[Rac subfamily expression and activity in gastrointestinal cancer cell lines].

Objective: To investigate the significance of Rac subfamily members in the gastrointestinal carcinogenesis and progression.

Methods: The mRNA expression of Rac1, Rac2 and Rac3 in 12 kinds of gastrointestinal cancer cell lines was examined by semi-quantitative RT-PCR. The activities of Rac1 protein in 5 kinds of gastric cancer cell lines were tested by pull-down assay.

Small interfering RNA: a new tool for gene therapy.

The use of anti-gene agents to disrupt the expression of disease-related genes could potentially be of utility in the treatment of a large number of illnesses, including most neoplasms. Traditional anti-gene agents include antisense oligonucleotides and ribozymes. Recent observations have provided evidence for another promising anti-gene technology-RNA interference (RNAi), in which the introduced double-stranded RNA (dsRNA), after a complicated series of processing steps, disrupts the expression of the targeted cellular gene.

Activation of clg, a novel dbl family guanine nucleotide exchange factor gene, by proviral insertion at evi24, a common integration site in B cell and myeloid leukemias.

Retroviruses induce leukemia in inbred strains of mice by activating cellular proto-oncogenes and/or inactivating tumor suppressors. The proviral integration sites in these leukemias provide powerful genetic tags for disease gene identification. Here we show that Evi24, a common site of retroviral integration in AKXD B cell and BXH-2 myeloid leukemias, contains a novel Dbl family guanine nucleotide exchange factor gene.