CASM - AN SM-LIKE PROTEIN THAT CONTRIBUTES TO THE TRANSFORMED STATE IN CANCER CELLS

A novel gene encoding a protein containing Sm motif-like domains was f ound to have elevated expression in pancreatic cancer and in several c ancer-derived cell lines, CaSm (for Cancer-associated Sm-like) mRNA is up-regulated in 87.5% (seven of eight) of pancreatic tumor/normal pai rs, Similarly, cell lines from cancers originating in liver, ovary, lu ng, and kidney show increased CaSm expression compared to their normal tissue cognates, CaSm encodes a 133-amino acid open reading frame tha t contains the two Sm moths found in the common snRNP proteins, with t he greatest homology to the Sm G protein (60% similarity), Two hypothe tical proteins from Caenorhabditis elegans and Saccharomyces cerevisia e share even greater similarity (72.8 and 67.7%, respectively), sugges ting a broad family of proteins containing Sm moths, Antisense CaSm RN A is able to alter the transformed phenotype of pancreatic cancer cell s by reducing their ability to form large colonies in soft agar when c ompared to untransfected cells, Therefore, CaSm expression appears to be necessary for maintenance of the transformed state.