The RASSF8 gene, which maps close to the KRAS2 gene, contains a RAS-associated 
domain and encodes a protein that is evolutionarily conserved from fish to 
humans. Analysis of the RASSF8 transcript revealed a complex expression pattern 
of 5'-UTR mRNA isoforms in normal lung and in lung adenocarcinomas (ADCAs), with 
no apparent differences. However, RASSF8 gene transcript levels were 
approximately seven-fold-lower in lung ADCAs as compared to normal lung tissue. 
Expression of RASSF8 protein by transfected lung cancer cells led to inhibition 
of anchorage-independent growth in soft agar in A549 cells and reduction of 
clonogenic activity in NCI-H520 cells. These results raise the possibility 
protein encoded by RASSF8 is a novel tumor suppressor for lung cancer.