In the July issue of the journal Molecular Cancer Therapy, National Institute of Dental and Craniofacial Research (NIDCR) grantees and colleagues report early results of such a synergism in the treatment of head and neck squamous cell carcinoma. The work builds on the earlier discovery that a novel proteasome-inhibitor called PS-341 induces programmed cell death, or apoptosis, in laboratory studies with cultured tumor cells. The data of several research groups have shown that the drug’s potent effect seems to stall in clinical studies with certain tumor types, suggesting other cell signaling pathways kick into action, override the apoptotic signal, and allow tumor cells to survive. This unexpected outcome led to further brainstorming and ultimately reports that the simultaneous administration of PS-341 (also called bortezomib) and another type of chemotherapeutic agent called a histone deacetylase inhibitor might restore the apoptotic signal. In the current study, the NIDCR researchers show this to be the case for head and neck squamous cell carcinoma and pinpoint the biochemical action that allows the apoptosis to proceed. They conclude the synergistic combination of PS-341 and a histone deacetylase inhibitor, in this case trichostatin A, represents a potential novel therapeutic strategy for treating this common form of head and neck cancer.
(Source: NIDCR, Science News in Brief, July 19, 2010)