Their findings are reported in two studies: "Tumor-specific exon 1 mutations could be the 'hit event' predisposing Rb2/p130 gene to epigenetic silencing in lung cancer" and "Genetic and epigenetic alterations of RB2/p130 tumor suppressor gene in human sporadic retinoblastoma: implications for pathogenesis and therapeutic approach," both of which appear in September issues of Oncogene (http://www.nature.com/onc).
The joint studies at Temple and Siena were coordinated by Antonio Giordano, M.D., Ph.D., director of Sbarro Institute at Temple (http://www.shro.org), and by Marcella Macaluso of the Sbarro Institute and Caterina Cinti of both Centro Nazionale Ricerche and the University of Siena.
Giordano said that the researchers were puzzled when they found Rb2/130, the tumor suppressing gene discovered by Giordano in the early 1990s, in an epigenetic state in both the NSLC and retinoblastoma cells. In this epigenetic state, the gene showed no signs of mutation, but is silent in its expression or function.
Further examination of the gene found that it had been methylated, a process in which methyl or chemical groups attached themselves to the gene, attacking a sequence of the Rb2/p130's DNA and thus causing it to cease functioning.
"These studies are providing very important information on how cancerous and pre-cancerous conditions can be detected by the presence of the methylated state of Rb2/p130," said Giordano. "These cancerous or pre-cancerous conditions can be treated with drugs or agents that de-methylate the R
Contact: Preston M. Moretz