Overexpression of PLD2 in papillary thyroid tumor tissue. (A) Normal and cancer tissue extracts from 6 patients who underwent surgery for malignant papillary thyroid cancer were prepared as described in Methods. The tissue extracts and transfectant controls of PLD1/PLD2 were applied to SDS-PAGE for Western blotting with antibodies directed against PLD and β-actin. (B) Immunohistochemistry of PLD in normal and cancerous tissue. PLD2 was highly expressed in papillary thyroid cancer tissue (B) compared to faintly stained normal thyroid tissue (A). (C, D) Negative isotype control with preimmune mouse IgG1. Original magnification, 100×. (C) Expression of RET/PTC-1 in malignant papillary thyroid cancer tissue. After the normal and cancer tissues were lysed and the total RNA was isolated, RT-PCR was performed with the primers specific to the human RET/PTC1 and GAPDH. After the PCR amplification, the products were separated by agarose gel electrophoresis and visualized using ethidium bromide staining. The results are representative of three independent experiments.