Drug repurposing is transforming the health care world. The idea that old, previously-- FDA approved drugs could be altered and to be used again for the treatment of other diseases has been for quiet sometime fairly successful.
Now, recent pre-clinical research at the University of Alabama-Birmingham (UAB), concluded that cancer inhibiting drugs vorinostat, belinostat and panobinostat may be useful for repurposing in the treatment of infections caused by human papillomaviruses, or HPVs.
According to the World Heath Organization, HPV infections in 2012 have resulted in 266,000 deaths from cervical cancer worldwide. Although in developed countries routine screening by Pap smears or through HPV DNA testing reduced the incidence of death in comparison to less developed regions—still an estimated 12,200 women in the US are plagued with cervical cancer each year.
Effective vaccines against HPV exist -- including the recently approved Gardasil 9 that protects against nine confirmed genotypes of HPV. However, such vaccine is only there therapeutically effective if administered before an individual is sexually active. "Safe, effective and inexpensive therapeutic agents are urgently needed," says lead author and assistant professor of Biochemistry and Molecular Genetics at UAB, N. Sanjib Banerjee, Ph.D.
Learn more about how the HPV vaccine works:
The UAB study discovered that the productive program of HPV is highly dependent on the differentiation of the infected site of the epithelium into a squamous epithelium. Therefore, the researchers used an HPV-18 model raft cultures and found that the vorinostat cancer drug inhibited HPV-18 DNA amplification and virus production. Additionally, it was found to result in the programmed cell death called apoptosis in some cells that were fully differentiated.
The researchers went on to use the two remaining cancer inhibiting drugs--belinostat and panobinostat--on the infected differentiated raft cultures. Similar to vorinostat, the drugs were observed to have the same effects.
"On the basis of these detailed studies, we suggest that HDAC inhibitors [vorinostat, belinostat and panobinostat] are promising compounds for treating benign HPV infections, abrogating progeny production and hence interrupting infectious transmission,” says Banerjee. "But further investigation would be required to verify that these agents could also be useful in treating HPV associated dysplasias and cancers.”