Transporters tumor suppressor

New examples of cellular rhythms have recently been uncovered (Table II). These include periodic changes in the intracellular concentration of the transcription factor NF-KB and of the tumor suppressors p53, stress-induced oscillations in the transport of the transcription factor Msn2 between cytoplasm and nucleus in yeast, the segmentation clock that is responsible for the... 

Hochstrasser M (1998) There s the rub a novel ubiquitin-like modification linked to cell cycle regulation. Genes Dev 12 901-907 Hochstrasser M, Johnson PR, Arendt CS, Amerik AY, Swaminathan S, Swanson R, Li SJ, Laney J, P s Ryiaarsdam R, Now J, Connerly PL (1999) The Saccharomyces cerevisiae ubiquitin-proteasome system. Philosophical Transactions of the Royal Society of London Series B Biological Sciences 354 1513-1522 Honda R, Tanaka, H Yasuda H (1997) Oncoprotein MDM2 is a ubiquitin ligase E3 for tumor suppressor p53. FEBS Lett 420 25-27 Hood JK, Silver PA (1999) In or out Regulating nuclear transport. Curr Opin Ceil Biol 11 241-247... 

Besides the role of drug carriers in cancer, some membrane transporters have been demonstrated to act as tumor suppressor genes and be silenced by DNA methylation in colon cancer, and some transporters have been shown to be involved in EMT. As a consequence, membrane transporters may be differentially expressed between... 

Lutterbaugh, J., Rerko, R.M., Casey, G., Issa, J.P. et al. (2003) SLC5A8, a sodium transporter, is a tumor suppressor gene silenced by methylation in human colon aberrant crypt foci and cancers. Proceedings of the National Academy of Sciences of the United States of America, 100 (14), 8412-8417. 

Etoposide and teniposide are similar in their actions and in the spectrum of human tumors affected. Unlike podophyllotoxin, but like the anthracyclines, they form a ternary complex with topoisomerase 11 and DNA and prevent resealing of the break that normally follows topoisomerase binding to DNA. The enzyme remains bound to the free end of the broken DNA strand, leading to an accumulation of DNA breaks and cell death. Cells in the S and G2 phases of the cell cycle are most sensitive to etoposide and teniposide. Resistant cells demonstrate ampMcation of the mdr-1 gene that encodes the P-glycoprotein drug efflux transporter, mutation or decreased expression of topoisomerase 11, or mutations of the p53 tumor suppressor gene, a required component of the apoptotic pathway. 

J. Chen, and J. Russo, Dysregulation of glucose transport, glycolysis, TCA cycle and glutaminolysis by oncogenes and tumor suppressors in eaneer cells. Biochim. Biophys. Acta., 1826 (2012)370-84. 

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