Recent studies suggest that acetylation of the p53 tumor suppressor protein is not important for its DNA binding activity, as was previously thought. We discuss here a number of theories as to how this modification may serve to regulate the protein's functions.

Nikolaev et al. (this issue of Cell) report the identification of a parkin-like protein, Parc, and its role in anchoring the tumor suppressor protein p53 in the cytoplasm reveals yet another level of control of p53 function. Regulation of the subcellular localization of p53 by Parc may serve as a novel target in treatment of certain types of tumors.

The tumor suppressor LKB1 has emerged as a critical regulator of cell polarity and energy‐metabolism. Studies in diverse model organisms continue to unravel the pathways downstream of LKB1; the emerging picture is that the outcomes of LKB1 signaling are mediated by a plethora of tissue‐specific and context‐dependent effectors.

The p53 protein is finally swimming into focus. This became clear at the Sixth International p53 meeting, which was held in Israel in Tiberias on the shores of the Sea of Galilee in early November 1992. In recent years, the p53 protein has captured the imagination of a broad spectrum of biomedical researchers. Because of its potentially central role in human cancer, there is considerable impetu...

Computational protein chemistry has potential to contribute to the development of new therapeutic approaches in medicine in several different ways, including indirectly by increasing understanding of the disease-associated changes in protein structure that are mechanistically important, which can have diagnostic implications, as well as directly in designing peptides to counteract the patho-phy...

Liver cancer is one of the most lethal cancers. Quiescent liver expresses up to 20 tumor suppressor proteins including Rb, p53, CCAAT-Enhancer-Binding Protein (C/EBP)α, Hepatocyte Nuclear Factor (HNF4)α and p16 and it is well protected from development of liver cancer. However, the negative control of liver proliferation by these factors and other tumor suppressor genes is eliminated in liver c...

The Runt related transcription factors (RUNX) are recognized as key players in suppressing or promoting tumor growth. RUNX3, a member of this family, is known as a tumor suppressor in many types of cancers, although such a paradigm was challenged by some researchers. The TGF-β pathway governs major upstream signals to activate RUNX3. RUNX3 protein consists of several regions and domains. The Ru...

The Runt related transcription factors (RUNX) are recognized as key players in suppressing or promoting tumor growth. RUNX3, a member of this family, is known as a tumor suppressor in many types of cancers, although such a paradigm was challenged by some researchers. The TGF-β pathway governs major upstream signals to activate RUNX3. RUNX3 protein consists of several regions and domains. The Ru...

The ovine betaretroviruses jaagsiekte sheep retrovirus (JSRV) and enzootic nasal tumor virus (ENTV) cause contagious cancers in the lungs and upper airways of sheep and goats. Oncogenic transformation assays using mouse and rat fibroblasts have localized the transforming activity to the Env proteins encoded by these viruses, which require the putative lung and breast cancer tumor suppressor hya...

Deleted in liver cancer (DLC1) is a candidate tumor suppressor gene recently isolated from human hepatocellular carcinoma. Structurally, DLC1 protein contains a conserved GTPase-activating protein for Rho family protein (RhoGAP) domain, which has been thought to regulate the activity of Rho family proteins. Previous studies indicated that DLC1 was frequently inactivated in cancer cells. In the ...