About
our guest MASSIMO PALMARINI on March 19th 2002 About
our guest MASSIMO PALMARINI on March 19th 2002
Massimo Palmarini obtained a D.V.M. in Perugia (I) and a Ph.D. in Edinburgh (UK) in 1997. Since 2001 he is assistant professor at the Department of Medical Microbiology and Parasitology at the College of Veterinary Medicine University of Georgia in Athens (USA).
He focuses on the study of the pathogenesis and oncogenesis of ovine pulmonary carcinoma (OPC). OPC is a naturally occurring contagious lung cancer of sheep associated with a betaretrovirus known as jaagsiekte sheep retrovirus (JSRV). OPC has striking similarities with human bronchioalveolar carcinoma (BAC). In both tumors the differentiated epithelial cells of the lungs, type II pneumocytes and Clara cells, are the transformed cells that give rise to the neoplasm (Palmarini, M. et al 1997. Trends Microbiol. 5:478.). Recently, the first JSRV infectious molecular clone (JSRV21) have been isolated and the classical signs of OPC could be reproduced experimentally by inoculating new-born lambs with such a molecular clone (Palmarini, M. et al, 1999, Journal of Virology 73: 6964). Thus, JSRV is the etiological agent of OPC.
Retroviruses have been an invaluable tool to dissect the multistep events leading to cancer. The common mechanisms involved in retrovirus-induced neoplasms extend to tumors that lack retroviral etiology. For example many of the genes that have been first identified as retroviral transduced oncogenes (e.g. ras, myc, abl, erbB ) are now known to be activated in certain type of human cancers. OPC is a unique model of retrovirus-induced lung cancer and understanding the mechanisms involved in OPC carcinogenesis can offer new insights into lung tumorigenesis. Recently it was shown that the envelope of JSRV is able to transform NIH-3T3 cells in vitro. Thus JSRV might induce cell transformation by stimulating directly a cell-surface protein (Maeda, N. et al 2001. Proc Natl Acad Sci U S A. In press). In addition, by microarray analysis a set of genes that are differentially expressed in JSRV-transformed 3T3 have identified by Massimo Palmarini´s group. Thus, the main aim of this laboratory is to understand the molecular mechanisms of cell transformation by JSRV and to test wheter the results obtained by the in vitro transformation assays are a fair representation of the carcinogenic events in vivo.
Links:
a few impressions of Prof. Palmarini´s talk on March 19th 2002 which was titled
"Pathogenesis
and mechanisms of cell transformation in a retrovirus-induced lung cancer
of
sheep, a unique animal model for human pulmonary adenocarcinomas"
PS:
After a couple of hosted events we still don´t really know how to work
the digital camera, that is
our pictures keep staying away from getting sharp! ;O) ´Will try to
get better in that the next time.
PPS:
Special thanks to the VUW for financial support and infrastructure as always!
sources: Univ. of Georgia, NCBI, et al.; (AB/II-02)