A complex pattern of mutations and abnormal splicing of Smad4 is present in thyroid tumours.

Sensitivity to transforming growth factor-beta is impaired in thyroid tumours. Similar to Mad -- Mother Against Decapentaplegic-(Smad)4 is frequently altered in cancers, but its involvement in this system is unknown. We analysed 56 thyroid tumours of various histotypes for Smad4 mutations by PCR-SSCP and sequencing, linking them to Smad4 reactivity as examined by immunohistochemistry (IHC), and 29 of them also for abnormalities in RNA expression due to alternative splicing.

Efficient production by sperm-mediated gene transfer of human decay accelerating factor (hDAF) transgenic pigs for xenotransplantation.

A large number of hDAF transgenic pigs to be used for xenotransplantation research were generated by using sperm-mediated gene transfer (SMGT). The efficiency of transgenesis obtained with SMGT was much greater than with any other method. In the experiments reported, up to 80% of pigs had the transgene integrated into the genome.

Transforming growth factor-beta pathway in human renal cell carcinoma and surrounding normal-appearing renal parenchyma.

Objective: To analyze the role of the transforming growth factor (TGF)-beta pathway in renal tumors and to verify whether alterations in TGF-beta 1 pathway expression are associated with the grade of tumor differentiation and pathologic stage in renal cell carcinomas.

Study Design: The expression of TGF-beta 1 and TGF-beta receptors (T beta RI and T beta RII), SMAD-2 and SMAD-4 was investigated by immunohistochemistry in normal peritumoral and tumoral tissue from 53 renal cell carcinomas (clear cell type). The gene expression of SMAD-2 and SMAD-4 was also studied by reverse transcription polymerase chain reaction (RT-PCR) in normal peritumoral and tumoral tissue from 6 of 56 primary tumors.