TY - JOUR T1 - Preferential Expression of the Secreted and Membrane Forms of Tumor Endothelial Marker 7 Transcripts in Osteosarcoma JF - Anticancer Research JO - Anticancer Res SP - 4317 LP - 4322 VL - 29 IS - 11 AU - CHANDRALEKHA HALDER AU - CHRISTIAN OSSENDORF AU - AVUDAIAPPAN MARAN AU - MICHAEL YASZEMSKI AU - MARK E. BOLANDER AU - BRUNO FUCHS AU - GOBINDA SARKAR Y1 - 2009/11/01 UR - http://ar.iiarjournals.org/content/29/11/4317.abstract N2 - Background: High expression of tumor endothelial marker 7 (TEM7) is correlated with osteogenic sarcoma (OS) metastasis and poor survival of patients. The TEM7 gene produces four alternatively spliced transcripts with distinct functional domains; the expression pattern of these transcripts in OS is unknown. Materials and Methods: mRNA expression was assessed in 5 OS cell lines, 7 normal bone, and 9 OS tumor specimens by reverse transcriptase polymerase chain reaction. Results: All OS cell lines, 6/9 tumors but none of the bone specimens expressed mRNA of TEM7 secreted forms 1 and 2. A total of 3/5 OS cell lines, 8/9 of tumors and 4/7 of bone specimens expressed mRNA of the TEM7 intracellular form. One out of 5 cell lines, 2/7 tumors and none of the bone specimens expressed mRNA of the TEM7 membrane form. The secreted forms had 20-fold higher expression in metastatic (LM7) compared to non-metastatic (SAOS-2) cells. Conclusion: The mRNA of secreted and the membrane forms of TEM7 are preferentially expressed in OS. ER -