pRB2/p130 target genes in non-small lung cancer cells identified by microarray analysis

Abstract

The retinoblastoma gene family consisting of RB/p105, p107, and RB2/p130 cooperate to regulate cell-cycle progression through the G1 phase of the cell cycle. Previous data demonstrated an independent role for the reduction or loss of pRb2/p130 expression in the formation and/or progression of lung carcinoma. Rb2/ p130 is mutated in a human cell line of lung small cell carcinoma as well as in primary lung tumors. To identify potential pRb2/p130 target genes in an unbiased manner, we have utilized an adenovirus-mediated expression system of pRb2/p130 in a non-small lung cancer cell line to identify specific genes that are regulated by pRb2/p130. Using oligonucleotide arrays, a number of Rb2/p130 downregulated genes were identified and their regulation was confirmed by semiquantitative reverse transcriptionpolymerase chain reaction (RT-PCR) and Western blot analysis. As a result, 40 genes showed greater than 2.0-fold modification in their expression level after the RB2/ p130 viral transduction. In conclusion, coupling adenoviral overexpression with microarray and semiquantitative RT-PCR analyses proved to be a versatile strategy for identifying pRb2/p130 target genes and for better understanding the expression profiles of these genes. Our results may also contribute to identifying novel therapeutic biomarkers in lung carcinoma.

pRb2/p130, Vascular Endothelial Growth Factor, p27(KIP1), and Proliferating Cell Nuclear Antigen Expression in Hepatocellular Carcinoma

“…It is possible that in our study group, hepatocarcinoma is independent from p27 (KIP1) expression levels, suggesting another possible molecular scenario in which other protein products could be involved, leaving the following question open: are there any other biomarkers involved in HCC etiology? Recently, in our laboratory we were able for the first time to identify new target genes, the expression of which is modulated by pRb2/ p130 (48). Moreover, we have demonstrated previously that RB2/p130 inhibits angiogenesis in vitro and in vivo by downregulating VEGF expression at the transcriptional and translational levels (40).…”

Regulation of lung endoderm progenitor cell behavior by miR302/367

“…4I). Rbl2 and Cdkn1a were further selected for analysis because of their importance in the regulation of the cell cycle, as well as in malignant tumor progression (Tanaka et al, 2001;Russo et al, 2003;WikenheiserBrokamp, 2004;Simpson et al, 2009). Western blots and immunohistochemistry demonstrated significant reduction in protein expression of Rbl2 and Cdkn1a in Sftpc:miR302/367 transgenic lungs (Fig.…”

Role of cell‐cycle regulators in lung cancer

“…Recently, we have demonstrated that Rb2/p130 gene exhibits oncosuppressor properties in vitro and in vivo in lung adenocarcinoma and modulates angiogenesis by inhibiting vascular endothelial growth factor expression (Claudio et al, 2001). Moreover, we were able to identify Rb2/ p130 point mutations in primary lung cancer (Claudio et al, 2000) and to study the expression of pRb2/p130 target genes in a lung cancer cell line by microarray analysis (Russo et al, 2003). Today, several lung cancer microarray studies are available (Bhattacharjee et al, 2001;Garber et al, 2001;Goodwin et al, 2001;Nacht et al, 2001;Bangur et al, 2002;Beer et al, 2002;Chen et al, 2002Chen et al, , 2003Gordon et al, 2002;Heighway et al, 2002;Miura et al, 2002;Wigle et al, 2002;Kikuchi et al, 2003;Powell et al, 2003).…”