3 signals and 5 centromer signals, demonstrating polyploidy of chromosome 8.