Gastrointestinal tract tumors and cell lines possess differential splicing factor expression and tumor associated mRNA isoform formation profiles.

BACKGROUND: Cell lines derived from human tumors have been extensively used as experimental models of neoplastic disease. Although such cell lines differ from both normal and cancerous tissue. OBJECTIVE: The data obtained used DNA and RNA microarray systems does not give full information about protein expression levels in cells and tissues. We present experimental evidence that splicing factor SRSF1, SRSF2, U2AF35, U2AF65 and KHSRP expression levels in gastrointestinal tract (colon, gastric and pancreatic) tumors differ compare to healthy tissues and in cell lines, derived from corresponding organs. METHODS: Protein expression was analyzed using Western blots. RT-PCR method was used for Fas and Rac splicing analysis. RESULTS: Obtained results provided a novel molecular characterization of this important group of human cell lines and their relationships to tumors in vivo. Expression levels of individual splicing factors in tumors might serve as tumor markers. Not all experimental results obtained from cell lines reflect changes that occur in tumors. Also Fas and Rac, cancer associated genes, tumor associated sFas and Rac1b mRNA isoform profiles in cell lines do not correspond to profiles that are observed in tumors. CONCLUSIONS: Not all experimental results obtained in cell lines reflect changes that occur in real tumors.