Rather funky finding reported today in the Journal for Clinical
Investigation.  Yet another plant-derived pharmaceutical it seems...and
of course confirmatory proof (as if we needed it) that HHV8 causes KS.

Fulltext online at http://www.jci.org/cgi/reprint/115/3/642.pdf (may
need institutional access - I don't know)

Abstract at http://www.jci.org/cgi/content/abstract/115/3/642

Cheers

Bennett

******

Glycyrrhizic acid alters Kaposi sarcoma-associated herpesvirus
latency, triggering p53-mediated apoptosis in transformed B lymphocytes

Francesca Curreli1, Alvin E. Friedman-Kien1,2 and Ornella Flore1,2

Kaposi sarcoma-associated herpesvirus (KSHV) is linked with all
clinical forms of Kaposi sarcoma and several lymphoproliferative
disorders. Like other herpesviruses, KSHV becomes latent in the
infected cells, expressing only a few genes that are essential for the
establishment and maintenance of its latency and for the survival of
the infected cells. Inhibiting the expression of these latent genes
should lead to eradication of herpesvirus infection. All currently
available drugs are ineffective against latent infection. Here we show,
for the first time to our knowledge, that latent infection with KSHV in
B lymphocytes can be terminated by glycyrrhizic acid (GA), a
triterpenoid compound earlier shown to inhibit the lytic replication of
other herpesviruses. We demonstrate that GA disrupts latent KSHV
infection by downregulating the expression of latency-associated
nuclear antigen (LANA) and upregulating the expression of viral cyclin
and selectively induces cell death of KSHV-infected cells. We show that
reduced levels of LANA lead to p53 reactivation, an increase in ROS,
and mitochondrial dysfunction, which result in G1 cell cycle arrest,
DNA fragmentation, and oxidative stress-mediated apoptosis. Latent
genes are involved in KSHV-induced oncogenesis, and strategies to
interfere with their expression might prove useful for eradicating
latent KSHV infection and have future therapeutic implications.