MeduIIary thyroid carcinoma (MTC) occurs both sporadically and in the autosomal dominantly inherited multiple endocrine neoplasia (MEN) type 2 syndromes. The distinction between true sporadic MTC and a new mutation familial case is important for future clinical management of both the patient and family. The susceptibility gene for hereditary MTC is the RET proto-oncogene. DNA analysis for g...

Products of ras genes are putative elements of growth factor signal transduction. However, the mechanism of action of these proteins in normal and malignant growth is as yet obscure. To test for functional consequences of ras oncogene expression, electrophysiological experiments were performed on NIH-3T3 fibroblasts transfected with a transforming Ha-ras MMTV-LTR construct expressing the oncoge...

The small heat-shock protein of 27 kDa (HSP27) is highly expressed in many cancers and is associated with aggressive tumour behaviour, metastasis, poor prognosis and resistance to chemotherapy. We aimed at assessing the role of HSP27 in modulating responses to target therapies. We selected several oncogene-addicted cancer cell lines, which undergo either cell cycle blockade or cell death in res...

Oncogene-induced senescence acts as a barrier against tumour formation and has been implicated as the mechanism preventing the transformation of benign melanocytic lesions that frequently harbour oncogenic B-RAF or N-RAS mutations. In the present study we systematically assessed the relative importance of the tumour suppressor proteins p53, p21(Waf1), pRb and p16(INK4a) in mediating oncogene-in...

Vav family members function as remarkable scaffold proteins that exhibit both GDP/GTP exchange activity for Rho/Rac GTPases and numerous protein-protein interactions via three adaptor Src-homology domains. The exchange activity is under the unique regulation by phosphorylation of tyrosine residues hidden by intra-molecular interactions. Deletion of the autoinhibitory N-terminal region results i...

The BCR/ABL oncogene encodes an activated tyrosine kinase that causes human chronic myelogenous leukemia. The mechanism of transformation, however, is complex and not well understood. One of the important contributions of BCR to transformation is believed to be dimerization or oligomerization of ABL, thereby activating ABL tyrosine kinase activity. We reasoned that if ABL was dimerized through ...

During Drosophila development, cells with elevated levels of the Myc oncoprotein grow faster than, and induce cell death in, nearby wild-type cells, suggesting how inappropriate Myc over-expression provides cells with a competitive advantage that can lead to cancer.

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